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https://www.math.rutgers.edu/academics/graduate-program/1279-syllabus-of-the-spp-algebra-program	## Syllabus of the SPP Algebra Program To provide an in-depth review and to fill in gaps in some background material in Abstract Linear Algebra, which is often presumed in standard first year graduate courses. The material to be covered is also part of the syllabus of the qualifying exams on Algebra. Below is a tentative list of topics to be covered; the actural coverage may vary depending on the instructor. • Vector spaces, isomorphism, linear transformations: basis, dimension, quotient spaces, direct sums, rank and nullity. Coordinatization. • Examples from various places: geometry, linear ODE, quantum mechanics, graph theory, etc. • Similarity, eigenvalues, diagonalization, Jordan canonical form, application to ODE's and other areas, Rational canonical form. • Role of the ground field (or extended ground field): In particular applications involving linear operators on vector spaces over the complex field (E.g. Jordan canonical form) • Bilinear forms, sesquilinear forms, nondegeneracy, Euclidean and Unitary inner products. • Some detailed study of Hermitian and unitary matrices, in particular, diagonalization involving Hermitian and unitary matrices. Basic properties of orthogonal and unitary groups. Self-adjoint linear transformations. • Duality, esp. finite-dimensional case. • Additional topics, if time permits: tensor product defined by naming basis, symmetric and wedge square, higher powers, determinants, Kronecker product, $$V^*\otimes W$$, differential forms, Schur duality. ## Contacts Departmental Chair Michael Saks	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9057779908180237, "perplexity": 3274.650864387563}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-13/segments/1521257651780.99/warc/CC-MAIN-20180325025050-20180325045050-00005.warc.gz"}
http://math.shinshu-u.ac.jp/~bxie/	## 謝　賓　(シャ　ビン) English 〒390-8621 長野県松本市旭3-1-1 メール: bxie AT shinshu-u.ac.jp ## 著書 • 舟木直久，乙部厳己，謝賓，確率偏微分方程式 (岩波数学叢書)，単行本，岩波書店，2019年3月，335ページ．ISBN: 9784000298254. ## 論文リスト • 査読付き • L. Goudenège, B. Xie, Ergodicity of stochastic Cahn-Hilliard equations with logarithmic potentials driven by degenerate or nondegenerate noises. J. Differential Equations 269 (2020), no. 9, 6988–-7014. doi.org/10.1016/j.jde.2020.04.047. • B. Xie, A note on random strings with values in a bounded convex domain, RIMS Kôkyûroku Bessatsu, B79 (2020), Res. Inst. Math. Sci. (RIMS), 199--213. • M. Niu and B. Xie, Comparison theorem and decorrelation for stochastic heat equation driven by Lévy space-time white noise, Discrete & Continuous Dynamical Systems - B, 24 (2019), no. 7, 2989--3009. doi: 10.3934/dcdsb.2018296. • B. Xie, Hypercontractivity for space–time white noise driven SPDEs with reflection. J. Differential Equations 266 (2019), no. 9, 5254--5277. doi:10.1016/j.jde.2018.10.022. • M. Niu and B. Xie, Wang's Harnack inequalities for space-time white noises driven SPDEs with two reflecting walls and their applications. J. Math. Anal. Appl. 469 (2019), no. 2, 568--593. • B. Xie, Intermittency for stochastic partial differential equations driven by strongly inhomogeneous space-time white noises. J. Differential Equations 264 (2018), no. 2, 1050–-1079. • B. Xie, Some effects of the noise intensity upon non-linear stochastic heat equations on $[0,1]$, Stochastic Process. Appl., 126 (2016), 1184--1205. • T. Funaki, M. Sasada, M. Sauer and B. Xie, Fluctuations in an evolutional model of two-dimensional Young diagrams, Stochastic Process. Appl., 123 (2013), 1229--1275. • J.-L. Wu and B. Xie, On a Burgers type nonlinear equation perturbed by a pure jump Lévy noise in $R^d$, Bull. Sci. Math., 136 (2012), 484--506. • B. Xie, Impulsive noise driven 1-dimensional higher order fractional partial differential equations, Stochastic Analysis and Applications, 30 (2012), 122--145. • M. Niu and B. Xie, Impacts of Gaussian noises on the blow-up times of nonlinear stochastic partial differential equations, Nonlinear Analysis: Real World Applications, 13 (2012), 1346--1352. • B. Xie, Uniqueness of Invariant Measures of Infinite Dimensional Stochastic Differential Equations Driven by Lévy Noises, Potential Analysis, 36 (2012), 35--66. • B. Xie, The growth estimates for direction dependent random fields, Far East J. Math. Sci. (FJMS), 44 (2010), 181--195. • M. Niu and B. Xie, Regularity of a fractional partial differential equation driven by space-time white noise, Proc. Amer. Math. Soc., 138 (2010), 1479--1489. • T. Funaki and B. Xie, A stochastic heat equation with the distributions of Lévy processes as its invariant measures, Stochastic Process. Appl., 119 (2009), 307--326. • B. Xie, On pathwise uniqueness of stochastic evolution equations in Hilbert spaces. J. Math. Anal. Appl. 344 (2008), no. 1, 204-–216. • B. Xie, The moment and almost surely exponential stability of stochastic heat equations. Proc. Amer. Math. Soc. 136 (2008), no. 10, 3627–-3634. • B. Xie, Stochastic differential equations with non-Lipschitz coefficients in Hilbert spaces, Stoch. Anal. Appl., 26 (2008), 408--433. • B. Xie, The stochastic parabolic partial differential equation with non-Lipschitz coefficients on the unbounded domain, J. Math. Anal. Appl., 339 (2008), 705--718. • L. Lei, L.-M. Wu and B. Xie, Large Deviations and Deviation Inequality for Kernel Density Estimator in $L^1 (R^d)$-distance, Development of Modern Statistics and Related Topics, Ser. Biostat., 1 (2003), 89--97, World Sci. Publishing. • B. Xie, Hypercontractivity of Hamilton-Jacobi equations and related inequalities, J. Math. (Wuhan), 23 (2003), 397--402. • その他の論文 • 謝賓, Harnack inequalities for the stochastic partial differential equations with reflecting walls and their applications, 統計数理研究所共同研究リポート402，無限分解可能過程に関連する諸問題, 22 (2018), 104--111. • 謝賓, Intermittency and noise excitation for stochastic heat equations driven by various noise, 統計数理研究所共同研究リポート385，無限分解可能過程に関連する諸問題, 21 (2017), 48--53． • B. Xie, SPDEs deduced from evolutional models of two-dimensional Young diagrams, RIMS Kôkyûroku, 1905 (2014), 18--29. • 謝賓, 舟木直久, A stochastic heat equation with the distributions of Lévy processes as its invariant measures, 統計数理研究所共同研究リポート225，無限分解可能過程に関連する諸問題, 13 (2009), 16--21．	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5425072312355042, "perplexity": 2415.266955108824}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-45/segments/1603107887810.47/warc/CC-MAIN-20201025041701-20201025071701-00289.warc.gz"}
https://ask.sagemath.org/question/46958/updating-sage-in-windows-10/	# Updating Sage in Windows 10 edit The Sage Installation Guide Release 8.7 seems to assume that one installs Sage in Windows using Cygwin, in particular regarding upgrading. However, I installed Sage on Windows 10 from the bin files without installing Cygwin at all. How should I update both Sage and the packages? I favour an easy way that does not make me uninstall-reinstall. edit retag close merge delete 1 What do you mean "from the bin file"? If you downloaded the installer from https://github.com/sagemath/sage-wind... then you did install SageMath on Cygwin. Concerning update on Windows, I don't think that there is anything easier for now than uninstall-reinstall. ( 2019-06-23 18:13:28 +0100 )edit @vdelecroix I don't think that is correct. I downloaded bin files here http://www.mirrorservice.org/sites/ww... and then simply ran the installation file. I do not have cygwin installed on my computer. If sagemath installs cygwin and runs over it, it does it in a completely transparent way. I cannot even find a cygwin folder in my computer. ( 2019-06-24 17:15:05 +0100 )edit I still believe that you have installed cygwin! You should check for the presence of c:\program files\cygwin. ( 2019-06-24 21:27:53 +0100 )edit @vdelecroix It is not there. I tell you, I have done a search for cygwin and there is not such directory in the whole disk. ( 2019-06-25 02:37:32 +0100 )edit 3 @vdelecroix's first comment is correct. The SageMath installer for Windows includes its own copy of cygwin built-in, including more-or-less exactly the dependencies it needs to run and nothing more. I'm not sure why you're specifically trying to "find Cygwin", but as @vdelecroix there is unfortunately not yet a specific "upgrade" functionality. You can have multiple versions installed side-by-side, and just uninstall the ones you're not using anymore. ( 2019-07-02 14:43:11 +0100 )edit Sort by » oldest newest most voted I forgot about this question, but just as a quick follow-up Jesus and I met last week at the University of Essex and I walked him through building Sage on Windows/Cygwin using the instructions at: https://trac.sagemath.org/wiki/Cygwin... As we noted at the time, one bit of information currently missing from those instructions is to set: export FFLAS_FFPACK_CONFIGURE=--disable-openmp This is just to work around a slight defect in the build system that should get fixed at some point... more 1 Meant mingw ( 2020-08-01 13:40:39 +0100 )edit Not cygwin, but mintty. C:\Users{username}\AppData\Local\SageMath 8.7 Sagemath does not run natively in Windows. more 1 Hi, I'm not sure what you intended exactly by this answer but it appears to be misleading. Sage on Windows uses Cygwin. MinTTY is just a terminal emulator that is included in Cygwin, and is also the terminal emulator used by default when running Sage for Windows. ( 2020-01-31 18:27:10 +0100 )edit	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.18406856060028076, "perplexity": 4124.248318908531}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2023-06/segments/1674764500288.69/warc/CC-MAIN-20230205193202-20230205223202-00598.warc.gz"}
https://api-project-1022638073839.appspot.com/questions/why-are-organic-compounds-important	Organic Chemistry Topics # Why are organic compounds important? May 10, 2014 Organic compounds have versatile bonding patterns and are part of all organisms. #### Explanation: Organic means that a compound contains carbon. There are some exceptions of this rule like $C {O}_{2}$ carbon dioxide. Organic compounds are important because all living organisms (redundant) contain carbon. The three basic macromolecules of life are Carbohydrates ($C {H}_{2} O$), Fats (lipids) ($C H O$) and Proteins $\left(C H O N\right)$. While these three macromolecules are the basic structures of life, they are the basic components of many of the cycles that drive the earth, primarily the carbon cycle including the exchange of carbon between plants and animals in photosynthesis and cellular respiration. The decomposition of carbon life forms returning to the soil and being regenerated in new plants, eaten by animals and decomposed by detivores. The carbon energy cycle of carbohydrates in organisms but also in fossils fuels becoming petroleum and natural gas. All of the food we eat are reconstituted material and extracts of plants, animals, bacteria and protists. Carbon is so important because of the unique bonding properties that allow carbon molecules to form long chains called polymers or compact well organized rings. These two bonding patterns make carbon one of the most versatile elements for molecular construction. Diamonds, are composed of a carbon compressed under great pressure. Plastics are composed of carbon polymers, even the stealth technology of the B2 Bomber is made of Carbon fibers. This answer only scratches the surface of the value and importance of Carbon. But, I hope it was helpful. SMARTERTEACHER ##### Impact of this question 39595 views around the world	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 4, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.29158657789230347, "perplexity": 4841.381999350143}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-16/segments/1585370519111.47/warc/CC-MAIN-20200404011558-20200404041558-00379.warc.gz"}
https://ctftime.org/writeup/11002	Rating: 5.0 We try /foo and sure enough we see "foo" on the page. Perhaps we can include php on the page? / reminds us that the question mark is for get parameters. Better urlencode it. /%3C%3Fphp%20echo%201%3B%20%3F%3E gives us nothing, but the source shows the attempt was escaped. We got something like back. So they are trying to blacklist commands. Blacklisting has a bad smell about it. After a while of trying to get php to be included, we tried to switch gears and look for other server side includes. /{{session}} worked, we get an object back. After some more fiddling, /{{session.__dict__}} proves this is python and we figure out that this looks like jinja2 templates from flask. We try /{{url_for.__globals__}} which gives us access to some python functionality, the os module (exposed as url_for.__globals__.os) is particularly interesting to us as it allows us to explore the operating system with os.listdir. It should be noted that many things were tried, but os.open and os.popen were blocked to us and things like os.system('scp file location') would error out. Eventually we figure out that we can use flasks send_file which returns a request object, which itself can be displayed through the template with the .text attribute. The final url ended up being: /{{url_for.__globals__.send_file('/opt/app/flag_secret_file_910230912900891283').response.text}} which yields the flag. Original writeup (http://185.168.131.123/).	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.28467243909835815, "perplexity": 2917.7506465535917}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-50/segments/1606141201836.36/warc/CC-MAIN-20201129153900-20201129183900-00118.warc.gz"}
http://link.springer.com/article/10.1007%2Fs10773-008-9764-4	, Volume 47, Issue 12, pp 3288-3297 Date: 03 Jun 2008 # Bulk Viscous Bianchi Type I Cosmological Models with Time-Dependent Cosmological Term Λ Rent the article at a discount Rent now * Final gross prices may vary according to local VAT. ## Abstract Bianchi type I cosmological models with time-varying cosmological constant Λ and bulk viscous fluid are investigated. Cosmic matter is chosen to obey a barotropic equation of state. Exact solutions of Einstein’s field equations are obtained assuming the volume expansion θ proportional to the eigen values of shear tensor σ ij . Physical and kinematical properties of the models are discussed considering bulk viscosity to be a power function of matter density.	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9345292448997498, "perplexity": 1690.545167491027}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-35/segments/1408500835488.52/warc/CC-MAIN-20140820021355-00406-ip-10-180-136-8.ec2.internal.warc.gz"}
https://www.physicsforums.com/threads/re-is-this-normal.176030/	# Re: is this normal? 1. Jul 5, 2007 ### Schrodinger's Dog Someone pm'd me asking for an equation for some problem. However tex tags appear not to work in pm? It just repeatedly says latex is generating an image or some such forever? No matter how many times I refresh? $$F(g)=K(g)\frac{m1\times m2}{r^2}$$ I've cut and pasted this, this is the image. Is that normal, I've never sent tex by pm? Last edited: Jul 5, 2007 2. Jul 5, 2007 ### Staff: Mentor LaTex and attachments aren't supported in PM. 3. Jul 5, 2007 ### Schrodinger's Dog May I ask why? Not that I care honestly, I'm just curious? That's the first time ever anyone's asked me for homework advice in pm I directed him to the homework helper section and gave him the equation I think he needed anyway. Hope it's the right one. 4. Jul 5, 2007 ### Staff: Mentor My guess would be bandwidth. As for attachments, someone could potentially spam a large number of members without us being aware until it was too late. chroot or Greg would know that answer. And anyone that receives an unsolicited request for homework help should refer that person back to the forum, it is, after all, why we exist. 5. Jul 5, 2007 ### chroot Staff Emeritus No, it's not bandwidth. It's that it'd take an awful lot of work for very little gain. Few people have asked for the feature. If more people are interested, I'll consider looking into it. - Warren 6. Jul 5, 2007 ### Schrodinger's Dog Thanks muchly I directed him to the wrong exact section, and the equation wasn't the right one, but I'm sure he'll get an answer presently. Thanks for the advice. 7. Jul 5, 2007 Off topic: welcome back, Schrog !!! 8. Jul 5, 2007 ### Schrodinger's Dog Thanks, you're all so nice today, makes me feel right back at home 9. Jul 6, 2007 ### ranger Indeed, welcome back Schrodinger's Dog. Haven't seen you in a while. 10. Jul 6, 2007 ### Schrodinger's Dog Sup, I've been training up my ninja powers and stuff 11. Jul 6, 2007 ### J77 Yeah -- good to see you back SD 12. Jul 6, 2007 ### Schrodinger's Dog Good to be back	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8368281126022339, "perplexity": 8439.48061592629}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-30/segments/1531676589710.17/warc/CC-MAIN-20180717105812-20180717125812-00385.warc.gz"}
https://blender.stackexchange.com/questions/67346/where-do-the-white-lines-come-from-in-my-composite	# Where do the white lines come from in my composite? I'm having this issue for years now, and I'm not sure if I am doing something wrong on my end, or if what I would like to achieve - or expect to see - is even possible. My question is about compositing artifacts when using Blenders mask layers. Let me explain: In the Blend file provided, there are two objects: Dragon A and B. Each of them is on a separate layer, rendered on a separate render layer, and masked with the other one. So A is masked out by B, and B is masked out by A. Like this: scene setup RenderLayers A and B When I render, I write out two MultiLayer EXRs with 16bit depth. That Stuff, I feed into the following comp: and it gives me this: You can clearly see the white lines around the areas where the dragons mask each other. If I comp in a weird fashion like this: I get this: It's not perfect, but still a lot better than the first one. What I am doing is kind of cutting off the bright alpha values, making a 0.75 alpha value equal 1. My question is: Why do I see the white background shine through after all? Is it something which is fundamentally unchangeable and we have to live with? Am I doing something wrong on my side? Do you have an alternative solution? ## Edit The solution Ray Mairlot came up with solves the issue by only masking one of the two, the other one would exist un-masked underneath, and thus provides a perfect overlay. However, I'd like to still mask one against the other for specific reasons: I'm sending images to a web application, which layers them dynamically (a configurator in essence). There can be 30 or more image layers, each of them needs to be downloaded by the website visitor. If I could mask one part against the other, the individual file size would be smaller. Not really a necessary reason, but that's why the idea came up. The other reason is, if I mask the layers, the individual layers render faster. This can save me some 30% of the render time per configurator (which renders on average for 12 hours). • Did you try checking the "convert premultiply" on the Alpha Over node?? – Samir Rahamtalla Nov 16 '16 at 16:17 • @SamirRahamtalla I did, in this case it makes no difference. I also tried reordering the composition, so first the dragons would be comped, and then I'd comp against white background. No difference. – aliasguru Nov 16 '16 at 16:18 • +1. This is a good question. A very good question. It is Specific and Clear. It shows what you've tried, what you think, and has useful images. I wish this site had more questions like this. – X-27 wants to Reinstate Monica Nov 16 '16 at 16:55 • "Why do I see the white background shine through after all?" The back image can't block the background because it's masked by the front image. The front image is not fully opaque everywhere, so doesn't completely mask the background on its edge. – David Schwartz Nov 16 '16 at 20:22 Those two images you're trying to composite together have "correlated" alphas. The Alpha over operation isn't the appropriate operation for this situation. The solution is simple: you just have to add those images together, then add their alphas together and assign the resulting alpha to the result of the first addition. Here's how: Why alpha-over doesn't work Alpha over is, like its name states, an "over" operation. Something is over something else, covering it. The alpha channel determines the occlusion of the background by the foreground. When you inspect the alpha-over formula for two associated (premultiplied) images, you'll see it's just an addition, but before that addition the alpha channel of the foreground is inverted and multiplied on the background, casting a shadow on the pixels that the foreground occludes. Associated Alpha Over Operation: Foreground.RGB + ( ( 1.0 - Foreground.Alpha ) * Background.RGB ) Porter Duff Alpha Merge Operation Uncorrelated Geometry: Alpha.A + Alpha.B - ( Alpha.A * Alpha.B ) Correlated Geometry: Alpha.A + Alpha.B When alphas are correlated, like in your example, there is no foreground-background situation. It's rather filling a hole in one image with the other image. The hole and the image that will cover it fit perfectly, so there is no reason for casting a shadow on the background. There's already a hole in it. If you use alpha over, the "shadow" of the foreground will be multiplied again on the antialias pixels that are already shadowed by the mask, causing a doubled value of transparency, and that's why you get those semi-transparent pixels where they should be completely opaque. So, skipping the "over" part by just adding the two plates together works perfectly. In Blender you have to add alphas too and assign the result to the mix. • This works like a charm! Would you mind adding a reference to the Alpha Over formula you mention, or insert the formula directly into your answer? This way it might become clearer as of why this solution works, and the other one doesn't. Two years I've spent wondering about this issue, can't believe the solution is that simple... – aliasguru Nov 16 '16 at 20:20 • I would add that thinking about it in terms of probability (remember that alpha in associated alpha imagery is geometry) that we can see A+B - (A*B) turns the latter half into 0 when the geometry "perfectly snaps together". Hence there is no cheating nor hacking here, but rather the same concept considered against the geometry of the original situation, slightly hidden in the fact that the rasterized pixel is blending the geometric result. – troy_s Nov 16 '16 at 20:44 • en.wikipedia.org/wiki/Alpha_compositing Think of alpha channel as a model of emission and occlusion: an object in front of another adds its own light, but also occludes the light coming from the object behind. When you perform an alpha-over operation, it has two parts: it inverts the alpha and multiplies over the background, creating a holdout (that's the occlusion part) Then the foreground is added (that's the emission part). The latter is what we have to use in this case, just the added emission. – Gez Nov 16 '16 at 20:48 • The alpha over formula for each pixel is: Co = Ca + Cb × (1−αa) for colour and αo = αa + αb × (1−αa) for alpha channel. – Gez Nov 17 '16 at 21:04 • Another question related to this. blender.stackexchange.com/questions/75953/… Can this solution be extended to many render layers? – bot4u Sep 27 '17 at 7:15 From what I can see, the error is that your original render layers from your 'Render' scene are set to mask each other out. I can't personally see a reason why you would mask them (particularly not both of them) if you are looking to combine them. Disabling the masking on the renderlayers: And using this node setup: Gets this: • That's a very good advise, +1 for this. In the real world example, I'm sending images to a web application, which layers them dynamically (a configurator in essence). There can be 30 and more image layers, each of them needs to be downloaded by the user. If I could mask one part against the other, the individual file size would be smaller. Not a really necessary reason, but that's why the idea came up. The other reason is, if I mask the layers, the individual layers render faster. This can save me some 30% of the render time per configurator (which renders on average for 12 hours). – aliasguru Nov 16 '16 at 17:05 • But the main reason is: I DON'T GET WHY IT SHOULDN'T WORK :)) – aliasguru Nov 16 '16 at 17:06 • I don't really understand why it would work, but I don't have the knowledge to explain why. I imagine it is to do with each of the objects having partially transparent pixels at their edges leaving a transparent line inbetween them. – Ray Mairlot Nov 16 '16 at 17:26 • Also, I would suggest you add in to the original question that you need each layer to be masked by the other. – Ray Mairlot Nov 16 '16 at 17:35 • I've edited my question as you suggested. Meanwhile, I did some tests in Gimp. I'll try to replicate that tomorrow in Photoshop too, just to make sure, but if I get the same results on that simple test (not the dragons, something different), then you're most likely right: It's impossible. – aliasguru Nov 16 '16 at 18:52 You don't need two Aplha Over nodes. This way it works: • Thanks for the answer, but the problem is: I need to see my comp against white, as the final output will be on a white backplate (studio shot). The white background was not added by accident. – aliasguru Nov 16 '16 at 15:25 • I think the problem is in the render, because if I open them in Photoshop and layer them on top of each other there is the same issue. – float Nov 16 '16 at 15:35 • I see the same issue, also when we comp in AfterEffects or Nuke. But why is it behaving like that? It might be that this effect we see is totally valid and makes sense (from a math point of view), but I haven't been able to figure out why. – aliasguru Nov 16 '16 at 17:08 The problem is that you're overlaying the silver dragon with a white background, before you overlay it on the orange dragon. Just use one alpha-over. One image with an alpha channel goes into one slot and gets overlayed onto another image which goes into the other slot, instead of the white color. • Thanks for the answer, but the problem is: I need to see my comp against white, as the final output will be on a white backplate (studio shot). The white background was not added by accident. – aliasguru Nov 16 '16 at 15:26 • not sure why this has been downvoted, thanks for the answer still – aliasguru Nov 16 '16 at 20:56 • (I'm not sure either... oh well) In that case, you should add the white back plate last. Use one alpha-over to combine the two images, then use another alpha over to put the image over the white. – Matt Nov 17 '16 at 14:12 • I've tried that already, makes no difference. The answer which Gez gave however is absolutely correct. It has to do with the way alpha operations are mathematically defined, and Alpha Over in my case was simply a no-go. – aliasguru Nov 17 '16 at 14:55 • Interesting... Glad you got it sorted, anyhow. – Matt Nov 18 '16 at 21:57	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.4061400294303894, "perplexity": 1130.3802820437318}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-10/segments/1581875144708.87/warc/CC-MAIN-20200220070221-20200220100221-00088.warc.gz"}
https://projecteuclid.org/euclid.die/1356059714	## Differential and Integral Equations ### Subcritical pseudodifferential equation on a half-line with nonanalytic symbol Elena I. Kaikina #### Abstract We study nonlinear pseudodifferential equations on a half-line with a nonanalytic symbol \begin{equation} \left\{ \begin{array}{c} \partial _{t}u+\mathbb{K}u=\lambda \left\vert u\right\vert ^{\sigma }u,\text{ }x\in \mathbf{R}^{+},\text{ }t>0, \\ u\left( 0,x\right) =u_{0}\left( x\right) \text{, }x\in \mathbf{R}^{+}, \end{array} \right. \end{equation} where $0<$ $\sigma <1,$ $\lambda \in \mathbf{R}$ and \begin{equation} \mathbb{K}u=\frac{1}{2\pi i}\theta (x)\int_{-i\infty }^{i\infty }e^{px}K(p) \widehat{u}(t,p)dp,\qquad K(p)=\frac{p^{2}}{p^{2}-1}. \end{equation} The aim of this paper is to prove the global existence of solutions to the initial-boundary-value problem and to find the main term of the asymptotic representation of solutions in subcritical case, when the nonlinear term of equation has the time decay rate less than that of the linear terms. #### Article information Source Differential Integral Equations, Volume 18, Number 12 (2005), 1341-1370. Dates First available in Project Euclid: 21 December 2012	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9919674396514893, "perplexity": 2127.0626910696733}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-39/segments/1537267158001.44/warc/CC-MAIN-20180922005340-20180922025740-00374.warc.gz"}
https://www.neetprep.com/question/27181-DNA-content-onion-tip-cell-C-end-M-phase-wouldbe-its-DNA-content-end-S-phasea-Cb-Cc-Cd-C?courseId=20	• Subject: ... • Topic: ... If the DNA content of an onion tip cell is 2C at the end of M phase, what would be its DNA content at the end of S phase? (a) C (b) 2C (c) 3C (d) 4C	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8288723826408386, "perplexity": 8976.36669973883}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-18/segments/1555578528058.3/warc/CC-MAIN-20190419201105-20190419223105-00409.warc.gz"}
http://mathhelpforum.com/trigonometry/8084-trig-question-finding-all-solutions.html	# Math Help - Trig question finding all solutions 1. ## Trig question finding all solutions what is the best way to find all the solutions of sin x-1=0, with the answer in A+Bkpi, where A=? with 0<A<pi where B=? and k is any integer Thankx Keith Stevens 2. Originally Posted by kcsteven what is the best way to find all the solutions of sin x-1=0, with the answer in A+Bkpi, where A=? with 0<A<pi where B=? and k is any integer Thankx Keith Stevens There is no such x, $0 < x < \pi$. $sin(x) - 1 = 0$ $sin(x) = 1$ For what values of x is sin(x) = 1? $x = 0, \pi$ Neither of which is in your indicated domain. -Dan	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 4, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9423078894615173, "perplexity": 3767.2164345819438}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-52/segments/1418802769709.84/warc/CC-MAIN-20141217075249-00163-ip-10-231-17-201.ec2.internal.warc.gz"}
https://www.physicsforums.com/threads/easy-domain.225092/	# Easy Domain 1. Mar 29, 2008 ### Calixto What would the domain of y = sqrt(cosx) be in mathematical terms. I know that it is all the reals that lie in the first and fourth quadrant of the unit circle, but how would you express that in mathematical terms? 2. Mar 29, 2008 ### nicksauce Something like $$D=\{x\|x\in[\frac{(4n-1)\pi}{2},\frac{(4n+1)\pi}{2}]\}$$ where n is any integer 3. Mar 30, 2008 ### unplebeian You first need to define the domain of x. If x is +60 for example then cos(x)>0 but if it is -60, then it is <0. sqrt of that is an imaginary number which is not defined. So basically for x>0 domain is (0,1) I would like to know how Calixto got his answer as I may be wrong. Similar Discussions: Easy Domain	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9262188673019409, "perplexity": 1305.1971115656427}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-26/segments/1498128320669.83/warc/CC-MAIN-20170626032235-20170626052235-00524.warc.gz"}
https://arxiv-export-lb.library.cornell.edu/abs/2109.10426?context=math.CA	math.CA (what is this?) # Title: Stability region and critical delay Abstract: The location of roots of the characteristic equation of a linear delay differential equation (DDE) determines the stability of the linear DDE. However, by its transcendency, there is no general criterion on the contained parameters for the stability. Here we mainly concentrate on the study of a simple transcendental equation $()$ $z + a - w \mathrm{e}^{-\tau z} = 0$ with coefficients of real $a$ and complex $w$ and a delay parameter $\tau > 0$ to tackle this transcendency brought by delay. The consideration is twofold: (i) to give the stability region in the parameter space for Eq.~$()$ by using the critical delay and (ii) to compare this with a graphical method (so-called the method of D-partitions) by combining with the delay sequence obtained by conditions for purely imaginary roots. By (i), we obtain another proof of Hayes' and Sakata's results, which reveals the nature of imaginary $w$ case in Eq.~$(*)$. By (ii), we propose a method combining the analytic one and geometric one. This combination is important because it will be helpful in studying characteristic equations having higher-dimensional parameters. Comments: 49 pages, 8 figures Subjects: Dynamical Systems (math.DS); Classical Analysis and ODEs (math.CA) MSC classes: Primary 34K06, 34K08, 34K20, Secondary 34K35, 37C75, 37N35 Cite as: arXiv:2109.10426 [math.DS] (or arXiv:2109.10426v2 [math.DS] for this version) ## Submission history From: Junya Nishiguchi [view email] [v1] Tue, 21 Sep 2021 20:13:58 GMT (28kb) [v2] Tue, 28 Jun 2022 13:07:57 GMT (35kb) Link back to: arXiv, form interface, contact.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.537377119064331, "perplexity": 1549.5495430468793}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-27/segments/1656103671290.43/warc/CC-MAIN-20220630092604-20220630122604-00684.warc.gz"}
http://mathhelpforum.com/number-theory/67606-eulers-totient-function.html	1. Eulers totient function Hi, I need to show that $$11^{40} + 33^{40} + 51^{40} + 97^{40}$$ is 4 in $$Z_{100}$$ using the totient function. The problem as i see it, is that 100 is not a prime number. i could of course go the long way $$(11^{2})^{20} = (21^{2})^{10}$$and so forth but that's a bit tedious... /Jones 2. Note, $\phi (100) = 40$ thus if $\gcd(a,100) = 1$ then $a^{\phi(100)} = a^{40} \equiv 1 (\bmod 100)$. Then, $\gcd(11,100) = \gcd(33,100) = \gcd(51,100) = \gcd(97,100) = 1$. Thus, $11^{40}+33^{40}+51^{40} + 97^{40} \equiv 1+1+1+1 = 4(\bmod 100)$. 3. It doesnt have to be prime if you know the zeta function, the two numbers just have to have a gcd of 1. 4. Originally Posted by ThePerfectHacker Note, $\phi (100) = 40$ thus if $\gcd(a,100) = 1$ then $a^{\phi(100)} = a^{40} \equiv 1 (\bmod 100)$. Then, $\gcd(11,100) = \gcd(33,100) = \gcd(51,100) = \gcd(97,100) = 1$. Thus, $11^{40}+33^{40}+51^{40} + 97^{40} \equiv 1+1+1+1 = 4(\bmod 100)$. Thank you, how would this be different if we had for example $$25^{40}$$ when the gcd is not 1 5. You would have to treat numbers like 2, 5, 25, 26, ... as special cases and work them out by hand.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 10, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9390052556991577, "perplexity": 165.05576931134289}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-30/segments/1500549429548.55/warc/CC-MAIN-20170727222533-20170728002533-00681.warc.gz"}
http://math.stackexchange.com/questions/88916/correspondences-between-borel-algebras-and-topological-spaces/89344	# Correspondences between Borel algebras and topological spaces Though tangentially related to another post on MathOverflow (here), the questions below are mainly out of curiosity. They may be very-well known ones with very well-known answers, but... Suppose $\Sigma$ is a sigma-algebra over a set, $X$. For any given topology, $\tau$, on $X$ denote by $\mathfrak{B}_X(\tau)$ the Borel algebra over $X$ generated by $\tau$. Question 1. Does there exist a topology, $\tau$, on $X$ such that $\Sigma = \mathfrak{B}_X(\tau)$? If the answer to the previous question is affirmative, it makes sense to ask for the following too: Question 2. Denote by ${\frak{T}}_X(\Sigma)$ the family of all topologies $\tau$ on $X$ such that $\Sigma = \mathfrak{B}_X(\tau)$ and let $\tau_X(\Sigma) := \bigcap_{\tau \in {\frak{T}}_X(\Sigma)} \tau$. Is $\Sigma = \mathfrak{B}_X({\frak{T}}_X(\Sigma))$? - A comment on Question 1: If $\kappa_1<\kappa_2$ are uncountable cardinals, $X$ is a set with cardinality $\kappa_2$, and $\Sigma$ is the set of subsets $S$ of $X$ such that $S$ or $X\setminus S$ has cardinality at most $\kappa_1$, then can $\Sigma$ be the $\sigma$-algebra generated by a topology? – Jonas Meyer Dec 7 '11 at 4:02 @Jonas: Can’t you simply take $\tau$ to be $\{\varnothing\}\cup\{V\subseteq X:\|X\setminus V\|\le\kappa_1\}$? – Brian M. Scott Dec 7 '11 at 7:13 OK, elephant in the room: assuming choice, the Lebesgue sigma-algebra on $\mathbb{R}$ is probably not a Borel sigma-algebra. Of course this makes problem 1 into one that depends on your set theory since word on the street is there exist models of ZF in which all subsets of $\mathbb{R}$ are measureable. – Mike F Dec 7 '11 at 8:03 @Mike, I posted an answer arguing that the Lebesgue algebra is not a counterexample. – JDH Dec 7 '11 at 19:56 George, can you post a proof that your counterexample is a counterexample? I don't quite see it yet... – JDH Dec 8 '11 at 0:07 This is a great question. I am posting not an answer to the question, but an answer to the comment posted by Mike about a proposed counterexample, the elephant in the room. Theorem. The elephant in the room is not a counterexample. That is, the $\sigma$-algebra of Lebesgue measurable sets is the Borel algebra of the topology consisting of all sets of the form $O-N$, where $O$ is open in the usual topology and $N$ has measure $0$. Proof. Note that the empty set and the whole of $\mathbb{R}$ have the desired form. Next, note that sets of that form are closed under finite intersection, since $(O-N)\cap(U-M)=(O\cap U)-(N\cup M)$. Next, I claim that they are closed under countable unions. This is because $\bigcup_i (O_i-N_i) = (\bigcup_i O_i)-N$, where $N$ is a certain subset of $\bigcup_iN_i$, which is still measure $0$ since this is a countable union. Next, note that it is closed under arbitrary unions in the case where the open set is the same, $\bigcup_i (O-N_i)$, since this is just the same as $O-(\bigcap_i N_i)$, which is $O$ minus a smaller null set. Finally, since we have a countable basis for the usual topology, using rational intervals, say, it follows now that my sets are closed under arbitrary unions, since for any sized union, we may rewrite it using basic open sets minus null sets, and then group together all the terms arising for each basic open set as a single term, thereby reducing the entire union to a countable union, which we've argued still has the desired form. Thus, the sets of the form $O-N$ do indeed form a topology, and this topology is clearly contained within the Lebesgue algebra. Furthermore, the Borel algebra generated by my collection of sets includes all measure zero sets, as well as all open sets, and so it is the same as the algebra of all Lebesgue measurable sets. QED - Thanks for the explaining this. I'm not sure how exactly this came about, but I've been walking around for a few years now thinking that the Lebesgue $\sigma$-algebra was somehow bigger than the completion of the Borel $\sigma$-algebra (wrt Lebesgue measure) - but I guess they are the same thing! – Mike F Dec 8 '11 at 6:42 ..yet somehow I was also aware that, when $S \subset \mathbb{R}$ is measureable, there exist $\mathscr{G}_\delta$ $G$ and $\mathscr{F}_\sigma$ $F$ such that $F \subset S \subset G$ and $G - F$ has measure zero. A couple of contradictory beliefs which somehow never bumped into each other. – Mike F Dec 8 '11 at 6:49 @JDH. It's your answer that is great. – Salvo Tringali Dec 9 '11 at 12:58 I think that I can answer the second question. For each point $p \in \mathbb{R}$, let $\tau_p$ be the topology on $\mathbb{R}$ consisting of $\varnothing$ together with all the standard open neighbourhoods of $p$. Unless I've made some mistake, the Borel sigma-algebra generated by $\tau_p$ is the standard one. However, $\bigcap_{p \in \mathbb{R}} \tau_p$ is the indiscrete topology on $\mathbb{R}$. - I can't see why the Borel sets would be the same as the standard one. – Asaf Karagila Dec 6 '11 at 20:45 Asaf, it's because $\{p\}$ is Borel in $\tau_p$, arising from the intersection of nested intervals centered on $p$. Once you've got $\{p\}$, then you can get all the open sets not containing $p$ simply by subtracting, and so you get all the ordinary open sets. Thus, the Borel sets of $\tau_p$ include all the usual Borel sets. (And of course, it is included in this, so they are equal.) – JDH Dec 6 '11 at 21:13 @JDH: Ah, I figured it was something related to that. I did not keep in mind that we have the standard topology in the background; rather than just a continuum-sized set. – Asaf Karagila Dec 6 '11 at 21:17 @Mike. So nice! I'm editing the OP to update it and add that Q2 was replied in the negative. – Salvo Tringali Dec 6 '11 at 21:41 @JDH: Well $\{p\}$ isn't quite the whole story since subtracting that only gives you standard open sets having $p$ as a 2-sided limit point. But you can also get any closed interval containing $p$ by intersecting nested open intervals - and subtracting these should give the rest of the standard open sets (or at least the open intervals omitting $p$ which is enough). – Mike F Dec 6 '11 at 23:48 For Q1. How about this. $X = \{0,1\}^A$ for uncountable $A$, and $\Sigma$ is the product $\sigma$-algebra. So each element of $\Sigma$ depends on only countably many coordinates. Now we just need a proof that this cannot be the Borel algebra of any topology. - That is indeed true. I was about to post something along these lines and, in fact, I think you can convert it to a sigma algebra on A itself rather than on $2^A$. – George Lowther Dec 7 '11 at 21:38 I think you can show that there must exist an $x\in X$ such that $\{x\}$ is closed. But, $\{x\}\not\in\Sigma$. – George Lowther Dec 7 '11 at 21:49 @George: Of course this needs more work to show that... Our space is $T_0$ but not $T_1$. – GEdgar Dec 7 '11 at 22:19 Yes, I was too quick there. What I said is not true in the case where A is countably infinite, because $2^A$ is isomorphic (as a measurable space) to the reals with Borel sigma-algebra generated by the topology $\{(x,\infty):x\in R\}$, for which no $\{x\}$ is closed. – George Lowther Dec 8 '11 at 1:24 EDIT: It's best just to ignore this nonsensical post. The product space mentioned in the answer by Gerald Edgar does not provide a counterexample. The product $\sigma$-algebra is determined by countably many coordinate, the product topology by finitely many coordinates. A set determined by countably many coordiantes is a countable intersection of sets determined by finitely many coordinates. Remark: This answer contained a flawed "proof" that the answer to the first question is yes. I've edited it. - If you still claim my space $X = \{0,1\}^A$ is not a counterexample, you need more explanation. Certainly that product sigma-algebra is not the Borel algebra for the product topology. But is it the Borel algebra for some other topology? That is the question! – GEdgar Dec 24 '11 at 17:16 You are right of course, the Borel sigma-algebra is too large. I'm sorry. Explaining what my confusion was would take more than the number of characters left... – Michael Greinecker Dec 27 '11 at 0:13	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9577801823616028, "perplexity": 196.93584913182028}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-48/segments/1448398446500.34/warc/CC-MAIN-20151124205406-00232-ip-10-71-132-137.ec2.internal.warc.gz"}
https://www.molpro.net/info/2015.1/doc/manual/node480.html	## 37.3 DFT-SAPT It is of crucial importance to account for the intramolecular correlation effects of the individual SAPT terms since Hartree-Fock theory often yields poor first- and second-order electrostatic properties. While this can be done using many-body perturbation theory [1] (in a double perturbation theory ansatz) a more efficient way is to use static and time-dependent DFT theory. This variant of SAPT, termed as DFT-SAPT [2-6], has in contrast to Hartree-Fock-SAPT the appealing feature that the polarisation terms ( , , ) are potentially exact, i.e. they come out exactly if the exact exchange-correlation (xc) potential and the exact (frequency-dependent) xc response kernel of the monomers were known. On the other hand, this does not hold for the exchange terms since Kohn-Sham theory can at best give a good approximation to the exact density matrix of a many-body system. It has been shown [6] that this is indeed the the case and therefore DFT-SAPT has the potential to produce highly accurate interaction energies comparable to high-level supermolecular many-body perturbation or coupled cluster theory. However, in order to achieve this accuracy, it is of crucial importance to correct the wrong asymptotic behaviour of the xc potential in current DFT functionals [3-5]. This can be done by using e.g.: {ks,lda; asymp,<shift>} which activates the gradient-regulated asymptotic correction approach of Grüning et al. (J. Chem. Phys. 114, 652 (2001)) for the respective monomer calculation. The user has to supply a shift parameter ( ) for the bulk potential which should approximate the difference between the HOMO energy ( ) obtained from the respective standard Kohn-Sham calculation and the (negative) ionisation potential of the monomer (): (57) This method accounts for the derivative discontinuity of the exact xc-potential and that is missing in approximate ones. Note that this needs to be done only once for each system. (See also section 37.7.2 for an explicit example). Concerning the more technical parameters in the DFT monomer calculations it is recommended to use lower convergence thresholds and larger intergration grids compared to standard Kohn-Sham calculations. molpro@molpro.net 2019-03-18	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9085679054260254, "perplexity": 898.9586677401452}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-13/segments/1552912201953.19/warc/CC-MAIN-20190319093341-20190319115341-00322.warc.gz"}
https://blog.awill.me/2010/09/16/adventures-at-the-fuel-pump/	blog.awill.me So, since someone who shall remain nameless (only be known by the letters kdr) said my blog was too boring and geeky, I’ve decided to post what happened to me yesterday while trying to fill up with fuel. This happened at the Conoco in American Fork, UT. I get off work and drive to the nearest petrol station. I pull out my credit card, swipe, and begin fueling. I’ve only put in about a gallon when a woman (dressed in Conoco employee uniform) comes out and starts yelling that I haven’t paid for gas. I tell her that I swiped my card. She repeats herself, getting frustrated with me, and tells me I need to come inside to pay. I’m obviously a little annoyed at this point, as I was in a bit of a hurry. I go inside, and the woman explains that the guy on the pump next to me had pre-paid $15 for fuel, and by some accident, they’d allotted the money to my pump by mistake, and I’d used his fuel. She then proceeds to tell me that I owe this random guy$3.07. She asks me to pay him. I obviously refuse. I then tell the lady that I was going to pay with a credit card. I explain that I bought the fuel from Conoco, and will be paying Conoco with my credit card. The Conoco employee says she doesn’t know how to fix the problem. The only solution is for me to pay the guy $3.07, the guy then pumps the remaining$11.93, then pays Conoco my $3.07 and pumps that. She claimed there was no other way, and asks me if I can drive to an ATM to get the money. Being so extremely complicated (note the sarcasm), I explain that the guy can pump the remaining$11.93 and then I can do a pre-pay of $3.07 with my credit card, which he can then pump as well. Then everyone’s paid and everyone’s happy (except for the fact that I’ve just wasted 10 minutes of my life that I’ll never get back.) Sounds simple, right? Wrong. Everything goes according to plan. The guy pumps the remaining$11.93. I then pre-pay for $3.07. But, then, rather than send my$3.07 to the guy’s pump, the lady send the $3.07 to a different pump, and the EXACT SAME THING HAPPENS AGAIN. She darts out toward the pumps and starts screaming at this poor woman “You haven’t paid, you haven’t paid. Stop pumping fuel.” I’m not so much fed up at this point, I’m just shocked at the sheer incompetence. The woman asks me to wait until this is all sorted out. I kindly explain that I have now paid for my$3.07 of fuel, and that I’m free to leave. I also mention that I still only pumped 1 gallon of fuel, but that I will be using that gallon to get to a different gas station. I leave. Categories	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.4359613060951233, "perplexity": 2031.0234166886146}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-39/segments/1631780057033.33/warc/CC-MAIN-20210920070754-20210920100754-00434.warc.gz"}
https://link.springer.com/article/10.1007/s00220-015-2479-5	Communications in Mathematical Physics , Volume 343, Issue 2, pp 651–700 # Stochastic Higher Spin Vertex Models on the Line Article ## Abstract We introduce a four-parameter family of interacting particle systems on the line, which can be diagonalized explicitly via a complete set of Bethe ansatz eigenfunctions, and which enjoy certain Markov dualities. Using this, for the systems started in step initial data, we write down nested contour integral formulas for moments and Fredholm determinant formulas for Laplace-type transforms. Taking various choices or limits of parameters, this family degenerates to many of the known exactly solvable models in the Kardar–Parisi–Zhang universality class, as well as leads to many new examples of such models. In particular, asymmetric simple exclusion process, the stochastic six-vertex model, q-totally asymmetric simple exclusion process and various directed polymer models all arise in this manner. Our systems are constructed from stochastic versions of the R-matrix related to the six-vertex model. One of the key tools used here is the fusion of R-matrices and we provide a probabilistic proof of this procedure. ## Keywords High Spin Exclusion Process Corwin Totally Asymmetric Simple Exclusion Process Vertex Weight These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves. ## References 1. ACQ11. Amir, G., Corwin, I., Quastel, J.: Probability distribution of the free energy of the continuum directed random polymer in 1 + 1 dimensions. Commun. Pure Appl. Math. 64(4), 466–537 (2011). arXiv:1003.0443 [math.PR] 2. Bar14. Barraquand, G.: A phase transition for q-TASEP with a few slower particles. 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Carinci, G., Giardina, C., Redig, F., Sasamoto, T.: A generalized asymmetric exclusion process with $${U_q(\mathfrak{sl}_2)}$$ stochastic duality (2014). arXiv:1407.3367 [math.PR] 16. Cor14. Corwin, I.: The q-Hahn Boson process and q-Hahn TASEP. Intern. Math. Res. Not. (2014). arXiv:1401.3321 [math.PR] 17. COSZ14. Corwin, I., O’Connell, N., Seppäläinen, T., Zygouras, N.: Tropical combinatorics and Whittaker functions. Duke J. Math. 163(3), 513–563 (2014). arXiv:1110.3489 [math.PR] 18. CP15. Corwin, I., Petrov, L.: The q-pushASEP: a new integrable model for traffic in 1 + 1 dimension. J. Stat. Phys. 160(4), 1005–1026 (2015). arXiv:1308.3124 [math.PR] 19. CSS14. Corwin, I., Seppäläinen, T., Shen, H.: The strict-weak lattice polymer (2014). arXiv:1409.1794 [math.PR] Faddeev, L.D.: How algebraic Bethe Ansatz works for integrable model. In: Les-Houches Lecture Notes (1996). arXiv:1407.3367 [math.PR] 21. FV13. Ferrari, P., Veto, B.: Tracy–Widom asymptotics for q-TASEP. Ann. Inst. Hen. Poin. 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Seppäläinen T.: Scaling for a one-dimensional directed polymer with boundary conditions. Ann. Probab. 40(1), 19–73 (2012) 37. SS10. Sasamoto, T., Spohn, H.: Exact height distributions for the KPZ equation with narrow wedge initial condition. Nucl. Phys. B 834(3), 523–542 (2010) arXiv:1002.1879 [cond-mat.stat-mech] 38. SS14. Sasamoto, T., Spohn, H.: Point-interacting Brownian motions in the KPZ universality class (2014). arXiv:1411.3142 [math.PH] 39. SW98. Sasamoto T., Wadati M.: Exact results for one-dimensional totally asymmetric diffusion models. J. Phys. A 31, 6057–6071 (1998) 40. TLD14. Thimothée T., Le Doussal P.: Log-gamma directed polymer with fixed endpoints via the replica Bethe Ansatz. J. Stat. Mech. 2014(10), P10018 (2014) 41. TW08. Tracy, C., Widom, H.: Integral formulas for the asymmetric simple exclusion process. Commun. Math. Phys. 279, 815–844 (2008). arXiv:0704.2633 [math.PR]. [Erratum: Commun. Math. Phys. 304, 875–878 (2011)] 42. TW09. Tracy, C., Widom, H.: Asymptotics in ASEP with step initial condition. Commun. Math. Phys. 290, 129–154 (2009). arXiv:0807.1713 [math.PR] 43. Vet14. Veto, B.: Tracy–Widom limit of q-Hahn TASEP (2014). arXiv:1407.2787 [math.PR]	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7678502202033997, "perplexity": 8484.478075993533}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-26/segments/1529267862929.10/warc/CC-MAIN-20180619115101-20180619135101-00228.warc.gz"}
http://mathhelpforum.com/calculus/118588-evaluate-definite-integral-print.html	# Evaluate the definite Integral • December 5th 2009, 12:51 AM zorro Evaluate the definite Integral Question : Evaluate $ \int_{-1}^{1} \ \frac{3 + sin^3 x}{1 + x^2} \ dx $ • December 5th 2009, 01:08 AM flyingsquirrel Quote: Originally Posted by zorro Question : Evaluate $ \int_{-1}^{1} \ \frac{3 + sin^3 x}{1 + x^2} \ dx $ $ \int_{-1}^{1} \frac{3 + \sin^3 x}{1 + x^2} \ \mathrm{d}x=3\int_{-1}^{1} \frac{1}{1 + x^2} \ \mathrm{d}x+\int_{-1}^{1} \frac{\sin^3 x}{1 + x^2} \ \mathrm{d}x $ Hint : note that $x\mapsto \frac{\sin^3 x}{1 + x^2}$ is odd. • December 8th 2009, 12:27 AM zorro Stuck again !!! Quote: Originally Posted by flyingsquirrel $ \int_{-1}^{1} \frac{3 + \sin^3 x}{1 + x^2} \ \mathrm{d}x=3\int_{-1}^{1} \frac{1}{1 + x^2} \ \mathrm{d}x+\int_{-1}^{1} \frac{\sin^3 x}{1 + x^2} \ \mathrm{d}x $ Hint : note that $x\mapsto \frac{\sin^3 x}{1 + x^2}$ is odd. I am able to integrate the first term but not the last one = $3 \int_{-1}^{1} \frac{1}{1 + x^2} + \int_{-1}^{1} \frac{sin^3 x}{1 + x^2}$ = $I_1 + I_2$ $I_1$ = $3 \left[ tan^{-1} (1) - tan^{-1} (-1) \right] + c_1$ = $3 \left[ tan^{-1} (1) - tan^{-1} (-1) \right] + c_1$ = $3 \left[ \frac{\pi}{4} +\frac{\pi}{4} \right] + c_1$ = $3 \left[ \frac{2 \pi}{4} \right] + c_1$ = $\left[ \frac{6 \pi}{4} \right] + c_1$ $I_2$ = $\int_{-1}^{1} \frac{sin^3 x}{1 + x^2}$ $dx_2$ = $\int_{-1}^{1} \frac{sin^3 x}{1 + x^2}$ $dx_2$ I am stuck here!!!!!...... • December 8th 2009, 01:59 AM dedust Quote: Originally Posted by flyingsquirrel Hint : note that $x\mapsto \frac{\sin^3 x}{1 + x^2}$ is odd. so $\int_{-1}^{1} \frac{\sin^3 x}{1 + x^2} \ \mathrm{d}x = 0$ • December 8th 2009, 02:03 AM flyingsquirrel Quote: Originally Posted by zorro $I_1$ = $3 \left[ tan^{-1} (1) - tan^{-1} (-1) \right] + c_1$ There is no need to add a constant since $\int_{-1}^1\frac{1}{1+x^2}\,\mathrm{d}x$ is a definite integral. Quote: Originally Posted by zorro = $\left[ \frac{6 \pi}{4} \right] + c_1$ $\frac{6\pi}{4}=\frac{3\times 2\pi}{2\times 2}=\frac{3\pi}{2}$ Quote: Originally Posted by zorro $I_2$ = $\int_{-1}^{1} \frac{sin^3 x}{1 + x^2}$ $dx_2$ $I_2 = \int_{-1}^0\frac{\sin^3x}{1+x^2}\,\mathrm{d}x + \int_0^1\frac{\sin^3x}{1+x^2}\,\mathrm{d}x$ Substitute $x=-t$ ( $\implies t=-x$ and $\mathrm{d}t=-\mathrm{d}x$) in the first integral : $\int_{-1}^0\frac{\sin^3x}{1+x^2}\,\mathrm{d}x =-\int_{1}^0\frac{\sin^3(-t)}{1+(-t)^2}\,\mathrm{d}t=\int_0^1\frac{-\sin^3t}{1+t^2}\,\mathrm{d}t=-\int_0^1\frac{\sin^3t}{1+t^2}\,\mathrm{d}t$ Thus $I_2 = -\int_0^1\frac{\sin^3t}{1+t^2}\,\mathrm{d}t+\int_0^ 1\frac{\sin^3x}{1+x^2}\,\mathrm{d}x=0.$ This is a special case of a more general result: Let $f:\mathbb{R}\to\mathbb{R}$ be an odd function and let $A$ be a real number. Then $\int_{-A}^Af(t)\,\mathrm{d}t=0.$ Edit : Quote: Originally Posted by dedust so $\int_{-1}^{1} \frac{\sin^3 x}{1 + x^2} \ \mathrm{d}x = 0$ Yes ! • December 8th 2009, 02:17 AM zorro Thanks u very much Thank u all very much for helping me(Bow) • December 8th 2009, 05:48 AM Krizalid as for that property about the odd function, we also require that $f$ must be integrable there. • December 8th 2009, 12:01 PM zorro what do u mean by that Quote: Originally Posted by Krizalid as for that property about the odd function, we also require that $f$ must be integrable there. could u please explain it in non mathematical terms ,as i m not that bright?? • December 21st 2009, 03:30 PM zorro Got it Quote: Originally Posted by zorro could u please explain it in non mathematical terms ,as i m not that bright?? Thanks u all for helping (Beer)	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 41, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9349957704544067, "perplexity": 2237.988376845269}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-22/segments/1433195035744.13/warc/CC-MAIN-20150601214355-00036-ip-10-180-206-219.ec2.internal.warc.gz"}
https://quant.stackexchange.com/questions/55516/confusion-about-optimal-choices-with-exotic-options	# Confusion about optimal choices with exotic options With exotic options, holders usually face choices at certain times. In my understanding, the price of the option is determined by assuming the optimal choice is taken and computing the discounted expectation of the payoff under the risk neutral measure with backward induction. My question is if I hold such options, how does taking the optimal choice benefit me? Such optimal choices are optimal under the risk neutral measure, so how does taking such choices imply/guarantee (even probabilistically) anything under the actual measure? If I take the optimal choice as determined by the pricing model, that would maximize the arbitrage-free price of the option that I am holding, but does that bear any optimality in the actual world? Does that tend to lead to a higher P/L? Say the option has intrinsic value $$x$$, extrinsic value $$y$$, and I just happen to hold this option, not for hedging purposes and without any particular view on the underlying. How can I benefit from the optionality/extrinsic value? I understand that I would lose some of the extrinsic value if I don't follow the optimal choice, but that's just a theoretical construct, where would I see the manifestation of this "loss of value"? Consider a vanilla european option. The optimal strategy in the risk neutral measure is to exercise if $$S(T)>K$$. (because in the risk neutral world, I value my payoff at its expectation, which at that point is the payoff itself. At time T, if $$S(T)-K$$ is positive, I will take it over not exercising, which is a payoff of 0. This is of course also optimal in the real world - more money is better than less money. So my 'optimal exercise strategy' matches. The manifestation of loss in value is a PnL leak. Consider the same example as above. Say $$S(T)>K$$ but you don't exercise your option at all: so you've just paid something for the option, but sub-optimal exercise strategy means that you've got nothing. This is an extreme example of course but you see the idea. The same idea extends to exotics. Consider a Bermudan with 2 exercise dates. Denote by E the immediate exercise value at the first date, and by C the continuation value. Denote by $$w$$ the state of the world, and $$T$$ denotes the 1st exercise date, and $$T_ex$$ denote the date I exercise my option on (which is random). Let $$A={w:E(w)>C(w)}$$. Then $$Pr[(T_ex=T)\|A]=1$$ in the risk neutral measure. Since real world and risk neutral measure are equivalent (they agree on what's possible and not), we get $$Pr[(T_ex=T)\|A]=1$$ in the real world. This tells you that you will exercise in the real world exactly when you exercise in the 'risk neutral measure'. Which tells you that the 'optimal strategy' is exactly the same. Appendix: The proof of conditional probabilities being the same in equivalent measures is better thought of by considering (assume $$Pr(A)>0$$ and $$Pr(B)>0$$) say $$Pr(B\|A)=0$$ in the R.N. measure. Then $$Pr(B,A)=0 => Pr(B,A)=0$$ in the real world measure. As $$Pr(A)>0$$, we must have $$Pr(B\|A)=0$$ in the real world measure too.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 17, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.940972089767456, "perplexity": 554.8916297896764}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-25/segments/1623487616657.20/warc/CC-MAIN-20210615022806-20210615052806-00346.warc.gz"}
http://mathhelpforum.com/calculus/92311-trigonometric-limit-print.html	# Trigonometric limit? • Jun 9th 2009, 08:20 AM fardeen_gen Trigonometric limit? Evaluate: $\lim_{x\rightarrow 0} \left(1^{\frac{1}{\sin^2 x}} + 2^{\frac{1}{\sin^2 x}} + 3^{\frac{1}{\sin^2 x}} + \mbox{...} + n^{\frac{1}{\sin^2 x}}\right)^{\sin^2 x}$ • Jun 9th 2009, 11:14 AM sinewave85 Quote: Originally Posted by fardeen_gen Evaluate: $\lim_{x\rightarrow 0} \left(1^{\frac{1}{\sin^2 x}} + 2^{\frac{1}{\sin^2 x}} + 3^{\frac{1}{\sin^2 x}} + \mbox{...} + n^{\frac{1}{\sin^2 x}}\right)^{\sin^2 x}$ It would seem that: $\lim_{x\rightarrow 0+} \left(1^{\frac{1}{\sin^2 x}} + 2^{\frac{1}{\sin^2 x}} + 3^{\frac{1}{\sin^2 x}} + \mbox{...} + n^{\frac{1}{\sin^2 x}}\right)^{\sin^2 x} = (+\infty)^{0} = 1$ and $\lim_{x\rightarrow 0-} \left(1^{\frac{1}{\sin^2 x}} + 2^{\frac{1}{\sin^2 x}} + 3^{\frac{1}{\sin^2 x}} + \mbox{...} + n^{\frac{1}{\sin^2 x}}\right)^{\sin^2 x} = (-\infty)^{0} = 1$ so $\lim_{x\rightarrow 0} \left(1^{\frac{1}{\sin^2 x}} + 2^{\frac{1}{\sin^2 x}} + 3^{\frac{1}{\sin^2 x}} + \mbox{...} + n^{\frac{1}{\sin^2 x}}\right)^{\sin^2 x} = 1$ • Jun 9th 2009, 11:32 AM Moo Quote: Originally Posted by sinewave85 It would seem that: $\lim_{x\rightarrow 0+} \left(1^{\frac{1}{\sin^2 x}} + 2^{\frac{1}{\sin^2 x}} + 3^{\frac{1}{\sin^2 x}} + \mbox{...} + n^{\frac{1}{\sin^2 x}}\right)^{\sin^2 x} = (+\infty)^{0} = 1$ But this is not defined (Worried) Quote: and $\lim_{x\rightarrow 0-} \left(1^{\frac{1}{\sin^2 x}} + 2^{\frac{1}{\sin^2 x}} + 3^{\frac{1}{\sin^2 x}} + \mbox{...} + n^{\frac{1}{\sin^2 x}}\right)^{\sin^2 x} = (-\infty)^{0} = 1$ How can something positive have a negative limit ? Quote: so $\lim_{x\rightarrow 0} \left(1^{\frac{1}{\sin^2 x}} + 2^{\frac{1}{\sin^2 x}} + 3^{\frac{1}{\sin^2 x}} + \mbox{...} + n^{\frac{1}{\sin^2 x}}\right)^{\sin^2 x} = 1$ ... • Jun 9th 2009, 11:36 AM sinewave85 Quote: Originally Posted by Moo But this is not defined (Worried) How can something positive have a negative limit ? ... Very sorry -- I forgot that $\infty^{0}$ was undefined. Thanks for catching that, Moo. I would hate to lead someone astray. • Jun 9th 2009, 09:34 PM fardeen_gen How do we deal with $\infty^{0}$ forms? This problem has been giving me a headache. • Jun 10th 2009, 03:55 AM Ruun $\frac{\sin^2(x)}{\sin^2(x)} (\frac{1}{\sin^2(x)}+\frac{1}{2\sin^2(x)}+ \mbox(...) +\frac{1}{n \sin^2(x)})^{\sin^2(x)}=\frac{1}{\sin^2(x)}(H_n)^{ \sin^2(x)}=L$ $ln (L) = ln(H_n)$ Harmonic number - Wikipedia, the free encyclopedia • Jun 10th 2009, 04:32 AM Isomorphism Quote: Originally Posted by fardeen_gen Evaluate: $\lim_{x\rightarrow 0} \left(1^{\frac{1}{\sin^2 x}} + 2^{\frac{1}{\sin^2 x}} + 3^{\frac{1}{\sin^2 x}} + \mbox{...} + n^{\frac{1}{\sin^2 x}}\right)^{\sin^2 x}$ Using the fact that $\sin x \approx x$, for small x, we can write: $\lim_{x\rightarrow 0} \left(1^{\frac{1}{\sin^2 x}} + 2^{\frac{1}{\sin^2 x}} + 3^{\frac{1}{\sin^2 x}} + \mbox{...} + n^{\frac{1}{\sin^2 x}}\right)^{\sin^2 x} =$ $\lim_{t \rightarrow \infty} \left(1^{t^2} + 2^{t^2} + 3^{t^2} + \mbox{...} + n^{t^2}\right)^{\frac1{t^2}}$ Taking logs and apply LHospital's rule, we have to evaluate $\lim_{t \rightarrow \infty} \frac{\log \left(1^{t^2} + 2^{t^2} + 3^{t^2} + \mbox{...} + n^{t^2}\right)}{t^2}$ to get $\log n!$, Finally the answer is n! • Jun 11th 2009, 11:40 AM Random Variable Quote: Originally Posted by Isomorphism Using the fact that $\sin x \approx x$, for small x, we can write: $\lim_{x\rightarrow 0} \left(1^{\frac{1}{\sin^2 x}} + 2^{\frac{1}{\sin^2 x}} + 3^{\frac{1}{\sin^2 x}} + \mbox{...} + n^{\frac{1}{\sin^2 x}}\right)^{\sin^2 x} =$ $\lim_{t \rightarrow \infty} \left(1^{t^2} + 2^{t^2} + 3^{t^2} + \mbox{...} + n^{t^2}\right)^{\frac1{t^2}}$ Taking logs and apply LHospital's rule, we have to evaluate $\lim_{t \rightarrow \infty} \frac{\log \left(1^{t^2} + 2^{t^2} + 3^{t^2} + \mbox{...} + n^{t^2}\right)}{t^2}$ to get $\log n!$, Finally the answer is n! After one application of L'Hospital's rule, I get $\lim_{t \to \infty} \frac {\ln(1)1^{t^{2}} + \ln(2)2^{t^{2}} + \ln(3)3^{t^{2}} + ... + \ln(n)n^{t^{2}}}{1^{t^{2}} + 2^{t^{2}} + 3^{t^{2}} + ... + n^{t^{2}}}$ then it would appear you did the following $\lim_{t \to \infty} \frac {\big(\ln(1) +\ln(2) + \ln(3) + ... + \ln(n)\big)(1^{t^{2}} + 2^{t^{2}} + 3^{t^{2}} + ... + n^{t^{2}})}{ 1^{t^{2}} + 2^{t^{2}} + 3^{t^{2}} + ... + n^{t^{2}}}$ ? $= \lim_{t \to \infty} \ln(123...n)$ which would be correct if the previous step were correct What am I missing? • Jun 11th 2009, 09:38 PM Isomorphism Quote: Originally Posted by Random Variable After one application of L'Hospital's rule, I get $\lim_{t \to \infty} \frac {\ln(1)1^{t^{2}} + \ln(2)2^{t^{2}} + \ln(3)3^{t^{2}} + ... + \ln(n)n^{t^{2}}}{1^{t^{2}} + 2^{t^{2}} + 3^{t^{2}} + ... + n^{t^{2}}}$ then it would appear you did the following $\lim_{t \to \infty} \frac {\big(\ln(1) +\ln(2) + \ln(3) + ... + \ln(n)\big)(1^{t^{2}} + 2^{t^{2}} + 3^{t^{2}} + ... + n^{t^{2}})}{ 1^{t^{2}} + 2^{t^{2}} + 3^{t^{2}} + ... + n^{t^{2}}}$ ? $= \lim_{t \to \infty} \ln(123...n)$ which would be correct if the previous step were correct What am I missing? (Tmi) You are not missing anything...Its wrong and was hastily written(I applied $t \to 0$) Here is the solution: $\lim_{t \to \infty} \frac {\ln(1)1^{t^{2}} + \ln(2)2^{t^{2}} + \ln(3)3^{t^{2}} + ... + \ln(n)n^{t^{2}}}{1^{t^{2}} + 2^{t^{2}} + 3^{t^{2}} + ... + n^{t^{2}}}$ $= \lim_{t \to \infty} \dfrac {0 + \ln(2)\left(\frac2{n}\right)^{t^{2}} + \ln(3)\left(\frac3{n}\right)^{t^{2}} + ... + \ln(n)}{\left(\frac1{n}\right)^{t^{2}} + \left(\frac2{n}\right)^{t^{2}} + \left(\frac3{n}\right)^{t^{2}} + ... + 1}$ $=\ln(n)$	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 33, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9888268709182739, "perplexity": 3372.0109967496346}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-09/segments/1518891811795.10/warc/CC-MAIN-20180218081112-20180218101112-00522.warc.gz"}
https://asmedigitalcollection.asme.org/GT/proceedings-abstract/GT2019/58615/V04AT04A053/1066744?redirectedFrom=PDF	## Abstract Modern gas turbines usually adopt very lean premixed flames to meet the current strict law restrictions on nitric oxides emissions. In such devices, strong combustion instabilities and blow-off susceptibility often prevent from achieving a stable flame in leaner conditions. Numerical models to predict the lean blow-off in turbulent flames are essential to prevent such instabilities, but the simulation of blow-off still represents a challenge, requiring the appropriate modelling for the turbulence-chemistry interactions and the highly transient behaviour of the flame near the extinction limit. The present work explores the capabilities of the widely-used Flamelet Generated Manifold model in predicting the lean blow-off of a turbulent swirl-stabilized premixed flame within LES framework. An atmospheric premixed methane-air flame, experimentally studied at the University of Cambridge, is firstly analyzed in three operating conditions approaching blow-off to validate the numerical setup. An extended Turbulent Flame Closure (TFC) model, implemented within the FGM framework in Fluent to introduce the effect of stretch and heat loss on the flame, reproduces the evolution of the key flame characteristics. Then, the chosen setup is used to study the blow-off inception and the dynamics in two conditions with different flow rate. An accelerated numerical procedure with progressive step reductions of equivalence ratio is used to trigger the blow-off. The extinction equivalence ratio is predicted quite accurately, showing that the Extended TFC is suitable for the study of the blow-off, without an increase in computational cost. The validity of the model could be extended, allowing the study of lean blow-off in realistic conditions and complex flames of gas turbine combustors. This content is only available via PDF.	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8106809258460999, "perplexity": 2899.357992053838}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-40/segments/1664030335190.45/warc/CC-MAIN-20220928082743-20220928112743-00012.warc.gz"}
http://technet.microsoft.com/en-us/library/cc441748.aspx	# Cache performance counters Updated: February 1, 2011 Applies To: Forefront Threat Management Gateway (TMG) The following table lists the performance counters for the Forefront TMG cache. Performance counter Description Bytes Retrieved Rate from Disk Cache (KB/sec) The rate at which kilobytes of data are retrieved from the disk cache. Bytes Retrieved Rate from Memory Cache (KB/sec) The rate at which kilobytes of data are retrieved from the memory cache. Disk Cache Allocated Space (KB) The amount of space used for the disk cache (from the total disk space allocated for disk caching). Disk Failure Rate (Fail/sec) The number of I/O failures per second since the Firewall service started. An I/O failure occurs when Forefront TMG fails to read from or write to disk cache. Disk Write Rate (writes/sec) The number of writes to the disk cache, per second. Max URLs Cached The maximum number of URLs stored in the cache simultaneously since the Firewall service was started. Max URLs Cached Measures the maximum number of URLs that have been stored in the cache. Memory Cache Allocated Space (KB) The amount of space used for the memory cache (from the total memory allocated for memory caching). Memory Usage Ratio Percent (%) The amount of fetches from the memory cache, in proportion to the total fetches from the cache. Total Disk Failures The number of times since the Firewall service started that Forefront TMG failed to read from or write to disk cache, due to an I/O failure. Total URLs Cached The cumulative number of URLs stored in the cache. URL Commit Rate (URL/sec) The rate at which URLs are stored to the cache. URL Retrieve Rate from Disk Cache (URL/sec) URL Retrieve Rate from Memory Cache (URL/sec)	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.801867663860321, "perplexity": 12336.345483426938}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-41/segments/1410657137698.52/warc/CC-MAIN-20140914011217-00055-ip-10-234-18-248.ec2.internal.warc.gz"}
http://www.ck12.org/algebra/Checking-Solutions-to-Inequalities/lecture/One-Step-Inequalities/r1/	<img src="https://d5nxst8fruw4z.cloudfront.net/atrk.gif?account=iA1Pi1a8Dy00ym" style="display:none" height="1" width="1" alt="" /> Checking Solutions to Inequalities Substitute values for variables to check inequality solutions 0% Progress Practice Checking Solutions to Inequalities Progress 0% One-Step Inequalities Explains how to solve and graph inequality problems using a sample problem.	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8731003999710083, "perplexity": 28012.5441392}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-48/segments/1448398467979.1/warc/CC-MAIN-20151124205427-00308-ip-10-71-132-137.ec2.internal.warc.gz"}
https://www.h2knowledgecentre.com/content/conference746	1900 # Blast Wave from Bursting Enclosure with Internal Hydrogen-air Deflagration ### Abstract Most studies on blast waves generated by gas explosions have focused on gas explosions occurring in open spaces. However, accidental gas explosions often occur in confined spaces and the blast wave generates from a bursting vessel as a result of an increase in pressure caused by the gas explosion. In this study, blast waves from bursting plastic vessels in which gas explosions occurred are investigated. The flammable mixtures used in the experiments were hydrogen-air mixtures at several equivalence ratios and a stoichiometric methane-air mixture. The overpressures of the blast waves were generated by venting high-pressure gas in the enclosure and volumetric expansion with a combustion reaction. The measured intensities of the blast waves were greater than the calculated values resulting from high-pressure bursting without a combustion reaction. The intensities of the blast waves resulting from the explosions of hydrogen-air mixtures were much greater than those of the methane-air mixture. Keywords: Related subjects: Countries: /content/conference746 2015-10-19 2022-05-25 http://instance.metastore.ingenta.com/content/conference746 Supplements #### Blast wave from bursing enclosure with internal hydrogen-air deflagration This is a required field	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9012472629547119, "perplexity": 3541.3679363052192}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-21/segments/1652662577757.82/warc/CC-MAIN-20220524233716-20220525023716-00115.warc.gz"}
https://infoscience.epfl.ch/record/28071	## How Many Robots? Group Size and Efficiency in Collective Search Tasks Published in: Proc. of the 6th Int. Symp. on Distributed Autonomous Robotic Systems DARS-02, 289-298 Year: 2002 Laboratories:	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8784147500991821, "perplexity": 16342.889993809846}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-13/segments/1521257647530.92/warc/CC-MAIN-20180320185657-20180320205657-00699.warc.gz"}
https://projects.coin-or.org/CppAD/changeset/3346	# Changeset 3346 Ignore: Timestamp: Sep 20, 2014 9:24:28 AM (6 years ago) Message: Fix doxygen documentation for cache arrays. Location: branches/cache/cppad/local Files: 2 edited Unmodified Added Removed • ## branches/cache/cppad/local/forward1sweep.hpp r3344 \b Output: For i = n+1 , ... , num_var-1, and k = 0 , ... , p-1, k = p , ... , q, taylor[ Ji + k] is the k-th order Taylor coefficient corresponding to the i-th variable. \n \n \b Cache: For i = num_var, ... , num_var + play->num_cache_rec() - 1, and k = 0 , ... , q, taylor[ Ji + k] is a temporary (use for cache storage). \return • ## branches/cache/cppad/local/forward2sweep.hpp r3345 the i-th variable and all directions. For i = 1 , ... , num_var-1, For k = 1 , ... , q-1, for k = 1 , ... , q-1, ell = 0 , ... , r-1, taylor[ (J-1)ri + i + (k-1)r + ell + 1 ] is the q-th order Taylor coefficient corresponding to the i-th variable and ell-th direction. \n \n \b Cache: For i = num_var, ... , num_var + play->num_cache_rec() - 1, k = 1 , ... , q, ell = 0 , ... , r-1, taylor[ (J-1)ri + i + (k-1)r + ell + 1 ] and taylor[ (J-1)ri + i ] are temporary storage (used for cache). \param cskip_op Note: See TracChangeset for help on using the changeset viewer.	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.929990291595459, "perplexity": 5043.437251639675}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-16/segments/1585370518622.65/warc/CC-MAIN-20200403190006-20200403220006-00150.warc.gz"}
https://api-project-1022638073839.appspot.com/questions/how-do-you-integrate-int-x-5-x-3-x-7-x-5-using-partial-fractions	Calculus Topics # How do you integrate int (x+5)/((x+3)(x-7)(x-5)) using partial fractions? int (x+5)/((x+3)(x-7)(x-5) $\mathrm{dx}$ $= \frac{1}{40} \cdot \ln \left(x + 3\right) + \frac{3}{5} \cdot \ln \left(x - 7\right) - \frac{5}{8} \cdot \ln \left(x - 5\right) + K$ for a definite integral, a constant K must be added. #### Explanation: from the given $\int \frac{x + 5}{\left(x + 3\right) \left(x - 7\right) \left(x - 5\right)}$ $\mathrm{dx}$ = $\int \frac{A}{x + 3}$$\mathrm{dx}$ + $\frac{B}{x - 7}$$\mathrm{dx}$ + $\frac{C}{x - 5}$$\mathrm{dx}$ our equation becomes (x+5)/((x+3)(x-7)(x-5)= $\frac{A}{x + 3} + \frac{B}{x - 7} + \frac{C}{x - 5}$ it follows; (x+5)/((x+3)(x-7)(x-5)= $\frac{A \left(x - 7\right) \left(x - 5\right) + B \left(x + 3\right) \left(x - 5\right) + C \left(x + 3\right) \left(x - 5\right)}{\left(x + 3\right) \left(x - 5\right) \left(x - 7\right)}$ by using only the numerators; x+5=A(x^2-12x+35)+B(x^2-2x-15)+C(x^2-4x-21) collecting the like terms $x + 5 = \left(A + B + C\right) {x}^{2} + \left(- 12 A - 2 B - 4 C\right) x + \left(35 A - 15 B - 21 C\right)$ because the left side of the equation means $0 \cdot {x}^{2} + 1 \cdot x + 5$ and the right side means $\left(A + B + C\right) {x}^{2} + \left(- 12 A - 2 B - 4 C\right) x + \left(35 A - 15 B - 21 C\right)$ the equations are now formed; $A + B + C = 0$ first equation $- 12 A - 2 B - 4 C = 1$ second equation $35 A - 15 B - 21 C = 5$ third equation using your skills in solving 3 equations with 3 unknowns A, B, C the values are $A = \frac{1}{40}$, $B = \frac{3}{5}$, and $C = - \frac{5}{8}$ Now, go back to the first line of the explanation to do the integration procedures. $\int \frac{A}{x + 3}$$\mathrm{dx}$ + $\frac{B}{x - 7}$$\mathrm{dx}$ + $\frac{C}{x - 5}$$\mathrm{dx}$ $= \int \frac{\frac{1}{40}}{x + 3}$$\mathrm{dx}$ + $\int \frac{\frac{3}{5}}{x - 7}$$\mathrm{dx}$ + $\int \frac{- \frac{5}{8}}{x - 5}$$\mathrm{dx}$ int (x+5)/((x+3)(x-7)(x-5) $\mathrm{dx}$ $= \frac{1}{40} \cdot \ln \left(x + 3\right) + \frac{3}{5} \cdot \ln \left(x - 7\right) - \frac{5}{8} \cdot \ln \left(x - 5\right) + K$	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 40, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9983240365982056, "perplexity": 2813.8384603081076}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-43/segments/1634323585199.76/warc/CC-MAIN-20211018062819-20211018092819-00349.warc.gz"}
https://mathoverflow.net/questions/194775/groupoid-cardinality-of-dm-stack-and-point-counting-on-coarse-moduli-spaces	# Groupoid cardinality of DM stack and point counting on coarse moduli spaces Let $X$ be a finite type DM stack over a finite field $k$ with a coarse moduli space $X_c$. (We only assume $X_c$ is an algebraic space and $X$ might have infinite inertia stack.) Under which conditions is $\# X(k) = \# X_c(k)$? Here we take the groupoid cardinality/stacky sum/mass formula to define $\#X(k)$: $$\# X(k) := \sum_{x\in X(k)} \frac{1}{\# Aut(x)}.$$ I think this equality holds if $X$ is a separated finite type DM stack whose coarse moduli space is a scheme (and not just an algebraic space). Does it hold more generally, ie, only assuming the existence of $X_c$ and not any other properties? • How do you prove it in the case you mention? – Mattia Talpo Feb 5 '15 at 7:41	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9321514964103699, "perplexity": 299.92745908408193}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-18/segments/1555578721468.57/warc/CC-MAIN-20190425134058-20190425160058-00489.warc.gz"}
https://www.hepdata.net/record/78802	• Browse all Charged-particle multiplicity distributions over a wide pseudorapidity range in proton-proton collisions at $\mathbf{\sqrt{s}=}$ 0.9, 7 and 8 TeV The collaboration No Journal Information, 2017 Abstract (data abstract) Measurements of charged particle multiplicities in pp collisions at centre-of-mass energies from 900 to 8000 GeV in the pseudorapidity range -3.4 to 5.0. Results are given for three normalizations: INEL (the sum of all inelastic interactions), NSD (non-single diffractive, i.e. non-diffractive and double processes only) and INEL>0 class of events, which requires at least one charged particle in the final state in the pseudorapidiy range -1 to 1. • Table 1 Data from Fig. 3 (top left) 10.17182/hepdata.78802.v1/t1 Multiplicity distribution in the pseudorapidity region -2.0 to 2.0 for NSD collisions at a centre-of-mass energy of 900 GeV. • Table 2 Data from Fig. 3 (top left) 10.17182/hepdata.78802.v1/t2 Multiplicity distribution in the pseudorapidity region -2.4 to 2.4 for NSD collisions at a centre-of-mass energy of 900 GeV. • Table 3 Data from Fig. 3 (top left) 10.17182/hepdata.78802.v1/t3 Multiplicity distribution in the pseudorapidity region -3.0 to 3.0 for NSD collisions at a centre-of-mass energy of 900 GeV. • Table 4 Data from Fig. 3 (top left) 10.17182/hepdata.78802.v1/t4 Multiplicity distribution in the pseudorapidity region -3.4 to 3.4 for NSD collisions at a centre-of-mass energy of 900 GeV. • Table 5 Data from Fig. 3 (top left) 10.17182/hepdata.78802.v1/t5 Multiplicity distribution in the pseudorapidity region -3.4 to 5.0 for NSD collisions at a centre-of-mass energy of 900 GeV. • Table 6 Data from Fig. 4 (top left) 10.17182/hepdata.78802.v1/t6 Multiplicity distribution in the pseudorapidity region -2.0 to 2.0 for NSD collisions at a centre-of-mass energy of 7000 GeV. • Table 7 Data from Fig. 4 (top left) 10.17182/hepdata.78802.v1/t7 Multiplicity distribution in the pseudorapidity region -2.4 to 2.4 for NSD collisions at a centre-of-mass energy of 7000 GeV. • Table 8 Data from Fig. 4 (top left) 10.17182/hepdata.78802.v1/t8 Multiplicity distribution in the pseudorapidity region -3.0 to 3.0 for NSD collisions at a centre-of-mass energy of 7000 GeV. • Table 9 Data from Fig. 4 (top left) 10.17182/hepdata.78802.v1/t9 Multiplicity distribution in the pseudorapidity region -3.4 to 3.4 for NSD collisions at a centre-of-mass energy of 7000 GeV. • Table 10 Data from Fig. 4 (top left) 10.17182/hepdata.78802.v1/t10 Multiplicity distribution in the pseudorapidity region -3.4 to 5.0 for NSD collisions at a centre-of-mass energy of 7000 GeV. • Table 11 Data from Fig. 5 (top left) 10.17182/hepdata.78802.v1/t11 Multiplicity distribution in the pseudorapidity region -2.0 to 2.0 for NSD collisions at a centre-of-mass energy of 8000 GeV. • Table 12 Data from Fig. 5 (top left) 10.17182/hepdata.78802.v1/t12 Multiplicity distribution in the pseudorapidity region -2.4 to 2.4 for NSD collisions at a centre-of-mass energy of 8000 GeV. • Table 13 Data from Fig. 5 (top left) 10.17182/hepdata.78802.v1/t13 Multiplicity distribution in the pseudorapidity region -3.0 to 3.0 for NSD collisions at a centre-of-mass energy of 8000 GeV. • Table 14 Data from Fig. 5 (top left) 10.17182/hepdata.78802.v1/t14 Multiplicity distribution in the pseudorapidity region -3.4 to 3.4 for NSD collisions at a centre-of-mass energy of 8000 GeV. • Table 15 Data from Fig. 5 (top left) 10.17182/hepdata.78802.v1/t15 Multiplicity distribution in the pseudorapidity region -3.4 to 5.0 for NSD collisions at a centre-of-mass energy of 8000 GeV. • Table 16 Data from Fig. 3 (top right) 10.17182/hepdata.78802.v1/t16 Multiplicity distribution in the pseudorapidity region -2.0 to 2.0 for INEL collisions at a centre-of-mass energy of 900 GeV. • Table 17 Data from Fig. 3 (top right) 10.17182/hepdata.78802.v1/t17 Multiplicity distribution in the pseudorapidity region -2.4 to 2.4 for INEL collisions at a centre-of-mass energy of 900 GeV. • Table 18 Data from Fig. 3 (top right) 10.17182/hepdata.78802.v1/t18 Multiplicity distribution in the pseudorapidity region -3.0 to 3.0 for INEL collisions at a centre-of-mass energy of 900 GeV. • Table 19 Data from Fig. 3 (top right) 10.17182/hepdata.78802.v1/t19 Multiplicity distribution in the pseudorapidity region -3.4 to 3.4 for INEL collisions at a centre-of-mass energy of 900 GeV. • Table 20 Data from Fig. 3 (top right) 10.17182/hepdata.78802.v1/t20 Multiplicity distribution in the pseudorapidity region -3.4 to 5.0 for INEL collisions at a centre-of-mass energy of 900 GeV. • Table 21 Data from Fig. 4 (top right) 10.17182/hepdata.78802.v1/t21 Multiplicity distribution in the pseudorapidity region -2.0 to 2.0 for INEL collisions at a centre-of-mass energy of 7000 GeV. • Table 22 Data from Fig. 4 (top right) 10.17182/hepdata.78802.v1/t22 Multiplicity distribution in the pseudorapidity region -2.4 to 2.4 for INEL collisions at a centre-of-mass energy of 7000 GeV. • Table 23 Data from Fig. 4 (top right) 10.17182/hepdata.78802.v1/t23 Multiplicity distribution in the pseudorapidity region -3.0 to 3.0 for INEL collisions at a centre-of-mass energy of 7000 GeV. • Table 24 Data from Fig. 4 (top right) 10.17182/hepdata.78802.v1/t24 Multiplicity distribution in the pseudorapidity region -3.4 to 3.4 for INEL collisions at a centre-of-mass energy of 7000 GeV. • Table 25 Data from Fig. 4 (top right) 10.17182/hepdata.78802.v1/t25 Multiplicity distribution in the pseudorapidity region -3.4 to 5.0 for INEL collisions at a centre-of-mass energy of 7000 GeV. • Table 26 Data from Fig. 5 (top right) 10.17182/hepdata.78802.v1/t26 Multiplicity distribution in the pseudorapidity region -2.0 to 2.0 for INEL collisions at a centre-of-mass energy of 8000 GeV. • Table 27 Data from Fig. 5 (top right) 10.17182/hepdata.78802.v1/t27 Multiplicity distribution in the pseudorapidity region -2.4 to 2.4 for INEL collisions at a centre-of-mass energy of 8000 GeV. • Table 28 Data from Fig. 5 (top right) 10.17182/hepdata.78802.v1/t28 Multiplicity distribution in the pseudorapidity region -3.0 to 3.0 for INEL collisions at a centre-of-mass energy of 8000 GeV. • Table 29 Data from Fig. 5 (top right) 10.17182/hepdata.78802.v1/t29 Multiplicity distribution in the pseudorapidity region -3.4 to 3.4 for INEL collisions at a centre-of-mass energy of 8000 GeV. • Table 30 Data from Fig. 5 (top right) 10.17182/hepdata.78802.v1/t30 Multiplicity distribution in the pseudorapidity region -3.4 to 5.0 for INEL collisions at a centre-of-mass energy of 8000 GeV. • Table 31 Data from Fig. 3 (bottom) 10.17182/hepdata.78802.v1/t31 Multiplicity distribution in the pseudorapidity region -2.0 to 2.0 for INEL>0 collisions at a centre-of-mass energy of 900 GeV. • Table 32 Data from Fig. 3 (bottom) 10.17182/hepdata.78802.v1/t32 Multiplicity distribution in the pseudorapidity region -2.4 to 2.4 for INEL>0 collisions at a centre-of-mass energy of 900 GeV. • Table 33 Data from Fig. 3 (bottom) 10.17182/hepdata.78802.v1/t33 Multiplicity distribution in the pseudorapidity region -3.0 to 3.0 for INEL>0 collisions at a centre-of-mass energy of 900 GeV. • Table 34 Data from Fig. 3 (bottom) 10.17182/hepdata.78802.v1/t34 Multiplicity distribution in the pseudorapidity region -3.4 to 3.4 for INEL>0 collisions at a centre-of-mass energy of 900 GeV. • Table 35 Data from Fig. 3 (bottom) 10.17182/hepdata.78802.v1/t35 Multiplicity distribution in the pseudorapidity region -3.4 to 5.0 for INEL>0 collisions at a centre-of-mass energy of 900 GeV. • Table 36 Data from Fig. 4 (bottom) 10.17182/hepdata.78802.v1/t36 Multiplicity distribution in the pseudorapidity region -2.0 to 2.0 for INEL>0 collisions at a centre-of-mass energy of 7000 GeV. • Table 37 Data from Fig. 4 (bottom) 10.17182/hepdata.78802.v1/t37 Multiplicity distribution in the pseudorapidity region -2.4 to 2.4 for INEL>0 collisions at a centre-of-mass energy of 7000 GeV. • Table 38 Data from Fig. 4 (bottom) 10.17182/hepdata.78802.v1/t38 Multiplicity distribution in the pseudorapidity region -3.0 to 3.0 for INEL>0 collisions at a centre-of-mass energy of 7000 GeV. • Table 39 Data from Fig. 4 (bottom) 10.17182/hepdata.78802.v1/t39 Multiplicity distribution in the pseudorapidity region -3.4 to 3.4 for INEL>0 collisions at a centre-of-mass energy of 7000 GeV. • Table 40 Data from Fig. 4 (bottom) 10.17182/hepdata.78802.v1/t40 Multiplicity distribution in the pseudorapidity region -3.4 to 5.0 for INEL>0 collisions at a centre-of-mass energy of 7000 GeV. • Table 41 Data from Fig. 5 (bottom) 10.17182/hepdata.78802.v1/t41 Multiplicity distribution in the pseudorapidity region -2.0 to 2.0 for INEL>0 collisions at a centre-of-mass energy of 8000 GeV. • Table 42 Data from Fig. 5 (bottom) 10.17182/hepdata.78802.v1/t42 Multiplicity distribution in the pseudorapidity region -2.4 to 2.4 for INEL>0 collisions at a centre-of-mass energy of 8000 GeV. • Table 43 Data from Fig. 5 (bottom) 10.17182/hepdata.78802.v1/t43 Multiplicity distribution in the pseudorapidity region -3.0 to 3.0 for INEL>0 collisions at a centre-of-mass energy of 8000 GeV. • Table 44 Data from Fig. 5 (bottom) 10.17182/hepdata.78802.v1/t44 Multiplicity distribution in the pseudorapidity region -3.4 to 3.4 for INEL>0 collisions at a centre-of-mass energy of 8000 GeV. • Table 45 Data from Fig. 5 (bottom) 10.17182/hepdata.78802.v1/t45 Multiplicity distribution in the pseudorapidity region -3.4 to 5.0 for INEL>0 collisions at a centre-of-mass energy of 8000 GeV. • Table 46 Data from Table 4 10.17182/hepdata.78802.v1/t46 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.0 to 2.0 in NSD collisions at center-of-mass energy... • Table 47 Data from Table 4 10.17182/hepdata.78802.v1/t47 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.4 to 2.4 in NSD collisions at center-of-mass energy... • Table 48 Data from Table 4 10.17182/hepdata.78802.v1/t48 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.0 to 3.0 in NSD collisions at center-of-mass energy... • Table 49 Data from Table 4 10.17182/hepdata.78802.v1/t49 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 3.4 in NSD collisions at center-of-mass energy... • Table 50 Data from Table 4 10.17182/hepdata.78802.v1/t50 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 5.0 in NSD collisions at center-of-mass energy... • Table 51 Data from Table 4 10.17182/hepdata.78802.v1/t51 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.0 to 2.0 in NSD collisions at center-of-mass energy... • Table 52 Data from Table 4 10.17182/hepdata.78802.v1/t52 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.4 to 2.4 in NSD collisions at center-of-mass energy... • Table 53 Data from Table 4 10.17182/hepdata.78802.v1/t53 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.0 to 3.0 in NSD collisions at center-of-mass energy... • Table 54 Data from Table 4 10.17182/hepdata.78802.v1/t54 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 3.4 in NSD collisions at center-of-mass energy... • Table 55 Data from Table 4 10.17182/hepdata.78802.v1/t55 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 5.0 in NSD collisions at center-of-mass energy... • Table 56 Data from Table 4 10.17182/hepdata.78802.v1/t56 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.0 to 2.0 in NSD collisions at center-of-mass energy... • Table 57 Data from Table 4 10.17182/hepdata.78802.v1/t57 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.4 to 2.4 in NSD collisions at center-of-mass energy... • Table 58 Data from Table 4 10.17182/hepdata.78802.v1/t58 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.0 to 3.0 in NSD collisions at center-of-mass energy... • Table 59 Data from Table 4 10.17182/hepdata.78802.v1/t59 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 3.4 in NSD collisions at center-of-mass energy... • Table 60 Data from Table 4 10.17182/hepdata.78802.v1/t60 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 5.0 in NSD collisions at center-of-mass energy... • Table 61 Data from Table 5 10.17182/hepdata.78802.v1/t61 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.0 to 2.0 in INEL collisions at center-of-mass energy... • Table 62 Data from Table 5 10.17182/hepdata.78802.v1/t62 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.4 to 2.4 in INEL collisions at center-of-mass energy... • Table 63 Data from Table 5 10.17182/hepdata.78802.v1/t63 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.0 to 3.0 in INEL collisions at center-of-mass energy... • Table 64 Data from Table 5 10.17182/hepdata.78802.v1/t64 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 3.4 in INEL collisions at center-of-mass energy... • Table 65 Data from Table 5 10.17182/hepdata.78802.v1/t65 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 5.0 in INEL collisions at center-of-mass energy... • Table 66 Data from Table 5 10.17182/hepdata.78802.v1/t66 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.0 to 2.0 in INEL collisions at center-of-mass energy... • Table 67 Data from Table 5 10.17182/hepdata.78802.v1/t67 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.4 to 2.4 in INEL collisions at center-of-mass energy... • Table 68 Data from Table 5 10.17182/hepdata.78802.v1/t68 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.0 to 3.0 in INEL collisions at center-of-mass energy... • Table 69 Data from Table 5 10.17182/hepdata.78802.v1/t69 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 3.4 in INEL collisions at center-of-mass energy... • Table 70 Data from Table 5 10.17182/hepdata.78802.v1/t70 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 5.0 in INEL collisions at center-of-mass energy... • Table 71 Data from Table 5 10.17182/hepdata.78802.v1/t71 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.0 to 2.0 in INEL collisions at center-of-mass energy... • Table 72 Data from Table 5 10.17182/hepdata.78802.v1/t72 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.4 to 2.4 in INEL collisions at center-of-mass energy... • Table 73 Data from Table 5 10.17182/hepdata.78802.v1/t73 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.0 to 3.0 in INEL collisions at center-of-mass energy... • Table 74 Data from Table 5 10.17182/hepdata.78802.v1/t74 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 3.4 in INEL collisions at center-of-mass energy... • Table 75 Data from Table 5 10.17182/hepdata.78802.v1/t75 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 5.0 in INEL collisions at center-of-mass energy... • Table 76 Data from Table 6 10.17182/hepdata.78802.v1/t76 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.0 to 2.0 in INEL>0 collisions at center-of-mass energy... • Table 77 Data from Table 6 10.17182/hepdata.78802.v1/t77 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.4 to 2.4 in INEL>0 collisions at center-of-mass energy... • Table 78 Data from Table 6 10.17182/hepdata.78802.v1/t78 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.0 to 3.0 in INEL>0 collisions at center-of-mass energy... • Table 79 Data from Table 6 10.17182/hepdata.78802.v1/t79 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 3.4 in INEL>0 collisions at center-of-mass energy... • Table 80 Data from Table 6 10.17182/hepdata.78802.v1/t80 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 5.0 in INEL>0 collisions at center-of-mass energy... • Table 81 Data from Table 6 10.17182/hepdata.78802.v1/t81 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.0 to 2.0 in INEL>0 collisions at center-of-mass energy... • Table 82 Data from Table 6 10.17182/hepdata.78802.v1/t82 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.4 to 2.4 in INEL>0 collisions at center-of-mass energy... • Table 83 Data from Table 6 10.17182/hepdata.78802.v1/t83 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.0 to 3.0 in INEL>0 collisions at center-of-mass energy... • Table 84 Data from Table 6 10.17182/hepdata.78802.v1/t84 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 3.4 in INEL>0 collisions at center-of-mass energy... • Table 85 Data from Table 6 10.17182/hepdata.78802.v1/t85 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 5.0 in INEL>0 collisions at center-of-mass energy... • Table 86 Data from Table 6 10.17182/hepdata.78802.v1/t86 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.0 to 2.0 in INEL>0 collisions at center-of-mass energy... • Table 87 Data from Table 6 10.17182/hepdata.78802.v1/t87 Set of fit parameters for the multiplicity distribution in pseudorapidity range -2.4 to 2.4 in INEL>0 collisions at center-of-mass energy... • Table 88 Data from Table 6 10.17182/hepdata.78802.v1/t88 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.0 to 3.0 in INEL>0 collisions at center-of-mass energy... • Table 89 Data from Table 6 10.17182/hepdata.78802.v1/t89 Set of fit parameters for the multiplicity distribution in pseudorapidity range -3.4 to 3.4 in INEL>0 collisions at center-of-mass energy... • Table 90 Data from Table 6 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http://mathematica.stackexchange.com/questions/19403/plot-breaks-behavior-of-custom-data-handling-function-recursion?answertab=oldest	# Plot[] breaks behavior of custom data handling function - Recursion I am working on a utility to analyze a set of data. I want to process the data with a sliding window, in such a way that there is an output associated with each sample of data. To start, I have a list of data: MyData I've defined the following utility function to pull 10 consecutive samples of data from MyData starting at an arbitrary location within MyData. EvalWin[x_] := Take[MyData, {x, x + 9}]; This works. Now lets say I have a processing function that sums the 10 samples. ProcData[x_] := Total[EvalWin[x]]; This also works. The problem comes if I attempt to use ProcData[] as an argument to a built in Mathematica function such as Plot. For example if I attempt to plot ProcData[] for a set of 100 samples... Plot[ProcData[x], {x, 10, 110}] The Plot function blows up due to recursion. Are there ways to control how built in functions handle data to avoid recursive blow up, or is there a more Mathematica friendly way to accomplish this kind of data manipulation? - Your problem isn't recursion, it's the fact that array indices have to be positive integers and Plot assumes a continuous variable. – Jens Feb 11 '13 at 4:56 By the way, in case you're really interested in something like what your example does, maybe take a look at MovingAverage – Jens Feb 11 '13 at 5:10 Use DiscretePlot[] instead for integer-valued functions: ProcData[x_Integer] := Sum[MyData[[k]], {k, x, x + 9}] This (+1), or ListPlot seem to be the most appropriate solutions. Or one could stick with Plot and replace ProcData[x] with ProcData[Floor[x]]. – Jens Feb 11 '13 at 4:54	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.22350792586803436, "perplexity": 1496.052108080902}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-35/segments/1440644064420.15/warc/CC-MAIN-20150827025424-00241-ip-10-171-96-226.ec2.internal.warc.gz"}
https://www.physicsforums.com/threads/math-log-proof.21341/	# Math log proof 1. Apr 18, 2004 ### gnome Would someone please show me why $${ a^{log_cb} = b^{log_ca}$$ for all a, b and c. 2. Apr 18, 2004 ### deltabourne I don't know if this is really a proof.. but just take the log of both sides: $${ a^{log_cb} = b^{log_ca}$$ $$log_c { a^{log_cb} = log_c b^{log_ca}$$ $$({log_cb})({log_ca}) = ({log_ca})({log_cb})$$ using the property that: $${log_ca^r} = r{log_ca}$$ 3. Apr 18, 2004 ### matt grime it is a proof. perhaps to make it appear more rigorous, you could write $$a^{log_cb}=c^{log_c(a^{log_cb})}$$ and similarly for the rhs, and say that the only way for c^xto be equal to c^y is if x=y. 4. Apr 18, 2004 ### gnome Got it! Thanks, folks. Similar Discussions: Math log proof	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9120255708694458, "perplexity": 3794.265107183814}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-17/segments/1492917121453.27/warc/CC-MAIN-20170423031201-00638-ip-10-145-167-34.ec2.internal.warc.gz"}
https://rojefferson.blog/2019/10/27/interior-operators-in-ads-cft/	In a previous post, I mentioned that the firewall paradox could be phrased as a question about the existence of interior operators that satisfy the correct thermal correlation functions, namely $\displaystyle \langle\Psi\|\mathcal{O}(t,\mathbf{x})\tilde{\mathcal{O}}(t',\mathbf{x}')\|\Psi\rangle =Z^{-1}\mathrm{tr}\left[e^{-\beta H}\mathcal{O}(t,\mathbf{x})\mathcal{O}(t'+i\beta/2,\mathbf{x}')\right]~, \ \ \ \ \ (1)$ where ${\tilde{\mathcal{O}}}$ and ${\mathcal{O}}$ operators inside and outside the black hole, respectively; cf. eqn. (2) here. In this short post, I’d like to review the basic argument leading up to this statement, following the original works [1,2]. Consider the eternal black hole in AdS as depicted in the following diagram, which I stole from [1]: The blue line connecting the two asymptotic boundaries is the Cauchy slice on which we’ll construct our states, denoted ${\Sigma_I}$ in exterior region ${I}$ and ${\Sigma_{III}}$ in exterior region ${III}$. Note that, modulo possible UV divergences at the origin, either half serves as a complete Cauchy slice if we restrict our inquiries to the associated exterior region. But if we wish to reconstruct states in the interior (henceforth just ${II}$, since we don’t care about ${IV}$), then we need the entire slice. Pictorially, one can see this from the fact that only the left-moving modes from region ${I}$, and the right-moving modes from region ${III}$, cross the horizon into region ${II}$, but we need both left- and right-movers to have a complete mode decomposition. To expand on this, imagine we proceed with the quantization of a free scalar field in region ${I}$. We need to solve the Klein-Gordon equation, $\displaystyle \left(\square-m^2\right)\phi=\frac{1}{\sqrt{-g}}\,\partial_\mu\left( g^{\mu\nu}\sqrt{-g}\,\partial_\nu\phi\right)-m^2\phi=0 \ \ \ \ \ (2)$ on the AdS black brane background, $\displaystyle \mathrm{d} s^2=\frac{1}{z^2}\left[-h(z)\mathrm{d} t^2+\mathrm{d} z^2+\mathrm{d}\mathbf{x}^2\right]~, \quad\quad h(z)\equiv1-\left(\frac{z}{z_0}\right)^d~. \ \ \ \ \ (3)$ where, in Poincaré coordinates, the asymptotic boundary is at ${z\!=\!0}$, and the horizon is at ${z\!=\!z_0}$. We work in ${(d+1)-}$spacetime dimensions, so ${\mathbf{x}}$ is a ${(d\!-\!1)}$-dimensional vector representing the transverse coordinates. Note that we’ve set the AdS radius to 1. Substituting the usual plane-wave ansatz $\displaystyle f_{\omega,\mathbf{k}}(t,\mathbf{x},z)=e^{-i\omega t+i\mathbf{k}\mathbf{x}}\psi_{\omega,\mathbf{k}(z)} \ \ \ \ \ (4)$ into the Klein-Gordon equation results in a second order ordinary differential equation for the radial function ${\psi_{\omega,\mathbf{k}}(z)}$, and hence two linearly independent solutions. As usual, we then impose normalizable boundary conditions at infinity, which leaves us with a single linear combination for each ${(\omega,\mathbf{k})}$. Note that we do not impose boundary conditions at the horizon. Naïvely, one might have thought to impose ingoing boundary conditions there; however, as remarked in [1], this precludes the existence of real ${\omega}$. More intuitively, I think of this as simply the statement that the black hole is evaporating, so we should allow the possibility for outgoing modes as well. (That is, assuming a large black hole in AdS, the black hole is in thermal equilibrium with the surrounding environment, so the outgoing and ingoing fluxes are precisely matched, and it maintains constant size). The expression for ${\psi_{\omega,\mathbf{k}}(z)}$ is not relevant here; see [1] for more details. We thus arrive at the standard expression of the (bulk) field ${\phi}$ in terms of creation and annihilation operators, $\displaystyle \phi_I(t,\mathbf{x},z)=\int_{\omega>0}\frac{\mathrm{d}\omega\mathrm{d}^{d-1}\mathbf{k}}{\sqrt{2\omega}(2\pi)^d}\,\bigg[ a_{\omega,\mathbf{k}}\,f_{\omega,\mathbf{k}}(t,\mathbf{x},z)+\mathrm{h.c.}\bigg]~, \ \ \ \ \ (5)$ where the creation/annihilation operators for the modes may be normalized with respect to the Klein-Gordon norm, so that $\displaystyle [a_{\omega,\mathbf{k}},a^\dagger_{\omega',\mathbf{k}'}]=\delta(\omega-\omega')\delta^{d-1}(\mathbf{k}-\mathbf{k}')~. \ \ \ \ \ (6)$ Of course, a similar expansion holds for region ${III}$: $\displaystyle \phi_{III}(t,\mathbf{x},z)=\int_{\omega>0}\frac{\mathrm{d}\omega\mathrm{d}^{d-1}\mathbf{k}}{\sqrt{2\omega}(2\pi)^d}\,\bigg[\tilde a_{\omega,\mathbf{k}}\,g_{\omega,\mathbf{k}}(t,\mathbf{x},z)+\mathrm{h.c.}\bigg]~, \ \ \ \ \ (7)$ where the mode operators ${\tilde a_{\omega,\mathbf{k}}}$ commute with all ${a_{\omega,\mathbf{k}}}$ by construction. Now, what of the future interior, region ${II}$? Unlike the exterior regions, we no longer have any boundary condition to impose, since every Cauchy slice which crosses this region is bounded on both sides by a future horizon. Consequently, we retain both the linear combinations obtained from the Klein-Gordon equation, and hence have twice as many modes as in either ${I}$ or ${III}$—which makes sense, since the interior receives contributions from both exterior regions. Nonetheless, it may be a bit confusing from the bulk perspective, since any local observer would simply arrive at the usual mode expansion involving only a single set of creation/annihilation operators, and I don’t have an intuition as to how ${a_{\omega,\mathbf{k}}}$ and ${\tilde a_{\omega,\mathbf{k}}}$ relate vis-à-vis their commutation relations in this shared domain. However, the entire framework in which the interior is fed by two exterior regions is only properly formulated in AdS/CFT, in which — it is generally thought — the interior region emerges from the entanglement structure between the two boundaries, so I prefer to uplift this discussion to the CFT before discussing the interior region in detail. This avoids the commutation confusion above — since the operators live in different CFTs — and it was the next step in our analysis anyway. (Incidentally, appendix B of [1] performs the mode decomposition in all three regions explicitly for the case of Rindler space, which provides a nice concrete example in which one can get one’s hands dirty). So, we want to discuss local bulk fields from the perspective of the boundary CFT. From the extrapolate dictionary, we know that local bulk operators become increasingly smeared over the boundary (in both space and time) the farther we move into the bulk. Thus in region ${I}$, we can construct the operator $\displaystyle \phi^I_{\mathrm{CFT}}(t,\mathbf{x},z)=\int_{\omega>0}\frac{\mathrm{d}\omega\mathrm{d}^{d-1}\mathbf{k}}{(2\pi)^d}\,\bigg[\mathcal{O}_{\omega,\mathbf{k}}\,f_{\omega,\mathbf{k}}(t,\mathbf{x},z)+\mathcal{O}^\dagger_{\omega,\mathbf{k}}f^_{\omega,\mathbf{k}}(t,\mathbf{x},z)\bigg]~, \ \ \ \ \ (8)$ which, while a non-local operator in the CFT (constructed from local CFT operators ${\mathcal{O}_{\omega,\mathbf{k}}}$ which act as creation operators of light primary fields), behaves like a local operator in the bulk. Note that from the perspective of the CFT, ${z}$ is an auxiliary coordinate that simply parametrizes how smeared-out this operator is on the boundary. As an aside, the critical difference between (8) and the more familiar HKLL prescription [3-5] is that the former is formulated directly in momentum space, while the latter is defined in position space as $\displaystyle \phi_{\mathrm{CFT}}(t,\mathbf{x},z)=\int\!\mathrm{d} t'\mathrm{d}^{d-1}\mathbf{x}'\,K(t,\mathbf{x},z;t',\mathbf{x}')\mathcal{O}(t',\mathbf{x}')~, \ \ \ \ \ (9)$ where the integration kernel ${K}$ is known as the “smearing function”, and depends on the details of the spacetime. To solve for ${K}$, one performs a mode expansion of the local bulk field ${\phi}$ and identifies the normalizable mode with the local bulk operator ${\mathcal{O}}$ in the boundary limit. One then has to invert this relation to find the bulk mode operator, and then insert this into the original expansion of ${\phi}$. The problem now is that to identify ${K}$, one needs to swap the order of integration between position and momentum space, and the presence of the horizon results in a fatal divergence that obstructs this maneuver. As discussed in more detail in [1] however, working directly in momentum space avoids this technical issue. But the basic relation “smeared boundary operators ${\longleftrightarrow}$ local bulk fields” is the same. Continuing, we have a similar bulk-boundary relation in region ${III}$, in terms of operators ${\tilde{\mathcal{O}}_{\omega,\mathbf{k}}}$ living in the left CFT: $\displaystyle \phi^{III}_{\mathrm{CFT}}(t,\mathbf{x},z)=\int_{\omega>0}\frac{\mathrm{d}\omega\mathrm{d}^{d-1}\mathbf{k}}{(2\pi)^d}\,\bigg[\tilde{\mathcal{O}}_{\omega,\mathbf{k}}\,f_{\omega,\mathbf{k}}(t,\mathbf{x},z)+\tilde{\mathcal{O}}^\dagger_{\omega,\mathbf{k}}f^_{\omega,\mathbf{k}}(t,\mathbf{x},z)\bigg]~. \ \ \ \ \ (10)$ Note that even though I’ve used the same coordinate labels, ${t}$ runs backwards in the left wedge, so that ${\tilde{\mathcal{O}}_{\omega,\mathbf{k}}}$ plays the role of the creation operator here. From the discussion above, the form of the field in the black hole interior is then $\displaystyle \phi^{II}_{\mathrm{CFT}}(t,\mathbf{x},z)=\int_{\omega>0}\frac{\mathrm{d}\omega\mathrm{d}^{d-1}\mathbf{k}}{(2\pi)^d}\,\bigg[\mathcal{O}_{\omega,\mathbf{k}}\,g^{(1)}_{\omega,\mathbf{k}}(t,\mathbf{x},z)+\tilde{\mathcal{O}}_{\omega,\mathbf{k}}g^{(2)}_{\omega,\mathbf{k}}(t,\mathbf{x},z)+\mathrm{h.c}\bigg]~, \ \ \ \ \ (11)$ where ${\mathcal{O}_{\omega,\mathbf{k}}}$ and ${\tilde{\mathcal{O}}_{\omega,\mathbf{k}}}$ are the (creation/annihilation operators for the) boundary modes in the right and left CFTs, respectively. The point is that in order to construct a local field operator behind the horizon, both sets of modes — the left-movers ${\mathcal{O}_{\omega,\mathbf{k}}}$ from ${I}$ and the right-movers ${\tilde{\mathcal{O}}_{\omega,\mathbf{k}}}$ from ${III}$ — are required. In the eternal black hole considered above, the latter originate in the second copy of the CFT. But in the one-sided case, we would seem to have only the left-movers ${\mathcal{O}_{\omega,\mathbf{k}}}$, hence we arrive at the crucial question: for a one-sided black hole — such as that formed from collapse in our universe — what are the interior modes ${\tilde{\mathcal{O}}_{\omega,\mathbf{k}}}$? Equivalently: how can we represent the black hole interior given access to only one copy of the CFT? To answer this question, recall that the thermofield double state, $\displaystyle \|\mathrm{TFD}\rangle=\frac{1}{\sqrt{Z_\beta}}\sum_ie^{-\beta E_i/2}\|E_i\rangle\otimes\|E_i\rangle~, \ \ \ \ \ (12)$ is constructed so that either CFT appears exactly thermal when tracing out the other side, and that this well-approximates the late-time thermodynamics of a large black hole formed from collapse. That is, the exterior region will be in the Hartle-Hawking vacuum (which is to Schwarzschild as Rindler is to Minkowski), with the temperature ${\beta^{-1}}$ of the CFT set by the mass of the black hole. This implies that correlation functions of operators ${\mathcal{O}}$ in the pure state ${\|\mathrm{TFD}\rangle}$ may be computed as thermal expectation values in their (mixed) half of the total Hilbert space, i.e., $\displaystyle \langle\mathrm{TFD}\|\mathcal{O}(t_1,\mathbf{x}_1)\ldots\mathcal{O}(t_n,\mathbf{x}_n)\|\mathrm{TFD}\rangle =Z^{-1}_\beta\mathrm{tr}\left[e^{-\beta H}\mathcal{O}(t_1,\mathbf{x}_1)\ldots\mathcal{O}(t_n,\mathbf{x}_n)\right]~. \ \ \ \ \ (13)$ The same fundamental relation remains true in the case of the one-sided black hole as well: given the Hartle-Hawking state representing the exterior region, we can always obtain a purification such that expectation values in the original, thermal state are equivalent to standard correlators in the “fictitious” pure state, by the same doubling formalism that yielded the TFD. (Of course, the purification of a given mixed state is not unique, but as pointed out in [2] “the correct way to pick it, assuming that expectation values [of the operators] are all the information we have, is to pick the density matrix which maximizes the entropy.” That is, we pick the purification such that the original mixed state is thermal, i.e., ${\rho\simeq Z^{-1}_\beta e^{-\beta H}}$ up to ${1/N^2}$ corrections. The reason this is the “correct” prescription is that it’s the only one which does not impose additional constraints.) Thus (13) can be generally thought of as the statement that operators in an arbitrary pure state have the correct thermal expectation values when restricted to some suitably mixed subsystem (e.g., the black hole exterior dual to a single CFT). Now, what if we wish to compute a correlation function involving operators across the horizon, e.g., ${\langle\mathcal{O}\tilde{\mathcal{O}}\rangle}$? In the two-sided case, we can simply compute this correlator in the pure state ${\|\mathrm{TFD}\rangle}$. But in the one-sided case, we only have access to the thermal state representing the exterior. Thus we’d like to know how to compute the correlator using only the available data in the CFT corresponding to region ${I}$. In order to do this, we re-express all operators ${\tilde{\mathcal{O}}}$ appearing in the correlator with analytically continued operators ${\mathcal{O}}$ via the KMS condition, i.e., we make the replacement $\displaystyle \tilde{\mathcal{O}}(t,\mathbf{x}) \longrightarrow \mathcal{O}(t+i\beta/2,\mathbf{x})~. \ \ \ \ \ (14)$ This is essentially the usual statement that thermal Green functions are periodic in imaginary time; see [1] for details. This relationship allows us to express the desired correlator as $\displaystyle \langle\mathrm{TFD}\|\mathcal{O}(t_1,\mathbf{x}_1)\ldots\tilde{\mathcal{O}}(t_n,\mathbf{x}_n)\|\mathrm{TFD}\rangle =Z^{-1}_\beta\mathrm{tr}\left[e^{-\beta H}\mathcal{O}(t_1,\mathbf{x}_1)\ldots\mathcal{O}_{\omega,\mathbf{k}}(t_n+i\beta/2,\mathbf{x}_n)\right]~, \ \ \ \ \ (15)$ which is precisely eqn. (2) in our earlier post, cf. the two-point function (1) above. Note the lack of tilde’s on the right-hand side: this thermal expectation value can be computed entirely in the right CFT. If the CFT did not admit operators which satisfy the correlation relation (15), it would imply a breakdown of effective field theory across the horizon. Alternatively, observing deviations from the correct thermal correlators would allow us to locally detect the horizon, in contradiction to the equivalence principle. In this sense, this expression may be summarized as the statement that the horizon is smooth. Thus, for the CFT to represent a black hole with no firewall, it must contain a representation of interior operators ${\tilde{\mathcal{O}}}$ with the correct behaviour inside low-point correlators. This last qualifier hints at the state-dependent nature of these so-called “mirror operators”, which I’ve discussed at length elsewhere [6]. References [1] K. Papadodimas and S. Raju, “An Infalling Observer in AdS/CFT,” JHEP 10 (2013) 212,arXiv:1211.6767 [hep-th]. [2] K. Papadodimas and S. Raju, “State-Dependent Bulk-Boundary Maps and Black Hole Complementarity,” Phys. Rev. D89 no. 8, (2014) 086010, arXiv:1310.6335 [hep-th]. [3] A. Hamilton, D. N. Kabat, G. Lifschytz, and D. A. Lowe, “Holographic representation of local bulk operators,” Phys. Rev. D74 (2006) 066009, arXiv:hep-th/0606141 [hep-th]. [4] A. Hamilton, D. N. Kabat, G. Lifschytz, and D. A. Lowe, “Local bulk operators in AdS/CFT: A Boundary view of horizons and locality,” Phys. Rev. D73 (2006) 086003,arXiv:hep-th/0506118 [hep-th]. [5] A. Hamilton, D. N. Kabat, G. Lifschytz, and D. A. Lowe, “Local bulk operators in AdS/CFT: A Holographic description of the black hole interior,” Phys. Rev. D75 (2007) 106001,arXiv:hep-th/0612053 [hep-th]. [Erratum: Phys. Rev.D75,129902(2007)]. [6] R. Jefferson, “Comments on black hole interiors and modular inclusions,” SciPost Phys. 6 no. 4, (2019) 042, arXiv:1811.08900 [hep-th]. This entry was posted in Physics. 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http://languagelog.ldc.upenn.edu/nll/?p=1664	## When peeves collide … the result is a grammatical bar brawl. An excellent example is on display over at Ask MetaFilter, where someone innocently asked So which sentence is proper English grammar: "If you eat like Bob and me, you will be healthy." or "If you eat like Bob and I, you will be healthy." KA-POW: "it's the second one…" WHAAM: "No, it's the first…" BIFF: "The verb 'do' is implied…" DOINK: "'like' … is indisputably a preposition in this case. It can't even function as a conjunction." And so on. There's some sensible and well-informed advice mixed in with the mud and the blood and the beer, including a link to my discussion of a similar question a few weeks ago ("Write like me?", 7/24/2009). But overall, the chaos of contradictory confidence is likely to reinforce the culture's general state of nervous cluelessness about grammar. In this case, an ample supply of the relevant clues can be found in two entries in MWDEU. The first is the entry for between you and I (p. 181-182): And the second is the entry like, as, as if (p. 600-603): Unfortunately, the answer suggested by the MetaFilter free-for-all still stands — no matter what you do with this question, some peevologist is likely to take a poke at you. But maybe this background will help you get out of the place in one piece. 1. ### John Lawler said, August 15, 2009 @ 11:21 am It's amazing how the concept of 'grammar' exists for so many people solely as a means for putting others down. 'Nervous cluelessness' says it all, I fear. I've said for a long time that grammar is the last great societal taboo in American culture; you can get into more trouble talking about grammar (or rather, 'grammar', as you will be interpreted if you actually try to discuss real grammar) than virtually any other subject. 2. ### Q. Pheevr said, August 15, 2009 @ 12:43 pm The whole question can be neatly circumvented by the simple addition of a comma: If you eat, like, Bob and me, you will be, like, a cannibal, you know? [(myl) Nicely done — except that you've added more than one comma. And perhaps it should be I mean, if you eat, like, Bob and me, you will be, like, basically, a cannibal, you know? Why leave any peeve unprodded? ] 3. ### Craig Russell said, August 15, 2009 @ 1:27 pm As I was reading this, a commercial came on the TV in which a spokeswoman said something to the effect of: "If you're like me, you have problems finding a ________ that works." I imagine a prescriptivist would find fault with this, but what would they suggest as a correction? "If you're like I…"? –Hopelessly awkward. "If you're like I am…"? –Nope, that uses 'like' to introduce a clause. "If you're as I…"? –Worse than the first one. "If you're as I am…"? –Actually hard to understand; sounds like a word is missing. So what's the prescriptivist advice? Just be uncertain about it and worry, I guess. 4. ### The Ridger said, August 15, 2009 @ 2:30 pm Obviously, "If you are a person similar to me…" 5. ### AJD said, August 15, 2009 @ 2:31 pm The prescriptivist advice is that "If you're like me" is correct. 6. ### peter said, August 15, 2009 @ 3:54 pm But surely prescriptivists don't ever say "If you're like me . ." or any of its equivalents, since they think themselves superior to other speakers of the language. 7. ### Stephen Jones said, August 15, 2009 @ 4:24 pm Prescriptivists don't think anybody's like them, so the problem doesn't arise. 8. ### Craig Russell said, August 15, 2009 @ 5:33 pm Wait–AJD is right. The consistent prescriptivist would advocate for "If you're like me." I think I was confusing the prescription about like (that it can never be used as a conjunction) with the one against than (that it can only be used as a conjunction.) I imagine that these two precepts can cause a fair amount of grief for people who try to follow "the rules", because somewhat similar situations lead to two different prescriptions: "He's big, like me." (like is a preposition, and requires an object pronoun) versus "He's bigger than I." (than is a conjunction, and requires a subject pronoun to correlate with "he") Of course it all makes perfect sense if if you know Latin, because then you can just remember that "like" is equal to "similis" and takes the dative, but "than" is equal to the conjunction "quam". Because English grammar has to be just like Latin if it's going to be right. 9. ### Craig Russell said, August 15, 2009 @ 5:45 pm Now that I've posted, I realize that 'similis' is an adjective, not a preposition. Has "like" ever functioned as an adjective in English? Is that why older writers would couple it with another preposition? ("like to _______", "like unto ______") Or maybe I just don't know what I'm talking about… 10. ### Jerry Friedman said, August 15, 2009 @ 6:32 pm "Like" is still an adjective in "Like charges repel", and other like constructions. That's not like, "Like, charges repel." By the way, this isn't the first time I've seen someone criticize prescriptivism and in the process prescribe the correct usage of the word "grammar". 11. ### Craig Russell said, August 15, 2009 @ 7:20 pm @Jerry Friedman If you're referring to what I said about Latin, maybe I didn't make it clear that I was trying to be sarcastic–referring to the old prescriptivist notion that the reason for all the grammar rules that don't describe real usage is because English grammar must somehow map onto Latin grammar. Maybe that didn't come through. I have that problem sometimes on the Internet. 12. ### Russinoff said, August 15, 2009 @ 8:13 pm Craig, I think you mean "the reason … is that" rather than "the reason … is because". It's a common blunder. 13. ### Faldone said, August 15, 2009 @ 8:58 pm The prime rule of prescriptivism: If it works in practice, but not in theory, something must be wrong with the practice. 14. ### Jean-Sébastien Girard said, August 15, 2009 @ 9:39 pm @Faldone Also known as the Wikipedia Dilemma: "It only works in practice, never in theory" 15. ### Jerry Friedman said, August 16, 2009 @ 12:46 am Sorry, Craig, I was referring to John Lawler's comments about grammar, 'grammar', and real grammar, which looked prescriptive to me. I should have been clearer. However, I'm willing to argue with you about Latin. I've read some prescriptivists and seldom seen an argument based on an analogy with Latin. I guess one could make a case that they're not admitting their real reasons. (While I'm on the subject, and speaking of Wikipedia, I'd be grateful for any citation before 1941 of someone condemning split infinitives because they're not like Latin or other languages. I'd add it to the Wikip article. No need for citations of people blaming the split-infinitive prohibition on prescriptivists who want English to be like Latin–I've got plenty of those.) 16. ### Stephen Nicholson said, August 16, 2009 @ 2:56 am Well, the MWDEU speculates on page 868 that "the objection to the split infinitive has never had a rational basis. The original cause for complaint was probably awareness of the relatively sudden marked increase in use of the construction, perhaps combined with the knowledge that in those more elegant languages, Latin and Greek, the infinitive is never split–because it is a single word distinguished by its ending rather than by an introductory particle." I could have sworn that I read somewhere that one of the explicit arguments given in the 19th century for disapproving splitting infinitives was that it was impossible to split them in Latin. 17. ### Ben Hemmens said, August 16, 2009 @ 4:02 am Does it have to be a peeve? I don't really care in a fundamental way which one it is. If one sounds wrong to me, I presume it's because I'm not used to hearing that one in that way. Which probably says something about the parts of the English-speaking world that I've been at home in, in my case Ireland and Scotland. But spontaneously, I'd have said this one is wrong: "Well, President Bush graciously invited Michelle and I to meet with him and First Lady Laura Bush." It's in here, 3rd question: http://en.wikisource.org/wiki/Barack_Obama%27s_president-elect_press_conference_-_7_November_2008 I have the feeling that President Obama tends to do that fairly often, and I wonder what's going on. Do they talk like that in Honolulu, or in Harvard? Or does he semi-consciously feel that "and I" sounds more dignified? 18. ### Ben Hemmens said, August 16, 2009 @ 4:14 am "If you're like me, you have problems finding a ________ that works." I'd say, spot the extinct preposition between "like" and "me" which makes the "me" right. Like "unto". This like has a kind of dative-like movement in it. 19. ### language hat said, August 16, 2009 @ 10:53 am But spontaneously, I'd have said this one is wrong: "Well, President Bush graciously invited Michelle and I to meet with him and First Lady Laura Bush." Many people brought up on traditional "grammar" (it is not prescriptivist to say that use of the word is so misleading as to be useless) think that phrasinig is wrong, but it is extremely common and is probably now Standard Conversational American (I don't know what the situation is like in the U.K. or elsewhere). "X and I" is treated as a fixed phrase, and arguments of the type "but you wouldn't say 'he invited I'" are irrelevant — different structures are treated differently. 20. ### Mark F. said, August 16, 2009 @ 12:15 pm On the face of it, it's actually pretty implausible that 17th or 18th century grammarians would declare a construction poor English because it would have been wrong in Latin. They knew Latin, and hence they really knew how different English grammar was. I realize they must have looked to Latin for the grammatical categories they worked with, and recognized parallels where they existed. But, given all the differences in inflectedness and characteristic word order, it's really hard to imagine why they would use Latin as a model for adverb (and, say, preposition) placement and nothing else. If they were really reasoning from Latin grammar, it would have made more sense for them just to abolish the "to" entirely. 21. ### Jerry Friedman said, August 16, 2009 @ 1:11 pm @Mark F.: I agree with you in general. I'd also be very interested in any prohibition of split infinitives from the 18th century, or any time before 1834. @language hat: I can see that when talking with your fellow linguists, you want to distinguish between between the meaning of "grammar" in linguistics and a meaning that's commonly used by others. I think it's prescriptivist to say that only one meaning is real (as John Lawler did). Using quotation marks for the other meaning looks to me a lot like saying that meaning is wrong. For some people, "X and I" is a fixed phrase only when it's not the subject of a sentence. Here are two sentences from an interview with the singer Uncle Kracker: "Me and him work so well together." "I said this before, but it’s the best analogy I have for he and I is that I don’t talk very much when it comes to just general – usually I’m pretty quiet – and he never shuts the fuck up." 22. ### Stephen Nicholson said, August 16, 2009 @ 2:38 pm "X and I" is treated as a fixed phrase, and arguments of the type "but you wouldn't say 'he invited I'" are irrelevant — different structures are treated differently. You know, I think you've given me a clue to one of the burning questions I have about the way Americans speak. I'll say or hear: I went to the store. or Susie and I went to the store., but it would sound wrong to me to hear I and Susie went to the store. If X and I is a fixed phrase, but I and X isn't, that would suggest to me that it's uncommon (at least in the U.S.) to hear I and X. One of the things I do hear is Me and Z at the beginning of a sentence despite it being near or at the top of many peoples' list of pet peeves. I still find that very odd. 23. ### Russinoff said, August 16, 2009 @ 3:10 pm I too can appreciate Language Hat's complaint that "use of the word is so misleading as to be useless", but what is it that makes his concern for grammar' more legitimate than mine for, say, infer' or decimate' or multiple'? It's a sincere question, asked in hope of gaining a better understanding of y'all's point of view. 24. ### Mark F said, August 16, 2009 @ 4:51 pm Russinoff — Well, for my part I disagree with language hat's claim about use of the word "grammar." I think it really is a grammatical question whether "If you eat like Bob and me…" is correct. There is a distinction between grammar and usage that I think I make, and a lot of people don't, but failure to make that distinction isn't enough to sap the word of its meaning. Language Hat is right that lots of Americans treat "X and I" as a fixed phrase, it having replaced the fixed phrase "me and X" that they were nagged out of as kids. But lots of Americans, I think, have the same intuition you do. I do, anyway. 25. ### BenHemmens said, August 16, 2009 @ 5:45 pm Language Hat: "…it is extremely common and is probably now Standard Conversational American…" What's the opposite of a Chinese person learning English at the nth remove from native speakers? It's a native speaker like me, oh, 15 years or so out of the English-speaking world and starting to feel he's losing touch. Given, in addition, that our household language is developing in the direction of a creole, I sometimes wonder if I'll still be able to translate into English in, say 20 years. It's interesting that you mention the "me" version being drummed out of kids, that's roughly what what I remember from school, too: at least all the correction was in the direction of less "me" and more "I" (school in the 70s and 80s in Ireland). Maybe not just Obama, but large swathes of our generation are hypercorrecting. Does anyone study "peeves of English teachers that go mainstream"? Though I don't really have the impression that this particular quirk is gaining ground in Those Islands. 26. ### BenHemmens said, August 16, 2009 @ 5:56 pm "They knew Latin, and hence they really knew how different English grammar was." Ah, but datives exist in other languages than (modern) English, too. For example, in German we joke "Der Dativ ist dem Genetiv sein Tod", which if anything indicates that the dative is in rude good health. It certainly is in vernacular Austrian German, in which exactly that construction (for possession) is dominant. I wonder when and how the dative died out (or atrophied into whatever hidden vestiges still lurk, like whales' hind legs) in English? Not being a linguist, but a mere biochemist. 27. ### Dan S said, August 18, 2009 @ 9:30 am 'Hat and Ben Hemmer: I would think that "X and I" as object arises from nervous-clueless hypercorrection (which lawyers, like POTUS, tend towards) driven by the prescription against the otherwise-correct "It is me", You hear "invited X and I" but not "invited I", I'll suggest, only because the latter is more-obviously wrong, exposing the hypercorrection. If I'm right about this, then to cover the excellent Kracker observation from Jerry F we need a special case for "me and X" as subject, which overrides whatever rule prevents "I and X {VP}". 28. ### Ben Hemmens said, August 18, 2009 @ 11:53 am "I would think that "X and I" as object arises from nervous-clueless hypercorrection (which lawyers, like POTUS, tend towards)" I think it's very touching if some small part of Obama is still trying to talk like it thinks it should, because it's in Harvard now. 29. ### Anak said, August 18, 2009 @ 2:39 pm The MWDEU quote above says that when stressed, it's "c'est moi" in French. And when it is not stressed, what is it–"c'est je"? It also says that the "French system does not work in reverse." What does that mean? As for Obama, one of my pet peeves is how he ALWAYS pronounces "to" as "tah," never rhyming it with "two." I think he should switch registers there, but maybe that's how they talk at Harvard now… 30. ### Edward Vanderpump said, January 25, 2013 @ 5:46 am Watching Real Housewives of Beverly Hills, two years behind in UK. In addition to the usual, they make extensions into new territory eg "A friend of Kim and I's".	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5026082992553711, "perplexity": 3682.3675063636174}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-22/segments/1464051342447.93/warc/CC-MAIN-20160524005542-00129-ip-10-185-217-139.ec2.internal.warc.gz"}
http://www.thecodingforums.com/threads/includes.801230/	Includes Discussion in 'ASP General' started by Jeff, May 9, 2006. 1. JeffGuest I have an asp page. Now I know this is sortof OT, but I am not sure of the I have an include on this asp page <!-- #include file=\forum\includes\consts-inc.asp --> now, it gives me this error: slash or back slash. i can't use .. either, because it gives me this error:The Include file '..\forum\includes\consts-inc.asp' cannot contain '..' to indicate the parent directory. I tried with the slashes going / and \ if i use this: <!-- #include file=forum/includes/consts-inc.asp --> i get this: for some information. i the file that gives the error is in the includes folder, which is in the root web. the forum folder is also in the root web. so i am in folder unthe root, and trying to include a file from another folder under the root. how can i do this?? Jeff Jeff, May 9, 2006 2. Steven BurnGuest http://support.microsoft.com/default.aspx?scid=kb;en-us;332117 -- Regards Steven Burn Ur I.T. Mate Group www.it-mate.co.uk Keeping it FREE! "Jeff" <> wrote in message news:... > I have an asp page. Now I know this is sortof OT, but I am not sure of the > forum to get an answer. > > I have an include on this asp page > > <!-- #include file=\forum\includes\consts-inc.asp --> > > now, it gives me this error: > slash or back slash. > > i can't use .. either, because it gives me this error:The Include file > '..\forum\includes\consts-inc.asp' cannot contain '..' to indicate the > parent directory. > > I tried with the slashes going / and \ > > if i use this: > <!-- #include file=forum/includes/consts-inc.asp --> > i get this: > > for some information. i the file that gives the error is in the includes > folder, which is in the root web. the forum folder is also in the root web. > > so i am in folder unthe root, and trying to include a file from another > folder under the root. > > how can i do this?? > > > > > Jeff > > Steven Burn, May 9, 2006 3. Mike BrindGuest Jeff wrote: > I have an asp page. Now I know this is sortof OT, but I am not sure of the > forum to get an answer. > > I have an include on this asp page > > <!-- #include file=\forum\includes\consts-inc.asp --> > > now, it gives me this error: > slash or back slash. > > i can't use .. either, because it gives me this error:The Include file > '..\forum\includes\consts-inc.asp' cannot contain '..' to indicate the > parent directory. > > I tried with the slashes going / and \ > > if i use this: > <!-- #include file=forum/includes/consts-inc.asp --> > i get this: > > for some information. i the file that gives the error is in the includes > folder, which is in the root web. the forum folder is also in the root web. > Is includes in the web root or in the forums directory? What you've said is contradictory. If your includes is really in the web root do this: <!--#include virtual="includes/consts-inc.asp"--> If it is in the forums directory, which is in web root, do this: <!--#include virtual="forums/includes/consts-inc.asp"--> Oh, and your question is not OT. It's a general ASP question -- Mike Brind Mike Brind, May 9, 2006 4. Mike BrindGuest Jeff wrote: > Mike Brind wrote: > > Jeff wrote: > > > I have an asp page. Now I know this is sortof OT, but I am not sure of the > > > forum to get an answer. > > > > > > I have an include on this asp page > > > > > > <!-- #include file=\forum\includes\consts-inc.asp --> > > > > > > now, it gives me this error: > > > slash or back slash. > > > > > > i can't use .. either, because it gives me this error:The Include file > > > '..\forum\includes\consts-inc.asp' cannot contain '..' to indicate the > > > parent directory. > > > > > > I tried with the slashes going / and \ > > > > > > if i use this: > > > <!-- #include file=forum/includes/consts-inc.asp --> > > > i get this: > > > > > > for some information. i the file that gives the error is in the includes > > > folder, which is in the root web. the forum folder is also in the root web. > > > > > > > Is includes in the web root or in the forums directory? What you've > > said is contradictory. If your includes is really in the web root do > > this: > > > > <!--#include virtual="includes/consts-inc.asp"--> > > > > If it is in the forums directory, which is in web root, do this: > > > > <!--#include virtual="forums/includes/consts-inc.asp"--> > > > > Oh, and your question is not OT. It's a general ASP question > > > >well.. the forums is in the root... and of course forums/includes >isn't. my bad for wording that wrong. >i have this ><!--#include virtual="forums/includes/consts-inc.asp"--> >and still getting this > > >/includes/forum-inc.asp, line 37 > forums - plural > >i looked over the permissions and i don't see > >i know the file is there, as here is the path copied straight from >the tree. > >http://my.domain/forum/includes/consts-inc.asp > forum - singular So which is it? Is the directory called forum or forums (plural)? That's probably why the file can't be found. Please make sure you reply to the newsgroup in future, not the spam-trap email address I use here. The delay in responding is because I hardly ever look at that email account. Lucky for you, I was kind of bored this morning -- Mike Brind Mike Brind, May 15, 2006 1. includes in ASP .NET Geraldine, in forum: ASP .Net Replies: 1 Views: 424 Kevin Spencer Oct 29, 2003 2. WEBBOT includes and .ASPX Tor Nordahl, in forum: ASP .Net Replies: 0 Views: 482 Tor Nordahl Nov 4, 2003 3. Virtual Includes in ASP.NET Steve, in forum: ASP .Net Replies: 1 Views: 612 Jim Cheshire [MSFT] Nov 19, 2003 4. migrating asp to aspl.net: includes? Davíð Þórisson, in forum: ASP .Net Replies: 4 Views: 568 Davíð Þórisson Dec 30, 2003 5. Using includes with ASP.NET Jay, in forum: ASP .Net Replies: 1 Views: 583 =?Utf-8?B?am9obno=?=, in forum: ASP .Net Replies: 1 Views: 735 bruce barker Feb 27, 2004 7. Undecipherable Error Message: The base class includes the field 'ShowColor1'... Eric, in forum: ASP .Net Replies: 0 Views: 1,445 8. Runtime includes? Justin Weinberg, in forum: ASP .Net Replies: 0 Views: 491 Justin Weinberg May 13, 2004	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8225829005241394, "perplexity": 12541.460540558312}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-44/segments/1476988720973.64/warc/CC-MAIN-20161020183840-00117-ip-10-171-6-4.ec2.internal.warc.gz"}
https://codegolf.stackexchange.com/questions/189733/print-an-array-as-a-table	# Print an array as a table [closed] Write a program that prints an associative array (key-value) to a table. # Requirements • Standard loopholes are forbidden • Use box drawing characters to draw the table. • You can write both a full program or a function. • Key or value can't contain multiline strings. • Value/key can't be an array/associative array ( example: ["a"=>["a"=>"b"]] or ["a"=>["a","b"]] ) ## Special cases • If the programming language lacks of associative array , you can use a list of pairs. Example: [[key1,value1],[key2,value2]] • You can insert horizontal lines between successive pairs. • An input array can't be empty # Challenge Your code must draw a vertical table like in the example from a associative array . The key must be at left and value must be at right and them needs to be separed,you can choose how separe them. Every key-value pair must be in another row. There must be only 2 columns for the keys and value. # Example Array(PHP): ["a"=>"b","c"=>"d","d"=>"d"] Output: ┏━━━┓ ┃a┃b┃ ┃c┃d┃ ┃d┃d┃ ┗━━━┛ ## closed as unclear what you're asking by xnor, caird coinheringaahing, Mr. Xcoder, Sriotchilism O'Zaic, Jo KingAug 11 at 21:25 Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question. • If the language lacks associative arrays may we just use a list of pairs, [[k1,v1],[k2,v2],...], or a flat list [k1,v1,k2,v2,...]? – Jonathan Allan Aug 11 at 16:21 • @JonathanAllan If the language lacks associative arrays you can use a list of pairs ( [[k1,v1],[k2,v2]] ) . – Micio Informatico Aug 11 at 16:22 • Thanks, please edit the post accordingly (we prefer not to have spec in comments). Also what are the rules regarding justification? (e.g ["abba"=>"1","b"=>"20"]) – Jonathan Allan Aug 11 at 16:24 • Must it be a full program or can we write a function instead? – Purple P Aug 11 at 16:31 • Maybe for next time, use the sandbox to get all the questions answered before posting? – Adám Aug 11 at 16:37 # TryAPL, 1 byteSBCS Anonymous tacit prefix function. As TryAPL has no associative arrays, this takes a list of pairs as argument. ↑ Try APL! ↑ mix the list of pairs into a table • Question over, go home folks. – Purple P Aug 11 at 16:57 # J, 1 byte > So… to take strings as input they need to be in boxes already, and to make them pairs I think they need to be put into a box again so that they can be treated separately. I'm not too sure about the second part. Anyway, unboxing the whole thing gives the desired form. I get a sense that this could be a 0 byte answer if we twist the format enough (or maybe less, since a 2d array of boxes seems to be the proper input format instead of my weird format), but I don't understand boxing all that well. Try it online! # PHP, 563 bytes <?php $t = ["a"=>"b","c"=>"d"];$k = $v =$i = $j = 0; foreach ($t as $a =>$b){ $k = (strlen($a) > $k ? strlen($a) : $k);$v = (strlen($b) >$v ? strlen($b) :$v); } echo "┏"; for(; $i++ <$k + $v + 3;) echo "━"; echo "┓\n"; foreach ($t as $a =>$b){ echo "\|{$a} "; for($i = 0; $i <$k - strlen($a);$i++) echo " "; echo "\| {$b}"; for($i = 0; $i <$v - strlen($b);$i++) echo " "; echo "\|\n"; } echo "┗"; for(; $j++ <$k + \$v + 3;) echo "━"; echo "┛"; ?> Try it online! # Charcoal, 62 bytes Ｆ²⊞υ×━⌈ＥθＬ§κι⟦⪫┏┓⪫υ┳⟧Ｅθ⪫┃┃⪫Ｅι◨λＬ§υμ┃⪫┗┛⪫υ┻ Try it online! Link is to verbose version of code. Charcoal's code page doesn't include box-drawing characters so they cost 3 bytes but the code uses them instead of their three-byte encoding because it looks nicer. Takes input as an array of tuples as Charcoal doesn't have an iterable dictionary. Explanation: Ｆ²⊞υ×━⌈ＥθＬ§κι Find the length of the longest key and value and repeat ━ according to that length. ⟦⪫┏┓⪫υ┳⟧ Embed the ━s in ┏┳┓. Ｅθ⪫┃┃⪫Ｅι◨λＬ§υμ┃ For each tuple, pad the strings to the length of the ━s and wrap them with ┃s. ⪫┗┛⪫υ┻ Embed the ━s in ┗┻┛. # Python 3, 189172168173 169 bytes def f(d):t=d.items();a,b=map(lambdal:max(map(len,l)),t);c='─'a,'─'b;print("┌%s┬%s┐"%c,*[f"│{k:{a}}│{v:{b}}│"for k,v in t],"└%s┴%s┘"%c,sep="\n") Try it online!	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.193542942404747, "perplexity": 4026.899101356189}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-35/segments/1566027330913.72/warc/CC-MAIN-20190826000512-20190826022512-00371.warc.gz"}
https://iforest.sisef.org/contents/?id=ifor3693-014	## Density, extractives and decay resistance variabilities within branch wood from four agroforestry hardwood species iForest - Biogeosciences and Forestry, Volume 14, Issue 3, Pages 212-220 (2021) doi: https://doi.org/10.3832/ifor3693-014 Research Articles Agroforestry practices like pruning trees to control the light flux to crops produce every year a large volume of branches which is valorized by farmers as mulching or energy fuel. However, according to the literature, the wood of branches shows higher rates of polyphenols than stem wood and this can open some new perspectives for branch exploitation. In this study, the wood properties (density, mechanical properties, extractive content and decay resistance) were determined on branches of different sizes from oak, chestnut, poplar and walnut trees collected in two agroforestry systems. These properties were evaluated according to the wood age and the sampling position along the radial and longitudinal axes of the branch. All samples were analyzed by NIR-Spectroscopy and a predicting model aimed to assess the branch wood properties has been developed. Wood characteristics largely vary between species and do not exactly follow the same trends from one species to another. Overall, hardwood density of branches is similar to that of trunks, the content in wood extractives follows similar evolutions, and the decay resistance of branch wood does not seem to be really impacted by its position along the branch. Reliable NIRS models were built to easily predict the wood density and extractives content of agroforestry branches. The extractives content and the decay resistance of branch hardwood appear to be substantially lower than those of trunks, which suggests a non-suitability of branch wood for developing high-valued green chemistry. # Introduction In many tropical countries, agroforestry systems provide both services for agriculture and for non-food economic sectors (housing and energy). Agroforestry is defined as any landscape use system associating trees or any other ligneous perennial plants with animal and/or vegetal productions on the same surface unit ([40]). Such a system provide not only environmental but also economic and social benefits to farming communities ([39], [46]). Agroforestry play an important role in pests and pathogens control (World Agroforestry Centre - [23]), food security ([19]), soil protection and natural amendment ([58]), biodiversity conservation ([34]) and above all in climate change mitigation ([21]). Agroforestry trees differ from forestry trees in two ways: their roots dig deeper ([37]), and they also grow faster and produce more biomass, most likely because there is less competition for the light and other resources ([12]). In addition, agroforestry trees usually grow in more fertilized soils than those of forest trees. In some cases, an agroforestry tree will produce about three times more biomass than a tree of the same age in a forest ([15]). This increased biomass enables agroforestry trees to potentially stock large amounts of carbon, thereby ï¿¹contributing to mitigate the effects of climate change and providing a highly valuable woody resource to be used for various purposes. Since six decades, European countries (including France) have massively excluded trees from the cropfields in order to intensify mechanized agriculture. However, the current agro-ecological transition is going to reverse this trend through the design of new agroforestry systems. Besides agricultural products, the main product specific to agroforestry systems is wood. Trunks, branches and twigs all have different potential uses due to their diverse characteristics ([1]) which are summarized in Fig. S1 (Supplementary material). Throughout their life cycle, agroforestry trees mostly yield pruning wood from branches, which has the same wood orthotropic cylindrical organization as trunks (Fig. S1) and currently is mostly used as Ramial Chipped Wood (RCW) or animal litter ([31]). Branch wood has been poorly investigated compared to stem wood, and currently there is a lack of data which could support any potential added-value of the branches for any production path. Regarding the physical aspects, some studies reported that the mechanical characteristics of branches’ wood are usually reduced compared to those of the trunks ([20]). Other researchers investigated the density and anatomy of branches in several species ([11], [26]), finding that in most cases the wood density of branches seems to be higher than that of the trunks. Yet, this characteristic, as most of other wood characteristics, seems to be highly variable depending on the tree species considered. Such differences also appear when considering wood chemical properties, which strongly change moving from one tree organ to another. Tree knots along the stem have been particularly studied, resulting in most cases richer in extractives than trunks and branches both in hardwoods and softwoods ([27], [25]). Furthermore, branches seem to be richer in extractives than the trunk clear wood, although they are poorer than the knots ([57], [36]). They also present a higher durability than the trunks ([10]), due to the higher content of wood extractives. These are non-structural wood cell components of low molecular weight which act as natural chemical products mainly protecting lignocellulose from fungal and microbial attacks ([41]). This study investigated the potential of branch wood from agroforestry practices as base material to develop green chemistry and/or to manufacture biomaterials. Farmers prune their trees every year to manage light reaching the ground, and the harvested biomass can help improve the economic model of agroforestry plots. To test the suitability of such a woody biomass to the above goals, wood physical and chemical characteristics were investigated on branches from four species of agroforestry hardwoods collected in interplot systems (oak and chestnut) and in alley-cropped system (poplar and walnut). The evolution of wood density, extractives content and durability with the age of wood along the radial and longitudinal axes of the branches was assessed. These properties were then compared to those of wood from the trunk of the same trees. Additionally, all samples were analyzed by NIR-Spectroscopy with the aim of developing a fast system to assess the branch wood properties directly in the field. # Material and methods ## Tree selection The selected hardwoods species were sweet chestnut (Castanea Sativa Mill.), pedunculate oak (Quercus robur), hybrid walnut (Juglans × intermedia [C. DC.] Carrière, hybrid Juglans nigra × Juglans regia) and hybrid poplar (Populus generosa Henry). Chestnuts and oaks were sampled near Fougères, France (48° 21′ 05.62″ N, 01° 12′ 16.65″ W), while poplars and walnuts were sampled near Alès, France (44° 07′ 37.934″ N. 04° 05′ 0.067″ E). The sampled chestnuts and oaks were planted as grasslands’ hedges, whereas walnuts and poplars were planted within grasslands plots (intraplot). The selected trees were sampled in February 2019 to limit the seasonal impact on wood chemical composition (i.e., starch in sapwood). A total of 9 trees were sampled from which 15 branches were taken (one to three branches per tree). The details are summarized in Fig. 1. Fig. 1 - Sampling, processing and selection of wood samples. For each species, the harvested branches were split in three sectors according to their distance to the tree trunk. The three branch sectors were defined as follows: • Sector 1: 100% of the branch diameter at the knot’s level; • Sector 2: 70-90% ± 3% of the branch diameter at the knot’s level; • Sector 3: 40-70% ± 5% of the branch diameter at the knot’s level. A total of 45 branch sectors were sampled. The age of the branch wood is reported in Tab. 1, according to the tree species and the branch sector. Based on these data, we supposed than the majority of wood samples is mainly composed by sapwood portion or sometimes by transition wood, as for example in sector 1 for chestnut. Tab. 1 - Age of the branch wood according to the position sector in the branch for the four hardwood species. Branch Sector Age of the branch wood (years) Chestnut Oak Walnut Poplar Sector 1 9 ± 1 18 ± 4 14 ± 2 14 ± 5 Sector 2 8 ± 1 15 ± 2 13 ± 1 12 ± 5 Sector 3 6 ± 1 11 ± 1 12 ± 1 10 ± 4 ## Sample partitioning, conditioning and density measurement Each of the 45 branch sectors was firstly cut into diametric vertical planks (30 mm width) using a band saw (Fig. 1), taking care of including both normal and tension wood (wherever present). The planks were then cut into wood sticks (15 × 5 mm2) at four radial locations. The wood sticks were then cut into test pieces sized 25 × 15 × 5 mm3 (L: longitudinal; T: tangential; R: radial). These samples were stabilized at a moisture content (MC) of 12% in humid air at 20 °C ± 2 °C and 65 % ± 5 % RH. Air-dried density of samples was determined by weighing and measuring their volume using a vernier caliper, prior to further testing. Overall, 1080 samples were prepared and used as shown in Fig. 1. In addition, increment cores (5 mm in diameter, 20 cm long) were taken from the trunk of sampled trees near the insertion zone of branches (1 core per branch, totaling 15 cores samples). Each core was cut in three parts (5 mm in diameter, 25 mm long) that were used for extraction (using a protocol similar to that describe below), in order to compare the extractive content of the stem wood to that of the wood from the corresponding branches. ## Extraction processes All experimental procedures used in the determination of the extractive content were adapted, with minor modifications, from Rowell et al. ([45]). Each sample was dried at 103 °C to determine its initial anhydrous mass (m2) and then extracted in a soxhlet with Toluene : Ethanol (Sigma Aldrich, 32201-M) 2:1 (v:v) solution (2 × 6 h, intercalated by 15 h of maceration in the extraction solvents) following by distilled water (2 × 6 h, intercalated by 15 h of maceration in the extraction solvents), and then dried at 103 °C for 48 h to obtain the anhydrous mass (m3). The wood extractive content (E), in percentage of dry weight (DW), was determined according to the following equation (eqn. 1): $$E (\text{%} DW) = \frac{(m_2 - m_3)} {m_2} \cdot 100$$ where m2 is the theoretical anhydrous mass of the test piece before extractions and m3 is its anhydrous mass after the extractions. A total of 540 samples were characterized for their extraction rate. ## Decay resistance tests To carry out the durability screening test, the two following decay fungi were used: Trametes versicolor (L.) Lloyd (TV) and Coniophora puteana (Schumach.) P. Karst. (CP), respectively a white rot and a brown rot fungi. These two fungi has been selected because they are mandatory by the XP-CEN/TS-15083-1 ([56]) standard in the determination of natural decay resistance of hardwood species. Decay tests were performed according to the procedure described by Bravery ([3]). Sterile culture media were prepared with 40 ± 0.5 g of malt extract and 20 ± 0.5 g of powdered agar dissolved in 1 L of distilled water. They were then molded in glass containers, closed by cotton plugs to enable air circulation. The jellified culture media were inoculated with a piece of 1 cm in diameter. Then, the containers were incubated for two weeks in climatic chambers (22 ± 2 °C and 70 ± 5 % RH), until a full colonization of the medium by the mycelium was reached. Weight and humidity of the conditioned wood block samples were measured to determine their theoretical anhydrous mass (m4), and then sterilized in an autoclave at 121 °C by two successive steps of 20 min, before decay resistance tests. Two hundred seventy test pieces were tested per fungus. The incubation of test pieces was carried out for 8 weeks in a climatic chamber (22 ± 2 °C and 70 ± 5% RH). Once the fungal exposure was completed, samples were carefully cleaned from the fungus. All samples were then oven dried at 103 °C for 48 h and weighed (m5). Mass loss (ML, %) due to the decay degradation of the sample was calculated as (eqn. 2): $$ML (\text{%}) = \frac{m_4 - m_5} {m_4} \cdot 100$$ The wood durability classes were then attributed according to the XP-CEN/TS-15083-1 ([56]) standard. ## Near infrared spectroscopy measurements Near infrared spectra were obtained in the radial tangential plane of all test pieces, after a stabilization step performed at 20 °C ± 2 °C and 65 % ± 5 % RH. Chaix et al. ([5]) showed that regression models yield accurate predictions when measurements are made on this plane. A Bruker Vector 22/N® spectrophotometer (Bruker Co., Billerica, MS, USA) and the OPUS® software ver. 5.5 were used in diffuse reflectance mode with a sintered gold standard as reference. Data were measured for wavelengths between 9000 to 4000 cm-1 (1100 to 2500 nm), in 8 cm-1 increments. The spectra were composed by 648 wavelengths of reflectance values. Sixteen scans were performed and averaged for each measurement in order to improve the signal-to-noise ratio. ## Statistical analysis Statistical analysis was performed using the software RStudio Desktop® ver. 1.2 (RStudio Inc., Boston, MS, USA). To understand the evolution of the characteristics measured within branches, Kruskall-Wallis tests have been applied on each potential explicative factor and response variable. For each test indicating an effect of a factor on a studied variable, Wilcoxon tests were used to investigate the nature of this effect and the significance of the differences between different groups. NIRS spectra were first transformed ([38]) with a Standard Normal Variate (SNV) correction to reduce the effect of irregularities of surface and the intra spectrum variability (correction of the light dispersion). The second derivative was then computed using the algorithm of Savitzky Golay with a smoothing range of 21 data points and a third degree polynomial ([49]). The use of this derivative allowed to separate overlapping peaks and correct the baseline deviation of spectra. Mathematical corrections were applied using the software package “prospectr” ver. 0.1.3. NIRS models to predict the density, the extractive contents and the mass loss were developed with the Partial Least Squares (PLS) regression method using the software package “pls”, ver. 2.7.1. No outlier was removed in the models. The data was divided into two sets: a calibration set (2/3 of the total number of samples) and a validation set (1/3). The property values to predict were first sorted and the validation set was built by picking one sample on three. The k-fold cross validation method was used on the calibration set with 10 random segments. The quality of the models was given by computing the following parameters ([38]): the coefficient of determination of calibration (R²C), the standard error of calibration (SEC), the root mean square error of cross validation (RMSECV), the coefficient of determination of calibration (R²P), the root mean square error of prediction (RMSEP), the ratio of performance to deviation (RPD). # Results and discussions ## Prediction of the wood density and extractive content by NIRS modelling Fig. 2A presents the comparison of the density values predicted by PLS regression with the measured ones. Ten components were selected for the model. The coefficient of determination value was R²C = 0.91 (SEC = 0.04 g cm-3, RMSECV = 0.05 g cm-3) for the calibration set. The predictive performance of the model on the validation set was R²P = 0.89, with a RMSEP value of 0.05 g cm-3. The values of SEC, RMSECV and RMSEP were sufficiently close and showed that the model was robust. The value of the ratio of performance to deviation was RPD = 3.0, highlighting that this model was suitable for predictions ([55]). These results were in agreement with previous published studies ([17], [50], [35], [22], [29]). Schimleck et al. ([50]) showed that it was possible to accurately calibrate NIR models for a wide range of species that represent different taxa, wood chemistry and physical properties. NIR absorbance spectra are related to the chemical composition of the tested wood sample ([29]). The NIR spectroscopy technique is usable in assessing wood physical properties (including density) because these properties vary with the chemical properties within a tree, but also because the infrared light contains information of chemical components (light absorption) associated with physical characteristics (light scattered) like surface texture or porosity ([4], [51], [47]). Fig. 2 - Relationship between measured and predicted density (A) and branch wood extractive content (B) by NIRS modelling. (a) Calibration set with different marks by species; (b) calibration and validation set (white circle: calibration set; black circles: validation set). Continuous lines represent regression lines, while dotted lines are the identity lines (y = x). Fig. 2B shows the result of the PLS regression to predict the extractive contents. The model was built with 7 components, and the R²C value was 0.86 (SEC = 0.95% and RMSECV = 1.05%) for the calibration set. The coefficient of determination for the validation set was R²P = 0.85, with a RMSEP value of 0.96%. As with density, this model was found to be robust, and the value of the ratio RPD was 2.6. Investigations on wood chemical composition, specifically on extractive contents, using NIR were previously reported ([33], [13], [16], [54], [44]). Our results are in agreement with the findings of the aforementioned studies. Wood extractives include heterogeneous groups of chemical compounds, and they can be grouped by the type of solvent used during their extraction ([16], [44]). Gierlinger et al. ([16]) developed NIR models on wood powder and on solid wood to determine the hot water and acetone extractive content of Larix sp. The authors stated that the solid wood models were less predictive than those derived from wood powder because additional factors, such as the varying wood structure (e.g., earlywood vs. latewood within annual rings), sample geometry or surface properties, might add to the existing complex chemistry. The characteristics of the models related to solid wood were R²P = 0.74 (RMSEP = 1.88%) for the hot water extractives contents, and R²P = 0.78 (RMSEP = 0.36%) for the acetone extractive content. A multi-species model was developed by Razafimahatratra et al. ([44]) to determine the ethanol-toluene extractive contents with a portable spectrometer. The main characteristics were a coefficient of determination of cross validation of 0.64 and a RMSECV value of 1.54%. The authors reported that the quality of the model was linked to the restricted spectral range and resolution of the portable spectrometer. The quality of the model might also have been the result of mixing of different chemical signature between species, adding to quantitative variations of composition within each chemical signature in each species. ## Predictability of the fungal durability by NIRS modelling Wood degradation is a topic of high interest in NIR wood research because it allows the detection of chemical changes as spectral variation ([54]). Fackler & Schwanninger ([14]) used NIR spectroscopy to investigate the overtones of C-H and O-H stretching vibrations; in particular, to better understand degradation processes of lignin, cellulose and hemicelluloses during brown rot. The mass losses induced by brown rots (Coniophora puteana, Gloeophyllum trabeum) and a white rot (Trametes versicolor) were predicted by NIRS measurements on Sequoia sempervirens (D. Don) Endl. samples ([24]). The spectra were acquired on the radial-longitudinal face of wood blocks. The authors found RPD ratios in cross-validation between 1.3 to 1.4, and stated that the models could be used to separate the heartwood for high and low values of mass loss with fungal decay testing. Sykacek et al. ([53]) investigated the natural durability of Larix spp. using the test fungi Gloeophyllum trabeum and Coniophora puteana. The authors obtained a coefficient of determination from cross validation of 0.93 and a RMSEP value of 3.3% for Coniophora puteana (with radial surface tests and a second derivative pre-processing). In the present study, the regression coefficients between the data predicted by NIRS models and the observed data are very low when all the species are considered together (0.43 and 0.53 for TV and CP, respectively). The white rot induced mass loss is approached with a precision of ± 11% of the dry weight, and the brown rot induced mass loss with a precision of ± 7%. Those precision levels are insufficient to reliably determine the durability classes of the wood. In that case, the NIRS models cannot be used to build reliable prediction models of the white and brown rot induced mass losses. NIRS provides measures directly linked to the chemistry of the wood since it measures chemical bonds. As a consequence, it is expected that reliable models could be built to accurately assess the wood biochemical composition (i.e., extractive content) and its density, which is strongly correlated to this first variable. Although wood extractives and density are often correlated with wood durability, the NIRS models do not accurately predict the decay resistance of branch wood. The chemical composition of the extractive fraction of wood (chemical signature) largely depend on the woody species and this could explain the difficulty to build an accurate NIRS models to predict the fungal durability of wood. ## Variability of branches wood air-dried density ### Variations between branches The wood density of branches appeared different both among and within species. Oak branches wood (0.76 ± 0.06 g cm-3) resulted to be denser than walnut (0.68 ± 0.04), chestnut and poplar wood (0.59 ± 0.07 and 0.48 ± 0.07 g cm-3, respectively). Regarding the oak samples, the wood densities of the branches F0 and F2 (0.78 ± 0.04 and 0.80 ± 0.06 g cm-3, respectively) significantly differed from those of the branches G1 and G2 (0.74 ± 0.04 and 0.72 ± 0.06 g cm-3, respectively) after the Wilcoxon tests, while there are no significant density variations between the branches of the oak F or between those of the oak G. Likewise, the chestnut branches of the trees A and C, and the poplar branches of the trees J and K all displayed significantly different densities. This intra-species density variation was not detected for walnut trees. For the studied species, the wood density was similar for all the branches within a single tree. ### Variations inside branches Within a branch, the wood density varied with the location of the wood. Fig. 3 shows that the variation of wood density with the distance from the trunk depends on the species. Unless for poplar, the wood that was closest to the trunk (sector 1: 0.67 ± 0.13 g cm-3 on average) showed a significantly higher density than woods located further away from it (sectors 2 and 3: 0.61 ± 0.12 and 0.61 ± 0.11 g cm-3 on average, respectively). Concerning the radial location of the wood (Fig. 3), it appeared that the wood density of chestnut and poplar branches increases with the distance to the pith: the closest to the bark, the denser the wood is. The same tendency can be observed for oak, but neither for it nor for walnut wood does the distance to the pith significantly affect the density. It is rather clear that the variation in wood density along the radius is very different among species. For example some wood species like Dicorynia guianensis Amshoff show nearly no variations, while Parkia nitida Miq. has a density variation from 0.2 to 0.5 between pith and bark, within the trunk ([30]). Fig. 3 - Mean density of branch wood in four hardwood species as a function of the distance to the trunk (left column) and to the pith (right column). Bars followed by the same letter are not significantly different. Overall, branch wood density significantly decreases with the distance to the trunk and significantly increases with the distance to the pith. For all the considered species, the wood density is quite similar between trunks and branches but this point is to be confirmed with specific trials. Sarmiento et al. ([48]) highlighted that trunk and branch xylem densities of various French Guiana tree species were significantly and positively correlated with radial and longitudinal position within the branch or the trunk. Branch wood density decreases when the distance to the trunk increases (Fig. 3). The fact that the sections of wood furthest from the trunk likely contain more juvenile wood than those closest to the trunk could explain this phenomenon. Gryc et al. ([18]) and Latorraca et al. ([28]) showed that the juvenile wood of 115 old-grown Norway spruce (Picea abies Karst.), 98 old-grown Scots pine (Pinus sylvestris L.) and 80 old-grown European larch (Larix decidua Mill.) from the Czech Republic and 14 old-grown Black locust (Robinia pseudoacacia L.) trees from different forest sites in Eastern-Germany and Eastern Hungary, is produced during the first five year of life of the tree and it is less dense, less rich in extractives and less durable than mature wood which is produced later. However, such tendency is not so clear for all species and all growing conditions. There are very few evidence of typical variations in extractive content associated to juvenility, mainly because the deposition of extractives in the heartwood occurs much later than the thickening of the cell walls. On old trees with good durability, the resistance to rot is often much lower near the pith but this is mostly due to the age of the heartwood and its extractives near the pith. In addition, the wood density is related to the tree structure ([2]) and the trunk/branch junction has to be strong and resistant to degradation, with mechanical stresses very different from the trunk, due to the inclined growing of the branch. The studied wood characteristics also present a radial pattern within branches that follows the same pattern as within trunks. McLean et al. ([32]) noticed in tropical woods growing in dense forests that the wood density increases with its distance from the pith, but this is not true for the same species growing in open conditions like in plantations. Our result suggest that the same pattern is to be found on branch wood, as the average wood density next to the pith is significantly lower than that recorded at the distal end of the branch. ## Variability of extractive contents of branch woods ### Variation among branches As shown in Fig. 4, the wood extractive contents were the highest in oak branches and slightly lower in walnut branches, while being still significantly higher in these than in poplar and chestnut branches. Within species, the extractive content of branch wood did not significantly differ, neither among the same trees nor among different trees. Considering all species, the extractive content seems to be lower in the branches than in the knots and even than in the trunk (Tab. 2), according to the findings of Kebbi-Benkeder ([25]). This tendency has been confirmed in oaks and walnuts in this study. The extractive content has been evaluated on increment cores sampled in the trunk near the branch insertion zone and in the sapwood area (near the bark). On average, oak branches contained 7.9 ± 1.5% of extractives and their corresponding samples from the nearby trunk contained 10.6%. Walnut branches contained 5.4 ± 0.9% of wood extractives while their trunk had 7.62%. Chestnut and poplar branches were the poorest in wood extractives as they only contained 3.2 ± 0.9% and 2.0 ± 0.8% of those, respectively. Fig. 4 - Mean extractive content of branch wood in four hardwood species as a function of the distance to the trunk (left column) and to the pith (right column). Bar followed by the same letter are not significantly different. Tab. 2 - Mean content of wood extractives (% dry weight) in the knots and clear heartwood of the four hardwood species (from [25] and [42], [43]). Component Chestnut Holm Oak Walnut Poplar Knots (average of young, mild, old knots) 17.4 14.2 10.9 < 10 Trunk heartwood 10.3 12.7 13.3 < 7 Trunk sapwood 7.3 9.3 6.3 - ### Variation within branches Oak and chestnut extractive rates tended to increase with distance from the trunk (Fig. 4), but this tendency was only significant between the group of the two first sectors and the last one and did not appear in the case of walnut and poplar branches. In the radial direction, chestnut and poplar showed a slight but significant increase of extractive rates with the distance from the pith of the branches (Fig. 4). Such an evolution did not appear in the case of walnut and oak wood, which had the same extractive content level in the three radial positions. Globally, the variation of extractive contents linked to the distance from the pith is quite low and never exceed +1%. Pooling the data of the four hardwoods species altogether, it appeared that the distance to the trunks did not significantly impact on the wood extractive contents. However, the radial locations of the wood in the branch did slightly differ in extraction contents, which increased when approaching the bark (5.3 ± 2.5%), perhaps showing a bark neighborhood effect, as the bark is usually rich of extractives. In addition, there are strong differences in extractives in the sapwood, which can be due to nutrients like starch with high levels of variation depending on the season, and in the heartwood where extractives are mainly defense products with no significant variation among seasons. ## Variability of fungal decays of branch woods ### White rot (Trametes versicolor - TV) Wood mass loss induced by white rot showed a large variation (Fig. 5A). Walnut wood showed the highest range of values (median value of 39.0%), followed by poplar (median value of 35.4 %) and chestnut (median value of 34.4%) then oak (median value of 28.2 %), which was in this case the most durable wood. Fig. 5 - Natural durability of branch wood exposed to (A) Trametes versicolor (L.) Lloyd. and for (B) Coniophora puteana (Schumach.) P. Karst. (1, 2, 3): position of the wood sample along the branch, in order of increasing distance from the trunk (see text for further details). (<33, 33-66, >66%): radial position of the wood sample within the branch diameter, in order of increasing distance from the pith. According to wood durability classes regarding white rot (Tab. 3), it seems that for all wood species, the durability of heartwood and sapwood from branches was particularly lower than that recorded for the trunk heartwood. Tab. 3 - Mean values and standard deviations (SD) of mass loss due to fungal degradation and the associated wood durability classes (according to [56]) against Trametes versicolor (L.) Lloyd (TV) and Coniophora puteana (CP) and comparison with the durability class of trunk wood from similar woody species (: [6], [7], [8], [9]). Wood origin Parameter Species Chestnut Oak Walnut Poplar Branches Mean Mass loss due to TV (%) 34.4 28.2 39.0 35.4 SD Mass loss due to TV (%) 0.2 0.1 0.1 0.1 Durability class - TV 5 4 5 5 Mean Mass loss due to CP (%) 10.4 17.7 22.60 19.5 SD Mass loss due to CP (%) 0.1 0.1 0.1 0.1 Durability class - CP 3 4 4 4 Durability class 5 4 5 5 Trunk Durability class (CIRAD) 2 2 3 3 ### Brown rot (Coniphora puteana - CP) A tendency similar to that observed with TV can also be detected with CP (Fig. 5B), mainly in oak (except for the wood near the pith) and chestnut wood; indeed, we found a decrease of durability when the ratio of sapwood grows (Fig. 5B). Pooling the data obtained for all the species, the distance to the trunk significantly affected the wood durability, which is in contrast with what observed when the radial position was considered (Fig. 6). Fig. 6 - Median mass loss (% of dry weight) of branch hardwood, depending on the infecting fungi and the distance to the trunk (A) and to the pith (B). Values followed by the same letter are not significantly different. Wood durability tended to decrease from the trunk to the branch extremity and from the pith to the bark. This trend mainly concerned chestnut and walnut, and is likely due to the higher ratio of sapwood when moving from the trunk to the branch ends or from the pith to the bark. When the data obtained for all the four species were pooled, the distances to the trunk and to the pith had a significant effect on branch wood durability (Fig. 6). Globally, the durability of the four hardwoods regarding brown rot fungi was higher than that towards white rot fungi, which is consistent with previous findings reported in the literature ([52]). Overall, the averages of mass loss were 17.6% and 34.2% for CP and TV, respectively. Walnut was always the less durable species, whilst oak the more durable to white rot and chestnut the more resistant to brown rot. Our results showed that the coefficient of variation is higher for extractive contents than for density in almost every case. This was expected to some extent, as the variation of mass loss due to degradation is linked to both the chemical variation in the nature and the content of extractives and to the action of the fungi itself. Therefore, even for wood from the same tree with very similar chemical composition, rather large CV values can be observed. The large dispersion of ML values could be due to the wide range of diameters and ages of the branches sampled in this study. The durability screening tests ideally require the presence of several growth rings on a single sample and the test pieces were often too small to meet this requirement, which can lessen the precision of the results. Further, the measures were based on the dry weight of wood samples and, with a thickness of 5 mm only, it is possible that the sole manipulation of the test pieces altered their relative humidity, thus introducing a bias in the observed results. # Conclusion This study provides new knowledge on branch wood from agroforestry systems, which are still under-studied so far. The results obtained highlight the evolution and variability of the physical and chemical characteristics of branch wood from agroforestry hardwoods. As reported by previous studies, wood density was quite similar in branches and in trunks. Indeed, the wood density along the branches decreased with the distance to the trunk and slightly increased with the distance to the pith. A similar pattern was observed for the extractive content of wood, but at a much lower level in branches than in trunks. According to the literature, also wood durability of the four hardwood species was much lower in branches than in trunks, but it seemed to decrease with the distance to the trunk and the pith. These last observations should be considered cautiously and additional experiments with bigger test pieces should be done to consolidate these conclusions. Ultimately, this study did not reveal any manifest suitability of branch wood from agroforestry practices for green chemistry, because of the quite low extractive ratios. However, further studies on the composition of wood extractive might throw light on the possible existence of molecule of interest in branch wood. Although woods from trunk and branches have a similar chemical signature for each given species, the content level of some chemical compounds may be higher in the branches than in the trunk. Furthermore, wood density in branches is equivalent to that of trunks, which suggest similar mechanical characteristics. This support the hypothesis that branch wood has an unused potential, in particular to manufacture biomaterials. Yet, the low extractive content and low durability levels of branch wood hamper its use in outdoor conditions. However, the wood of branches of these agroforestry species can be implemented as structural material in use classes 1 and 2, and 3 depending on the species, permeability and final use. # Acknowledgements This work was financially supported by the French Environment and Energy Management Agency (ADEME) within the frame of the AGROBRANCHE (2018-2021) project (“Study of the valuation of branches in agroforestry for bio-based materials and green chemistry”). # References (1) ADEME/Atlanbois (2016). Wood energy: current resources and prospects, keys to action? Environment and Energy Management Agency - ADEME, Pays de la Loire, France, pp. 4. 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Aspen knots, a rich source of flavonoids. Journal of Wood Chemistry and Technology 26 (3): 245-258. CrossRef \| Gscholar (43) Pietarinen SP, Willför SM, Ahotupa MO, Hemming JE, Holmbom BR (2006b). Knotwood and bark extracts: strong antioxidants fromwaste materials. Journal of Wood Science 52 (5): 436-444. CrossRef \| Gscholar (44) Razafimahatratra AR, Rakotovololonalimanana H, Thévenon MF, Belloncle C, Chaix G, Ramananantoandro T (2018). Natural durability, ethanol-toluene extractives and phenol content prediction of eight wood species from Madagascar using NIRS multispecific models. In: Proceedings of the “Annual Meeting of the International Research Group on Wood Protection (IRG49)”. Johannesburg (South Africa) 29 Apr-3 May 2018. IRG, Stockholm, Sweden, pp. 6. Online \| Gscholar (45) Rowell RM, Pettersens R, Han JS, Rowell JS, Tshabalala MA (2005). Cell wall chemistry. In: “Handbook of Wood Chemistry and Wood Composites”. CRC Press, Boca Raton, FL, USA, pp. 35-72. Online \| Gscholar (46) Sanchez PA (1995). Science in agroforestry. Agroforestry Systems 30: 5-55. CrossRef \| Gscholar (47) Sandak J, Sandak A, Meder R (2016). Assessing trees, wood and derived products with near infrared spectroscopy: hints and tips. Journal of Near Infrared Spectroscopy 24: 485-505. CrossRef \| Gscholar (48) Sarmiento C, Patiño S, Paine CET, Beauchêne J, Thibaut A, Baraloto C (2011). Within-individual variation of trunk and branch xylem density in tropical trees. American Journal of Botany 98 (1): 140-149. CrossRef \| Gscholar (49) Savitzky A, Golay MJE (1964). Smoothing and differentiation of data by simplified least squares procedures. Analytical Chemistry 36: 1627-1639. CrossRef \| Gscholar (50) Schimleck L, Evans R, Ilic J (2003). Application of near infrared spectroscopy to the extracted wood of a diverse range of species. IAWA Journal 24 (4): 429-438. CrossRef \| Gscholar (51) Schwanninger M, Rodrigues JC, Fackler K (2011). A review of band assignments in near infrared spectra of wood and wood components. Journal of Near Infrared Spectroscopy 19 (5): 287-308. CrossRef \| Gscholar (52) Sun G, Ibach RE, Faillace M, Gnatowski M, Glaeser JA, Haight J (2017). Laboratory and exterior decay of wood-plastic composite boards: voids analysis and computed tomography. Wood Material Science and Engineering 12: 263-278. CrossRef \| Gscholar (53) Sykacek E, Gierlinger N, Wimmer R, Schwanninger M (2006). Prediction of natural durability of commercial available European and Siberian larch by near-infrared spectroscopy. Holzforschung 60: 643-64. CrossRef \| Gscholar (54) Tsuchikawa S, Kobori H (2015). A review of recent application of near infrared spectroscopy to wood science and technology. Journal of Wood Science 61: 213-220. CrossRef \| Gscholar (55) Williams P, Sobering D (1993). Comparison of commercial near infrared transmittance and reflectance instruments for analysis of whole grains and seeds. Journal of Near Infrared Spectroscopy 1: 25-32. CrossRef \| Gscholar (56) XP-CEN/TS-15083-1 (2006). Durability of wood and wood-based products - Determination of the natural durability of solid wood against wood destroying fungi - Test methods - Part 1: Basidiomycetes. European Committee for Standardization (CEN), Brussels, Belgium, pp. 20. Gscholar (57) Xu F, Zhong XC, Sun RC, Lu Q, Jones GL (2007). Chemical composition, fiber morphology, and pulping of P. bolleana Lauche. Wood and Fiber Science 38: 512-519. Gscholar (58) Young A (1991). Agroforestry for soil conservation. In: “Science and Practice of Agroforestry”. CAB International, Wallingford, UK, pp. 318. Gscholar # Supplementary Material #### Authors’ Affiliation (3) Remy Marchal 0000-0002-5712-9978 “Arts et Metiers” Institute of Technology, LABOMAP, HESAM University, F-71250 Cluny (France) Kevin Candelier #### Citation Terrasse F, Brancheriau L, Marchal R, Boutahar N, Lotte S, Guibal D, Pignolet L, Candelier K (2021). Density, extractives and decay resistance variabilities within branch wood from four agroforestry hardwood species. iForest 14: 212-220. - doi: 10.3832/ifor3693-014 Luigi Todaro #### Paper history Accepted: Mar 01, 2021 First online: May 02, 2021 Publication Date: Jun 30, 2021 Publication Time: 2.07 months © SISEF - The Italian Society of Silviculture and Forest Ecology 2021 #### Breakdown by View Type (Waiting for server response...) #### Article Usage Total Article Views: 770 (from publication date up to now) Breakdown by View Type HTML Page Views: 345 Abstract Page Views: 110 Web Metrics Days since publication: 42 Overall contacts: 770 Avg. contacts per week: 128.33 Article citations are based on data periodically collected from the Clarivate Web of Science web site (last update: Apr 2021) (No citations were found up to date. 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https://worldwidescience.org/topicpages/a/atmospheric+oxidation+by-products.html	#### Sample records for atmospheric oxidation by-products 1. Study of Atmospheric Nitric Oxide Science.gov (United States) Dalgarno, A. 1998-01-01 We investigated the contribution of energetic nitrogen atoms to the production of nitric oxide in the thermosphere and their influence on the infrared emission spectrum. The nitric oxide molecules are important contributors to the cooling of the atmosphere. We first pointed out that in determining the energy distribution of the nitrogen atoms, it is important to take into account the thermal motion of the atmospheric gases. It had been ignored in all earlier studies. The source spectra are broadened considerably by the center of mass motion of the reactants. We worked out the consequences for the production of nitric oxide at night, using as sources of energetic N atoms, NO(+) + e yield N + O, N(D-2) + O yield N + O. The high energy tail is enhanced by orders of magnitude. We had earlier suggested (Sharma et al. 1993) that the reaction of energetic nitrogen atoms with O2 was responsible for the rotationally enhanced NO identified in the infrared spectrum. Our calculations provided quantitative confirmation of the suggestion. We proceeded to explore the validity of another approximation used in earlier analyses, the hard sphere approximation for the energy loss in elastic collisions. We carried out precise quantum mechanical calculations of the elastic 2 differential scattering of nitrogen atoms in collisions with oxygen atoms and showed that although the hard sphere approximation was nowhere of high precision, reasonable results could be obtained with an effective cross section of 6 x 10(exp 15)sq cm. We also initiated a program to include inelastic energy loss processes in the determination of the energy distribution function. We began a calculation of the rotation and vibrational excitation cross sections of molecular nitrogen and nitrogen atoms and developed a method for including inelastic energy loss as a function of scattering angle in the Boltzmann equation. A procedure for obtaining the solution of the Boltzman equation was worked out. 2. Atmospheric oxidation of selected hydrocarbons Energy Technology Data Exchange (ETDEWEB) Benter, T.; Olariu, R.I. 2002-02-01 This work presents investigations on the gas-phase chemistry of phenol and the cresol isomers performed in a 1080 l quartz glass reactor in Wuppertal and in a large-volume outdoor photoreactor EUPHORE in Valencia, Spain. The studies aimed at clarifying the oxidation mechanisms of the reactions of these compounds with OH and NO{sub 3} radicals. Product investigations on the oxidation of phenol and the cresol isomers initiated by OH radicals were performed in the 1080 l quartz glass reactor with analyses by in situ FT-IR absorption spectroscopy. The primary focus of the investigations was on the determination of product yields. This work represents the first determination and quantification of 1,2-dihydroxybenzenes in the OH oxidation of phenolic compounds. Possible reaction pathways leading to the observed products have been elucidated. (orig.) 3. Atmospheric oxidation of selected alcohols and esters Energy Technology Data Exchange (ETDEWEB) Becker, K.H.; Cavalli, F. 2001-03-01 The decision whether it is appropriate and beneficial for the environment to deploy specific oxygenated organic compounds as replacements for traditional solvent types requires a quantitative assessment of their potential atmospheric impacts including tropospheric ozone and other photooxidant formation. This involves developing chemical mechanisms for the gasphase atmospheric oxidation of the compounds which can be reliably used in models to predict their atmospheric reactivity under a variety of environmental conditions. Until this study, there was very little information available concerning the atmospheric fate of alcohols and esters. The objectives of this study were to measure the atmospheric reaction rates and to define atmospheric reaction mechanisms for the following selected oxygenated volatile organic compounds: the alcohols, 1-butanol and 1-pentanol, and the esters, methyl propionate and dimethyl succinate. The study has successfully addressed these objectives. (orig.) 4. Greenhouse effect due to atmospheric nitrous oxide Science.gov (United States) Yung, Y. L.; Wang, W. C.; Lacis, A. A. 1976-01-01 The greenhouse effect due to nitrous oxide in the present atmosphere is about 0.8 K. Increase in atmospheric N2O due to perturbation of the nitrogen cycle by man may lead to an increase in surface temperature as large as 0.5 K by 2025, or 1.0 K by 2100. Other climatic effects of N2O are briefly discussed. 5. Primary atmospheric oxidation mechanism for toluene. Science.gov (United States) Baltaretu, Cristian O; Lichtman, Eben I; Hadler, Amelia B; Elrod, Matthew J 2009-01-01 The products of the primary OH-initiated oxidation of toluene were investigated using the turbulent flow chemical ionization mass spectrometry technique at temperatures ranging from 228 to 298 K. A major dienedial-producing pathway was detected for the first time for toluene oxidation, and glyoxal and methylglyoxal were found to be minor primary oxidation products. The results suggest that secondary oxidation processes involving dienedial and epoxide primary products are likely responsible for previous observations of glyoxal and methylglyoxal products from toluene oxidation. Because the dienedial-producing pathway is a null cycle for tropospheric ozone production and glyoxal and methylglyoxal are important secondary organic aerosol precursors, these new findings have important implications for the modeling of toluene oxidation in the atmosphere. 6. Primary atmospheric oxidation mechanism for toluene. Science.gov (United States) Baltaretu, Cristian O; Lichtman, Eben I; Hadler, Amelia B; Elrod, Matthew J 2009-01-01 The products of the primary OH-initiated oxidation of toluene were investigated using the turbulent flow chemical ionization mass spectrometry technique at temperatures ranging from 228 to 298 K. A major dienedial-producing pathway was detected for the first time for toluene oxidation, and glyoxal and methylglyoxal were found to be minor primary oxidation products. The results suggest that secondary oxidation processes involving dienedial and epoxide primary products are likely responsible for previous observations of glyoxal and methylglyoxal products from toluene oxidation. Because the dienedial-producing pathway is a null cycle for tropospheric ozone production and glyoxal and methylglyoxal are important secondary organic aerosol precursors, these new findings have important implications for the modeling of toluene oxidation in the atmosphere. PMID:19118482 7. Oxidation and Assimilation of Atmospheric Methane by Soil Methane Oxidizers OpenAIRE Roslev, P.; Iversen, N.; Henriksen, K. 1997-01-01 The metabolism of atmospheric methane in a forest soil was studied by radiotracer techniques. Maximum (sup14)CH(inf4) oxidation (163.5 pmol of C cm(sup-3) h(sup-1)) and (sup14)C assimilation (50.3 pmol of C cm(sup-3) h(sup-1)) occurred at the A(inf2) horizon located 15 to 18 cm below the soil surface. At this depth, 31 to 43% of the atmospheric methane oxidized was assimilated into microbial biomass; the remaining methane was recovered as (sup14)CO(inf2). Methane-derived carbon was incorporat... 8. A new method for quantitatively characterizing atmospheric oxidation capacity Institute of Scientific and Technical Information of China (English) CHENG YanLi; WANG XueSong; LIU ZhaoRong; BAI YuHua; LI JinLong 2008-01-01 Based on atmospheric chemical kinetics, the rate constant of overall pseudo-first order oxidation re-moval of gaseous pollutants (Kpor.T) is proposed to characterize the atmospheric oxidation capacity in troposphere. Being a quantitative parameter, Kpor,T can be used to address the issues related to at-mospheric oxidation capacity. By applying this method, the regional oxidation capacity of the atmos-phere in Pearl River Delta (PRD) is numerically simulated based on CBM-Ⅳ chemical mechanism. Re-sults show the significant spatio-temporal variation of the atmospheric oxidation capacity in PRD. It is found that OH initiated oxidations, heterogeneous oxidation of SO2, and photolysis of aldehydes are the three most important oxidation processes influencing the atmospheric oxidation capacity in PRD. 9. A new method for quantitatively characterizing atmospheric oxidation capacity Institute of Scientific and Technical Information of China (English) 2008-01-01 Based on atmospheric chemical kinetics, the rate constant of overall pseudo-first order oxidation re-moval of gaseous pollutants (Kpor,T) is proposed to characterize the atmospheric oxidation capacity in troposphere. Being a quantitative parameter, Kpor,T can be used to address the issues related to at-mospheric oxidation capacity. By applying this method, the regional oxidation capacity of the atmos-phere in Pearl River Delta (PRD) is numerically simulated based on CBM-IV chemical mechanism. Re-sults show the significant spatio-temporal variation of the atmospheric oxidation capacity in PRD. It is found that OH initiated oxidations, heterogeneous oxidation of SO2, and photolysis of aldehydes are the three most important oxidation processes influencing the atmospheric oxidation capacity in PRD. 10. Removing of Disinfection By-Product Precursors from Surface Water by Using Magnetic Graphene Oxide. Directory of Open Access Journals (Sweden) Zhongmou Liu Full Text Available The magnetic graphene oxide (MGO was successfully synthesised by the in situ chemical co-precipitation method with Fe3+, Fe2+ and graphene oxide (GO in laboratory and, was used as an adsorbent for disinfection by-product (DBP precursors removing from four natural surface water samples. The results indicate that various DBPs formation significantly decreased by 7-19% to 78-98% for the four samples after MGO treatment and, the treatment process was rapidly reached equilibrium within 20 minutes. The DBP precursors removal efficiency decreased with the increasing pH value from 4 to 10. Hydrophobic compounds (humic acid and fulvic acid are more sensitive to MGO, whereas hydrophilic and nitrogenous compounds (aromatic proteins are more insensitive. MGO could be regenerated by using 20% (v/v ethanol and, the DBP precursors removal efficiency can stay stable after five cycles. These results indicate that MGO can be utilized as a promising adsorbent for the removal of DBP precursors from natural surface water. 11. High Performance Nitrous Oxide Analyzer for Atmospheric Research Project Data.gov (United States) National Aeronautics and Space Administration — This project targets the development of a highly sensitive gas sensor to monitor atmospheric nitrous oxide. Nitrous oxide is an important species in Earth science... 12. Removal of disinfection by-product precursors with ozone-UV advanced oxidation process. Science.gov (United States) Chin, A; Bérubé, P R 2005-05-01 The efficacy of using ozone (O3), ultraviolet irradiation (UV) and the combined O3-UV advanced oxidation process (AOP) to remove 2 classes of disinfection by-product (DBP) precursors from raw surface water samples have been evaluated and compared. In particular, trihalomethane and haloacetic acids formation potentials were measured. Laboratory batch scale experiments were carried out as a function of ozone and UV dosage in order to study the removal kinetics. It is concluded that the combined O3-UV AOP is more effective than either the ozone or UV treatment alone. Ozone-UV AOP is capable of mineralizing up to 50% of the total organic carbon from the raw source water at an ozone dose of 0.62+/-0.019 mg O3/mL and a UV dose of 1.61 W s/cm2. In addition, O3-UV AOP can reduce trihalomethane formation potential by roughly 80% and haloacetic acids formation potential by roughly 70% at the same ozone and UV dosage. 13. Occurrence of by-products of strong oxidants reacting with drinking water contaminants--scope of the problem. OpenAIRE Rice, R G; Gomez-Taylor, M 1986-01-01 This paper describes results of a detailed literature review of the organic and inorganic by-products that have been identified as being formed in aqueous solution with four of the strong oxidizing/disinfecting agents commonly employed in drinking water treatment. These agents are: chlorine, chlorine dioxide, chloramine, and ozone. Significant findings include the production of similar nonchlorinated organic oxidation products from chlorine, chlorine dioxide, and ozone. In addition, all three... 14. A new atmospherically relevant oxidant of sulphur dioxide. Science.gov (United States) Mauldin, R L; Berndt, T; Sipilä, M; Paasonen, P; Petäjä, T; Kim, S; Kurtén, T; Stratmann, F; Kerminen, V-M; Kulmala, M 2012-08-01 Atmospheric oxidation is a key phenomenon that connects atmospheric chemistry with globally challenging environmental issues, such as climate change, stratospheric ozone loss, acidification of soils and water, and health effects of air quality. Ozone, the hydroxyl radical and the nitrate radical are generally considered to be the dominant oxidants that initiate the removal of trace gases, including pollutants, from the atmosphere. Here we present atmospheric observations from a boreal forest region in Finland, supported by laboratory experiments and theoretical considerations, that allow us to identify another compound, probably a stabilized Criegee intermediate (a carbonyl oxide with two free-radical sites) or its derivative, which has a significant capacity to oxidize sulphur dioxide and potentially other trace gases. This compound probably enhances the reactivity of the atmosphere, particularly with regard to the production of sulphuric acid, and consequently atmospheric aerosol formation. Our findings suggest that this new atmospherically relevant oxidation route is important relative to oxidation by the hydroxyl radical, at least at moderate concentrations of that radical. We also find that the oxidation chemistry of this compound seems to be tightly linked to the presence of alkenes of biogenic origin. 15. Atmospheric oxidation capacity sustained by a tropical forest. Science.gov (United States) Lelieveld, J; Butler, T M; Crowley, J N; Dillon, T J; Fischer, H; Ganzeveld, L; Harder, H; Lawrence, M G; Martinez, M; Taraborrelli, D; Williams, J 2008-04-10 Terrestrial vegetation, especially tropical rain forest, releases vast quantities of volatile organic compounds (VOCs) to the atmosphere, which are removed by oxidation reactions and deposition of reaction products. The oxidation is mainly initiated by hydroxyl radicals (OH), primarily formed through the photodissociation of ozone. Previously it was thought that, in unpolluted air, biogenic VOCs deplete OH and reduce the atmospheric oxidation capacity. Conversely, in polluted air VOC oxidation leads to noxious oxidant build-up by the catalytic action of nitrogen oxides (NO(x) = NO + NO2). Here we report aircraft measurements of atmospheric trace gases performed over the pristine Amazon forest. Our data reveal unexpectedly high OH concentrations. We propose that natural VOC oxidation, notably of isoprene, recycles OH efficiently in low-NO(x) air through reactions of organic peroxy radicals. Computations with an atmospheric chemistry model and the results of laboratory experiments suggest that an OH recycling efficiency of 40-80 per cent in isoprene oxidation may be able to explain the high OH levels we observed in the field. Although further laboratory studies are necessary to explore the chemical mechanism responsible for OH recycling in more detail, our results demonstrate that the biosphere maintains a remarkable balance with the atmospheric environment. 16. Utilization of a By-product Produced from Oxidative Desulfurization Process over Cs-Mesoporous Silica Catalysts Energy Technology Data Exchange (ETDEWEB) Kim, Hyeonjoo; Jeong, Kwang Eun; Jeong, Soon-Yong; Park, Young-Kwon; Kim, Do Heui; Jeon, Jong Ki 2011-02-28 We investigated the use of Cs-mesoporous silica catalysts to upgrade a by-product of oxidative desulfurization (ODS). Cs-mesoporous silica catalysts were chaeacterized through N2 adsorption, XRD, CO2-temperature-programmed desorption, and XRF. Cs-mesoporous silica prepared by the direct incorporation method showed higher catalytic performance than a Cs/MCM-41 catalyst by impregnation method for the catalytic decomposition of sulfone compounds produced from ODS process. 17. Utilization of a by-product produced from oxidative desulfurization process over Cs-mesoporous silica catalysts. Science.gov (United States) Kim, Hyeonjoo; Jeong, Kwang-Eun; Jeong, Soon-Yong; Park, Young-Kwon; Kim, Do Heui; Jeon, Jong-Ki 2011-02-01 We investigated the use of Cs-mesoporous silica catalysts to upgrade a by-product of oxidative desulfurization (ODS). Cs-mesoporous silica catalysts were characterized through N2 adsorption, XRD, CO2-temperature-programmed desorption, and XRF. Cs-mesoporous silica prepared by the direct incorporation method showed higher catalytic performance than a Cs/MCM-41 catalyst by impregnation method for the catalytic decomposition of sulfone compounds produced from ODS process. PMID:21456272 18. Synthesis by-products from the Wacker oxidation of safrole in methanol using rho-benzoquinone and palladium chloride. Science.gov (United States) Cox, M; Klass, G 2006-12-20 This paper reports the identification of a number of by-products, which are produced during the Wacker oxidation of safrole to 3,4-methylenedioxyphenyl-2-propanone (MDP2P) using rho-benzoquinone and palladium chloride when methanol is utilised as the solvent. Also described is the retrieval of these compounds from illicit samples from a clandestine laboratory, which was uncovered in South Australia in September 2003. 19. Atmospheric oxidation capacity sustained by a tropical forest NARCIS (Netherlands) Lelieveld, J.; Butler, T.; Crowley, J.N.; Dillon, T.J.; Fischer, H.; Ganzeveld, L.N.; Harder, H.; Lawrence, M.G.; Martinez, M.; Taraborelli, D.; Williams, J. 2008-01-01 Terrestrial vegetation, especially tropical rain forest, releases vast quantities of volatile organic compounds (VOCs) to the atmosphere1, 2, 3, which are removed by oxidation reactions and deposition of reaction products4, 5, 6. The oxidation is mainly initiated by hydroxyl radicals (OH), primarily 20. OXIDATION BEHAVIOR OF KOVAR ALLOY IN CONTROLLED ATMOSPHERE Institute of Scientific and Technical Information of China (English) 2008-01-01 Controlled oxidation experiments were performed on Kovar alloy by changing oxi-dation atmosphere, temperature, and exposure time to produce films with different oxide type and thickness. The results indicated that single Fe3O4 and single FeO were respectively obtained when Kovar alloy was oxidized in N2-2.31%H2O-0.95%H2 at 500℃ and in N2-2.31%H2O-O.5%H2 at 1000℃, and all kinetic curves followed linear relation; mixed oxides of FeO and Fe3O4 formed when Kovar was oxidized in N2-2.31%H2O at 1000℃, and parabolic kinetics were obeyed. Analysis of metal-lographic cross section of oxides indicated that oxygen diffusion inward through the oxide scale is responsible for intergranular oxide, which had formed beneath the oxide scales when the oxide products were mixed oxides of FeO and Fe3O4, and which did not occur when the oxide was single FeO or Fe3O4. The oxidation model was also established. 1. Formation of halogenated disinfection by-products in cobalt-catalyzed peroxymonosulfate oxidation processes in the presence of halides. Science.gov (United States) Xie, Weiping; Dong, Wei; Kong, Deyang; Ji, Yuefei; Lu, Junhe; Yin, Xiaoming 2016-07-01 Sulfate radicals (SO4(-)) generated by activation of peroxymonosulfate (PMS) and persulfate (PS) are highly oxidative and applied to degrade various organic pollutants. This research was designed to investigate formation of halogenated by-products in Co(2+) activated PMS process in the presence of halides and natural organic matter (NOM). It was revealed that no halogenated by-products were detected in the presence of Cl(-) while 189 μg/L bromoform and 100.7 μg/L dibromoacetic acid (DBAA) were found after 120 h when 2 mg/L NOM, 0.1 mM Br(-), 1.0 mM PMS, and 5 μL Co(2+) were present initially. These products are known as disinfection by-products (DBPs) since they are formed in water disinfection processes. Formation of DBPs was even more significant in the absence of Co(2+). The data indicate that both PMS and SO4(-) can transform Br(-) to reactive bromine species which react with NOM to form halogenated by-products. Less DBP formation in Co(2+)-PMS systems was due to the further destruction of DBPs by SO4(-). More DBPs species including chlorinated ones were detected in the presence of both Cl(-) and Br(-). However, more brominated species produced than chlorinate ones generally. The total DBP yield decreased with the increase of Cl(-) content when total halides kept constant. This is one of the few studies that demonstrate the formation of halogenated DBPs in Co(2+)/PMS reaction systems, which should be taken into consideration in the application of SO4(-) based oxidation technologies. PMID:27093695 2. Heterogeneous Photocatalytic Oxidation of Atmospheric Trace Contaminants Science.gov (United States) Ollis, David F. 1996-01-01 Heterogeneous photocatalysis involves the use of a light-activated catalyst at room temperature in order to carry out a desired reaction. In the presence of molecular oxygen, illumination of the n-type semiconductor oxide titanium dioxide (TiO2) provides for production of highly active forms of oxygen, such as hydroxyl radicals, which are able to carry out the complete oxidative destruction of simple hydrocarbons such as methane, ethane, ethylene, propylene, and carbon monoxide. This broad oxidation potential, coupled with the ability with sufficient residence time to achieve complete oxidation of simple hydrocarbon contaminants to carbon dioxide and water, indicated that heterogeneous photocatalysis should be examined for its potential for purification of spacecraft air. If a successful catalyst and photoreactor could be demonstrated at the laboratory level, such results would allow consideration of photocatalysts as a partial or complete replacement of adsorption systems, thereby allowing for reduction in lift-off weight of a portion of the life support system for the spacecraft, or other related application such as a space station or a conventional commercial aircraft. The present research was undertaken to explore this potential through achievement of the following plan of work: (a) ascertain the intrinsic kinetics of conversion of pollutants of interest in spacecraft, (b) ascertain the expected lifetime of catalysts through examination of most likely routes of catalyst deactivation and regeneration (c) model and explore experimentally the low pressure drop catalytic monolith, a commercial configuration for automotive exhaust control (d) examine the kinetics of multicomponent conversions. In the recent course of this work, we have also discovered how to increase catalyst activity via halide promotion which has allowed us to achieve approximately 100% conversion of an aromatic contaminant (toluene) in a very short residence time of 5-6 milliseconds. 3. Control of disinfection by-product formation using ozone-based advanced oxidation processes. Science.gov (United States) Chen, Kuan-Chung; Wang, Yu-Hsiang 2012-01-01 The effects of ozone dosage, water temperature and catalyst addition in an ozonation-fluidized bed reactor (O3/FBR) on treated water quality and on the control of chlorinated and ozonated disinfection by-products (DBPs) were investigated. A biofiltration column was used to evaluate its removal efficiency on biodegradable organic matter and to reduce DBP formation. The Dong-Gang River, polluted by agricultural and domestic wastewater in Pingtung, Taiwan, was used as the water source. The treated water quality in terms of dissolved organic carbon (DOC), biodegradable DOC, ultraviolet absorbance at 254 nm (UV254) and specific UV absorbance (SUVA) improved with increasing ozone and catalyst dosages. Catalytic ozonation was more effective than ozonation alone at reducing the formation of DBPs at a given dosage. Experimental results show that water temperature had little effect on the treated water quality with the O3/FBR system used in this study (p > 0.05). The combination of O3/FBR and the biofiltration process effectively decreased the amount ofDBP precursors. The concentration of total trihalomethanes (TTHMs) was less than the maximum contaminant level (MCL) requirement, which is 80 microg/L, for all treated waters and the concentration of five haloacetic acids (HAA5) fell below 60 microg/L with an ozone dosage higher than 2.5 mg/L. 4. Cobalt catalyzed peroxymonosulfate oxidation of tetrabromobisphenol A: Kinetics, reaction pathways, and formation of brominated by-products. Science.gov (United States) Ji, Yuefei; Kong, Deyang; Lu, Junhe; Jin, Hao; Kang, Fuxing; Yin, Xiaoming; Zhou, Quansuo 2016-08-01 Degradation of tetrabromobisphenol A (TBBPA), a flame retardant widely spread in the environment, in Co(II) catalyzed peroxymonosulfate (PMS) oxidation process was systematically explored. The second-order-rate constant for reaction of sulfate radical (SO4(-)) with TBBPA was determined to be 5.27×10(10)M(-1)s(-1). Apparently, degradation of TBBPA showed first-order kinetics to the concentrations of both Co(II) and PMS. The presence of humic acid (HA) and bicarbonate inhibited TBBPA degradation, most likely due to their competition for SO4(-). Degradation of TBBPA was initiated by an electron abstraction from one of the phenolic rings. Detailed transformation pathways were proposed, including β-scission of isopropyl bridge, phenolic ring oxidation, debromination and coupling reactions. Further oxidative degradation of intermediates in Co(II)/PMS process yielded brominated disinfection by-products (Br-DBPs) such as bromoform and brominated acetic acids. Evolution profile of Br-DBPs showed an initially increasing and then decreasing pattern with maximum concentrations occurring around 6-10h. The presence of HA enhanced the formation of Br-DBPs significantly. These findings reveal potentially important, but previously unrecognized, formation of Br-DBPs during sulfate radical-based oxidation of bromide-containing organic compounds that may pose toxicological risks to human health. PMID:27107323 5. The oxidation and surface speciation of indium and indium oxides exposed to atmospheric oxidants Science.gov (United States) Detweiler, Zachary M.; Wulfsberg, Steven M.; Frith, Matthew G.; Bocarsly, Andrew B.; Bernasek, Steven L. 2016-06-01 Metallic indium and its oxides are useful in electronics applications, in transparent conducting electrodes, as well as in electrocatalytic applications. In order to understand more fully the speciation of the indium and oxygen composition of the indium surface exposed to atmospheric oxidants, XPS, HREELS, and TPD were used to study the indium surface exposed to water, oxygen, and carbon dioxide. Clean In and authentic samples of In2O3 and In(OH)3 were examined with XPS to provide standard spectra. Indium was exposed to O2 and H2O, and the ratio of O2 - to OH- in the O1s XPS region was used to monitor oxidation and speciation of the surface. HREELS and TPD indicate that water dissociates on the indium surface even at low temperature, and that In2O3 forms at higher temperatures. Initially, OH- is the major species at the surface. Pure In2O3 is also OH- terminated following water exposure. Ambient pressure XPS studies of water exposure to these surfaces suggest that high water pressures tend to passivate the surface, inhibiting extensive oxide formation. 6. The Mantle-Atmosphere Connection: Oxidation of the Atmosphere through Mantle Convection Science.gov (United States) Lee, K. K. M.; Gu, T.; Li, M.; McCammon, C. A. 2015-12-01 Earth's mantle connects the surface with the deep interior through convection, and the evolution of its redox state will affect the distribution of siderophile elements1, recycling of refractory isotopes2 and the oxidation state of the atmosphere through volcanic outgassing3. The rise of oxygen in atmosphere, i.e., the Great Oxidation Event (G.O.E.) occurred ~2.4 billion years ago (Ga)4. However, multiple lines of evidence point to biological oxygen production well before 2.4 Ga5; while chromium isotopes in iron formations indicates a decline of atmospheric oxygen about 1.88 Ga6. In contrast to the fluctuation of atmospheric oxygen, vanadium in Archean mantle lithosphere suggests that the mantle redox state has been constant for ~3.5 Ga7. Indeed, the redox state of the deep Earth's interior is not well constrained8 and its effect on mantle dynamics is unknown. Here we show a redox-induced density difference affects mantle convection and may potentially cause the oxidation of the upper mantle. From two synthetic enstatite chondritic samples with identical bulk compositions but formed under different oxygen fugacities (fO2) compressed to lower mantle pressures and temperatures, we find Al2O3 forms its own phase separate from the dominant Mg-silicate perovskite phase (i.e., bridgmanite9) in the more reduced composition, in contrast to a more Al-rich, bridgmanite-dominated assemblage for a more oxidized starting composition. As a result, the reduced material is ~1-1.5% denser than the oxidized material. Geodynamical numerical simulations show that the redox-induced density difference could lead to an increased oxidation of Earth's upper mantle but is buffered by slow mixing with more reduced material through hot upwellings, which will potentially affect mantle redox and rise of oxygen in atmosphere. 7. UV-based advanced oxidation processes for the treatment of odour compounds: efficiency and by-product formation. Science.gov (United States) Zoschke, Kristin; Dietrich, Norman; Börnick, Hilmar; Worch, Eckhard 2012-10-15 The occurrence of the taste and odour compounds geosmin and 2-methyl isoborneol (2-MIB) affects the organoleptic quality of raw waters from drinking water reservoirs worldwide. UV-based oxidation processes for the removal of these substances are an alternative to adsorption and biological processes, since they additionally provide disinfection of the raw water. We could show that the concentration of geosmin and 2-MIB could be reduced by VUV irradiation and the combination of UV irradiation with ozone and hydrogen peroxide in pure water and water from a drinking water reservoir. The figure of merit EE/O is an appropriate tool to compare the AOPs and showed that VUV and UV/O(3) yielded the lowest treatment costs for the odour compounds in pure and raw water, respectively. Additionally, VUV irradiation with addition of ozone, generated by the VUV lamp, was evaluated. The generation of ozone and the irradiation were performed in a single reactor system using the same low-pressure mercury lamp, thereby reducing the energy consumption of the treatment process. The formation of the undesired by-products nitrite and bromate was investigated. The combination of VUV irradiation with ozone produced by a VUV lamp avoided the formation of relevant concentrations of the by-products. The internal generation of ozone is capable to produce ozone concentrations sufficient to reduce EE/O below 1 kWh m(-3) and without the risk of the formation of nitrite or bromate above the maximum contaminant level. 8. Removal of precursors for disinfection by-products (Dbps)--differences between ozone- and OH-radical-induced oxidation. Science.gov (United States) Kleiser, G; Frimmel, F H 2000-06-22 Pre-oxidation is often applied to reduce the formation of disinfection by-products (DBPs). The aim of pre-oxidation is to remove the centers of natural organic matter (NOM) which are responsible for the formation of DBPs. In this paper, the differences between ozone- and OH-radical-induced oxidation to remove DBP-precursors are compared. The experiments were done with water of the River Ruhr (Germany) with a concentration of dissolved organic carbon (DOC) of 2 mg/l. Ozonation was able to remove DBP precursors selectively. After application of an absorbed ozone mass of 1.5 mg/mg DOC, a reduction in the formation potential for (THM-FP) and in the formation potential for organic halogen adsorbable on activated carbon (AOX-FP) down to 68 and 73% of the initial concentration was achieved, respectively. A removal of NOM was not achieved using absorbed ozone masses between 0.5 and 1.5 mg/mg DOC. In the hydrogen peroxide/UV process, in which OH-radicals are the reactive species, an increase in the THM concentration was measured after application of this process with short irradiation times. The maximum value of the THM-FP was 20% higher than the initial THM-FP. After an irradiation time of 1,050 min and a hydrogen peroxide consumption of 5.6 mg/l, the THM-FP and AOX-FP decreased to 75 and 71% of the initial formation potential, respectively. There was no selective removal of DBP precursors because the DOC concentration decreased also to 75% of the initial DOC-concentration after 1,050 min of irradiation. 9. Oxidative stability during storage of fish oil from filleting by-products of rainbow trout (Oncorhynchus mykiss) is largely independent of the processing and production temperature DEFF Research Database (Denmark) Honold, Philipp; Nouard, Marie-Louise; Jacobsen, Charlotte 2016-01-01 be used to produce high quality fish oil. In this study, the oxidative stability of fish oil produced from filleting by-products was evaluated. The oil was produced from conventional or organic fish (low and high omega-3 fatty acid content) at different temperatures (70 and 90°C). The oxidative stability... 10. Catalytic oxidation of CS2 over atmospheric particles and oxide catalysts Institute of Scientific and Technical Information of China (English) 2001-01-01 The catalytic oxidization of CS2 over atmospheric particles and some oxide catalysts was explored through FT-IR, MS and a fixed-bed stainless steel reactor. The results show that at mospheric particles and some oxide catalysts exhibited considerable oxidizing activities for CS2 at ambient temperature. The reaction products are mainly COS and elemental sulfur, even CO2 on some catalysts. Among the catalysts, CaO has the strongest catalytic activity for oxidizing CS2. Fe2O3 is weaker than CaO. The catalytic activity for AI2O3 reduces considerably compared with the former two catalysts, and SiO2 the weakest. Atmospheric particle samples' catalytic activity is be tween Fe2O3's and AI2O3's. The atmospheric particle sample collected mainly consists of Ca(AI2Si2O8)· 4H2O, which is also the main component of cement. COS, the main product, is formed by the catalytic oxidization of CS2 with adsorbed “molecular” oxygen over the catalysts' surfaces. The concentration of adsorbed oxygen over catalysts' surfaces may be the key factor contributed to the oxidizing activity. It is indicated that CS2 could be catalytically oxidized over at mospheric particles, which induced that this reaction may be another important source of atmos pheric COS from CS2. 11. Metal catalyzed atmospheric oxidation reactions. A challenge to coordination chemists Energy Technology Data Exchange (ETDEWEB) Coichev, N. (Sao Paulo Univ., SP (Brazil). Inst. de Quimica); Van Eldik, R. (Universitaet Witten/Herdecke (Germany)) 1994-01-01 Oxidation reactions of SO[sub x] and NO[sub y] species in the aqueous phase can play an important role in atmospheric chemistry and are of major environmental concern. The auto-oxidation processes are known to be catalyzed by trace metal ions and complexes. An overview of the most important reactions in metal catalyzed autoxidation processes is presented. Attention is given to the oxidation of the SO[sub x] and NO[sub y] species separately, as well as to the combined chemistry that results from the interaction of SO[sub x] and NO[sub y] species in the absence and presence of metal ions. Our work has revealed a fascinating redox cycling of the metal ions and complexes during such autoxidation processes, which has turned out to present quite a challenge to coordination chemists. (authors). 118 refs., 4 figs., 1 tab. 12. Co-Mg-Al oxides issued of hydrotalcite precursors for total oxidation of volatile organic compounds. Identification and toxicological impact of the by-products Energy Technology Data Exchange (ETDEWEB) Gennequin, C.; Kouassi, S.; Tidahy, L.; Cousin, R.; Lamonier, J.F.; Garcon, G.; Shirali, P.; Cazier, F.; Aboukais, A.; Siffert, St. [Universite Lille Nord de France, 59 - Lille (France); Gennequin, C.; Kouassi, S.; Tidahy, L.; Cousin, R.; Lamonier, J.F.; Garcon, G.; Shirali, P.; Aboukais, A.; Siffert, St. [ULCO, UCEIV, MREI, 59 - Dunkerque (France); Cazier, F. [ULCO, CCM, MREI, 59 - Dunkerque (France) 2010-05-15 Catalysts based on Co-Mg-Al, which were used for the total oxidation of toluene, were synthesized by using the hydrotalcite pathway. The calcination allowed us to obtain various mixed oxide types (i.e. Co{sub 3}O{sub 4}, Co{sub 2}AlO{sub 4} or CoAl{sub 2}O{sub 4}), presenting meso-pores of about 8 nm and high specific surface areas. The solids were tested for the total oxidation of toluene and showed a total selectivity in CO{sub 2} and H{sub 2}O for 100% of toluene conversion. However, studies using diffuse reflectance infrared 'operando' and GC-MS allowed us to identify intermediary by-products stemming from the catalytic oxidation of toluene: benzene and small quantities of benzaldehyde, styrene and acetophenone. In order to contribute to the improvement of the current scientific knowledge on volatile organic compound (VOC) toxicity in humans, the lung toxicity of toluene, benzene or their association was determined by using a human epithelial lung cell model (i.e. L132 cell line). VOC cytotoxicity was studied with three complementary methods: the enzymatic activity of extracellular lactate dehydrogenase (LDH), the enzymatic activity of mitochondrial dehydrogenase (mDH), and the incorporation of 5-Bromodeoxyuridine (5-BrdU). Taken together, these results showed the occurrence of adverse effects, notably reported by significant increases in LDH activity in cell culture supernatants, 24 hours after L132 cell exposure not only to toluene alone or benzene alone, but also to their association. This original approach allowed us to integrate some toxicological parameters to help the choice of new-dedicated catalysts for the oxidative conversion of VOC. (authors) 13. Co-Mg-Al oxides issued of hydrotalcite precursors for total oxidation of volatile organic compounds. Identification and toxicological impact of the by-products International Nuclear Information System (INIS) Catalysts based on Co-Mg-Al, which were used for the total oxidation of toluene, were synthesized by using the hydrotalcite pathway. The calcination allowed us to obtain various mixed oxide types (i.e. Co3O4, Co2AlO4 or CoAl2O4), presenting meso-pores of about 8 nm and high specific surface areas. The solids were tested for the total oxidation of toluene and showed a total selectivity in CO2 and H2O for 100% of toluene conversion. However, studies using diffuse reflectance infrared 'operando' and GC-MS allowed us to identify intermediary by-products stemming from the catalytic oxidation of toluene: benzene and small quantities of benzaldehyde, styrene and acetophenone. In order to contribute to the improvement of the current scientific knowledge on volatile organic compound (VOC) toxicity in humans, the lung toxicity of toluene, benzene or their association was determined by using a human epithelial lung cell model (i.e. L132 cell line). VOC cytotoxicity was studied with three complementary methods: the enzymatic activity of extracellular lactate dehydrogenase (LDH), the enzymatic activity of mitochondrial dehydrogenase (mDH), and the incorporation of 5-Bromodeoxyuridine (5-BrdU). Taken together, these results showed the occurrence of adverse effects, notably reported by significant increases in LDH activity in cell culture supernatants, 24 hours after L132 cell exposure not only to toluene alone or benzene alone, but also to their association. This original approach allowed us to integrate some toxicological parameters to help the choice of new-dedicated catalysts for the oxidative conversion of VOC. (authors) 14. Formation of iodinated disinfection by-products during oxidation of iodide-containing waters with chlorine dioxide. Science.gov (United States) Ye, Tao; Xu, Bin; Lin, Yi-Li; Hu, Chen-Yan; Lin, Lin; Zhang, Tian-Yang; Gao, Nai-Yun 2013-06-01 This study was to explore the formation of iodinated disinfection by-products (I-DBPs), including iodoform (CHI3), iodoacetic acid (IAA) and triiodoacetic acid (TIAA), when iodide-containing artificial synthesized waters and raw waters are in contact with chlorine dioxide (ClO2). Among the investigated I-DBPs, CHI3 was the major species during ClO2 oxidation in artificial synthesized waters. Impact factors were evaluated, including the concentrations of ClO2, iodide (I(-)), dissolved organic carbon (DOC) and pH. Formation of CHI3, IAA and TIAA followed an increasing and then decreasing pattern with increased ClO2 or DOC concentration. I-DBPs yield was significantly affected by solution pH. High concentrations of I-DBPs were generated under circumneutral conditions with the maximum formation at pH 8. The increase of I(-) concentration can increase I-DBPs yields, but the increment was suppressed when I(-) concentration was higher than 50 μM. When 100 μg/L I(-)and ClO2 (7.5-44.4 μM) were spiked to the raw water samples from Yangshupu and Minhang drinking water treatment plant, certain amounts of CHI3 and IAA were found under pH 7 and the concentrations were strongly correlated with ClO2 dosage and water qualities, however, no TIAA was detected. Finally, we investigated I-DBPs formation of 18 model compounds, including 4 carboxylic acids, 5 phenols and 8 amino acids, treating with ClO2 when I(-) was present. Results showed that most of these model compounds could form a considerable amount of I-DBPs, especially for propanoic acid, butanoic acid, resorcinol, hydroquinone, alanine, glutamic acid, phenylalanine and serine. 15. Can Highly Oxidized Organics Contribute to Atmospheric New Particle Formation? Science.gov (United States) Ortega, Ismael K; Donahue, Neil M; Kurtén, Theo; Kulmala, Markku; Focsa, Cristian; Vehkamäki, Hanna 2016-03-10 Highly oxidized organic molecules may play a critical role in new-particle formation within Earth's atmosphere along with sulfuric acid, which has long been considered as a key compound in this process. Here we explore the interactions of these two partners, using quantum chemistry to find the formation free energies of heterodimers and trimers as well as the fastest evaporation rates of (2,2) tetramers. We find that the heterodimers are more strongly bound than pure sulfuric acid dimers. Their stability correlates well with the oxygen to carbon ratio of the organics, their volatility, and the number of hydrogen bonds formed. Most of the stable trimers contain one sulfuric acid and two organics (1,2), whereas many (2,2) tetramers evaporate quickly, probably due to the stability of (1,2) clusters. This finding agrees with recent experimental studies that show how new-particle formation involving oxidized organics and sulfuric acid may be rate-limited by activation of (1,2) trimers, confirming the importance of this process in the atmosphere. 16. Pathways for the Oxidation of Sarin in Urban Atmospheres Energy Technology Data Exchange (ETDEWEB) Gerald E. Streit; James E. Bossert; Jeffrey S. Gaffney; Jon Reisner; Laurie A. McNair; Michael Brown; Scott Elliott 1998-11-01 Terrorists have threatened and carried out chemicalhiological agent attacks on targets in major cities. The nerve agent sarin figured prominently in one well-publicized incident. Vapors disseminating from open containers in a Tokyo subway caused thousands of casualties. High-resolution tracer transport modeling of agent dispersion is at hand and will be enhanced by data on reactions with components of the urban atmosphere. As a sample of the level of complexity currently attainable, we elaborate the mechanisms by which sarin can decompose in polluted air. A release scenario is outlined involving the passage of a gas-phase agent through a city locale in the daytime. The atmospheric chemistry database on related organophosphorus pesticides is mined for rate and product information. The hydroxyl,radical and fine-mode particles are identified as major reactants. A review of urban air chernistry/rnicrophysics generates concentration tables for major oxidant and aerosol types in both clean and dirty environments. Organic structure-reactivity relationships yield an upper limit of 10-1' cm3 molecule-' S-* for hydrogen abstraction by hydroxyl. The associated midday loss time scale could be as little as one hour. Product distributions are difficult to define but may include nontoxic organic oxygenates, inorganic phosphorus acids, sarin-like aldehydes, and nitrates preserving cholinergic capabilities. Agent molecules will contact aerosol surfaces in on the order of minutes, with hydrolysis and side-chain oxidation as likely reaction channels. 17. Study of organic pollutants oxidation by atmospheric plasma discharge Science.gov (United States) Gumuchian, Diane; Cavadias, Simeon; Duten, Xavier; Tatoulian, Michael; da Costa, Patrick; Ognier, Stephanie 2013-09-01 Ozonation is one of the usual steps in water treatment processes. However, some organic molecules (acetic acid) cannot be decomposed during ozonation. In that context, we are developing an Advanced Oxidation Process based on the use of a needle plate discharge at atmospheric pressure. The process is a reactor with a plasma discharge between a high voltage electrode and the solution in controlled atmosphere. Characterizations of the plasma obtained in different atmospheres were carried out (Optical Emission Spectroscopy, iCCD camera observations, etc). The efficiency of the process was evaluated by the percentage of degradation of the model-pollutant, measured by liquid chromatography analysis. Treatments in nitrogen lead to the formation of NOx species that decrease the efficiency of the process. Indeed, NOx lead to the consumption of actives species created. Treatments in argon are the most efficient. Two hypotheses are considered: (i) metastable argon participates to the degradation of acetic acid or to the formation of radicals (ii) discharges in argon lead to the formation of many streamers of low energy that increase the interface plasma/solution. 18. Atmospheric pressure plasma enhanced chemical vapor deposition of zinc oxide and aluminum zinc oxide International Nuclear Information System (INIS) Zinc oxide (ZnO) and aluminum-doped zinc oxide (AZO) thin films were deposited via atmospheric pressure plasma enhanced chemical vapor deposition. A second-generation precursor, bis(1,1,1,5,5,5-hexafluoro-2,4-pentanedionato)(N,N′-diethylethylenediamine) zinc, exhibited significant vapor pressure and good stability at one atmosphere where a vaporization temperature of 110 °C gave flux ∼ 7 μmol/min. Auger electron spectroscopy confirmed that addition of H2O to the carrier gas stream mitigated F contamination giving nearly 1:1 metal:oxide stoichiometries for both ZnO and AZO with little precursor-derived C contamination. ZnO and AZO thin film resistivities ranged from 14 to 28 Ω·cm for the former and 1.1 to 2.7 Ω·cm for the latter. - Highlights: • A second generation precursor was utilized for atmospheric pressure film growth. • Addition of water vapor to the carrier gas stream led to a marked reduction of ZnF2. • Carbonaceous contamination from the precursor was minimal 19. Combined atmospheric oxidant capacity and increased levels of exhaled nitric oxide Science.gov (United States) Yang, Changyuan; Li, Huichu; Chen, Renjie; Xu, Wenxi; Wang, Cuicui; Tse, Lap Ah; Zhao, Zhuohui; Kan, Haidong 2016-07-01 Nitrogen dioxide and ozone are two interrelated oxidative pollutants in the atmosphere. Few studies have evaluated the health effects of combined oxidant capacity (O x ). We investigated the short-term effects of O x on fractional exhaled nitric oxide (FeNO), a well-established biomarker for airway inflammation, in a group of chronic obstructive pulmonary disease patients. Real-time concentrations of O x were obtained by calculating directly the sum of nitrogen dioxide and ozone. Linear mixed-effect models were applied to explore the acute effects of O x on FeNO levels. Short-term exposure to Ox was significantly associated with elevated FeNO. This effect was strongest in the first 24 h after exposure, and was robust to the adjustment of PM2.5. A 10 μg m‑3 increase in 24 h average concentrations of O x was associated with 4.28% (95% confidence interval: 1.19%, 7.37%) increase in FeNO. The effect estimates were statistically significant only among males, elders, and those with body mass index ≥24 kg m‑2, a comorbidity, higher educational attainment, or moderate airflow limitation. This analysis demonstrated an independent effect of O x on respiratory inflammation, and suggested that a single metric O x might serve as a preferable indicator of atmospheric oxidative capacity in further air pollution epidemiological studies. 20. Kinetics of the oxidation of Zn foils in air atmosphere Energy Technology Data Exchange (ETDEWEB) Baca, R; Martinez, J [Centro de Investigacion de Dispositivos Semiconductores, BUAP, Puebla. C.P. 72570 (Mexico); Kryshtab, T [Departamento de Ciencias de Materiales, ESFM - IPN, Mexico D.F (Mexico); Juarez, G; Solache, H; Andraca, J; Garcia, O; Pena-Sierra, R, E-mail: rbaca02006@yahoo.com.mx 2010-02-15 The formation kinetics of ZnO thin films grown by oxidation of polycrystalline Zn foils in air atmosphere at temperatures below the melting point is reported. Previous to the oxidation process the Zn foils were polished to produce mirror-like finished surfaces. The growth rate of the ZnO films was monitored by ellipsometric measurements. The growth rate of the ZnO films under 100 nm follows a linear and parabolic behavior in accordance with previously reported studies. The thicknesses of the films strongly influence the appearance of the final produced ZnO surface. The ZnO films surfaces with thicknesses less than 100 nm resulted uniform with low rms roughness. However as the films become thicker the rms roughness increased and a uniform distribution of whiskers was observed. X-ray diffraction and photoluminescence (PL) studies were done on the ZnO films to find out their structural and optical characteristics. PL spectra on the films are composed by two main bands; a weak near-band gap in the ultraviolet region and a strong but well defined green band. A discussion is included on the origins of the observed PL spectra. 1. Global atmospheric model for mercury including oxidation by bromine atoms Directory of Open Access Journals (Sweden) C. D. Holmes 2010-12-01 Full Text Available Global models of atmospheric mercury generally assume that gas-phase OH and ozone are the main oxidants converting Hg0 to HgII and thus driving mercury deposition to ecosystems. However, thermodynamic considerations argue against the importance of these reactions. We demonstrate here the viability of atomic bromine (Br as an alternative Hg0 oxidant. We conduct a global 3-D simulation with the GEOS-Chem model assuming gas-phase Br to be the sole Hg0 oxidant (Hg + Br model and compare to the previous version of the model with OH and ozone as the sole oxidants (Hg + OH/O3 model. We specify global 3-D Br concentration fields based on our best understanding of tropospheric and stratospheric Br chemistry. In both the Hg + Br and Hg + OH/O3 models, we add an aqueous photochemical reduction of HgII in cloud to impose a tropospheric lifetime for mercury of 6.5 months against deposition, as needed to reconcile observed total gaseous mercury (TGM concentrations with current estimates of anthropogenic emissions. This added reduction would not be necessary in the Hg + Br model if we adjusted the Br oxidation kinetics downward within their range of uncertainty. We find that the Hg + Br and Hg + OH/O3 models are equally capable of reproducing the spatial distribution of TGM and its seasonal cycle at northern mid-latitudes. The Hg + Br model shows a steeper decline of TGM concentrations from the tropics to southern mid-latitudes. Only the Hg + Br model can reproduce the springtime depletion and summer rebound of TGM observed at polar sites; the snowpack component of GEOS-Chem suggests that 40% of HgII deposited to snow in the Arctic is transferred to the ocean and land reservoirs, amounting to a net deposition flux to the Arctic of 60 Mg a−1. Summertime events of depleted Hg0 at Antarctic sites due to subsidence are much better simulated by 2. Global atmospheric model for mercury including oxidation by bromine atoms Directory of Open Access Journals (Sweden) C. D. Holmes 2010-08-01 Full Text Available Global models of atmospheric mercury generally assume that OH and ozone are the main oxidants converting Hg0 to HgII and thus driving mercury deposition to ecosystems. However, thermodynamic considerations argue against the importance of these reactions. We demonstrate here the viability of atomic bromine (Br as an alternative Hg0 oxidant. We conduct a global 3-D simulation with the GEOS-Chem model assuming Br to be the sole Hg0 oxidant (Hg + Br model and compare to the previous version of the model with OH and ozone as the sole oxidants (Hg + OH/O3 model. We specify global 3-D Br concentration fields based on our best understanding of tropospheric and stratospheric Br chemistry. In both the Hg + Br and Hg + OH/O3 models, we add an aqueous photochemical reduction of HgII in cloud to impose a tropospheric lifetime for mercury of 6.5 months against deposition, as needed to reconcile observed total gaseous mercury (TGM concentrations with current estimates of anthropogenic emissions. This added reduction would not be necessary in the Hg + Br model if we adjusted the Br oxidation kinetics downward within their range of uncertainty. We find that the Hg + Br and Hg + OH/O3 models are equally capable of reproducing the spatial distribution of TGM and its seasonal cycle at northern mid-latitudes. The Hg + Br model shows a steeper decline of TGM concentrations from the tropics to southern mid-latitudes. Only the Hg + Br model can reproduce the springtime depletion and summer rebound of TGM observed at polar sites; the snowpack component of GEOS-Chem suggests that 40% of HgII deposited to snow in the Arctic is transferred to the ocean and land reservoirs, amounting to a net deposition flux of 60 Mg a−1. Summertime events of depleted Hg0 at Antarctic sites due to subsidence are much better simulated by the Hg + Br model. Model 3. Nitrous oxide and carbon dioxide emissions during initial decomposition of animal by-products applied as fertilisers to soils. NARCIS (Netherlands) Cayuela, M.L.; Velthof, G.L.; Mondini, C.; Sinicco, T.; Groenigen, van J.W. 2010-01-01 The recycling of organic wastes as soil amendments is notably promoted in sustainable agricultural systems. However, for many animal by-products approved by organic farming regulations little is known about their effects on the greenhouse gas balance of the soil, in particular on N2O emissions. In t 4. Pineapple by-product and canola oil as partial fat replacers in low-fat beef burger: Effects on oxidative stability, cholesterol content and fatty acid profile. Science.gov (United States) Selani, Miriam M; Shirado, Giovanna A N; Margiotta, Gregório B; Rasera, Mariana L; Marabesi, Amanda C; Piedade, Sonia M S; Contreras-Castillo, Carmen J; Canniatti-Brazaca, Solange G 2016-05-01 The effect of freeze-dried pineapple by-product and canola oil as fat replacers on the oxidative stability, cholesterol content and fatty acid profile of low-fat beef burgers was evaluated. Five treatments were performed: conventional (CN, 20% fat) and four low-fat formulations (10% fat): control (CT), pineapple by-product (PA), canola oil (CO), and pineapple by-product and canola oil (PC). Low-fat cooked burgers showed a mean cholesterol content reduction of 9.15% compared to the CN. Canola oil addition improved the fatty acid profile of the burgers, with increase in the polyunsaturated/saturated fatty acids ratio and decrease in the n-6/n-3 ratio, in the atherogenic and thrombogenic indexes. The oxidative stability of the burgers was affected by the vegetable oil addition. However, at the end of the storage time (120 days), malonaldehyde values of CO and PC were lower than the threshold for the consumer's acceptance. Canola oil, in combination with pineapple by-product, can be considered promising fat replacers in the development of healthier burgers. 5. A spectroscopic study of ethylene destruction and by-product generation using a three-stage atmospheric packed-bed plasma reactor Energy Technology Data Exchange (ETDEWEB) Huebner, M.; Roepcke, J. [INP Greifswald, Felix-Hausdorff-Str. 2, 17489 Greifswald (Germany); Guaitella, O.; Rousseau, A. [LPP, Ecole Polytechnique, UPMC, Universite Paris Sud-11, CNRS, Palaiseau (France) 2013-07-21 Using a three-stage dielectric packed-bed plasma reactor at atmospheric pressure, the destruction of ethylene, a typical volatile organic compound, and the generation of major by-products have been studied by means of Fourier Transform Infrared Spectroscopy. A test gas mixture air at a gas flow of 1 slm containing 0.12% humidity with 0.1% ethylene has been used. In addition to the fragmentation of the precursor gas, the evolution of the concentration of ten stable reaction products, CO, CO{sub 2}, O{sub 3}, NO{sub 2}, N{sub 2}O, HCN, H{sub 2}O, HNO{sub 3}, CH{sub 2}O, and CH{sub 2}O{sub 2} has been monitored. The concentrations of the by-products range between 5 ppm, in the case of NO{sub 2}, and 1200 ppm, for H{sub 2}O. By the application of three sequentially working discharge cells at a frequency of f = 4 kHz and voltage values between 9 and 12 kV, a nearly complete decomposition of C{sub 2}H{sub 4} could be achieved. Furthermore, the influence of the specific energy deposition (SED) on the destruction process has been studied and the maximum value of SED was about 900 J l{sup -1}. The value of the characteristic energy {beta}, characterizing the energy efficiency of the ethylene destruction in the reactor, was found to be 330 J l{sup -1}. It was proven that the application of three reactor stages suppresses essentially the production of harmful by-products as formaldehyde, formic acid, and NO{sub 2} compared to the use of only one or two stages. Based on the multi-component detection, the carbon balance of the plasma chemical conversion of ethylene has been analyzed. The dependence of the fragmentation efficiencies of ethylene (R{sub F}(C{sub 2}H{sub 4}) = 5.5 Multiplication-Sign 10{sup 19} molecules J{sup -1}) and conversion efficiencies to the produced molecular species (R{sub C} = (0.1-3) Multiplication-Sign 10{sup 16} molecules J{sup -1}) on the discharge conditions could be estimated in the multistage plasma reactor. 6. Quantification and human health risk assessment of by-products of photo catalytic oxidation of ethylbenzene, xylene and toluene in indoor air of analytical laboratories. Science.gov (United States) Dhada, Indramani; Sharma, Mukesh; Nagar, Pavan Kumar 2016-10-01 The by-products of TiO2-based photocatalytic oxidation (PCO) of ethylbenze, p,m-xylene, o-xylene and toluene (EXT) in vapour phase and those adsorbed on the catalyst surface (solid phase) were identified and quantified on GC/GC-MS. A factor was developed in terms of μg of by-product produced per mg of EXT removed per sq-meter surface area of catalyst for estimating the mass of by-products produced. The by-products quantified were: acetone, hexane, cyclohexane, benzene, crotonaldehyde, toulene, 1,4-benzoquinone, benzaldehyde, phenol, benzylalcohol, cresol, hydroquinone and benzoic acid. The by-products accounted for 2.3-4.2% of the total mass of EXT treated. For treating concentrations of 220μg/m(3) (ethylbenzene), 260μg/m(3) (p,m-xylene), 260μg/m(3) (o-xylene) and 320μg/m(3) (toluene), at a flow rate of 7L/min for 12h in a laboratory of volume 195m(3), the estimated cancer risks of by-products to the occupants were 1.51×10(-6), 1.06×10(-6), 4.69×10(-7), and 1.58×10(-9) respectively. The overall hazard index (HI) of the by-products for EXT was of the order 10(-4); which is much less than desired level of 1.0. The estimated risks were within the acceptable level. This study has also suggested the photocatalytic degradation pathways for EX which are through formation of toluene. PMID:27208611 7. Cl atom initiated oxidation of 1-alkenes under atmospheric conditions Science.gov (United States) Walavalkar, M.; Sharma, A.; Alwe, H. D.; Pushpa, K. K.; Dhanya, S.; Naik, P. D.; Bajaj, P. N. 2013-03-01 In view of the importance of the oxidation pathways of alkenes in the troposphere, and the significance of Cl atom as an oxidant in marine boundary layer (MBL) and polluted industrial atmosphere, the reactions of four 1-alkenes (C6-C9) with Cl atoms are investigated. The rate coefficients at 298 K are measured to be (4.0 ± 0.5), (4.4 ± 0.7), (5.5 ± 0.9) and (5.9 ± 1.7) × 10-10 cm3 molecule-1 s-1 for 1-hexene, 1-heptene, 1-octene and 1-nonene, respectively. The quoted errors include the experimental 2σ, along with the error in the reference rate coefficients. From the systematic increase in the rate coefficients with the number of carbon atoms, an approximate value for the average rate coefficient for hydrogen abstraction per CH2 group in alkenes is estimated to be (4.9 ± 0.3) × 10-11 cm3 molecule-1 s-1. Based on these rate coefficients, the contribution of Cl atom reactions towards the degradation of these molecules is found to be comparable to that of OH radical reactions, under MBL conditions. The products identified in gas phase indicate that Cl atom addition occurs mainly at the terminal carbon, leading to the formation of 1-chloro-2-ketones and 1-chloro-2-ols. The major gas phase products from the alkenyl radicals (formed by H atom abstraction) are different positional isomers of long chain enols and enones. A preference for dissociation leading to an allyl radical, resulting in aldehydes, lower by three carbon atoms, is indicated. The observed relative yields suggest that in general, the increased contribution of the reactions of Cl atoms towards degradation of 1-alkenes in NOx free air does not result in an increase in the generation of small aldehydes (carbon number < 4), including chloroethanal, as compared to that in the reaction of 1-butene. 8. Stabilization of coacervate systems by products of abiogenic oxidation of low-molecular-weight compounds using the energy of. gamma. radiation Energy Technology Data Exchange (ETDEWEB) Evreinova, T.N.; Kuzin, A.M.; Kryukova, L.M.; Kameneva, T.G.; Khrust, Yu.R. 1976-01-01 The purpose of the study was to determine the possibility of stabilization of protein-carbohydrate and protein-nucleic acid systems by products of the abiogenic oxidation of pyrocatechol, pyrogallol, and o-dianisidine using the energy of gamma radiation. The protein-nucleic acid system was produced by mixing the following reagents: histone, DNA, acetate buffer, and a solution of oxidized compounds. The protein-carbohydrate system was produced by mixing the following reagents: histone, gum arabic, acetate buffer, and a solution of oxidized compounds. Results indicated that the stabilization of coacervate systems occurs when stabilizing low-molecular-weight compounds of the type of quinones and the imino form of o-dianisidine are included in them. These compounds may be formed under the action of physical factors without the participation of enzymes. (HLW) 9. Molecular understanding of atmospheric particle formation from sulfuric acid and large oxidized organic molecules OpenAIRE Schobesberger, S.; Junninen, H.; BIANCHI, F.; Lonn, G.; M. Ehn; Lehtipalo, K.; Dommen, J; S. Ehrhart; Ortega, I.K.; A. Franchin; Nieminen, T.; Riccobono, F.; Hutterli, M.; J. Duplissy; Almeida, J 2013-01-01 The formation of nanoparticles by condensable vapors in the atmosphere influences radiative forcing and therefore climate. We explored the detailed mechanism of particle formation, in particular the role of oxidized organic molecules that arise from the oxidation of monoterpenes, a class of volatile organic compounds emitted from plants. We mimicked atmospheric conditions in a well-controlled laboratory setup and found that these oxidized organics form initial clusters directly with single su... 10. Missing SO2 oxidant in the coastal atmosphere? – Evidence from high resolution measurements of OH and atmospheric sulfur compounds Directory of Open Access Journals (Sweden) H. Berresheim 2014-01-01 Full Text Available Diurnal and seasonal variations of gaseous sulfuric acid (H2SO4 and methane sulfonic acid (MSA were measured in N.E. Atlantic air at the Mace Head atmospheric research station during the years 2010 and 2011. The measurements utilized selected ion/chemical ionization mass spectrometry (SI/CIMS with a detection limit for both compounds of 4.3 × 10 4 cm−3 at 5 min signal integration. The H2SO4 and MSA gas-phase concentrations were analysed in conjunction with the condensational sink for both compounds derived from 3 nm–10 μm (diameter aerosol size distributions. Accommodation coefficients of 1.0 for H2SO4 and 0.12 for MSA were assumed leading to estimated atmospheric lifetimes of the order of 7 min and 25 min, respectively. With the SI/CIMS instrument in OH measurement mode alternating between OH signal and background (non-OH signal evidence was obtained for the presence of one or more unknown oxidants of SO2 in addition to OH. Depending on the nature of the oxidant(s their ambient concentration may be enhanced in the CIMS inlet system by additional production. The apparent unknown SO2 oxidant was additionally confirmed by direct measurements of SO2 in conjunction with calculated H2SO4 concentrations. The calculated concentrations were consistently lower than the measured concentrations by a factor 4.8 ± 3.4 when considering the oxidation of SO2 by OH as the only source of H2SO4. Both the OH and the background signal were also observed to increase significantly during daytime aerosol nucleation events, independent of the ozone photolysis frequency, J(O1D, and were followed by peaks in both H2SO4 and MSA concentrations. This suggests a strong relation between the unknown oxidant(s, OH chemistry, and the atmospheric photo-oxidation of biogenic iodine compounds. As to the identity of the oxidant(s, we have been able to exclude ClO, BrO, IO, and OIO as possible candidates based on ab initio calculations. Stabilized Criegee intermediates (s 11. Study on influence of native oxide and corrosion products on atmospheric corrosion of pure Al International Nuclear Information System (INIS) Highlights: •Corrosion products layer is only formed in coastal atmosphere. •In coastal atmosphere, rate controlling step is diffusion process. •In rural atmosphere, rate controlling step is charge transfer process. •Pitting area increases greatly in coastal site, but slightly in rural site. -- Abstract: Effects of native oxide and corrosion products on atmospheric corrosion of aluminium in rural and coastal sites were studied by electrochemical impedance spectroscopy (EIS), open-circuit potential (OCP) and scanning electron microscope (SEM) techniques after outdoor exposure. In the rural atmosphere, only the compact, adhesive native oxide layer exists, and the rate controlling step is diffusion process, while in the coastal atmosphere, another loose, inadhesive corrosion products layer exists, and a charge transfer process controls the corrosion process. The pitting area in the coastal atmosphere increases over time more obviously than that in the rural atmosphere 12. Advances of study on atmospheric methane oxidation (consumption) in forest soil Institute of Scientific and Technical Information of China (English) WANG Chen-rui; SHI Yi; YANG Xiao-ming; WU Jie; YUE Jin 2003-01-01 Next to CO2, methane (CH4) is the second important contributor to global warming in the atmosphere and global atmospheric CH4 budget depends on both CH4 sources and sinks. Unsaturated soil is known as a unique sink for atmospheric CH4 in terrestrial ecosystem. Many comparison studies proved that forest soil had the biggest capacity of oxidizing atmospheric CH4 in various unsaturated soils. However, up to now, there is not an overall review in the aspect of atmospheric CH4 oxidation (consumption) in forest soil. This paper analyzed advances of studies on the mechanism of atmospheric CH4 oxidation, and related natural factors (Soil physical and chemical characters, temperature and moisture, ambient main greenhouse gases concentrations, tree species, and forest fire) and anthropogenic factors (forest clear-cutting and thinning, fertilization, exogenous aluminum salts and atmospheric deposition, adding biocides, and switch of forest land use) in forest soils. It was believed that CH4 consumption rate by forest soil was limited by diffusion and sensitive to changes in water status and temperature of soil. CH4 oxidation was also particularly sensitive to soil C/N, Ambient CO2, CH4 and N2O concentrations, tree species and forest fire. In most cases, anthropogenic disturbances will decrease atmospheric CH4 oxidation, thus resulting in the elevating of atmospheric CH4. Finally, the author pointed out that our knowledge of atmospheric CH4 oxidation (consumption) in forest soil was insufficient. In order to evaluate the contribution of forest soils to atmospheric CH4 oxidation and the role of forest played in the process of global environmental change, and to forecast the trends of global warming exactly, more researchers need to studies further on CH4 oxidation in various forest soils of different areas. 13. The Autistic Phenotype Exhibits a Remarkably Localized Modification of Brain Protein by Products of Free Radical-Induced Lipid Oxidation Directory of Open Access Journals (Sweden) Teresa A. Evans 2008-01-01 Full Text Available Oxidative damage has been documented in the peripheral tissues of autism patients. In this study, we sought evidence of oxidative injury in autistic brain. Carboxyethyl pyrrole (CEP and iso[4]levuglandin (iso[4]LGE2-protein adducts, that are uniquely generated through peroxidation of docosahexaenoate and arachidonate-containing lipids respectively, and heme oxygenase-1 were detected immunocytochemically in cortical brain tissues and by ELISA in blood plasma. Significant immunoreactivity toward all three of these markers of oxidative damage in the white matter and often extending well into the grey matter of axons was found in every case of autism examined. This striking threadlike pattern appears to be a hallmark of the autistic brain as it was not seen in any control brain, young or aged, used as controls for the oxidative assays. Western blot and immunoprecipitation analysis confirmed neurofilament heavy chain to be a major target of CEP-modification. In contrast, in plasma from 27 autism spectrum disorder patients and 11 age-matched healthy controls we found similar levels of plasma CEP (124.5 ± 57.9 versus 110.4 ± 30.3 pmol/mL, iso[4]LGE2 protein adducts (16.7 ± 5.8 versus 13.4 ± 3.4 nmol/mL, anti-CEP (1.2 ± 0.7 versus 1.2 ± 0.3 and anti-iso[4]LGE2 autoantibody titre (1.3 ± 1.6 versus 1.0 ± 0.9, and no differences between the ratio of NO2Tyr/Tyr (7.81 E-06 ± 3.29 E-06 versus 7.87 E-06 ± 1.62 E-06. These findings provide the first direct evidence of increased oxidative stress in the autistic brain. It seems likely that oxidative injury of proteins in the brain would be associated with neurological abnormalities and provide a cellular basis at the root of autism spectrum disorders. 14. Oxidation Products of Biogenic Emissions Contribute to Nucleation of Atmospheric Particles OpenAIRE Riccobono, F.; Schobesberger, S.; Scott, CE; Dommen, J; Ortega, IK; L. Rondo; Almeida, J; Amorim, A.; BIANCHI, F.; Breitenlechner, M.; David, A.(CERN, European Organization for Nuclear Research, Geneva, Switzerland); Downard, A.; Dunne, EM; J. Duplissy; S. Ehrhart 2014-01-01 Atmospheric new-particle formation affects climate and is one of the least understood atmospheric aerosol processes. The complexity and variability of the atmosphere has hindered elucidation of the fundamental mechanism of new-particle formation from gaseous precursors. We show, in experiments performed with the CLOUD (Cosmics Leaving Outdoor Droplets) chamber at CERN, that sulfuric acid and oxidized organic vapors at atmospheric concentrations reproduce particle nucleation rates observed in ... 15. Nitric oxide and nitrous oxide emission from Hungarian forest soils; link with atmospheric N-deposition Directory of Open Access Journals (Sweden) L. Horváth 2005-06-01 Full Text Available Studies of forest nitrogen (N budgets generally measure inputs to the atmosphere in wet and dry precipitation and outputs via hydrologic export. Although denitrification has been shown to be important in many wetland ecosystems, emission of nitrogen oxides from forest soils is an important, and often overlooked, component of an ecosystem nitrogen budget. During one year (2002-2003, emissions of nitric oxide (NO and nitrous oxide (N2O were measured from Sessile oak and Norway spruce forest soils in northeast Hungary. Accumulation in small static chambers followed by gas chromatography-mass spectrometry detection was used for the estimation of N2O emission flux. Because there are rapid chemical reactions of NO and ozone, small dynamic chambers were used for in situ NO flux measurements. Average soil emissions of NO were 1.2 and 2.1 µgNm-2h-1, and for N2O were 15 and 20 µgNm-2h-1, for spruce and oak soils, respectively. The previously determined nitrogen balance between the atmosphere and the forest ecosystem was re-calculated using these soil emission figures. The total (dry + wet atmospheric N-deposition to the soil was 1.42 and 1.59gNm-2yr-1 for spruce and oak, respectively, while the soil emissions are 0.14 and 0.20 gNm-2yr-1. Thus, about 10-13% of N compounds deposited to the soil, mostly as NH3/NH4+ and HNO3/NO3-, are transformed in the soil and emitted back to the atmosphere, mostly as a greenhouse gas (N2O. 16. Avocado by-products as inhibitors of color deterioration and lipid and protein oxidation in raw porcine patties subjected to chilled storage. Science.gov (United States) Rodríguez-Carpena, J G; Morcuende, D; Estévez, M 2011-10-01 Processing of avocados generates an important amount of by-products such as peels and seeds that are rich in bioactive substances with proven radical suppressing activities. The objective of this study was to evaluate the effectiveness of peel and seed extracts from two avocado varieties-'Hass' and 'Fuerte'-as inhibitors of lipid and protein oxidation and color deterioration of raw porcine patties during chilled storage (4 °C/15 days). Avocado extracts significantly (pHass' extracts. Patties treated with avocado extracts had significantly lower amounts of TBA-RS than control ones throughout the storage. 'Hass' avocado extracts significantly inhibited the formation of protein carbonyls in chilled patties at day 15. The present results highlight the potential usage of extracts from avocado by-products as ingredients for the production of muscle foods with enhanced quality traits. 17. Ozone oxidation of antidepressants in wastewater –Treatment evaluation and characterization of new by-products by LC-QToFMS Directory of Open Access Journals (Sweden) Lajeunesse André 2013-01-01 Full Text Available Abstract Background The fate of 14 antidepressants along with their respective N-desmethyl metabolites and the anticonvulsive drug carbamazepine was examined in a primary sewage treatment plant (STP and following advanced treatments with ozone (O3. The concentrations of each pharmaceutical compound were determined in raw sewage, effluent and sewage sludge samples by LC-MS/MS analysis. The occurrence of antidepressant by-products formed in treated effluent after ozonation was also investigated. Results Current primary treatments using physical and chemical processes removed little of the compounds (mean removal efficiency: 19%. Experimental sorption coefficients (Kd of each studied compounds were also calculated. Sorption of venlafaxine, desmethylvenlafaxine, and carbamazepine on sludge was assumed to be negligible (log Kd ≤ 2, but higher sorption behavior can be expected for sertraline (log Kd ≥ 4. Ozonation treatment with O3 (5 mg/L led to a satisfactory mean removal efficiency of 88% of the compounds. Screening of the final ozone-treated effluent samples by high resolution-mass spectrometry (LC-QqToFMS did confirm the presence of related N-oxide by-products. Conclusion Effluent ozonation led to higher mean removal efficiencies than current primary treatment, and therefore represented a promising strategy for the elimination of antidepressants in urban wastewaters. However, the use of O3 produced by-products with unknown toxicity. 18. Meat composition, fatty acid profile and oxidative stability of meat from broilers supplemented with pomegranate (Punica granatum L.) by-products. Science.gov (United States) Ahmed, Sonia Tabasum; Islam, Md Manirul; Bostami, A B M Rubayet; Mun, Hong-Seok; Kim, Ye-Jin; Yang, Chul-Ju 2015-12-01 The effects of diets supplemented with four levels (0%, 0.5%, 1.0% and 2.0%) of pomegranate by-product (PB) on meat composition, fatty acid profile and oxidative stability of broiler meat were evaluated. The crude protein and moisture contents increased, whereas ether extract in breast and thigh meat and cholesterol in breast meat decreased in response to dietary PB supplementation (p<0.05). In breast and thigh meat, the sum of saturated fatty acids was lower, while the sum of mono-unsaturated and n-3 fatty acids were higher, alongside lower n-6/n-3 ratio in the 1.0% and 2.0% PB supplemented group (p<0.05). The TBARS values and pH of breast and thigh meat were reduced in the PB supplemented groups (p<0.05). Overall, the results presented herein indicate that supplementation of diets with up to 2% pomegranate by-products improved the meat composition, fatty acid profile and reduced lipid oxidation of broiler meat. PMID:26041221 19. Radioactive Fingerprinting of Microorganisms That Oxidize Atmospheric Methane in Different Soils OpenAIRE Roslev, Peter; Iversen, Niels 1999-01-01 Microorganisms that oxidize atmospheric methane in soils were characterized by radioactive labelling with 14CH4 followed by analysis of radiolabelled phospholipid ester-linked fatty acids (14C-PLFAs). The radioactive fingerprinting technique was used to compare active methanotrophs in soil samples from Greenland, Denmark, the United States, and Brazil. The 14C-PLFA fingerprints indicated that closely related methanotrophic bacteria were responsible for the oxidation of atmospheric methane in ... 20. Linking activity, composition and seasonal dynamics of atmospheric methane oxidizers in a meadow soil OpenAIRE Shrestha, Pravin Malla; KAMMANN, Claudia; Lenhart, Katharina; Dam, Bomba; Liesack, Werner 2011-01-01 Microbial oxidation is the only biological sink for atmospheric methane. We assessed seasonal changes in atmospheric methane oxidation and the underlying methanotrophic communities in grassland near Giessen (Germany), along a soil moisture gradient. Soil samples were taken from the surface layer (0–10 cm) of three sites in August 2007, November 2007, February 2008 and May 2008. The sites showed seasonal differences in hydrological parameters. Net uptake rates varied seasonally between 0 and 7... 1. The enhanced removal of carbonaceous and nitrogenous disinfection by-product precursors using integrated permanganate oxidation and powdered activated carbon adsorption pretreatment. Science.gov (United States) Chu, Wenhai; Yao, Dechang; Gao, Naiyun; Bond, Tom; Templeton, Michael R 2015-12-01 Pilot-scale tests were performed to reduce the formation of a range of carbonaceous and nitrogenous disinfection by-products (C-, N-DBPs), by removing or transforming their precursors, with an integrated permanganate oxidation and powdered activated carbon adsorption (PM-PAC) treatment process before conventional water treatment processes (coagulation-sedimentation-filtration, abbreviated as CPs). Compared with the CPs, PM-PAC significantly enhanced the removal of DOC, DON, NH3(+)-N, and algae from 52.9%, 31.6%, 71.3%, and 83.6% to 69.5%, 61.3%, 92.5%, and 97.5%, respectively. PM pre-oxidation alone and PAC pre-adsorption alone did not substantially reduce the formation of dichloroacetonitrile, trichloroacetonitrile, N-nitrosodimethylamine and dichloroacetamide. However, the PM-PAC integrated process significantly reduced the formation of both C-DBPs and N-DBPs by 60-90% for six C-DBPs and 64-93% for six N-DBPs, because PM oxidation chemically altered the molecular structures of nitrogenous organic compounds and increased the adsorption capacity of the DBP precursors, thus highlighting a synergistic effect of PM and PAC. PM-PAC integrated process is a promising drinking water technology for the reduction of a broad spectrum of C-DBPs and N-DBPs. PMID:26065622 2. Visible light photo response from N-doped anodic niobium oxide after annealing in ammonia atmosphere International Nuclear Information System (INIS) Niobium oxide films with a thickness of approximately 165 nm were prepared by electrochemical anodization. These anodic oxide layers were then treated in an ammonia atmosphere at different temperatures and durations, and characterized with XRD, XPS, ToF-SIMS and photoelectrochemical methods. Under optimized conditions nitrogen doping of the niobium oxide films takes place, resulting in a distinct photo response in the visible range of light. 3. Nitrogen atmosphere and natural antioxidants effect on muesli oxidation during long-time storage Directory of Open Access Journals (Sweden) Dorota Klensporf-Pawlik 2009-03-01 Full Text Available The effects of natural antioxidants from raspberry and black currant seeds and modified atmosphere packaging on muesli oxidative stability measured by monitoring volatile lipid oxidation products were evaluated. The effectiveness toward lipid oxidation was investigated during 10 months storage at ambient temperature. Both ethanolic extracts as well as nitrogen atmosphere influenced lipid oxidation rate in muesli measured by volatile compounds content. The most abundant lipid derived volatile compounds was hexanal. After storage, its concentration changed from 802 µg/kg to 9.8 mg/kg in muesli stored in air atmosphere, whereas in muesli stored in nitrogen atmosphere with raspberry seed extract addition it raised to 3.1 mg/kg. Although, both natural antioxidants rich in phenolic compounds, were effective towards lipid oxidation, the strongest inhibiting effect had modified atmosphere packaging. The addition of ethanolic extracts did not fortify its positive effect. Total concentration of volatile compounds in muesli after 10 months of storage was 19.6 mg/kg when stored in air and 13.7 and 11.8 mg/kg when stored with raspberry and black currant seeds extract addition respectively, while 9.8 mg/kg when stored in nitrogen atmosphere without antioxidants, and 9.7 and 9.9 mg/kg when stored with antioxidants mentioned above. 4. Five pesticides decreased oxidation of atmospheric methane in a forest soil DEFF Research Database (Denmark) Priemé, Anders; Ekelund, Flemming 2001-01-01 We found that five tested pesticides (the insecticide Dimethoat 40 EC, the herbicide Tolkan, and the fungicides Tilt 250 EC, Tilt Top, and Corbel) decreased the oxidation of atmospheric methane in slurries from a Danish forest soil. Dimethoat 40 EC was the most toxic with an EC50 value (i...... the oxidation of atmospheric methane at concentrations expected in natural soil after application of the pesticides. Pesticides, therefore, may be partly responsible for the lowered methane oxidation rates in arable soils compared to forest soils.... 5. Insights into hydroxyl measurements and atmospheric oxidation in a California forest Directory of Open Access Journals (Sweden) J. Mao 2012-03-01 Full Text Available The understanding of oxidation in forest atmospheres is being challenged by measurements of unexpectedly large amounts of hydroxyl (OH. A significant number of these OH measurements were made by laser-induced fluorescence in low-pressure detection chambers (called Fluorescence Assay with Gas Expansion (FAGE using the Penn State Ground-based Tropospheric Hydrogen Oxides Sensor (GTHOS. We deployed a new chemical removal method to measure OH in parallel with the traditional FAGE method. The new method gives on average only 40–50% of the OH from the traditional method and this discrepancy is temperature-dependent. Evidence indicates that the new method measures atmospheric OH while the traditional method is affected by internally generated OH, possibly from oxidation of biogenic volatile organic compounds. The agreement between OH measured by this new technique and modeled OH suggests that oxidation chemistry in at least one forest atmosphere is better understood than previously thought. 6. Oxidation Products of Biogenic Emissions Contribute to Nucleation of Atmospheric Particles CERN Document Server Riccobono, Francesco; Baltensperger, Urs; Worsnop, Douglas R; Curtius, Joachim; Carslaw, Kenneth S; Wimmer, Daniela; Wex, Heike; Weingartner, Ernest; Wagner, Paul E; Vrtala, Aron; Viisanen, Yrjö; Vaattovaara, Petri; Tsagkogeorgas, Georgios; Tomé, Antonio; Stratmann, Frank; Stozhkov, Yuri; Spracklen, Dominick V; Sipilä, Mikko; Praplan, Arnaud P; Petäjä, Tuukka; Onnela, Antti; Nieminen, Tuomo; Mathot, Serge; Makhmutov, Vladimir; Lehtipalo, Katrianne; Laaksonen, Ari; Kvashin, Alexander N.; Kürten, Andreas; Kupc, Agnieszka; Keskinen, Helmi; Kajos, Maija; Junninen, Heikki; Hansel, Armin; Franchin, Alessandro; Flagan, Richard C; Ehrhart, Sebastian; Duplissy, Jonathan; Dunne, Eimear M; Downard, Andrew; David, André; Breitenlechner, Martin; Bianchi, Federico; Amorim, Antonio; Almeida, João; Rondo, Linda; Ortega, Ismael K; Dommen, Josef; Scott, Catherine E; Vrtala, Aron; Santos, Filipe D; Schallhart, Simon; Seinfeld, John H; Sipila, Mikko; Donahue, Neil M; Kirkby, Jasper; Kulmala, Markku 2014-01-01 Atmospheric new-particle formation affects climate and is one of the least understood atmospheric aerosol processes. The complexity and variability of the atmosphere has hindered elucidation of the fundamental mechanism of new-particle formation from gaseous precursors. We show, in experiments performed with the CLOUD (Cosmics Leaving Outdoor Droplets) chamber at CERN, that sulfuric acid and oxidized organic vapors at atmospheric concentrations reproduce particle nucleation rates observed in the lower atmosphere. The experiments reveal a nucleation mechanism involving the formation of clusters containing sulfuric acid and oxidized organic molecules from the very first step. Inclusion of this mechanism in a global aerosol model yields a photochemically and biologically driven seasonal cycle of particle concentrations in the continental boundary layer, in good agreement with observations. 7. High-Temperature, Dual-Atmosphere Corrosion of Solid-Oxide Fuel Cell Interconnects Science.gov (United States) Gannon, Paul; Amendola, Roberta 2012-12-01 High-temperature corrosion of ferritic stainless steel (FSS) surfaces can be accelerated and anomalous when it is simultaneously subjected to different gaseous environments, e.g., when separating fuel (hydrogen) and oxidant (air) streams, in comparison with single-atmosphere exposures, e.g., air only. This so-called "dual-atmosphere" exposure is realized in many energy-conversion systems including turbines, boilers, gasifiers, heat exchangers, and particularly in intermediate temperature (600-800°C) planar solid-oxide fuel cell (SOFC) stacks. It is generally accepted that hydrogen transport through the FSS (plate or tube) and its subsequent integration into the growing air-side surface oxide layer can promote accelerated and anomalous corrosion—relative to single-atmosphere exposure—via defect chemistry changes, such as increased cation vacancy concentrations, decreased oxygen activity, and steam formation within the growing surface oxide layers. Establishment of a continuous and dense surface oxide layer on the fuel side of the FSS can inhibit hydrogen transport and the associated effects on the air side. Minor differences in FSS composition, microstructure, and surface conditions can all have dramatic influences on dual-atmosphere corrosion behaviors. This article reviews high-temperature, dual-atmosphere corrosion phenomena and discusses implications for SOFC stacks, related applications, and future research. 8. Oxidation Behaviour of Si3N4 Materials in Air and Nitrogen Atmosphere Institute of Scientific and Technical Information of China (English) ZHANGQitu; LINGZhida 1999-01-01 Si3N4 powder and hot-pressed Si3N4 ceramics added with Al2O3 are used for investigate their oxidation behvior in air and nitrogen atmosphere(with oxygen partial pressure PO2=1-10Pa),The oxidation products of Si3N4 are examined by chemical analysi,X-ray diffraction (XRD) and XPS method,Also, thermodynamic calculation is made to analyze oxidation behavior of Si3N4.The results show that only passive oxidation will occur when Si3N4 is oxidized in air at high temperature,whereas in N2 at high temperature,the active oxidation is dominant in spite of the existence of a little passive oxidation. 9. Rapid changes in biomass burning aerosols by atmospheric oxidation OpenAIRE Vakkari, Ville; Beukes, Johan Paul; Tiitta, Petri; van Zyl, Pieter G.; Josipovic, Miroslav; Venter, Andrew D.; Jaars, Kerneels 2014-01-01 Primary and secondary aerosol particles originating from biomass burning contribute significantly to the atmospheric aerosol budget and thereby to both direct and indirect radiative forcing. Based on detailed measurements of a large number of biomass burning plumes of variable age in southern Africa, we show that the size distribution, chemical composition, single-scattering albedo, and hygroscopicity of biomass burning particles change considerably during the first 2–4 h of their... 10. Mechanistic and kinetic studies on the OH-initiated atmospheric oxidation of fluoranthene International Nuclear Information System (INIS) The atmospheric oxidation of polycyclic aromatic hydrocarbons (PAHs) can generate toxic derivatives which contribute to the carcinogenic potential of particulate organic matter. In this work, the mechanism of the OH-initiated atmospheric oxidation of fluoranthene (Flu) was investigated by using high-accuracy molecular orbital calculations. All of the possible oxidation pathways were discussed, and the theoretical results were compared with the available experimental observation. The rate constants of the crucial elementary reactions were evaluated by the Rice–Ramsperger–Kassel–Marcus (RRKM) theory. The main oxidation products are a range of ring-retaining and ring-opening chemicals containing fluoranthols, fluoranthones, fluoranthenequinones, nitro-fluoranthenes, dialdehydes and epoxides. The overall rate constant of the OH addition reaction is 1.72 × 10−11 cm3 molecule−1 s−1 at 298 K and 1 atm. The atmospheric lifetime of Flu determined by OH radicals is about 0.69 days. This work provides a comprehensive investigation of the OH-initiated oxidation of Flu and should help to clarify its atmospheric conversion. - Highlights: • We studied a comprehensive mechanism of OH-initiated oxidation of fluoranthene. • We reported the formation pathways of fluoranthone, fluoranthenequinone and epoxide. • The rate constants of the crucial elementary steps were evaluated 11. Contribution of dopants to sinterability of UO2 in reducing and oxidizing atmospheres International Nuclear Information System (INIS) The effects of dopants on sinterability of UO2 have been studied in hydrogen and CO2/CO mixture atmospheres. Ta2O5, TiO2 and Nb2O5 have been used as a sintering aid for UO2. The dopants were added as oxide powers at the level of 0.10 wt% of oxide, and in the case of the Ta2O5 and Nb2O5, a further addition was made. The dopants and UO2 powders were homogenized by attrition milling. The mixed powders were pressed with die wall lubrication and sintered in hydrogen at 1700degC for 4 hrs or in oxidizing atmosphere using controlled CO2/CO mixture at 1250degC for 5 hrs. The pellets sintered in oxidizing atmospheres were reduced in hydrogen at 1200degC for 2 hrs. In reducing atmosphere, both density and microstructure of UO2 are modified by the addition of dopant. The sintered density is increased with Ta addition up to 0.33 wt% and substantially decreased by high contents of Ta. The effects on the densification and the grain growth is apparent for the addition of 0.24 wt% niobia. For 0.1 wt% titania, the sintered density is decreased, but the grain size is increased. In oxidizing atmosphere, the effect of additives on densification occurred only a little. The grain size of Ta- and Nb-doped UO2 is decreased with increasing CO2/CO ratio, but that of Ti-doped UO2 is not changed. A large portion of second phase is observed in UO2 doped with 0.66 wt% Ta2O5 and 0.1 wt% TiO2 sintered in hydrogen atmosphere, but not observed in CO2/CO atmospheres. (author) 12. Degradation of polyethylene induced by plasma in oxidizing atmospheres International Nuclear Information System (INIS) The garbage of polyethylene is not easily degradable in normal environmental conditions . The indiscriminate use of this polymer and the enormous quantity of garbage which is generated carries a damage to the environment due to its long life as waste. The objective of this work is to study the conditions in which can be carried out the degradation of polyethylene. A form of accelerating the degradation is exposing it to plasma with reactive atmospheres. In this work a study of surface modification of polyethylene by plasmas with discharges of direct current of oxygen and nitrogen is presented. (Author) 13. OH regeneration from methacrolein oxidation investigated in the atmosphere simulation chamber SAPHIR OpenAIRE Fuchs, H; I.-H. Acir; Bohn, B.; Brauers, T.; H.-P. Dorn; R. Häseler; Hofzumahaus, A.; Holland, F.; Kaminski, M.; Li, X.; Lu, K.; A. Lutz; Nehr, S.; Rohrer, F.; Tillmann, R. 2014-01-01 Hydroxyl radicals (OH) are the most important reagent for the oxidation of trace gases in the atmosphere. OH concentrations measured during recent field campaigns in isoprene rich environments were unexpectedly large. A number of studies showed that unimolecular reactions of organic peroxy radicals (RO2) formed in the initial reaction step of isoprene with OH play an important role for the OH budget in the atmosphere at low mixing ratios of nitrogen monoxide... 14. High Temperature Corrosion of Fe-C-S Cast Irons in Oxidizing and Sulfidizing Atmospheres Institute of Scientific and Technical Information of China (English) Thuan-Dinh NGUYEN; Dong-Bok LEE 2008-01-01 The corrosion behavior of spheroidal graphite and flake graphite cast irons was studied in oxidizing and sulfidizing atmospheres between 600 and 800℃ for 50 h. The corrosion rate in the sulfidizing atmosphere was faster than that in air above 700℃, due to the formation of the Feo.975S sulfide. The corrosion rate of the spheroidal graphite cast iron was similar to that of the flake graphite cast iron. 15. Oxidation Effect on Pool Boiling Heat Transfer in Atmospheric Saturated Water Energy Technology Data Exchange (ETDEWEB) Son, Hong Hyun; Jeong, Uiju; Seo, Gwang Hyeok; Jeun, Gyoodong; Kim, Sung Joong [Hanyang Univ., Seoul (Korea, Republic of) 2014-10-15 During the hypothesized severe accidents, however, the modified nature of the oxidized outer surface of RPV may act as a significant heat transfer variable to achieve In-Vessel Retention through External Reactor Vessel Cooling (IVR-ERVC) strategy, which is the one of important mitigation strategies of severe accident to delay occurrence of critical heat flux (CHF). As well understood, the CHF is mainly affected by the two distinctive conditions classified to thermal hydraulic behavior of fluid system and surface characteristics. In this regard, a CHF test considering oxidation effect on the pool boiling heat transfer of the RPV outer surface has been proposed to evaluate realistic thermal margin of IVR-ERVC strategy. In this study, pool boiling heat transfer experiment was conducted under the condition of atmospheric saturated water. Oxidized surface characteristics were quantitatively evaluated with measurement of contact angle and roughness. In this study, oxide layer formation on the heated surface was investigated and experimentally simulated to find out its effect on the pool boiling CHF. Several SS316L substrates were oxidized in the corrosive environment under the condition of high temperature with different oxidation periods. Local pitting corrosion was observed on the heating surface in 5 days of short-term oxidation but a fully oxidized surface with somewhat uniform thickness, 1. Pool boiling heat transfer tests with the bare and oxidized heaters were conducted and major findings are summarized as follows: 1. Wettability in terms of the receding angle of the oxidized surface is enhanced regardless of the oxidation period. 2. Average roughness between the oxidized surfaces is almost the same in the range of nano-scale. 3. Effect of wettability and surface roughness on the CHF was negligible in the locally oxidized surface, which may be attributed to the presence of the disconnected porous channel. Unlike the local oxidation, fully oxidized surface shows 16. NEW CATHODE MATERIALS FOR INERT AND OXIDIZING ATMOSPHERE PLASMA APPLICATION OpenAIRE Sadek, A; Kusumoto, K.; Ushio, M; Matsuda, F. 1990-01-01 This study has been carried out to develop new cathode materials for two types of thermionic cathode. First is concerning to the tungsten electrodes for the plasma furnace and welding torches. The second one is the electrodes for air plasma cutting torch. Tungsten electrodes activated with a single and combined additives of rare earth metal oxides, such as La2O3, Y2O3 and CeO2, are produced and pared with pure and thoriated tungsten electrode conventionally used, from the point of view of ele... 17. ETCHING OF WRINKLED GRAPHENE OXIDE FILMS IN NOBLE GAS ATMOSPHERE UNDER UV IRRADIATION OpenAIRE ALEKSENSKII A.E.; VUL S.P.; DIDEIKIN A.T.; Sakharov, V. I.; SERENKOV I.T.; RABCHINSKII M.K.; AFROSIMOV V.V. 2016-01-01 We have studied the process of UV reduction of wrinkled grahpene oxide films, deposited on silicon substrate from ethanol suspension. In order to avoid destruction of graphene oxide via ozone formation from ambient air, samples were protected by argon atmosphere during UV irradiation. Using the analysis of back scattering spectra for medium energy ions, we have found that the UV irradiation mediated reduction process produced significantly decreased carbon content on the substrate surface. Th... 18. Reactivity of E-butenedial with the major atmospheric oxidants Science.gov (United States) Martín, Pilar; Cabañas, Beatriz; Colmenar, Inmaculada; Salgado, María Sagrario; Villanueva, Florentina; Tapia, Araceli 2013-05-01 The degradation reactions of E-butenedial with OH and NO3 radicals and Cl atoms were investigated using a relative rate method. The experiments were carried out at ˜298 ± 1 K and an atmospheric pressure of N2 or synthetic air as the bath gas. Three different sampling/detection methods have been used for the study with Cl, OH and NO3: (1) Solid-Phase Microextraction and Gas Chromatography with Flame Ionization Detection (SPME/GC-FID), (2) ‘in situ’ with long-path Fourier Transform Infrared Spectroscopy (FTIR), and (3) Tenax solid adsorbent and Gas Chromatography with Mass Spectrometry (Tenax/GC-MS) as the detection system. The measured rate coefficients for E-butenedial (cm3 molecule-1 s-1) are as follows: (1.35 ± 0.29) × 10-10 for the Cl atom, (3.45 ± 0.34) × 10-11 for the OH radical and (1.70 ± 0.83) × 10-15 for the NO3 radical. For the reaction of Cl and NO3 these are the first rate coefficient data to be reported and in the case of OH the literature value is confirmed. This study confirms that the chemical structure of the organic substances does not influence on the reactivity with Cl, has a significant effect for OH reactions and is very important for NO3 reactions. Calculated atmospheric lifetimes are in the order of days for Cl and NO3 reactions and hours for OH. In the case of Cl atoms, a lifetime of 20 h is estimated in the early morning hours in urban coastal air. These shorter lifetimes imply that the degradation reactions of E-butenedial are of great importance because their reaction products are secondary pollutants that are involved in processes such as the formation of photochemical smog or peroxyacyl nitrates (PANs). 19. Branching between fragmentation and functionalization pathways in the oxidation of atmospheric organics Science.gov (United States) Kroll, J. H.; Smith, J. D.; Wilson, K. R.; Worsnop, D. R.; Ahmed, M.; Leone, S. R. 2008-12-01 Oxidation reactions that affect the volatility of organics are of central importance to the chemistry of the troposphere, as they lead to the formation of secondary organic aerosol, and can change the properties or loadings of existing particulate matter via oxidative processing ("aging"). Atmospheric oxidation can decrease the vapor pressure of an organic compound by adding oxygen-containing functional groups (increasing its polarity), or increase vapor pressure by breaking carbon-carbon bonds (decreasing its molecular weight). Despite being a fundamental determinant of the changes to volatilities of atmospheric organics, the functionalization/fragmentation branching ratio is not well-constrained for large atmospheric organics, especially for highly oxidized ones. Here we present laboratory measurements of this branching ratio for the heterogeneous oxidation of particulate organics. Particles of pure squalane (a branched C30 alkane) are sent into a flow reactor and are rapidly oxidized by exposure to high levels of OH; particle size and composition are measured as a function of OH exposure using a scanning mobility particle sizer (SMPS) and high-resolution time-of-flight aerosol mass spectrometer (AMS). Oxidation reactions are found to decrease particle mass, indicating volatilization (from carbon-carbon bond breaking) and also to increase the oxygen/carbon (O/C) ratio of the particulate organics, indicating the addition of functional groups. The relative rates of these two processes allows for the determination of the branching ratio between fragmentation and functionalization. Functionalization is found to dominate the oxidation of the pure hydrocarbon, but the importance of fragmentation increases as the organics become increasingly oxidized. Fragmentation pathways appear to dominate for organics with O/C ratios above ~30%. 20. Conventional methanotrophs are responsible for atmospheric methane oxidation in paddy soils Science.gov (United States) Cai, Yuanfeng; Zheng, Yan; Bodelier, Paul L. E.; Conrad, Ralf; Jia, Zhongjun 2016-06-01 Soils serve as the biological sink of the potent greenhouse gas methane with exceptionally low concentrations of ~1.84 p.p.m.v. in the atmosphere. The as-yet-uncultivated methane-consuming bacteria have long been proposed to be responsible for this high-affinity' methane oxidation (HAMO). Here we show an emerging HAMO activity arising from conventional methanotrophs in paddy soil. HAMO activity was quickly induced during the low-affinity oxidation of high-concentration methane. Activity was lost gradually over 2 weeks, but could be repeatedly regained by flush-feeding the soil with elevated methane. The induction of HAMO activity occurred only after the rapid growth of methanotrophic populations, and a metatranscriptome-wide association study suggests that the concurrent high- and low-affinity methane oxidation was catalysed by known methanotrophs rather than by the proposed novel atmospheric methane oxidizers. These results provide evidence of atmospheric methane uptake in periodically drained ecosystems that are typically considered to be a source of atmospheric methane. 1. Low-temperature sintering process for UO2 pellets in partially-oxidative atmosphere Institute of Scientific and Technical Information of China (English) YANG Xiao-dong; GAO Jia-cheng; WANG Yong; CHANG Xin 2008-01-01 Low-temperature sintering(LTS) experiments of UO2 pellets and their results were reported. Moreover, a routine process of LTS for UO2 pellets was primarily established. Being sintered at 1 400 ℃ for 3 h in a partially-oxidative atmosphere, the relative density of the pellet can be up to around 94%. Pellets with such a high density are of benefit for following-up reduction-sintering processes. Orthogonal test indicates that the importance of factors affecting the density decreases in the sequence of partial-oxidative sintering temperature and time, reduction-sintering time and temperature, and sintering atmosphere. It is found that it is helpful to introducing a small amount of water vapor into the sintering atmosphere during the latter stage. It is believed that it is the key factor to raise the O/U ratio of original powder in order to improve the properties of the low-temperature sintered pellets. 2. Complexes and clusters of water relevant to atmospheric chemistry: H2O complexes with oxidants. Science.gov (United States) Sennikov, Petr G; Ignatov, Stanislav K; Schrems, Otto 2005-03-01 Experimental observations and data from quantum chemical calculations on complexes between water molecules and small, oxygen-containing inorganic species that play an important role as oxidants in the atmosphere (O(1D), O(3P), O2(X3sigmag), O2(b1sigmag+), O3, HO, HOO, HOOO, and H2O2) are reviewed, with emphasis on their structure, hydrogen bonding, interaction energies, thermodynamic parameters, and infrared spectra. In recent years, weakly bound complexes containing water have increasingly attracted scientific attention. Water in all its phases is a major player in the absorption of solar and terrestrial radiation. Thus, complexes between water and other atmospheric species may have a perceivable influence on the radiative balance and contribute to the greenhouse effect, even though their concentrations are low. In addition, they can play an important role in the chemistry of the Earth's atmosphere, particularly in the oxidation of trace gases. Apart from gas-phase complexes, the interactions of oxidants with ice surfaces have also received considerable advertency lately due to their importance in the chemistry of snow, ice clouds, and ice surfaces (e.g., ice shields in polar regions). In paleoclimate--respectively paleoenvironmental--studies, it is essential to understand the transfer processes from the atmosphere to the ice surface. Consequently, special attention is being paid here to the intercomparison of the properties of binary complexes and the complexes and clusters of more complicated compositions, including oxidants adsorbed on ice surfaces, where ice is considered a kind of large water cluster. Various facts concerning the chemistry of the Earth's atmosphere (concentration profiles and possible influence on radical reactions in the atmosphere) are discussed. PMID:15799459 3. Carbon oxidation state as a metric for describing the chemistry of atmospheric organic aerosol Energy Technology Data Exchange (ETDEWEB) Massachusetts Institute of Technology; Kroll, Jesse H.; Donahue, Neil M.; Jimenez, Jose L.; Kessler, Sean H.; Canagaratna, Manjula R.; Wilson, Kevin R.; Altieri, Katye E.; Mazzoleni, Lynn R.; Wozniak, Andrew S.; Bluhm, Hendrik; Mysak, Erin R.; Smith, Jared D.; Kolb, Charles E.; Worsnop, Douglas R. 2010-11-05 A detailed understanding of the sources, transformations, and fates of organic species in the environment is crucial because of the central roles that organics play in human health, biogeochemical cycles, and Earth's climate. However, such an understanding is hindered by the immense chemical complexity of environmental mixtures of organics; for example, atmospheric organic aerosol consists of at least thousands of individual compounds, all of which likely evolve chemically over their atmospheric lifetimes. Here we demonstrate the utility of describing organic aerosol (and other complex organic mixtures) in terms of average carbon oxidation state (OSC), a quantity that always increases with oxidation, and is readily measured using state-of-the-art analytical techniques. Field and laboratory measurements of OSC , using several such techniques, constrain the chemical properties of the organics and demonstrate that the formation and evolution of organic aerosol involves simultaneous changes to both carbon oxidation state and carbon number (nC). 4. Atmospheric oxidation mechanism of phenol initiated by OH radical. Science.gov (United States) Xu, Cui; Wang, Liming 2013-03-21 The gas-phase oxidation mechanism of phenol initiated by OH radical was investigated using DFT and ab initio calculations. The initiation of the reaction is dominated by OH addition to ortho-position, forming P2, which subsequently combines with O2 at the ipso-position to form P2-1-OO adduct. A concerted HO2 elimination process from P2-1-OO was found to be much faster than the common ring closure to bicyclic intermediates. The HO2 elimination process from P2-1-OO forms 2-hydroxy-3,5-cyclohexadienone (HCH) as the main product and is also responsible for the experimental fact that the rate constants for reaction between P2 and O2 are about 2 orders of magnitude higher than those between other aromatic-OH adducts and O2. It was speculated that HCH would isomerize to catechol, which is thermodynamically more stable than HCH and was the experimentally observed main product, possibly through heterogeneous processes. Reaction of P2 with NO2 proceeded by addition to form P2-n-NO2 (n = 1, 3, 5), followed by HONO elimination from P2-1/3-NO2 to form catechol. The barriers for HONO elimination and catechol formation are below the separate reactants P2 and NO2, being consistent with the experimental observation of catechol in the absence of O2, while H2O elimination from P2-1/3-NO2 to form 2-nitrophenol (2NP) is hindered by high barriers. The most likely pathway for 2NP is the reaction of phenoxy radical and NO2. 5. Regional Air Quality Model Application of the Aqueous-Phase Photo Reduction of Atmospheric Oxidized Mercury by Dicarboxylic Acids Science.gov (United States) In most ecosystems, atmospheric deposition is the primary input of mercury. The total wet deposition of mercury in atmospheric chemistry models is sensitive to parameterization of the aqueous-phase reduction of divalent oxidized mercury (Hg2+). However, most atmospheric chemistry... 6. Manganese oxide phases and morphologies: A study on calcination temperature and atmospheric dependence Directory of Open Access Journals (Sweden) Matthias Augustin 2015-01-01 Full Text Available Manganese oxides are one of the most important groups of materials in energy storage science. In order to fully leverage their application potential, precise control of their properties such as particle size, surface area and Mnx+ oxidation state is required. Here, Mn3O4 and Mn5O8 nanoparticles as well as mesoporous α-Mn2O3 particles were synthesized by calcination of Mn(II glycolate nanoparticles obtained through an economical route based on a polyol synthesis. The preparation of the different manganese oxides via one route facilitates assigning actual structure–property relationships. The oxidation process related to the different MnOx species was observed by in situ X-ray diffraction (XRD measurements showing time- and temperature-dependent phase transformations occurring during oxidation of the Mn(II glycolate precursor to α-Mn2O3 via Mn3O4 and Mn5O8 in O2 atmosphere. Detailed structural and morphological investigations using transmission electron microscopy (TEM and powder XRD revealed the dependence of the lattice constants and particle sizes of the MnOx species on the calcination temperature and the presence of an oxidizing or neutral atmosphere. Furthermore, to demonstrate the application potential of the synthesized MnOx species, we studied their catalytic activity for the oxygen reduction reaction in aprotic media. Linear sweep voltammetry revealed the best performance for the mesoporous α-Mn2O3 species. 7. High Temperature Behavior of Oxidized Mild Steel in Dry and Wet Atmospheres International Nuclear Information System (INIS) During the hot rolling process, steels develop an oxide scale on their surface. This scale can affect the mechanical properties of the rolled steel and its surface aspect. The main problem comes from the mechanical integrity of the oxide scales which could delaminate or crack, leading eventually to later oxide incrustation within the steel. The objective of the present work is to qualify the mechanical integrity of the iron oxide scales during the hot rolling process. The laboratory experiments use a four point bending test to simulate the mechanical solicitation which takes place during the rolling sequence of the steel slabs. The oxide scales grow on a mild steel at 900 .deg. C under wet or dry atmosphere and the oxidized steel is then mechanically tested at 900 .deg. C or 700 .deg. C. The high temperature four point bending tests are completed with microstructural observations and with the record of acoustic emission to follow in-situ the mechanical damages of the oxide scales. The results show the role of water vapor which promotes the scale adherence, and the role of the temperature as the oxide are more damaged at 700 .deg. C than at 900 .deg. C 8. Molecular understanding of atmospheric particle formation from sulfuric acid and large oxidized organic molecules Science.gov (United States) Schobesberger, Siegfried; Junninen, Heikki; Bianchi, Federico; Lönn, Gustaf; Ehn, Mikael; Lehtipalo, Katrianne; Dommen, Josef; Ehrhart, Sebastian; Ortega, Ismael K.; Franchin, Alessandro; Nieminen, Tuomo; Riccobono, Francesco; Hutterli, Manuel; Duplissy, Jonathan; Almeida, João; Amorim, Antonio; Breitenlechner, Martin; Downard, Andrew J.; Dunne, Eimear M.; Flagan, Richard C.; Kajos, Maija; Keskinen, Helmi; Kirkby, Jasper; Kupc, Agnieszka; Kürten, Andreas; Kurtén, Theo; Laaksonen, Ari; Mathot, Serge; Onnela, Antti; Praplan, Arnaud P.; Rondo, Linda; Santos, Filipe D.; Schallhart, Simon; Schnitzhofer, Ralf; Sipilä, Mikko; Tomé, António; Tsagkogeorgas, Georgios; Vehkamäki, Hanna; Wimmer, Daniela; Baltensperger, Urs; Carslaw, Kenneth S.; Curtius, Joachim; Hansel, Armin; Petäjä, Tuukka; Kulmala, Markku; Donahue, Neil M.; Worsnop, Douglas R. 2013-01-01 Atmospheric aerosols formed by nucleation of vapors affect radiative forcing and therefore climate. However, the underlying mechanisms of nucleation remain unclear, particularly the involvement of organic compounds. Here, we present high-resolution mass spectra of ion clusters observed during new particle formation experiments performed at the Cosmics Leaving Outdoor Droplets chamber at the European Organization for Nuclear Research. The experiments involved sulfuric acid vapor and different stabilizing species, including ammonia and dimethylamine, as well as oxidation products of pinanediol, a surrogate for organic vapors formed from monoterpenes. A striking resemblance is revealed between the mass spectra from the chamber experiments with oxidized organics and ambient data obtained during new particle formation events at the Hyytiälä boreal forest research station. We observe that large oxidized organic compounds, arising from the oxidation of monoterpenes, cluster directly with single sulfuric acid molecules and then form growing clusters of one to three sulfuric acid molecules plus one to four oxidized organics. Most of these organic compounds retain 10 carbon atoms, and some of them are remarkably highly oxidized (oxygen-to-carbon ratios up to 1.2). The average degree of oxygenation of the organic compounds decreases while the clusters are growing. Our measurements therefore connect oxidized organics directly, and in detail, with the very first steps of new particle formation and their growth between 1 and 2 nm in a controlled environment. Thus, they confirm that oxidized organics are involved in both the formation and growth of particles under ambient conditions. PMID:24101502 9. Mechanistic studies on the OH-initiated atmospheric oxidation of selected aromatic hydrocarbons Energy Technology Data Exchange (ETDEWEB) Nehr, Sascha 2012-07-01 Benzene, toluene, the xylenes, and the trimethylbenzenes are among the most abundant aromatic trace constituents of the atmosphere mainly originating from anthropogenic sources. The OH-initiated atmospheric photo-oxidation of aromatic hydrocarbons is the predominant removal process resulting in the formation of O{sub 3} and secondary organic aerosol. Therefore, aromatics are important trace constituents regarding air pollution in urban environments. Our understanding of aromatic photo-oxidation processes is far from being complete. This work presents novel approaches for the investigation of OH-initiated atmospheric degradation mechanisms of aromatic hydrocarbons. Firstly, pulsed kinetic studies were performed to investigate the prompt HO{sub 2} formation from OH+ aromatic hydrocarbon reactions under ambient conditions. For these studies, the existing OH reactivity instrument, based on the flash photolysis/laser-induced fluorescence (FP/LIF) technique, was extended to the detection of HO{sub 2} radicals. The experimental design allows for the determination of HO{sub 2} formation yields and kinetics. Results of the pulsed kinetic experiments complement previous product studies and help to reduce uncertainties regarding the primary oxidation steps. Secondly, experiments with aromatic hydrocarbons were performed under atmospheric conditions in the outdoor atmosphere simulation chamber SAPHIR (Simulation of Atmospheric PHotochemistry In a large Reaction chamber) located at Forschungszentrum Juelich. The experiments were aimed at the evaluation of up-to-date aromatic degradation schemes of the Master Chemical Mechanism (MCMv3.2). The unique combination of analytical instruments operated at SAPHIR allows for a detailed investigation of HO{sub x} and NO{sub x} budgets and for the determination of primary phenolic oxidation product yields. MCMv3.2 deficiencies were identified and most likely originate from shortcomings in the mechanistic representation of ring 10. Molecular understanding of atmospheric particle formation from sulfuric acid and large oxidized organic molecules CERN Document Server Schobesberger, Siegfried; Bianchi, Federico; Lönn, Gustaf; Ehn, Mikael; Lehtipalo, Katrianne; Dommen, Josef; Ehrhart, Sebastian; Ortega, Ismael K; Franchin, Alessandro; Nieminen, Tuomo; Riccobono, Francesco; Hutterli, Manuel; Duplissy, Jonathan; Almeida, João; Amorim, Antonio; Breitenlechner, Martin; Downard, Andrew J; Dunne, Eimear M; Flagan, Richard C; Kajos, Maija; Keskinen, Helmi; Kirkby, Jasper; Kupc, Agnieszka; Kürten, Andreas; Kurtén, Theo; Laaksonen, Ari; Mathot, Serge; Onnela, Antti; Praplan, Arnaud P; Rondo, Linda; Santos, Filipe D; Schallhart, Simon; Schnitzhofer, Ralf; Sipilä, Mikko; Tomé, António; Tsagkogeorgas, Georgios; Vehkamäki, Hanna; Wimmer, Daniela; Baltensperger, Urs; Carslaw, Kenneth S; Curtius, Joachim; Hansel, Armin; Petäjä, Tuukka; Kulmala, Markku; Donahue, Neil M; Worsnop, Douglas R 2013-01-01 Atmospheric aerosols formed by nucleation of vapors affect radiative forcing and therefore climate. However, the underlying mechanisms of nucleation remain unclear, particularly the involvement of organic compounds. Here, we present high-resolution mass spectra of ion clusters observed during new particle formation experiments performed at the Cosmics Leaving Outdoor Droplets chamber at the European Organization for Nuclear Research. The experiments involved sulfuric acid vapor and different stabilizing species, including ammonia and dimethylamine, as well as oxidation products of pinanediol, a surrogate for organic vapors formed from monoterpenes. A striking resemblance is revealed between the mass spectra from the chamber experiments with oxidized organics and ambient data obtained during new particle formation events at the Hyytiälä boreal forest research station. We observe that large oxidized organic compounds, arising from the oxidation of monoterpenes, cluster directly with single sulfuric acid molec... 11. Conventional methanotrophs are responsible for atmospheric methane oxidation in paddy soils OpenAIRE Cai, Yuanfeng; Yan, Zheng; Bodelier, P. L. E.; Conrad, R.; Jia, Zhongjun 2016-01-01 Soils serve as the biological sink of the potent greenhouse gas methane with exceptionally low concentrations of ~1.84 p.p.m.v. in the atmosphere. The as-yet-uncultivated methane-consuming bacteria have long been proposed to be responsible for this ‘high-affinity’ methane oxidation (HAMO). Here we show an emerging HAMO activity arising from conventional methanotrophs in paddy soil. HAMO activity was quickly induced during the low-affinity oxidation of high-concentration methane. Activity was ... 12. Direct measurements of nitric oxide height distribution in the middle atmosphere International Nuclear Information System (INIS) The [NO] distribution over the entire range of middle atmosphere altitudes (∼20-100 km) has been obtained in only one experiment involving measurement of solar radiation absorption in the infrared range; the measurements were performed aboard the orbital station Spacelab-1. This study presents results of the first direct rock measurements of the height distribution of nitric oxide in the range ∼30-90 km, performed by an RFI photoionization sensor 13. Monitoring atmospheric nitrous oxide background concentrations at Zhongshan Station, east Antarctica. Science.gov (United States) Ye, Wenjuan; Bian, Lingen; Wang, Can; Zhu, Renbin; Zheng, Xiangdong; Ding, Minghu 2016-09-01 At present, continuous observation data for atmospheric nitrous oxide (N2O) concentrations are still lacking, especially in east Antarctica. In this paper, nitrous oxide background concentrations were measured at Zhongshan Station (69°22'25″S, 76°22'14″E), east Antarctica during the period of 2008-2012, and their interannual and seasonal characteristics were analyzed and discussed. The mean N2O concentration was 321.9nL/L with the range of 320.5-324.8nL/L during the five years, and it has been increasing at a rate of 0.29% year(-1). Atmospheric N2O concentrations showed a strong seasonal fluctuation during these five years. The concentrations appeared to follow a downtrend from spring to autumn, and then increased in winter. Generally the highest concentrations occurred in spring. This trend was very similar to that observed at other global observation sites. The overall N2O concentration at the selected global sites showed an increasing annual trend, and the mean N2O concentration in the Northern Hemisphere was slightly higher than that in the Southern Hemisphere. Our result could be representative of atmospheric N2O background levels at the global scale. This study provided valuable data for atmospheric N2O concentrations in east Antarctica, which is important to study on the relationships between N2O emissions and climate change. PMID:27593286 14. Corrosion resistance of a steel under an oxidizing atmosphere in a fluid catalytic cracking regenerator Energy Technology Data Exchange (ETDEWEB) Caminha, Ieda [Instituto Nacional de Tecnologia (INT), Rio de Janeiro, RJ (Brazil). Lab. de Metalografia e de Dureza; Zeng, Chaoliu [Chinese Academy of Science, Shenyang (China). Inst. of Corrosion and Protection of Metals. State Key Lab. for Corrosion and Protection; Paes, Marcelo Piza [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES); Monteiro, Mauricio Jesus; Rizzo, Fernando [Pontificia Univ. Catolica do Rio de Janeiro, RJ (Brazil). Dept. de Ciencia dos Materiais e Metalurgia]. E-mail: rizzo@dcmm.puc-rio.br 2004-03-01 In the present work, the corrosion resistance of an ASTM A 387 G11 steel was evaluated under two conditions: an oxidizing atmosphere in a fluid catalytic cracking regenerator of a petroleum processing unit and a simulated atmosphere in the laboratory, at temperatures of 650 deg C and 700 deg C. The characterization of the phases present in the oxidized layer was carried out by X-ray diffraction (XRD), optical microscopy (OM) and scanning electron microscopy (SEM) with X-ray energy dispersive analysis (EDS). Severe corrosion was observed after exposure to both the real and simulated conditions, with formation of several iron oxides (Fe{sub 2}O{sub 3}, Fe{sub 3}O{sub 4} and Fe O) in the product scale layer, as well as a slight inner oxidation and sulfidation of chromium in the substrate. Internal nitridation of the silicon and the manganese was observed only in the real condition, probably related to the long-term exposure inside the regenerator. (author) 15. Waiting ages for atmospheric oxygen: A titration hourglass and the oxidation of the solid Earth. (Invited) Science.gov (United States) Catling, D. C.; Claire, M.; Zahnle, K. J. 2013-12-01 Atmospheric O2 increased from less than 1 ppm to 0.2-2% at 2.45-2.22 Ga in the Great Oxidation Event (GOE). A minority opinion is that the GOE happened close to the time when oxygenic photosynthesis originated but evidence from the concentration of redox-sensitive elements in shales and their isotopes, as well as the setting and morphology of stromatolites supports the consensus view that oxygenic photosynthesis had originated by 2.8-2.7 Ga. Models show that O2 can be consumed rapidly by reductants in the Archean so that the air can remain anoxic even after photosynthesis began pumping out O2. Why did the world ultimately shift away from this balance? What conditions were needed to oxygenate the atmosphere in addition to oxygenic photosynthesis? A general principle is that a shift to an oxic environment from a reducing one requires net export of reductant. In planetary science, for example, the oxidation of the surfaces and atmospheres of other planets or satellites is universally attributed to the escape of hydrogen to space. Hydrogen escape explains the redness of Mars, several characteristics of the atmosphere of Venus, and the presence of tenuous O2 atmospheres on Ganymede, Europa, Rhea and Dione. For the Earth's rise of oxygen, many ideas focus on a decline in mantle or seafloor reductant fluxes (driven by internal geologic evolution) to the point where these fluxes were surpassed by biogenic oxygen fluxes. But for such a shift (without a role for hydrogen escape), the surface still has to export net reductant to the mantle. Such net export depends on the ratio of subducted ferric iron versus reduced carbon during the Archean, which remains poorly constrained. Over a decade ago, we proposed that rapid escape of hydrogen to space from the pre-GOE atmosphere would have gradually oxidized the Earth's surface and crust, accompanied by falling levels of atmospheric CH4 [1]. The idea is that Earth underwent a redox titration. A point would be reached where O2 became 16. Laboratory investigations of the hydroxyl radical-initiated oxidation of atmospheric volatile organic compounds Science.gov (United States) Vimal, Deepali The hydroxyl radical (OH) is one of the most important oxidants in the atmosphere, because reaction with OH is the dominant atmospheric fate of most trace atmospheric species. OH is intimately involved in a complex non-linear photochemical pathway involving anthropogenic and biogenic emissions of volatile organic compounds (VOCs) and nitrogen oxides that are emitted from vehicular exhaust and industrial emissions. This chemistry generates secondary tropospheric ozone which is an important greenhouse gas as well as a component of photochemical smog. In addition, this chemistry leads to the formation of secondary organic aerosols in the atmosphere which have implications for public health and climate change. The focus of this dissertation is to improve our understanding of this complex chemistry by investigating the rate-limiting elementary reactions which are part of the OH-initiated oxidation of important VOCs. Experimental (discharge flow technique coupled with resonance fluorescence and laser induced fluorescence) and theoretical studies (Density Functional Theory computations) of the kinetics of three atmospheric VOCs, acetic acid, 1,3-butadiene and methyl ethyl ketone are discussed. The acetic acid and OH reaction has been thought to undergo a hydrogen-bonded complex mediated pathway instead of a direct one leading to faster rate constants at lower temperature. Our results for the experimental investigation between 263-373 K and pressures of 2-5 Torr for the gas phase reaction of acetic acid with OH confirm the complex mediated reaction mechanism and indicate that acetic acid can play an important role especially in the oxidative chemistry of upper troposphere. The 1,3-butadiene and OH reaction is thought to undergo electrophilicaddition by OH which could display a complex pressure dependence similar to isoprene and 232-butenol as noted earlier in this laboratory. However, our results for the kinetics of the reaction between 273-423 K and a pressure range of 1 17. Methyl chavicol: characterization of its biogenic emission rate, abundance, and oxidation products in the atmosphere Science.gov (United States) Bouvier-Brown, N. C.; Goldstein, A. H.; Worton, D. R.; Matross, D. M.; Gilman, J. B.; Kuster, W. C.; Welsh-Bon, D.; Warneke, C.; de Gouw, J. A.; Cahill, T. M.; Holzinger, R. 2009-03-01 We report measurements of ambient atmospheric mixing ratios for methyl chavicol and determine its biogenic emission rate. Methyl chavicol, a biogenic oxygenated aromatic compound, is abundant within and above Blodgett Forest, a ponderosa pine forest in the Sierra Nevada Mountains of California. Methyl chavicol was detected simultaneously by three in-situ instruments - a gas chromatograph with mass spectrometer detector (GC-MS), a proton transfer reaction mass spectrometer (PTR-MS), and a thermal desorption aerosol GC-MS (TAG) - and found to be abundant within and above Blodgett Forest. Methyl chavicol atmospheric mixing ratios are strongly correlated with 2-methyl-3-buten-2-ol (MBO), a light- and temperature-dependent biogenic emission from the ponderosa pine trees at Blodgett Forest. Scaling from this correlation, methyl chavicol emissions account for 4-68% of the carbon mass emitted as MBO in the daytime, depending on the season. From this relationship, we estimate a daytime basal emission rate of 0.72-10.2 μgCg-1 h-1, depending on needle age and seasonality. We also present the first observations of its oxidation products (4-methoxybenzaldehyde and 4-methyoxy benzene acetaldehyde) in the ambient atmosphere. Methyl chavicol is a major essential oil component of many plant species. This work suggests that methyl chavicol plays a significant role in the atmospheric chemistry of Blodgett Forest, and potentially other sites, and should be included explicitly in both biogenic volatile organic carbon emission and atmospheric chemistry models. 18. Nitrogen oxide air pollution: atmospheric chemistry. 1964-1978 (citations from the NTIS data base). Report for 1964-78 Energy Technology Data Exchange (ETDEWEB) Cavagnaro, D.M. 1980-10-01 Research reports on photochemical air pollution models, smog chemistry and reactivity, and SSt exhaust effects are cited in the bibliography. Auroral and upper atmospheric in chemistry, and photochemistry of naturally occurring nitrogen oxides are excluded. (Contains 247 citations) 19. Oxidation of elemental mercury in the atmosphere; Constraints imposed by global scale modelling Energy Technology Data Exchange (ETDEWEB) Bergan, Torbjoern; Rodhe, Henning [Stockholm Univ. (Sweden). Dept. of Meteorology 2000-05-01 Based on the global mercury model published by Bergan et al. (1999), we present here further results from simulations where the central theme has been to evaluate the role of ozone and the hydroxyl radical as possible gas phase oxidants for the oxidation of elemental mercury in the atmosphere. The magnitude of natural and man-made mercury emissions are taken from recent literature estimates and the flux from land areas is assumed to vary by season. We consider only two mercury reservoirs, elemental mercury, Hg{sup 0}, and the more soluble divalent form, Hgll. Wet and dry deposition of Hgll is explicitly treated. Applying monthly mean fields of ozone for the oxidation of gas phase Hg{sup 0} and using the reaction rate by Hall (1995) yields a global transformation of Hg{sup 0} to Hgll which is too slow to keep the simulated concentration of Hg{sup 0} near observed values. This shows that there are additional important removal processes for Hg{sup 0} or that the reaction rate proposed by Hall (1995) is too slow. A simulation in which the oxidation rate was artificially increased, so that the global turn-over time of Hg{sup 0} was one year and the simulated average concentration of Hg{sup 0} was realistic, produced latitudinal and seasonal variations in Hg{sup 0} that did not support the hypothesis that gas phase reaction with O{sub 3} is the major oxidation process for Hg{sup 0}. Recent studies indicate that OH may be an important gas phase oxidant for Hg{sup 0}. Using OH as the oxidant and applying the preliminary oxidation rate by Sommar et al. (1999) gave an unrealistically large removal of Hg{sup 0} from the atmosphere. From calculations using a slower reaction rate, corresponding to a turn-over time of Hg{sup 0} of one year, we calculated concentrations of both Hg{sup 0} in surface air and Hgll in precipitation which correspond, both in magnitude and temporal variation, to seasonal observations in Europe and North America. This result supports the suggestion that 20. Heterogeneous Oxidation of Atmospheric Organic Aerosol: Kinetics of Changes to the Amount and Oxidation State of Particle-Phase Organic Carbon. Science.gov (United States) Kroll, Jesse H; Lim, Christopher Y; Kessler, Sean H; Wilson, Kevin R 2015-11-01 Atmospheric oxidation reactions are known to affect the chemical composition of organic aerosol (OA) particles over timescales of several days, but the details of such oxidative aging reactions are poorly understood. In this study we examine the rates and products of a key class of aging reaction, the heterogeneous oxidation of particle-phase organic species by the gas-phase hydroxyl radical (OH). We compile and reanalyze a number of previous studies from our laboratories involving the oxidation of single-component organic particles. All kinetic and product data are described on a common basis, enabling a straightforward comparison among different chemical systems and experimental conditions. Oxidation chemistry is described in terms of changes to key ensemble properties of the OA, rather than to its detailed molecular composition, focusing on two quantities in particular, the amount and the oxidation state of the particle-phase carbon. Heterogeneous oxidation increases the oxidation state of particulate carbon, with the rate of increase determined by the detailed chemical mechanism. At the same time, the amount of particle-phase carbon decreases with oxidation, due to fragmentation (C-C scission) reactions that form small, volatile products that escape to the gas phase. In contrast to the oxidation state increase, the rate of carbon loss is nearly uniform among most systems studied. Extrapolation of these results to atmospheric conditions indicates that heterogeneous oxidation can have a substantial effect on the amount and composition of atmospheric OA over timescales of several days, a prediction that is broadly in line with available measurements of OA evolution over such long timescales. In particular, 3-13% of particle-phase carbon is lost to the gas phase after one week of heterogeneous oxidation. Our results indicate that oxidative aging represents an important sink for particulate organic carbon, and more generally that fragmentation reactions play a major 1. Oxidation of a new Biogenic VOC: Chamber Studies of the Atmospheric Chemistry of Methyl Chavicol Science.gov (United States) Bloss, William; Alam, Mohammed; Adbul Raheem, Modinah; Rickard, Andrew; Hamilton, Jacqui; Pereira, Kelly; Camredon, Marie; Munoz, Amalia; Vazquez, Monica; Vera, Teresa; Rodenas, Mila 2013-04-01 The oxidation of volatile organic compounds (VOCs) leads to formation of ozone and SOA, with consequences for air quality, health, crop yields, atmospheric chemistry and radiative transfer. Recent observations have identified Methyl Chavicol ("MC": Estragole; 1-allyl-4-methoxybenzene, C10H12O) as a major BVOC above pine forests in the USA, and oil palm plantations in Malaysian Borneo. Palm oil cultivation, and hence MC emissions, may be expected to increase with societal food and bio fuel demand. We present the results of a series of simulation chamber experiments to assess the atmospheric fate of MC. Experiments were performed in the EUPHORE facility, monitoring stable product species, radical intermediates, and aerosol production and composition. We determine rate constants for reaction of MC with OH and O3, and ozonolysis radical yields. Stable product measurements (FTIR, PTRMS, GC-SPME) are used to determine the yields of stable products formed from OH- and O3- initiated oxidation, and to develop an understanding of the initial stages of the MC degradation chemistry. A surrogate mechanism approach is used to simulate MC degradation within the MCM, evaluated in terms of ozone production measured in the chamber experiments, and applied to quantify the role of MC in the real atmosphere. 2. Transparent conductive indium-doped zinc oxide films prepared by atmospheric pressure plasma jet Energy Technology Data Exchange (ETDEWEB) Chang, Kow-Ming [Department of Electronics Engineering and Institute of Electronics, National Chiao Tung University, 1001 Ta Hsueh Road, Hsinchu, Taiwan 30010 (China); College of Electrical and Information Engineering, I-Shou University, Kaohsiung County, Taiwan 84001 (China); Huang, Sung-Hung, E-mail: sunghunghuang@gmail.com [Department of Electronics Engineering and Institute of Electronics, National Chiao Tung University, 1001 Ta Hsueh Road, Hsinchu, Taiwan 30010 (China); Wu, Chin-Jyi [Industrial Technology Research Institute, Mechanical and Systems Research Laboratories, 195, Sec. 4, Chung Hsing Rd., Chutung, Hsinchu, 31040, Taiwan (China); Lin, Wei-Li; Chen, Wei-Chiang; Chi, Chia-Wei [Department of Electronics Engineering and Institute of Electronics, National Chiao Tung University, 1001 Ta Hsueh Road, Hsinchu, Taiwan 30010 (China); Lin, Je-Wei; Chang, Chia-Chiang [Industrial Technology Research Institute, Mechanical and Systems Research Laboratories, 195, Sec. 4, Chung Hsing Rd., Chutung, Hsinchu, 31040, Taiwan (China) 2011-05-31 Atmospheric-pressure plasma processing has attracted much interest for industrial applications due to its low cost, high processing speed and simple system. In this study, atmospheric-pressure plasma jet technique was developed to deposit indium-doped zinc oxide films. The inorganic metal salts of zinc nitrate and indium nitrate were used as precursors for Zn ions and In ions, respectively. The effect of different indium doping concentration on the morphological, structural, electrical and optical properties of the films was investigated. Grazing incidence X-ray diffraction results show that the deposited films with a preferred (002) orientation. The lowest resistivity of 1.8 x 10{sup -3} {Omega} cm was achieved with the 8 at.% indium-doped solution at the substrate temperature of 200 deg. C in open air, and average transmittance in the visible region was more than 80%. 3. Glass-ceramic sealant for solid oxide fuel cells application: Characterization and performance in dual atmosphere Science.gov (United States) Sabato, A. G.; Cempura, G.; Montinaro, D.; Chrysanthou, A.; Salvo, M.; Bernardo, E.; Secco, M.; Smeacetto, F. 2016-10-01 A glass-ceramic composition was designed and tested for use as a sealant in solid oxide fuel cell (SOFC) planar stack design. The crystallization behaviour was investigated by calculating the Avrami parameter (n) and the activation energy for crystallization (Ec) was obtained. The calculated values for n and Ec were 3 and 413.5 kJ/mol respectively. The results of thermal analyses indicate that this composition shows no overlap between the sintering and crystallization stages and thus an almost pore-free sealant can be deposited and sintered at 850 °C in air for 30 min. A gas tightness test has been carried out at 800 °C for 1100 h in dual atmosphere (Ar-H2 and air) without recording any leakage. Morphological and crystalline phase analyses were conducted prior and following tests in dual atmospheres in order to assess the compatibility of the proposed sealant with the metallic interconnect. 4. Oxygen dynamics in the aftermath of the Great Oxidation of Earth’s atmosphere DEFF Research Database (Denmark) Canfield, Donald Eugene; Ngombi-Pemba, Lauriss; Hammarlund, Emma; 2013-01-01 The oxygen content of Earth’s atmosphere has varied greatly through time, progressing from exceptionally low levels before about 2.3 billion years ago, to much higher levels afterward. In the absence of better information, we usually view the progress in Earth’s oxygenation as a series of steps......-oxygenated deep waters whereas the youngest were deposited in euxinic waters, which were globally extensive. These fluctuations in oxygenation were likely driven by the comings and goings of the Lomagundi carbon isotope excursion, the longest–lived positive δ13C excursion in Earth history, generating a huge...... oxygen source to the atmosphere. As the Lomagundi event waned, the oxygen source became a net oxygen sink as Lomagundi organic matter became oxidized, driving oxygen to low levels; this state may have persisted for 200 million years.... 5. Enhancement of atmospheric H2SO4/H2O nucleation: organic oxidation products versus amines Directory of Open Access Journals (Sweden) T. Berndt 2013-06-01 Full Text Available Atmospheric H2SO4/H2O nucleation influencing effects have been studied in the flow tube IfT-LFT (Institute for Tropospheric Research – Laminar Flow Tube at 293 ± 0.5 K and a pressure of 1 bar using synthetic air as the carrier gas. The presence of a possible background amine concentration in the order of 107–108 molecule cm−3 throughout the experiments has to be taken into account. In a first set of investigations, ozonolysis of olefins (tetramethylethylene, 1-methyl-cyclohexene, α-pinene and limonene for close to atmospheric concentrations, served as the source of OH radicals and possibly other oxidants initiating H2SO4 formation starting from SO2. The oxidant generation is inevitably associated with the formation of a series of organic oxidation products arising from the parent olefins. These products (first generation mainly showed no clear effect on the number of nucleated particles within a wide range of experimental conditions for H2SO4 concentrations higher than ~107 molecule cm−3. A comparison of the results of two different particle counters (50% cut-off size: about 1.5 nm or 2.5–3 nm suggested that the early growth process of the nucleated particles was not significantly influenced by the organic oxidation products. An additional, H2SO4-independent process of particle (nano-CN formation was observed in the case of α-pinene and limonene ozonolysis for H2SO4 concentrations smaller than ~10 7 molecule cm−3. Furthermore, the findings confirm the existence of an additional oxidant for SO2 beside OH radicals, very likely stabilized Criegee Intermediate (sCI. In the case of the ozonolysis of tetramethylethylene, the H2SO4 measurements in the absence and presence of an OH radical scavenger were well described by modelling using recently obtained kinetic data for the sCI reactivity in this system. A second set of experiments has been performed in the presence of added amines (trimethylamine, dimethylamine, aniline and pyridine in 6. OH regeneration from methacrolein oxidation investigated in the atmosphere simulation chamber SAPHIR Directory of Open Access Journals (Sweden) H. Fuchs 2014-02-01 Full Text Available Hydroxyl radicals (OH are the most important reagent for the oxidation of trace gases in the atmosphere. OH concentrations measured during recent field campaigns in isoprene rich environments were unexpectedly large. A number of studies showed that unimolecular reactions of organic peroxy radicals (RO2 formed in the initial reaction step of isoprene with OH play an important role for the OH budget in the atmosphere at low mixing ratios of nitrogen monoxide (NO of less than 100 pptv. It has also been suggested that similar reactions potentially play an important role for RO2 from other compounds. Here, we investigate the oxidation of methacrolein (MACR, one major oxidation product of isoprene, by OH in experiments in the simulation chamber SAPHIR under controlled atmospheric conditions. The experiments show that measured OH concentrations are approximately 50% larger than calculated by current chemical models for conditions of the experiments (NO mixing ratio of 90 pptv. The analysis of the OH budget reveals a so far unaccounted OH source, which is correlated with the production rate of RO2 radicals from MACR. In order to balance the measured OH destruction rate, (0.77±0.3 OH radicals need to be additionally reformed from each OH that has reacted with MACR. The strong correlation of the missing OH source with the production of RO2 radicals is consistent with the concept of OH formation from unimolecular isomerization and decomposition reactions of RO2. The comparison of observations with model calculations gives a lower limit of 0.03 s−1 for the reaction rate constant, if the OH source is attributed to an isomerization reaction of one RO2 species formed in the MACR+OH reaction as suggested in literature. This fast isomerization reaction would be competitive to the reaction of this RO2 species with minimum 150 pptv NO. 7. Synthesis of barium titanium oxide from barium sulphate and anatase. Study of equimolar mixtures under different atmospheres International Nuclear Information System (INIS) To enable the ceramization of a barium sulphate-rich radioactive waste the synthesis of barium titanium oxide is studied by using anatase and barium sulphate. As a function of the calcination atmosphere, helium (or air) and Ar/H2, two reactions are studied. A mechanism of barium titanium oxide synthesis in helium (or in air) is proposed 8. Complexes and Clusters of Water Relevant to Atmospheric Chemistry: H2O Complexes with Oxidants OpenAIRE Sennikov, Peter; Ignatov, Stanislav; Schrems, Otto 2005-01-01 Experimental observations and data from quantum chemical calculations related to the complexes between water molecules and small oxygen containing inorganic species which are playing an important role as oxidants (O(1D), O(3P), O2(X3Σg), O2(b1Σg+), O3, HO, HOO, HOOO, and H2O2) in the atmosphere are reviewed with emphasis on their structure, hydrogen bonding, interaction energies, thermodynamic parameters and IR spectra. In recent years, weakly bound complexes containing water have i... 9. Self-sustained carbon monoxide oxidation oscillations on size-selected platinum nanoparticles at atmospheric pressure DEFF Research Database (Denmark) Jensen, Robert; Andersen, Thomas; Nierhoff, Anders Ulrik Fregerslev; 2013-01-01 High-quality mass spectrometry data of the oscillatory behavior of CO oxidation on SiO2 supported Pt-nanoparticles at atmospheric pressure have been acquired as a function of pressure, coverage, gas composition and nanoparticle size. The oscillations are self-sustained for several days at constant......, temperature, pressure and CO/O2 ratio. The frequency of the oscillations is very well defined and increases over time. The oscillation frequency is furthermore strongly temperature dependent with increasing temperature resulting in increasing frequency. A plausible mechanism for the oscillations is proposed... 10. Ozone oxidation of antidepressants in wastewater –Treatment evaluation and characterization of new by-products by LC-QToFMS OpenAIRE Lajeunesse André; Blais Mireille; Barbeau Benoît; Sauvé Sébastien; Gagnon Christian 2013-01-01 Abstract Background The fate of 14 antidepressants along with their respective N-desmethyl metabolites and the anticonvulsive drug carbamazepine was examined in a primary sewage treatment plant (STP) and following advanced treatments with ozone (O3). The concentrations of each pharmaceutical compound were determined in raw sewage, effluent and sewage sludge samples by LC-MS/MS analysis. The occurrence of antidepressant by-products formed in treated effluent after ozonation was also investigat... 11. Heterogeneous chemistry and reaction dynamics of the atmospheric oxidants, O3, NO3, and OH, on organic surfaces. Science.gov (United States) Chapleski, Robert C; Zhang, Yafen; Troya, Diego; Morris, John R 2016-07-01 Heterogeneous chemistry of the most important atmospheric oxidants, O3, NO3, and OH, plays a central role in regulating atmospheric gas concentrations, processing aerosols, and aging materials. Recent experimental and computational studies have begun to reveal the detailed reaction mechanisms and kinetics for gas-phase O3, NO3, and OH when they impinge on organic surfaces. Through new research approaches that merge the fields of traditional surface science with atmospheric chemistry, researchers are developing an understanding for how surface structure and functionality affect interfacial chemistry with this class of highly oxidizing pollutants. Together with future research initiatives, these studies will provide a more complete description of atmospheric chemistry and help others more accurately predict the properties of aerosols, the environmental impact of interfacial oxidation, and the concentrations of tropospheric gases. 12. Atmospheric Oxidation of Squalene: Molecular Study Using COBRA Modeling and High-Resolution Mass Spectrometry Energy Technology Data Exchange (ETDEWEB) Fooshee, David R.; Aiona, Paige K.; Laskin, Alexander; Laskin, Julia; Nizkorodov, Sergey; Baldi, Pierre 2015-10-22 Squalene is a major component of skin and plant surface lipids, and is known to be present at high concentrations in indoor dust. Its high reactivity toward ozone makes it an important ozone sink and a natural protectant against atmospheric oxidizing agents. While the volatile products of squalene ozonolysis are known, the condensed-phase products have not been characterized. We present an analysis of condensed-phase products resulting from an extensive oxidation of squalene by ozone probed by electrospray ionization (ESI) high-resolution mass spectrometry (HR-MS). A complex distribution of nearly 1,300 peaks assignable to molecular formulas is observed in direct infusion positive ion mode ESI mass spectra. The distribution of peaks in the mass spectra suggests that there are extensive cross-coupling reactions between hydroxy-carbonyl products of squalene ozonolysis. To get additional insights into the mechanism, we apply a Computational Brewing Application (COBRA) to simulate the oxidation of squalene in the presence of ozone, and compare predicted results with those observed by the HR-MS experiments. The system predicts over one billion molecular structures between 0-1450 Da, which correspond to about 27,000 distinct elemental formulas. Over 83% of the squalene oxidation products inferred from the mass spectrometry data are matched by the simulation. Simulation indicates a prevalence of peroxy groups, with hydroxyl and ether groups being the second-most important O-containing functional groups formed during squalene oxidation. These highly oxidized products of squalene ozonolysis may accumulate on indoor dust and surfaces, and contribute to their redox capacity. 13. CO oxidation over ruthenium: identification of the catalytically active phases at near-atmospheric pressures Energy Technology Data Exchange (ETDEWEB) Gao, Feng; Goodman, Wayne D. 2012-05-21 CO oxidation was carried out over Ru(0001) and RuO2(110) thin film grown on Ru(0001) at various O2/CO ratios near atmospheric pressures. Reaction kinetics, coupled with in situ polarization modulation infrared reflection absorption spectroscopy (PM-IRAS) and post-reaction Auger electron spectroscopy (AES) measurements were used to identify the catalytically relevant phases at different reaction conditions. Under stoichiometric and reducing conditions at all reaction temperatures, as well as net-oxidizing reaction conditions below {approx}475 K, a reduced metallic phase with chemisorbed oxygen is the thermodynamically stable and catalytically active phase. On this surface CO oxidation occurs at surface defect sites, for example step edges. Only at net-oxidizing reaction conditions and above {approx}475 K is the RuO2 thin film grown on metallic Ru stable and active. However, RuO2 is not active itself without the existence of the metal substrate, suggesting the importance of a strong metal-substrate interaction (SMSI). 14. Synthesis of porous superparamagnetic iron oxides from colloidal nanoparticles: Effect of calcination temperature and atmosphere Energy Technology Data Exchange (ETDEWEB) Cheng, Wei; Xu, Jing; Ding, Wei; Wang, Yajie; Zheng, Wenping; Wu, Feng; Li, Jinjun, E-mail: ljjcbacademy@163.com 2015-03-01 Nanostructured iron oxides with superparamagnetism were synthesized from colloidal particles of hydrous iron oxide. The synthesis procedure involved preparation of acetone-nanoparticle composite and calcination of the composite in air or nitrogen. The effects of calcination temperature and atmosphere on the properties of the products were investigated. Powder X-ray diffraction, {sup 57}Fe Mössbauer spectra, transmission electron microscopy, nitrogen sorption, thermal analysis and vibrating-sample magnetometry were applied to characterize the materials. The products calcined in flowing air are composed of nanoparticles, while those calcined in flowing nitrogen contain nanosheets. The former has larger specific surface areas, whereas the latter has stronger saturation magnetization in external magnetic field. Increasing calcination temperature reduced the specific surface area of the product, whereas enhanced its saturation magnetization. Furthermore, the iron oxides with superparamagnetism showed good affinity to arsenite, and therefore they could be potential adsorbents for arsenic remediation in water. - Highlights: • Nanostructured superparamagnetic iron oxides were synthesized from colloidal nanoparticles. • Calcination in air led to formation of nanoparticles. • Calcination in nitrogen led to formation of nanosheets. • The superparamagnetic materials had high adsorption capabilities for arsenite. 15. Methyl chavicol: characterization of its biogenic emission rate, abundance, and oxidation products in the atmosphere Directory of Open Access Journals (Sweden) N. C. Bouvier-Brown 2008-11-01 Full Text Available We report measurements of ambient atmospheric mixing ratios for methyl chavicol and determine its biogenic emission rate. Methyl chavicol, a biogenic oxygenated aromatic compound, is abundant within and above Blodgett Forest, a ponderosa pine forest in the Sierra Nevada Mountains of California. Methyl chavicol was detected simultaneously by three in-situ instruments – a gas chromatograph with mass spectrometer detector (GC-MS, a proton transfer reaction mass spectrometer (PTR-MS, and a thermal desorption aerosol GC-MS (TAG – and found to be abundant within and above Blodgett Forest, a ponderosa pine forest in the Sierra Nevada Mountains of California. Methyl chavicol atmospheric mixing ratios are strongly correlated with 2-methyl-3-buten-2-ol (MBO, a light- and temperature-dependent biogenic emission from the ponderosa pine trees at Blodgett Forest. Scaling from this correlation, methyl chavicol emissions account for 4–68% of the carbon mass emitted as MBO in the daytime, depending on the season. From this relationship, we estimate a daytime basal emission rate of 0.72–10.2 μgCg−1h−1, depending on needle age and seasonality. We also present the first observations of its oxidation products (4-methoxybenzaldehyde and 4-methyoxy benzene acetaldehyde in the ambient atmosphere. Methyl chavicol is a major essential oil component of many plant species. This work suggests that methyl chavicol plays a significant role in the atmospheric chemistry of Blodgett Forest, and potentially other sites, and should be included explicitly in both biogenic volatile organic carbon emission and atmospheric chemistry models. 16. Magnetic Properties of Iron Oxide Minerals in Atmospheric Dust and Source Sediments from Western US Science.gov (United States) Moskowitz, B. M.; Yauk, K.; Till, J. L.; Berquo, T. S.; Banerjee, S. K.; Reynolds, R. L.; Goldstein, H. L. 2011-12-01 Atmospheric dust contains iron oxide minerals that can play important roles in various physical and biological processes affecting atmospheric and surface temperatures, marine phytoplankton productivity, and human health. Iron oxide minerals in dust deposited on mountain snow cover are especially important because these minerals absorb solar and IR radiation leading to changes in albedo and affecting the timing and rate of spring and summer snowpack melting. As part of an ongoing project to study physical and chemical properties of dust from sources to sinks in the western US, we will describe one approach to characterize iron oxide mineralogy using magnetic property measurements and Mossbauer spectroscopy. Magnetic property measurements over a wide range of temperatures (2-300 K) and magnetic fields (0-5 T) are particularly sensitive to composition, particle size (from nanometer to micrometer), and concentration of iron oxide and oxyhydroxide minerals. The high sensitivity of magnetic measurements to target minerals allows the measurement of bulk samples preventing any aliasing of composition or grain size resulting from attempts at prior magnetic separation. In addition, different magnetic measurement protocols can isolate different particle-size assemblages and different compositions in multicomponent mixtures and help to identify dust-source areas. These techniques have been applied to dust deposited on snow (DOS) cover of the San Juan Mountains, Colorado (collected 2005-2010) and Wasatch Mountains, Utah (collected 2010) and possible dust-source sediments from the North American Great Basin and Colorado Plateau deserts. Results show that all samples contain a high coercivity phase consistent with hematite and/or goethite as the dominate ferric oxide mineral plus minor amounts of magnetite (hematite concentration ( x2 difference) but with similar spreads in magnetite concentrations (0.05-0.2%) within each group. Preliminary Mössbauer spectroscopy at 300 K for 17. Photon and Water Mediated Sulfur Oxide and Acid Chemistry in the Atmosphere of Venus Science.gov (United States) Kroll, Jay A.; Vaida, Veronica 2014-06-01 Sulfur compounds have been observed in the atmospheres of a number of planetary bodies in our solar system including Venus, Earth, Mars, Io, Europa, and Callisto. The global cloud cover on Venus located at an altitude between 50 and 80 kilometers is composed primarily of sulfuric acid (H_2SO_4) and water. Planetary photochemical models have attempted to explain observations of sulfuric acid and sulfur oxides with significant discrepancies remaining between models and observation. In particular, high SO_2 mixing ratios are observed above 90 km which exceed model predictions by orders of magnitude. Work recently done in the Vaida lab has shown red light can drive photochemistry through overtone pumping for acids like H_2SO_4 and has been successful in explaining much of the sulfur chemistry in Earth's atmosphere. Water can have a number of interesting effects such as catalysis, suppression, and anti-catalysis of thermal and photochemical processes. We investigate the role of water complexes in the hydration of sulfur oxides and dehydration of sulfur acids and present spectroscopic studies to document such effects. We investigate these reactions using FTIR and UV/Vis spectroscopy and will report on our findings. 18. Carbon isotope excursions and the oxidant budget of the Ediacaran atmosphere and ocean Science.gov (United States) Bristow, Thomas F.; Kennedy, Martin J. 2008-11-01 A possible global drop in marine carbon isotope values to aslow as -12 Peedee belemnite (PDB), recorded in the EdiacaranShuram Formation of Oman, has been attributed to the non-steady-stateoxidation of oceanic dissolved organic carbon (DOC) resultingfrom the rise in atmospheric oxygen to near modern values atthe end of the Precambrian. Geologic constraints indicate thatthe excursion lasted between 25 and 50 m.y., requiring a DOCpool thousands of times to 10,000 times the modern inventoryto conform with carbon isotope mass balance calculations fora -12 excursion. At the consequent rates of DOC oxidation,oceanic sulfate and oxygen in the atmosphere and oceans areexhausted on a time scale of 800 k.y. Oxidant depletion isincompatible with independent geochemical and biological indicatorsthat show oceanic sulfate and oxygen levels were maintainedor increased during the Shuram excursion. Furthermore, a DOC-drivenexcursion does not explain strong covariation between the carbonand oxygen isotope record. These indicators show that negativeisotope excursions recorded in the Shuram and other Ediacaransections are unlikely to represent a global ocean signal. 19. Process-Scale Modeling of Atmosphere-Snowpack Exchange of Nitrogen Oxides Science.gov (United States) Murray, K. A.; Doskey, P. V.; Ganzeveld, L. 2013-12-01 Snowpack over glacial ice is a reservoir for reactive nitrogen gases. Previous studies indicate nitrogen oxides (NOx) are generated in snowpack interstitial air through photolysis of nitrate (NO3-). Gradients in NOx mixing ratios between snowpack interstitial air and the overlying atmosphere regulate exchange of NOx with snowpack, which affects the Arctic ozone budget and climate. To better understand the dynamics of cryosphere-atmosphere exchange of NOx in the Arctic, we collected 2 years of meteorological and chemical data in and above the snowpack at Summit, Greenland. The comprehensive dataset indicates NOx emissions are episodic, with NOx enhancements in snowpack in early spring during high wind speed events (10-20 mph), which elevate NOx levels to ~500 pptv at depths of 2.5 m. Analysis of the observations will be based upon application of a 1-D process-scale model of atmosphere-snowpack exchange of NOx. The model will include representations of the snowpack chemistry in gas and aqueous phases, mass transfer of chemical species between phases, and physical transport by diffusion and wind pumping. The model will calculate the chemical and physical tendencies in three dimensions: depth, time, and intensity. Analysis of the tendencies will allow us to perform model sensitivity tests of pertinent snowpack physical and chemical processes. The end-goal of the project is to simplify the major tendencies into a parameterized model add-on for use in global models to determine the importance of properly representing snowpack in global model simulations. 20. Emission to atmosphere of tritiated water formed at soil surface by oxidation of HT International Nuclear Information System (INIS) In the event of a release of molecular tritium to atmosphere, some tritium can oxidized at soil surface and be gradually re-emitted to atmosphere as HTO. The two processes are characterized by a deposition velocity and an emission rate, which are commonly used in deposition/emission models designed to calculate the concentrations of HTO in atmosphere. A technique has been developed to determine the emission rate and its evolution, by covering a small area of undisturbed soil by a field chamber, exposing the enclosed soil to molecular tritium, then determining the changes in HTO vapour content of a measured air-stream passing through the chamber. The emission rate is derived by dividing the amount of HTO extracted from the chamber during a given period of time, by the average amount of HTO contained in the soil during the same period. First experiments have been done on bare and grass-covered soils. The data obtained from these small-scale field experiments are consistent with those obtained from a full-scale field study carried out at nearly the same place 1. Electrochemical capacitance of iron oxide nanotube (Fe-NT): effect of annealing atmospheres Science.gov (United States) Sarma, Biplab; Jurovitzki, Abraham L.; Ray, Rupashree S.; Smith, York R.; Mohanty, Swomitra K.; Misra, Mano 2015-07-01 The effect of annealing atmosphere on the supercapacitance behavior of iron oxide nanotube (Fe-NT) electrodes has been explored and reported here. Iron oxide nanotubes were synthesized on a pure iron substrate through an electrochemical anodization process in an ethylene glycol solution containing 3% H2O and 0.5 wt.% NH4F. Subsequently, the annealing of the nanotubes was carried out at 500 °C for 2 h in various gas atmospheres such as air, oxygen (O2), nitrogen (N2), and argon (Ar). The morphology and crystal phases evolved after the annealing processes were examined via field emission scanning electron microscopy, x-ray diffraction, Raman spectroscopy, and x-ray photoelectron spectroscopy. The electrochemical capacitance properties of the annealed Fe-NT electrodes were evaluated by conducting cyclic voltammetry (CV), galvanostatic charge-discharge, and electrochemical impedance spectroscopy tests in the Li2SO4 electrolyte. Based on these experiments, it was found that the capacitance of the Fe-NT electrodes annealed in air and O2 atmospheres shows mixed behavior comprising both the electric double layer and pseudocapacitance. However, annealing in N2 and Ar environments resulted in well-defined redox peaks in the CV profiles of the Fe-NT electrodes, which are therefore attributed to the relatively higher pseudonature of the capacitance in these electrodes. Based on the galvanostatic charge-discharge studies, the specific capacitance achieved in the Fe-NT electrode after annealing in Ar was about 300 mF cm-2, which was about twice the value obtained for N2-annealed Fe-NTs and three times higher than those annealed in air and O2. The experiments also demonstrated excellent cycle stability for the Fe-NT electrodes with 83%-85% capacitance retention, even after many charge-discharge cycles, irrespective of the gas atmospheres used during annealing. The increase in the specific capacitance was discussed in terms of increased oxygen vacancies as a result of the 2. Product characteristics from the torrefaction of oil palm fiber pellets in inert and oxidative atmospheres. Science.gov (United States) Chen, Wei-Hsin; Zhuang, Yi-Qing; Liu, Shih-Hsien; Juang, Tarng-Tzuen; Tsai, Chi-Ming 2016-01-01 The aim of this work was to study the characteristics of solid and liquid products from the torrefaction of oil palm fiber pellets (OPFP) in inert and oxidative environments. The torrefaction temperature and O2 concentration in the carrier gas were in the ranges of 275-350°C and 0-10 vol%, respectively, while the torrefaction duration was 30 min. The oxidative torrefaction of OPFP at 275°C drastically intensified the HHV of the biomass when compared to the non-oxidative torrefaction. OPFP torrefied at 300°C is recommended to upgrade the biomass, irrespective of the atmosphere. The HHV of condensed liquid was between 10.1 and 13.2 MJ kg(-)(1), and was promoted to 23.2-28.7 MJ kg(-)(1) following dewatering. This accounts for 92-139% improvement in the calorific value of the liquid. This reveals that the recovery of condensed liquid with dewatering is able to enhance the energy efficiency of a torrefaction system. 3. Product characteristics from the torrefaction of oil palm fiber pellets in inert and oxidative atmospheres. Science.gov (United States) Chen, Wei-Hsin; Zhuang, Yi-Qing; Liu, Shih-Hsien; Juang, Tarng-Tzuen; Tsai, Chi-Ming 2016-01-01 The aim of this work was to study the characteristics of solid and liquid products from the torrefaction of oil palm fiber pellets (OPFP) in inert and oxidative environments. The torrefaction temperature and O2 concentration in the carrier gas were in the ranges of 275-350°C and 0-10 vol%, respectively, while the torrefaction duration was 30 min. The oxidative torrefaction of OPFP at 275°C drastically intensified the HHV of the biomass when compared to the non-oxidative torrefaction. OPFP torrefied at 300°C is recommended to upgrade the biomass, irrespective of the atmosphere. The HHV of condensed liquid was between 10.1 and 13.2 MJ kg(-)(1), and was promoted to 23.2-28.7 MJ kg(-)(1) following dewatering. This accounts for 92-139% improvement in the calorific value of the liquid. This reveals that the recovery of condensed liquid with dewatering is able to enhance the energy efficiency of a torrefaction system. PMID:26346262 4. Thermoeconomic analysis of large solid oxide fuel cell plants: Atmospheric vs. pressurized performance International Nuclear Information System (INIS) A detailed thermoeconomic analysis of two large solid oxide fuel cell-based power plants operating at atmospheric pressure and 20 bar, respectively, is assessed in this work. The analyzed systems employ SOFC-GT (gas turbine) modules as main power generators; a bottom HRSC (heat recovery steam cycle) to generate additional electricity from the SOFC-GT exhaust hot gases is also included. The thermodynamic and economic performance of the two plant configurations are studied in detail: the exergy analysis shows an enhanced exergetic performance for the pressurized cycle that features components with higher efficiency and consequently a lower rate of exergy destruction (∼20% less than the atmospheric plant). The economic analysis considers the capital cost of each component within the system and is developed aiming at estimating the levelized cost of electricity. In order to match both exergetic and economic parts, a rigorous thermoeconomic analysis following the theory of Valero and Bejan [1,2] is implemented. A well-defined set of rules for the exergoeconomic balance around each plant component is specified and specific cost balance equations are thus derived. Results show how pressurized plant outperforms the atmospheric one, with a (on exergo-economic base) cost of electricity of 47.7 $/MWh instead of 64.2$/MWh. Therefore, both exergetic and economic advantages result from the adoption of a pressurized SOFC-GT cycle in the framework of future advance power plants based on high-temperature fuel cells. - Highlights: • Exergy analysis of atmospheric and pressurized SOFC plants. • Exergy destruction in a fuel cell hybrid power plant. • Rigorous thermoeconomic methodology to assess the performance of different power generation plants. • Economic performance of SOFC plants 5. Atmospheric nitrous oxide observations above the oceanic surface during the first Chinese Arctic Research Expedition Institute of Scientific and Technical Information of China (English) 朱仁斌; 孙立广; 谢周清; 赵俊琳 2003-01-01 339 gas samples above oceanic surface were collected on the cruise of "Xuelong" expeditionary ship and nitrous oxide concentrations were analyzed in the laboratory. Results showed that Atmospheric average N20 concentration was 309 ± 3.8nL/L above the surface of northern Pacific and Arctic ocean. N2O concentrations were significantly different on the northbound and southbound track in the range of the same latitude, 308.0 ± 3.5 nL/L from Shanghai harbor to the Arctic and 311.9 ± 2.5 nL/L from the Arctic to Shanghai harbor. N2O concentration had a greater changing magnitude on the mid- and high-latitude oceanic surface of northern Pacific Ocean than in the other latitudinal ranges. The correlation between the concentrations of the compositions in the aerosol samples and atmospheric N2O showed that continental sources had a great contribution on atmospheric N2 O concentration above the oceanic surface. Atmospheric N2O concentration significantly increased when the expeditionary ship approached Shanghai harbor. The average N2O concentrations were 315.1 ±2.5 nL/L, 307.2 ±1.4 nL/L and 306.2 ±0.7 nL/L, respectively, at Shanghai harbor, at ice stations and at floating ices. The distribution of N2O concentrations was related with air pressure and temperature above the mid- and high-latitude Pacific Ocean. 6. THE EFFECT OF OLIVE BY PRODUCTS AND THEIR EXTRACTS ON ANTIOXIDATIVE STATUS OF LAYING HENS AND OXIDATIVE STABILITY OF EGGS ENRICHED WITH N-3 FATTY ACIDS Directory of Open Access Journals (Sweden) Vida Rezar 2015-09-01 Full Text Available The aim of the study was to assess the effects olive leaves, pulp and their extract supplementation on performance, antioxidant status and oxidative stability of eggs. Oxidative stress was induced by the addition of 6% linseed oil in the feed. 94 individually caged laying hens, 40 weeks old, were included in the study. Animals were divided into 6 groups. The feed of each group was composed of a basic feed, supplemented with: group Cont - no supplement, Vit E - 150 IU of α-tocopherol acetate /kg, Olive L - 1% of olive leaves, Olive Ex - extract from olive leaves, the Pulp group - 1% of dried and ground pulp and Pulp Ex - extract from pulp. Based on the results we found out that supplementation of vitamin E, olive leaves, pulp and their extracts had no effect on the performance of hens and showed neither a lymphocyte DNA damage preventive activity nor influence malondialdehyde (MDA concentration in plasma. The results suggest that α-tocopherol acetate and olive leaves supplementation had significant effect on the MDA content of the stored eggs. Supplements, except vitamin E had neither influence on antioxidant activity (ACL in eggs nor on n-3 PUFA in fresh and 40 days stored eggs. 7. Response of Atmospheric-Methane Oxidation to Methane-Flux Manipulation in a Laboratory Soil-Column Experiment Science.gov (United States) Schroth, M. H.; Mignola, I.; Henneberger, R. 2015-12-01 Upland soils are an important sink for atmospheric methane (CH4). Uptake of atmospheric CH4 in soils is generally diffusion limited, and is mediated by aerobic CH4 oxidizing bacteria (MOB) that possess a high-affinity form of a key enzyme, allowing CH4 consumption at near-atmospheric concentrations (≤ 1.9 µL/L). As cultivation attempts for these high-affinity MOB have shown little success, there remains much speculation regarding their functioning in different environments. For example, it is frequently assumed that they are highly sensitive to physical disturbance, but their response in activity and abundance to changes in substrate availability remains largely unknown. We present results of a laboratory column experiment conducted to investigate the response in activity and abundance of high-affinity MOB to an increase in CH4 flux. Intact soil cores, collected at a field site where atmospheric CH4 oxidation activity is frequently quantified, were transferred into two 1-m-long, 12-cm-dia. columns. The columns were operated at constant temperature in the dark, their headspace being continuously flushed with air. Diffusive gas-transport conditions were maintained in the reference column, whereas CH4 flux was increased in several steps in the treatment column by inducing advective gas flow using a diaphragm pump. Soil-gas samples periodically collected from ports installed along the length of the columns were analyzed for CH4 content. Together with measurements of soil-water content, atmospheric CH4 oxidation was quantified using the soil-profile method. First results indicate that atmospheric CH4 oxidation activity comparable with the field was maintained in the reference column throughout the experiment. Moreover, high-affinity MOB quickly adjusted to an increase in CH4 flux in the treatment column, efficiently consuming CH4. Quantification of MOB abundance is currently ongoing. Our data provide new insights into controls on atmospheric CH4 oxidation in soils. 8. On-line coating of glass with tin oxide by atmospheric pressure chemical vapor deposition. Energy Technology Data Exchange (ETDEWEB) Allendorf, Mark D.; Sopko, J.F. (PPF Industries, Pittsburgh, PA); Houf, William G.; Chae, Yong Kee; McDaniel, Anthony H.; Li, M. (PPF Industries, Pittsburgh, PA); McCamy, J.W. (PPF Industries, Pittsburgh, PA) 2006-11-01 Atmospheric pressure chemical vapor deposition (APCVD) of tin oxide is a very important manufacturing technique used in the production of low-emissivity glass. It is also the primary method used to provide wear-resistant coatings on glass containers. The complexity of these systems, which involve chemical reactions in both the gas phase and on the deposition surface, as well as complex fluid dynamics, makes process optimization and design of new coating reactors a very difficult task. In 2001 the U.S. Dept. of Energy Industrial Technologies Program Glass Industry of the Future Team funded a project to address the need for more accurate data concerning the tin oxide APCVD process. This report presents a case study of on-line APCVD using organometallic precursors, which are the primary reactants used in industrial coating processes. Research staff at Sandia National Laboratories in Livermore, CA, and the PPG Industries Glass Technology Center in Pittsburgh, PA collaborated to produce this work. In this report, we describe a detailed investigation of the factors controlling the growth of tin oxide films. The report begins with a discussion of the basic elements of the deposition chemistry, including gas-phase thermochemistry of tin species and mechanisms of chemical reactions involved in the decomposition of tin precursors. These results provide the basis for experimental investigations in which tin oxide growth rates were measured as a function of all major process variables. The experiments focused on growth from monobutyltintrichloride (MBTC) since this is one of the two primary precursors used industrially. There are almost no reliable growth-rate data available for this precursor. Robust models describing the growth rate as a function of these variables are derived from modeling of these data. Finally, the results are used to conduct computational fluid dynamic simulations of both pilot- and full-scale coating reactors. As a result, general conclusions are 9. Fractionation of sulfur isotopes during heterogeneous oxidation of SO2 in the atmosphere Science.gov (United States) Harris, E. J.; Sinha, B.; Hoppe, P.; Crowley, J.; Borrmann, S.; Foley, S. F.; Gnauk, T.; Van Pinxteren, D.; Herrmann, H. 2011-12-01 Sulfate and sulfur dioxide play an important role in environmental chemistry and climate, particularly through their effect on aerosols. Processing of aerosol through sulfate addition in clouds, which causes both hygroscopicity changes and mass increases, has been shown to modify the cloud condensation nucleus spectrum, leading to important climatological effects (Bower et al. 1997, Hegg et al. 2004). However, the uptake of sulfate and SO2 to aerosol in clouds is not well constrained, nor is it resolved for different particle types and sizes (Kasper-Giebl et al. 2000, Barrie et al. 2001). Measurements of stable sulfur isotopes can be used to investigate the chemistry of SO2 in the environment, providing insight into sources, sinks and oxidation pathways. Typical isotopic compositions for many sources have been measured, and the major current limitation is the lack of reliable fractionation factors - characteristic changes in isotopic composition caused by chemical reactions - with which to interpret the data. Laboratory values of fractionation factors for the major oxidation reactions have been measured in previous work, however there are no measurements or models to represent isotopic fractionation during heterogeneous oxidation on complex atmospheric surfaces. In this work the sulfur isotopic fractionation factors for SO2 oxidation have been measured on Sahara dust, obtained from the Cape Verde Islands, and sea salt aerosol, which was synthesised in the laboratory according to Millero (1974), modified to contain no sulfate. Sulfur dioxide with a known isotopic composition was oxidised on these surfaces under a variety of conditions including irradiation and ozonation, and the sulfur isotopic composition of the product sulfate was measured with the Cameca NanoSIMS 50. These laboratory results were then used to investigate the uptake of sulfur to particles in an orographic cloud during the HCCT campaign. The campaign took place at the Schmücke mountain in Germany 10. Using Magnetism to Characterize and Distinguish High Coercivity Iron Oxide and Oxyhydroxide Minerals in Atmospheric Dust Science.gov (United States) Yauk, Kimberly E. Natural atmospheric dust samples collected from the American southwest and globally were measured using magnetic methods in order to separate remanence attributed to the high coercivity iron oxide and oxyhydroxide minerals hematite and goethite. Dust collected from mountain snow and dust source areas in nearby arid plains were analyzed using traditional room- and low temperature methods. Additional methods were created to better examine the weak, high coercivity components. Combinations of high fields (2.5-9 T), low temperatures (10-300 K), partial AF demagnetization, and thermal demagnetization to 400 K were implemented to separate each component. Percentages of remanence attributed to magnetite, hematite, and goethite were compared to results found by HIRM (hard isothermal remanent magnetization) and Mossbauer spectroscopy with good correlation and to coercivity unmixing methods without correlation. TRM (thermoremanent magnetization) was found to be an important step in magnetizing a greater portion of the goethite fraction. Further procedures for characterizing nano grain sizes would be illuminating. 11. Coarsening of Pd nanoparticles in an oxidizing atmosphere studied by in situ TEM DEFF Research Database (Denmark) Simonsen, Søren Bredmose; Chorkendorff, Ib; Dahl, Søren; 2016-01-01 The coarsening of supported palladium nanoparticles in an oxidizing atmosphere was studied in situ by means of transmission electron microscopy (TEM). Specifically, the Pd nanoparticles were dispersed on a planar and amorphous Al2O3 support and were observed during the exposure to 10 mbar technical...... air at 650 °C. Time-resolved TEM image series reveal that the Pd nanoparticles were immobile and that a few percent of the nanoparticles grew or shrank, indicating a coarsening process mediated by the Ostwald ripening mechanism. The TEM image contrast suggests that the largest nanoparticles tended...... to wet the Al2O3 support to a higher degree than the smaller nanoparticles and that the distribution of projected particle sizes consequently broadens by the appearance of an asymmetric tail toward the larger particle sizes. A comparison with computer simulations based on a simple mean-field model... 12. Nitric oxide delta band emission in the earth's atmosphere - Comparison of a measurement and a theory Science.gov (United States) Rusch, D. W.; Sharp, W. E. 1981-01-01 Attention is given to the altitude dependent emission rate in the delta-bands of nitric oxide as measured in the earth's atmosphere at night by a scanning ultraviolet spectrometer. It is noted that the reaction responsible is the two-body association of nitrogen and oxygen atoms. The measurements show a vertical intensity beneath the layer for the delta-band system of 19 R. The horizontal emission rate is found to increase from 70 R at 117 km to 140 R at 150 km. The data are analyzed with a one-dimensional, time-dependent, vertical-transport model of odd nitrogen photochemistry. The calculated and measured intensities agree so long as the quenching of N(2D) by atomic oxygen is near 5 x 10 to the -13 cu cm/sec. 13. Mechanical characterisation of tungsten–1 wt.% yttrium oxide as a function of temperature and atmosphere Energy Technology Data Exchange (ETDEWEB) Palacios, T.; Jiménez, A. [Materials Science Department, Technical University of Madrid, E.T.S. de Ingenieros de Caminos, Canales y Puertos, C/Profesor Aranguren s/n, 28040 Madrid (Spain); Muñóz, A.; Monge, M.A.; Ballesteros, C. [Departamento de Física, Universidad Carlos III de Madrid, Leganés (Spain); Pastor, J.Y. [Materials Science Department, Technical University of Madrid, E.T.S. de Ingenieros de Caminos, Canales y Puertos, C/Profesor Aranguren s/n, 28040 Madrid (Spain) 2014-11-15 This study evaluates the mechanical behaviour of an Y{sub 2}O{sub 3}-dispersed tungsten (W) alloy and compares it to a pure W reference material. Both materials were processed via mechanical alloying (MA) and subsequent hot isostatic pressing (HIP). We performed non-standard three-point bending (TPB) tests in both an oxidising atmosphere and vacuum across a temperature range from 77 K, obtained via immersion in liquid nitrogen, to 1473 K to determine the mechanical strength, yield strength and fracture toughness. This research aims to evaluate how the mechanical behaviour of the alloy is affected by oxides formed within the material at high temperatures, primarily from 873 K, when the materials undergo a massive thermal degradation. The results indicate that the alloy is brittle to a high temperature (1473 K) under both atmospheres and that the mechanical properties degrade significantly above 873 K. We also used Vickers microhardness tests and the dynamic modulus by impulse excitation technique (IET) to determine the elastic modulus at room temperature. Moreover, we performed nanoindentation tests to determine the effect of size on the hardness and elastic modulus; however, no significant differences were found. Additionally, we calculated the relative density of the samples to assess the porosity of the alloy. Finally, we analysed the microstructure and fracture surfaces of the tested materials via field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). In this way, the relationship between the macroscopic mechanical properties and micromechanisms of failure could be determined based on the temperature and oxides formed. 14. Oxygen dynamics in the aftermath of the Great Oxidation of Earth’s atmosphere Science.gov (United States) Canfield, Donald E.; Ngombi-Pemba, Lauriss; Hammarlund, Emma U.; Bengtson, Stefan; Chaussidon, Marc; Gauthier-Lafaye, François; Meunier, Alain; Riboulleau, Armelle; Rollion-Bard, Claire; Rouxel, Olivier; Asael, Dan; Pierson-Wickmann, Anne-Catherine; El Albani, Abderrazak 2013-01-01 The oxygen content of Earth’s atmosphere has varied greatly through time, progressing from exceptionally low levels before about 2.3 billion years ago, to much higher levels afterward. In the absence of better information, we usually view the progress in Earth’s oxygenation as a series of steps followed by periods of relative stasis. In contrast to this view, and as reported here, a dynamic evolution of Earth’s oxygenation is recorded in ancient sediments from the Republic of Gabon from between about 2,150 and 2,080 million years ago. The oldest sediments in this sequence were deposited in well-oxygenated deep waters whereas the youngest were deposited in euxinic waters, which were globally extensive. These fluctuations in oxygenation were likely driven by the comings and goings of the Lomagundi carbon isotope excursion, the longest–lived positive δ13C excursion in Earth history, generating a huge oxygen source to the atmosphere. As the Lomagundi event waned, the oxygen source became a net oxygen sink as Lomagundi organic matter became oxidized, driving oxygen to low levels; this state may have persisted for 200 million years. PMID:24082125 15. Oxygen dynamics in the aftermath of the Great Oxidation of Earth's atmosphere. Science.gov (United States) Canfield, Donald E; Ngombi-Pemba, Lauriss; Hammarlund, Emma U; Bengtson, Stefan; Chaussidon, Marc; Gauthier-Lafaye, François; Meunier, Alain; Riboulleau, Armelle; Rollion-Bard, Claire; Rouxel, Olivier; Asael, Dan; Pierson-Wickmann, Anne-Catherine; El Albani, Abderrazak 2013-10-15 The oxygen content of Earth's atmosphere has varied greatly through time, progressing from exceptionally low levels before about 2.3 billion years ago, to much higher levels afterward. In the absence of better information, we usually view the progress in Earth's oxygenation as a series of steps followed by periods of relative stasis. In contrast to this view, and as reported here, a dynamic evolution of Earth's oxygenation is recorded in ancient sediments from the Republic of Gabon from between about 2,150 and 2,080 million years ago. The oldest sediments in this sequence were deposited in well-oxygenated deep waters whereas the youngest were deposited in euxinic waters, which were globally extensive. These fluctuations in oxygenation were likely driven by the comings and goings of the Lomagundi carbon isotope excursion, the longest-lived positive δ(13)C excursion in Earth history, generating a huge oxygen source to the atmosphere. As the Lomagundi event waned, the oxygen source became a net oxygen sink as Lomagundi organic matter became oxidized, driving oxygen to low levels; this state may have persisted for 200 million years. 16. Atmospheric-pressure plasma-enhanced chemical vapor deposition of electrochromic organonickel oxide thin films with an atmospheric pressure plasma jet International Nuclear Information System (INIS) Deposition of electrochromic organonickel oxide (NiOxCy) films onto glass/indium tin oxide (ITO) substrates using atmospheric-pressure plasma-enhanced chemical vapor deposition with an atmospheric pressure plasma jet under various precursor injection angles is investigated. A precursor [nickelocene, Ni(C5H5)2] vapor, carried by argon gas and mixed with oxygen gas, is injected into an air plasma torch for the deposition of NiOxCy films by a short exposure of the substrate, 20 s, in the plasma. Uniform light modulation on glass/ITO/NiOxCy is produced while the moving glass/ITO substrate is exposed to the plasma torch at room temperature (∼ 23 °C) and under atmospheric pressure. Light modulation with up to a 40.9% transmittance variation at a wavelength of 513.9 nm under Li+ intercalation and de-intercalation in a 1 M LiClO4–propylene carbonate electrolyte is achieved. - Highlights: ► Rapid deposition of electrochromic NiOxCy film by atmospheric pressure plasma jet ► Uniform light modulation on NiOxCy film is produced. ► Nano-grains in NiOxCy films offer fast coloration and bleaching 17. The impact of Southwest Airline's contribution to atmospheric Carbon Dioxide and Nitrous Oxide totals Science.gov (United States) Wilkerson, Cody L. Over the last century, aviation has grown to become an economical juggernaut. The industry creates innovation, connects people, and maintains a safety goal unlike any other field. However, as the world becomes more populated with technology and individuals, a general curiosity as to how human activity effects the planet is becoming of greater interest. This study presents what one domestic airline in the United States, Southwest Airlines, contributes to the atmospheric make-up of the planet. Utilizing various sources of quantifiable data, an outcome was reached that shows the amount of Carbon Dioxide and Nitrous Oxide produced by Southwest Airlines from 2002 to 2013. This topic was chosen due to the fact that there are no real quantifiable values of emission statistics from airlines available to the public. Further investigation allowed for Southwest Airlines to be compared to the overall Carbon Dioxide and Nitrous Oxide contributions of the United States for the year 2011. The results showed that with the absence of any set standard on emissions, it is vital that one should be established. The data showed that the current ICAO standard emission values showed a higher level of emissions than when Southwest Airline's fleet was analyzed using their actual fleet mix. 18. Mainz Isoprene Mechanism 2 (MIM2: an isoprene oxidation mechanism for regional and global atmospheric modelling Directory of Open Access Journals (Sweden) D. Taraborrelli 2008-07-01 Full Text Available We present an oxidation mechanism of intermediate size for isoprene (2-methyl-1,3-butadiene suitable for simulations in regional and global atmospheric chemistry models, which we call MIM2. It is a reduction of the corresponding detailed mechanism in the Master Chemical Mechanism (MCM v3.1 and intended as the second version of the well-established Mainz Isoprene Mechanism (MIM. Our aim is to improve the representation of tropospheric chemistry in regional and global models under all NOx regimes. We evaluate MIM2 and re-evaluate MIM through comparisons with MCM v3.1. We find that MIM and MIM2 compute similar O3, OH and isoprene mixing ratios. Unlike MIM, MIM2 produces small relative biases for NOx and organic nitrogen-containing species due to a good representation of the alkyl and peroxy acyl nitrates (RONO2 and RC(OOONO2. Moreover, MIM2 computes only small relative biases with respect to hydrogen peroxide (H2O2, methyl peroxide (CH3OOH, methanol (CH3OH, formaldehyde (HCHO, peroxy acetyl nitrate (PAN, and formic and acetic acids (HCOOH and CH3C(OOH, being always below ≈6% in all NOx scenarios studied. Most of the isoprene oxidation products are represented explicitly, including methyl vinyl ketone (MVK, methacrolein (MACR, hydroxyacetone and methyl glyoxal. MIM2 is mass-conserving with respect to carbon, including CO2 as well. Therefore, it is suitable for studies assessing carbon monoxide (CO from biogenic sources, as well as for studies focused on the carbon cycle. Compared to MIM, MIM2 considers new species like acetaldehyde (CH3CHO, propene (CH2=CHCH3 and glyoxal (CHOCHO with global chemical production rates for the year 2005 of 7.3, 9.5 and 33.8 Tg/yr, respectively. Our new mechanism is expected to substantially improve the results of atmospheric chemistry models by more 19. Effect of titanium oxide nanoparticle incorporation into nm thick coatings deposited using an atmospheric pressure plasma. Science.gov (United States) Denis, Dowling P; Barry, Twomey; Gerry, Byrne 2010-04-01 This study reports on the use of an atmospheric plasma technique to incorporate metal oxide nanoparticles into nm thick siloxane coatings. Titanium dioxide (TiO2) particles with diameters of 30-80 nm, were mixed with a number of different siloxanes-polydimethylsiloxane, hexamethyldisiloxane and tetraethylorthosilicate (TEOS). The TiO2/TEOS mixture was found to give the most stable suspension, possibly due to the higher surface tension of TEOS compared with the other siloxanes. TiO2/TEOS mixtures with 2 to 10% by weight of the metal oxide were prepared and were then nebulised into a helium/oxygen atmospheric plasma. Polyethylene terepthalate (PET) and silicon wafer substrates were passed through this plasma using a reel-to-reel substrate manipulation system. SEM combined with EDX was used to examine the distribution of the metal oxide particles in the resultant coatings. The TEOS coating thickness without TiO2 addition was 9 nm. The composite coating consisted of a relatively homogeneous distribution of small agglomerates of the TiO2 nanoparticles in TEOS. A linear increase in the titanium surface concentration was observed with increase in the quantity of TiO2 added into the siloxane precursor. The chemical functionality of the siloxane coating was examined using FTIR spectroscopy and no significant spectrum differences was observed with the incorporation of the different concentrations of TiO2 into the polymer. There were also no changes observed in coating surface energy with TiO2 incorporation. Coating morphology was examined using optical profilometry and surface roughness (Ra) values increased from typical values of 0.8 nm for the TEOS coating to 4.1 nm for the TiO2/TEOS coating. The adhesion of the deposited coatings was compared using fragmentation tests. These were carried out through uniaxial tensile loading. The coating cracking pattern after applied strain of 20% was not observed to change significantly with the addition of TiO2 into the siloxane. PMID 20. Nitrogen oxide air pollution: atmospheric chemistry. 1979-August, 1980 (citations from the NTIS data base). Report for 1979-Aug 80 Energy Technology Data Exchange (ETDEWEB) Cavagnaro, D.M. 1980-10-01 Photochemical air pollution models, smog chemistry and reactivity, and SSt exhaust effects are covered in the bibliography. Auroral and upper atmospheric chemistry, and photochemistry of naturally occurring nitrogen oxides are excluded. (This updated bibliography contains 63 citations, 40 of which are new entries to the previous edition.) 1. Influence of the atmospheric species water, oxygen, nitrogen and carbon dioxide on the degradation of aluminum doped zinc oxide layers NARCIS (Netherlands) Theelen, M.; Dasgupta, S.; Vroon, Z.; Kniknie, B.; Barreau, N.; Berkum, J. van; Zeman, M. 2014-01-01 Aluminum doped zinc oxide (ZnO:Al) layers were exposed to the atmospheric gases carbon dioxide (CO2), oxygen (O2), nitrogen (N 2) and air as well as liquid H2O purged with these gases, in order to investigate the chemical degradation behavior of these layers. The samples were analyzed by electrical, 2. Effect of oxygen level on the oxidative stability of two different retail pork products stored using modified atmosphere packaging (MAP) DEFF Research Database (Denmark) Spanos, Dimitrios; Ann Tørngren, Mari; Christensen, Mette; 2016-01-01 The characteristics and the oxidative stability of pork steaks and of pork mince were investigated during 2, 5 and 7 days of refrigerated storage using oxygen (O2) levels of 0%, 20%, 50% and 80% in modified atmosphere packaging (MAP). Steaks stored during 7 days were not affected by an increase... 3. Effect of Kovar alloy oxidized in simulated N2/H2O atmosphere on its sealing with glass Institute of Scientific and Technical Information of China (English) Dawei Luo; Wenbo Leng; Zhuoshen Shen 2008-01-01 The effect of Kovar alloy oxidized in simulated field atmosphere on its sealing with glass was studied in this article. After Kovar plates and pins were preoxidized in N2 with 0℃, 10℃ and 20℃ dew points at 1000℃ for different times, Fe3O4 and Fe2O3 existed in the oxidation products on Kovar surface, and the quantity of Fe2O3 increased with increasing dew point and oxidation time.Then they were sealed with borosilicate glass insulator at 1030℃ for 20 min. The results indicated that the type and quantity of oxidation products would directly influence the quality of glass-to-metal seals. With the increase of oxidation products, gas bubbles in the glass insulator were more serious, the climbing height of glass along the pins was higher, and corrosion of Kovar pins caused from the molten glass was transformed from uniform to the localized. 4. Atmospheric plasma generates oxygen atoms as oxidizing species in aqueous solutions Science.gov (United States) Mokhtar Hefny, Mohamed; Pattyn, Cedric; Lukes, Petr; Benedikt, Jan 2016-10-01 A remote microscale atmospheric pressure plasma jet (µAPPJ) with He, He/H2O, He/O2, and He/O2/H2O gas mixtures was used to study the transport of reactive species from the gas phase into the liquid and the following aqueous phase chemistry. The effects induced by the µAPPJ in water were quantitatively studied using phenol as a chemical probe and by measuring H2O2 concentration and pH values. These results were combined with the analysis of the absolute densities of the reactive species and the modeling of convective/diffusion transport and recombination reactions in the effluent of the plasma jet. Additionally, modified plasma jets were used to show that the role of emitted photons in aqueous chemistry is negligible for these plasma sources. The fastest phenol degradation was measured for the He/O2 plasma, followed by He/H2O, He/O2/H2O, and He plasmas. The modeled quantitative flux of O atoms into the liquid in the He/O2 plasma case was highly comparable with the phenol degradation rate and showed a very high transfer efficiency of reactive species from the plasma into the liquid, where more than half of the O atoms leaving the jet nozzle entered the liquid. The results indicate that the high oxidative effect of He/O2 plasma was primarily due to solvated O atoms, whereas OH radicals dominated the oxidative effects induced in water by plasmas with other gas mixtures. These findings help to understand, in a quantitative way, the complex interaction of cold atmospheric plasmas with aqueous solutions and will allow a better understanding of the interaction of these plasmas with water or buffered solutions containing biological macromolecules, microorganisms, or even eukaryotic cells. Additionally, the µAPPJ He/O2 plasma source seems to be an ideal tool for the generation of O atoms in aqueous solutions for any future studies of their reactivity. 5. Mainz Isoprene Mechanism 2 (MIM2: an isoprene oxidation mechanism for regional and global atmospheric modelling Directory of Open Access Journals (Sweden) D. Taraborrelli 2009-04-01 Full Text Available We present an oxidation mechanism of intermediate size for isoprene (2-methyl-1,3-butadiene suitable for simulations in regional and global atmospheric chemistry models, which we call MIM2. It is a reduction of the corresponding detailed mechanism in the Master Chemical Mechanism (MCM v3.1 and intended as the second version of the well-established Mainz Isoprene Mechanism (MIM. Our aim is to improve the representation of tropospheric chemistry in regional and global models under all NOx regimes. We evaluate MIM2 and re-evaluate MIM through comparisons with MCM v3.1. We find that MIM and MIM2 compute similar O3, OH and isoprene mixing ratios. Unlike MIM, MIM2 produces small relative biases for NOx and organic nitrogen-containing species due to a good representation of the alkyl and peroxy acyl nitrates (RONO2 and RC(OOONO2. Moreover, MIM2 computes only small relative biases with respect to hydrogen peroxide (H2O2, methyl peroxide (CH3OOH, methanol (CH3OH, formaldehyde (HCHO, peroxy acetyl nitrate (PAN, and formic and acetic acids (HCOOH and CH3C(OOH, being always below ≈6% in all NOx scenarios studied. Most of the isoprene oxidation products are represented explicitly, including methyl vinyl ketone (MVK, methacrolein (MACR, hydroxyacetone and methyl glyoxal. MIM2 is mass-conserving with respect to carbon, including CO2 as well. Therefore, it is suitable for studies assessing carbon monoxide (CO from biogenic sources, as well as for studies focused on the carbon cycle. Compared to MIM, MIM2 considers new species like acetaldehyde (CH3CHO, propene (CH2=CHCH3 and glyoxal (CHOCHO with global chemical production rates for the year 2005 of 7.3, 9.5 and 33.8 Tg/yr, respectively. Our new mechanism is expected to substantially improve the results of atmospheric chemistry models by 6. The magnetic and oxidation behavior of bare and silica-coated iron oxide nanoparticles synthesized by reverse co-precipitation of ferrous ion (Fe2+) in ambient atmosphere International Nuclear Information System (INIS) The synthesis of iron oxide nanoparticles, i.e., magnetite was attempted by using only ferrous ion (Fe2+) as a magnetite precursor, under an ambient atmosphere. The room temperature reverse co-precipitation method was used, by applying two synthesis protocols. The freshly prepared iron oxide was also immediately coated with Stöber silica (SiO2) layer, forming the coreshell structure. The phase, stoichiometry, crystallite and the particle size of the synthesized powders were determined by using X-ray diffraction (XRD) and transmission electron microscope (TEM), while the magnetic and oxidation behaviors were studied by using the vibrating sample magnetometer (VSM) and Mössbauer spectroscopy. Based on the results, the bare iron oxide nanoparticles are in the stoichiometry between the magnetite and the maghemite stoichiometry, i.e., oxidation occurs. This oxidation is depending on the synthesis protocols used. With the silica coating, the oxidation can be prevented, as suggested by the fits of Mössbauer spectra and low temperature magnetic measurement. - Highlights: • Synthesis of magnetite was attempted by using ferrous ion (Fe2+) in air. • The synthesized particle has a stoichiometry in between magnetite and maghemite. • Silica shell partly prevented the oxidation as suggested by magnetic and Mössbauer study 7. Conductive zinc oxide thin film coatings by combustion chemical vapour deposition at atmospheric pressure International Nuclear Information System (INIS) We have established a combustion chemical vapour deposition (C-CVD) system for the deposition of zinc oxide (ZnO) at atmospheric pressure. This C-CVD process has the advantage of a short exposure of the substrates to the flame. It is also potentially applicable as an inline coating system. Fundamental studies were performed on undoped ZnO. The specific resistivity of these layers strongly depends on the film thickness and decreases with increasing thickness. As the lowest resistivities, values of about 2.0 · 10−1 Ωcm are achieved. Ultra-violet photoemission spectra show the valence band structure of the deposited ZnO. The work function and valence band edge were determined. UV–vis spectra were taken to investigate the transmission of the coated glass samples. From these spectra the band gap energy was obtained. Raman spectroscopy as well as infrared spectroscopy confirmed the presence of ordered ZnO crystallites. The X-ray diffraction verified this result and illustrates the hexagonal structure. In the mid-infrared range precursor deposits were detected for low substrate temperatures. - Highlights: ► Zinc oxide (ZnO) films are conductive in the range of 2.0 · 10−1 Ωcm. ► X-ray diffraction, Raman and infrared spectroscopy indicate crystalline ZnO films. ► Precursor deposits were proved within the films for low growing temperatures. ► Band gap energy changes are achieved due to different growing temperatures 8. Modeling the possible role of iodine oxides in atmospheric new particle formation Directory of Open Access Journals (Sweden) S. Pechtl 2006-01-01 Full Text Available We studied the possible role of iodine oxides in atmospheric new particle formation with the one-dimensional marine boundary layer model MISTRA, which includes chemistry in the gas and aerosol phase as well as aerosol microphysics. The chemical reaction set focuses on halogen (Cl-Br-I chemistry. We included a two-step nucleation parameterization, where in the first step, the 'real' nucleation process is parameterized, i.e., the formation of cluster-sized nuclei via homogeneous condensation of gases. We considered both ternary sulfuric acid-ammonia-water nucleation and homomolecular homogeneous OIO nucleation. For the latter, we derived a parameterization based on combined laboratory-model studies. The second step of the nucleation parameterization treats the 'apparent' nucleation rate, i.e., the growth of clusters into the model's lowest size bin by condensable vapors such as OIO. We compared different scenarios for a clean marine versus a polluted continental background atmosphere. In every scenario, we assumed the air to move, independent of its origin, first over a coastal region (where it is exposed to surface fluxes of different reactive iodine precursors and later over the open ocean. According to these sensitivity studies, in the clean marine background atmosphere OIO can be responsible for both homogeneous nuclei formation and the subsequent growth of the clusters to detectable sizes. In contrast to this, in the continental case with its higher levels of pollutants, gas phase OIO mixing ratios, and hence related nucleation rates, are significantly lower. Compared to ternary H2SO4-NH3-H2O nucleation, homogeneous OIO nucleation can be neglected for new particle formation in this case, but OIO can contribute to early particle growth, i.e., to apparent nucleation rates. In general, we found OIO to be more important for the growth of newly formed particles than for the formation of new nuclei. According to our studies, observations of 9. Fog composition at Baengnyeong Island in the Eastern Yellow Sea: detecting markers of aqueous atmospheric oxidations Directory of Open Access Journals (Sweden) A. J. Boris 2015-09-01 Full Text Available Samples of fog water were collected at Baengnyeong Island (BYI in the Yellow Sea during the summer of 2014. The most abundant chemical species in the fog water were NH4+ (mean of 2220 μM, NO3− (1260 μM, SO4−2 (730 μM, and Na+ (551 μM, with substantial contributions from other ions consistent with marine and biomass burning influence on some dates. The pH of the samples ranged between 3.48 and 5.00, with a mean of 3.94, intermediate within pH values of fog/cloud water reported previously in Southeast Asia. Back trajectories (72 h showed that high relative humidity (> 80 % was encountered upwind of the sampling site by all but one of the sampled air masses, and that the fog composition at BYI can be impacted by several different source regions, including the Sea of Japan, Northeastern China, and the East China Sea. Sulfur in the collected fog was highly oxidized: low S(IV concentrations were measured (mean of 2.36 μM in contrast to SO4−2 and in contrast to fog/cloud S(IV concentrations from pollutant source regions; organosulfate species were also observed and were most likely formed through aging of mainly biogenic volatile organic compounds. Low molecular mass organic acids were major contributors to total organic carbon (TOC; 36–69 %, comprising a fraction of TOC at the upper end of that seen in fogs and clouds in other polluted environments. Large contributions were observed from not only acetic and formic acids, but also oxalic, succinic, maleic, and other organic acids that can be produced in aqueous atmospheric organic processing (AAOP reactions. These samples of East Asian fog water containing highly oxidized components represent fog downwind of pollutant sources and can provide new insight into the fate of regional emissions. In particular, these samples demonstrate the result of extensive photochemical aging during multiday transport, including oxidation within wet aerosols and fogs. 10. Fog composition at Baengnyeong Island in the eastern Yellow Sea: detecting markers of aqueous atmospheric oxidations Science.gov (United States) Boris, A. J.; Lee, T.; Park, T.; Choi, J.; Seo, S. J.; Collett, J. L., Jr. 2016-01-01 Samples of fog water were collected at Baengnyeong Island (BYI) in the Yellow Sea during the summer of 2014. The most abundant chemical species in the fog water were NH4+ (mean of 2220 µM), NO3- (1260 µM), SO4-2 (730 µM), and Na+ (551 µM), with substantial contributions from other species consistent with marine and biomass burning influence on some dates. The pH of the samples ranged between 3.48 and 5.00, with a mean of 3.94, intermediate within pH values of fog/cloud water reported previously in Southeast Asia. Back trajectories (72 h) showed that high relative humidity ( > 80 %) was encountered upwind of the sampling site by all but one of the sampled air masses, and that the fog composition at BYI can be impacted by several different source regions, including the Sea of Japan, southeastern China, northeastern China, and the East China Sea. Sulfur in the collected fog was highly oxidized: low S(IV) concentrations were measured (mean of 2.36 µM) in contrast to SO4-2 and in contrast to fog/cloud S(IV) concentrations from pollutant source regions; organosulfate species were also observed and were most likely formed through aging of mainly biogenic volatile organic compounds. Low-molecular-mass organic acids were major contributors to total organic carbon (TOC; 36-69 %), comprising a fraction of TOC at the upper end of that seen in fogs and clouds in other polluted environments. Large contributions were observed from not only acetic and formic acids but also oxalic, succinic, maleic, and other organic acids that can be produced in aqueous atmospheric organic processing (AAOP) reactions. These samples of East Asian fog water containing highly oxidized components represent fog downwind of pollutant sources and can provide new insight into the fate of regional emissions. In particular, these samples demonstrate the result of extensive photochemical aging during multiday transport, including oxidation within wet aerosols and fogs. 11. Fighting global warming by greenhouse gas removal: destroying atmospheric nitrous oxide thanks to synergies between two breakthrough technologies. Science.gov (United States) Ming, Tingzhen; de Richter, Renaud; Shen, Sheng; Caillol, Sylvain 2016-04-01 Even if humans stop discharging CO2 into the atmosphere, the average global temperature will still increase during this century. A lot of research has been devoted to prevent and reduce the amount of carbon dioxide (CO2) emissions in the atmosphere, in order to mitigate the effects of climate change. Carbon capture and sequestration (CCS) is one of the technologies that might help to limit emissions. In complement, direct CO2 removal from the atmosphere has been proposed after the emissions have occurred. But, the removal of all the excess anthropogenic atmospheric CO2 will not be enough, due to the fact that CO2 outgases from the ocean as its solubility is dependent of its atmospheric partial pressure. Bringing back the Earth average surface temperature to pre-industrial levels would require the removal of all previously emitted CO2. Thus, the atmospheric removal of other greenhouse gases is necessary. This article proposes a combination of disrupting techniques to transform nitrous oxide (N2O), the third most important greenhouse gas (GHG) in terms of current radiative forcing, which is harmful for the ozone layer and possesses quite high global warming potential. Although several scientific publications cite "greenhouse gas removal," to our knowledge, it is the first time innovative solutions are proposed to effectively remove N2O or other GHGs from the atmosphere other than CO2. PMID:26805926 12. Fighting global warming by greenhouse gas removal: destroying atmospheric nitrous oxide thanks to synergies between two breakthrough technologies. Science.gov (United States) Ming, Tingzhen; de Richter, Renaud; Shen, Sheng; Caillol, Sylvain 2016-04-01 Even if humans stop discharging CO2 into the atmosphere, the average global temperature will still increase during this century. A lot of research has been devoted to prevent and reduce the amount of carbon dioxide (CO2) emissions in the atmosphere, in order to mitigate the effects of climate change. Carbon capture and sequestration (CCS) is one of the technologies that might help to limit emissions. In complement, direct CO2 removal from the atmosphere has been proposed after the emissions have occurred. But, the removal of all the excess anthropogenic atmospheric CO2 will not be enough, due to the fact that CO2 outgases from the ocean as its solubility is dependent of its atmospheric partial pressure. Bringing back the Earth average surface temperature to pre-industrial levels would require the removal of all previously emitted CO2. Thus, the atmospheric removal of other greenhouse gases is necessary. This article proposes a combination of disrupting techniques to transform nitrous oxide (N2O), the third most important greenhouse gas (GHG) in terms of current radiative forcing, which is harmful for the ozone layer and possesses quite high global warming potential. Although several scientific publications cite "greenhouse gas removal," to our knowledge, it is the first time innovative solutions are proposed to effectively remove N2O or other GHGs from the atmosphere other than CO2. 13. Coarsening of Pd nanoparticles in an oxidizing atmosphere studied by in situ TEM Science.gov (United States) Simonsen, Søren Bredmose; Chorkendorff, Ib; Dahl, Søren; Skoglundh, Magnus; Helveg, Stig 2016-06-01 The coarsening of supported palladium nanoparticles in an oxidizing atmosphere was studied in situ by means of transmission electron microscopy (TEM). Specifically, the Pd nanoparticles were dispersed on a planar and amorphous Al2O3 support and were observed during the exposure to 10 mbar technical air at 650 °C. Time-resolved TEM image series reveal that the Pd nanoparticles were immobile and that a few percent of the nanoparticles grew or shrank, indicating a coarsening process mediated by the Ostwald ripening mechanism. The TEM image contrast suggests that the largest nanoparticles tended to wet the Al2O3 support to a higher degree than the smaller nanoparticles and that the distribution of projected particle sizes consequently broadens by the appearance of an asymmetric tail toward the larger particle sizes. A comparison with computer simulations based on a simple mean-field model for the Ostwald ripening process indicates that the observed change in the particle size distribution can be accounted for by wetting of the Al2O3 support by the larger Pd nanoparticles. 14. Optimizing the electrical excitation of an atmospheric pressure plasma advanced oxidation process. Science.gov (United States) Olszewski, P; Li, J F; Liu, D X; Walsh, J L 2014-08-30 The impact of pulse-modulated generation of atmospheric pressure plasma on the efficiency of organic dye degradation has been investigated. Aqueous samples of methyl orange were exposed to low temperature air plasma and the degradation efficiency was determined by absorbance spectroscopy. The plasma was driven at a constant frequency of 35kHz with a duty cycle of 25%, 50%, 75% and 100%. Relative concentrations of dissolved nitrogen oxides, pH, conductivity and the time evolution of gas phase ozone were measured to identify key parameters responsible for the changes observed in degradation efficiency. The results indicate that pulse modulation significantly improved dye degradation efficiency, with a plasma pulsed at 25% duty showing a two-fold enhancement. Additionally, pulse modulation led to a reduction in the amount of nitrate contamination added to the solution by the plasma. The results clearly demonstrate that optimization of the electrical excitation of the plasma can enhance both degradation efficiency and the final water quality. 15. Effect of atmospheric oxidative plasma treatments on polypropylenic fibers surface: Characterization and reaction mechanisms Energy Technology Data Exchange (ETDEWEB) Nisticò, Roberto, E-mail: roberto.nistico@unito.it [University of Torino, Department of Chemistry and NIS Centre of Excellence, Via P. Giuria 7, 10125 Torino (Italy); Magnacca, Giuliana [University of Torino, Department of Chemistry and NIS Centre of Excellence, Via P. Giuria 7, 10125 Torino (Italy); Faga, Maria Giulia; Gautier, Giovanna [CNR-IMAMOTER, Strada delle Cacce 73, 10135 Torino (Italy); D’Angelo, Domenico; Ciancio, Emanuele [Clean-NT Lab, Environment Park S.p.A., Via Livorno 60, 10144 Torino (Italy); Lamberti, Roberta; Martorana, Selanna [Herniamesh S.r.l., Via F.lli Meliga 1/C, 10034 Chivasso (Italy) 2013-08-15 Atmospheric pressure plasma-dielectric barrier discharge (APP-DBD, open chamber configuration) was used to functionalize polypropylene (PP) fibers surface in order to generate oxidized-reactive groups such as hydroperoxides, alcohols and carbonyl species (i.e. ketones and others). Such a species increased the surface polarity, without causing material degradation. Three different types of plasma mixture (He, He/O{sub 2}, He/O{sub 2}/H{sub 2}O) under three different values of applied power (750, 1050, 1400 W) were investigated. The formed plasma species (O{sub 2}{sup +}, O single atom and OH radical) and their distribution were monitored via optical emission spectrometry (OES) measurements, and the plasma effects on PP surface species formation were followed by X-ray photoemission spectroscopy (XPS). Results allowed to better understand the reaction pathways between plasma phase and PP fibers. In fact, two reaction mechanisms were proposed, the first one concerning the plasma phase reactions and the second one involving material surface modifications. 16. Structural properties of zinc oxide deposited using atmospheric pressure combustion chemical vapour deposition International Nuclear Information System (INIS) In this study the deposition of thin zinc oxide (ZnO) films under atmospheric pressure conditions was investigated. The deposition technique applied was combustion chemical vapour deposition (CCVD), at which a propane–air mixture was combusted in a burner. Dissolved zinc nitrate was used as precursor, which was guided as aerosol droplets by the processing gas flow directly into the reaction zone. Fundamental investigations were performed to form undoped ZnO. The structural properties of the films were analysed in dependence of the substrate temperature during the coating process. The presence of crystalline ZnO structures was proved and differences in film growth and crystallite sizes are revealed. Additionally, the particles generated by the CCVD-flame are characterised. The thin films showed a slight excess of Zn and several states of binding energy could be observed by fitting the core level spectra. Scanning and transmission electron microscopy also indicated ordered structures and additionally different orientations of crystallites were observed. - Highlights: • Columnar growth structures of ZnO by CCVD were observed. • The presence of polycrystalline ZnO with (002) as main orientation was confirmed. • Initial particles significantly differ from crystallite sizes of the resulting films. • The films show an excess of Zn with a Zn-to-O ratio of around 1.7 17. Structural properties of zinc oxide deposited using atmospheric pressure combustion chemical vapour deposition Energy Technology Data Exchange (ETDEWEB) Zunke, I., E-mail: iz@innovent-jena.de [Innovent e.V. Technology Development, Department of Surface Engineering, Prüssingstr. 27B, 07745 Jena (Germany); Wolf, S. [University of Jena, Institute for Solid State Physics, Helmholtzweg 3/5, 07745 Jena (Germany); Heft, A.; Schimanski, A.; Grünler, B. [Innovent e.V. Technology Development, Department of Surface Engineering, Prüssingstr. 27B, 07745 Jena (Germany); Ronning, C.; Seidel, P. [University of Jena, Institute for Solid State Physics, Helmholtzweg 3/5, 07745 Jena (Germany) 2014-08-28 In this study the deposition of thin zinc oxide (ZnO) films under atmospheric pressure conditions was investigated. The deposition technique applied was combustion chemical vapour deposition (CCVD), at which a propane–air mixture was combusted in a burner. Dissolved zinc nitrate was used as precursor, which was guided as aerosol droplets by the processing gas flow directly into the reaction zone. Fundamental investigations were performed to form undoped ZnO. The structural properties of the films were analysed in dependence of the substrate temperature during the coating process. The presence of crystalline ZnO structures was proved and differences in film growth and crystallite sizes are revealed. Additionally, the particles generated by the CCVD-flame are characterised. The thin films showed a slight excess of Zn and several states of binding energy could be observed by fitting the core level spectra. Scanning and transmission electron microscopy also indicated ordered structures and additionally different orientations of crystallites were observed. - Highlights: • Columnar growth structures of ZnO by CCVD were observed. • The presence of polycrystalline ZnO with (002) as main orientation was confirmed. • Initial particles significantly differ from crystallite sizes of the resulting films. • The films show an excess of Zn with a Zn-to-O ratio of around 1.7. 18. Fabrication and electrochemical performance of solid oxide fuel cell components by atmospheric and suspension plasma spray Institute of Scientific and Technical Information of China (English) XIA Wei-sheng; YANG Yun-zhen; ZHANG Hai-ou; WANG Gui-lan 2009-01-01 The theory of functionally graded material (FGM) was applied in the fabrication process of PEN (Positive- Electrolyte-Negative),the core component of solid oxide fuel cell (SOFC).To enhance its electrochemical performance,the functionally graded PEN of planar SOFC was prepared by atmospheric plasma spray (APS).The cross-sectional SEM micrograph and element energy spectrum of the resultant PEN were analyzed.Its interface resistance was also compared with that without the graded layers to investigate the electrochemical performance enhanced by the functionally graded layers.Moreover,a new process,suspension plasma spray (SPS) was applied to preparing the SOFC electrolyte.Higher densification of the coating by SPS,1.61%,is observed,which is helpful to effectively improve its electrical conductivity.The grain size of the electrolyte coating fabricated by SPS is also smaller than that by APS,which is more favourable to obtain the dense electrolyte coatings.To sum up,all mentioned above can prove that the hybrid process of APS and SPS could be a better approach to fabricate the PEN of SOFC stacks,in which APS is for porous electrodes and SPS for dense electrolyte. 19. Torrefaction of agricultural by-products (abstract) Science.gov (United States) Torrefaction of biomass involves heating at 200°C-300°C under inert atmosphere to remove volatiles and produce materials with higher energy values and low moisture. Agricultural by-products, such as apple, grape, olive, and tomato pomaces as well as almond and walnut shells, were torrefied at differ... 20. Multi-scale Model of Residual Strength of 2D Plain Weave C/SiC Composites in Oxidation Atmosphere Science.gov (United States) Chen, Xihui; Sun, Zhigang; Sun, Jianfen; Song, Yingdong 2016-06-01 Multi-scale models play an important role in capturing the nonlinear response of woven carbon fiber reinforced ceramic matrix composites. In plain weave carbon fiber/silicon carbon (C/SiC) composites, the carbon fibers and interphases will be oxidized at elevated temperature and the strength of the composite will be degraded when oxygen enters micro-cracks formed in the as-produced parts due to the mismatch in thermal properties between constituents. As a result of the oxidation on fiber surface, fiber shows a notch-like morphology. In this paper, the change rule of fiber notch depth is fitted by circular function. And a multi-scale model based upon the change rule of fiber notch depth is developed to simulate the residual strength and post-oxidation stress-strain curves of the composite. The multi-scale model is able to accurately predict the residual strength and post-oxidation stress-strain curves of the composite. Besides, the simulated residual strength and post-oxidation stress-strain curves of 2D plain weave C/SiC composites in oxidation atmosphere show good agreements with experimental results. Furthermore, the oxidation time and temperature of the composite are investigated to show their influences upon the residual strength and post-oxidation stress-strain curves of plain weave C/SiC composites. 1. Enhanced Removal of Biogenic Hydrocarbons in Power Plant Plumes Constrains the Dependence of Atmospheric Hydroxyl Concentrations on Nitrogen Oxides Science.gov (United States) De Gouw, J. A.; Trainer, M.; Parrish, D. D.; Brown, S. S.; Edwards, P.; Gilman, J.; Graus, M.; Hanisco, T. F.; Kaiser, J.; Keutsch, F. N.; Kim, S. W.; Lerner, B. M.; Neuman, J. A.; Pollack, I. B.; Roberts, J. M.; Ryerson, T. B.; Veres, P. R.; Warneke, C.; Wolfe, G. 2015-12-01 Hydroxyl (OH) radicals in the atmosphere provide one of the main chemical mechanisms for the removal of trace gases. OH plays a central role in determining the atmospheric lifetime and radiative forcing of greenhouse gases like methane. OH also plays a major role in the oxidation of organic trace gases, which can lead to formation of secondary pollutants such as ozone and PM2.5. Due to its very short atmospheric lifetime of seconds or less, OH concentrations are extremely variable in space and time, which makes measurements and their interpretation very challenging. Several recent measurements have yielded higher than expected OH concentrations. To explain these would require the existence of unidentified, radical recycling processes, but issues with the measurements themselves are also still being discussed. During the NOAA airborne SENEX study in the Southeast U.S., the biogenic hydrocarbons isoprene and monoterpenes were consistently found to have lower mixing ratios in air masses with enhanced nitrogen oxides from power plants. We attribute this to faster oxidation rates of biogenic hydrocarbons due to increased concentrations of OH in the power plant plumes. Measurements at different downwind distances from the Scherer and Harllee Branch coal-fired power plants near Atlanta are used to constrain the dependence of OH on nitrogen oxides. It is found that OH concentrations were highest at nitrogen dioxide concentrations of 1-2 ppbv and decreased at higher and at lower concentrations. These findings agree with the expected dependence of OH on nitrogen oxide concentrations, but do not appear to be consistent with the reports in the literature that have shown high OH concentrations in regions of the atmosphere with high biogenic emissions and low NOx concentrations that would require unidentified radical recycling processes to be explained. 2. The magnetic and oxidation behavior of bare and silica-coated iron oxide nanoparticles synthesized by reverse co-precipitation of ferrous ion (Fe2+) in ambient atmosphere Science.gov (United States) Mahmed, N.; Heczko, O.; Lancok, A.; Hannula, S.-P. 2014-03-01 The synthesis of iron oxide nanoparticles, i.e., magnetite was attempted by using only ferrous ion (Fe2+) as a magnetite precursor, under an ambient atmosphere. The room temperature reverse co-precipitation method was used, by applying two synthesis protocols. The freshly prepared iron oxide was also immediately coated with Stöber silica (SiO2) layer, forming the coreshell structure. The phase, stoichiometry, crystallite and the particle size of the synthesized powders were determined by using X-ray diffraction (XRD) and transmission electron microscope (TEM), while the magnetic and oxidation behaviors were studied by using the vibrating sample magnetometer (VSM) and Mössbauer spectroscopy. Based on the results, the bare iron oxide nanoparticles are in the stoichiometry between the magnetite and the maghemite stoichiometry, i.e., oxidation occurs. This oxidation is depending on the synthesis protocols used. With the silica coating, the oxidation can be prevented, as suggested by the fits of Mössbauer spectra and low temperature magnetic measurement. 3. Corrosion of Iron and Four Commercial Steels in a Cl-Containing Oxidizing Atmosphere at 500～600℃ Institute of Scientific and Technical Information of China (English) Ke ZHANG; Yah NIU; Chaoliu ZENG; Weitao WU 2004-01-01 The corrosion behaviors of Fe and four commercial steels with different Cr contents were investigated in an oxidizing atmosphere containing HCI at 500～600℃, which simulated the environment to which materials are usually exposed in waste incineration. All the test materials underwent an accelerated corrosion in this atmosphere and small amounts of chlorine could be detected at the metal/scale interface. The corrosion mechanism is discussed on the basis of thermodynamic considerations for the reactions between metals and mixed O-CI gases. 4. Standard method for continuous measurement of nitric oxide, nitrogen dioxide, and ozone in the atmosphere. [Calorimetrically using Griess Reagent Energy Technology Data Exchange (ETDEWEB) 1975-01-01 Nitrogen dioxide is absorbed from the atmosphere in a modified Griess reagent which contains 0.5 percent sulfanilic acid and 50 ppM of N-(1-naphthyl)-ethylene diamine hydrochloride in 5 percent acetic acid that produces a red dye. The red dye is measured continuously in a recording colorimeter by comparison with a blank of unreacted reagent. Nitric oxide from the atmosphere passes through the absorber practically unaffected and is oxidized to nitrogen dioxide by bubbling through a dilute permanganate solution prior to determination with modified Griess reagent in a separate cell. Optionally, ozone in the air sample may be determined in a third absorber-colorimeter cell unit by adding about 0.5 to 1.0 ppM of pure nitric oxide to another sample of air and noting the increase in nitrogen dioxide level due to the rapid oxidation of nitric oxide to nitrogen dioxide by ozone. The overall accuracy of the results of the method is +-10 percent. (BLM) 5. Oxidation and nitration of tyrosine by ozone and nitrogen dioxide: reaction mechanisms and biological and atmospheric implications. Science.gov (United States) Sandhiya, L; Kolandaivel, P; Senthilkumar, K 2014-04-01 The nitration of tyrosine by atmospheric oxidants, O3 and NO2, is an important cause for the spread of allergenic diseases. In the present study, the mechanism and pathways for the reaction of tyrosine with the atmospheric oxidants O3 and NO2 are studied using DFT-M06-2X, B3LYP, and B3LYP-D methods with the 6-311+G(d,p) basis set. The energy barrier for the initial oxidation reactions is also calculated at the CCSD(T)/6-31+G(d,p) level of theory. The reaction is studied in gas, aqueous, and lipid media. The initial oxidation of tyrosine by O3 proceeds by H atom abstraction and addition reactions and leads to the formation of six different intermediates. The subsequent nitration reaction is studied for all the intermediates, and the results show that the nitration affects both the side chain and the aromatic ring of tyrosine. The rate constant of the favorable oxidation and nitration reaction is calculated using variational transition state theory over the temperature range of 278-350 K. The spectral properties of the oxidation and nitration products are calculated at the TD-M06-2X/6-311+G(d,p) level of theory. The fate of the tyrosine radical intermediate is studied by its reaction with glutathione antioxidant. This study provides an enhanced understanding of the oxidation and nitration of tyrosine by O3 and NO2 in the context of improving the air quality and reducing the allergic diseases. 6. Exploring Atmospheric Aqueous Chemistry (and Secondary Organic Aerosol Formation) through OH Radical Oxidation Experiments, Droplet Evaporation and Chemical Modeling Science.gov (United States) Turpin, B. J.; Kirkland, J. R.; Lim, Y. B.; Ortiz-Montalvo, D. L.; Sullivan, A.; Häkkinen, S.; Schwier, A. N.; Tan, Y.; McNeill, V. F.; Collett, J. L.; Skog, K.; Keutsch, F. N.; Sareen, N.; Carlton, A. G.; Decesari, S.; Facchini, C. 2013-12-01 Gas phase photochemistry fragments and oxidizes organic emissions, making water-soluble organics ubiquitous in the atmosphere. My group and others have found that several water-soluble compounds react further in the aqueous phase forming low volatility products under atmospherically-relevant conditions (i.e., in clouds, fogs and wet aerosols). Thus, secondary organic aerosol can form as a result of gas followed by aqueous chemistry (aqSOA). We have used aqueous OH radical oxidation experiments coupled with product analysis and chemical modeling to validate and refine the aqueous chemistry of glyoxal, methylglyoxal, glycolaldehyde, and acetic acid. The resulting chemical model has provided insights into the differences between oxidation chemistry in clouds and in wet aerosols. Further, we conducted droplet evaporation experiments to characterize the volatility of the products. Most recently, we have conducted aqueous OH radical oxidation experiments with ambient mixtures of water-soluble gases to identify additional atmospherically-important precursors and products. Specifically, we scrubbed water-soluble gases from the ambient air in the Po Valley, Italy using four mist chambers in parallel, operating at 25-30 L min-1. Aqueous OH radical oxidation experiments and control experiments were conducted with these mixtures (total organic carbon ≈ 100 μM-C). OH radicals (3.5E-2 μM [OH] s-1) were generated by photolyzing H2O2. Precursors and products were characterized using electrospray ionization mass spectrometry (ESI-MS), ion chromatography (IC), IC-ESI-MS, and ultra high resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). Chemical modeling suggests that organic acids (e.g., oxalate, pyruvate, glycolate) are major products of OH radical oxidation at cloud-relevant concentrations, whereas organic radical - radical reactions result in the formation of oligomers in wet aerosols. Products of cloud chemistry and droplet evaporation have 7. Atmospheric oxidation of phenanthrene initiated by OH radicals in the presence of O2 and NOx - A theoretical study. Science.gov (United States) Zhao, Nan; Zhang, Qingzhu; Wang, Wenxing 2016-09-01 Phenanthrene (Phe) is one of the most abundant polycyclic aromatic hydrocarbons (PAHs) observed in polluted urban atmosphere. The most important atmospheric loss process of Phe is the reaction with OH radicals. The present work investigated OH radical-initiated atmospheric degradation of Phe in the presence of O2 and NOx. The possible reaction mechanism was elucidated by density functional theory (DFT) calculations. Calculations show that the main products are a series of ring-retaining and ring-opening oxygenated PAHs containing phenanthrol, phenanthones, phenanthrenequinone, and dialdehydes. Rice-Ramsperger-Kassel-Marcus (RRKM) theory was employed to evaluate the rate constants for the initial steps of Phe with OH. The atmospheric lifetime of Phe relative to gas-phase reactions with OH is estimated to be 4.6h, based on the calculated overall rate constant of 3.02×10(-11)cm(3) molecule(-1)s(-1) at 298K and 1atm. Combined with available experimental data, this work also provides a comprehensive investigation of the formation mechanism of oxygenated PAHs in the atmospheric oxidation process of phenanthrene and should help to clarify its potential health risk. PMID:27169729 8. The atmospheric oxidation of dimethyl, diethyl, and diisopropyl ethers. The role of the intramolecular hydrogen shift in peroxy radicals. Science.gov (United States) Wang, Sainan; Wang, Liming 2016-03-21 The atmospheric oxidation mechanisms of dimethyl ether (DME), diethyl ether (DEE) and diisopropyl ether (DiPE) are studied by using quantum chemistry and unimolecular reaction theory (RRKM-ME) calculations. For the peroxy radical CH3OCH2O2˙ from DME, a barrier height of ∼ 85 kJ mol(-1) is found for its intramolecular H-shift to ˙CH2OCH2OOH, which can recombine rapidly with the atmospheric O2. RRKM-ME calculations obtain an effective rate of ∼ 0.1 s(-1) at 298 K for the formation of ˙O2CH2OCH2OOH. For similar radicals in DEE and DiPE, effective rates are 1.6 s(-1) and 1.1 s(-1), respectively. In the atmosphere, these unimolecular reactions are fast enough to compete with the bimolecular reactions with NO and/or HO2, especially when [NO] is low. The fates of radicals after the H-shifts are also examined here. Several subsequent reactions are found to recycle OH radicals. New mechanisms are proposed on the basis of present calculations and are consistent with previous experimental results. In the atmosphere, the routes via H-shifts represent an auto-oxidation of these ethers with no involvement of NOx and therefore no O3 formation, and also a self-cleaning mechanism of organic compounds due to recycling of OH radicals. Some of the end products are highly oxidized with multifunctional groups and high O : C ratios, suggesting their low volatility and potential contribution to secondary organic aerosols. PMID:26907474 9. Characteristic of coal combustion in oxygen/carbon dioxide atmosphere and nitric oxide release during this process International Nuclear Information System (INIS) Combustion characteristic of a bituminous coal and an anthracite coal in oxygen/carbon dioxide (O2/CO2) atmosphere is investigated in a thermogravimetric (TG) analyzer. The characteristic parameters, which are deduced from the TG-DTG (differential thermogravimetric) curves, show that the coal combustion process is basically kept consistent in O2/CO2 and O2/N2 atmosphere at the O2 concentration of 20%. The Coats-Redfern method with the reaction order of 1.25 could perfectly describe the combustion process in these two different atmospheres through the calculation of the kinetic parameters for the two coals. Nitric oxide (NO) release is concentrated in a narrower time period in O2/CO2 atmosphere compared with the one in O2/N2 atmosphere during the coal combustion process. Though the high value of the NO release rate peak, the total conversion of the fuel-N to NO is strongly depressed in O2/CO2 atmosphere, and at 1473 K, the conversion is reduced by 28.99% for the bituminous coal and 22.54% for the anthracite coal, respectively. When O2 concentration is increased from 20% to 40% in O2/CO2 atmosphere, the coal combustion property is obviously improved with the shift of the whole process into the lower temperature zone and the more intensive of the reaction occurrence in a narrower temperature range. However, the total fuel-N to NO conversion is increased accordingly. For bituminous coal the increase is 17.22% at 1073 K and 20.51% at 1173 K, and for anthracite coal the increase is 15.73% at 1073 K and 16.19% at 1173 K. 10. High throughput measurement of high temperature strength of ceramics in controlled atmosphere and its use on solid oxide fuel cell anode supports DEFF Research Database (Denmark) Frandsen, Henrik Lund; Curran, Declan; Rasmussen, Steffen; 2014-01-01 In the development of structural and functional ceramics for high temperature electrochemical conversion devices such as solid oxide fuel cells, their mechanical properties must be tested at operational conditions, i.e. at high temperature and controlled atmospheres. Furthermore, characterization... 11. Oxidant Component In The Martian Atmosphere Observed By Mex/pfs Science.gov (United States) Kasaba, Yasumasa; Aoki, S.; Nakagawa, H.; Murata, I.; Formisano, V.; Giuranna, M.; Geminale, A. 2010-10-01 Previous observations have been suggested that the large and fast variations of methane in the Martian atmosphere would be caused by oxidation loss with H2O2. These results also suggested that H2O2 would be produced in quantities much larger than foreseen by water photochemistry during dust storms and dust devils by means of electrostatic charging of the dust grains. However, past ground-based observations of H2O2 mixing ratios were few and contradictory with photochemical model. In this study, we tried to detect the Martian H2O2 from the continuous observations with Planetary Fourier Spectroscopy (PFS) onboard Mars Express (MEX) over several Mars years. Based on the possible H2O2 line at 362 cm-1 which is not contaminated by strong water lines, the derived H2O2 mixing ratio shows varies between 0 and 50 ppb with an average and standard deviation of 20-30 ppb, respectively. The result itself is good consistent with the photochemical model. However, the credibility of this innovative result shall be established. We tried to evaluate the results with the one in other lines at 379, 416 and 433 cm-1. At the moment, the results from these four lines are inconsistent. In order to clarify the true absorption of H2O2, the following two things are tried: (1) The removal of the side lobe effects in the instrumental function (i.e. Adoption of the apodization into the interferogram analysis.) (2) Identification of the artificial enhancement at the H2O2 absorption lines (i.e., the H2O2 absorption in the condition with very low H2O mixing ratio. Less absorption shall be expected in average.). This paper will reflects the updated results based this trials. In addition, we will also briefly report our recent ground-based activities, i.e., (1) submm observations of Martian minor elements and (2) the development of infrared heterodyne spectrometer. 12. Preparation of Superfine Transparent Iron Oxide with Ferrous Sulphate from the By-product of Titanium Dioxide Production%钛白副产硫酸亚铁制备超细透明氧化铁黄研究 Institute of Scientific and Technical Information of China (English) 李金磊; 胡兵; 宋建民 2012-01-01 以钛白粉厂副产物硫酸亚铁为原料,以氨水为沉淀剂,采用空气氧化法制备超细透明氧化铁黄.分别研究了影响晶种形成和晶体生长的主要影响因素.通过优化实验,得出了最佳工艺条件.晶种制备阶段：温度为30℃,空气流量为2L/min,溶液的pH为4～6,搅拌速度为400r/min,Fe2＋浓度为1mol/L.晶体生长阶段：温度为85℃,空气流量为2L/min,溶液pH为4～6.%A process of preparing superfine transparent iron oxide with the by-products of ferrous sulfate was described.The process included two steps：the yielding and growing of crystals.Several key factors affecting the two steps were studied respectively such as effects of Fe2＋ concentration,air flow rate and stirring rate and reaction temperature and pH values. 13. Were ancient granitoid compositions influenced by contemporaneous atmospheric and hydrosphere oxidation states?Were ancient granitoid compositions influenced by contemporaneous atmospheric and hydrosphere oxidation states? Science.gov (United States) Jagoutz, Oliver 2014-05-01 A fundamental shift in the nature of granitoids occurs at approximately the Archean-Proterozoic boundary. Archean crust is dominated Na-rich tonalite-trondhjemite-granodiorites (TTGs), whereas post-Archean granitoids are characterized by K-rich granodiorite-granite (GG). Due to the HREE depletion commonly found in TTGs indicating the presence of residual garnet, many researchers have proposed that the difference in Na/K is related to the deeper melting depth of the TTG parental liquids. Here I present a compilation of the relevant experimental data, documenting that no correlation exists between the Na/K of derivative felsic liquids and the pressure of partial melting/fractional crystallization. Instead, the Na/K ratio of the felsic liquid best correlates with the Na/K ratio of the source. This implies that in Archean time the source material of TTG rocks must have been Na/K enriched relative to the modern. Modern granitoids are dominantly formed in a supra subduction zone environment, where a feedback loop exists between subducted materials (oceanic crust and sediments) and arc magmatism. Sea-floor weathering and the Na/K of the altered oceanic crust strongly depends on f(O2) conditions during alteration, which likely changed with earth history. During alteration under oxidized condition K2O is fixated due to the formation of celadonite (K-Mica), wheres during anoxic condition saponite (Na-Smectite) is the stable alteration mineral. I propose that the rise of oxygen at 2600-2400 Ma triggered associated changes in f(O2) seafloor alteration conditions. The change in the dominant seafloor alteration mineral from reduced to oxidized causes a change in the nature of the arc magma source and provides a possible explanation for the observed transition from TTGrocks in the Archean to the GG-granitoids in post-Archean times. 14. Oxidation of atmospheric methane in Northern European soils, comparison with other ecosystems, and uncertainties in the global terrestrial sink DEFF Research Database (Denmark) Smith, K.A.; Dobbie, K.E.; Ball, B.C.; 2000-01-01 , with a log-normal distribution (log-mean ˜ 1.6 kg CH4 ha-1 y-1). Conversion of natural soils to agriculture reduced oxidation rates by two-thirds -- closely similar to results reported for other regions. N inputs also decreased oxidation rates. Full recovery of rates after these disturbances takes > 100 y......This paper reports the range and statistical distribution of oxidation rates of atmospheric CH4 in soils found in Northern Europe in an international study, and compares them with published data for various other ecosystems. It reassesses the size, and the uncertainty in, the global terrestrial CH4...... sink, and examines the effect of land-use change and other factors on the oxidation rate. Only soils with a very high water table were sources of CH4; all others were sinks. Oxidation rates varied from 1 to nearly 200 µg CH4 m-2 h-1; annual rates for sites measured for =1 y were 0.1-9.1 kg CH4 ha-1 y-1... 15. 3-D laser confocal microscopy study of the oxidation of NdFeB magnets in atmospheric conditions Science.gov (United States) Meakin, J. P.; Speight, J. D.; Sheridan, R. S.; Bradshaw, A.; Harris, I. R.; Williams, A. J.; Walton, A. 2016-08-01 Neodymium iron boron (NdFeB) magnets are used in a number of important applications, such as generators in gearless wind turbines, motors in electric vehicles and electronic goods (e.g.- computer hard disk drives, HDD). Hydrogen can be used as a processing gas to separate and recycle scrap sintered Nd-Fe-B magnets from end-of-life products to form a powder suitable for recycling. However, the magnets are likely to have been exposed to atmospheric conditions prior to processing, and any oxidation could lead to activation problems for the hydrogen decrepitation reaction. Many previous studies on the oxidation of NdFeB magnets have been performed at elevated temperatures; however, few studies have been formed under atmospheric conditions. In this paper a combination of 3-D laser confocal microscopy and Raman spectroscopy have been used to assess the composition, morphology and rate of oxidation/corrosion on scrap sintered NdFeB magnets. Confocal microscopy has been employed to measure the growth of surface reaction products at room temperature, immediately after exposure to air. The results showed that there was a significant height increase at the triple junctions of the Nd-rich grain boundaries. Using Raman spectroscopy, the product was shown to consist of Nd2O3 and formed only on the Nd-rich triple junctions. The diffusion coefficient of the triple junction reaction product growth at 20 °C was determined to be approximately 4 × 10-13 cm2/sec. This value is several orders of magnitude larger than values derived from the diffusion controlled oxide growth observations at elevated temperatures in the literature. This indicates that the growth of the room temperature oxidation products are likely defect enhanced processes at the NdFeB triple junctions. 16. The effects of re-firing process under oxidizing atmosphere and temperatures on the properties of strontium aluminate phosphors Energy Technology Data Exchange (ETDEWEB) Karacaoglu, Erkul, E-mail: erkaracaoglu@gmail.com [Anadolu University, Graduate School of Sciences, Department of Materials Science and Engineering, Eskisehir (Turkey); Fosfortek Phosphor Technologies Co., Eskisehir (Turkey); Karasu, Bekir [Anadolu University, Materials Science and Engineering Department, Eskisehir (Turkey) 2013-10-15 Graphical abstract: The comparative emission spectra of standard and re-fired Phosphor A under oxidizing atmosphere at various temperatures. The colour of Phosphor A re-fired at higher temperatures above 900 °C shifted from yellowish-green to bluish-green in the dark. But, the bluish-green emission could only be seen when it was exposed to UV and disappeared as soon as the light source was removed. Moreover, the emission intensities decreased as the re-firing temperatures increased. This could be attributed to the oxidation of Eu{sup 2+} during the re-firing process. It is well known fact from the literature that the reduction of Eu{sup 3+} to Eu{sup 2+} in appropriate host materials needs an annealing process in a reducing atmosphere such as H{sub 2}, H{sub 2}/N{sub 2} mixture or CO. Up to now, the reduction phenomena of Eu{sup 3+} → Eu{sup 2+} in air have been found in phosphates (Ba{sub 3}(PO{sub 4}){sub 2}:Eu), sulphates (BaSO{sub 4}:Eu), borates (SrB{sub 4}O{sub 7}:Eu, SrB{sub 6}O{sub 10}:Eu and BaB{sub 8}O{sub 13}:Eu) and aluminates (Sr{sub 4}Al{sub 14}O{sub 25}:Eu). Interestingly, an apparent blue shift in the phosphorescence spectrum was observed in the samples re-fired at 1000 °C and above, indicating a minimal effect on the oxidation state or the electronic energy levels of the co-doped Dy{sup 3+} ions, which were thought to act as long-lived hole traps resulting in long afterglow. - Highlights: • This study examines the effects re-firing at oxidizing atmosphere of photoluminescence of three different commercial SrAl{sub 2}O{sub 4}:Eu{sup 2+},Dy{sup 3+}-phosphors. • All the commercial SrAl{sub 2}O{sub 4}:Eu{sup 2+},Dy{sup 3+}-phosphors completely lost their phosphorescence after being re-fired at 1300 °C. • Oxidizing environment and re-firing temperature naturally affecting the valance of Eu{sup 2+} may cause the basic lattice structure to be modified and also limit their applications at higher temperatures, such as third firing vetrosa d 17. Determination of carbon in amorphous carbon and uranium monocarbide by oxidation with lead(IV) oxide, copper(II) oxide or barium sulfate in an inert atmosphere International Nuclear Information System (INIS) Oxidation behavior was studied on amorphous carbon and carbon in uranium monocarbide when lead(IV) oxide, copper(II) oxide and barium sulfate were used as the oxidizing fluxes in helium. The amorphous carbon and the carbon in the carbide were completely extracted with lead oxide in 5 min at 10000C and in 8 min at 700 and 5000C, respectively. Carbon in two samples was quantitatively extracted at 10000C with copper oxide in 8 and 5 min, and with barium sulfate in 7 and 5 min, respectively. The rate of extraction of carbon with copper oxide decreased with decreasing temperature. It was found that the mixing ratio of the oxidizing flux to the amorphous carbon or carbide gave effect on the recovery of carbon. The conventional capillary-trap method which is used for the determination of carbon has a disadvantage that, when carbon dioxide is caught in a cold trap (liquid nitrogen), oxygen is also trapped. This disadvantage was eliminated when a stream of helium was used in place of oxygen. Carbon in the sample can be determined with lead oxide, copper oxide or barium sulfate by extracting carbon dioxide at 10000C for 10 min. (auth.) 18. Oxidation characteristics of nickel-base superalloys at high temperature in air and helium atmospheres International Nuclear Information System (INIS) Nickel-base superalloys are considered as materials for piping and structural materials in a very high temperature gas cooled reactor (VHTR). They are subjected to the environmental degradation caused by a continuous process for oxidation due to small amount of impurities in He coolant during long term operation. In the present study, the oxidation behaviors of several nickel-base superalloys such as Alloy-617, Haynes-214 and Haynes-230 in particular, were studied at the temperature of 900 and 1100 C degrees in air, and in the high purity He environment. Oxide layers were analyzed by SEM (Scanning Electron Microscope) and EDX (Energy Dispersive X-ray analysis). The differences in oxidation behaviors of these alloys were mainly caused by different protective oxide layers on surface. In the case of Alloy-617 and Haynes-230, Cr2O3 layer formed on the surface which is not stable at 1100 C degrees. Therefore, the weight increased significantly due to oxidation at the initial stage, which followed by a decrease due to the scaling and volatilization of Cr2O3 layer. On the other hand, since Haynes-214 has mainly Al2O3 oxide layer on surface which is more stable and has more dense structure at higher temperature, the weight gain eventually reaches to parabolic. Microstructural characteristics of internal carbides and carbide depletion zone were analyzed. With oxidation time, continuous grain boundary carbides of M23C6 type were getting thin or it disappeared partially. Especially, carbides on grain boundary disappeared entirely below oxide layer (carbide depletion zone). It was getting wide with oxidation time. For Haynes-214, the size of carbide depletion zone was smaller than other alloys because Al2O3 layer acted as a diffusion layer prevented effectively the penetration of oxygen into base metal. (authors) 19. SCR atmosphere induced reduction of oxidized mercury over CuO-CeO2/TiO2 catalyst. Science.gov (United States) Li, Hailong; Wu, Shaokang; Wu, Chang-Yu; Wang, Jun; Li, Liqing; Shih, Kaimin 2015-06-16 CuO-CeO2/TiO2 (CuCeTi) catalyst synthesized by a sol-gel method was employed to investigate mercury conversion under a selective catalytic reduction (SCR) atmosphere (NO, NH3 plus O2). Neither NO nor NH3 individually exhibited an inhibitive effect on elemental mercury (Hg(0)) conversion in the presence of O2. However, Hg(0) conversion over the CuCeTi catalyst was greatly inhibited under SCR atmosphere. Systematic experiments were designed to investigate the inconsistency and explore the in-depth mechanisms. The results show that the copresence of NO and NH3 induced reduction of oxidized mercury (Hg(2+), HgO in this study), which offset the effect of catalytic Hg(0) oxidation, and hence resulted in deactivation of Hg(0) conversion. High NO and NH3 concentrations with a NO/NH3 ratio of 1.0 facilitated Hg(2+) reduction and therefore lowered Hg(0) conversion. Hg(2+) reduction over the CuCeTi catalyst was proposed to follow two possible mechanisms: (1) direct reaction, in which NO and NH3 react directly with HgO to form N2 and Hg(0); (2) indirect reaction, in which the SCR reaction consumed active surface oxygen on the CuCeTi catalyst, and reduced species on the CuCeTi catalyst surface such as Cu2O and Ce2O3 robbed oxygen from adjacent HgO. Different from the conventionally considered mechanisms, that is, competitive adsorption responsible for deactivation of Hg(0) conversion, this study reveals that oxidized mercury can transform into Hg(0) under SCR atmosphere. Such knowledge is of fundamental importance in developing efficient and economical mercury control technologies for coal-fired power plants. PMID:25961487 20. Modelling atmospheric oxidation of 2-aminoethanol (MEA) emitted from post-combustion capture using WRF-Chem. Science.gov (United States) Karl, M; Svendby, T; Walker, S-E; Velken, A S; Castell, N; Solberg, S 2015-09-15 Carbon capture and storage (CCS) is a technological solution that can reduce the amount of carbon dioxide (CO2) emissions from the use of fossil fuel in power plants and other industries. A leading method today is amine based post-combustion capture, in which 2-aminoethanol (MEA) is one of the most studied absorption solvents. In this process, amines are released to the atmosphere through evaporation and entrainment from the CO2 absorber column. Modelling is a key instrument for simulating the atmospheric dispersion and chemical transformation of MEA, and for projections of ground-level air concentrations and deposition rates. In this study, the Weather Research and Forecasting model inline coupled with chemistry, WRF-Chem, was applied to quantify the impact of using a comprehensive MEA photo-oxidation sequence compared to using a simplified MEA scheme. Main discrepancies were found for iminoethanol (roughly doubled in the detailed scheme) and 2-nitro aminoethanol, short MEA-nitramine (reduced by factor of two in the detailed scheme). The study indicates that MEA emissions from a full-scale capture plant can modify regional background levels of isocyanic acid. Predicted atmospheric concentrations of isocyanic acid were however below the limit value of 1 ppbv for ambient exposure. The dependence of the formation of hazardous compounds in the OH-initiated oxidation of MEA on ambient level of nitrogen oxides (NOx) was studied in a scenario without NOx emissions from a refinery area in the vicinity of the capture plant. Hourly MEA-nitramine peak concentrations higher than 40 pg m(-3) did only occur when NOx mixing ratios were above 2 ppbv. Therefore, the spatial variability and temporal variability of levels of OH and NOx need to be taken into account in the health risk assessment. The health risk due to direct emissions of nitrosamines and nitramines from full-scale CO2 capture should be investigated in future studies. PMID:25958366 1. SCR atmosphere induced reduction of oxidized mercury over CuO-CeO2/TiO2 catalyst. Science.gov (United States) Li, Hailong; Wu, Shaokang; Wu, Chang-Yu; Wang, Jun; Li, Liqing; Shih, Kaimin 2015-06-16 CuO-CeO2/TiO2 (CuCeTi) catalyst synthesized by a sol-gel method was employed to investigate mercury conversion under a selective catalytic reduction (SCR) atmosphere (NO, NH3 plus O2). Neither NO nor NH3 individually exhibited an inhibitive effect on elemental mercury (Hg(0)) conversion in the presence of O2. However, Hg(0) conversion over the CuCeTi catalyst was greatly inhibited under SCR atmosphere. Systematic experiments were designed to investigate the inconsistency and explore the in-depth mechanisms. The results show that the copresence of NO and NH3 induced reduction of oxidized mercury (Hg(2+), HgO in this study), which offset the effect of catalytic Hg(0) oxidation, and hence resulted in deactivation of Hg(0) conversion. High NO and NH3 concentrations with a NO/NH3 ratio of 1.0 facilitated Hg(2+) reduction and therefore lowered Hg(0) conversion. Hg(2+) reduction over the CuCeTi catalyst was proposed to follow two possible mechanisms: (1) direct reaction, in which NO and NH3 react directly with HgO to form N2 and Hg(0); (2) indirect reaction, in which the SCR reaction consumed active surface oxygen on the CuCeTi catalyst, and reduced species on the CuCeTi catalyst surface such as Cu2O and Ce2O3 robbed oxygen from adjacent HgO. Different from the conventionally considered mechanisms, that is, competitive adsorption responsible for deactivation of Hg(0) conversion, this study reveals that oxidized mercury can transform into Hg(0) under SCR atmosphere. Such knowledge is of fundamental importance in developing efficient and economical mercury control technologies for coal-fired power plants. 2. Site variation in methane oxidation as affected by atmospheric deposition and type of temperate forest ecosystem Science.gov (United States) Brumme, Rainer; Borken, Werner 1999-06-01 Factors controlling methane oxidation were analyzed along a soil acidity gradient (pH(H2O) 3.9 to 5.2) under beech and spruce forests in Germany. Mean annual methane oxidation ranged from 0.1 to 2.5 kg CH4 ha-1 yr-1 and was correlated with base saturation (r2 = 0.88), soil pH (r2 = 0.77), total nitrogen (r2 = 0.71), amount of the organic surface horizon (r2 = 0.49) and bulk density of the mineral soil (r2 = 0.43). At lower pHs the formation of an organic surface horizon was promoted. This horizon did not have any methane oxidation capacity and acted like a gas diffusion barrier, which decreased the methane oxidation capacity of the soil. In contrast, on sites at the higher end of the pH range, higher burrowing activity of earthworms increased macroporosity and thereby gas diffusivity and methane oxidation. Gas diffusivity was also affected by litter shape: broad beech leaves reduced methane oxidation more than spruce needles. An increase in methane oxidation of most soil samples following sieving indicates that diffusion is the main limiting factor for methane oxidation. However, this "sieving effect" was less in soils with a pH below 5 than in soils with a pH above 5, which we attribute to a direct effect of soil acidity. We discuss our results using a hierarchical concept for the "short-term" and "long-term" controls on methane oxidation in forest ecosystems. 3. Synergy of CuO and CeO2 combination for mercury oxidation under low-temperature selective catalytic reduction atmosphere KAUST Repository Li, Hailong 2016-07-19 Synergy for low temperature Hg0 oxidation under selective catalytic reduction (SCR) atmosphere was achieved when copper oxides and cerium oxides were combined in a CuO-CeO2/TiO2 (CuCeTi) catalyst. Hg0 oxidation efficiency as high as 99.0% was observed on the CuCeTi catalyst at 200 °C, even the gas hourly space velocity was extremely high. To analyze the synergistic effect, comparisons of catalyst performance in the presence of different SCR reaction gases were systematically conducted over CuO/TiO2 (CuTi), CeO2/TiO2 (CeTi) and CuCeTi catalysts prepared by sol-gel method. The interactions between copper oxides and cerium oxides in CuCeTi catalyst yielded more surface chemisorbed oxygen, and facilitated the conversion of gas-phase O2 to surface oxygen, which are favorable for Hg0 oxidation. Copper oxides in the combination interacted with NO forming more chemisorbed oxygen for Hg0 oxidation in the absence of gas-phase O2. Cerium oxides in the combination promoted Hg0 oxidation through enhancing the transformations of NO to NO2. In the absence of NO, NH3 exhibited no inhibitive effect on Hg0 oxidation, because enough Lewis acid sites due to the combination of copper oxides and cerium oxides scavenged the competitive adsorption between NH3 and Hg0. In the presence of NO, although NH3 lowered Hg0 oxidation rate through inducing reduction of oxidized mercury, complete recovery of Hg0 oxidation activity over the CuCeTi catalyst was quickly achieved after cutting off NH3. This study revealed the synergistic effect of the combination of copper oxides and cerium oxides on Hg0 oxidation, and explored the involved mechanisms. Such knowledge would help obtaining maximum Hg0 oxidation co-benefit from SCR units in coal-fired power plants. 4. Biomass torrefaction characteristics in inert and oxidative atmospheres at various superficial velocities. Science.gov (United States) Chen, Wei-Hsin; Lu, Ke-Miao; Liu, Shih-Hsien; Tsai, Chi-Ming; Lee, Wen-Jhy; Lin, Ta-Chang 2013-10-01 The reaction characteristics of four biomass materials (i.e. oil palm fiber, coconut fiber, eucalyptus, and Cryptomeria japonica) with non-oxidative and oxidative torrefaction at various superficial velocities are investigated where nitrogen and air are used as carrier gases. Three torrefaction temperatures of 250, 300, and 350 °C are considered. At a given temperature, the solid yield of biomass is not affected by N2 superficial velocity, revealing that the thermal degradation is controlled by heat and mass transfer in biomass. Increasing air superficial velocity decreases the solid yield, especially in oil palm fiber and coconut fiber, implying that the torrefaction reaction of biomass is dominated by surface oxidation. There exists an upper limit of air superficial velocity in the decrement of solid yield, suggesting that beyond this limit the thermal degradation of biomass is no longer governed by surface oxidation, but rather is controlled by internal mass transport. 5. Total atmospheric deposition of oxidized nitrogen in the United States Pacific Northwest for 2002 Data.gov (United States) U.S. Geological Survey, Department of the Interior — This spatial data set was created by the U.S. Geological Survey (USGS) to represent the amount of wet and dry deposition of oxidized nitrogen in the Pacific... 6. Total atmospheric deposition of oxidized and reduced nitrogen in the United States Pacific Northwest for 2002 Data.gov (United States) U.S. Geological Survey, Department of the Interior — This spatial data set was created by the U.S. Geological Survey (USGS) to represent the amount of wet and dry deposition of oxidized and reduced nitrogen in the... 7. Using sulfur isotope fractionation to understand the atmospheric oxidation of SO 2 OpenAIRE Harris, Eliza 2012-01-01 Sulfate aerosol plays an important but uncertain role in cloud formation and radiative forcing of the climate, and is also important for acid deposition and human health. The oxidation of SO2 to sulfate is a key reaction in determining the impact of sulfate in the environment through its effect on aerosol size distribution and composition. This thesis presents a laboratory investigation of sulfur isotope fractionation during SO2 oxidation by the most important gas-phase and heterogeneous path... 8. Protection of articles in oxidizing atmosphere on high-temperature heating International Nuclear Information System (INIS) Composition of the melt on the base of potassium or sodium bichromates with oxygen-containing molybdenum compounds is developed for the treatment of steel blanks to form scale-resistant oxide layer. Tubes pressed out of the blanks, covered with oxide layer, are characterized by the increased accuracy of dimensions and improved quality of the surface. Besides, application of protection layer increases the instrument endurance 9. High-throughput processes for industrially scalable deposition of zinc oxide at atmospheric pressure NARCIS (Netherlands) Illiberi, A.; Grob, F.; Kniknie, B.; Frijters, C.; Deelen, J. van; Poodt, P.; Beckers, E.H.A.; Bolt, P.J. 2014-01-01 ZnO films have been grown on a moving glass substrate by high temperature (480 0C) chemical vapour deposition (CVD) and low temperature (200 0C) plasma enhanced CVD (PE-CVD) process at atmospheric pressure. Deposition rates above 7 nm/s have been achieved for substrate speeds from 20 to 500 mm/min. 10. Nanostructured europium oxide thin films deposited by pulsed laser ablation of a metallic target in a He buffer atmosphere Energy Technology Data Exchange (ETDEWEB) Luna, H.; Franceschini, D. F.; Prioli, R.; Guimaraes, R. B.; Sanchez, C. M.; Canal, G. P.; Barbosa, M. D. L.; Galvao, R. M. O. [Instituto de Fisica, Universidade Federal do Rio de Janeiro, Cx. Postal 68528, Rio de Janeiro, RJ 21941-972 (Brazil); Instituto de Fisica, Universidade Federal Fluminense, Niteroi, RJ 24210-346 (Brazil); Departamento de Fisica, Pontificia Universidade Catolica do Rio de Janeiro, Rua Marques de Sao Vicente 225, 22453-970, Rio de Janeiro, RJ (Brazil); Instituto de Fisica, Universidade Federal Fluminense, Niteroi, RJ 24210-346 (Brazil); Centro Brasileiro de Pesquisas Fisicas, Laboratorio de Plasmas Aplicados, Rua Xavier Sigaud 150, 22290-180, Rio de Janeiro, RJ (Brazil); Instituto de Fisica, Departamento de Fisica Nuclear, Universidade de Sao Paulo, Caixa Postal 66328, 05315-970, Sao Paulo, SP (Brazil); Centro Brasileiro de Pesquisas Fisicas, Laboratorio de Plasmas Aplicados, Rua Xavier Sigaud 150, 22290-180, Rio de Janeiro, RJ (Brazil) 2010-09-15 Nanostrucured europium oxide and hydroxide films were obtained by pulsed Nd:YAG (532 nm) laser ablation of a europium metallic target, in the presence of a 1 mbar helium buffer atmosphere. Both the produced film and the ambient plasma were characterized. The plasma was monitored by an electrostatic probe, for plume expansion in vacuum or in the presence of the buffer atmosphere. The time evolution of the ion saturation current was obtained for several probe to substrate distances. The results show the splitting of the plume into two velocity groups, being the lower velocity profile associated with metal cluster formation within the plume. The films were obtained in the presence of helium atmosphere, for several target-to-substrate distances. They were analyzed by Rutherford backscattering spectrometry, x-ray diffraction, and atomic force microscopy, for as-deposited and 600 deg. C treated-in-air samples. The results show that the as-deposited samples are amorphous and have chemical composition compatible with europium hydroxide. The thermally treated samples show x-ray diffraction peaks of Eu{sub 2}O{sub 3}, with chemical composition showing excess oxygen. Film nanostructuring was shown to be strongly correlated with cluster formation, as shown by velocity splitting in probe current versus time plots. 11. Mechanism and kinetic properties of OH-initiated atmospheric oxidation degradation of methamidophos in the presence of O2/NO Science.gov (United States) Shi, Xiangli; Zhang, Ruiming; Zhang, Qingzhu; Wang, Wenxing 2016-05-01 Methamidophos is a member of the organophosphorus insecticides. In the present work, the mechanism of the OH radical-initiated atmospheric oxidation degradation of methamidophos and the possible degradation products were investigated with the aid of quantum chemical calculations. The geometrical parameters and vibrational frequencies were calculated at the MPWB1K/6-31+G(d,p) level. The energies of all the stationary points were carried out at the MPWB1K/6-311+G(3df,2p) level of theory. The rate constants of key elementary steps involved in the OH radical-initiated atmospheric degradation of methamidophos were calculated by meaning of the canonical variation transition-state (CVT) theory with the small curvature tunneling (SCT) correction over the possible atmospheric temperature range of 273-333 K. The rate-temperature formulas were fitted for the first time. The pre-exponential factor and the activation energy were obtained. Studies show that the OH additions from the trans-positions of the NH2 and OCH3 groups, the H abstractions from the SCH3 and OCH3 groups as well as the substitution reaction resulting in the products of CH3OP(O)OHNH2 and SCH3 are thermodynamically favorable reaction pathways for the reaction of methamidophos with OH radicals due to the low barrier and strong exothermicity. 12. Atmospheric oxygen levels, anaerobic methane oxidation, and the coupling of the global COS cycles by sulfate reduction Science.gov (United States) Wortmann, U. G.; Chernyavsky, B. M. 2007-12-01 Changes in the partitioning between the reduced and oxidized reservoirs of carbon and sulfur are the dominant control on atmospheric oxygen levels, and the partitioning itself depends to a large degree on microbial redox processes remineralizing organic matter (OM). However, the controls of organic matter preservation in marine sediments are one of the most complex and controversial issues in contemporary biochemistry. Knowledge how the transition from one electron acceptor to another affects OM remineralization rates is scant even for the transition from aerobic to anaerobic respiration. Much less is known about the transition from anaerobic respiration to fermentation. Although the individual pathways of methane generation are known, our understanding of the complex interactions between different bacterial groups remains limited, resulting in considerable difficulties to resolve these questions in microcosm experiments. Here we show that a dramatic drop in seawater sulfate concentrations during the Early Cretaceous (Wortmann & Chernyavsky, Nature 2007) resulted in a global breakdown of microbial sulfate reduction in the marine subsurface biosphere. This event resulted in a positive excursion of the global δ13C-value, suggesting that organic matter remineralization rates dropped by more than 50%. This implies that the methanogenic microbial community was unable to increase their metabolic rates, despite the increased supply of organic matter. the reduced availability of sulfate for anaerobic methane oxidation did not increase the flux of isotopically light carbon into the ocean/atmosphere system. We therefore speculate that the capacity of marine methanogenic ecosystems to synthesize extracellular enzymes to hydrolyze organic matter is specific to the prevailing type of organic matter. This results in a positive coupling of the metabolic activity of both ecosystems, which in turn is a necessary prerequisite to decouple reduced carbon and sulfur burial, a key 13. Sensitivity of measured steam oxidation kinetics to atmospheric control and impurities Science.gov (United States) Sooby Wood, E.; Terrani, K. A.; Nelson, A. T. 2016-08-01 The most direct means of improving the ability of water cooled reactors to withstand excessive cladding oxidation during a loss of coolant accident is to either modify or replace zirconium cladding. It is important to understand what level of agreement is to be expected as a function of systematic differences in steam oxidation testing techniques and instrumentation among testing facilities. The present study was designed to assess the sensitivities of some of the current and proposed reactor cladding materials. Steam oxidation sensitivity of Zircaloy-2, FeCrAl and Mo to O2 impurities in steam were examined. It was shown that the effect of O2 impurities is negligible for the two former materials while significant in the case of Mo. 14. An evaluation of anti-oxidative protection for cells against atmospheric pressure cold plasma treatment Energy Technology Data Exchange (ETDEWEB) Ma Ruonan; Zhang Qian [Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); Feng Hongqing; Liang Yongdong [College of Engineering, Peking University, Beijing 100871 (China); Li Fangting [Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); College of Physics, Peking University, Beijing 100871 (China); Zhu Weidong [Department of Applied Science and Technology, Saint Peter' s College, Jersey City, New Jersey 07306 (United States); Zhang Jue; Fang Jing [Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); College of Engineering, Peking University, Beijing 100871 (China); Becker, Kurt H. [Department of Applied Physics, Polytechnic Institute of New York University, Brooklyn, New York 11201 (United States) 2012-03-19 With the development of plasma medicine, safety issues are emerging as a serious concern. In this study, both intracellular (genetic engineering) and extracellular (scavengers) measures were tested in an effort to determine the best protection for cells against plasma-induced oxidative stress. All results of immediate reactive species detection, short term survival and long term proliferation, suggest that intracellular pathways are superior in reducing oxidative stress and cell death. This work provides a potential mechanism to enhance safety and identifies precautionary measures that should be taken in future clinical applications of plasmas. 15. Analysis of High Frequency Site-Specific Nitrogen and Oxygen Isotopic Composition of Atmospheric Nitrous Oxide at Mace Head, Ireland Science.gov (United States) McClellan, M. J.; Harris, E. J.; Olszewski, W.; Ono, S.; Prinn, R. G. 2014-12-01 Atmospheric nitrous oxide (N2O) significantly impacts Earth's climate due to its dual role as an inert potent greenhouse gas in the troposphere and as a reactive source of ozone-destroying nitrogen oxides in the stratosphere. However, there remain significant uncertainties in the global budget of this gas. The marked spatial divide in its reactivity means that all stages in the N2O life cycle—emission, transport, and destruction—must be examined to understand the overall effect of N2O on climate. Source and sink processes of N2O lead to varying concentrations of N2O isotopologues (14N14N16O, 14N15N16O, 15N14N16O, and 14N14N18O being measured) due to preferential isotopic production and elimination in different environments. Estimation of source and sink fluxes can be improved by combining isotopically resolved N2O observations with simulations using a chemical transport model with reanalysis meteorology and treatments of isotopic signatures of specific surface sources and stratospheric intrusions. We present the first few months of site-specific nitrogen and oxygen isotopic composition data from the Stheno-TILDAS instrument (Harris et al, 2013) at Mace Head, Ireland and compare these to results from MOZART-4 (Model for Ozone and Related Chemical Tracers, version 4) chemical transport model runs including N2O isotopic fractionation processes and reanalysis meterological fields (NCEP/NCAR, MERRA, and GEOS-5). This study forms the basis for future inverse modeling experiments that will improve the accuracy of isotopically differentiated N2O emission and loss estimates. Ref: Harris, E., D. Nelson, W. Olszewski, M. Zahniser, K. Potter, B. McManus, A. Whitehill, R. Prinn, and S. Ono, Development of a spectroscopic technique for continuous online monitoring of oxygen and site-specific nitrogen isotopic composition of atmospheric nitrous oxide, Analytical Chemistry, 2013; DOI: 10.1021/ac403606u. 16. Non-thermal atmospheric pressure HF plasma source: generation of nitric oxide and ozone for bio-medical applications Energy Technology Data Exchange (ETDEWEB) Kuehn, S; Gesche, R [Ferdinand-Braun-Institut (FBH), Gustav-Kirchhoff-Str. 4, 12489 Berlin (Germany); Bibinov, N; Awakowicz, P [Institute for Electrical Engineering and Plasma Technology, Ruhr-Universitaet Bochum, Universitaetsstr. 150, 44801 Bochum (Germany)], E-mail: Silvio.Kuehn@fbh-berlin.de, E-mail: Nikita.Bibinov@rub.de 2010-01-15 A new miniature high-frequency (HF) plasma source intended for bio-medical applications is studied using nitrogen/oxygen mixture at atmospheric pressure. This plasma source can be used as an element of a plasma source array for applications in dermatology and surgery. Nitric oxide and ozone which are produced in this plasma source are well-known agents for proliferation of the cells, inhalation therapy for newborn infants, disinfection of wounds and blood ozonation. Using optical emission spectroscopy, microphotography and numerical simulation, the gas temperature in the active plasma region and plasma parameters (electron density and electron distribution function) are determined for varied nitrogen/oxygen flows. The influence of the gas flows on the plasma conditions is studied. Ozone and nitric oxide concentrations in the effluent of the plasma source are measured using absorption spectroscopy and electro-chemical NO-detector at variable gas flows. Correlations between plasma parameters and concentrations of the particles in the effluent of the plasma source are discussed. By varying the gas flows, the HF plasma source can be optimized for nitric oxide or ozone production. Maximum concentrations of 2750 ppm and 400 ppm of NO and O{sub 3}, correspondingly, are generated. 17. Non-thermal atmospheric pressure HF plasma source: generation of nitric oxide and ozone for bio-medical applications International Nuclear Information System (INIS) A new miniature high-frequency (HF) plasma source intended for bio-medical applications is studied using nitrogen/oxygen mixture at atmospheric pressure. This plasma source can be used as an element of a plasma source array for applications in dermatology and surgery. Nitric oxide and ozone which are produced in this plasma source are well-known agents for proliferation of the cells, inhalation therapy for newborn infants, disinfection of wounds and blood ozonation. Using optical emission spectroscopy, microphotography and numerical simulation, the gas temperature in the active plasma region and plasma parameters (electron density and electron distribution function) are determined for varied nitrogen/oxygen flows. The influence of the gas flows on the plasma conditions is studied. Ozone and nitric oxide concentrations in the effluent of the plasma source are measured using absorption spectroscopy and electro-chemical NO-detector at variable gas flows. Correlations between plasma parameters and concentrations of the particles in the effluent of the plasma source are discussed. By varying the gas flows, the HF plasma source can be optimized for nitric oxide or ozone production. Maximum concentrations of 2750 ppm and 400 ppm of NO and O3, correspondingly, are generated. 18. Nitrous oxide in the Schelde estuary: production by nitrification and emission to the atmosphere NARCIS (Netherlands) De Wilde, H.; De Bie, M.J.M. 2000-01-01 Concentrations of nitrous oxide (N2O), oxygen, nitrate, and ammonium, as well as nitrification activity were determined along the salinity gradient of the Schelde Estuary, Northwest Europe, in October 1993, March 1994, and July 1996, The entire estuary was always supersaturated with N2O. Concentrati 19. Oxidative stress on plasmid DNA induced by inhalable particles in the urban atmosphere Institute of Scientific and Technical Information of China (English) SHI Zongbo; SHAO Longyi; T. P. Jones; A. G. Whittaker; R. J. Richards; ZHANG Pengfei 2004-01-01 Plasmid DNA assay is a newly-developed in vitro method to investigate bioreactivity of particles. In this paper, this method was used to study the bioreactivity of PM10 (particulate matter with aerodynamic diameter of less than 10цm) and PM2.5 (particulate matter with aerodynamic diameter of less than 2.5 цm). Samples and dust storm particles were collected in 2001 in an urban area, a satellite city and a clean air area in Beijing. A big difference was found for oxidative DNA stress induced by different particulate matter (PM) samples, with the TM50 (particle mass causing 50% damage to DNA) values varying by a factor over 10. This was closely dependent on the sizes of particles as well as the variation in relative proportion of mineral matter. PM2.5 samples generally impose larger oxidative stress on plasmid DNA than PM10 samples. Airborne particles collected during dust storm episodes, usually with a higher proportion of mineral matter, have a much lower oxidative capacity than those collected during non-dust storm episodes. PM samples and their water-soluble fractions usually have similar bioreactivities, demonstrating that oxidative capacity of Beijing airborne particles is mainly sourced from their water-soluble fractions. 20. Different Atmospheric Methane-Oxidizing Communities in European Beech and Norway Spruce Soils▿ † OpenAIRE Degelmann, Daniela M.; Borken, Werner; Drake, Harold L; Kolb, Steffen 2010-01-01 Norway spruce (Picea abies) forests exhibit lower annual atmospheric methane consumption rates than do European beech (Fagus sylvatica) forests. In the current study, pmoA (encoding a subunit of membrane-bound CH4 monooxygenase) genes from three temperate forest ecosystems with both beech and spruce stands were analyzed to assess the potential effect of tree species on methanotrophic communities. A pmoA sequence difference of 7% at the derived protein level correlated with the species-level d... 1. Preparation of Aluminium Oxynitride by Carbothermal Reduction of Aluminium Oxide in a Flowing N2 Atmosphere Institute of Scientific and Technical Information of China (English) LIYa－wei; YUANRun－zhang; 等 1996-01-01 Carbothermal reduction of alumina into aluminium oxynitride(AlON) spinel in a flowing nitrogen atmosphere was studied.The effects of Al2O3/C ratio temperature,soaking time,heating rate molding pressure of samples,and nitrogen flow rate on reactions were investigated.Then the stability of AlON was elucidated and AlON wa confirmed as an intermediate compound in reduction of alumina. 2. Effect of surface oxide film and atmosphere on microwave heating of compacted copper powder International Nuclear Information System (INIS) The microwave irradiation was performed using a compacted Cu powder under different oxygen partial pressures. After reaching about 600 K, an abrupt temperature rise and drop occurred. The abrupt temperature drop is caused by both sintering of Cu powder particles and growing of surface oxide film. The magnitude of the abrupt temperature drop decreased with increasing oxygen partial pressure. The temperature then remained constant (steady state), gradually increased or exhibited a secondary significant increase. The magnitude of the temperature rise after abrupt temperature drop increased with increasing oxygen partial pressure. The microwave heating behavior of the compacted Cu powder depended on the type and thickness of the surface oxide film and also on the type and volume fraction of the gas occupying the vacant spaces between the Cu powder particles. 3. Influence of Inert and Oxidizing Atmospheres on the Physical and Optical Properties of Luminescent Carbon Dots Prepared through Pyrolysis of a Model Molecule. Science.gov (United States) Machado, Cláudia Emanuele; Tartuci, Letícia Gazola; de Fátima Gorgulho, Honória; de Oliveira, Luiz Fernando Cappa; Bettini, Jefferson; Pereira dos Santos, Daniela; Ferrari, Jefferson Luis; Schiavon, Marco Antônio 2016-03-18 This work used L-tartaric acid as a model molecule to evaluate how the use of inert and oxidizing atmospheres during pyrolysis affected the physical and optical properties of the resulting carbon dots (CDs). Pyrolysis revealed to be a simple procedure that afforded CDs in a single step, dismissed the addition of organic solvents, and involved only one extraction stage that employed water. By X-ray diffraction a dependency between the structure of the CDs and the atmosphere (oxidizing or inert) used during the pyrolysis was found. Potentiometric titration demonstrated that the CDs were largely soluble in water; it also aided characterization of the various groups that contained sp(3) -hybridized carbon atoms on the surface of the dots. Raman spectroscopy suggested that different amounts of sp(2)- and sp(3)-hybridized carbon atoms emerged on the CDs depending on the pyrolysis atmosphere. In conclusion, the pyrolysis atmosphere influenced the physical properties, such as the composition and the final structure. 4. Mercury oxidation via chlorine, bromine, and iodine under atmospheric conditions: thermochemistry and kinetics. Science.gov (United States) Auzmendi-Murua, Itsaso; Castillo, Álvaro; Bozzelli, Joseph W 2014-04-24 Emissions of gaseous mercury from combustion sources are the major source of Hg in the atmosphere and in environmental waters and soils. Reactions of Hg(o)(g) with halogens are of interest because they relate to mercury and ozone depletion events in the Antarctic and Arctic early spring ozone hole events, and the formation of Hg-halides (HgX2) is a method for removal of mercury from power generation systems. Thermochemistry and kinetics from published theoretical and experimental studies in the literature and from computational chemistry are utilized to compile a mechanism of the reactions considered as contributors to the formation of HgX2 (X = Cl, Br, I) to understand the reaction paths and mechanisms under atmospheric conditions. Elementary reaction mechanisms are assembled and evaluated using thermochemistry for all species and microscopic reversibility for all reactions. Temperature and pressure dependence is determined with quantum Rice Ramsperger Kassel (RRK) analysis for k(E) and master equation analysis for fall-off. We find that reactions of mercury with a small fraction of the reactor surface or initiation by low concentrations of halogen atoms is needed to explain the experimental conversion of Hg to HgX2 in the gas phase. The models do not replicate data from experiments that do not explicitly provide an atom source. The Hg insertion reaction into X2 (Hg + X2 → HgX2) that has been reported is further studied, and we find agreement with studies that report high barriers. The high barriers prevent this insertion path from explaining the experimental data on HgX2 formation and Hg conversion under atmospheric conditions. Mechanism studies with low initial concentrations of halogen radicals show significant conversion of Hg under the experimental conditions. PMID:24661061 5. Microkinetics of H2S Removal by Zinc Oxide in the Presence of Moist Gas Atmosphere Institute of Scientific and Technical Information of China (English) Huiling Fan; Chunhu Li; Hanxian Guo; Kechang Xie 2003-01-01 The microkinetics of H2S removal by ZnO desulfurization in H2O-CO2-N2, H2O-CO-N2 andH2O-O2-N2 gas mixtures was studied by thermogravimetric analysis. Experiments were carried out with100 120 mesh ZnO powder at temperatures from 473 K to 563 K. The results show that the kineticbehaviors of desulfurization could all be described by an improved shrinking-core model. The activationenergies of the reaction and the diffusion in different gas atmospheres were estimated. 6. Atmospheric oxidation of sulphur dioxide in water droplets in presence of ammonia Energy Technology Data Exchange (ETDEWEB) McKay, H.A.C. 1971-01-01 The kinetics of the conversion of ammonia and sulphur dioxide to ammonium sulphate in water droplets in the atmosphere in the absence of metal ion catalysts has been reconsidered. It is concluded that the reaction is an order of magnitude faster than earlier work suggested, and that lowering the temperature increases the rate by a large factor. In a cloud or a thick mist appreciable amounts of ammonium sulphate may be formed in a few minutes; nevertheless a substantial proportion of unreacted ammonia may sometimes persist for hours, even though excess sulphur dioxide is present and the initial reaction is fast. 7. Theoretical perspectives on the mechanism and kinetics of the OH radical-initiated gas-phase oxidation of PCB126 in the atmosphere Energy Technology Data Exchange (ETDEWEB) Dang, Juan; Shi, Xiangli; Zhang, Qingzhu, E-mail: zqz@sdu.edu.cn; Wang, Wenxing 2015-06-01 Energy Technology Data Exchange (ETDEWEB) Rodney Andrews; Aurora Rubel; Jack Groppo; Brock Marrs; Ari Geertsema; Frank Huggins; M. Mercedes Maroto-Valer; Brandie M. Markley; Zhe Lu; Harold Schobert 2006-08-31 With the passing of legislation designed to permanently cap and reduce mercury emissions from coal-fired utilities, it is more important than ever to develop and improve upon methods of controlling mercury emissions. One promising technique is carbon sorbent injection into the flue gas of the coal-fired power plant. Currently, this technology is very expensive as costly commercially activated carbons are used as sorbents. There is also a significant lack of understanding of the interaction between mercury vapor and the carbon sorbent, which adds to the difficulty of predicting the amount of sorbent needed for specific plant configurations. Due to its inherent porosity and adsorption properties as well as on-site availability, carbons derived from gasifiers are potential mercury sorbent candidates. Furthermore, because of the increasing restricted use of landfilling, the coal industry is very interested in finding uses for these materials as an alternative to the current disposal practice. The results of laboratory investigations and supporting technical assessments conducted under DOE Subcontract No. DE-FG26-03NT41795 are reported. This contract was with the University of Kentucky Research Foundation, which supports work with the University of Kentucky Center for Applied Energy Research and The Pennsylvania State University Energy Institute. The worked described was part of a project entitled ''Advanced Gasification By-Product Utilization''. This work involved the development of technologies for the separation and characterization of coal gasification slags from operating gasification units, activation of these materials to increase mercury and nitrogen oxide capture efficiency, assessment of these materials as sorbents for mercury and nitrogen oxides, assessment of the potential for leaching of Hg captured by the carbons, analysis of the slags for cement applications, and characterization of these materials for use as polymer fillers. The 9. Surface reactivity and oxygen migration in amorphous indium-gallium-zinc oxide films annealed in humid atmosphere International Nuclear Information System (INIS) An isotope tracer study, i.e., 18O/16O exchange using 18O2 and H218O, was performed to determine how post-deposition annealing (PDA) affected surface reactivity and oxygen diffusivity of amorphous indium–gallium–zinc oxide (a-IGZO) films. The oxygen tracer diffusivity was very high in the bulk even at low temperatures, e.g., 200 °C, regardless of PDA and exchange conditions. In contrast, the isotope exchange rate, dominated by surface reactivity, was much lower for 18O2 than for H218O. PDA in a humid atmosphere at 400 °C further suppressed the reactivity of O2 at the a-IGZO film surface, which is attributable to –OH-terminated surface formation 10. Oxidation of siloxanes during biogas combustion and nanotoxicity of Si-based particles released to the atmosphere. Science.gov (United States) Tansel, Berrin; Surita, Sharon C 2014-01-01 Siloxanes have been detected in the biogas produced at municipal solid waste landfills and wastewater treatment plants. When oxidized, siloxanes are converted to silicon oxides. The objectives of this study were to evaluate the transformation of siloxanes and potential nanotoxicity of Si-based particles released to the atmosphere from the gas engines which utilize biogas. Data available from nanotoxicity studies were used to assess the potential health risks associated with the inhalation exposure to Si-based nanoparticles. Silicon dioxide formed from siloxanes can range from 5 nm to about 100 nm in diameter depending on the combustion temperature and particle clustering characteristics. In general, silicon dioxide particles formed during from combustion process are typically 40-70 nm in diameter and can be described as fibrous dusts and as carcinogenic, mutagenic, astmagenic or reproductive toxic (CMAR) nanoparticles. Nanoparticles deposit in the upper respiratory system, conducting airways, and the alveoli. Size ranges between 5 and 50 nm show effective deposition in the alveoli where toxic effects are higher. In this study the quantities for the SiO₂ formed and release during combustion of biogas were estimated based on biogas utilization characteristics (gas compositions, temperature). The exposure to Si-based particles and potential effects in humans were analyzed in relation to their particle size, release rates and availability in the atmosphere. The analyses showed that about 54.5 and 73 kg/yr of SiO₂ can be released during combustion of biogas containing D4 and D5 at 14.1 mg/m(3) (1 ppm) and 15.1 mg/m(3) (1ppm), respectively, per MW energy yield. 11. Laboratory Studies of Processing of Carbonaceous Aerosols by Atmospheric Oxidants/Hygroscopicity and CCN Activity of Secondary & Processed Primary Organic Aerosols Energy Technology Data Exchange (ETDEWEB) Ziemann, P.J.; Arey, J.; Atkinson, R.; Kreidenweis, S.M.; Petters, M.D. 2012-06-13 The atmosphere is composed of a complex mixture of gases and suspended microscopic aerosol particles. The ability of these particles to take up water (hygroscopicity) and to act as nuclei for cloud droplet formation significantly impacts aerosol light scattering and absorption, and cloud formation, thereby influencing air quality, visibility, and climate in important ways. A substantial, yet poorly characterized component of the atmospheric aerosol is organic matter. Its major sources are direct emissions from combustion processes, which are referred to as primary organic aerosol (POA), or in situ processes in which volatile organic compounds (VOCs) are oxidized in the atmosphere to low volatility reaction products that subsequent condense to form particles that are referred to as secondary organic aerosol (SOA). POA and VOCs are emitted to the atmosphere from both anthropogenic and natural (biogenic) sources. The overall goal of this experimental research project was to conduct laboratory studies under simulated atmospheric conditions to investigate the effects of the chemical composition of organic aerosol particles on their hygroscopicity and cloud condensation nucleation (CCN) activity, in order to develop quantitative relationships that could be used to more accurately incorporate aerosol-cloud interactions into regional and global atmospheric models. More specifically, the project aimed to determine the products, mechanisms, and rates of chemical reactions involved in the processing of organic aerosol particles by atmospheric oxidants and to investigate the relationships between the chemical composition of organic particles (as represented by molecule sizes and the specific functional groups that are present) and the hygroscopicity and CCN activity of oxidized POA and SOA formed from the oxidation of the major classes of anthropogenic and biogenic VOCs that are emitted to the atmosphere, as well as model hydrocarbons. The general approach for this project was 12. Plant species diversity affects soil-atmosphere fluxes of methane and nitrous oxide. Science.gov (United States) Niklaus, Pascal A; Le Roux, Xavier; Poly, Franck; Buchmann, Nina; Scherer-Lorenzen, Michael; Weigelt, Alexandra; Barnard, Romain L 2016-07-01 Plant diversity effects on ecosystem functioning can potentially interact with global climate by altering fluxes of the radiatively active trace gases nitrous oxide (N2O) and methane (CH4). We studied the effects of grassland species richness (1-16) in combination with application of fertilizer (nitrogen:phosphorus:potassium = 100:43.6:83 kg ha(-1) a(-1)) on N2O and CH4 fluxes in a long-term field experiment. Soil N2O emissions, measured over 2 years using static chambers, decreased with species richness unless fertilizer was added. N2O emissions increased with fertilization and the fraction of legumes in plant communities. Soil CH4 uptake, a process driven by methanotrophic bacteria, decreased with plant species numbers, irrespective of fertilization. Using structural equation models, we related trace gas fluxes to soil moisture, soil inorganic N concentrations, nitrifying and denitrifying enzyme activity, and the abundance of ammonia oxidizers, nitrite oxidizers, and denitrifiers (quantified by real-time PCR of gene fragments amplified from microbial DNA in soil). These analyses indicated that plant species richness increased soil moisture, which in turn increased N cycling-related activities. Enhanced N cycling increased N2O emission and soil CH4 uptake, with the latter possibly caused by removal of inhibitory ammonium by nitrification. The moisture-related indirect effects were surpassed by direct, moisture-independent effects opposite in direction. Microbial gene abundances responded positively to fertilizer but not to plant species richness. The response patterns we found were statistically robust and highlight the potential of plant biodiversity to interact with climatic change through mechanisms unrelated to carbon storage and associated carbon dioxide removal. PMID:27038993 13. Determination of nitrogen in uranium-plutonium mixed oxide fuel by gas chromatography after fusion in an inert gas atmosphere International Nuclear Information System (INIS) A gas chromatographic technique has been developed for the determination of nitrogen in uranium-plutonium mixed oxide fuel after fusion in an inert gas atmosphere. When the sample and pure iron powder in a graphite crucible were heated to approximately 2500C by a resistance heating furnace, a large amount of carbon monoxide was evolved with a small amount of nitrogen and hydrogen. A gas chromatograph equipped with a pre-cut system was used for the separation of nitrogen from the carbon monoxide. Nitrogen separated by the gas chromatograph was determined by means of a thermal conductivity detector. Only 100mg of the sample was used, and the analysis requires about 10min. No specific skills for glove-box work are necessary. The relative standard deviation and detection limit (3σ-criterion) were less than 5% and 9μgg-1, respectively. The present method is not only applicable to the analysis of research samples but also to the quality control of uranium-plutonium mixed oxide fuel production lines 14. Electrochromic properties of novel atmospheric pressure plasma jet-synthesized-organotungsten oxide films for flexible electrochromic devices Energy Technology Data Exchange (ETDEWEB) Lin, Y.-S.; Wu, S.-S.; Tsai, T.-H. [Department of Chemical Engineering, Feng Chia University, No.100, Wenhwa Road, Seatwen, Taichung, Taiwan 407 (China) 2010-12-15 An investigation was conducted in electrochromic performance of organotungsten oxide WO{sub x}C{sub y} films deposited onto 40 {omega}/square flexible PET (polyethylene terephthalate)/ITO (indium tin oxide) substrates using atmospheric pressure plasma jet (APPJ) at various precursor injection angles. A precursor [tungsten carbonyl, W(CO){sub 6};TC] vapor, carried by argon gas, was injected into air plasma torch. The APPJ-synthesized WO{sub x}C{sub y} films were proven to offer extraordinary electrochromic performance. Cyclic voltammetry (CV) switching measurements indicated that only low driving voltages from -1 to +1 V are needed to offer reversible Li{sup +} ion intercalation and de-intercalation in a 1 M LiClO{sub 4}-propylene carbonate (PC) electrolyte. Light modulation with up to 72.5% transmittance variation, optical density change of 0.84 and coloration efficiency of 49.6 cm{sup 2}/mC at a wavelength of 797.6 nm after 200 cycles of Li{sup +} ion intercalation and deintercalation were obtained. (author) 15. Impact of Atmospheric Microparticles on the Development of Oxidative Stress in Healthy City/Industrial Seaport Residents Directory of Open Access Journals (Sweden) Kirill Golokhvast 2015-01-01 Full Text Available Atmospheric microsized particles producing reactive oxygen species can pose a serious health risk for city residents. We studied the responses of organisms to microparticles in 255 healthy volunteers living in areas with different levels of microparticle air pollution. We analyzed the distribution of microparticles in snow samples by size and content. ELISA and flow cytometry methods were employed to determine the parameters of the thiol-disulfide metabolism, peroxidation and antioxidant, genotoxicity, and energy state of the leukocytes. We found that, in the park areas, microparticles with a size of 800 μm or more were predominant (96%, while in the industrial areas, they tended to be less than 50 μm (93%, including size 200–300 nm (7%. In the industrial areas, we determined the oxidative modification of proteins (21% compared to the park areas, p≤0.05 and DNA (12%, p≤0.05, as well as changes in leukocytes’ energy potential (53%, p≤0.05. An increase in total antioxidant activity (82%, p≤0.01 and thiol-disulfide system response (thioredoxin increasing by 33%, p≤0.01; glutathione, 30%, p≤0.01 with stable reductases levels maintains a balance of peroxidation-antioxidant processes, protecting cellular and subcellular structures from significant oxidative damage. 16. Gas chromatographic vapor pressure determination of atmospherically relevant oxidation products of β-caryophyllene and α-pinene Science.gov (United States) Hartonen, Kari; Parshintsev, Jevgeni; Vilja, Vesa-Pekka; Tiala, Heidi; Knuuti, Sinivuokko; Lai, Ching Kwan; Riekkola, Marja-Liisa 2013-12-01 Vapor pressures (subcooled liquid, pliquid) of atmospherically relevant oxidation products of β-caryophyllene (β-caryophyllene aldehyde 0.18 ± 0.03 Pa and β-nocaryophyllene aldehyde 0.17 ± 0.03 Pa), and α-pinene (pinonaldehyde 16.8 ± 0.20 Pa, cis-pinic acid 0.12 ± 0.06 Pa, and cis-pinonic acid 0.99 ± 0.19 Pa) at 298 K were obtained by gas chromatography with flame ionization detection (FID) and mass spectrometric (MS) detection. The effects of stationary phase polarity and column film thickness on the vapor pressure values were investigated. Increase in stationary phase polarity provided smaller values, while increase in film thickness gave slightly higher values. Values for vapor pressure were at least two orders of magnitude lower when obtained by a method utilizing vaporization enthalpy (determined by gas chromatography-mass spectrometry) than by retention index method. Finally, the results were compared with values calculated by group contribution theory. For the β-caryophyllene oxidation products, the values measured by gas chromatography were slightly lower than those obtained by theoretical calculations. The opposite trend was observed for the α-pinene oxidation products. The methods based on gas chromatography are concluded to be highly useful for the determination of vapor pressures of semi-volatile compounds. Except for the most polar pinic and pinonic acids, differences between vapor pressure values obtained by GC-FID and GC-MS were small. Since GC-MS provides structural information simultaneously, the use of GC-MS is recommended. 17. Synthesis and modeling of uniform complex metal oxides by close-proximity atmospheric pressure chemical vapor deposition. Science.gov (United States) Hoye, Robert L Z; Muñoz-Rojas, David; Musselman, Kevin P; Vaynzof, Yana; MacManus-Driscoll, Judith L 2015-05-27 A close-proximity atmospheric pressure chemical vapor deposition (AP-CVD) reactor is developed for synthesizing high quality multicomponent metal oxides for electronics. This combines the advantages of a mechanically controllable substrate-manifold spacing and vertical gas flows. As a result, our AP-CVD reactor can rapidly grow uniform crystalline films on a variety of substrate types at low temperatures without requiring plasma enhancements or low pressures. To demonstrate this, we take the zinc magnesium oxide (Zn(1-x)Mg(x)O) system as an example. By introducing the precursor gases vertically and uniformly to the substrate across the gas manifold, we show that films can be produced with only 3% variation in thickness over a 375 mm(2) deposition area. These thicknesses are significantly more uniform than for films from previous AP-CVD reactors. Our films are also compact, pinhole-free, and have a thickness that is linearly controllable by the number of oscillations of the substrate beneath the gas manifold. Using photoluminescence and X-ray diffraction measurements, we show that for Mg contents below 46 at. %, single phase Zn(1-x)Mg(x)O was produced. To further optimize the growth conditions, we developed a model relating the composition of a ternary oxide with the bubbling rates through the metal precursors. We fitted this model to the X-ray photoelectron spectroscopy measured compositions with an error of Δx = 0.0005. This model showed that the incorporation of Mg into ZnO can be maximized by using the maximum bubbling rate through the Mg precursor for each bubbling rate ratio. When applied to poly(3-hexylthiophene-2,5-diyl) hybrid solar cells, our films yielded an open-circuit voltage increase of over 100% by controlling the Mg content. Such films were deposited in short times (under 2 min over 4 cm(2)). PMID:25939729 18. Were ancient granitoid compositions influenced by contemporaneous atmospheric and hydrosphere oxidation states? Science.gov (United States) Jagoutz, O. E. 2013-12-01 A fundamental shift in the nature of granitoids occurs at approximately the Archean-Proterozoic boundary. Archean crust is dominated Na-rich tonalite-trondhjemite-granodiorites (TTGs), whereas post-Archean granitoids are characterized by K-rich granodiorite-granite (GG). Due to the HREE depletion commonly found in TTGs indicating the presence of residual garnet, many researchers have proposed that the difference in Na/K is related to the deeper melting depth of the TTG parental liquids. Here I present a compilation of the relevant experimental data, documenting that no correlation exists between the Na/K of derivative felsic liquids and the pressure of partial melting/fractional crystallization. Instead, the Na/K ratio of the felsic liquid best correlates with the Na/K ratio of the source. This implies that in Archean time the source material of TTG rocks must have been Na/K enriched relative to the modern. Modern granitoids are dominantly formed in a supra subduction zone environment, where a feedback loop exists between subducted materials (oceanic crust and sediments) and arc magmatism. Sea-floor weathering and the Na/K of the altered oceanic crust strongly depends on f(O2) conditions during alteration, which likely changed with earth history. During alteration under oxidized condition K2O is fixated due to the formation of celadonite (K-Mica), wheres during anoxic condition saponite (Na-Smectite) is the stable alteration mineral. I propose that the rise of oxygen at 2600-2400 Ma triggered associated changes in f(O2) seafloor alteration conditions. The change in the dominant seafloor alteration mineral from reduced to oxidized causes a change in the nature of the arc magma source and provides a possible explanation for the observed transition from TTGrocks in the Archean to the GG-granitoids in post-Archean times. Energy Technology Data Exchange (ETDEWEB) Rodney Andrews; Aurora Rubel; Jack Groppo; Ari Geertsema; M. Mercedes Maroto-Valer; Zhe Lu; Harold Schobert 2005-04-01 The results of laboratory investigations and supporting technical assessments conducted under DOE Subcontract No. DE-FG26-03NT41795 are reported for the period September 1, 2003 to August 31, 2004. This contract is with the University of Kentucky Research Foundation, which supports work with the University of Kentucky Center for Applied Energy Research and The Pennsylvania State University Energy Institute. The worked described was part of a project entitled ''Advanced Gasification By-Product Utilization''. This work involves the development of technologies for the separation and characterization of coal gasification slags from operating gasification units, activation of these materials to increase mercury and nitrogen oxide capture efficiency, assessment of these materials as sorbents for mercury and nitrogen oxides, and characterization of these materials for use as polymer fillers. 20. Soil-Atmosphere Exchange of Nitrous Oxide, Nitric Oxide, Methane, and Carbon Dioxide in Logged and Undisturbed Forest in the Tapajos National Forest, Brazil Science.gov (United States) Keller, M.; Varner, R. K.; Dias, J. D.; Silva, H.; Crill, P. M.; de Oliveira, R. C.; Asner, G. P. 2004-12-01 Selective logging is an extensive land use in the Brazilian Amazon region. We studied the soil-atmosphere fluxes of nitrous oxide (N2O), nitric oxide (NO), methane (CH4), and carbon dioxide (CO2) on two soil types (clay Oxisol and sandy loam Ultisol) over two years (2000-2001) in both undisturbed forest and forest recently logged using reduced impact forest management in the Tapajos National Forest, near Santarem, Para, Brazil. In undisturbed forest, annual soil-atmosphere fluxes of N2O (mean +/- standard error) were 7.9 +/- 0.7 and 7.0 +/- 0.6 ng N cm-2 h-1 for the Oxisol and 1.7 +/- 0.1 and 1.6 +/- 0.3 ng N cm-2 h-1 for the Ultisol for 2000 and 2001 respectively. The annual fluxes of NO from undisturbed forest soil in 2001 was 9.0 +/- 2.8 ng N cm-2 h-1 for the Oxisol and 8.8 +/- 5.0 ng N cm-2 h-1 for the Ultisol. Consumption of CH4 from the atmosphere dominated over production on undisturbed forest soils. Fluxes averaged -0.3 +/- 0.2 and -0.1 +/- 0.9 mg CH4 m-2 d-1 on the Oxisol and -1.0 +/- 0.2 and -0.9 +/- 0.3 mg CH4 m-2 d-1 on the Ultisol for years 2000 and 2001. For CO2 in 2001, the annual fluxes averaged 3.6 +/- 0.4 μ mol m-2 d-1 on the Oxisol and 4.9 +/- 1.1 μ mol m-2 d-1 on the Ultisol. We measured fluxes over one year each from two recently logged forests on the Oxisol in 2000 and on the Ultisol in 2001. Sampling in logged areas was stratified from greatest to least ground disturbance covering log decks, skid trails, tree-fall gaps, and forest matrix. Areas of strong soil compaction, especially the skid trails and logging decks were prone to significantly greater emissions of N2O, NO, and especially CH4. In the case of CH4, estimated annual emissions from decks reached extremely high rates of 531 +/- 419 and 98 +/- 41 mg CH4 m-2 d-1, for Oxisol and Ultisol respectively, comparable to wetland emissions in the region. We calculated excess fluxes from logged areas by subtraction of a background forest flux and adjusted these fluxes for the proportional 1. The influence of atmospheric species on the degradation of aluminum doped zinc oxide and Cu(In,Ga)Se2 solar cells NARCIS (Netherlands) Theelen, M.J.; Foster, C.; Dasgupta, S.; Vroon, Z.A.E.P.; Barreau, N.; Zeman, M. 2014-01-01 Aluminum doped zinc oxide (ZnO:Al) layers were exposed to the atmospheric gases carbondioxide (CO2), oxygen (O2), nitrogen (N2) and air as well as liquid H2O purged with these gases, in order to investigate the chemical degradation behavior of these layers. The samples were analyzed by electrical, c 2. Atmospheric methane removal by methane-oxidizing bacteria immobilized on porous building materials. Science.gov (United States) Ganendra, Giovanni; De Muynck, Willem; Ho, Adrian; Hoefman, Sven; De Vos, Paul; Boeckx, Pascal; Boon, Nico 2014-04-01 Biological treatment using methane-oxidizing bacteria (MOB) immobilized on six porous carrier materials have been used to mitigate methane emission. Experiments were performed with different MOB inoculated in building materials at high (~20 % (v/v)) and low (~100 ppmv) methane mixing ratios. Methylocystis parvus in autoclaved aerated concrete (AAC) exhibited the highest methane removal rate at high (28.5 ± 3.8 μg CH₄ g⁻¹ building material h⁻¹) and low (1.7 ± 0.4 μg CH₄ g⁻¹ building material h⁻¹) methane mixing ratio. Due to the higher volume of pores with diameter >5 μm compared to other materials tested, AAC was able to adsorb more bacteria which might explain for the higher methane removal observed. The total methane and carbon dioxide-carbon in the headspace was decreased for 65.2 ± 10.9 % when M. parvus in Ytong was incubated for 100 h. This study showed that immobilized MOB on building materials could be used to remove methane from the air and also act as carbon sink. PMID:24337222 3. A flow reactor study of neopentane oxidation at 8 atmospheres: Experiments and modeling Energy Technology Data Exchange (ETDEWEB) Wang, S.; Miller, D.L.; Cernansky, N.P. [Drexel Univ., Philadelphia, PA (United States). Dept. of Mechanical Engineering and Mechanics; Curran, H.J.; Pitz, W.J.; Westbrook, C.K. [Lawrence Livermore National Lab., CA (United States) 1999-08-01 An existing detailed chemical kinetic reaction mechanism for neopentane oxidation is applied to new experimental measurements, taken in a flow reactor operating at a pressure of 8 atm. The reactor temperature ranged from 620 K to 810 K and flow rates of the reactant gases neopentane, oxygen, and nitrogen were 0.285, 7.6, and 137.1 standard liter per minute (SLM), respectively, producing an equivalence ratio of 0.3. Initial simulations identified some deficiencies in the existing model and the paper presents modifications which included upgrading the thermodynamic parameters of alkyl radical and alkylperoxy radical species, adding an alternative isomerization reaction of hydroperoxy-neopentyl-peroxy, and a multistep reaction sequence for 2-methylpropan-2-yl radical with molecular oxygen. These changes improved the calculation for the overall reactivity and the concentration profiles of the following primary products: formaldehyde, acetone, isobutene; 3,3-dimethyloxetane, methacrolein, carbon monoxide, carbon dioxide, and water. Experiments indicate that neopentane shows negative temperature coefficient behavior similar to other alkanes, though it is not as pronounced as that shown by n-pentane for example. Modeling results indicate that this behavior is caused by the {beta}-scission of the neopentyl radical and the chain propagation reactions of the hydroperoxyl-neopentyl radical. 4. Influence of packaging atmosphere on the formation of cholesterol oxides in [gamma]-irradiated egg powder Energy Technology Data Exchange (ETDEWEB) Lebovics, V.K.; Gaal, O. (National Inst. of Food Hygiene and Nutrition, Budapest (Hungary)); Farkas, J.; Somogyi, L. (University of Horticulture and Food Industry, Budapest (Hungary)) 1993-09-01 In the present work the influence of aerobic and anoxic conditions have been comparatively investigated to study the chemical changes of cholesterol in [gamma]-irradiated egg powder. The irradiation treatment was carried out with powdered egg packed under air and also under vacuum in polyethylene (PE) bags and in laminated, oxygen impermeable three-layer (polyester-aluminium-polyethylene) foil to dosage levels 2 and 4 kGy at room temperature. The cholesterol oxidation is demonstrated by thin-layer chromatograms. In the egg powder wrapped in Pe bags the predominant cholesterol derivatives -7-hydroxycholesterol isomers ([alpha] and [beta]) - accumulated in significant amounts (increasing with dose) while vacuum-packaging in laminated foil considerably suppressed the quantity of these products and prevented the formation of cholesterol 5[alpha], 6[alpha]-epoxide as well as 7-ketocholesterol. Little or no change was observed in non-irradiated (control) vacuum-packed egg powder stored at approximately 22[sup o]C for up to 5 months. Peroxide values showed changes parallel to the formation of COPs. (author). 5. Modelling of gaseous dimethylamine in the global atmosphere: impacts of oxidation and aerosol uptake Directory of Open Access Journals (Sweden) F. Yu 2014-07-01 Full Text Available Recent laboratory studies indicate that while a dimethylamine concentration ([DMA] of several pptv can substantially enhance nucleation rates, such an enhancement drops significantly as [DMA] decreases below a few pptv. Here we study global distributions of amines with a chemistry transport model. DMA's lifetime is quite short (1–2 h in some regions due to aerosol uptake and oxidation. Aerosol uptake is important over regions of high anthropogenic emissions, while the decrease of the uptake coefficient (γ from 0.03 to 0.001 in these regions increases the modeled amine concentrations by a factor of ~5. Further decrease of γ from 0.001 to 0 has a small (<10% effect on the predicted amine concentrations. With the estimated global emission flux, from the reference, our simulations indicate that [DMA] in the surface layer is generally less than 1 pptv over major continents and below 0.1 pptv over oceans, decreasing quickly with altitude. Total concentrations of methylamines are about one order of magnitude higher than that of DMA. A comparison of simulated and observed [DMA] shows that the values of the simulated [DMA] are close to the measured values for the various urban sites but are substantially lower (by 1–2 orders of magnitude than those measured at the rural, coastal, and marine sites. 6. Self-sealing of unsealed aluminium anodic oxide films in very different atmospheres Directory of Open Access Journals (Sweden) González, J. A. 2003-12-01 Full Text Available It is widely believed that the corrosion resistance behaviour of bare aluminium in natural environments is superior to that of unsealed anodised aluminium. However, results obtained in the exposure of unsealed anodised aluminium specimens with three different film thicknesses, in 9 atmospheres of Ibero-America with salinity levels between 3.9 and 517 mg.m-2.d-1 chloride, clearly shows the reverse to be true. After a sufficient time, which is shorter the higher the precipitation rate and the environmental relative humidity, a self-sealing process takes place, leading to coatings that surpass the quality standards demanded in industrial practice. Anodic films, sealed and unsealed, are protective coatings whose quality improves with ageing in most natural environments. Está muy difundida la idea de que el comportamiento del aluminio es superior al del aluminio anodizado y sin sellar, desde el punto de vista de la resistencia a la corrosión, en los ambientes naturales. Sin embargo, los resultados obtenidos en la exposición de anodizados sin sellar, de tres espesores diferentes, a 9 atmósferas de Iberoamérica, con salinidades comprendidas entre 3,9 y 517 mg.m-2.d-1 de cloruros, muestran, sin lugar a dudas, lo contrario. Con tiempo suficiente, tanto más rápidamente cuanto mayor sean las precipitaciones y la humedad relativa ambiental, tiene lugar un proceso de autosellado que conduce a recubrimientos que superan las normas de calidad exigidas en la práctica industrial. Los anodizados, sellados y sin sellar, son recubrimientos protectores que mejoran su calidad, en la mayoría de los ambientes naturales, con el envejecimiento. 7. Mechanism and kinetics study on the OH-initiated oxidation of organophosphorus pesticide trichlorfon in atmosphere Energy Technology Data Exchange (ETDEWEB) Bao, Yuan; Zhang, Chenxi; Yang, Wenbo; Hu, Jingtian [Environment Research Institute, Shandong University, Jinan 250100 (China); Sun, Xiaomin, E-mail: sxmwch@sdu.edu.cn [Environment Research Institute, Shandong University, Jinan 250100 (China); State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy Of Science, Lanzhou 730000 (China) 2012-03-01 Trichlorfon [O,O-dimethyl-(2,2,2-trichloro-1-hydroxy-ethyl) phosphonate] (TCF) is a kind of widely used organophosphorus pesticides. In this paper, the mechanism and possible oxidation products for the OH-initiated reactions of TCF are studied at the MPWB1K/6-311 + G(3df,2p)//MPWB1K/6-31 + G(d,p) level. The study shows that H abstraction reaction from the CH{sub 3} group and the CH group as well as OH addition reaction to the P atom are energetically favorable for the reactions of TCF and the main products are (CH{sub 3}O){sub 2}POOH (P1), CCl{sub 3}CHOHPOOH(OCH{sub 3}) (P2), CH{sub 3}OPO{sub 2} (P3), CCl{sub 3}COPO(OCH{sub 3}){sub 2} (P6) and HCHO. On the basis of the quantum chemical information, the kinetic calculation is performed and the rate constants are calculated over a temperature range of 200-800 K using the transition state theory and canonical variational transition state theory with small-curvature tunneling effect. The Arrhenius formulas of rate constants with the temperature are fitted and the lifetimes of the reaction species in the troposphere are estimated according to the rate constants, which can provide helpful information for the model simulation study. - Highlights: Black-Right-Pointing-Pointer The H-abstracted reaction and OH addition reaction are favorable channels. Black-Right-Pointing-Pointer The Arrhenius formulas of rate constants with the temperature are fitted. Black-Right-Pointing-Pointer The rate constants of TCF relative to OH radical is 4.95 Multiplication-Sign 10{sup -15} cm{sup 3} molecule{sup -1} s{sup -1}. 8. Snowpack-atmosphere gas exchanges of carbon dioxide, ozone, and nitrogen oxides at a hardwood forest site in northern Michigan Directory of Open Access Journals (Sweden) Brian Seok 2015-03-01 Full Text Available Abstract Snowpack-atmosphere gas exchanges of CO2, O3, and NOx (NO + NO2 were investigated at the University of Michigan Biological Station (UMBS, a mid-latitude, low elevation hardwood forest site, during the 2007–2008 winter season. An automated trace gas sampling system was used to determine trace gas concentrations in the snowpack at multiple depths continuously throughout the snow-covered period from two adjacent plots. One natural plot and one with the soil covered by a Tedlar sheet were setup for investigating whether the primary source of measured trace gases was biogenic (i.e., from the soil or non-biogenic (i.e., from the snowpack. The results were compared with the “White on Green” study conducted at the Niwot Ridge (NWT Long Term Ecological Research site in Colorado. The average winter CO2 flux ± s.e. from the soil at UMBS was 0.54 ± 0.037 µmol m-2 s-1 using the gradient diffusion method and 0.71 ± 0.012 µmol m-2 s-1 using the eddy covariance method, and in a similar range as found for NWT. Observed snowpack-O3 exchange was also similar to NWT. However, nitrogen oxides (NOx fluxes from snow at UMBS were 10 times smaller than those at NWT, and fluxes were bi-directional with the direction of the flux dependent on NOx concentrations in ambient air. The compensation point for the change in the direction of NOx flux was estimated to be 0.92 nmol mol-1. NOx in snow also showed diurnal dependency on incident radiation. These NOx dynamics in the snow at UMBS were notably different compared to NWT, and primarily determined by snow-atmosphere interactions rather than by soil NOx emissions. 9. A Comparison of Process-Scale Modeling and Measurements of Atmosphere-Snowpack Exchange of Nitrogen Oxides at Summit, Greenland Science.gov (United States) Murray, K. A.; Helmig, D.; Kramer, L. J.; Doskey, P. V.; Van Dam, B. A.; Seok, B.; Ganzeveld, L. 2015-12-01 Snowpack over glacial ice is a reservoir for reactive nitrogen gases. Previous studies indicate nitrogen oxides (NOx) are generated in snowpack interstitial air through photolysis of nitrate (NO3-). Gradients in NOx mixing ratios between snowpack interstitial air and the overlying atmosphere regulate NOx surface exchange, which affects the Arctic ozone budget and climate. To better understand the dynamics of cryosphere-atmosphere exchange of NOx in the Arctic, we use a 1-D process-scale model to evaluate measurements of NOxin and above the snowpack during March-May 2009 at Summit, Greenland. The model is based upon the processes previously presented in the snowpack chemistry and physics model, MISTRA-SNOW, which represents snow grains as spheres with surfaces uniformly coated by an aqueous phase. Modeled profiles of NO, NO2, and O3 up to ~ 2 meters deep into the snowpack for March-May 2009 have been compared to measured profiles and will be presented. During the March-May time period at Summit, low irradiances are observed during March, diurnal irradiance profiles are observed during April, and the sun never sets in May. The model results suggest a key chemical pathway for the formation of NO2 during "nighttime" that was previously unexplained. In addition, modeled 24-hour NOx fluxes are compared to measured NOx fluxes from a MET tower at Summit. Modeled fluxes of NOx in April 2009 are the same order of magnitude as the measurements; however, modeled fluxes of NOx deviate up to one order of magnitude from measurements in May 2009. A detailed analysis of the modeled/measured flux comparison will be presented. 10. Oxidative capacity of the Mexico City atmosphere – Part 1: A radical source perspective Directory of Open Access Journals (Sweden) M. J. Molina 2007-04-01 11. Measurement and Modeling of Site-specific Nitrogen and Oxygen Isotopic Composition of Atmospheric Nitrous Oxide at Mace Head, Ireland Science.gov (United States) McClellan, M. J.; Saikawa, E.; Prinn, R. G.; Ono, S. 2015-12-01 Global mixing ratios of atmospheric nitrous oxide (N2O), a potent greenhouse gas, have increased nearly linearly from the beginning of the modern industrial period to today, with the current global average in excess of 325 ppb. This increase can be largely attributed to anthropogenic activity above the level of N2O emissions from natural biotic sources. The effect of N2O on Earth's climate is twofold: in the troposphere, N2O is radiatively active and chemically inert, while it serves as a reactive source of ozone-destroying nitrogen oxides in the stratosphere. The marked altitudinal divide in its reactivity means that all stages in the N2O life cycle—emission, transport, and destruction—must be examined to understand the overall effect of N2O on Earth's climate. However, the understanding of the total impact of N2O is incomplete, as there remain significant uncertainties in the global budget of this gas. Due to unique isotopic substitutions (15N and 18O) made by different N2O sources and stratospheric chemical reactions, the measurement of N2O isotopic ratios in ambient air can help identify the distribution and magnitude of distinct source types. We present the first year of site-specific nitrogen and oxygen isotopic composition data from the MIT Stheno-tunable infrared direct absorption spectroscopy (TILDAS) instrument at Mace Head, Ireland. Aided by the Stheno preconcentration system, Stheno-TILDAS can achieve measurement precisions of 0.10‰ or greater for all isotopic ratios (δ15N and δ18O) in ambient N2O. We further compare these data to the results from Model for Ozone and Related Tracers version 4 (MOZART-4) simulations, including N2O isotopic fractionation processes and MERRA/GEOS-5 reanalysis meteorological fields. These results will form the basis of future Bayesian inverse modeling simulations that will constrain global N2O source, circulation, and sink dynamics better. 12. Dissociation against oxidation kinetics for the conversion of VOCs in non-thermal plasmas of atmospheric gases Science.gov (United States) Pasquiers, Stéphane; Blin-Simiand, Nicole; Magne, Lionel 2016-08-01 The kinetics of four volatile organic compounds (VOCs) (propene, propane, acetaldehyde, acetone) were studied in plasmas of atmospheric gases using a photo-triggered discharge (homogeneous plasma) or a dielectric barrier discharge (filamentary plasma). It was shown for the homogeneous plasma that quenchings of nitrogen metastable states, A3Ʃ+u and the group of singlets a' 1Ʃ-u, a 1Πg and w 1∆u, are important processes for the decomposition of such molecules. Recent measurements of the H2 concentration produced in the N2/C3H6 mixture emphasize that the hydrogen molecule can be an exit route for propene dissociation. It is also found that H2 and CO molecules are efficiently produced following the dissociation of CH3COCH3 and the subsequent chemical reactivity induced by radicals coming from acetone. Addition of oxygen to a N2/VOC mixture can change drastically the kinetics. However, the quenching processes of N2 metastables by the VOC are always present and compete with oxidation reactions for the conversion of the pollutant. At low temperature, oxidations by O or by OH are not always sufficiently effective to induce an increase of the molecule decomposition when oxygen is added to the mixture. In particular, the presence of O2 has a detrimental effect on the acetone removal. Also, as evidenced for acetaldehyde and propane, some kinetic analogies appear between filamentary and homogeneous plasmas. Contribution to the topical issue "6th Central European Symposium on Plasma Chemistry (CESPC-6)", edited by Nicolas Gherardi, Ester Marotta and Cristina Paradisi 13. Non-OH chemistry in oxidation flow reactors for the study of atmospheric chemistry systematically examined by modeling Directory of Open Access Journals (Sweden) Z. Peng 2015-09-01 Full Text Available Oxidation flow reactors (OFRs using low-pressure Hg lamp emission at 185 and 254 nm produce OH radicals efficiently and are widely used in atmospheric chemistry and other fields. However, knowledge of detailed OFR chemistry is limited, allowing speculation in the literature about whether some non-OH reactants, including several not relevant for tropospheric chemistry, may play an important role in these OFRs. These non-OH reactants are UV radiation, O(1D, O(3P, and O3. In this study, we investigate the relative importance of other reactants to OH for the fate of reactant species in OFR under a wide range of conditions via box modeling. The relative importance of non-OH species is less sensitive to UV light intensity than to relative humidity (RH and external OH reactivity (OHRext, as both non-OH reactants and OH scale roughly proportional to UV intensity. We show that for field studies in forested regions and also the urban area of Los Angeles, reactants of atmospheric interest are predominantly consumed by OH. We find that O(1D, O(3P, and O3 have relative contributions to VOC consumption that are similar or lower than in the troposphere. The impact of O atoms can be neglected under most conditions in both OFR and troposphere. Under "pathological OFR conditions" of low RH and/or high OHRext, the importance of non-OH reactants is enhanced because OH is suppressed. Some biogenics can have substantial destructions by O3, and photolysis at non-tropospheric wavelengths (185 and 254 nm may also play a significant role in the degradation of some aromatics under pathological conditions. Working under low O2 with the OFR185 mode allows OH to completely dominate over O3 reactions even for the biogenic species most reactive with O3. Non-tropospheric VOC photolysis may have been a problem in some laboratory and source studies, but can be avoided or lessened in future studies by diluting source emissions and working at lower precursor concentrations in lab 14. Seasonal variability of atmospheric nitrogen oxides and non-methane hydrocarbons at the GEOSummit station, Greenland Directory of Open Access Journals (Sweden) L. J. Kramer 2014-05-01 Full Text Available Measurements of atmospheric NOx (NOx = NO + NO2, peroxyacetyl nitrate (PAN, NOy and non-methane hydrocarbons (NMHC were taken at the GEOSummit Station, Greenland (72.34° N, 38.29° W, 3212 m.a.s.l from July 2008 to July 2010. The data set represents the first year-round concurrent record of these compounds sampled at a high latitude Arctic site in the free troposphere. Here, the study focused on the seasonal variability of these important ozone (O3 precursors in the Arctic free troposphere and the impact from transported anthropogenic and biomass burning emissions. Our analysis shows that PAN is the dominant NOy species in all seasons at Summit, varying from 49% to 78%, however, we find that odd NOy species (odd NOy = NOy − PAN-NOx contribute a large amount to the total NOy speciation with monthly means of up to 95 pmol mol−1 in the winter and ∼40 pmol mol−1 in the summer, and that the level of odd NOy species at Summit during summer is greater than that of NOx. We hypothesize that the source of this odd NOy is most likely alkyl nitrates from transported pollution, and photochemically produced species such as HNO3 and HONO. FLEXPART retroplume analysis and tracers for anthropogenic and biomass burning emissions, were used to identify periods when the site was impacted by polluted air masses. Europe contributed the largest source of anthropogenic emissions during the winter and spring months, with up to 82% of the simulated anthropogenic black carbon originating from this region between December 2009 and March 2010, whereas, North America was the primary source of biomass burning emissions. Polluted air masses were typically aged, with median transport times to the site from the source region of 11 days for anthropogenic events in winter, and 14 days for BB plumes. Overall we find that the transport of polluted air masses to the high altitude Arctic typically resulted in high variability in levels of O3 and O3 precursors. During winter 15. Surface and optical properties of indium tin oxide layer deposition by RF magnetron sputtering in argon atmosphere Science.gov (United States) Yudar, H. Hakan; Korkmaz, Şadan; Özen, Soner; Şenay, Volkan; Pat, Suat 2016-08-01 This study focused on the characterization and properties of transparent and conductive indium tin oxide (ITO) thin films deposited in argon atmosphere. ITO thin films were coated onto glass substrates by radio frequency (RF) magnetron sputtering technique at 75 and 100 W RF powers. Structural characteristics of producing films were investigated through X-ray diffraction analysis. UV-Vis spectrophotometer and interferometer were used to determine transmittance, absorbance and reflectance values of samples. The surface morphology of the films was characterized by atomic force microscope. The calculated band gaps were 3.8 and 4.1 eV for the films at 75 and 100 W, respectively. The effect of RF power on crystallinity of prepared films was explored using mentioned analysis methods. The high RF power caused higher poly crystallinity in the produced samples. The thickness and refractive index values for all samples increased respect to an increment of RF power and were calculated as 20, 50 nm and 1.71, 1.86 for samples at 75 and 100 W, respectively. Finally, the estimated grain sizes for all prepared films decreased with increasing of 2 θ degrees, and the number of crystallite per unit volume was calculated. It was found that nearly all properties including sheet resistance and resistivity depend on the RF power. 16. Evaporation rates and vapor pressures of individual aerosol species formed in the atmospheric oxidation of alpha- and beta-pinene. Science.gov (United States) Bilde, M; Pandis, S N 2001-08-15 The semivolatile oxidation products (trans-norpinic acid, pinic acid, cis-pinonic acid, etc.) of the biogenic monoterpenes (alpha-pinene, beta-pinene, etc.) contribute to the atmospheric burden of particulate matter. Using the tandem differential mobility analysis (TDMA) technique evaporation rates of glutaric acid, trans-norpinic acid, and pinic acid particles were measured in a laminar flow reactor. The vapor pressure of glutaric acid was found to be log(p0 glutaric/Pa) = - 3,510 K/T + 8.647 over the temperature range 290-300 K in good agreement with the values previously reported by Tao and McMurry (1989). The measured vapor pressure of trans-norpinic acid over the temperature range 290-312 K is log(p0 norpinic/Pa) = - 2,196.9 K/T + 3.522, and the vapor pressure of pinic acid is log(p0 pinic/ Pa) = - 5,691.7 K/T + 14.73 over the temperature range 290-323 K. The uncertainty on the reported vapor pressures is estimated to be approximately +/- 50%. The vapor pressure of cis-pinonic acid is estimated to be of the order of 7 x 10(-5) Pa at 296 K. 17. Experimental and modeling study of the oxidation of acetaldehyde in an atmospheric-pressure pulsed corona discharge Science.gov (United States) Klett, C.; Touchard, S.; Vega-Gonzalez, A.; Redolfi, M.; Bonnin, X.; Hassouni, K.; Duten, X. 2012-08-01 This paper reports the results obtained for the degradation of acetaldehyde by an atmospheric plasma corona discharge working in a pulsed regime. It was shown that a few hundred ppm of acetaldehyde diluted in a pure N2 gas flow can be removed up to 80% by a discharge fed with an electric power lower than 1 W. Under the same conditions, adding up to 5% of O2 allowed the removal of up to 95% of the initial acetaldehyde. The main identified end products were CO2, CO and methanol. A quasi-homogeneous zero-dimensional chemical model was developed to investigate the respective efficiency of the discharge and post-discharge periods in the global removal of the pollutant. The identified main pathways of acetaldehyde degradation were quenching of N2 metastable states during plasma pulses and oxidation by O and OH radicals during the post-discharge. This latter contribution increased with input power because of ozone accumulation in the gas mixture acting as an additional oxygen reservoir. 18. Vanillic and syringic acids from biomass burning: Behaviour during Fenton-like oxidation in atmospheric aqueous phase and in the absence of light. Science.gov (United States) Santos, Gabriela T A D; Santos, Patrícia S M; Duarte, Armando C 2016-08-01 Biomass combustion is a threat to the environment since it emits to the atmosphere organic compounds, which may react and originate others more aggressive. This work studied the behaviours of vanillic and syringic acids, small aromatic tracers of biomass burning, during Fenton-like oxidation in aqueous phase and absence of light. For both compounds, the extent of oxidation increased with pH decrease from neutral to acid in atmospheric waters, but for vanillic acid the neutral pH was not able of promoting the oxidation. With the oxidation of both acids were formed chromophoric compounds, and the formation rate increased with the degree of electron-donator substituents in benzene ring. The initial and produced compounds were not totally degraded up to 24h of reaction at pH 4.5, suggesting that the night period may be not sufficient for their full degradation in atmospheric waters. The major compounds formed were the 3,4-dihydroxybenzoic acid for vanillic acid, and the 1,4-dihydroxy-2,6-dimethoxybenzene for syringic acid. These findings suggest the occurrence of an ipso attack by the hydroxyl radical preferential to the methoxy and carboxyl groups of vanillic and syringic acids, respectively. It is important to highlight that for both aromatic acids the main compounds produced are also small aromatic compounds. PMID:27085101 19. Partial conductivities in perovskites CaZr1- x Sc x O3-α ( x = 0.03-0.20) in an oxidation atmosphere Science.gov (United States) Gorelov, V. P.; Balakireva, V. B.; Kuz'min, A. V. 2016-01-01 Partial (ionic, proton, and hole) conductivities of oxides CaZr1- x Sc x O3-α( x = 0.03-0.20) with the perovskite structure in air atmosphere have been studied as functions of temperature in the range of 600-900°C and partial water-vapor pressure in the range of {P_{{H_2}O}}= 40-2500 Pa. The influence of the humidity of the atmosphere on the relative change in the concentration of oxygen vacancies as a function of temperature has been estimated. 20. Photocatalytic Decomposition of Methyl Red Dye by Using Nanosized Zinc Oxide Deposited on Glass Beads in Various pH and Various Atmosphere Directory of Open Access Journals (Sweden) H. R. Ebrahimi 2013-01-01 Full Text Available Photocatalytic decomposition of methyl red (MR as a pollutant in wastewater samples is investigated in this study. This photodegradation was investigated in water in neutral, alkaline, and acidic media under external UV light irradiation by zinc oxide nanosized catalysts on granule glass. The effect of four atmosphere types including air, nitrogen, oxygen, and argon was investigated. Finally, it was found that photodecomposition using nanosized ZnO layered on glass is a new alternative route for efficient wastewater treatment. The results showed that the titled dye is degraded by various rate under different atmosphere and pH. 1. The magnetic and oxidation behavior of bare and silica-coated iron oxide nanoparticles synthesized by reverse co-precipitation of ferrous ion (Fe{sup 2+}) in ambient atmosphere Energy Technology Data Exchange (ETDEWEB) Mahmed, N., E-mail: norsuria.mahmed@aalto.fi [Aalto University School of Chemical Technology, Department of Materials Science and Engineering, P.O. Box 16200, FI-00076 Aalto (Finland); School of Materials Engineering, Kompleks Pusat Pengajian UniMAP, Taman Muhibbah, Universiti Malaysia Perlis, 02600 Jejawi, Perlis (Malaysia); Heczko, O., E-mail: heczko@fzu.cz [Institute of Physics, Academy of Sciences, Czech Republic Na Slovance 2, CZ-182 21 Praha 8 (Czech Republic); Lancok, A., E-mail: Lancok@seznam.cz [Institute of Physics, Academy of Sciences, Czech Republic Na Slovance 2, CZ-182 21 Praha 8 (Czech Republic); Hannula, S-P., E-mail: simo-pekka.hannula@aalto.fi [Aalto University School of Chemical Technology, Department of Materials Science and Engineering, P.O. Box 16200, FI-00076 Aalto (Finland) 2014-03-15 The synthesis of iron oxide nanoparticles, i.e., magnetite was attempted by using only ferrous ion (Fe{sup 2+}) as a magnetite precursor, under an ambient atmosphere. The room temperature reverse co-precipitation method was used, by applying two synthesis protocols. The freshly prepared iron oxide was also immediately coated with Stöber silica (SiO{sub 2}) layer, forming the coreshell structure. The phase, stoichiometry, crystallite and the particle size of the synthesized powders were determined by using X-ray diffraction (XRD) and transmission electron microscope (TEM), while the magnetic and oxidation behaviors were studied by using the vibrating sample magnetometer (VSM) and Mössbauer spectroscopy. Based on the results, the bare iron oxide nanoparticles are in the stoichiometry between the magnetite and the maghemite stoichiometry, i.e., oxidation occurs. This oxidation is depending on the synthesis protocols used. With the silica coating, the oxidation can be prevented, as suggested by the fits of Mössbauer spectra and low temperature magnetic measurement. - Highlights: • Synthesis of magnetite was attempted by using ferrous ion (Fe{sup 2+}) in air. • The synthesized particle has a stoichiometry in between magnetite and maghemite. • Silica shell partly prevented the oxidation as suggested by magnetic and Mössbauer study. 2. Non-OH chemistry in oxidation flow reactors for the study of atmospheric chemistry systematically examined by modeling Science.gov (United States) Peng, Zhe; Day, Douglas A.; Ortega, Amber M.; Palm, Brett B.; Hu, Weiwei; Stark, Harald; Li, Rui; Tsigaridis, Kostas; Brune, William H.; Jimenez, Jose L. 2016-04-01 Oxidation flow reactors (OFRs) using low-pressure Hg lamp emission at 185 and 254 nm produce OH radicals efficiently and are widely used in atmospheric chemistry and other fields. However, knowledge of detailed OFR chemistry is limited, allowing speculation in the literature about whether some non-OH reactants, including several not relevant for tropospheric chemistry, may play an important role in these OFRs. These non-OH reactants are UV radiation, O(1D), O(3P), and O3. In this study, we investigate the relative importance of other reactants to OH for the fate of reactant species in OFR under a wide range of conditions via box modeling. The relative importance of non-OH species is less sensitive to UV light intensity than to water vapor mixing ratio (H2O) and external OH reactivity (OHRext), as both non-OH reactants and OH scale roughly proportionally to UV intensity. We show that for field studies in forested regions and also the urban area of Los Angeles, reactants of atmospheric interest are predominantly consumed by OH. We find that O(1D), O(3P), and O3 have relative contributions to volatile organic compound (VOC) consumption that are similar or lower than in the troposphere. The impact of O atoms can be neglected under most conditions in both OFR and troposphere. We define "riskier OFR conditions" as those with either low H2O ( 200 s-1 in OFR254). We strongly suggest avoiding such conditions as the importance of non-OH reactants can be substantial for the most sensitive species, although OH may still dominate under some riskier conditions, depending on the species present. Photolysis at non-tropospheric wavelengths (185 and 254 nm) may play a significant (> 20 %) role in the degradation of some aromatics, as well as some oxidation intermediates, under riskier reactor conditions, if the quantum yields are high. Under riskier conditions, some biogenics can have substantial destructions by O3, similarly to the troposphere. Working under low O2 (volume mixing 3. Methane and nitrous oxide measurements onboard the UK Atmospheric Research Aircraft using quantum cascade laser spectrometry (QCL) Science.gov (United States) Muller, J. B.; O'Shea, S.; Dorsey, J.; Bauguitte, S.; Cain, M.; Allen, G.; Percival, C. J.; Gallagher, M. W. 2012-12-01 A Aerodyne Research© Mini-Quantum Cascade Laser (QCL) spectrometer was installed on the UK Facility of Airborne Atmospheric Measurements (FAAM) BAe-146 research aircraft and employed during summer 2012. Methane (CH4) and nitrous oxide (N2O) concentrations were measured within the Arctic Circle as part of the MAMM project (Methane and other greenhouse gases in the Arctic - Measurements, process studies and Modelling) as well as around the UK as part of the ClearfLo project (Clean Air for London). A range of missions were flown, including deep vertical profiles up to the stratosphere, providing concentration profiles of CH4 and N2O, as well as low altitude level runs exploring near surface diffuse emission sources such as the wetlands in Arctic Lapland and point emissions sources such as gas platforms off the UK coast. Significant pollution plumes were observed both in the Arctic and around the UK with elevated CH4 concentrations, as well as enhanced CO, O3 and aerosol levels. The NAME Lagrangian particle dispersion model will be used to investigate the origins of these CH4 plumes to identify the locations of the emissions sources. The first set of flights using QCL on the FAAM research aircraft have been successful and regular in-flight calibrations (high/low span) and target concentrations were used to determine instrument accuracy and precision. Additional data quality control checks could be made by comparison with an onboard Los Gatos Fast Greenhouse Gas Analyser (FGGA) for CO2 and CH4 and provide the basis for further instrument development and implementation for future Arctic MAMM flights during spring and summer 2013. 4. Atmospheric oxidation and antioxidants CERN Document Server Meurant, Gerard 1993-01-01 Volume I reviews current understanding of autoxidation, largely on the basis of the reactions of oxygen with characterised chemicals. From this flows the modern mechanism of antioxidant actions and their application in stabilisation technology. 5. Atmospheric reactivity of hydroxyl radicals with guaiacol (2-methoxyphenol), a biomass burning emitted compound: Secondary organic aerosol formation and gas-phase oxidation products Science.gov (United States) Lauraguais, Amélie; Coeur-Tourneur, Cécile; Cassez, Andy; Deboudt, Karine; Fourmentin, Marc; Choël, Marie 2014-04-01 Methoxyphenols are low molecular weight semi-volatile polar aromatic compounds produced from the pyrolysis of wood lignin. The reaction of guaiacol (2-methoxyphenol) with hydroxyl radicals has been studied in the LPCA simulation chamber at (294 ± 2) K, atmospheric pressure, low relative humidity (RH Flame Ionization Detection) and GC-MS (Gas Chromatography - Mass Spectrometry) analysis show the formation of nitroguaiacol isomers as main oxidation products in the gas- and aerosol-phases. In the gas-phase, the formation yields were (10 ± 2) % for 4-nitroguaiacol (1-hydroxy-2-methoxy-4-nitrobenzene; 4-NG) and (6 ± 2) % for 3- or 6-nitroguaiacol (1-hydroxy-2-methoxy-3-nitrobenzene or 1-hydroxy-2-methoxy-6-nitrobenzene; 3/6-NG; the standards are not commercially available so both isomers cannot be distinguished) whereas in SOA their yield were much lower (≤0.1%). To our knowledge, this work represents the first identification of nitroguaiacols as gaseous oxidation products of the OH reaction with guaiacol. As the reactivity of nitroguaiacols with atmospheric oxidants is probably low, we suggest using them as biomass burning emission gas tracers. The atmospheric implications of the guaiacol + OH reaction are also discussed. 6. Data on the identification and characterization of by-products from N-Cbz-3-aminopropanal and t-BuOOH/H2O2 chemical reaction in chloroperoxidase-catalyzed oxidations. Science.gov (United States) Masdeu, Gerard; Pérez-Trujillo, Míriam; López-Santín, Josep; Álvaro, Gregorio 2016-09-01 This data article is related to the subject of a publication in Process Biochemistry, entitled "Chloroperoxidase-catalyzed amino alcohol oxidation: Substrate specificity and novel strategy for the synthesis of N-Cbz-3-aminopropanal" (Masdeu et al., 2016) [1]. Here, the products of the chemical reaction involving the amino aldehyde (N-Cbz-3-aminopropanal) and peroxides (tert-butyl hydroperoxide and H2O2) are characterized by NMR. (1)H and (13)C NMR full characterization of the products was obtained based on 2D NMR, 1D selective NOESY and diffusion spectroscopy (DOSY) experiments. PMID:27437440 7. Nitrous oxide in the Changjiang (Yangtze River Estuary and its adjacent marine area: Riverine input, sediment release and atmospheric fluxes Directory of Open Access Journals (Sweden) G.-L. Zhang 2010-11-01 Full Text Available Dissolved nitrous oxide (N2O was measured in the waters of the Changjiang (Yangtze River Estuary and its adjacent marine area during five surveys covering the period of 2002–2006. Dissolved N2O concentrations ranged from 6.04 to 21.3 nM, and indicate great temporal and spatial variations. Distribution of N2O in the Changjiang Estuary was influenced by multiple factors and the key factor varied between cruises. Dissolved riverine N2O was observed monthly at station Xuliujing of the Changjiang, and ranged from 12.4 to 33.3 nM with an average of 19.4 ± 7.3 nM. N2O concentrations in the river waters showed obvious seasonal variations with higher values occurring in both summer and winter. Annual input of N2O from the Changjiang to the estuary was estimated to be 15.0 × 106 mol/yr. N2O emission rates from the sediments of the Changjiang Estuary in spring ranged from −1.88 to 2.02 μmol m−2 d−1, which suggests that sediment can act as either a source or a sink of N2O in the Changjiang Estuary. Average annual sea-to-air N2O fluxes from the studied area were estimated to be 7.7 ± 5.5, 15.1 ± 10.8 and 17.0 ± 12.6 μmol m−2d−1 using LM86, W92 and RC01 relationships, respectively. Hence the Changjiang Estuary and its adjacent marine area are a net source of atmospheric N2O. 8. Influence of NO2 and metal ions on oxidation of aqueous-phase S(IV in atmospheric concentrations Directory of Open Access Journals (Sweden) Cláudia R. Martins 2008-06-01 Full Text Available An investigation was made of the influence of atmospheric concentrations (15 or 130 ppbv of NO2 on the aqueous-phase oxidation rate of S(IV in the presence and absence of Fe(III, Mn(II and Cr(VI metal ions under controlled experimental conditions (pH, T, concentration of reactants, etc.. The reaction rate in the presence of the NO2 flow was slower than the reaction rate using only clean air with an initial S(IV concentration of 10-4 mol/L. NO2 appears to react with S(IV, producing a kind of inhibitor that slows down the reaction. Conversely, tenfold lower concentrations of S(IV ([S(IV]º = 10-5 mol/L caused a faster reaction in the presence of NO2 than the reaction using purified air. Under these conditions, therefore, the equilibrium shifts to sulfate formation. With the addition of Fe(III, Mn(II or Cr(VI in the presence of a NO2 flow, the reaction occurred faster under all the conditions in which S(IV oxidation was investigated.A reação de oxidação de S(IV em fase aquosa foi estudada em laboratório em presença de NO2 dos íons metálicos Fe(III, Mn(II, e Cr(VI sob condições experimentais controladas (pH, T, concentração dos reagentes, etc.. Na presença de corrente de ar com NO2 (15 ou 130 ppbv a reação de oxidação de S(IV ocorreu mais lentamente do que na presença de ar purificado, para uma concentração inicial de S(IV de 10-4 mol/L. Ao contrário, para concentração inicial de S(IV dez vezes menor ([S(IV]° = 10-5 mol/L a reação ocorreu mais rapidamente na presença de NO2. A explicação está relacionada com o equilíbrio envolvendo a formação de espécies intermediárias de longa vida, que impedem o prosseguimento da reação, porém a depender das concentrações relativas de S(IV e NO2, essas espécies se decompõem deslocando o equilíbrio no sentido de formação de sulfato. A adição dos íons Fe(III, Mn(II ou Cr(VI em presença de corrente de ar com NO2 indicou atividade catalítica para esses íons, em todas 9. A simple way to obtain high saturation magnetization for superparamagnetic iron oxide nanoparticles synthesized in air atmosphere: Optimization by experimental design Science.gov (United States) Karaagac, Oznur; Kockar, Hakan 2016-07-01 Orthogonal design technique was applied to obtain superparamagnetic iron oxide nanoparticles with high saturation magnetization, Ms. Synthesis of the nanoparticles were done in air atmosphere according to the orthogonal table L934. Magnetic properties of the synthesized nanoparticles were measured by a vibrating sample magnetometer. Structural analysis of the nanoparticles was also carried out by X-ray diffraction technique (XRD), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). After the analysis of magnetic data, the optimized experimental parameters were determined as [Fe+2]/[Fe+3]=6/6, iron ion concentration=1500 mM, base concentration=6.7 M and reaction time=2 min. Magnetic results showed that the synthesis carried out according to the optimized conditions gave the highest Ms of 69.83 emu/g for the nanoparticles synthesized in air atmosphere. Magnetic measurements at 10 K and 300 K showed the sample is superparamagnetic at room temperature. Structural analysis by XRD, FTIR and selected area electron diffraction showed that the sample had the inverse spinel crystal structure of iron oxide. The particle size of the optimized sample determined from the TEM image is 7.0±2.2 nm. The results indicated that the Ms of superparamagnetic iron oxide nanoparticles can be optimized by experimental design with the suitable choice of the synthesis parameters. 10. Atmospheric-Pressure DBD Cold Plasma for Preparation of High Active Au/P25 Catalysts for Low-Temperature CO Oxidation Institute of Scientific and Technical Information of China (English) DI Lanbo; ZHAN Zhibin; ZHANG Xiuling; QI Bin; XU Weijie 2016-01-01 Cold plasma generated by dielectric barrier discharge (DBD) at atmospheric pressure was adopted for preparation of commercial TiO2 Degussa P25 supported Au catalysts (Au/P25-P) with the assistance of the deposition-precipitation procedure.The influences of the plasma reduction time and calcination on the performance of the Au/P25-P catalysts were investigated.CO oxidation was performed to investigate the catalytic activity of thc Au/P25 catalysts.The results show that DBD cold plasma for the fabrication of Au/P25-P catalysts is a fast process,and Au/P25-P (4 min) exhibited the highest CO oxidation activity due to the complete reduction of Au compounds and less consumption of oxygen vacancies.In order to form more oxygen vacancies active species,Au/P25-P was calcined to obtain Au/P25-PC catalysts.Interestingly,Au/P25-PC exhibited the highest activity for CO oxidation among the Au/P25 samples.The results of transmission electron microscopy (TEM) indicated that the smaller size and high distribution of Au nanoparticles are the mean reasons for a high performance of Au/P25-PC.Atmospheric-pressure DBD cold plasma was proved to be of great efficiency in preparing high performance supported Au catalysts. Energy Technology Data Exchange (ETDEWEB) Rodney Andrews; Aurora Rubel; Jack Groppo; Ari Geertsema; Frank Huggins; M. Mercedes Maroto-Valer; Brandie M. Markley; Harold Schobert 2006-02-01 With the recent passing of new legislation designed to permanently cap and reduce mercury emissions from coal-fired utilities, it is more important than ever to develop and improve upon methods of controlling mercury emissions. One promising technique is carbon sorbent injection into the flue gas of the coal-fired power plant. Currently, this technology is very expensive as costly commercially activated carbons are used as sorbents. There is also a significant lack of understanding of the interaction between mercury vapor and the carbon sorbent, which adds to the difficulty of predicting the amount of sorbent needed for specific plant configurations. Due to its inherent porosity and adsorption properties as well as on-site availability, carbons derived from gasifiers are potential mercury sorbent candidates. Furthermore, because of the increasing restricted use of landfilling, the coal industry is very interested in finding uses for these materials as an alternative to the current disposal practice. The results of laboratory investigations and supporting technical assessments conducted under DOE Subcontract No. DE-FG26-03NT41795 are reported for the period September 1, 2004 to August 31, 2005. This contract is with the University of Kentucky Research Foundation, which supports work with the University of Kentucky Center for Applied Energy Research and The Pennsylvania State University Energy Institute. The worked described was part of a project entitled ''Advanced Gasification By-Product Utilization''. This work involves the development of technologies for the separation and characterization of coal gasification slags from operating gasification units, activation of these materials to increase mercury and nitrogen oxide capture efficiency, assessment of these materials as sorbents for mercury and nitrogen oxides, and characterization of these materials for use as polymer fillers. 12. Timing and characterization of the change in the redox state of uranium in Precambrian surface environments: A proxy for the oxidation state of the atmosphere Science.gov (United States) Pollack, Gerald D. The redox-sensitive geochemical behavior of uranium permits the use of Th/U ratios as a geochemical proxy for the oxidation state of the atmosphere and oceans during sedimentary processes. Due to the effects of post-depositional uranium mobility on Th/U ratios during events involving oxygenated fluids, direct measurements of Th/U ratios are often misleading, but the whole rock Pb isotope composition may be used to determine a sample's apparent time-integrated Th/U ratio (kappaa) and the timing associated with the onset of the U-Th-Pb geochemistry. Rare earth element (REE) concentrations were determined by isotope dilution mass spectrometry to evaluate the influence of multiple provenance components and potential mobility of Th, U, and Pb during post-depositional processes on the Th/U ratio. The Pb isotope compositions and REE concentrations were determined for six Paleoproterozoic sedimentary sequences, which were the focus of previous studies involving the timing of the rise of atmospheric oxygen. The Mount McRae Shale, Huronian Supergroup, and Zaonezhskaya Formation have been interpreted as experiencing post-depositional alteration (perhaps associated with orogenic events) due to Pb-Pb ages that are younger than the likely depositional age and observed fractionation of REE in chondrite normalized REE patterns and interelement REE ratios (e.g. La/Nd, La/Yb, Eu/Eu*). Similar geochemical proxies have been interpreted as sedimentary geochemical features of the Timeball Hill Formation, Hotazel Formation, and Sengoma Argillite Formation. This study of Paleoproterozoic sedimentary units constrains the onset of U-Th decoupling, most likely due to the onset of oxidative weathering conditions, began by 2.32 Ga, the latest. Index words. Pb isotopes, Rare earth elements, Th/U ratios, Time-integrated, Atmospheric evolution, Oxygen content of the atmosphere, U-Th decoupling 13. Poisoning of noble metal catalysts by arsenic and silicon compounds in an oxidizing atmosphere. Die Vergiftung von Edelmetall-Katalysatoren durch Arsen- und Siliziumverbindungen unter oxidierenden Verbindungen Energy Technology Data Exchange (ETDEWEB) Kaizik, A. 1984-01-12 The dissertation deals with the poisoning of noble metal catalysts by arsenic and silicon compounds in an oxidizing atmosphere. The problem was studied in the field of catalytic exhaust and waste air post-combustion, but the findings can be applied to other catalytic processes in which arsenic and silicon compounds may occur as catalyst poisons. The following issues were investigated: 1. Kinetics of arsenic and silicon poisoning of platinum-containing carrier catalysts; 2. Regeneration of poisoned catalysts; 3. mathematical modelling of the poisoning processes. 14. Electrical and optical properties of thin indium tin oxide films produced by pulsed laser ablation in oxygen or rare gas atmospheres DEFF Research Database (Denmark) Thestrup, B.; Schou, Jørgen; Nordskov, A.; 1999-01-01 Films of indium tin oxide (ITO) have been produced in different background gases by pulsed laser deposition (PLD). The Films deposited in rare gas atmospheres on room temperature substrates were metallic, electrically conductive, but had poor transmission of visible light. For substrate...... temperatures at 200 degrees C, the specific resistivity was reduced and the transmission of visible light enhanced for all background gases. Films produced in oxygen turned out to be superior to films deposited in other gases at the same temperature. (C) 1999 Elsevier Science B.V. All rights reserved.... 15. An investigation into the optimum thickness of titanium dioxide thin films synthesized by using atmospheric pressure chemical vapour deposition for use in photocatalytic water oxidation. Science.gov (United States) Hyett, Geoffrey; Darr, Jawwad A; Mills, Andrew; Parkin, Ivan P 2010-09-10 Twenty eight films of titanium dioxide of varying thickness were synthesised by using atmospheric pressure chemical vapour deposition (CVD) of titanium(IV) chloride and ethyl acetate onto glass and titanium substrates. Fixed reaction conditions at a substrate temperature of 660 °C were used for all depositions, with varying deposition times of 5-60 seconds used to control the thickness of the samples. A sacrificial electron acceptor system composed of alkaline sodium persulfate was used to determine the rate at which these films could photo-oxidise water in the presence of 365 nm light. The results of this work showed that the optimum thickness for CVD films on titanium substrates for the purposes of water oxidation was ≈200 nm, and that a platinum coating on the reverse of such samples leads to a five-fold increase in the observed rate of water oxidation. PMID:20645333 16. Oxidative capacity and radical chemistry in the polluted atmosphere of Hong Kong and Pearl River Delta region: analysis of a severe photochemical smog episode Science.gov (United States) Xue, Likun; Gu, Rongrong; Wang, Tao; Wang, Xinfeng; Saunders, Sandra; Blake, Donald; Louie, Peter K. K.; Luk, Connie W. Y.; Simpson, Isobel; Xu, Zheng; Wang, Zhe; Gao, Yuan; Lee, Shuncheng; Mellouki, Abdelwahid; Wang, Wenxing 2016-08-01 We analyze a photochemical smog episode to understand the oxidative capacity and radical chemistry of the polluted atmosphere in Hong Kong and the Pearl River Delta (PRD) region. A photochemical box model based on the Master Chemical Mechanism (MCM v3.2) is constrained by an intensive set of field observations to elucidate the budgets of ROx (ROx = OH+HO2+RO2) and NO3 radicals. Highly abundant radical precursors (i.e. O3, HONO and carbonyls), nitrogen oxides (NOx) and volatile organic compounds (VOCs) facilitate strong production and efficient recycling of ROx radicals. The OH reactivity is dominated by oxygenated VOCs (OVOCs), followed by aromatics, alkenes and alkanes. Photolysis of OVOCs (except for formaldehyde) is the dominant primary source of ROx with average daytime contributions of 34-47 %. HONO photolysis is the largest contributor to OH and the second-most significant source (19-22 %) of ROx. Other considerable ROx sources include O3 photolysis (11-20 %), formaldehyde photolysis (10-16 %), and ozonolysis reactions of unsaturated VOCs (3.9-6.2 %). In one case when solar irradiation was attenuated, possibly by the high aerosol loadings, NO3 became an important oxidant and the NO3-initiated VOC oxidation presented another significant ROx source (6.2 %) even during daytime. This study suggests the possible impacts of daytime NO3 chemistry in the polluted atmospheres under conditions with the co-existence of abundant O3, NO2, VOCs and aerosols, and also provides new insights into the radical chemistry that essentially drives the formation of photochemical smog in the high-NOx environment of Hong Kong and the PRD region. 17. Atmospheric nitric oxide and ozone at the WAIS Divide deep coring site: a discussion of local sources and transport in West Antarctica Science.gov (United States) Masclin, S.; Frey, M. M.; Rogge, W. F.; Bales, R. C. 2013-09-01 The first measurements of atmospheric nitric oxide (NO) along with observations of ozone (O3), hydroperoxides (H2O2 and MHP) and snow nitrate (NO3-) on the West Antarctic Ice Sheet (WAIS) were carried out at the WAIS Divide deep ice-coring site between 10 December 2008 and 11 January 2009. Average ±1σ mixing ratios of NO were 19 ± 31 pptv and confirmed prior model estimates for the summer boundary layer above WAIS. Mean ±1σ mixing ratios of O3 of 14 ± 4 ppbv were in the range of previous measurements from overland traverses across WAIS during summer, while average ±1σ concentrations of H2O2 and MHP revealed higher levels with mixing ratios of 743 ± 362 and 519 ± 238 pptv, respectively. An upper limit for daily average NO2 and NO emission fluxes from snow of 8.6 × 108 and 33.9 × 108 molecule cm-2 s-1, respectively, were estimated based on photolysis of measured NO3- and nitrite (NO2-) in the surface snowpack. The resulting high NOx emission flux may explain the little preservation of NO3- in snow (~ 30%) when compared to Summit, Greenland (75-93%). Assuming rapid and complete mixing into the overlying atmosphere, and steady state of NOx, these snow emissions are equivalent to an average (range) production of atmospheric NOx of 30 (21-566) pptv h-1 for a typical atmospheric boundary-layer depth of 250 (354-13) m. These upper bounds indicate that local emissions from the snowpack are a significant source of short-lived nitrogen oxides above the inner WAIS. The net O3 production of 0.8 ppbv day-1 triggered with NO higher than 2 pptv is too small to explain the observed O3 variability. Thus, the origins of the air masses reaching WAIS Divide during this campaign were investigated with a 4-day back-trajectory analysis every 4 h. The resulting 168 back trajectories revealed that in 75% of all runs air originated from the Antarctic coastal slopes (58%) and the inner WAIS (17%). For these air sources O3 levels were on average 13 ± 3 ppbv. The remaining 25% are 18. Atmospheric nitric oxide and ozone at the WAIS Divide deep coring site: a discussion of local sources and transport in West Antarctica Directory of Open Access Journals (Sweden) S. Masclin 2013-09-01 Full Text Available The first measurements of atmospheric nitric oxide (NO along with observations of ozone (O3, hydroperoxides (H2O2 and MHP and snow nitrate (NO3– on the West Antarctic Ice Sheet (WAIS were carried out at the WAIS Divide deep ice-coring site between 10 December 2008 and 11 January 2009. Average ±1σ mixing ratios of NO were 19 ± 31 pptv and confirmed prior model estimates for the summer boundary layer above WAIS. Mean ±1σ mixing ratios of O3 of 14 ± 4 ppbv were in the range of previous measurements from overland traverses across WAIS during summer, while average ±1σ concentrations of H2O2 and MHP revealed higher levels with mixing ratios of 743 ± 362 and 519 ± 238 pptv, respectively. An upper limit for daily average NO2 and NO emission fluxes from snow of 8.6 × 108 and 33.9 × 108 molecule cm–2 s–1, respectively, were estimated based on photolysis of measured NO3– and nitrite (NO2– in the surface snowpack. The resulting high NOx emission flux may explain the little preservation of NO3– in snow (~ 30% when compared to Summit, Greenland (75–93%. Assuming rapid and complete mixing into the overlying atmosphere, and steady state of NOx, these snow emissions are equivalent to an average (range production of atmospheric NOx of 30 (21–566 pptv h–1 for a typical atmospheric boundary-layer depth of 250 (354–13 m. These upper bounds indicate that local emissions from the snowpack are a significant source of short-lived nitrogen oxides above the inner WAIS. The net O3 production of 0.8 ppbv day–1 triggered with NO higher than 2 pptv is too small to explain the observed O3 variability. Thus, the origins of the air masses reaching WAIS Divide during this campaign were investigated with a 4-day back-trajectory analysis every 4 h. The resulting 168 back trajectories revealed that in 75% of all runs air originated from the Antarctic coastal slopes (58% and the inner WAIS (17%. For these air sources O3 levels were on average 13 ± 3 19. Anthropogenic emissions of oxidized sulfur and nitrogen into the atmosphere of the former Soviet Union in 1985 and 1990 Energy Technology Data Exchange (ETDEWEB) Ryaboshapko, A.G.; Brukhanov, P.A.; Gromov, S.A.; Proshina, Yu.V; Afinogenova, O.G. [Institute of Global Climate and Ecology, Moscow (Russian Federation) 1996-09-01 Anthropogenic emissions of oxidized sulfur and nitrogen over the former Soviet Union for 1985 and 1990 were calculated on the basis of a combination of bottom-up and top-down` approaches. Sulfur dioxide emissions from combustion of hard coal, brown coal, oil products, natural gas, shale oil, peat, wood as well as from metallurgy, sulfuric acid production, and cement production were estimated. Nitrogen oxides emissions were considered separately for large power plants, small power plants, industrial boilers, residential combustion units, and for transport. The sulfur and nitrogen emissions were spatially distributed over the former Soviet Union with 1 x 1 degree resolution. Data on 721 point sources of sulfur dioxide emissions and on the 242 largest power stations as nitrogen oxides sources were used. The area sources of both sulfur dioxide and nitrogen oxides were distributed according to the population density separately for about 150 administrative units of the former Soviet Union. 63 refs., 19 tabs. 20. Oxidation of metals and alloys in controlled atmospheres using in situ transmission electron microscopy and Auger spectrography Science.gov (United States) Rao, D. B.; Heinemann, K.; Douglass, D. L. 1976-01-01 Single-crystalline thin films of copper were oxidized at an isothermal temperature of 425 C and at an oxygen partial pressure of .005 Torr in situ in a high-resolution electron microscope. The specimens were prepared by epitaxial vapor deposition onto polished 100 and 110 faces of rocksalt and mounted in a hot stage inside an ultra-high-vacuum specimen chamber of the microscope. Large amounts of sulfur, carbon, and oxygen were detected by Auger electron spectroscopy on the surface of the as-received films and were removed in situ by ion-sputter etching immediately prior to the oxidation. The nucleation and growth characteristics of Cu2O on Cu were studied. Results show that neither stacking faults nor dislocations are associated with the Cu2O nucleation sites. The growth of Cu2O nuclei is linear with time. The experimental findings, including results from oxygen dissolution experiments and from repetitive oxidation-reduction-oxidation sequences, fit well into the framework of an oxidation process involving (a) the formation of a surface-charge layer, (b) oxygen saturation in the metal and (c) nucleation, followed by surface diffusion of oxygen and bulk diffusion of copper for lateral and vertical oxide growth, respectively. 1. Is carbon within the global terrestrial biosphere becoming more oxidized? Implications for trends in atmospheric O2 OpenAIRE Randerson, JT; Masiello, CA; Still, CJ; Rahn, T.; POORTER, H.; Field, CB 2006-01-01 Measurements of atmospheric O2 and CO2 concentrations serve as a widely used means to partition global land and ocean carbon sinks. Interpretation of these measurements has assumed that the terrestrial biosphere contributes to changing O2 levels by either expanding or contracting in size, and thus serving as either a carbon sink or source (and conversely as either an oxygen source or sink). Here, we show how changes in atmospheric O2 can also occur if carbon within the terrestrial biosphere b... 2. Surface water and atmospheric carbon dioxide and nitrous oxide observations by shipboard automated gas chromatography: Results from expeditions between 1977 and 1990 Energy Technology Data Exchange (ETDEWEB) Weiss, R.F.; Van Woy, F.A.; Salameh, P.K. (Scripps Institution of Oceanography, La Jolla, CA (United States)); Sepanski, R.J. (Tennessee Univ., Knoxville, TN (United States). Energy, Environment and Resources Center) 1992-12-01 This document presents the results of surface water and atmospheric carbon dioxide (CO[sub 2]) and nitrous oxide (N[sub 2]O) measurements carried out by shipboard gas chromatography over the period 1977--1990. These data include results from 11 different oceanic surveys for a total of 41 expedition legs. Collectively, they represent a globally distributed sampling that includes locations in the Atlantic, Pacific, Indian, and Southern Oceans, as well as the Mediterranean and Red Seas. The measurements were made by an automated high-precision shipboard gas chromatographic system developed during the late 1970s and used extensively over the intervening years. This instrument measures CO[sub 2] by flame ionization after quantitative reaction to methane in a stream of hydrogen. Nitrous oxide is measured by a separate electron capture detector. The chromatographic system measures 196 dry-gas samples a day, divided equally among the atmosphere, gas equilibrated with surface water, a low-range gas standard, and a high-range gas standard. 3. Chlorine dioxide and by-products in water distribution systems OpenAIRE Ferreira, Francisco Cardoso 1991-01-01 Chlorine dioxide is used as both a pre-oxidant and/or a post-disinfectant in several water treatment plants in the United States. Chlorine dioxide is associated with its byproducts chlorite and chlorate. Chlorine dioxide, chlorine, chlori te and chlorate were sampled in four distribution systems where chlorine dioxide is used for disinfection purposes: Charleston, WV, Columbus, GA, New Castle, PA, and Skagit, WA. The fate of chlorine dioxide and its by-products in dist... 4. Morphology and structure evolution of tin-doped indium oxide thin films deposited by radio-frequency magnetron sputtering: The role of the sputtering atmosphere International Nuclear Information System (INIS) The microstructure and morphology evolution of tin-doped indium oxide (ITO) thin films deposited by radio-frequency magnetron sputtering in different sputtering atmospheres were investigated by X-ray diffraction, X-ray reflectivity, and atomic force microscopy. The surface roughness w increases with increasing film thickness df, and exhibits a power law behavior w ∼ dfβ. The roughness decreases with increasing O2 flow, while it increases with increasing H2 flow. The growth exponent β is found to be 0.35, 0.75, and 0.98 for depositions in Ar/10%O2, pure Ar, and Ar/10%H2 atmospheres, respectively. The correlation length ξ increases with film thickness also with a power law according to ξ ∼ dfz with exponents z = 0.36, 0.44, and 0.57 for these three different gas atmospheres, respectively. A combination of local and non-local growth modes in 2 + 1 dimensions is discussed for the ITO growth in this work 5. Transmission electron microscopy on early-stage tin oxide film morphology grown by atmospheric pressure chemical vapor deposition International Nuclear Information System (INIS) Nucleation and morphology development during the early stages of chemical vapor deposition (CVD) processes are believed to be of major importance for the overall film properties. Here, the authors have investigated the nucleation of tin oxide films, comparing different tin precursors (tin tetrachloride (TTC) and monobutyl tin trichloride (MBTC)) and focusing on the effect of methanol addition on the film morphology. Employing electron transparent silicon oxide membranes as substrates and combining transmission electron microscopy (TEM), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) analysis on the same set of samples, we describe a detailed picture of nucleation behavior and film growth during early stages of film formation. Our main conclusion is that methanol addition during deposition acts as surfactant, lowering the surface energy of the substrate and resulting in a higher nucleation grain density. Based on these results, we propose a film growth model based on surface energy to explain morphology differences in tin oxide films resulting from methanol addition. 6. Atmospheric-Pressure DBD Cold Plasma for Preparation of High Active Au/P25 Catalysts for Low-Temperature CO Oxidation Science.gov (United States) Di, Lanbo; Zhan, Zhibin; Zhang, Xiuling; Qi, Bin; Xu, Weijie 2016-05-01 Cold plasma generated by dielectric barrier discharge (DBD) at atmospheric pressure was adopted for preparation of commercial TiO2 Degussa P25 supported Au catalysts (Au/P25-P) with the assistance of the deposition-precipitation procedure. The influences of the plasma reduction time and calcination on the performance of the Au/P25-P catalysts were investigated. CO oxidation was performed to investigate the catalytic activity of the Au/P25 catalysts. The results show that DBD cold plasma for the fabrication of Au/P25-P catalysts is a fast process, and Au/P25-P (4 min) exhibited the highest CO oxidation activity due to the complete reduction of Au compounds and less consumption of oxygen vacancies. In order to form more oxygen vacancies active species, Au/P25-P was calcined to obtain Au/P25-PC catalysts. Interestingly, Au/P25-PC exhibited the highest activity for CO oxidation among the Au/P25 samples. The results of transmission electron microscopy (TEM) indicated that the smaller size and high distribution of Au nanoparticles are the mean reasons for a high performance of Au/P25-PC. Atmospheric-pressure DBD cold plasma was proved to be of great efficiency in preparing high performance supported Au catalysts. supported by National Natural Science Foundation of China (Nos. 11505019, 21173028), the Science and Technology Research Project of Liaoning Provincial Education Department (No. L2013464), the Scientific Research Foundation for the Doctor of Liaoning Province (No. 20131004), and the Dalian Jinzhou New District Science and Technology Plan Project (No. KJCX-ZTPY-2014-0001) 7. Atmospheric chemistry of (CF3)2C=CH2: OH radicals, Cl atoms and O3 rate coefficients, oxidation end-products and IR spectra. Science.gov (United States) Papadimitriou, Vassileios C; Spitieri, Christina S; Papagiannakopoulos, Panos; Cazaunau, Mathieu; Lendar, Maria; Daële, Véronique; Mellouki, Abdelwahid 2015-10-14 The rate coefficients for the gas phase reactions of OH radicals, k1, Cl atoms, k2, and O3, k3, with 3,3,3-trifluoro-2(trifluoromethyl)-1-propene ((CF3)2C=CH2, hexafluoroisobutylene, HFIB) were determined at room temperature and atmospheric pressure employing the relative rate method and using two atmospheric simulation chambers and a static photochemical reactor. OH and Cl rate coefficients obtained by both techniques were indistinguishable, within experimental precision, and the average values were k1 = (7.82 ± 0.55) × 10(-13) cm(3) molecule(-1) s(-1) and k2 = (3.45 ± 0.24) × 10(-11) cm(3) molecule(-1) s(-1), respectively. The quoted uncertainties are at 95% level of confidence and include the estimated systematic uncertainties. An upper limit for the O3 rate coefficient was determined to be k3 global warming potential (GWP) calculations, radiative efficiency (RE) was determined from the measured IR absorption cross-sections and treating HFIB both as long (LLC) and short (SLC) lived compounds, including estimated lifetime dependent factors in the SLC case. The HFIB lifetime was estimated from kinetic measurements considering merely the OH reaction, τOH = 14.8 days and including both OH and Cl chemistry, τeff = 10.3 days. Therefore, GWP(HFIB,OH) and GWP(HFIB,eff) were estimated to be 4.1 (LLC) and 0.6 (SLC), as well as 2.8 (LLC) and 0.3 (SLC) for a hundred year time horizon. Moreover, the estimated photochemical ozone creation potential (ε(POCP)) of HFIB was calculated to be 4.60. Finally, HCHO and (CF3)2C(O) were identified as final oxidation products in both OH- and Cl-initiated oxidation, while HC(O)Cl was additionally observed in the Cl-initiated oxidation. PMID:26372403 8. Atmospheric Photochemistry Science.gov (United States) Massey, Harrie; Potter, A. E. 1961-01-01 The upper atmosphere offers a vast photochemical laboratory free from solid surfaces, so all reactions take place in the gaseous phase. At 30 km altitude the pressure has fallen to about one-hundredth of that at ground level, and we shall, rather arbitrarily, regard the upper atmosphere as beginning at that height. By a little less than 100 km the pressure has fallen to 10(exp -3) mm Hg and is decreasing by a power of ten for every 15 km increase in altitude. Essentially we are concerned then with the photochemistry of a nitrogen-oxygen mixture under low-pressure conditions in which photo-ionization, as well as photodissociation, plays an important part. Account must also be taken of the presence of rare constituents, such as water vapour and its decomposition products, including particularly hydroxyl, oxides of carbon, methane and, strangely enough, sodium, lithium and calcium. Many curious and unfamiliar reactions occur in the upper atmosphere. Some of them are luminescent, causing the atmosphere to emit a dim light called the airglow. Others, between gaseous ions and neutral molecules, are almost a complete mystery at this time. Similar interesting phenomena must occur in other planetary atmospheres, and they might be predicted if sufficient chemical information were available. 9. Experimentation and simulation of tin oxide deposition on glass based on the SnCl4 hydrolysis in an in-line atmospheric pressure chemical vapor deposition reactor International Nuclear Information System (INIS) Tin oxide thin films were deposited on glass substrates in an in-line atmospheric pressure chemical vapor deposition reactor under various conditions, which were numerically simulated using a commercial package. A soda-lime glass sheet was used as a deposition substrate, and SnCl4 and H2O in gas phase were separately supplied as the precursor and the oxidizer, respectively. By assuming that the main chemical reactions followed the Rideal–Eley mechanism, the experimentally determined deposition rates were fitted to obtain the reaction factors needed to describe the deposition process. The role of barrier gas injection for minimizing unwanted surface reaction or particle generation inside of the reactor, and not on the target (glass backplane itself) has been elucidated. Furthermore, the optimal operating conditions for the deposition on glass with the additives such as CH3OH and HF have been investigated. - Highlights: • Tin oxide deposition on glass based on the SnCl4 hydrolysis in an in-line reactor • Simulations using Rideal–Eley mechanism were compared to experimental observations. • Results: activation energy—79.3 kJ/mol and frequency factor—1.93 × 1010 m4/kmol·s • Influences of additives on transmittances, hazes, and electrical resistivities 10. Development of a detailed chemical mechanism (MCMv3.1 for the atmospheric oxidation of aromatic hydrocarbons Directory of Open Access Journals (Sweden) C. Bloss 2004-09-01 Full Text Available The Master Chemical Mechanism has been updated from MCMv3 to MCMv3.1 in order to take into account recent improvements in the understanding of aromatic photo-oxidation. Newly available kinetic and product data from the literature has been incorporated into the mechanism. In particular, the degradation mechanisms for hydroxyarenes have been revised following the observation of high yields of ring-retained products, and product studies of aromatic oxidation under relatively low NOx conditions have provided new information on the branching ratios to first generation products. Experiments have been carried out at the European Photoreactor (EUPHORE to investigate key subsets of the toluene system. These results have been used to test our understanding of toluene oxidation, and where possible, refine the degradation mechanisms. The evaluation of MCMv3 and MCMv3.1 using data on benzene, toluene, p-xylene and 1,3,5-trimethylbenzene photosmog systems is described in a companion paper, and significant model shortcomings are identified. Ideas for additional modifications to the mechanisms, and for future experiments to further our knowledge of the details of aromatic photo-oxidation are discussed. 11. Development of a detailed chemical mechanism (MCMv3.1 for the atmospheric oxidation of aromatic hydrocarbons Directory of Open Access Journals (Sweden) C. Bloss 2005-01-01 Full Text Available The Master Chemical Mechanism has been updated from MCMv3 to MCMv3.1 in order to take into account recent improvements in the understanding of aromatic photo-oxidation. Newly available kinetic and product data from the literature have been incorporated into the mechanism. In particular, the degradation mechanisms for hydroxyarenes have been revised following the observation of high yields of ring-retained products, and product studies of aromatic oxidation under relatively low NOx conditions have provided new information on the branching ratios to first generation products. Experiments have been carried out at the European Photoreactor (EUPHORE to investigate key subsets of the toluene system. These results have been used to test our understanding of toluene oxidation, and, where possible, refine the degradation mechanisms. The evaluation of MCMv3 and MCMv3.1 using data on benzene, toluene, p-xylene and 1,3,5-trimethylbenzene photosmog systems is described in a companion paper, and significant model shortcomings are identified. Ideas for additional modifications to the mechanisms, and for future experiments to further our knowledge of the details of aromatic photo-oxidation are discussed. 12. Effect of high-oxygen atmosphere packaging on oxidative stability and sensory quality of two chicken muscles during chill storage DEFF Research Database (Denmark) Jongberg, Sisse; Wen, Jinzhu; Tørngren, Mari Ann; 2014-01-01 of secondary lipid oxidation products. However, while breast stored in MAP-O clearly scored lower in tenderness and higher in rancidity compared to breast in non-oxygen storage, the effect of MAP-O for the sensory quality of thigh was negligible. These results show that thigh is more suitable for storage... 13. Induced apoptosis in melanocytes cancer cell and oxidation in biomolecules through deuterium oxide generated from atmospheric pressure non-thermal plasma jet OpenAIRE Kumar, Naresh; Attri, Pankaj; Yadav, Dharmendra Kumar; Choi, Jinsung; Choi, Eun Ha; Uhm, Han Sup 2014-01-01 Recently, atmospheric-pressure non-thermal plasma-jets (APPJ) are being for the cancer treatment. However, APPJ still has drawbacks such as efficiency and rise in temperature after treatment. So, in this work, a synergetic agent D2O vapour is attached to APPJ which not only increase the efficiency of plasma source against cancer treatment, but also controlled the temperature during the treatment. OD generated by the combination of D2O + N2 plasma helped in enhancing the efficiency of APPJ. We... 14. Flame spray synthesis under a non-oxidizing atmosphere: Preparation of metallic bismuth nanoparticles and nanocrystalline bulk bismuth metal Energy Technology Data Exchange (ETDEWEB) Grass, Robert N.; Stark, Wendelin J. [Institute for Chemical and Bioengineering, ETH Zuerich (Switzerland)], E-mail: wendelin.stark@chem.ethz.ch 2006-10-15 Metallic bismuth nanoparticles of over 98% purity were prepared by a modified flame spray synthesis method in an inert atmosphere by oxygen-deficient combustion of a bismuth-carboxylate based precursor. The samples were characterized by X-ray diffraction, thermal analysis and scanning electron microscopy confirming the formation of pure, crystalline metallic bismuth nanoparticles. Compression of the as-prepared powder resulted in highly dense, nanocrystalline pills with strong electrical conductivity and bright metallic gloss. 15. Latitudinal and Altitudinal Distribution of Carbon Dioxide, Halocarbons, Nitrous Oxide, Methane, Carbon Monoxide and Hydroxyl in the Atmosphere OpenAIRE Kroeze, C. 1992-01-01 Due to human activities, atmospheric concentrations of several gases have been increasing during the past century. Some of these gases are so-called greenhouse gases and play an important role in the earth's climate. Increasing concentrations of greenhouse gases may ultimately result in global climate change. In order to investigate regional effects of the enhanced greenhouse effect, 1- to 3-dimensional computer simulation models are being developed. For the calculation of radiative transfer ... 16. Investigation of the influence of inert and oxidizing atmospheres on the efficiency of decomposition of waste printed circuit boards (WPCBs) Science.gov (United States) Kumari, Anjan; Jha, Manis Kumar; Singh, Rajendra Prasad; Ranganathan, S. 2016-08-01 Thermo-gravimetry was used for studying the influence of the furnace atmosphere during the pyrolysis waste circuit boards (WPCBs). Pyrolysis in argon atmosphere resulted in a continuous decrease of mass of the sample. Rapid mass loss occurred at about 573 K. Heating the WPCBs in air and oxygen atmospheres resulted in an increase in the mass of the sample in the early stages until rapid mass loss occurred at about 573 K. When pyrolysis of larger sample mass (about 5 g each) was carried out in tubular furnace, about 20.43 % mass loss was observed during the pyrolysis of WPCBs in a flowing stream of argon at 548 K during a period of 4 min. On the other hand, a maximum of about 2.26 % mass loss was recorded when the WPCBs were heated at about 600 K for the same time interval in the still air. The mass transfer during the pyrolysis of WPCBs in flowing stream of inert gas was also modeled. It is found that controlling the flow rate of inert gas and the geometry of the equipment can enhance the rate of mass loss significantly. 17. Atmospheric fate of OH initiated oxidation of terpenes. Reaction mechanism of alpha-pinene degradation and secondary organic aerosol formation. Science.gov (United States) Librando, Vito; Tringali, Giuseppe 2005-05-01 This paper studies the reaction products of alpha-pinene, beta-pinene, sabinene, 3-carene and limonene with OH radicals and of alpha-pinene with ozone using FT-IR spectroscopy for measuring gas phase products and HPLC-MS-MS to measure products in the aerosol phase. These techniques were used to investigate the secondary organic aerosol (SOA) formation from the terpenes. The gas phase reaction products were all quantified using reference compounds. At low terpene concentrations (0.9-2.1 ppm), the molar yields of gas phase reaction products were: HCHO 16-92%, HCOOH 10-54% (OH source: H2O2, 6-25 ppm); HCHO 127-148%, HCOOH 4-6% (OH source: CH3ONO, 5-8 ppm). At high terpene concentrations (4.1-13.2 ppm) the results were: HCHO 9-27%, HCOOH 15-23%, CH3(CO)CH3 0-14%, CH3COOH 0-5%, nopinone 24% (only from beta-pinene oxidation), limona ketone 61% (only from limonene oxidation), pinonaldehyde was identified during alpha-pinene degradation (OH source H2O2, 23-30 ppm); HCHO 76-183%, HCOOH 12-15%, CH3(CO)CH3 0-12%, nopinone 17% (from beta-pinene oxidation), limona ketone 48% (from limonene oxidation), pinonaldehyde was identified during alpha-pinene degradation (OH source CH3ONO, 14-16 ppm). Pinic acid, pinonic acid, limonic acid, limoninic acid, 3-caric acid, 3-caronic acid and sabinic acid were identified in the aerosol phase. On the basis of these results, we propose a formation mechanism for pinonic and pinic acid in the aerosol phase explaining how degradation products could influence SOA formation and growth in the troposphere. 18. Methane oxidation in soil profiles of Dutch and Finnish coniferous forests with different soil texture and atmospheric nitrogen deposition NARCIS (Netherlands) Saari, A.; Martikainen, P.J.; Ferm, A.; Ruuskanen, J.; Boer, W. de; Troelstra, S.R.; Laanbroek, H.J. 1997-01-01 We studied methane oxidation capacity in soil profiles of Dutch and Finnish coniferous forests. The Finnish sites (n = 9) had nitrogen depositions from 3 to 36 kg N ha⁻¹ a⁻¹. The deposition of N on the Dutch sites (n = 13) was higher ranging from 50 to 92 kg N ha⁻¹ a⁻¹. The Dutch sites had also lime 19. Influence of thermal treatment in N{sub 2} atmosphere on chemical, microstructural and optical properties of indium tin oxide and nitrogen doped indium tin oxide rf-sputtered thin films Energy Technology Data Exchange (ETDEWEB) Stroescu, H.; Anastasescu, M.; Preda, S.; Nicolescu, M.; Stoica, M. [Institute of Physical Chemistry “Ilie Murgulescu” of the Romanian Academy, Spl. Independentei 202, 060021 Bucharest (Romania); Stefan, N. [National Institute for Lasers, Plasma and Radiation Physics, Atomistilor 409, RO-77125, Bucharest-Magurele (Romania); Kampylafka, V.; Aperathitis, E. [FORTH-IESL, Crete (Greece); Modreanu, M. [Tyndall National Institute, University College Cork, Cork (Ireland); Zaharescu, M. [Institute of Physical Chemistry “Ilie Murgulescu” of the Romanian Academy, Spl. Independentei 202, 060021 Bucharest (Romania); Gartner, M., E-mail: mgartner@icf.ro [Institute of Physical Chemistry “Ilie Murgulescu” of the Romanian Academy, Spl. Independentei 202, 060021 Bucharest (Romania) 2013-08-31 We report the influence of the normal thermal treatment (TT) and of rapid thermal annealing (RTA) on the microstructural, optical and electrical properties of indium tin oxide (ITO) and nitrogen doped indium tin oxide (ITO:N) thin films. The TT was carried out for 1 h at 400 °C and the RTA for 1 min up to 400 °C, both in N{sub 2} atmosphere. The ITO and ITO:N films were deposited by reactive sputtering in Argon, and respectively Nitrogen plasma, on Si with (100) and (111) orientation. The present study brings data about the microstructural and optical properties of ITO thin films with thicknesses around 300–400 nm. Atomic Force Microscopy analysis showed the formation of continuous and homogeneous films, fully covered by quasi-spherical shaped particles, with higher roughness values on Si(100) as compared to Si(111). Spectroscopic ellipsometry allowed the determination of film thickness, optical band gap as well as of the dispersion curves of n and k optical constants. X-ray diffraction analysis revealed the presence of diffraction peaks corresponding to the same nominal bulk composition of ITO, but with different intensities and preferential orientation depending on the substrate, atmosphere of deposition and type of thermal treatment. - Highlights: ► Stability of the films can be monitored by experimental ellipsometric spectra. ► The refractive index of indium tin oxide film on 0.3–30 μm range is reported. ► Si(100) substrate induces rougher film surfaces than Si(111). ► Rapid thermal annealing and normal thermal treatment lead to stable conductive film. ► The samples have a higher preferential orientation after rapid thermal annealing. 20. Atmospheric and Aqueous Deposition of Polycrystalline Metal Oxides Using Mist-CVD for Highly Efficient Inverted Polymer Solar Cells. Science.gov (United States) Zhu, Xiaodan; Kawaharamura, Toshiyuki; Stieg, Adam Z; Biswas, Chandan; Li, Lu; Ma, Zhu; Zurbuchen, Mark A; Pei, Qibing; Wang, Kang L 2015-08-12 Large scale, cost-effective processing of metal oxide thin films is critical for the fabrication of many novel thin film electronics. To date, however, most of the reported solution-based techniques require either extended thermal anneals or additional synthetic steps. Here we report mist chemical vapor deposition as a solution-based, readily scalable, and open-air method to produce high-quality polycrystalline metal oxide thin films. Continuous, smooth, and conformal deposition of metal oxide thin films is achieved by tuning the solvent chemistry of Leidenfrost droplets to promote finer control over the surface-local dissociation process of the atomized zinc-bearing precursors. We demonstrate the deposited ZnO as highly efficient electron transport layers for inverted polymer solar cells to show the power of the approach. A highest efficiency of 8.7% is achieved with a fill factor of 73%, comparable to that of conventional so-gel ZnO, which serves as an indication of the efficient vertical transport and electron collection achievable using this material. PMID:26146797 1. Comparison of nitrous oxide (N2O) analyzers for high-precision measurements of atmospheric mole fractions Science.gov (United States) Lebegue, B.; Schmidt, M.; Ramonet, M.; Wastine, B.; Yver Kwok, C.; Laurent, O.; Belviso, S.; Guemri, A.; Philippon, C.; Smith, J.; Conil, S.; Jost, H. J.; Crosson, E. R. 2015-10-01 Over the last few decades, in-situ measurements of atmospheric N2O mole fractions have been performed using gas chromatographs (GCs) equipped with electron capture detectors (ECDs). When trying to meet the World Meteorological Organization's (WMO) quality goal, this technique becomes very challenging as the detectors are highly non-linear and the GCs at remote stations require a considerable amount of maintenance by qualified technicians to maintain good short-term and long-term repeatability. With more robust optical spectrometers being now available for N2O measurements, we aim to identify a robust and stable analyzer that can be integrated into atmospheric monitoring networks, such as the Integrated Carbon Observation System (ICOS). In this study, we tested seven analyzers that were developed and commercialized from five different companies and compared the results with established techniques. Each instrument was characterized during a time period of approximately eight weeks. The test protocols included the characterization of the short-term and long-term repeatability, drift, temperature dependence, linearity and sensitivity to water vapor. During the test period, ambient air measurements were compared under field conditions at the Gif-sur-Yvette station. All of the analyzers showed a standard deviation better than 0.1 ppb for the 10 min averages. Some analyzers would benefit from improvements in temperature stability to reduce the instrument drift, which could then help in reducing the frequency of calibrations. For most instruments, the water vapor correction algorithms applied by companies are not sufficient for high-precision atmospheric measurements, which results in the need to dry the ambient air prior to analysis. 2. Degradation of polyethylene induced by plasma in oxidizing atmospheres; Degradacion de polietileno inducido por plasma en atmosferas oxidantes Energy Technology Data Exchange (ETDEWEB) Colin, E.; Olayo, M.G.; Cruz, G.J. [Facultad de Quimica, UAEM, Av. Tollocan y Colon, 50000 Toluca (Mexico) 2002-07-01 The garbage of polyethylene is not easily degradable in normal environmental conditions . The indiscriminate use of this polymer and the enormous quantity of garbage which is generated carries a damage to the environment due to its long life as waste. The objective of this work is to study the conditions in which can be carried out the degradation of polyethylene. A form of accelerating the degradation is exposing it to plasma with reactive atmospheres. In this work a study of surface modification of polyethylene by plasmas with discharges of direct current of oxygen and nitrogen is presented. (Author) 3. The role of oxygen and surface reactions in the deposition of silicon oxide like films from HMDSO at atmospheric pressure OpenAIRE Reuter, R; Rügner, K.; Ellerweg, D.; Arcos, T. de los; von Keudell, A.; Benedikt, J 2011-01-01 The deposition of thin SiO$_x$C$_y$H$_z$ or SiO$_x$H$_y$ films by means of atmospheric pressure microplasma jets with admixture of Hexamethyldisiloxane (HMDSO) and oxygen and the role of surface reactions in film growth are investigated. Two types of microplasma jets, one with a planar electrodes and operated in helium gas and the other one with a coaxial geometry operated in argon, are used to study the deposition process. The growth rate of the film and the carbon-content in the film are me... 4. Atmospheric carbon dioxide and its stable isotope ratios, methane, carbon monoxide, nitrous oxide and hydrogen from Shetland Isles Science.gov (United States) Francey, R. J.; Steele, L. P.; Langenfelds, R. L.; Allison, C. E.; Cooper, L. N.; Dunse, B. L.; Bell, B. G.; Murray, T. D.; Tait, H. S.; Thompson, L.; Masarie, K. A. Since November 1992, 0.5 l glass flasks have been filled approximately monthly with dry marine air from Shetland Isles, Scotland (60.2°N, 1.2°W) and transported to CSIRO, Australia for analyses. The Shetland site is part of a CSIRO global flask network with 10-12 sites, anchored to continuous high precision in situ measurements made at the Australian Cape Grim Baseline Station (40.7°S, 144.7°E), a primary station in the Global Atmosphere Watch programme (GAW) coordinated by the World Meteorological Organisation. The methodology is summarised, and Shetland results for CO 2, CH 4, N 2O, CO, H 2 and δ13C, δ18O of CO 2 presented for the period 1992-1996. We compare data to available results from surrounding stations of the NOAA cooperative network (in particular Mace Head, Ireland, 53.3°N, 9.9°W), and address issues of both trace species intercalibration and atmospheric spatial gradients. While considerable uniformity of trace-gas composition is evident in oceanic air over a 13° range of latitude, nevertheless anomalies in CO 2 concentration and isotopic composition are suggested in samples representing air to the west of Shetland. The potential for remotely monitoring integrated emissions from northern Europe is also identified. 5. Microbial ecology of á-Proteobacteria ammonia-oxidizers along a concentration gradient of dry atmospheric nitrogen deposition in the San Bernadino Mountain Range. Science.gov (United States) Jordan, F. L.; Fenn, M. E.; Stein, L. Y. 2002-12-01 The fate of atmospherically-deposited nitrogen from industrial pollution is of major concern in the montane ecosystems bordering the South Coast California Air Basin. Nitrogen deposition rates in the more exposed regions of the San Bernardino Mountains (SBM) are among the highest in North America often exceeding 40 kg ha-1 year-1 in throughfall deposition of nitrate and ammonium (Fenn and Poth, 1999). Forest ecosystems with elevated N deposition generally exhibit elevated accumulation of soil nitrate, leaching and runoff, elevated emissions of nitrogenous gases, increased nitrification, and decreased litter decomposition rates. The role of nitrifying microbial populations, especially those taxonomically associated with the beta-Proteobacteria ammonia-oxidizers (AOB), will provide insight into nitrogen-cycling in these extremely N-saturated environments. Using 16S ribosomal DNA-based molecular techniques (16S rDNA clone library construction and Restriction Fragment Length Polymorphism), we are comparing AOB community diversity at 3 different locations along a natural atmospheric N-deposition concentration gradient in the SBM: from high at Camp Paviaka (CP), medium at Strawberry Peak (SP) to low at Dogwood (DW). As observed for wet N-deposition systems on the east coast, we hypothesized a negative correlation between AOB community diversity, abundance and function with nitrogen loading in the dry N deposition system of SBM. Nitrification potentials determined for the 3 sites along the N-deposition gradient were in the order of CP less than SP less than DW. Preliminary results indicate no correlation between diversity of AOB and increased nitrogen loading. Shannon-Weiner diversity indices calculated for ammonia-oxidizer RFLP group units were 2.22, 2.66 and 1.80 for CP, SP and DW, respectively. 6. Size effects in the thermal conductivity of gallium oxide (β-Ga2O3) films grown via open-atmosphere annealing of gallium nitride Science.gov (United States) Szwejkowski, Chester J.; Creange, Nicole C.; Sun, Kai; Giri, Ashutosh; Donovan, Brian F.; Constantin, Costel; Hopkins, Patrick E. 2015-02-01 Gallium nitride (GaN) is a widely used semiconductor for high frequency and high power devices due to of its unique electrical properties: a wide band gap, high breakdown field, and high electron mobility. However, thermal management has become a limiting factor regarding efficiency, lifetime, and advancement of GaN devices and GaN-based applications. In this work, we study the thermal conductivity of beta-phase gallium oxide (β-Ga2O3) thin films, a component of typical gate oxides used in such devices. We use time domain thermoreflectance to measure the thermal conductivity of a variety of polycrystalline β-Ga2O3 films of different thicknesses grown via open atmosphere annealing of the surfaces of GaN films on sapphire substrates. We show that the measured effective thermal conductivity of these β-Ga2O3 films can span 1.5 orders of magnitude, increasing with an increased film thickness, which is indicative of the relatively large intrinsic thermal conductivity of the β-Ga2O3 grown via this technique (8.8 ± 3.4 W m-1 K-1) and large mean free paths compared to typical gate dielectrics commonly used in GaN device contacts. By conducting time domain thermoreflectance (TDTR) measurements with different metal transducers (Al, Au, and Au with a Ti wetting layer), we attribute this variation in effective thermal conductivity to a combination of size effects in the β-Ga2O3 film resulting from phonon scattering at the β-Ga2O3/GaN interface and thermal transport across the β-Ga2O3/GaN interface. The measured thermal properties of open atmosphere-grown β-Ga2O3 and its interface with GaN set the stage for thermal engineering of gate contacts in high frequency GaN-based devices. 7. Shrinking of silicon nanocrystals embedded in an amorphous silicon oxide matrix during rapid thermal annealing in a forming gas atmosphere Science.gov (United States) van Sebille, M.; Fusi, A.; Xie, L.; Ali, H.; van Swaaij, R. A. C. M. M.; Leifer, K.; Zeman, M. 2016-09-01 We report the effect of hydrogen on the crystallization process of silicon nanocrystals embedded in a silicon oxide matrix. We show that hydrogen gas during annealing leads to a lower sub-band gap absorption, indicating passivation of defects created during annealing. Samples annealed in pure nitrogen show expected trends according to crystallization theory. Samples annealed in forming gas, however, deviate from this trend. Their crystallinity decreases for increased annealing time. Furthermore, we observe a decrease in the mean nanocrystal size and the size distribution broadens, indicating that hydrogen causes a size reduction of the silicon nanocrystals. 8. UV absorption cross sections of nitrous oxide (N2O and carbon tetrachloride (CCl4 between 210 and 350 K and the atmospheric implications Directory of Open Access Journals (Sweden) C. H. Jackman 2010-07-01 Full Text Available Absorption cross sections of nitrous oxide (N2O and carbon tetrachloride (CCl4 are reported at five atomic UV lines (184.95, 202.548, 206.200, 213.857, and 228.8 nm at temperatures in the range 210–350 K. In addition, UV absorption spectra of CCl4 are reported between 200–235 nm as a function of temperature (225–350 K. The results from this work are critically compared with results from earlier studies. For N2O, the present results are in good agreement with the current JPL recommendation enabling a reduction in the estimated uncertainty in the N2O atmospheric photolysis rate. For CCl4, the present cross section results are systematically greater than the current recommendation at the reduced temperatures most relevant to stratospheric photolysis. The new cross sections result in a 5–7% increase in the modeled CCl4 photolysis loss, and a slight decrease in the stratospheric lifetime, from 51 to 50 years, for present day conditions. The corresponding changes in modeled inorganic chlorine and ozone in the stratosphere are quite small. A CCl4 cross section parameterization for use in atmospheric model calculations is presented. 9. UV absorption cross sections of nitrous oxide (N2O and carbon tetrachloride (CCl4 between 210 and 350 K and the atmospheric implications Directory of Open Access Journals (Sweden) C. H. Jackman 2010-04-01 Full Text Available Absorption cross sections of nitrous oxide (N2O and carbon tetrachloride (CCl4 are reported at five atomic UV lines (184.95, 202.548, 206.200, 213.857, and 228.8 nm at temperatures in the range 210–350 K. In addition, UV absorption spectra of CCl4 are reported between 200–235 nm as a function of temperature (225–350 K. The results from this work are critically compared with results from earlier studies. For N2O, the present results are in good agreement with the current JPL recommendation enabling a reduction in the estimated uncertainty in the N2O atmospheric photolysis rate. For CCl4, the present cross section results are systematically greater than the current recommendation at the reduced temperatures most relevant to stratospheric photolysis. The new cross sections result in a 5–7% increase in the modeled CCl4 photolysis loss, and a slight decrease in the stratospheric lifetime, from 51 to 50 years, for present day conditions. The corresponding changes in modeled inorganic chlorine and ozone in the stratosphere are quite small. A CCl4 cross section parameterization for use in atmospheric model calculations is presented. 10. Deposition of silicon oxide like films from HMDSO by means of atmospheric pressure microplasma jets: Study of deposition mechanisms CERN Document Server Reuter, R; Ellerweg, D; Arcos, T de los; von Keudell, A; Benedikt, J 2011-01-01 The deposition of thin SiOxCyH or SiOxHy films by means of atmospheric pressure microplasma jets with Helium / Hexamethyldisiloxane (HMDSO / O2) mixtures and the role of surface reactions for the film growth have been investigated. The growth rate and the carbon-content in the film are measured as a function of the O2 and HMDSO mixture in the gas flow. Two types of microplasma jets, one with a planar and one with a coaxial geometry, are used to study the deposition process. The very localised deposition on and treatment of the surface gives the opportunity to separate deposition and treatment processes by applying two jets on a rotating substrate. The etching of carbon at the surface and the increasing HMDSO depletion leading to an increasing deposition rate are both induced by admixing oxygen. Carbon free films can be deposited, even without addition of oxygen, and the main loss channels for carbon are surface reactions. 11. Tensile Strength and Oxide Analysis of Carbon Steel in Concrete Exposed in Atmospheric Environment for 53 Years Institute of Scientific and Technical Information of China (English) FENG Xingguo; LU Xiangyu; ZUO Yu; CHEN Da; SU Xiaodong 2015-01-01 The tensile strength of a corroded rebar in a 53-year-old concrete structure was studied. The microstructure of the metallic substrate, the fracture surface, and the corrosion product layers were investigated. Metallographic observation results showed that the carbon steel was constituted of ferrite and some pearlite. The tensile test results indicated that the corroded rebar presented low strength and elongation. In addition, the fracture surface of the rebar in the tensile test displayed dimple fracture behavior. The Raman spectroscopy results indicated that corrosion products at the general corrosion zone were obviously different from those at the localized corrosion zone. The rust layer at the general corrosion zone was composed of goethite (α-FeOOH), magnetite (Fe3O4), and hematite (α-Fe2O3), while that of the pitting zone was made of feroxyhyte (δ-FeOOH), goethite (α-FeOOH), and hematite (α-Fe2O3). However, the general tendencies that the corrosion products were constituted of a mix of oxides and hydroxides, the oxides mainly existed in the internal part and the hydroxides more presented in the external layer were observed. 12. Reproductive toxicology of disinfection by-products. OpenAIRE Smith, M. K.; Zenick, H; George, E L 1986-01-01 The chronic exposure of large segments of the population to disinfected drinking water has necessitated an evaluation of the health effects of the by-products of the chlorination process. This paper reviews the available information concerning the reproductive consequences associated with exposure to disinfection by-products. Four groups of compounds are discussed: the trihalomethanes, in particular chloroform; the chlorinated phenols; chlorinated humic substances; and the haloacetonitriles. ... 13. Ambient atmosphere-processable, printable Cu electrodes for flexible device applications: structural welding on a millisecond timescale of surface oxide-free Cu nanoparticles Science.gov (United States) Oh, Sang-Jin; Jo, Yejin; Lee, Eun Jung; Lee, Sun Sook; Kang, Young Hun; Jeon, Hye-Ji; Cho, Song Yun; Park, Jin-Seong; Seo, Yeong-Hui; Ryu, Beyong-Hwan; Choi, Youngmin; Jeong, Sunho 2015-02-01 Recently, various functional devices based on printing technologies have been of paramount interest, owing to their characteristic processing advantages along with excellent device performance. In particular, printable metallic electrodes have drawn attention in a variety of optoelectronic applications; however, research into printable metallic nanoparticles has been limited mainly to the case of an environmentally stable Ag phase. Despite its earth-abundance and highly conductive nature, the Cu phase, to date, has not been exploited as an ambient atmosphere-processable, printable material due to its critical oxidation problem in air. In this study, we demonstrate a facile route for generating highly conductive, flexible Cu electrodes in air by introducing the well-optimized photonic sintering at a time frame of 10-3 s, at which the photon energy, rather than conventional thermal energy, is instantly provided. It is elucidated here how the surface oxide-free, printed Cu particulate films undergo chemical structural/microstructural evolution depending on the instantly irradiated photon energy, and a successful demonstration is provided of large-area, flexible, printed Cu conductors on various substrates, including polyimide (PI), polyethersulfone (PES), polyethylene terephthalate (PET), and paper. The applicability of the resulting printed Cu electrodes is evaluated via implementation into both flexible capacitor devices and indium-gallium-zinc oxide (IGZO) flexible thin-film transistors.Recently, various functional devices based on printing technologies have been of paramount interest, owing to their characteristic processing advantages along with excellent device performance. In particular, printable metallic electrodes have drawn attention in a variety of optoelectronic applications; however, research into printable metallic nanoparticles has been limited mainly to the case of an environmentally stable Ag phase. Despite its earth-abundance and highly conductive 14. Inductively coupled plasma torch efficiency at atmospheric pressure for organo-chlorine liquid waste removal: Chloroform destruction in oxidative conditions Energy Technology Data Exchange (ETDEWEB) Kamgang-Youbi, Georges, E-mail: kamyougeo@yahoo.fr [French Atomic Commission-CEA, Marcoule-DTCD/SCDV/LPIC, BP 17171, 30207 Bagnols-Sur-Cèze Cedex (France); Department of Inorganic Chemistry, The University of Yaounde I, P.O Box, 812 Yaounde (Cameroon); Poizot, Karine; Lemont, Florent [French Atomic Commission-CEA, Marcoule-DTCD/SCDV/LPIC, BP 17171, 30207 Bagnols-Sur-Cèze Cedex (France) 2013-01-15 Highlights: ► Inductively plasma torch is used for the decomposition of organochlorine molecule. ► We examine the impact of liquid water substitution by oxygen gas as oxidant. ► Complete and safe decomposition is achieved with the presence of oxygen. ► The energy efficiency and capabilities of process are better with O{sub 2} than H{sub 2}O. -- Abstract: The performance of a plasma reactor for the degradation of chlorinated hydrocarbon waste is reported. Chloroform was used as a target for a recently patented destruction process based using an inductive plasma torch. Liquid waste was directly injected axially into the argon plasma with a supplied power of ∼4 kW in the presence of oxygen as oxidant and carrier gas. Decomposition was performed at CHCl{sub 3} feed rates up to 400 g h{sup −1} with different oxygen/waste molar ratios, chloroform destruction was obtained with at least 99% efficiency and the energy efficiency reached 100 g kWh{sup −1}. The conversion end products were identified and assayed by online FTIR spectroscopy (CO{sub 2}, HCl and H{sub 2}O) and redox titration (Cl{sub 2}). Considering phosgene as representative of toxic compounds, only very small quantities of toxics were released (<1 g h{sup −1}) even with high waste feed rates. The experimental results were very close to the equilibrium composition predicted by thermodynamic calculations. At the bottom of the reactor, the chlorinated acids were successfully trapped in a scrubber and transformed into mineral salts, hence, only CO{sub 2} and H{sub 2}O have been found in the final off-gases composition. 15. Quantification of carbon dioxide, methane, nitrous oxide, and chloroform emissions over Ireland from atmospheric observations at Mace Head International Nuclear Information System (INIS) Flux estimates of CO2, CH4, N2O and CHCl3 over Ireland are inferred from continuous atmospheric records of these species. We use radon-222 (222Rn) as a reference compound to estimate unknown sources of other species. The correlation between each species and 222Rn is calculated for a suite of diurnal events that have been selected in the Mace Head record over the period 1995-1997 to represent air masses exposed to sources over Ireland. We established data selection criteria based on 222Rn and 212Pb concentrations. We estimated flux densities of 12x103 kg CH4/km2/yr, 680 kg N2O/km2/yr and 20 kg CHCl3/km2/yr for CH4, N2O and CHCl3, respectively. We also inferred flux densities of 250x103 kg C/km2/yr for CO2 during wintertime, and of 760x103 kg C/km2/yr for CO2 during summer night-time. Our CH4 inferred flux compare well with the CORINAIR90 and CORNAIR94 inventories for Ireland. The N2O emission flux we inferred is close to the inventory value by CORINAIR90, but twice the inventory value by CORINAIR94 and EDGAR 2.0. This discrepancy may have been caused by the use of the revised 1996 IPCC guidelines for national greenhouse gas inventories in 1994, which include a new methodology for N2O emissions from agriculture. We carried out the first estimation of CHCl3 emission fluxes over Ireland. This estimation is 4 times larger than the CHCl3 emission fluxes measured close to the Mace Head station over peatlands. Our CHCl3 emission fluxes estimate is consistent with the interpretation of the same data by Ryall (personal communication, 2000), who obtained, using a Lagrangian atmospheric transport model, CHCl3 fluxes of 24±7 kg CHCl3/km2/yr. Our estimates of CO2 emission fluxes during summer night-time and wintertime are close to those estimated from inventories and to one biogeochemical model of heterotrophic respiration 16. NATURAL ANTIOXIDANT INGREDIENT FROM BY-PRODUCTS OF FRUITS Directory of Open Access Journals (Sweden) G. S. El-Baroty 2014-01-01 used safely in the edible oil industry and cosmetics to delay its oxidation. It can be applied in other food industries as a natural antioxidant instead of synthetic antioxidants. Further study should be carried out to identify the predominant phenolics responsible for the antioxidant activity of by product extracts. 17. Hemodynamic Changes Caused by Exposure of Animals with Acute Immobilization Stress to Continuous Terahertz Radiation with Frequencies equal to Absorption and Emission Frequencies of Nitrogen Oxide and Atmospheric Oxygen Directory of Open Access Journals (Sweden) Vyacheslav F. Kirichuk 2012-12-01 Full Text Available The aim was to study the effects of exposure of albino rats to continuous terahertz radiation with frequencies equal to absorption and emission frequencies of nitrogen oxide (150.176-150.664 GHz and atmospheric oxygen (129.0 ± 0.75 GHz during their immobilization stress on their blood flow rate. Methods – The group of 120 male non-pedigree albino rats with average weight of 180-220 g was chosen as a test subject. Simulation of hemodynamic disorders was achieved by incurring active immobilization stress. All rats were exposed to electromagnetic terahertz radiation equal to absorption and emission frequencies of nitrogen oxide (150.176-150.664 GHz and atmospheric oxygen (129.0 ± 0.75 GHz for 5, 15 and 30 minutes. Results – Experimental simulation of hemodynamic disorders during acute immobilization stress has shown that exposure to continuous terahertz radiation with frequencies equal to absorption and emission frequencies of nitrogen oxide (150.176-150.664 GHz and atmospheric oxygen (129.0 ± 0.75 GHz for 5, 15 and 30 minutes allows to revert post-stress hemodynamic changes in great vessels. Conclusion – This allows using terahertz electromagnetic radiation with frequencies equal to absorption and emission frequencies of nitrogen oxide (150.176-150.664 GHz and atmospheric oxygen (129.0 ± 0.75 GHz to treat hemodynamic disorders accompanying some of pathologic diseases. 18. Control of substrate oxidation in MOD ceramic coating on low-activation ferritic steel with reduced-pressure atmosphere Energy Technology Data Exchange (ETDEWEB) Tanaka, Teruya, E-mail: teru@nifs.ac.jp; Muroga, Takeo 2014-12-15 Highlights: • A Cr{sub 2}O{sub 3} layer was produced on a ferritic steel substrate with a reduced-pressure. • The Cr{sub 2}O{sub 3} layer prevents further substrate oxidation in following coating process. • The Cr{sub 2}O{sub 3} layer has a function as a hydrogen permeation barrier. • A smooth MOD Er{sub 2}O{sub 3} coating was successfully made on the Cr{sub 2}O{sub 3} layer by dip coating. • The Cr{sub 2}O{sub 3} layer would enhance flexibility in MOD coating process and performances. - Abstract: An Er{sub 2}O{sub 3} ceramic coating fabricated using the metal–organic decomposition (MOD) method on a Cr{sub 2}O{sub 3}-covered low-activation ferritic steel JLF-1 substrate was examined to improve hydrogen permeation barrier performance of the coating. The Cr{sub 2}O{sub 3} layer was obtained before coating by heat treating the substrate at 700 °C under reduced pressures of <5 × 10{sup −3} Pa and 5 Pa. The Cr{sub 2}O{sub 3} layer was significantly stable even with heat treatment at 700 °C in air. This layer prevented further production of Fe{sub 2}O{sub 3}, which has been considered to degrade coating performance. An MOD Er{sub 2}O{sub 3} coating with a smooth surface was successfully obtained on a Cr{sub 2}O{sub 3}-covered JLF-1 substrate by dip coating followed by drying and baking. Preprocessing to obtain a Cr{sub 2}O{sub 3} layer would provide flexibility in the coating process for blanket components and ducts. Moreover, the Cr{sub 2}O{sub 3} layer suppressed hydrogen permeation through the JLF-1 substrate. While further optimization of the coating fabrication process is required, it would be possible to suppress hydrogen permeation significantly by multilayers of Cr{sub 2}O{sub 3} and MOD oxide ceramic. 19. A laboratory study of the oxidation of non toxic Cr(III) to toxic Cr(VI) by OH• free radicals in simulated atmospheric water droplets conditions: Potential environmental impact International Nuclear Information System (INIS) Highlights: • Oxidation of non toxic Cr(III) to toxic Cr(VI) is a major environmental hazard. • oxidation by OH. free radicals generated by water radiolysis. • Oxidation is maximum at pH 4. • A mechanism is proposed. - Abstract: In atmospheric waters, oxidation of Cr(III) to Cr(VI) by OH• free radicals is a major environmental hazard since non-toxic species is transformed into toxic one. It is important to obtain some details concerning this oxidation reaction. In this study we simulated this oxidation by steady state radiolysis using 60Co radioactive source and pulse radiolysis technique using a 2.5 MeV van de Graaff electron accelerator and investigated its kinetics in the pH range 1 to 9. Our findings showed that the reaction was highly pH dependant with a maximum yield at pH 4. The electron transfer proceeds via an inner sphere mechanism with (i) formation of the [OH• –Cr(III)] adduct with an equilibrium constant of 2.34 × 104 mol−1 dm−3 then (ii) followed by an electron transfer from Cr(III) to OH• within the adduct with a rate constant of 2.51 × 104 s−1. The implication of this oxidation to atmospheric chromium contamination is discussed 20. Anaerobic digestion of slaughterhouse by-products Energy Technology Data Exchange (ETDEWEB) Hejnfelt, Anette; Angelidaki, Irini [Department of Environmental Engineering, Technical University of Denmark, DTU, Building 113, DK-2800 Kgs. Lyngby (Denmark) 2009-08-15 Anaerobic digestion of animal by-products was investigated in batch and semi-continuously fed, reactor experiments at 55 C and for some experiments also at 37 C. Separate or mixed by-products from pigs were tested. The methane potential measured by batch assays for meat- and bone flour, fat, blood, hair, meat, ribs, raw waste were: 225, 497, 487, 561, 582, 575, 359, 619 dm{sup 3} kg{sup -1} respectively, corresponding to 50-100% of the calculated theoretical methane potential. Dilution of the by-products had a positive effect on the specific methane yield with the highest dilutions giving the best results. High concentrations of long-chain fatty acids and ammonia in the by-products were found to inhibit the biogas process at concentrations higher than 5 g lipids dm{sup -3} and 7 g N dm{sup -3} respectively. Pretreatment (pasteurization: 70 C, sterilization: 133 C), and alkali hydrolysis (NaOH) had no effect on achieved methane yields. Mesophilic digestion was more stable than thermophilic digestion, and higher methane yield was noticed at high waste concentrations. The lower yield at thermophilic temperature and high waste concentration was due to ammonia inhibition. Co-digestion of 5% pork by-products mixed with pig manure at 37 C showed 40% higher methane production compared to digestion of manure alone. (author) 1. Tillage and Fertilizer Management Effects on Soil-Atmospheric Exchanges of Methane and Nitrous Oxide in a Corn Production System Directory of Open Access Journals (Sweden) Ermson Z. Nyakatawa 2011-01-01 Full Text Available Land application of poultry litter (PL presents an opportunity to improve soil productivity and disposal of poultry waste. We investigated methane (CH4 and nitrous oxide (N2O emissions from agricultural soil receiving PL and ammonium nitrate (AN fertilizers using surface (SA, soil incorporation (SI, and subsurface band (BA application methods in conventional (CT and no-tillage (NT systems on a Decatur silt loam soil in North Alabama. Plots under CT and NT were sinks of CH4 in spring, summer, and fall. In winter, the plots had net emissions of 3.32 and 4.24 g CH4 ha-1 day-1 in CT and NT systems, respectively. Plots which received AN were net emitters of CH4 and N2O, whereas plots which received PL were net sinks of CH4. Plots which received PL using SA or SI methods were net emitters of N2O, whereas under PL using BA application, the plots were net sinks of N2O. Our study indicates that using subsurface band application of PL was the most promising environmentally sustainable poultry waste application method for reducing CH4 and N2O emissions from agricultural soil in NT and CT corn production systems on the Decatur soil in north Alabama. 2. Characterizations of arsenic-doped zinc oxide films produced by atmospheric metal-organic chemical vapor deposition International Nuclear Information System (INIS) p-type ZnO films were prepared by atmospheric metal-organic chemical vapor deposition technique using arsine (AsH3) as the doping source. The electrical and optical properties of arsenic-doped ZnO (ZnO:As) films fabricated at 450–600 °C with various AsH3 flow rates ranging from 8 to 21.34 μmol/min were analyzed and compared. Hall measurements indicate that stable p-type ZnO films with hole concentrations varying from 7.2 × 1015 to 5.8 × 1018 cm−3 could be obtained. Besides, low temperature (17 K) photoluminescence spectra of all ZnO:As films also demonstrate the dominance of the line related to the neutral acceptor-bound exciton. Moreover, the elemental identity and chemical bonding information for ZnO:As films were examined by X-ray photoelectron spectroscopy. Based on the results obtained, the effects of doping conditions on the mechanism responsible for the p-type conduction were studied. Conclusively, a simple technique to fabricate good-quality p-type ZnO films has been recognized in this work. Depositing the film at 550 °C with an AsH3 flow rate of 13.72 μmol/min is appropriate for producing hole concentrations on the order of 1017 cm−3 for it. Ultimately, by increasing the AsH3 flow rate to 21.34 μmol/min for doping and depositing the film at 600 °C, ZnO:As films with a hole concentration over 5 × 1018 cm−3 together with a mobility of 1.93 cm2V−1 s−1 and a resistivity of 0.494 ohm-cm can be achieved. 3. Behaviour of Al2O3 scales on Fe-Al and Fe-Ni-Al alloys with small additions of titanium, zirconium, niobium and vanadium on thermal cycling and creep in oxidizing and carburizing atmospheres International Nuclear Information System (INIS) Aluminium as an alloying element in steels is beneficial for the formation of slow-growing oxide layers at high temperatures. Steels with aluminium as the oxide former are of interest for use in carburizing atmospheres with low O2 partial pressures, e.g. coal gasification or the high temperature nuclear reactor. The behaviour of Al2O3 layers on ferritic and austenitic steels with small additions of titanium, zirconium, niobium and vanadium was studied by measuring radiocarbon penetration in thermal cycling and creep experiments. The oxide layers on the ferritic steels adhered well and were compact with a high carburization resistance. In the creep tests on the austenitic alloys, cracking of the oxide layer and subsequent intergranular oxidation and carburization were observed. (orig.) 4. Anaerobic digestion of slaughterhouse by-products DEFF Research Database (Denmark) Hejnfelt, Anette; Angelidaki, Irini 2009-01-01 hydrolysis (NaOH) had no effect on achieved methane yields. Mesophilic digestion was more stable than thermophilic digestion, and higher methane yield was noticed at high waste concentrations. The lower yield at thermophilic temperature and high waste concentration was due to ammonia inhibition. Co......Anaerobic digestion of animal by-products was investigated in batch and semi-continuously fed, reactor experiments at 55 degrees C and for some experiments also at 37 degrees C. Separate or mixed by-products from pigs were tested. The methane potential measured by batch assays for meat- and bone...... giving the best results. High concentrations of long-chain fatty acids and ammonia in the by-products were found to inhibit the biogas process at concentrations higher than 5 g lipids dm(-3) and 7 gN dm(-3) respectively. Pretreatment (pasteurization: 70 degrees C, sterilization: 133 degrees C, and alkali... 5. Atmospheric oxidation of isoprene and 1,3-butadiene: influence of aerosol acidity and relative humidity on secondary organic aerosol Directory of Open Access Journals (Sweden) M. Lewandowski 2014-11-01 Full Text Available The effects of acidic seed aerosols on the formation of secondary organic aerosol (SOA have been examined in a number of previous studies, several of which have observed strong linear correlations between the aerosol acidity (measured as nmol H+ per m3 air sample volume and the percent change of secondary organic carbon (SOC. The measurements have used several precursor compounds representative of different classes of biogenic hydrocarbons including isoprene, monoterpenes, and sesquiterpenes. To date, isoprene has displayed the most pronounced increase in SOC, although few measurements have been conducted with anthropogenic hydrocarbons. In the present study, we examine several aspects of the effect of aerosol acidity on the secondary organic carbon formation from the photooxidation of 1,3-butadiene, as well as extending the previous analysis of isoprene. The photooxidation products measured in the absence and presence of acidic sulfate aerosols were generated either through photochemical oxidation of SO2 or by nebulizing mixtures of ammonium sulfate and sulfuric acid into a 14.5 m3 smog chamber system. The results showed that, like isoprene and β-caryophyllene, 1,3-butadiene SOC yields linearly correlate with increasing acidic sulfate aerosol. The observed acid sensitivity of 0.11% SOC increase per nmol m−3 increase in H+ was approximately a factor of three less than that measured for isoprene. The results also showed that the aerosol yield decreased with increasing humidity for both isoprene and 1,3-butadiene, although to different degrees. Increasing the absolute humidity from 2 to 12 g m−3 reduced the 1,3-butadiene yield by 45% and the isoprene yield by 85%. 6. Mechanism of the hydroxy radical oxidation of methacryoyl peroxynitrate (MPAN) and its pathway toward secondary organic aerosol formation in the atmosphere Energy Technology Data Exchange (ETDEWEB) Nguyen, Tran B.; Bates, Kelvin H.; Crounse, J. D.; Schwantes, Rebecca H.; Zhang, Xuan; Kjaergaard, Henrik G.; Surratt, Jason D.; Lin, Peng; Laskin, Alexander; Seinfeld, John H.; Wennberg, P. O. 2015-01-01 Methacryoyl peroxynitrate (MPAN), the acylperoxyl nitrate of methacrolein, has been suggested to be an important secondary organic aerosol (SOA) precursor from isoprene oxidation. Yet, the mechanism by which MPAN produces SOA via reaction with the hydroxyl radical (OH) is unclear. We systematically evaluate three proposed mechanisms in controlled chamber experiments and provide the first experimental support for the theoretically-predicted lactone formation pathway from the MPAN + OH reaction, producing hydroxymethyl-methyl-α-lactone (HMML). The decomposition of the MPAN-OH adduct yields HMML + NO3 (~ 75%) and hydroxyacetone + CO + NO3 (~ 25%), out-competing its reaction with atmospheric oxygen. The production of other proposed SOA precursors, e.g., methacrylic acid epoxide (MAE), from MPAN and methacrolein are negligible (< 2 %). Furthermore, we show that the beta-alkenyl moiety of MPAN is critical for lactone formation. Alkyl radicals formed via OH abstraction nstead of addition are thermalized; thus, even if they are structurally identical to the MPAN-OH adduct, they do not decompose to HMML. The SOA formation from HMML, via polyaddition of the lactone to organic compounds, is close to unity under dry conditions. However, the SOA yield is sensitive to particle liquid water and solvated ions. In hydrated sulfate-containing particles, HMML reacts primarily with H2O and aqueous sulfate, producing monomeric 2-methylglyceric acid (2MGA) and the associated organosulfate. 2MGA, a tracer for isoprene SOA, is semivolatile and its volatility increases with decreasing pH in the aerosol water. Conditions that enhance the production of neutral 2MGA will suppress SOA mass from the HMML channel. Considering the liquid water content and pH ranges of ambient particles, MGA may exist largely as a gaseous compound in some parts of the atmosphere. 7. Reaction products and mechanisms for the reaction of n-butyl vinyl ether with the oxidants OH and Cl: Atmospheric implications Science.gov (United States) Colmenar, Inmaculada; Martín, Pilar; Cabañas, Beatriz; Salgado, Sagrario; Tapia, Araceli; Martínez, Ernesto 2015-12-01 A reaction product study for the degradation of butyl vinyl ether (CH3(CH2)3OCHdbnd CH2) by reaction with chlorine atoms (Cl) and hydroxyl radicals (OH) has been carried out using Fourier Transform Infrared absorption spectroscopy (FTIR) and/or Gas Chromatography-Mass Spectrometry with a Time of Flight analyzer (GC-TOFMS). The rate coefficient for the reaction of butyl vinyl ether (BVE) with chlorine atoms has also been evaluated for the first time at room temperature (298 ± 2) K and atmospheric pressure (708 ± 8) Torr. The rate coefficient obtained was (9.9 ± 1.5) × 10-10 cm3 molecule-1 s-1 and this indicates the high reactivity of butyl vinyl ether with Cl atoms. However, this value may be affected by the dark reaction of BVE with Cl2. The results of a qualitative study of the Cl reaction show that the main oxidation products are butyl formate (CH3(CH2)3OC(O)H), butyl chloroacetate (CH3(CH2)3OC(O)CH2Cl and formyl chloride (HCOCl). Individual yields in the ranges ∼16-40% and 30-70% in the absence and presence of NOx, respectively, have been estimated for these products. In the OH reaction, butyl formate and formic acid were identified as the main products, with yields of around 50 and 20%, respectively. Based on the results of this work and a literature survey, the addition of OH radicals and Cl atoms at the terminal C atom of the double bond in CH3(CH2)3OCHdbnd CH2 has been proposed as the first step in the reaction mechanism for both of the studied oxidants. The tropospheric lifetime of butyl vinyl ether is very short and, as a consequence, it will be rapidly degraded and will only be involved in tropospheric chemistry at a local level. The degradation products of these reactions should be considered when evaluating the atmospheric impact. 8. Effects on surface atmospheric photo-oxidants over Greece during the total solar eclipse event of 29 March 2006 Directory of Open Access Journals (Sweden) P. Zanis 2007-08-01 Full Text Available This study investigates the effects of the total solar eclipse of 29 March 2006 on surface air-quality levels over Greece based on observations at a number of sites in conjunction with chemical box modelling and 3-D air-quality modelling. Emphasis is given on surface ozone and other photooxidants at four Greek sites Kastelorizo, Finokalia (Crete, Pallini (Athens and Thessaloniki, which are located at gradually increasing distances from the path of the eclipse totality and are characterized by different air pollution levels. The eclipse offered the opportunity to test our understanding of air pollution build-up and the response of the gas-phase chemistry of photo-oxidants during a photolytical perturbation using both a photochemical box model and a regional air-quality offline model based on the modeling system WRF/CAMx. At the relatively unpolluted sites of Kastelorizo and Finokalia no clear impact of the solar eclipse on surface O3, NO2 and NO concentrations can be deduced from the observations and model simulations as the calculated changes in net ozone production rates between eclipse and non eclipse conditions are rather small compared to the ozone variability and hence the solar eclipse effects on ozone can be easily masked by transport. At the polluted sites of Thessaloniki and Pallini, the solar eclipse effects on O3, NO2 and NO concentrations are clearly revealed from both the measurements and 3-D air-quality modeling with the net effect being a decrease in O3 and NO and an increase in NO2 as NO2 formed from the reaction of O3 with NO while at the same time NO2 is not efficiently photolysed. It is evident from the 3-D air quality modeling over Greece that the maximum effects of the eclipse on O3, NO2 and NO are reflected at the large urban agglomerations of Athens, and Thessaloniki where the maximum of the emissions 9. Effects on surface atmospheric photo-oxidants over Greece during the total solar eclipse event of 29 March 2006 Directory of Open Access Journals (Sweden) P. Zanis 2007-12-01 Full Text Available This study investigates the effects of the total solar eclipse of 29 March 2006 on surface air-quality levels over Greece based on observations at a number of sites in conjunction with chemical box modelling and 3-D air-quality modelling. Emphasis is given on surface ozone and other photooxidants at four Greek sites Kastelorizo, Finokalia (Crete, Pallini (Athens and Thessaloniki, which are located at gradually increasing distances from the path of the eclipse totality and are characterized by different air pollution levels. The eclipse offered the opportunity to test our understanding of air pollution build-up and the response of the gas-phase chemistry of photo-oxidants during a photolytical perturbation using both a photochemical box model and a regional air-quality offline model based on the modeling system WRF/CAMx. At the relatively unpolluted sites of Kastelorizo and Finokalia no clear signal of the solar eclipse on surface O3, NO2 and NO concentrations can be deduced from the observations while there is no correlation of observed O3, NO2 and NO with observed global radiation. The box and regional model simulations for the two relatively unpolluted sites indicate that the calculated changes in net ozone production rates between eclipse and non eclipse conditions are rather small compared to the observed short-term ozone variability. Furthermore the simulated ozone lifetime is in the range of a few days at these sites and hence the solar eclipse effects on ozone can be easily masked by local and regional transport. At the polluted sites of Thessaloniki and Pallini, the solar eclipse effects on O3, NO2 and NO concentrations are revealed from both the measurements and modeling with the net effect being a decrease in O3 and NO and an increase in NO2 as NO2 formed from the reaction of O3 with NO while at the same time NO2 is 10. Oxidation of SO2 by stabilized Criegee intermediate (sCI radicals as a crucial source for atmospheric sulfuric acid concentrations Directory of Open Access Journals (Sweden) M. Boy 2013-04-01 Full Text Available The effect of increased reaction rates of stabilized Criegee intermediates (sCIs with SO2 to produce sulfuric acid is investigated using data from two different locations, SMEAR II, Hyytiälä, Finland, and Hohenpeissenberg, Germany. Results from MALTE, a zero-dimensional model, show that using previous values for the rate coefficients of sCI + SO2, the model underestimates gas phase H2SO4 by up to a factor of two when compared to measurements. Using the rate coefficients recently calculated by Mauldin et al. (2012 increases sulfuric acid by 30–40%. Increasing the rate coefficient for formaldehyde oxide (CH2OO with SO2 according to the values recommended by Welz et al. (2012 increases the H2SO4 yield by 3–6%. Taken together, these increases lead to the conclusion that, depending on their concentrations, the reaction of stabilized Criegee intermediates with SO2 could contribute as much as 33–46% to atmospheric sulfuric acid gas phase concentrations at ground level. Using the SMEAR II data, results from SOSA, a one-dimensional model, show that the contribution from sCI reactions to sulfuric acid production is most important in the canopy, where the concentrations of organic compounds are the highest, but can have significant effects on sulfuric acid concentrations up to 100 m. The recent findings that the reaction of sCI + SO2 is much faster than previously thought together with these results show that the inclusion of this new oxidation mechanism could be crucial in regional as well as global models. 11. Valorization of food processing by-products NARCIS (Netherlands) Chandrasekaran, M.; Nout, M.J.R.; Sarkar, P.K. 2012-01-01 Biotechnology has immense potential for resolving environmental problems and augmenting food production. Particularly, it offers solutions for converting solid wastes into value-added items. In food processing industries that generate voluminous by-products and wastes, valorization can help offset g 12. Atmospheric-Pressure Plasma Jet Processed Pt-Decorated Reduced Graphene Oxides for Counter-Electrodes of Dye-Sensitized Solar Cells Directory of Open Access Journals (Sweden) Ting-Hao Wan 2016-10-01 Full Text Available Ultrafast atmospheric-pressure plasma jet (APPJ processed Pt-decorated reduced graphene oxides (rGOs were used as counter-electrodes in dye-sensitized solar cells (DSSCs. Pastes containing rGO, ethyl cellulose, terpineol, and chloroplatinic acid were screen-printed and sintered by nitrogen dc-pulse APPJs. Pt nanodots were uniformly distributed on the rGO flakes. When using Pt-decorated rGOs as the counter electrodes of DSSCs, the efficiency of the DSSC first increased and then decreased as the APPJ processing time increased. Nitrogen APPJs can effectively remove organic binders and can reduce chloroplatinic acid to Pt, thereby improving the efficiency of DSSCs. However, over-calcination by APPJ can damage the graphenes and degrade the DSSCs. The addition of Pt mainly improves the fill factor, which thereby increases the efficiency of DSSCs. The optimized APPJ processing time was merely 9 s owing to the vigorous interaction among the rGOs, chloroplatinic acid and nitrogen APPJs. 13. Capture of atmospheric CO2 into (BiO)2CO3/graphene or graphene oxide nanocomposites with enhanced photocatalytic performance Science.gov (United States) Zhang, Wendong; Dong, Fan; Zhang, Wei 2015-12-01 Self-assembly of (BiO)2CO3 nanoflakes on graphene (Ge) and graphene oxide (GO) nanosheets, as an effective strategy to improve the photocatalytic performance of two-dimensional (2D) nanostructured materials, were realized by a one-pot efficient capture of atmospheric CO2 at room temperature. The as-synthesized samples were characterized by XRD, SEM, TEM, XPS, UV-vis DRS, Time-resolved ns-level PL and BET-BJH measurement. The photocatalytic activity of the obtained samples was evaluated by the removal of NO at the indoor air level under simulated solar-light irradiation. Compared with pure (BiO)2CO3, (BiO)2CO3/Ge and (BiO)2CO3/GO nanocomposites exhibited enhanced photocatalytic activity due to their large surface areas and pore volume, and efficient charge separation and transfer. The present work could provide a simple method to construct 2D nanocomposites by efficient utilization of CO2 in green synthetic strategy. 14. Net soil-atmosphere fluxes mask patterns in gross production and consumption of nitrous oxide and methane in a managed ecosystem Science.gov (United States) Yang, Wendy H.; Silver, Whendee L. 2016-03-01 Nitrous oxide (N2O) and methane (CH4) are potent greenhouse gases that are both produced and consumed in soil. Production and consumption of these gases are driven by different processes, making it difficult to infer their controls when measuring only net fluxes. We used the trace gas pool dilution technique to simultaneously measure gross fluxes of N2O and CH4 throughout the growing season in a cornfield in northern California, USA. Net N2O fluxes ranged 0-4.5 mg N m-2 d-1 with the N2O yield averaging 0.68 ± 0.02. Gross N2O production was best predicted by net nitrogen (N) mineralization, soil moisture, and soil temperature (R2 = 0.60, n = 39, poxidation exhibited a strong positive relationship with gross CH4 production rates (R2 = 0.67, n = 37, p< 0.001), which reached as high as 5.4 mg C m-2 d-1. Our study is the first to demonstrate the simultaneous in situ measurement of gross N2O and CH4 fluxes, and results highlight that net soil-atmosphere fluxes can mask significant gross production and consumption of these trace gases. 15. Torsion-rotation-vibration effects in the ground and first excited states of methacrolein, a major atmospheric oxidation product of isoprene Energy Technology Data Exchange (ETDEWEB) Zakharenko, O.; Motiyenko, R. A.; Aviles Moreno, J.-R.; Huet, T. R., E-mail: Therese.Huet@univ-lille1.fr [Laboratoire de Physique des Lasers, Atomes et Molécules, UMR8523 CNRS – Université Lille 1, Bâtiment P5, F- 59655 Villeneuve d’Ascq Cedex (France); Jabri, A. [Laboratoire Inter-universitaire des Systèmes Atmosphériques, CNRS - Universités Paris Est Créteil et Paris Diderot, 61 Avenue du Général de Gaulle, 94010 Créteil Cedex (France); Institute for Physical Chemistry, RWTH Aachen University, Aachen (Germany); Kleiner, I. [Laboratoire Inter-universitaire des Systèmes Atmosphériques, CNRS - Universités Paris Est Créteil et Paris Diderot, 61 Avenue du Général de Gaulle, 94010 Créteil Cedex (France) 2016-01-14 Methacrolein is a major oxidation product of isoprene emitted in the troposphere. New spectroscopy information is provided with the aim to allow unambiguous identification of this complex molecule, characterized by a large amplitude motion associated with the methyl top. State-of-the-art millimeter-wave spectroscopy experiments coupled to quantum chemical calculations have been performed. For the most stable s-trans conformer of atmospheric interest, the torsional and rotational structures have been characterized for the ground state, the first excited methyl torsional state (ν{sub 27}), and the first excited skeletal torsional state (ν{sub 26}). The inverse sequence of A and E tunneling sub-states as well as anomalous A-E splittings observed for the rotational lines of v{sub 26} = 1 state clearly indicates a coupling between methyl torsion and skeletal torsion. A comprehensive set of molecular parameters has been obtained. The far infrared spectrum of Durig et al. [Spectrochim. Acta, Part A 42, 89–103 (1986)] was reproduced, and a Fermi interaction between ν{sub 25} and 2ν{sub 27} was evidenced. 16. Peanut by-products fed to cattle. Science.gov (United States) Hill, Gary M 2002-07-01 Peanut by-products supply substantial quantities of feedstuffs to beef cattle grown in the same region where peanuts are produced. Included in the list of products fed to cattle are peanuts and peanut meal, peanut skins, peanut hulls, peanut hay, and silages. Residual peanut hay is by far the most widely used peanut by-product fed to beef cattle, and if it is properly harvested with minimal leaf shatter, it is comparable to good-quality grass hays in nutrient content. Peanut skins are often included in small quantities in cattle and pet foods, supplying both protein and energy. High tannin content of peanut skins can cause severe performance depressions in beef cattle if peanut skins are included at levels higher than 10% of the diet, unless diets contain relatively high CP (above 15% CP), or additional N sources are added such as ammonia or urea. Because dairy cattle diets are often above 16% CP in the total dietary DM, peanut skins may increase milk production when added at levels up to 16% of the dry matter. Peanut hulls are effectively used as a roughage source at levels up to 20% of beef finishing diets, for bedding in dairy cattle loafing sheds (if tested and found to contain low aflatoxin levels), and in a variety of manufactured products. Peanut hulls are economically priced because of their quantity, their inherent high fiber, and low CP content, and they should not be fed as a primary feedstuffs for beef cattle. Peanut by-products are generally priced below other by-products, and they can be incorporated into a variety of supplements and diets for cow herds, growing-finishing cattle, and dairy cattle. PMID:12235662 17. Atmospheric Chemistry and Air Pollution OpenAIRE Gaffney, Jeffrey S.; Marley, Nancy A. 2003-01-01 Atmospheric chemistry is an important discipline for understanding air pollution and its impacts. This mini-review gives a brief history of air pollution and presents an overview of some of the basic photochemistry involved in the production of ozone and other oxidants in the atmosphere. Urban air quality issues are reviewed with a specific focus on ozone and other oxidants, primary and secondary aerosols, alternative fuels, and the potential for chlorine releases to amplify oxidant chemistry... 18. Soil-atmosphere exchange of nitrous oxide, methane and carbon dioxide in a gradient of elevation in the coastal Brazilian Atlantic forest Science.gov (United States) Sousa Neto, E.; Carmo, J. B.; Keller, M.; Martins, S. C.; Alves, L. F.; Vieira, S. A.; Piccolo, M. C.; Camargo, P.; Couto, H. T. Z.; Joly, C. A.; Martinelli, L. A. 2011-03-01 Soils of tropical forests are important to the global budgets of greenhouse gases. The Brazilian Atlantic Forest is the second largest tropical moist forest area of South America, after the vast Amazonian domain. This study aimed to investigate the emissions of nitrous oxide (N2O), carbon dioxide (CO2) and methane (CH4) fluxes along an altitudinal transect and the relation between these fluxes and other climatic, edaphic and biological variables (temperature, fine roots, litterfall, and soil moisture). Annual means of N2O flux were 3.9 (± 0.4), 1.0 (± 0.1), and 0.9 (± 0.2) ng N cm-2 h-1 at altitudes 100, 400, and 1000 m, respectively. On an annual basis, soils consumed CH4 at all altitudes with annual means of -1.0 (± 0.2), -1.8 (± 0.3), and -1.6 (± 0.1) mg m-2 d-1 at 100 m, 400 m and 1000 m, respectively. Estimated mean annual fluxes of CO2 were 3.5, 3.6, and 3.4 μmol m-2 s-1 at altitudes 100, 400 and 1000 m, respectively. N2O fluxes were significantly influenced by soil moisture and temperature. Soil-atmosphere exchange of CH4 responded to changes in soil moisture. Carbon dioxide emissions were strongly influenced by soil temperature. While the temperature gradient observed at our sites is only an imperfect proxy for climatic warming, our results suggest that an increase in air and soil temperatures may result in increases in decomposition rates and gross inorganic nitrogen fluxes that could support consequent increases in soil N2O and CO2 emissions and soil CH4 consumption. 19. Heterogeneous atmospheric chemistry Science.gov (United States) Schryer, D. R. 1982-01-01 The present conference on heterogeneous atmospheric chemistry considers such topics concerning clusters, particles and microparticles as common problems in nucleation and growth, chemical kinetics, and catalysis, chemical reactions with aerosols, electron beam studies of natural and anthropogenic microparticles, and structural studies employing molecular beam techniques, as well as such gas-solid interaction topics as photoassisted reactions, catalyzed photolysis, and heterogeneous catalysis. Also discussed are sulfur dioxide absorption, oxidation, and oxidation inhibition in falling drops, sulfur dioxide/water equilibria, the evidence for heterogeneous catalysis in the atmosphere, the importance of heterogeneous processes to tropospheric chemistry, soot-catalyzed atmospheric reactions, and the concentrations and mechanisms of formation of sulfate in the atmospheric boundary layer. 20. Torrefaction of agricultural by-products: Effects of temperature and time on energy yields Science.gov (United States) Agricultural by-products, such as apple, grape, olive, and tomato pomaces as well as almond and walnut shells, were torrefied at different temperatures and times. Torrefaction of biomass involves heating in an inert atmosphere to remove volatile components for improved grindability and increased ene... 1. Arsenic Removal from Water Using Industrial By-Products Directory of Open Access Journals (Sweden) Branislava M. Lekić 2013-01-01 Full Text Available In this study, removal of arsenic ions using two industrial by-products as adsorbents is represented. Removal of As(III and As(V from water was carried out with industrial by-products: residual from the groundwater treatment process, iron-manganese oxide coated sand (IMOCS, and blast furnace slag from steel production (BFS, both inexpensive and locally available. In addition, the BFS was modified in order to minimise its deteriorating impact on the initial water quality. Kinetic and equilibrium studies were carried out using batch and fixed-bed column adsorption techniques under the conditions that are likely to occur in real water treatment systems. To evaluate the application for real groundwater treatment, the capacities of the selected materials were further compared to those exhibited by commercial sorbents, which were examined under the same experimental conditions. IMOCS was found to be a good and inexpensive sorbent for arsenic, while BFS and modified slag showed the highest affinity towards arsenic. All examined waste materials exhibited better sorption performances for As(V. The maximum sorption capacity in the batch reactor was obtained for blast furnace slag, 4040 μgAs(V/g. 2. Effect of oxidizing and reducing atmospheres on Ba(Ti0.90Zr0.10O3:2V ceramics as characterized by piezoresponse force microscopy Directory of Open Access Journals (Sweden) Francisco Moura 2011-09-01 Full Text Available The effect of annealing atmospheres (At amb, N2 and O2 on the electrical properties of Ba(Ti0.90Zr0.10O3:2V (BZT10:2V ceramics obtained by the mixed oxide method was investigated. X-ray photoelectron spectroscopy (XPS analysis indicates that oxygen vacancies present near Zr and Ti ions reduce ferroelectric properties, especially in samples treated in an ambient atmosphere (At amb. BZT10:2V ceramics sintered in a nitrogen atmosphere showed better dielectric behaviour at room temperature with a dielectric permittivity measured at a frequency of 10 kHz equal to 16800 with dielectric loss of 0.023. Piezoelectric force microscopy (PFM images reveal improvement in the piezoelectric coefficient by sintering the sample under nitrogen atmosphere. Thus, BZT10:2V ceramics sintered under a nitrogen atmosphere can be useful for practical applications which include nonvolatile digital memories, spintronics and data-storage media. 3. Nitrous Oxide Flux Data.gov (United States) U.S. Geological Survey, Department of the Interior — Nitrous Oxide (N20) flux is the net rate of nitrous oxide exchange between an ecosystem and the atmosphere. Data of this variable were generated by the USGS... 4. Formation of C7F15COOH (PFOA) and other perfluorocarboxylic acids during the atmospheric oxidation of 8:2 fluorotelomer alcohol DEFF Research Database (Denmark) Wallington, T. J.; Hurley, M. D.; Xia, J.; 2006-01-01 Calculations using a three-dimensional global atmospheric chemistry model (IMPACT) indicate that n-C8F17CH2CH2-OH (widely used in industrial and consumer products) degrades in the atmosphere to give perfluorooctanoic acid (PFOA) and other perfluorocarboxylic acids (PFCAs). PFOA is persistent, bio... 5. Soil-atmosphere exchange of nitrous oxide, methane and carbon dioxide in a gradient of elevation in the coastal Brazilian Atlantic forest Directory of Open Access Journals (Sweden) E. Sousa Neto 2010-07-01 Full Text Available Soils of tropical forests are important to the global budgets of greenhouse gases. The Brazilian Atlantic Forest is the second largest tropical moist forest area of South America, after the vast Amazonian domain. This study aimed to investigate the emissions of Nitrous Oxide (N2O and Carbon Dioxide (CO2 as well as methane (CH4 emissions and consumptions along an altitudinal transect and the relation between these fluxes and other climatic, edaphic and biological variables (temperature, fine roots, litterfall, and soil moisture. Annual means of N2O flux were 2.6 (±0.5, 0.9 (±0.1, and 0.7 (±0.2 ng N cm−2 h−1 at altitudes 100, 400, and 1000 m, respectively. On an annual basis, soils consumed CH4 at all altitudes with annual means of −1.0 (±0.2, −1.8 (±0.1, and −1.6 (±0.3 mg m−2 d−1 at 100 m, 400 m and 1000 m, respectively. Although not sampled in the hottest and wettest portion of the year because of instrument malfunctions, mean fluxes of CO2 averaged 3.6 (±0.2, 3.5 (±0.3, and 3.1 (±0.3 μmol m−2 s−1 at altitudes 100, 400 and 1000 m, respectively. N2O fluxes were significantly influenced by soil moisture and temperature. Soil-atmosphere exchange of methane responded to changes in soil moisture. Carbon dioxide emissions were strongly influenced by soil temperature. While the temperature gradient observed at our sites is only an imperfect proxy for climate warming, our results suggest that increasing temperatures will result in increased in microbial activity with a consequent increase in soil N2O and CO2 emissions and soil CH4 consumption. 6. Microstructure degradation of cermet anodes for solid oxide fuel cells: Quantification of nickel grain growth in dry and in humid atmospheres Science.gov (United States) Holzer, L.; Iwanschitz, B.; Hocker, Th.; Münch, B.; Prestat, M.; Wiedenmann, D.; Vogt, U.; Holtappels, P.; Sfeir, J.; Mai, A.; Graule, Th. 7. Soil-atmosphere exchange of nitrous oxide, methane and carbon dioxide in a gradient of elevation in the coastal Brazilian Atlantic forest Directory of Open Access Journals (Sweden) E. Sousa Neto 2011-03-01 Full Text Available Soils of tropical forests are important to the global budgets of greenhouse gases. The Brazilian Atlantic Forest is the second largest tropical moist forest area of South America, after the vast Amazonian domain. This study aimed to investigate the emissions of nitrous oxide (N2O, carbon dioxide (CO2 and methane (CH4 fluxes along an altitudinal transect and the relation between these fluxes and other climatic, edaphic and biological variables (temperature, fine roots, litterfall, and soil moisture. Annual means of N2O flux were 3.9 (± 0.4, 1.0 (± 0.1, and 0.9 (± 0.2 ng N cm−2 h−1 at altitudes 100, 400, and 1000 m, respectively. On an annual basis, soils consumed CH4 at all altitudes with annual means of −1.0 (± 0.2, −1.8 (± 0.3, and −1.6 (± 0.1 mg m−2 d−1 at 100 m, 400 m and 1000 m, respectively. Estimated mean annual fluxes of CO2 were 3.5, 3.6, and 3.4 μmol m−2 s−1 at altitudes 100, 400 and 1000 m, respectively. N2O fluxes were significantly influenced by soil moisture and temperature. Soil-atmosphere exchange of CH4 responded to changes in soil moisture. Carbon dioxide emissions were strongly influenced by soil temperature. While the temperature gradient observed at our sites is only an imperfect proxy for climatic warming, our results suggest that an increase in air and soil temperatures may result in increases in decomposition rates and gross inorganic nitrogen fluxes that could support consequent increases in soil N2O and CO2 emissions and soil CH4 consumption. 8. DISINFECTION BY-PRODUCT FORMATION AND CONTROL BY OZONATION AND BIOTREATMENT Science.gov (United States) There is increasing interest in using ozone in water treatment because it is a strong disinfectant and is able to oxidize the precursors of some disinfection by-products (DBPs). However, ozonation itself produces DBPs, like aldehydes and ketones, and increases the concentration ... 9. Oxidation of a chromia-forming nickel base alloy at high temperature in mixed diluted CO/H2O atmospheres OpenAIRE Rouillard, Fabien; Cabet, Céline; Wolski, Krzysztof; Pijolat, Michèle 2009-01-01 Corrosion of a chromia-forming nickel base alloy, Haynes 230_, has been investigated under impure helium containing a few Pa of CO and H2O at 900 °C. It has been found that this alloy reacts simultaneously with CO and H2O. Oxidation by CO has been revealed to occur mainly in the first hours. CO diffuses through the scale via short-circuit pathways and oxidizes Al, Cr and Si at the oxide/metal interface. Kinetics of CO oxidation has been investigated and several rate limiting steps are propose... 10. T91钢高温水蒸气氧化行为%High temperature oxidation of T91 steel in water vapour atmosphere Institute of Scientific and Technical Information of China (English) 王志武; 谢兴 2013-01-01 The oxidation behavior of T91 steel in high temperature water vapor(650℃) is studied experimentally. The oxidation kinetics curves of T91 steel have been mensurated by thermo gravimetric analyzer (TGA) method. The results show that the oxidation kinetics obeys the parabolic law. The oxide scales are examined by X-ray diffraction, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The results show that the formed oxide consists of Fe3 O4 and Fe2 O3; they are flaky, cluster, stripy, granular at different oxidative period. The grain size of oxide is formed with nucleating and growing up. Cr can only be identified from the surface of the oxidation film after lh's oxidation, when the oxidation rate is fast and the subsequent oxidizing reaction is running on the exterior surface of the oxide scale all the time, which is external oxidation. The subsequent oxidizing reaction is running on the exterior surface of the oxide scale all the time, which is external oxidation.%通过T91钢在650℃高温水蒸汽条件下的氧化实验,用静态增重法测定了T91钢的氧化动力学曲线,其氧化动力学遵循类抛物线规律；对氧化膜进行扫描电镜、X射线衍射和能谱分析.结果表明,氧化膜的氧化物类型为Fe2O3和Fe3O4,在不同的氧化时间段分别呈片状、簇状、条状和颗粒状；氧化物晶粒是通过形核和长大形成的；氧化1h时,氧化膜的表面有Cr,其后均未发现Cr,且随后的8h氧化过程中,氧化反应一直在氧化膜的外表层进行,即发生外氧化. 11. Dynamic Response of CoSb2O6 Trirutile-Type Oxides in a CO2 Atmosphere at Low-Temperatures OpenAIRE Alex Guillén-Bonilla; Verónica-María Rodríguez-Betancourtt; Martín Flores-Martínez; Oscar Blanco-Alonso; Juan Reyes-Gómez; Lorenzo Gildo-Ortiz; Héctor Guillén-Bonilla 2014-01-01 Experimental work on the synthesis of the CoSb2O6 oxide and its CO2 sensing properties is presented here. The oxide was synthesized by a microwave-assisted colloidal method in presence of ethylenediamine after calcination at 600 °C. This CoSb2O6 oxide crystallized in a tetragonal structure with cell parameters and Å, and space group P42/mnm. To prove its physical, chemical and sensing properties, the oxide was subjected to a series of te... 12. Research in physical chemistry and chemical education: Part A: Water Mediated Chemistry of Oxidized Atmospheric Compounds Part B: The Development of Surveying Tools to Determine How Effective Laboratory Experiments Contribute to Student Conceptual Understanding Science.gov (United States) Maron, Marta Katarzyna This dissertation is a combination of two research areas, experimental physical chemistry, Chapters I to V, and chemical education, Chapters VI to VII. Chapters I to V describe research on the water-mediated chemistry of oxidized atmospheric molecules and the impact that water has on the spectra of these environmental systems. The role of water in the Earth's atmosphere has been of considerable interest due to its ability to impact chemistry and climate. Oxidized atmospheric molecules in the presence of water have the ability to form hydrogen bonded water complexes. The spectroscopic investigation of nitric acid-water complexes, outlined in Chapter III, was undertaken to characterize intermolecular hydrogen bonds in a water-restricted environment at ambient temperatures. Additionally, this characterization of nitric acid-water complexes allowed for the comparison of calculated overtone OH-stretching vibrational band frequencies, intensities, and anharmonicities of intermolecular hydrogen-bonded water complexes with experimental observations. Oxidized organic molecules, such as aldehydes and ketones, in addition to forming hydrogen-bonded water complexes can undergo a hydration reaction of the carbonyl group and form germinal diols in the presence of water. This chemistry has been studied extensively in bulk aqueous media, however little is known about this process in the gas-phase at low water concentrations. The focus of the studies outlined in Chapters IV and V is motivated by the ability of pyruvic acid and formaldehyde to form germinal diols and water complexes in water-restricted environment. This water-mediated chemistry changes the physical and chemical properties of these organic molecules, therefore, impacting the partitioning between gas and particle phase, as well as the chemistry and photochemistry of oxidized organic molecules in the Earth's atmosphere. The results presented in this dissertation may help resolve the significant discrepancy between 13. Staging atmospheres DEFF Research Database (Denmark) Bille, Mikkel; Bjerregaard, Peter; Sørensen, Tim Flohr 2015-01-01 The article introduces the special issue on staging atmospheres by surveying the philosophical, political and anthropological literature on atmosphere, and explores the relationship between atmosphere, material culture, subjectivity and affect. Atmosphere seems to occupy one of the classic...... localities of tensions between matter and the immaterial, the practical and the ideal, and subject and object. In the colloquial language there can, moreover, often seem to be something authentic or genuine about atmosphere, juxtaposing it to staging, which is implied to be something simulated or artificial....... This introduction seeks to outline how a number of scholars have addressed the relationship between staged atmospheres and experience, and thus highlight both the philosophical, social and political aspects of atmospheres... 14. Atmospheric chemistry of 4 : 2 fluorotelomer alcohol (CF3(CF2)(3)CH2CH2OH): Products and mechanism of Cl atom initiated oxidation DEFF Research Database (Denmark) Hurley, MD; Ball, JC; Wallington, TJ; 2004-01-01 Smog chamber/FTIR techniques were used to study the products and mechanism of the Cl atom initiated oxidation of 4:2 fluorotelomer alcohol (CF3(CF2)(3)CH2CH2OH) in 700 Torr of N-2/O-2 diluent at 296 K. CF3(CF2)(3)CH2CHO is the sole primary oxidation product. CF3(CF2)(3)CHO, CF3(CF2)(3)CH2COOH, an... 15. An identical-location transmission electron microscopy study on the degradation of Pt/C nanoparticles under oxidizing, reducing and neutral atmosphere International Nuclear Information System (INIS) This study shows that the predominant degradation mechanism of Pt/Vulcan XC72 electrocatalysts strongly depends on the nature of the gas atmosphere and of the upper potential limit used in accelerated stress tests (ASTs). The morphological changes of Pt/Vulcan XC72 nanoparticles were studied by identical location transmission electron microscopy (IL-TEM), following accelerated stress tests in different potential ranges and under various gas atmospheres. X-ray photoelectron spectroscopy was used to probe changes in carbon surface chemistry. Whereas minor changes were detected under neutral atmosphere (Ar) and low potential limit conditions (0.05 2). With an increase of the upper potential limit to 1.23 V vs. RHE, the trends observed previously were maintained but 3D Ostwald ripening strongly overlapped with the three other degradation mechanisms, precluding any identification of the dominant mechanism 16. Effect of capacitive deionization on disinfection by-product precursors. Science.gov (United States) Liu, Danyang; Wang, Xiaomao; Xie, Yuefeng F; Tang, Hao L 2016-10-15 Formation of brominated disinfection by-products (DBPs) from bromide and natural organic matter upon chlorination imposes health risks to drinking water users. In this study, capacitive deionization (CDI) was evaluated as a potential process for DBP precursor removal. Synthetic humic acid and bromide containing saline water was used as model water prior to CDI treatment. Batch experiments were conducted at cell voltages of 0.6-, 0.9-, and 1.2V to study the influence of CDI on the ratio of bromide and dissolved organic carbon, bromine substitution factor, and DBP formation potential (FP). Results showed beneficial aspects of CDI on reducing the levels of these parameters. A maximum DBPFP removal from 1510 to 1160μg/L was observed at the cell voltage of 0.6V. For the removed DBPFP, electro-adsorption played a greater role than physical adsorption. However, it is also noted that there could be electrochemical oxidations that led to reduction of humic content and formation of new dichloroacetic acid precursors at high cell voltages. Because of the potential of CDI on reducing health risks from the formation of less brominated DBPs upon subsequent chlorination, it can be considered as a potential technology for DBP control in drinking water treatment. PMID:27285792 17. Disinfection by-product formation during seawater desalination: A review. Science.gov (United States) Kim, Daekyun; Amy, Gary L; Karanfil, Tanju 2015-09-15 Due to increased freshwater demand across the globe, seawater desalination has become the technology of choice in augmenting water supplies in many parts of the world. The use of chemical disinfection is necessary in desalination plants for pre-treatment to control both biofouling as well as the post-disinfection of desalinated water. Although chlorine is the most commonly used disinfectant in desalination plants, its reaction with organic matter produces various disinfection by-products (DBPs) (e.g., trihalomethanes [THMs], haloacetic acids [HAAs], and haloacetonitriles [HANs]), and some DBPs are regulated in many countries due to their potential risks to public health. To reduce the formation of chlorinated DBPs, alternative oxidants (disinfectants) such as chloramines, chlorine dioxide, and ozone can be considered, but they also produce other types of DBPs. In addition, due to high levels of bromide and iodide concentrations in seawater, highly cytotoxic and genotoxic DBP species (i.e., brominated and iodinated DBPs) may form in distribution systems, especially when desalinated water is blended with other source waters having higher levels of organic matter. This article reviews the knowledge accumulated in the last few decades on DBP formation during seawater desalination, and summarizes in detail, the occurrence of DBPs in various thermal and membrane plants involving different desalination processes. The review also identifies the current challenges and future research needs for controlling DBP formation in seawater desalination plants and to reduce the potential toxicity of desalinated water. PMID:26099832 18. Energy, atmospheric chemistry, and global climate Science.gov (United States) Levine, Joel S. 1991-01-01 Global atmospheric changes due to ozone destruction and the greenhouse effect are discussed. The work of the Intergovernmental Panel on Climate Change is reviewed, including its judgements regarding global warming and its recommendations for improving predictive capability. The chemistry of ozone destruction and the global atmospheric budget of nitrous oxide are reviewed, and the global sources of nitrous oxide are described. 19. Aqueous chlorination of mefenamic acid: kinetics, transformation by-products and ecotoxicity assessment. Science.gov (United States) Adira Wan Khalit, Wan Nor; Tay, Kheng Soo 2016-05-18 Mefenamic acid (Mfe) is one of the most frequently detected nonsteroidal anti-inflammatory drugs in the environment. This study investigated the kinetics and the transformation by-products of Mfe during aqueous chlorination. The potential ecotoxicity of the transformation by-products was also evaluated. In the kinetic study, the second-order rate constant (kapp) for the reaction between Mfe and free available chlorine (FAC) was determined at 25 ± 0.1 °C. The result indicated that the degradation of Mfe by FAC is highly pH-dependent. When the pH was increased from 6 to 8, it was found that the kapp for the reaction between Mfe and FAC was decreased from 16.44 to 4.4 M(-1) s(-1). Characterization of the transformation by-products formed during the chlorination of Mfe was carried out using liquid chromatography-quadrupole time-of-flight accurate mass spectrometry. Four major transformation by-products were identified. These transformation by-products were mainly formed through hydroxylation, chlorination and oxidation reactions. Ecotoxicity assessment revealed that transformation by-products, particularly monohydroxylated Mfe which is more toxic than Mfe, can be formed during aqueous chlorination. 20. Efficiencies of metal separation and recovery in ash-melting of municipal solid waste under non-oxidative atmospheres with different reducing abilities. Science.gov (United States) 2016-01-15 Ash-melting of municipal solid waste produces molten metal that contains Fe and Cu, and melting furnace fly ash (MFA) that contains Pb and Zn. To recover the metal from the fly ash, Pb and Zn are extracted from the ash by water or enriched in the ash by washing out salts; this separation depends on their leachability. In this study, we investigated the effects of the reducing ability of the atmosphere on the efficiencies of metal separation during melting and metal recovery in water treatment. Different feedstocks (incineration residues) were melted under N2 or CO + N2 atmospheres. In some of the feedstock materials, volatilization of metallic Cu into MFA was promoted under the atmosphere with greater reducing ability (CO + N2). This increased volatilization inhibited the metal separation in the ash-melting process. Moreover, the higher reducing ability inhibited the formation of water-soluble lead chlorides and decreased the efficiency of metal recovery from the MFA because of the water leaching of the lead compounds. The reducing ability of the atmosphere is difficult to control uniformly in actual ash-melting plants, and we investigated appropriate melting conditions under which the effect of the reducing ability was minimized to promote metal separation and recovery. This minimization was achieved by melting incineration fly ash without additives with Cl gas treatment at 1400 °C. 1. Exoplanet Atmospheres CERN Document Server Seager, S 2010-01-01 At the dawn of the first discovery of exoplanets orbiting sun-like stars in the mid-1990s, few believed that observations of exoplanet atmospheres would ever be possible. After the 2002 Hubble Space Telescope detection of a transiting exoplanet atmosphere, many skeptics discounted it as a one-object, one-method success. Nevertheless, the field is now firmly established, with over two dozen exoplanet atmospheres observed today. Hot Jupiters are the type of exoplanet currently most amenable to study. Highlights include: detection of molecular spectral features; observation of day-night temperature gradients; and constraints on vertical atmospheric structure. Atmospheres of giant planets far from their host stars are also being studied with direct imaging. The ultimate exoplanet goal is to answer the enigmatic and ancient question, "Are we alone?" via detection of atmospheric biosignatures. Two exciting prospects are the immediate focus on transiting super Earths orbiting in the habitable zone of M-dwarfs, and u... 2. Atmospheric Neutrinos OpenAIRE Takaaki Kajita 2012-01-01 Atmospheric neutrinos are produced as decay products in hadronic showers resulting from collisions of cosmic rays with nuclei in the atmosphere. Electron-neutrinos and muon-neutrinos are produced mainly by the decay chain of charged pions to muons to electrons. Atmospheric neutrino experiments observed zenith angle and energy-dependent deficit of muon-neutrino events. It was found that neutrino oscillations between muon-neutrinos and tau-neutrinos explain these data well. This paper discusses... 3. Articulating Atmospheres DEFF Research Database (Denmark) Kinch, Sofie 2011-01-01 This paper presents an architectural approach to designing computational interfaces by articulating the notion of atmosphere in the field of interaction design. It draws upon the concept of kinesthetic interaction and a philosophical notion on atmosphere emphasizing the importance of bodily...... experience in space, presented as middle ground experience. In the field of HCI, middle ground experiences complete the unarticulated spectrum between designing for foreground of attention or background awareness. When “Articulating Atmospheres through Middle Ground Experiences in Interaction Design... 4. How and why electrostatic charge of combustible nanoparticles can radically change the mechanism and rate of their oxidation in humid atmosphere CERN Document Server Meshcheryakov, Oleg 2010-01-01 Electrostatically charged aerosol nanoparticles strongly attract surrounding polar gas molecules due to a charge-dipole interaction. In humid air, the substantial electrostatic attraction and acceleration of surrounding water vapour molecules towards charged combustible nanoparticles cause intense electrostatic hydration and preferential oxidation of these nanoparticles by accelerated water vapor molecules rather than non-polar oxygen molecules. In particular, electrostatic acceleration, acquired by surrounding water vapour molecules at a distance of their mean free path from the minimally charged iron metal nanoparticle can increase an oxidative activity of these polar molecules with respect to the nanoparticle by a factor of one million. Intense electrostatic hydration of charged metal nanoparticles converts the nanoparticle's oxide based shells into the hydroxide based electrolyte shells, transforming these nanoparticles into metal/air core-shell nanobatteries, periodically short-circuited by intra-particl... 5. Pluto's atmosphere International Nuclear Information System (INIS) Airborne CCD photometer observations of Pluto's June 9, 1988 stellar occultation have yielded an occultation lightcurve, probing two regions on the sunrise limb 2000 km apart, which reveals an upper atmosphere overlying an extinction layer with an abrupt upper boundary. The extinction layer may surround the entire planet. Attention is given to a model atmosphere whose occultation lightcurve closely duplicates observations; fits of the model to the immersion and emersion lightcurves exhibit no significant derived atmosphere-structure differences. Assuming a pure methane atmosphere, surface pressures of the order of 3 microbars are consistent with the occultation data. 43 references 6. Atmospheric electricity CERN Document Server Chalmers, J Alan 1957-01-01 Atmospheric Electricity brings together numerous studies on various aspects of atmospheric electricity. This book is composed of 13 chapters that cover the main problems in the field, including the maintenance of the negative charge on the earth and the origin of the charges in thunderstorms. After a brief overview of the historical developments of atmospheric electricity, this book goes on dealing with the general principles, results, methods, and the MKS system of the field. The succeeding chapters are devoted to some aspects of electricity in the atmosphere, such as the occurrence and d 7. High-temperature oxidation of iron, Fe-0.5 wt. % Al and Fe-1 wt% Al alloys in CO2 at atmospheric pressure International Nuclear Information System (INIS) The oxidation of several grades of iron (on being a zone-melting grade) in the poly- and monocrystalline forms between 570 and 11500C proceeds along a linear, then a transitory and a parabolic law in correspondence with the growth of wustite possibly covered with magnetite, whereas in the 400-5700C range where the parabolic law is rapidly establishing, the scale is entirely formed of magnetite. The oxidation of the two Fe-A1 alloys follows similarly a quasi linear law after a very short linear period. Their weight gains differ only at 10% at most while remaining close to that of iron (except above 5700C where they are much lower). The activation energies correspponding to the parabolic process -and in some cases to the linear one- have been determined for each material. They are in the range 11 to 43 Kcal.mole-1, such values being rather low. The characteristics of the oxide layers: mode and facies of nucleation and crystal growth -particularly of the ridges at grain boundaries- the evolution of interfaces, precipitation of magnetite within wustite, etc... have been thoroughly investigated. Finally mechanisms concerning the linear, transitory and parabolic oxidation processes have been proposed after a careful discussion of the results 8. Dynamic Response of CoSb2O6 Trirutile-Type Oxides in a CO2 Atmosphere at Low-Temperatures Directory of Open Access Journals (Sweden) Alex Guillén-Bonilla 2014-08-01 Full Text Available Experimental work on the synthesis of the CoSb2O6 oxide and its CO2 sensing properties is presented here. The oxide was synthesized by a microwave-assisted colloidal method in presence of ethylenediamine after calcination at 600 °C. This CoSb2O6 oxide crystallized in a tetragonal structure with cell parameters and Å, and space group P42/mnm. To prove its physical, chemical and sensing properties, the oxide was subjected to a series of tests: Raman spectroscopy, Scanning Electron Microscopy (SEM and impedance (Z measurements. Microstructures, like columns, bars and hollow hemispheres, were observed. For the CO2 sensing test, a thick film of CoSb2O6 was used, measuring the impedance variations on the presence of air/CO2 flows (0.100 sccm/0.100 sccm using AC (alternating current signals in the frequency-range 0.1–100 kHz and low relative temperatures (250 and 300 °C. The CO2 sensing results were quite good. 9. Fluctuations in late Neoproterozoic atmospheric oxidation — Cr isotope chemostratigraphy and iron speciation of the late Ediacaran lower Arroyo del Soldado Group (Uruguay) DEFF Research Database (Denmark) Frei, Robert; Gaucher, Claudio; Stolper, Daniel; 2013-01-01 .0‰) in iron-rich cherts and banded iron formation horizons within the Arroyo del Soldado Group (Ediacaran; Uruguay) that can be explained by rapid, effective oxidation of Fe(II)-rich surface waters. These fluctuations are correlated with variations in ratios of highly reactive iron (FeHR) to total iron (Fetot... 10. Kinetic study of the OH, NO3 radicals and Cl atom initiated atmospheric photo-oxidation of iso-propenyl methyl ether Science.gov (United States) Taccone, Raúl Alberto; Moreno, Alberto; Colmenar, Inmaculada; Salgado, Sagrario; Martín, María Pilar; Cabañas, Beatriz 2016-02-01 Rate coefficients at room temperature and atmospheric pressure for the reaction of isopropenyl methyl ether (i-PME) (CH2dbnd C(CH3)OCH3), with OH and NO3 radicals and with Cl atoms have been determined in a 50 L Pyrex glass reaction chamber in conjunction with Fourier Transform Infrared absorption spectroscopy (FTIR) as a detection technique. The chamber is equipped with a White-type multiple-reflection mirror system with a total optical path length of ≈200 m. Additional experiments were carried out using evacuable Teflon-coated bags (volume 150 L) and a gas chromatography/mass spectrometry-time of flight (GC-TOF MS) detection system. This is the first kinetic study carried out to date for these reactions. The rate coefficients k (in units of cm3 molecule-1 s-1) obtained are: (1.14 ± 0.10) × 10-10 for the OH reaction, (2.41 ± 0.50) × 10-11, for the NO3 reaction and (7.03 ± 0.67) × 10-10 for the Cl reaction. A mechanism is proposed from the observed reaction products. The atmospheric lifetimes of the studied ether is estimated considering the rate coefficients of the reactions with OH and NO3 radicals and Cl atom. Calculated atmospheric lifetimes reveal that the dominant loss process for i-PME is clearly the night-time reaction with the NO3 radical. The radiative efficiency (RE) is obtained from the infrared spectra of the ether and the global warming potential (GWP) is then estimated. Atmospheric implications of the ether emission are discussed. 11. Atmospheric CO2, d(O2/N2), APO and oxidative ratios from aircraft flask samples over Fyodorovskoye, Western Russia NARCIS (Netherlands) Laan, van der S.; Laan-Luijkx, van der I.T.; Rödenbeck, C.; Varlagin, A.; Shironya, I.; Neubert, R.E.M. 2014-01-01 We present atmospheric CO2 and d(O2/N2) from flask samples taken on board aircraft over Fyodorovskoye (56°27'N, 32°55'E) at heights of 3000 m and 100 m between 1998 and 2008. The long-term trends for CO2 and d(O2/N2) are similar for both sampling heights, and also similar to observations from marine 12. Atmospheric CO2, delta(O-2/N-2), APO and oxidative ratios from aircraft flask samples over Fyodorovskoye, Western Russia NARCIS (Netherlands) van der Laan, Sander; van der Laan - Luijkx, Ingrid; Roedenbeck, C.; Varlagin, A.; Shironya, I.; Neubert, R. E. M.; Ramonet, M.; Meijer, H. A. J. 2014-01-01 We present atmospheric CO2 and delta(O-2/N-2) from flask samples taken on board aircraft over Fyodorovskoye (56 degrees 27'N, 32 degrees 55'E) at heights of 3000 m and 100 m between 1998 and 2008. The long-term trends for CO2 and delta(O-2/N-2) are similar for both sampling heights, and also similar 13. Atmospheric Chemistry of cis-CF3CH=CHF: Kinetics of reactions with OH radicals and O3 and products of OH radical initiated oxidation DEFF Research Database (Denmark) Nilsson, Elna Johanna Kristina; Nielsen, Ole John; Johnson, Matthew Stanley; 2009-01-01 which are indistinguishable from 100%. The atmospheric lifetime of cis-CF3CH@CHF is determined by its reaction with OH and is approximately 10 days. cis-CF3CH@CHF has an integrated IR absorption cross section (600–2000 cm1) of (1.71 ± 0.09) 1016 cm molecule1 and a global warming potential...... of approximately 3 (100 year time horizon). Quoted uncertainties reflect two standard deviations from least squares regression analyses.... 14. Maximizing Utilization of Energy from Crop By-products OpenAIRE Budi Haryanto 2014-01-01 The availability of crop by-products is huge during harvesting times as related to the vast agricultural land area; however, their utilization is still limited due to lack of knowledge and handling problem. Seasonal effect is obvious especially during wet season when high rainfall hinders proper management of crop by-products. Crop by-products are energy rich feedstuffs in the form of chemical substance such as cellulose and hemicellulose. The utilization of cellulose and hemicellulose as sou... 15. Chemical stabilization of cadmium in acidic soil using alkaline agronomic and industrial by-products. Science.gov (United States) Chang, Yao-Tsung; Hsi, Hsing-Cheng; Hseu, Zeng-Yei; Jheng, Shao-Liang 2013-01-01 In situ immobilization of heavy metals using reactive or stabilizing materials is a promising solution for soil remediation. Therefore, four agronomic and industrial by-products [wood biochar (WB), crushed oyster shell (OS), blast furnace slag (BFS), and fluidized-bed crystallized calcium (FBCC)] and CaCO3 were added to acidic soil (Cd = 8.71 mg kg(-1)) at the rates of 1%, 2%, and 4% and incubated for 90 d. Chinese cabbage (Brassica chinensis L.) was then planted in the soil to test the Cd uptake. The elevation in soil pH caused by adding the by-products produced a negative charge on the soil surface, which enhanced Cd adsorption. Consequently, the diethylenetriamine pentaacetic acid (DTPA)-extractable Cd content decreased significantly (P < 0.05) in the incubated soil. These results from the sequential extraction procedure indicated that Cd converted from the exchangeable fraction to the carbonate or Fe-Mn oxide fraction. The long-term effectiveness of Cd immobilization caused by applying the 4 by-products was much greater than that caused by applying CaCO3. Plant shoot biomass clearly increased because of the by-product soil amendment. Cd concentration in the shoots was < 10.0 mg kg(-1) following by-product application, as compared to 24 mg kg(-1) for plants growing in unamended soil. PMID:23947715 16. Sterilization of E.coli bacterium with an atmospheric pressure surface barrier discharge Institute of Scientific and Technical Information of China (English) Xu Lei; Zhang Rui; Liu Peng; Ding Li-Li; Zhan Ru-Juan 2004-01-01 The atmospheric pressure surface barrier discharge (APSBD) in air has been used in killing Escherichia coli (E.coli). There is almost no bacterial colony in the sample after treatment by discharge plasma for 2 min. A diagnostic technique based on mass spectrum has been applied to the discharge gas and the mechanism of killing is discussed.Ozone and monatomic oxide are considered to be the major antimicrobial active species. There is almost no harmful by-product. The experiment proves that APSBD plasma is a very simple, effective and innocuous tool for sterilization. 17. Conductivity of perovskites La0.9Sr0.1Sc1- x Fe x O3-α ( x = 0.003-0.47) in oxidizing and reducing atmospheres Science.gov (United States) Stroeva, A. Yu.; Gorelov, V. P.; Kuz'min, A. V. 2016-08-01 The conductivity of single-phase ceramic materials based on proton-conducting perovskite La0.9Sr0.1ScO3-α containing from 0.3 to 47 at % Fe in the scandium sublattice has been studied. Synthesis has been performed by burning with ethylene glycol. Measurements have been carried out by the four-probe (500-900°C) and impedance (100-500°C) methods in oxidizing and reducing atmospheres, as well as at different pressures {p_{{O_2}}} (2.1 × 104-10‒15 Pa) and {p_{{H_2}O}} (0.04-2.5 kPa). Substitution of scandium with iron significantly decreases the proton conductivity. 18. Exoplanetary Atmospheres CERN Document Server Madhusudhan, Nikku; Fortney, Jonathan; Barman, Travis 2014-01-01 The study of exoplanetary atmospheres is one of the most exciting and dynamic frontiers in astronomy. Over the past two decades ongoing surveys have revealed an astonishing diversity in the planetary masses, radii, temperatures, orbital parameters, and host stellar properties of exoplanetary systems. We are now moving into an era where we can begin to address fundamental questions concerning the diversity of exoplanetary compositions, atmospheric and interior processes, and formation histories, just as have been pursued for solar system planets over the past century. Exoplanetary atmospheres provide a direct means to address these questions via their observable spectral signatures. In the last decade, and particularly in the last five years, tremendous progress has been made in detecting atmospheric signatures of exoplanets through photometric and spectroscopic methods using a variety of space-borne and/or ground-based observational facilities. These observations are beginning to provide important constraints... 19. Atmospheric composition Science.gov (United States) Daniels, G. E. 1973-01-01 The earth's atmosphere is made up of a number of gases in different relative amounts. Near sea level and up to about 90 km, the amount of these atmospheric gases in clean, relatively dry air is practically constant. Four of these gases, nitrogen, oxygen, argon, and carbon dioxide, make up 99.99 percent by volume of the atmosphere. Two gases, ozone and water vapor, change in relative amounts, but the total amount of these two is very small compared to the amount of the other gases. The atmospheric composition shown in a table can be considered valid up to 90 km geometric altitude. Above 90 km, mainly because of molecular dissociation and diffusive separation, the composition changes. 20. Interpreting the Ultraviolet Aerosol Index Observed with the OMI Satellite Instrument to Understand Absorption by Organic Carbon Aerosols and Implications for Atmospheric Oxidation Science.gov (United States) Hammer, M. S.; Martin, R.; van Donkelaar, A.; Buchard, V.; Torres, O.; Ridley, D. A.; Spurr, R. J. D. 2015-12-01 Absorption of solar radiation by aerosols plays a major role in radiative forcing and atmospheric photochemistry. Many atmospheric chemistry models tend to overestimate tropospheric OH concentrations compared to observations. Accurately representing aerosol absorption in the UV could help rectify the discrepancies between simulated and observed OH concentrations. We develop a simulation of the Ultraviolet Aerosol Index (UVAI), using the 3-D chemical transport model GEOS-Chem coupled with the Vector Linearized Discrete Ordinate Radiative Transfer model (VLIDORT). The simulation is applied to interpret UVAI observations from the Ozone Monitoring Instrument (OMI). Simulated and observed values are highly consistent in regions where mineral dust dominates the UVAI, but a large negative bias (-0.4 to -1.0) exists between simulated and observed values in biomass burning regions. We implement optical properties for absorbing organic aerosol, known as brown carbon (BrC), into GEOS-Chem and evaluate the simulation with observed UVAI values over biomass burning regions. The spectral dependence of absorption after adding BrC to the model is broadly consistent with reported observations for biomass burning aerosol, with Absorbing Angstrom Exponent (AAE) values ranging from 2.7 in the UV to 1.3 across the UV-Near IR spectrum. The addition of absorbing BrC decreases the mean bias between simulated and OMI UVAI values from -0.60 to -0.08 over North Africa in January, from -0.40 to -0.003 over South Asia in April, from -1.0 to -0.24 over southern Africa in July, and from -0.50 to +0.34 over South America in September. We assess the effect of the additional UV absorption by BrC on atmospheric photochemistry by examining ozone photolysis frequencies (J(O(1D))) and tropospheric OH concentrations in GEOS-Chem. The inclusion of BrC decreases J(O(1D)) and OH by up to 35% over biomass burning regions, and reduces the global bias in OH. 1. Nióbia sintética modificada como catalisador na oxidação de corante orgânico: utilização de H2O2 e O2 atmosférico como oxidantes Modified synthetic niobia as catalyst in the oxidation of organic dye: utilization of H2O2 and atmospheric O2 as oxidants Directory of Open Access Journals (Sweden) Kele T. G. Carvalho 2009-01-01 Full Text Available In this work synthetic niobia was used to promote the oxidation of methylene blue dye in aqueous medium. The niobia was characterized by N2 adsorption/desorption, XRD and TG measurements. The presence of reactive species on the niobia surface strongly increased the oxidation rate of the methylene blue dye. The reaction mechanism was studied by ESI-MS suggesting that the oxidation of the organic dye involve oxidizing species generated mainly after previous treatment with H2O2. It can be observed that the catalyst is a good material in the activation of gas (atmospheric oxygen or liquid (hydrogen peroxide oxidant agent with a total discoloration of the dye solution after only 1 h of reaction. 2. Nitrous oxide in fresh water systems: An estimate for the yield of atmospheric N2O associated with disposal of human waste Science.gov (United States) Kaplan, W. A.; Elkins, J. W.; Kolb, C. E.; Mcelroy, M. B.; Wofsy, S. C.; Duran, A. P. 1977-01-01 The N2O content of waters in the Potomac and Merrimack Rivers was measured on a number of occasions over the period April to July 1977. The concentrations of dissolved N2O exceeded those which would apply in equilibrium with air by factors ranging from about 46 in the Potomac to 1.2 in the Merrimack. Highest concentrations of dissolved N2O were associated with sewage discharges from the vicinity of Washington, D. C., and analysis indicates a relatively high yield, 1.3 to 11%, for prompt conversion of waste nitrogen to N2O. Measurements of dissolved N2O in fresh water ponds near Boston demonstrated that aquatic systems provide both strong sources and sinks for atmospheric N2O. 3. Atmospheric oxidation of 1,3-butadiene: characterization of gas and aerosol reaction products and implications for PM2.5 Science.gov (United States) Jaoui, M.; Lewandowski, M.; Docherty, K.; Offenberg, J. H.; Kleindienst, T. E. 2014-12-01 examined. The contribution of SOA products from 13BD oxidation to ambient PM2.5 was investigated by analyzing a series of ambient PM2.5 samples collected in several locations around the United States. In addition to the occurrence of several organic compounds in field and laboratory samples, glyceric acid, d-threitol, erythritol, erythrose, and threonic acid were found to originate only from the oxidation of 13BD based on our previous experiments involving chamber oxidation of a series of hydrocarbons. Initial attempts have been made to quantify the concentrations of these compounds. The average concentrations of these compounds in ambient PM2.5 samples from the California Research at the Nexus of Air Quality and Climate Change (CalNex) study ranged from 0 to approximately 14.1 ng m-3. The occurrence of several other compounds in both laboratory and field samples suggests that SOA originating from 13BD oxidation could contribute to the ambient aerosol mainly in areas with high 13BD emission rates. 4. By-products of palm oil extraction and refining OpenAIRE Tan Yew-Ai 2006-01-01 This paper outlines the utilisation of by-products resulting from the extraction and refining of palm oil. It summarises research by the Malaysian Palm Oil Board (MPOB) directed at producing zero waste from the palm oil industry. MPOB regards by-products of the palm oil industry not as waste but resources. It will be evident that by-products from the palm oil industry can be and have been used extensively and that the research carried out is relevant to both the milling and refining sectors. 5. By-products of palm oil extraction and refining Directory of Open Access Journals (Sweden) Tan Yew-Ai 2006-01-01 Full Text Available This paper outlines the utilisation of by-products resulting from the extraction and refining of palm oil. It summarises research by the Malaysian Palm Oil Board (MPOB directed at producing zero waste from the palm oil industry. MPOB regards by-products of the palm oil industry not as waste but resources. It will be evident that by-products from the palm oil industry can be and have been used extensively and that the research carried out is relevant to both the milling and refining sectors. 6. Bioactive peptides generated from meat industry by-products OpenAIRE Mora, Leticia; Reig, Milagro; Toldrá, Fidel 2014-01-01 There is a large generation of meat by-products, not only from slaughtering but also in the meat industry from trimming and deboning during further processing. This results in extraordinary volumes of by-products that are primarily used as feeds with low returns or, more recently, to biodiesel generation. The aim of this work was to review the state of the art to generate bioactive peptides from meat industry by-products giving them an added value. Hydrolysis with commercial proteases constit... 7. A Review of Antioxidant Peptides Derived from Meat Muscle and By-Products Science.gov (United States) Liu, Rui; Xing, Lujuan; Fu, Qingquan; Zhou, Guang-hong; Zhang, Wan-gang 2016-01-01 Antioxidant peptides are gradually being accepted as food ingredients, supplemented in functional food and nutraceuticals, to positively regulate oxidative stress in the human body against lipid and protein oxidation. Meat muscle and meat by-products are rich sources of proteins and can be regarded as good materials for the production of bioactive peptides by use of enzymatic hydrolysis or direct solvent extraction. In recent years, there has been a growing number of studies conducted to characterize antioxidant peptides or hydrolysates derived from meat muscle and by-products as well as processed meat products, including dry-cured hams. Antioxidant peptides obtained from animal sources could exert not only nutritional value but also bioavailability to benefit human health. This paper reviews the antioxidant peptides or protein hydrolysates identified in muscle protein and by-products. We focus on the procedure for the generation of peptides with antioxidant capacity including the acquisition of crude peptides, the assessment of antioxidant activity, and the purification and identification of the active fraction. It remains critical to perform validation experiments with a cell model, animal model or clinical trial to eliminate safety concerns before final application in the food system. In addition, some of the common characteristics on structure-activity relationship are also reviewed based on the identified antioxidant peptides. PMID:27657142 8. A Review of Antioxidant Peptides Derived from Meat Muscle and By-Products Directory of Open Access Journals (Sweden) Rui Liu 2016-09-01 Full Text Available Antioxidant peptides are gradually being accepted as food ingredients, supplemented in functional food and nutraceuticals, to positively regulate oxidative stress in the human body against lipid and protein oxidation. Meat muscle and meat by-products are rich sources of proteins and can be regarded as good materials for the production of bioactive peptides by use of enzymatic hydrolysis or direct solvent extraction. In recent years, there has been a growing number of studies conducted to characterize antioxidant peptides or hydrolysates derived from meat muscle and by-products as well as processed meat products, including dry-cured hams. Antioxidant peptides obtained from animal sources could exert not only nutritional value but also bioavailability to benefit human health. This paper reviews the antioxidant peptides or protein hydrolysates identified in muscle protein and by-products. We focus on the procedure for the generation of peptides with antioxidant capacity including the acquisition of crude peptides, the assessment of antioxidant activity, and the purification and identification of the active fraction. It remains critical to perform validation experiments with a cell model, animal model or clinical trial to eliminate safety concerns before final application in the food system. In addition, some of the common characteristics on structure-activity relationship are also reviewed based on the identified antioxidant peptides. 9. A Review of Antioxidant Peptides Derived from Meat Muscle and By-Products. Science.gov (United States) Liu, Rui; Xing, Lujuan; Fu, Qingquan; Zhou, Guang-Hong; Zhang, Wan-Gang 2016-01-01 Antioxidant peptides are gradually being accepted as food ingredients, supplemented in functional food and nutraceuticals, to positively regulate oxidative stress in the human body against lipid and protein oxidation. Meat muscle and meat by-products are rich sources of proteins and can be regarded as good materials for the production of bioactive peptides by use of enzymatic hydrolysis or direct solvent extraction. In recent years, there has been a growing number of studies conducted to characterize antioxidant peptides or hydrolysates derived from meat muscle and by-products as well as processed meat products, including dry-cured hams. Antioxidant peptides obtained from animal sources could exert not only nutritional value but also bioavailability to benefit human health. This paper reviews the antioxidant peptides or protein hydrolysates identified in muscle protein and by-products. We focus on the procedure for the generation of peptides with antioxidant capacity including the acquisition of crude peptides, the assessment of antioxidant activity, and the purification and identification of the active fraction. It remains critical to perform validation experiments with a cell model, animal model or clinical trial to eliminate safety concerns before final application in the food system. In addition, some of the common characteristics on structure-activity relationship are also reviewed based on the identified antioxidant peptides. PMID:27657142 10. Atmospheric thermodynamics CERN Document Server Iribarne, J V 1973-01-01 The thermodynamics of the atmosphere is the subject of several chapters in most textbooks on dynamic meteorology, but there is no work in English to give the subject a specific and more extensive treatment. In writing the present textbook, we have tried to fill this rather remarkable gap in the literature related to atmospheric sciences. Our aim has been to provide students of meteorology with a book that can playa role similar to the textbooks on chemical thermodynamics for the chemists. This implies a previous knowledge of general thermodynamics, such as students acquire in general physics courses; therefore, although the basic principles are reviewed (in the first four chapters), they are only briefly discussed, and emphasis is laid on those topics that will be useful in later chapters, through their application to atmospheric problems. No attempt has been made to introduce the thermodynamics of irreversible processes; on the other hand, consideration of heterogeneous and open homogeneous systems permits a... 11. Theoretical investigation on the atmospheric fate of CF3C(O)OCH 2O radical: alpha-ester rearrangement vs oxidation at 298 K. Science.gov (United States) Mishra, Bhupesh Kumar 2014-09-01 A theoretical study on the mechanism of the thermal decomposition of CF(3)C(O)OCH(2)O radical is presented for the first time. Geometry optimization and frequency calculations were performed at the MPWB1K/6-31 + G(d, p) level of theory and energetic information further refined by calculating the energy of the species using G2(MP2) theory. Three plausible decomposition pathways including α-ester rearrangement, reaction with O(2) and thermal decomposition (C-O bond scission) were considered in detail. Our results reveal that reaction with O(2) is the dominant path for the decomposition of CF(3)C(O)OCH(2)O radical in the atmosphere, involving the lowest energy barrier, which is in accord with experimental findings. Our theoretical results also suggest that α-ester rearrangement leading to the formation of trifluoroacetic acid TFA makes a negligible contribution to decomposition of the title alkoxy radical. The thermal rate constants for the above decomposition pathways were evaluated using canonical transition state theory (CTST) at 298 K. PMID:25208556 12. Wastes and by-products - alternatives for agricultural use International Nuclear Information System (INIS) Top address a growing national problem with generation of wastes and by-products, TVA has been involved for several years with developing and commercializing environmentally responsible practices for eliminating, minimizing, or utilizing various wastes/by-products. In many cases, reducing waste generation is impractical, but the wastes/by-products can be converted into other environmentally sound products. In some instances, conversion of safe, value-added agricultural products in the best or only practical alternative. TVA is currently involved with a diversity of projects converting wastes/by-products into safe, economical, and agriculturally beneficial products. Environmental improvement projects have involved poultry litter, cellulosic wastes, used battery acid, ammonium sulfate fines, lead smelting effluents, deep-welled sulfuric acid/ammonium bisulfate solutions, wood ash, waste magnesium ammonium sulfate slurry from recording tape production, and ammunition plant waste sodium nitrate/ammonium nitrate streams 13. Wastes and by-products - alternatives for agricultural use Energy Technology Data Exchange (ETDEWEB) Boles, J.L.; Craft, D.J.; Parker, B.R. 1994-10-01 Top address a growing national problem with generation of wastes and by-products, TVA has been involved for several years with developing and commercializing environmentally responsible practices for eliminating, minimizing, or utilizing various wastes/by-products. In many cases, reducing waste generation is impractical, but the wastes/by-products can be converted into other environmentally sound products. In some instances, conversion of safe, value-added agricultural products in the best or only practical alternative. TVA is currently involved with a diversity of projects converting wastes/by-products into safe, economical, and agriculturally beneficial products. Environmental improvement projects have involved poultry litter, cellulosic wastes, used battery acid, ammonium sulfate fines, lead smelting effluents, deep-welled sulfuric acid/ammonium bisulfate solutions, wood ash, waste magnesium ammonium sulfate slurry from recording tape production, and ammunition plant waste sodium nitrate/ammonium nitrate streams. 14. Formation and Occurrence of Disinfection By-Products Science.gov (United States) Disinfection by-products (DBPs) are formed when disinfectants such as chlorine, ozone, chlorine dioxide, or chloramines react with naturally occurring organic matter, anthropogenic contaminants, bromide, and iodide during the production of drinking water. There is concern about D... 15. SOA formation from the atmospheric oxidation of 2-methyl-3-buten-2-ol and its implications for PM2.5 Directory of Open Access Journals (Sweden) W. A. Lonneman 2012-02-01 Full Text Available The formation of secondary organic aerosol (SOA generated by irradiating 2-methyl-3-buten-2-ol (MBO in the presence and/or absence of NOx, H2O2, and/or SO2 was examined. Experiments were conducted in smog chambers operated in either dynamic or static mode. A filter/denuder sampling system was used for simultaneously collecting gas- and particle-phase products. The structural characterization of gas and particulate products was investigated using BSTFA, BSTFA + PFBHA, and DNPH derivatization techniques followed by GC-MS and liquid chromatography analysis. This analysis showed the occurrence of more than 68 oxygenated organic compounds in the gas and particle phases, 28 of which were tentatively identified. The major components observed include 2,3-dihydroxyisopentanol (DHIP, 2-hydroxy-2-oxoisopentanol, 2,3-dihydroxy-3-methylbutanal, 2,3-dihydroxy-2-methylsuccinic acid, 2-hydroxy-2-methylpropanedioic acid, acetone, glyoxal, methylglyoxal, glycolaldehyde, and formaldehyde. Most of these oxygenated compounds were detected for the first time in this study. While measurements of the gas-phase photooxidation products have been made, the focus of this work has been an examination of the particle phase. SOA from some experiments was analyzed for the organic mass to organic carbon ratio (OM/OC, the effective enthalpy of vaporization (ΔHvapeff, and the aerosol yield. Additionally, aerosol size, volume, and number concentrations were measured by a Scanning Mobility Particle Sizer coupled to a Condensation Particle Counter system. The OM/OC ratio was 2.1 in the MBO/H2O2 system. The ΔHvapeff was 41 kJ mol−1, a value similar to that of isoprene SOA. The laboratory SOA yield measured in this study was 0.7% in MBO/H2O2 for an aerosol mass of 33 μg m−3. Secondary organic aerosol was found to be negligible under conditions with oxides of nitrogen (NOx present. Time profiles and proposed reaction schemes are provided for selected compounds. The contribution 16. Antioxidant properties of extracts from buckwheat by-products OpenAIRE Marzanna Hęś; Danuta Górecka; Krzysztof Dziedzic 2012-01-01 Background. In the course of production of buckwheat groats by-products are produced, such as bran and hull, which apart from high content of dietary fi ber, may also constitute valuable sources of antioxidants. The aim of these investigations was to determine the antioxidant activity of extracts from by-products produced during processing of buckwheat for groats. Material and method. Analyses were conducted on bran and hull of buckwheat cv. Kora. Extraction was run using acetone, methanol an... 17. Assessing methane oxidation under landfill covers and its contribution to the above atmospheric CO2 levels: The added value of the isotope (δ13C and δ18O CO2; δ13C and δD CH4) approach International Nuclear Information System (INIS) Highlights: ► Comparison of the isotope and mass balance approaches to evaluate the level of methane oxidation within a landfill. ► The level of methane oxidation is not homogenous under the landfill cover and is strongly correlated to the methane flux. ► Isotope tracking of the contribution of the methane oxidation to the CO2 concentrations in the ambient air. - Abstract: We are presenting here a multi-isotope approach (δ13C and δ18O of CO2; δ13C and δD of CH4) to assess (i) the level(s) of methane oxidation during waste biodegradation and its migration through a landfill cover in Sonzay (France), and (ii) its contribution to the atmospheric CO2 levels above the surface. The isotope approach is compared to the more conventional mass balance approach. Results from the two techniques are comparable and show that the CH4 oxidation under the landfill cover is heterogenous, with low oxidation percentages in samples showing high biogas fluxes, which was expected in clay covers presenting fissures, through which CH4 is rapidly transported. At shallow depth, more immobile biogas pockets show a higher level of CH4 oxidation by the methanotrophic bacteria. δ13C of CO2 samples taken at different heights (from below the cover up to 8 m above the ground level) were also used to identify and assess the relative contributions of its main sources both under the landfill cover and in the surrounding atmosphere. 18. ANALYSIS OF BY-PRODUCTS MARKET IN RUSSIA Directory of Open Access Journals (Sweden) Keniyz N. V. 2015-01-01 Full Text Available Changing style of life, its rhythm and tendencies dictate their own conditions. The deficit of time makes us economize it on all, including the time for cooking. Among the main trends of the domestic meat market - switching consumers from frozen meat products to fresh cooled products. In connection with it the amount of consumers of meat semi-finished products grows. In the work there was considered the results of research of the Russian market of by-products. The market of frozen meat by-products is actively developed in large cities, where it has its own production. The participants of the market state that consumers have started to buy more frozen by-products by weight and the analysis of meat by-products assortment in retailing trade for 2014 testifies it. Trying to fasten their positions, operators of the market not only develop the production powers but work out new products and the analysis of dynamics of production volumes of meat by-products and shares of federal districts – producers of meat by-products testify it. The main players in this segment see the future market for complex, receipt, combined products and ready dishes that will lead to change of structure of meat semi-finished products sales 19. Interpreting the Ultraviolet Aerosol Index Observed with the OMI Satellite Instrument to Understand Absorption by Organic Aerosols: Implications for Atmospheric Oxidation and Direct Radiative Effects Science.gov (United States) Hammer, Melanie S.; Martin, Randall V.; Donkelaar, Aaron van; Buchard, Virginie; Torres, Omar; Ridley, David A.; Spurr, Robert J. D. 2016-01-01 Satellite observations of the ultraviolet aerosol index (UVAI) are sensitive to absorption of solar radiation by aerosols; this absorption affects photolysis frequencies and radiative forcing. We develop a global simulation of the UVAI using the 3-D chemical transport model GEOSChem coupled with the Vector Linearized Discrete Ordinate Radiative Transfer model (VLIDORT). The simulation is applied to interpret UVAI observations from the Ozone Monitoring Instrument (OMI) for the year 2007. Simulated and observed values are highly consistent in regions where mineral dust dominates the UVAI, but a large negative bias (-0.32 to -0.97) exists between simulated and observed values in biomass burning regions. We determine effective optical properties for absorbing organic aerosol, known as brown carbon (BrC), and implement them into GEOS-Chem to better represent observed UVAI values over biomass burning regions. The inclusion of absorbing BrC decreases the mean bias between simulated and OMI UVAI values from -0.57 to -0.09 over West Africa in January, from -0.32 to +0.0002 over South Asia in April, from -0.97 to -0.22 over southern Africa in July, and from -0.50 to +0.33 over South America in September. The spectral dependence of absorption after including BrC in the model is broadly consistent with reported observations for biomass burning aerosol, with absorbing Angstrom exponent (AAE) values ranging from 2.9 in the ultraviolet (UV) to 1.3 across the UV-Near IR spectrum. We assess the effect of the additional UV absorption by BrC on atmospheric photochemistry by examining tropospheric hydroxyl radical (OH) concentrations in GEOS-Chem. The inclusion of BrC decreases OH by up to 30% over South America in September, up to 20% over southern Africa in July, and up to 15% over other biomass burning regions. Global annual mean OH concentrations in GEOS-Chem decrease due to the presence of absorbing BrC, increasing the methyl chloroform lifetime from 5.62 to 5.68 years, thus 20. Interpreting the Ultraviolet Aerosol Index observed with the OMI satellite instrument to understand absorption by organic aerosols: implications for atmospheric oxidation and direct radiative effects Directory of Open Access Journals (Sweden) M. S. Hammer 2015-10-01 Full Text Available Satellite observations of the Ultraviolet Aerosol Index (UVAI are sensitive to absorption of solar radiation by aerosols; this absorption affects photolysis frequencies and radiative forcing. We develop a global simulation of the UVAI using the 3-D chemical transport model GEOS-Chem coupled with the Vector Linearized Discrete Ordinate Radiative Transfer model (VLIDORT. The simulation is applied to interpret UVAI observations from the Ozone Monitoring Instrument (OMI for the year 2007. Simulated and observed values are highly consistent in regions where mineral dust dominates the UVAI, but a large negative bias (−0.32 to −0.97 exists between simulated and observed values in biomass burning regions. We determine effective optical properties for absorbing organic aerosol, known as brown carbon (BrC, and implement them into GEOS-Chem to better represent observed UVAI values over biomass burning regions. The addition of absorbing BrC decreases the mean bias between simulated and OMI UVAI values from −0.57 to −0.09 over West Africa in January, from −0.32 to +0.0002 over South Asia in April, from −0.97 to −0.22 over southern Africa in July, and from −0.50 to +0.33 over South America in September. The spectral dependence of absorption after adding BrC to the model is broadly consistent with reported observations for biomass burning aerosol, with Absorbing Angstrom Exponent (AAE values ranging from 2.9 in the ultraviolet (UV to 1.3 across the UV-Near IR spectrum. We assess the effect of the additional UV absorption by BrC on atmospheric photochemistry by examining tropospheric hydroxyl radical (OH concentrations in GEOS-Chem. The inclusion of BrC decreases OH by up to 35 % over South America in September, up to 25 % over southern Africa in July, and up to 20 % over other biomass burning regions. Global annual mean OH concentrations in GEOS-Chem decrease due to the presence of absorbing BrC, increasing the methyl chloroform lifetime from 5 1. Atmospheric Refraction CERN Document Server Nauenberg, Michael 2016-01-01 Calculations of atmospheric refraction are generally based on a simplified model of atmospheric density in the troposphere which assumes that the temperature decreases at a constant lapse rate from sea level up to a height equal to eleven km, and that afterwards it remains constant. In this model, the temperature divided by the lapse rate determines the length scale in the calculations for altitudes less than this height. But daily balloon measurements across the U.S.A. reveal that in some cases the air temperature actually increases from sea level up to a height of about one km, and only after reaching a plateau, it decreases at an approximately constant lapse rate. Moreover, in three examples considered here, the temperature does not remain constant at eleven km , but continues to decreases to a minimum at about sixteen kilometers , and then increases at higher altitudes at a lower rate. Calculations of atmospheric refraction based on this atmospheric data is compared with the results of simplified models. 2. Atmospheric Dispositifs DEFF Research Database (Denmark) Wieczorek, Izabela 2015-01-01 as a spatial phenomenon, exploring a multiplicity of conditions that constitute their resonant origins – i.e. the production sites from and within they have emerged. The intention is also to argue that despite the fact that atmosphere as an aesthetic category has crystallised over the last few decades... 3. Highly oxidized superconductors Science.gov (United States) Morris, Donald E. 1994-01-01 Novel superconducting materials in the form of compounds, structures or phases are formed by performing otherwise known syntheses in a highly oxidizing atmosphere rather than that created by molecular oxygen at atmospheric pressure or below. This leads to the successful synthesis of novel superconducting compounds which are thermodynamically stable at the conditions under which they are formed. 4. Drinking Water Disinfection by In-line Electrolysis: Product and Inorganic By-Product Formation Science.gov (United States) Bergmann, M. E. Henry This section covers peculiarities of so-called in-line electrolysis when drinking water is electrolysed to produce disinfection species killing microorganisms. Mainly mixed oxide electrodes (MIO) based on IrO2 and/or RuO2 coatings and boron-doped diamond electrodes were used in the studies. Artificial and real drinking water systems were electrolysed in continuous and discontinuous operating mode, varying water composition, current density and electrode materials. Results show, besides the ability of producing active chlorine, risks of inorganic disinfection by-products (DBPs) such as chlorate, perchlorate, nitrite, ammonium, chloramines, hydrogen peroxide and others. DBPs are responsible for analysis errors using DPD method for active chlorine measurements. Geometry may influence by-product yield. As a conclusion, the necessity of developing test routines for practical cell applications must be underlined. 5. Oxidization of squalene, a human skin lipid: a new and reliable marker of environmental pollution studies. Science.gov (United States) Pham, D-M; Boussouira, B; Moyal, D; Nguyen, Q L 2015-08-01 A review of the oxidization of squalene, a specific human compound produced by the sebaceous gland, is proposed. Such chemical transformation induces important consequences at various levels. Squalene by-products, mostly under peroxidized forms, lead to comedogenesis, contribute to the development of inflammatory acne and possibly modify the skin relief (wrinkling). Experimental conditions of oxidation and/or photo-oxidation mechanisms are exposed, suggesting that they could possibly be bio-markers of atmospheric pollution upon skin. Ozone, long UVA rays, cigarette smoke… are shown powerful oxidizing agents of squalene. Some in vitro, ex vivo and in vivo testings are proposed as examples, aiming at studying ingredients or products capable of boosting or counteracting such chemical changes that, globally, bring adverse effects to various cutaneous compartments. PMID:25656265 6. Oxidization of squalene, a human skin lipid: a new and reliable marker of environmental pollution studies. Science.gov (United States) Pham, D-M; Boussouira, B; Moyal, D; Nguyen, Q L 2015-08-01 A review of the oxidization of squalene, a specific human compound produced by the sebaceous gland, is proposed. Such chemical transformation induces important consequences at various levels. Squalene by-products, mostly under peroxidized forms, lead to comedogenesis, contribute to the development of inflammatory acne and possibly modify the skin relief (wrinkling). Experimental conditions of oxidation and/or photo-oxidation mechanisms are exposed, suggesting that they could possibly be bio-markers of atmospheric pollution upon skin. Ozone, long UVA rays, cigarette smoke… are shown powerful oxidizing agents of squalene. Some in vitro, ex vivo and in vivo testings are proposed as examples, aiming at studying ingredients or products capable of boosting or counteracting such chemical changes that, globally, bring adverse effects to various cutaneous compartments. 7. Impact of Amazonian deforestation on atmospheric chemistry OpenAIRE Ganzeveld, L.N.; Lelieveld, J. 2004-01-01 A single-column chemistry and climate model has been used to study the impact of deforestation in the Amazon Basin on atmospheric chemistry. Over deforested areas, daytime ozone deposition generally decreases strongly except when surface wetness decreases through reduced precipitation, whereas nocturnal soil deposition increases. The isoprene and soil nitric oxide emissions decrease although nitrogen oxide release to the atmosphere increases due to reduced canopy deposition. Deforestation als... 8. Atmospheric emission of nitrogen oxide from kraft recovery boilers in Sweden; Kartlaeggning av NO{sub x}-utslaepp fraan sodapannor i Sverige Energy Technology Data Exchange (ETDEWEB) Kjoerk, Anders; Herstad Swaerd, Solvie [S.E.P. Scandinavian Energy Project AB, Goeteborg (Sweden) 2000-05-01 Recovery boiler NO{sub x} emissions are low compared with those from power boilers. However tighter environmental requirements to decrease the acidic emissions implies that all sources have to be addressed. There are an ongoing evaluation and development of NO{sub x} control technologies in the pulp industry. Basically air staging, selective catalytic reduction, SCR, and selective noncatalytic reduction, SNCR, have been discussed. Other NO{sub x} control options may be available as a result of ongoing research and development. As a background in the work to reduce the acid rain it has been considered necessary to have a good picture of the NO{sub x} emission from recovery boilers, and the Thermal Engineering Research Institute in Sweden have therefore sponsored this study. The intention is to give a good general view and try to explain the reasons for the large differences between boilers. Data from the 30 kraft recovery boilers which were in operation in Sweden during 1999 have been collected. Both NO{sub x} levels and specific conditions which could have an influence on the level have been included. The evaluation show a clear correlation between the nitrogen content in the liquor and the NO{sub x} level. It seams also that a long retention time in the furnace give an opportunity to reduce the amount of nitrogen oxide. For most boilers in Sweden the NO{sub x} levels are reported in mg/MJ and comparison could be done between different types of boilers. However for recovery boilers there could be a large uncertainty in the calculation which gives the amount (mg) of NO{sub x}, the definition of the heat input to be used (MJ) is either not clear. As a base for the study the measured concentration in ppm is used instead. The reported values are in the range of 30 - 100 ppm, however the majority of the boilers operate in a more narrow range 60-80 ppm. Air staging and other combustion methods could not reasonably reduce the NO{sub x} emission with more than 20% in the 9. Atmospheric Chemistry and Air Pollution Directory of Open Access Journals (Sweden) Jeffrey S. Gaffney 2003-01-01 Full Text Available Atmospheric chemistry is an important discipline for understanding air pollution and its impacts. This mini-review gives a brief history of air pollution and presents an overview of some of the basic photochemistry involved in the production of ozone and other oxidants in the atmosphere. Urban air quality issues are reviewed with a specific focus on ozone and other oxidants, primary and secondary aerosols, alternative fuels, and the potential for chlorine releases to amplify oxidant chemistry in industrial areas. Regional air pollution issues such as acid rain, long-range transport of aerosols and visibility loss, and the connections of aerosols to ozone and peroxyacetyl nitrate chemistry are examined. Finally, the potential impacts of air pollutants on the global-scale radiative balances of gases and aerosols are discussed briefly. 10. 常压下Pt-Bi双金属催化剂上甘油选择性氧化%Glycerol Oxidation with Oxygen over Bimetallic Pt-Bi Catalysts under Atmospheric Pressure Institute of Scientific and Technical Information of China (English) 梁丹; 崔世玉; 高静; 王军华; 陈平; 侯昭胤 2011-01-01 制备了一系列活性碳(AC)负载的Pt-Bi双金属催化剂,考察了催化剂中Bi含量对其催化甘油选择性氧化反应性能的影响.结果表明,适量Bi的添加可以改善催化剂中Pt的氧化还原性能,从而有利于催化剂活性的提高和二羟基丙酮(DIHA)产物的生成.当Bi的含量为5％时,该催化剂的活性最高,甘油转化率和DIHA选择性分别达到91.5％和49.0％.表征结果显示,Pt-Bi颗粒的平均粒径为3.8 nm,且高度分散在催化剂表面,这是该催化剂具有较高活性的主要原因.%A series of bimetallic Pt-Bi catalysts with a constant platinum content of 5.0 wt% and a varied bismuth content (3.0-7.0 wt%)supported on active carbon were prepared and used for glycerol oxidation with oxygen under atmospheric pressure.The bimetallic Pt-Bi/C was efficient for the selective oxidation of glycerol to dihydroxyacetone (DIHA) and the selectivity for DIHA reached 49.0% at a 91.5%conversion of glycerol over the 5%Pt-5%Bi/C catalyst.X-ray diffraction and transmission electron microscopy analysis revealed that the specially configured Pt-Bi nanoparticles in 5%Pt-5%Bi/C were highly dispersed (3.8 nm) over the active carbon support,which is proposed to contribute to the improved performance. 11. Processes regulating nitric oxide emissions from soils DEFF Research Database (Denmark) Pilegaard, Kim 2013-01-01 Nitric oxide (NO) is a reactive gas that plays an important role in atmospheric chemistry by influencing the production and destruction of ozone and thereby the oxidizing capacity of the atmosphere. NO also contributes by its oxidation products to the formation of acid rain. The major sources... 12. Estimating indirect land use impacts from by-products utilization Energy Technology Data Exchange (ETDEWEB) Croezen, H.; Brouwer, F. 2008-06-15 Aim of this project part is providing an indication of the effects utilization of by-products from biofuels production can have on global land use and on land use changes. Potential influences on land use changes may also influence net GHG emissions, in case deforestation or other forms of changing natural habitats into crop land are avoided. In order to demonstrate the relevance we broadly translated avoided land use in potential GHG emission avoidance due to avoiding land use change. The analysis focuses on the utilization of by-products from so-called first generation biofuels production technologies as feed. This application avoids cultivation of primary feed crops such as soy, wheat and corn and thus reduces area requirement for cultivation of these crops and the GHG emissions related to crop cultivation and crop processing. Reduction in area requirement might also mean avoiding creation of extra agricultural area by transforming natural area's. This would avoid GHG emissions related to land use change. The by-products could alternatively be utilized as fuel or - in the future - as feedstock for second generation biofuels. By-products utilization as fuel will avoid fossil fuel consumption and related GHG emissions. The analysis is a follow up of the E4Tech scenario analysis. We used the amounts of crops applied as feedstocks in the E4Tech scenario's as starting point of our own analysis. In chapter 2 we estimate the amounts of by-products we have to consider. In chapter 3 we then estimate which amounts of primary feed crops are likely to be replaced by the considered amounts of by-products. 13. Producing Fish Protein Hydrolysates from Mackerel By-Products OpenAIRE Ana Luísa De Sousa Augusto 2014-01-01 Portugal is one of the largest consumers of fishery products in Europe. This consumption involves a large amount of discarded raw material, such as rejected fish in selling auctions and the generation of by-products in industrial production processes. The by-products in the canning industry alone reach 40% of the raw material, while the frozen fish industries may reach 10-50% of the raw material (INE, 2013). Fish protein hydrolysates (FPH) are one of the most promising technologies for th... 14. Strategies For Turkish Automotive By-Products Industry Directory of Open Access Journals (Sweden) Hakan Bütüner 2012-06-01 Full Text Available Automotive industry is comprised of the industry which produces vehicles, and the industry which, as dominated by Small and Medium Scale Enterprises, produces parts, modules, and systems of such vehicles according to the technical documentation. Having been established through technical and economic supports of the major manufacturers, and developed in the course of time, the by products industry is involved its activities as a significant potential for the domestic economy at present. In this article, general characteristics of Turkish automative by products industry, its weak aspects, aspects need to be improved, and dominant strategies that need to be considered for the improvement are discussed. 15. Atmospheric soundings from Mount Abu Science.gov (United States) Sharma, Som; Sinha, H. S. S. 2005-06-01 An atmospheric science laboratory was set up at Gurushikhar, in the campus of PRL's Infrared observatory, in 1994. A variety of scientific instruments were housed in the atmospheric science laboratory to explore the Earth's ionosphere and neutral atmosphere. A powerful Nd-YAG laser based Lidar, a multi-wavelength all sky imaging system, Day-night-airglow photometer/spectrometer and a proton precession magnetometer are in operation along with a surface ozone sampler, a carbon mono-oxide analyzer and a UV radiometer (measures solar ultraviolet irradiance between 280 and 320 nm). This article highlights the neutral density and temperature measurements by the lidar as well as Atmospheric/Ionospheric parameters derived by other instruments. 16. Total Sulfur Deposition (wet+dry) from the Atmosphere Data.gov (United States) U.S. Environmental Protection Agency — Sulfur Dioxide (SO2) is emitted primarily as a by-product of coal combustion from power plants. Sulfur Dioxide reacts in the atmosphere to form other chemical such... 17. Nutritional Value of Irradiated Animal Feed By-Products International Nuclear Information System (INIS) Animal feed by-products, widely used in animal diets, are sources of disease organisms for animals and for human beings. Salmonella is the principal genus of concern.Radiation treatment (radicidation, radurization) is a promising method of decontamination of feed ingredients. Commercial samples of fish, meat, and blood meals were sealed by heat in polyethylene bags and irradiated at dose levels of 5.0, 10, 20 and 50 kGy. Their chemical analysis were carried out according to A. O. A.C [1] and the total protein efficiency (TPE) of the three animal feed by-products was determined according to Wood ham (2) by using one day old Dokki-4 chicks. Radiation induced an insignificant effect on the chemical constituent of meals. Also, the same trend was observed with TPE of both fish and meat meals. However, irradiation treatments improved TPE values of irradiated blood meal samples. From the results, it could be concluded that irradiation of animal feed by-products up to a dose level of 50 Gy has no adverse effects on the nutritional value of animal feed by-products 18. REDUCTION OF DISINFECTION BY-PRODUCT PERCURSORS BY NANOFILTRATION Science.gov (United States) The reduction of disinfection by-product (DBP) precursors by nanofiltration was investigated in Florida at both a groundwater site and a surface water site. eparate studies, involving pilot plant operations, were conducted for one year at each site. he principal research tasks at... 19. Maximizing Utilization of Energy from Crop By-products Directory of Open Access Journals (Sweden) Budi Haryanto 2014-03-01 Full Text Available The availability of crop by-products is huge during harvesting times as related to the vast agricultural land area; however, their utilization is still limited due to lack of knowledge and handling problem. Seasonal effect is obvious especially during wet season when high rainfall hinders proper management of crop by-products. Crop by-products are energy rich feedstuffs in the form of chemical substance such as cellulose and hemicellulose. The utilization of cellulose and hemicellulose as sources of energy can be maximized by the application of technologies to increase the digestibility. Cellulose is polymer of glucose while hemicellulose is polymer of xylose which both can be converted to volatile fatty acids by rumen microbial enzyme activities and subsequently used by the host animal as source of energy. In addition, cellulose and hemicellulose can also be used as substrates for bioethanol production leaving behind residual matter with higher concentration of protein which is also appropriate for ruminant feeds. The fat content of crop by-products such as those in rice bran and corn germ can be extracted for oil production that can be used for human consumption with concomitant production of high nutritive value of residues for ruminant feeds. The oil extraction technologies are available; however the high cost of ethanol and oil production should obtain high attention to make the technologies more applicable at farmers’ level. 20. Genotoxicity of Disinfection By-products: Comparison to Carcinogenicity Science.gov (United States) Disinfection by-products (DBPs) can be formed when water is disinfected by various agents such as chlorine, ozone, or chloramines. Among the >600 DBPs identified in drinking water, 11 are regulated by the U.S. Environmental Protection Agency, and another ~70 DBPs that occur at s... 1. Impacts of drinking water pretreatments on the formation of nitrogenous disinfection by-products. Science.gov (United States) Chu, Wenhai; Gao, Naiyun; Deng, Yang; Templeton, Michael R; Yin, Daqiang 2011-12-01 The formation of disinfection by-products (DBPs), including both nitrogenous DBPs (N-DBPs) and carbonaceous DBPs (C-DBPs), was investigated by analyzing chlorinated water samples following the application of three pretreatment processes: (i) powdered activated carbon (PAC) adsorption; (ii) KMnO(4) oxidation and (iii) biological contact oxidation (BCO), coupled with conventional water treatment processes. PAC adsorption can remove effectively the precursors of chloroform (42.7%), dichloroacetonitrile (28.6%), dichloroacetamide (DCAcAm) (27.2%) and trichloronitromethane (35.7%), which were higher than that pretreated by KMnO(4) oxidation and/or BCO process. The removal efficiency of dissolved organic carbon by BCO process (76.5%)--was superior to that by PAC adsorption (69.9%) and KMnO(4) oxidation (61.4%). However, BCO increased the dissolved organic nitrogen (DON) concentration which caused more N-DBPs to be formed during subsequent chlorination. Soluble microbial products including numerous DON compounds were produced in the BCO process and were observed to play an essential role in the formation of DCAcAm in particular. PMID:22014706 2. Ozone and hydrogen peroxide applications for disinfection by-products control in drinking water International Nuclear Information System (INIS) A great interest has been developed during the last years for ozone in drinking water treatments thanks to its strong oxidant and disinfectant power and for its efficiency in disinfection by-products (DBPs) precursors removal. However ozonization produces some specific DBPs, such as aldehydes and ketones; moreover, the presence of bromide in raw water engages ozone in a complex cycle in which both organic bromide and inorganic bromate are end products. In this paper the combination of hydrogen peroxide with ozone (known as peroxone process) and the ozone alone process were experimented on one surface water coming from the lake of Brugneto (Genova) in order to investigate bromate formation and trihalomethanes precursors removal during the oxidation process. The results show that the advanced peroxone process can be applied for bromate reduction (about 30-40%) with better results in comparison with the ozone alone process, while no advantages are shown for THMs precursors removal. The addition of in-line filtration step after pre-oxidation improves both bromate and THMs precursors removal, particularly with increasing hydrogen peroxide/ozone ratio in the oxidation step 3. Land application uses for dry FGD by-products Energy Technology Data Exchange (ETDEWEB) Bigham, J.; Dick, W.; Forster, L.; Hitzhusen, F.; McCoy, E.; Stehouwer, R.; Traina, S.; Wolfe, W. (Ohio State Univ., Columbus, OH (United States)); Haefner, R. (Geological Survey, Columbus, OH (United States). Water Resources Div.) 1993-04-01 The 1990 amendments to the Clean Air Act have spurred the development of flue gas desulfurization (FGD) processes, several of which produce a dry, solid by-product material consisting of excess sorbent, reaction products containing sulfates and sulfites, and coal fly ash. Presently FGD by-product materials are treated as solid wastes and must be landfilled. However, landfill sites are becoming more scarce and tipping fees are constantly increasing. It is, therefore, highly desirable to find beneficial reuses for these materials provided the environmental impacts are minimal and socially acceptable. Phase 1 results of a 4 and 1/2 year study to demonstrate large volume beneficial uses of FGD by-products are reported. The purpose of the Phase 1 portion of the project was to characterize the chemical, physical, mineralogical and engineering properties of the FGD by-product materials obtained from various FGD technologies being developed in the state of Ohio. Phase 1 also involved the collection of baseline economic data related to the beneficial reuse of these FGD materials. A total of 58 samples were collected and analyzed. In summary Phase 1 results revealed that FGD by-product materials are essentially coal fly ash materials diluted with unreacted sorbent and reaction products. High volume beneficial reuses will depend on the economics of their substituting for existing materials for various types of applications (e.g. as an agricultural liming material, soil borrow for highway embankment construction, and reclamation of active and abandoned surface coal mines). Environmental constraints to the beneficial reuse of dry FGD byproduct materials, based on laboratory and leachate studies, seem to be less than for coal fly ash. 4. Does KMnO4 preoxidation reduce the genotoxicity of disinfection by-products? Science.gov (United States) Chang, Yangyang; Bai, Yaohui; Qu, Jiuhui 2016-11-01 Potassium permanganate (KMnO4) preoxidation is capable of affecting the formation of disinfection by-products (DBPs). However, few studies have focused on the toxicity of DBPs after KMnO4 preoxidation, which is an important index to evaluate alternative treatment processes. Herein genotoxicity (SOS/umu test) was used to clarify the impact of KMnO4 preoxidation on the chlorination byproducts produced from two representative precursors, tyrosine (Tyr) and 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid (BP-4), and their mixture. Results revealed that although KMnO4 could not oxidize BP-4, after chlorination KMnO4 could oxidize the chlorination byproducts of BP-4 and thus decrease the genotoxicity production. For Tyr, KMnO4 preoxidation could increase or decrease the genotoxicity of DBPs, depending on the KMnO4 dose. The optimal initial molar ratio of KMnO4 to Tyr was confirmed to be 1:1. It has been proved that both the oxidation of Tyr by KMnO4 and manganese dioxide (MnO2, the reduction product of KMnO4) and the oxidation of chlorination byproducts by MnO2 can decrease the genotoxicity production of chlorinated Tyr. Remarkably, during chlorination, the competition of manganese(II) oxidation with organic oxidation can result in less chlorine reacting with organics, to induce an increase in genotoxicity. This is the main cause for the increase in genotoxicity of chlorinated Tyr after KMnO4 preoxidation. Additionally, the genotoxicity of the chlorinated mixture was shifted from being higher than the sum of individual genotoxicities of the chlorinated precursors to being lower than their sum with increasing KMnO4 dosage, due to the combined effects between the preoxidation-chlorination products from the two compounds. PMID:27521641 5. Bioassay-guided fractionation of a hepatoprotective and antioxidant extract of pea by-product. Science.gov (United States) Seida, Ahmed A; El Tanbouly, Nebal D; Islam, Wafaa T; Eid, Hanaa H; El Maraghy, Shohda A; El Senousy, Amira S 2015-01-01 The hepatoprotective and antioxidant activities of the hydroalcoholic extract (PE) of pea (Pisum sativum L.) by-product were evaluated, using CCl4-induced oxidative stress and hepatic damage in rats. These activities were assessed via measuring alanine aminotransferase (ALT), aspartate aminotransferase (AST), total protein and albumin, malondialdehyde (MDA), reduced glutathione (GSH), protein thiols (PSH), nitrite/nitrate levels, glutathione-peroxidase (GSH-Px), glutathione-S-transferase (GST) activities, as well as, histopathological evaluation. PE revealed significant hepatoprotective and antioxidant activities mostly found in n-butanol fraction. Chromatographic fractionation of this active fraction led to the isolation of five flavonoid glycosides namely, quercetin-3-O-sophorotrioside (1), quercetin-3-O-rutinoside (2), quercetin-3-O-(6″″-O-E sinapoyl)-sophorotrioside (3), quercetin-3-O-(6″″-O-E feruloyl)-sophorotrioside (4) and quercetin-3-O-β-D-glucopyranoside (5). The isolated compounds were quantified in PE, using a validated HPLC method and the nutritional composition of pea by-product was also investigated. Our results suggest that pea by-product contained biologically active constituents which can be utilised to obtain high value added products for nutraceutical use. 6. Atmospheric influence of Earth's earliest sulfur cycle Science.gov (United States) Farquhar; Bao; Thiemens 2000-08-01 Mass-independent isotopic signatures for delta(33)S, delta(34)S, and delta(36)S from sulfide and sulfate in Precambrian rocks indicate that a change occurred in the sulfur cycle between 2090 and 2450 million years ago (Ma). Before 2450 Ma, the cycle was influenced by gas-phase atmospheric reactions. These atmospheric reactions also played a role in determining the oxidation state of sulfur, implying that atmospheric oxygen partial pressures were low and that the roles of oxidative weathering and of microbial oxidation and reduction of sulfur were minimal. Atmospheric fractionation processes should be considered in the use of sulfur isotopes to study the onset and consequences of microbial fractionation processes in Earth's early history. 7. Atmospheric pseudohalogen chemistry Directory of Open Access Journals (Sweden) D. J. Lary 2004-09-01 Full Text Available There are at least three reasons why hydrogen cyanide is likely to be significant for atmospheric chemistry. The first is well known, HCN is a product and marker of biomass burning. However, if a detailed ion chemistry of lightning is considered then it is almost certain than in addition to lightning producing NOx, it also produces HOx and HCN. Unlike NOx and HOx, HCN is long-lived and could therefore be a useful marker of lightning activity. Observational evidence is considered to support this view. Thirdly, the chemical decomposition of HCN leads to the production of small amounts of CN and NCO. NCO can be photolyzed in the visible portion of the spectrum yielding N atoms. The production of N atoms is significant as it leads to the titration of nitrogen from the atmosphere via N+N→N2. Normally the only modelled source of N atoms is NO photolysis which happens largely in the UV Schumann-Runge bands. However, NCO photolysis occurs in the visible and so could be involved in titration of atmospheric nitrogen in the lower stratosphere and troposphere. HCN emission inventories are worthy of attention. The CN and NCO radicals have been termed pseudohalogens since the 1920s. They are strongly bound, univalent, radicals with an extensive and varied chemistry. The products of the atmospheric oxidation of HCN are NO, CO and O3. N+CH4 and N+CH3OH are found to be important sources of HCN. Including the pseudohalogen chemistry gives a small increase in ozone and total reactive nitrogen (NOy. 8. Disinfection by-products in ballast water treatment: an evaluation of regulatory data. Science.gov (United States) Werschkun, Barbara; Sommer, Yasmin; Banerji, Sangeeta 2012-10-15 To reduce the global spread of invasive aquatic species, international regulations will soon require reductions of the number of organisms in ballast water discharged by ships. For this purpose, ballast water treatment systems were developed and approved by an international procedure. These systems rely on established water treatment principles which, to different degrees, have been proven to generate disinfection by-products with hazardous properties but have only scarcely been investigated in marine environments. Our study evaluates the publicly available documentation about approved ballast water treatment systems with regard to by-product formation. The most commonly employed methods are chlorination, ozonation, and ultraviolet (UV) irradiation. Chlorination systems generate trihalomethanes, halogenated acetic acids, and bromate in substantially larger quantities than reported for other areas of application. Levels are highest in brackish water, and brominated species predominate, in particular bromoform and dibromoacetic acid. Ozonation, which is less frequently utilized, produces bromoform in lower concentrations but forms higher levels of bromate, both of which were effectively reduced by active carbon treatment. In systems based on UV radiation, medium pressure lamps are employed as well as UV-induced advanced oxidation. For all UV systems, by-product formation is reported only occasionally. The most notable observations were small increases in nitrite, hydrogen peroxide, halogenated methanes and acetic acids. The assessment of by-product formation during ballast water treatment is limited by the lacking completeness and quality of available information. This concerns the extent and statistical characterisation of chemical analysis as well as the documentation of the test water parameters. 9. Energy applications of olive-oil industry by-products: 1. The exhaust foot cake Energy Technology Data Exchange (ETDEWEB) Masghouni, M. [Ecole Nationale des Ingenieurs de Tunis, Belvedere (Tunisia). Laboratoire de synthese et d' analyse des materiaux; Hassairi, M. [Ecole Nationale des Ingenieurs de Tunis, Belvedere (Tunisia). Laboratoire de thermique industrielle 2000-07-01 The energy characteristics of the exhaust foot cake (EFC) from the olive-oil extraction industry are described in this paper. This biomass has proved to be an interesting energy source. The use of this solid-waste as a combustible in brick manufacture is economically profitable: 1100 tons of EFC yearly substitute 420 EOT of No. 2 heavy fuel containing 4% of sulphur. The use of this solid-waste as an energy source is environment friendly, as it reduces the nuisance of solid-waste and gas emissions to the atmosphere, particularly sulphur oxides. (author) 10. Utilization of biodiesel by-products for mosquito control. Science.gov (United States) Pant, Megha; Sharma, Satyawati; Dubey, Saurabh; Naik, Satya Narayan; Patanjali, Phool Kumar 2016-03-01 The current paper has elaborated the efficient utilization of non-edible oil seed cakes (NEOC), by-products of the bio-diesel extraction process to develop a herbal and novel mosquitocidal composition against the Aedes aegypti larvae. The composition consisted of botanical active ingredients, inerts, burning agents and preservatives; where the botanical active ingredients were karanja (Pongamia glabra) cake powder and jatropha (Jatropha curcas) cake powder, products left after the extraction of oil from karanja and jatropha seed. The percentage mortality value recorded for the combination with concentration, karanja cake powder (20%) and jatropha cake powder (20%), 1:1 was 96%. The coil formulations developed from these biodiesel by-products are of low cost, environmentally friendly and are less toxic than the synthetic active ingredients. PMID:26296531 11. The origins of religion: evolved adaptation or by-product? Science.gov (United States) Pyysiäinen, Ilkka; Hauser, Marc 2010-03-01 Considerable debate has surrounded the question of the origins and evolution of religion. One proposal views religion as an adaptation for cooperation, whereas an alternative proposal views religion as a by-product of evolved, non-religious, cognitive functions. We critically evaluate each approach, explore the link between religion and morality in particular, and argue that recent empirical work in moral psychology provides stronger support for the by-product approach. Specifically, despite differences in religious background, individuals show no difference in the pattern of their moral judgments for unfamiliar moral scenarios. These findings suggest that religion evolved from pre-existing cognitive functions, but that it may then have been subject to selection, creating an adaptively designed system for solving the problem of cooperation. 12. Utilization of biodiesel by-products for mosquito control. Science.gov (United States) Pant, Megha; Sharma, Satyawati; Dubey, Saurabh; Naik, Satya Narayan; Patanjali, Phool Kumar 2016-03-01 The current paper has elaborated the efficient utilization of non-edible oil seed cakes (NEOC), by-products of the bio-diesel extraction process to develop a herbal and novel mosquitocidal composition against the Aedes aegypti larvae. The composition consisted of botanical active ingredients, inerts, burning agents and preservatives; where the botanical active ingredients were karanja (Pongamia glabra) cake powder and jatropha (Jatropha curcas) cake powder, products left after the extraction of oil from karanja and jatropha seed. The percentage mortality value recorded for the combination with concentration, karanja cake powder (20%) and jatropha cake powder (20%), 1:1 was 96%. The coil formulations developed from these biodiesel by-products are of low cost, environmentally friendly and are less toxic than the synthetic active ingredients. 13. Soil surface properties affected by organic by-products OpenAIRE Pachepsky Ya.A.; Rawls W.J.; Fournier L.L.; Filgueira R.R.; Sikora L.J. 2002-01-01 The beneficial effects of amending soils with organic by-products include improvement of both chemical and physical factors. Very few studies have investigated changes in the soil specific surface area (SSA) after amendments with manures or composts. Soil samples were taken from plots before and after four years� application of manures, composts or nitrogen fertilizer. A corn-wheat-soybean rotation was grown. Soil samples were tested for changes in water retention at �15 bar, bu... 14. By-products from Fish Processing: Focus on French Industry OpenAIRE Penven, Anais; Perez-galvez, Raul; Berge, Jean-pascal 2013-01-01 Biotechnology advances for marine by-products conversion into products of interest are numerous. In order to give maximum elements of understanding, it is essential to define the framework of this research to understand why and how bioconversion technologies are applicable. It is essential to look beyond the technical and technological advances on the subject and so to take into account the economic, social, political and environmental parameters, which govern all forms of approaches for fish... 15. Health impact of disinfection by-products in swimming pools OpenAIRE Villanueva, Cristina M.; Laia Font-Ribera 2012-01-01 This article is focused on the epidemiological evidence on the health impacts related to disinfection by-products (DBPs) in swimming pools, which is a chemical hazard generated as an undesired consequence to reduce the microbial pathogens. Specific DBPs are carcinogenic, fetotoxic and/or irritant to the airways according to experimental studies. Epidemiological evidence shows that swimming in pools during pregnancy is not associated with an increased risk of reproductive outcomes. An epidemio... 16. Effect of Celebrity Endorsement in Advertising Activities by Product Type OpenAIRE Karasiewicz Grzegorz; Kowalczuk Martyna 2014-01-01 This article seeks to answer two related questions: are celebrity endorsements more likely to be result in a higher evaluation of the product being advertised than use of an anonymous individual (e.g. a typical consumer); and, if present, do these positive effects vary by product category? To answer these two questions research was conducted on a 237 student sample employing a quasi-experiment consisting of four groups (two product categories and two types of endorsers) using data collected t... International Nuclear Information System (INIS) Work under the Radiolytic Oxidation Contract from 1986 until April 1989 is reported. The effects of alpha- and gamma-irradiation on the chemistries of plutonium, neptunium and technetium, under conditions representative of the near fields of intermediate and high level waste repositories, were investigated. Gamma-radiolysis of Np (IV) results in oxidation in solutions below pH 12. Solutions of Tc (VII) are reduced to Tc (IV) by gamma-irradiation in contact with blast furnace slag/ordinary Portland cement under an inert atmosphere but not when in contact with pulverized fuel ash/ordinary Portland cement. Tc (IV) is shown to be susceptible to oxidation by the products of the alpha-radiolysis of water. The results of 'overall effects' experiments, which combined representative components of typical ILW or HLW near fields, supported these observations and also showed enhanced plutonium concentrations in alpha-irradiated, HLW simulations. Mathematical models of the behaviour of plutonium and neptunium during gamma-radiolysis have been developed and indicate that oxidation to Pu (VI) is possible at dose rates typical of those expected for HLW. Simulations at ILW dose rates have indicated some effect upon the speciation of neptunium. Laboratory studies of the gamma-irradiation of Np (IV) in bentonite-equilibrated water have also been modelled. Computer code used: PHREEQE, 8 Figs.; 48 Tabs.; 38 refs 18. New insights into meat by-product utilization. Science.gov (United States) Toldrá, Fidel; Mora, Leticia; Reig, Milagro 2016-10-01 Meat industry generates large volumes of by-products like blood, bones, meat trimmings, skin, fatty tissues, horns, hoofs, feet, skull and viscera among others that are costly to be treated and disposed ecologically. These costs can be balanced through innovation to generate added value products that increase its profitability. Rendering results in feed ingredients for livestock, poultry and aquaculture as well as for pet foods. Energy valorization can be obtained through the thermochemical processing of meat and bone meal or the use of waste animal fats for the production of biodiesel. More recently, new applications have been reported like the production of polyhydroxyalkanoates as alternative to plastics produced from petroleum. Other interesting valorization strategies are based on the hydrolysis of by-products to obtain added value products like bioactive peptides with relevant physiological effects as antihypertensive, antioxidant, antidiabetic, antimicrobial, etc. with promising applications in the food, pharmaceutical and cosmetics industry. This paper reports and discusses the latest developments and trends in the use and valorisation of meat industry by-products. PMID:27156911 International Nuclear Information System (INIS) Although no decision has been made to reprocess irradiated CANDU fuel, by-product separation research has recently been initiated in Canada because of its potential importance to Canadian research programs in advanced fuel cycles (especially U/Pu cycle development in the near term) and nuclear waste management. In addition, separated by-products could have a significant commercial potential. Demonstrated applications include: heat sources, gamma radiation sources, light sources, new materials for productions of other useful isotopes, etc. For illustrative purposes the calculated market value of by-products currently stored in irradiated CANDU fuel is approximately $210/kgU. Ontario Hydro has initiated a program to study the application of new separation technolgies, such as laser-based techniques and the plasma ion cyclotron resonance separation technique, to either augment and/or supplant the chemical extraction methods. The main goal is to develop new, more economical extraction methods in order to increase the magnitude of the advantages resulting from this approach to reprocessing. (author) 20. Assessing methane oxidation under landfill covers and its contribution to the above atmospheric CO{sub 2} levels: The added value of the isotope ({delta}{sup 13}C and {delta}{sup 18}O CO{sub 2}; {delta}{sup 13}C and {delta}D CH{sub 4}) approach Energy Technology Data Exchange (ETDEWEB) Widory, D., E-mail: d.widory@brgm.fr [BRGM, 3 ave Claude Guillemin, 45000 Orleans (France); Proust, E.; Bellenfant, G. [BRGM, 3 ave Claude Guillemin, 45000 Orleans (France); Bour, O. [INERIS, Parc Technologique ALATA, 60550 Verneuil-en-Halatte (France) 2012-09-15 Highlights: Black-Right-Pointing-Pointer Comparison of the isotope and mass balance approaches to evaluate the level of methane oxidation within a landfill. Black-Right-Pointing-Pointer The level of methane oxidation is not homogenous under the landfill cover and is strongly correlated to the methane flux. Black-Right-Pointing-Pointer Isotope tracking of the contribution of the methane oxidation to the CO{sub 2} concentrations in the ambient air. - Abstract: We are presenting here a multi-isotope approach ({delta}{sup 13}C and {delta}{sup 18}O of CO{sub 2}; {delta}{sup 13}C and {delta}D of CH{sub 4}) to assess (i) the level(s) of methane oxidation during waste biodegradation and its migration through a landfill cover in Sonzay (France), and (ii) its contribution to the atmospheric CO{sub 2} levels above the surface. The isotope approach is compared to the more conventional mass balance approach. Results from the two techniques are comparable and show that the CH{sub 4} oxidation under the landfill cover is heterogenous, with low oxidation percentages in samples showing high biogas fluxes, which was expected in clay covers presenting fissures, through which CH{sub 4} is rapidly transported. At shallow depth, more immobile biogas pockets show a higher level of CH{sub 4} oxidation by the methanotrophic bacteria. {delta}{sup 13}C of CO{sub 2} samples taken at different heights (from below the cover up to 8 m above the ground level) were also used to identify and assess the relative contributions of its main sources both under the landfill cover and in the surrounding atmosphere. 1. Effects of heat-treatment atmosphere on electrochemical performances of Ni-rich mixed-metal oxide (LiNi0.80Co0.15Mn0.05O2) as a cathode material for lithium ion battery International Nuclear Information System (INIS) Ni-rich mixed metal oxides (LiNi0.80Co0.15Mn0.05O2) as a high capacity cathode material for lithium ion battery are synthesized in two different heat-treatment atmospheres of air and oxygen, respectively. A cell with LiNi0.80Co0.15Mn0.05O2 heat-treated in the oxygen atmosphere shows better electrochemical performance of initial (193.7 mAh/g) and retention (185.2 mAh/g) capacities than a cell with the cathode material heat-treated in the air atmosphere (initial capacity: 185.2 mAh/g and retention capacity: 172.0 mAh/g). In order to find the reasons of the different electrochemical performance, the samples have been characterized in detail by X-ray diffraction and scanning electron microscopy. The structural differences are revealed at the nanometer scale from the experimental works of scanning transmission electron microscopy images mapped with orientation and reliability indices and electron energy loss spectroscopy. The NiO phase of the rock salt structure is considerably developed on the surfaces of the materials in the less oxidative environment of the air atmosphere; this is related to the poor electrochemical performances 2. Total Nitrogen Deposition (wet+dry) from the Atmosphere Data.gov (United States) U.S. Environmental Protection Agency — Oxides of Nitrogen are emitted primarily as by-products of combustion. Sources include power plants, industrial boilers, and automobiles. In addition, agricultural... 3. Antioxidant properties of extracts from buckwheat by-products Directory of Open Access Journals (Sweden) Marzanna Hęś 2012-06-01 Full Text Available Background. In the course of production of buckwheat groats by-products are produced, such as bran and hull, which apart from high content of dietary fi ber, may also constitute valuable sources of antioxidants. The aim of these investigations was to determine the antioxidant activity of extracts from by-products produced during processing of buckwheat for groats. Material and method. Analyses were conducted on bran and hull of buckwheat cv. Kora. Extraction was run using acetone, methanol and water at room temperature for 24 h. The level of phenolics was determined spectrophotometrically with the Folin-Ciocalteau reagent, using (+ catechin as a standard. Antioxidant activity of extracts was analysed in relation to linoleic acid, running incubation for 19 h, by scavenging of stable radicals of DPPH (2,2-diphenyl-1-picrylhydrazyl and on the basis of metal chelating ability. Recorded results were compared with the activity of BHT (butylated hydroxytoluene. Results. The highest content of polyphenols was found in the methanol extract of hull (168.5 mg/g d.m., which was also characterised by the best antiradical properties. The lowest content of total phenols was found for water extracts of bran after grinding and fi nal bran, at 20.3 mg/g d.m. and 10.2 mg/g d.m. In the emulsion system the highest activity was found for methanol extracts of hull and bran after grinding (Wo = 0.89, as well as the extract of fi nal bran (Wo = 0.85. A higher chelating ability in relation to Fe (II ions was observed for bran extracts (after grinding – 76.1%, fi nal bran – 62.2% than for hull extracts (26%. Conclusions. Extracts obtained from by-products of buckwheat were characterised by high antioxidant activity in the applied model systems. 4. Atmospheric chemistry in volcanic plumes. Science.gov (United States) von Glasow, Roland 2010-04-13 Recent field observations have shown that the atmospheric plumes of quiescently degassing volcanoes are chemically very active, pointing to the role of chemical cycles involving halogen species and heterogeneous reactions on aerosol particles that have previously been unexplored for this type of volcanic plumes. Key features of these measurements can be reproduced by numerical models such as the one employed in this study. The model shows sustained high levels of reactive bromine in the plume, leading to extensive ozone destruction, that, depending on plume dispersal, can be maintained for several days. The very high concentrations of sulfur dioxide in the volcanic plume reduces the lifetime of the OH radical drastically, so that it is virtually absent in the volcanic plume. This would imply an increased lifetime of methane in volcanic plumes, unless reactive chlorine chemistry in the plume is strong enough to offset the lack of OH chemistry. A further effect of bromine chemistry in addition to ozone destruction shown by the model studies presented here, is the oxidation of mercury. This relates to mercury that has been coemitted with bromine from the volcano but also to background atmospheric mercury. The rapid oxidation of mercury implies a drastically reduced atmospheric lifetime of mercury so that the contribution of volcanic mercury to the atmospheric background might be less than previously thought. However, the implications, especially health and environmental effects due to deposition, might be substantial and warrant further studies, especially field measurements to test this hypothesis. 5. Utilization of Biodiesel By-Products for Biogas Production Directory of Open Access Journals (Sweden) Nina Kolesárová 2011-01-01 Full Text Available This contribution reviews the possibility of using the by-products from biodiesel production as substrates for anaerobic digestion and production of biogas. The process of biodiesel production is predominantly carried out by catalyzed transesterification. Besides desired methylesters, this reaction provides also few other products, including crude glycerol, oil-pressed cakes, and washing water. Crude glycerol or g-phase is heavier separate liquid phase, composed mainly by glycerol. A couple of studies have demonstrated the possibility of biogas production, using g-phase as a single substrate, and it has also shown a great potential as a cosubstrate by anaerobic treatment of different types of organic waste or energy crops. Oil cakes or oil meals are solid residues obtained after oil extraction from the seeds. Another possible by-product is the washing water from raw biodiesel purification, which is an oily and soapy liquid. All of these materials have been suggested as feasible substrates for anaerobic degradation, although some issues and inhibitory factors have to be considered. 6. Reducing the formation of disinfection by-products by pre-ozonation. Science.gov (United States) Chang, Cheng-Nan; Ma, Ying-Shih; Zing, Fang-Fong 2002-01-01 The objective of this study is to apply the pre-ozonation process to reduce the formation of disinfection by-products (DBPs). The raw water sample, collected from the Te-Chi Reservoir in central Taiwan, has been polluted by fertilizer. Three types of resins were used to isolate the natural organic matter into seven types of organic fractions. The pre-ozonation was used to oxidize each organic fraction to study the reduction of DBPs of each fraction. Experimental results indicated that the pre-ozonation could reduce the concentration of dissolved organic carbon resulting in the reduction of DBP formation. With the pre-ozonation, 9-54% of DOC and more than 40% of DBPs were reduced. With the analysis of UV adsorption and Fourier transform infrared spectrometer (FTIR), the reduction of A254 and unsaturated functional groups such as aromatic ring and C=C bond containing in the water sample is the major reaction mechanism. 7. Prospects for enhancing carbon sequestration and reclamation of degraded lands with fossil-fuel combustion by-products International Nuclear Information System (INIS) Concern for the potential global change consequences of increasing atmospheric CO2 has prompted interest in the development of mechanisms to reduce or stabilize atmospheric CO2. During the next several decades, a program focused on terrestrial sequestration processes could make a significant contribution to abating CO2 increases. The reclamation of degraded lands, such as mine-spoil sites, highway rights-of-way, and poorly managed lands, represents an opportunity to couple C sequestration with the use of fossil-fuel and energy by-products and other waste material, such as biosolids and organic wastes from human and animal sewage treatment facilities, to improve soil quality. Degraded lands are often characterized by acidic pH, low levels of key nutrients, poor soil structure, and limited moisture-retention capacity. Much is known about the methods to improve these soils, but the cost of implementation is often a limiting factor. However, the additional financial and environmental benefits of C sequestration may change the economics of land reclamation activities. The addition of energy-related by-products can address the adverse conditions of these degraded lands through a variety of mechanisms, such as enhancing plant growth and capturing of organic C in long-lived soil C pools. This review examines the use of fossil-fuel combustion by-products and organic amendments to enhance C sequestration and identifies the key gaps in information that still must be addressed before these methods can be implemented on an environmentally meaningful scale. (author) 8. The alkaline comet assay used in evaluation of genotoxic damage of drinking water disinfection by-products (bromoform and chloroform Directory of Open Access Journals (Sweden) Messaouda Khallef 2015-06-01 Full Text Available The alkaline comet assay (pH 12.3 is a useful method for monitoring genotoxic effects of environmental pollutants in the root nuclei of Allium cepa and various plants; it allows the detection of single- and double-strand breaks, incomplete excision-repair sites and cross-links. It has been introduced to detect even small changes in DNA structure. It is a technically simple, highly sensitive, fast and economic test which detects in vitro and in vivo genotoxicity (DNA integrity and packing mode in any cell types examined, and requires just a few cells for its execution (Liman et al., 2011; Yıldız et al., 2009. Chloroform and bromoform are the most important trihalomethanes found in drinking water. Different concentrations of bromoform (25, 50, 75and 100µg/ml and chloroform (25, 50, 100 and 200 µg/ml were introduced to onion tuber roots. Distilled water was used as a negative control and methyl methansulfonate (MMS-10 µg/ml as positive control. All obtained data were subjected to statistical analyses by using SPSS 15.0 for Windows software. For comparison purposes, Duncan multiple range tests using one-way analysis of variance (ANOVA were employed and p<0.05 was accepted as the test of significance. Comet assay results showed that DNA damage was significant at p <0.05 for the different concentrations of chloroform and bromoform compared to the negative control which has a damage rate equal to 3.5 ± 0.7 and the positive control which has damage rate equal to 13.5 ± 2.12. The exposure of root tip cells to these disinfection by-products increases DNA damage. All concentrations examined in this study of bromoform and chloroform cause significant harm, which could be due to DNA damage induced by oxidative stress. The measurement of DNA damage in the nuclei of higher plant tissues is a new area of study with SCGE. This assay could be incorporated into in situ monitoring of atmosphere, water and soil: the comet assay allows a fast detection without 9. The role of phytoplankton as pre-cursors for disinfection by-product formation upon chlorination. Science.gov (United States) Tomlinson, Adam; Drikas, Mary; Brookes, Justin D 2016-10-01 Water quality remains one of the greatest concerns with regards to human health. Advances in science and technology have resulted in highly efficient water treatment plants, significantly reducing diseases related to waterborne pathogenic microorganisms. While disinfection is critical to mitigate pathogen risk to humans, the reactions between the disinfectant and dissolved organic compounds can lead to the formation of chemical contaminants called disinfection by-products (DBPs). DBPs have been related to numerous health issues including birth defects and cancer. The formation of disinfection by-products occurs due to the reaction of oxidants and natural organic matter. DBP precursors are derived from anthropogenic sources including pharmaceuticals and chemical waste, the breakdown of vegetation from external catchment sources (allochthonous) and internally derived sources including phytoplankton (autochthonous). Current literature focuses on the contribution of allochthonous sources towards the formation of DBPs, however, the recalcitrant nature of hydrophilic phytoplankton derived organic matter indicates that autochthonous derived organic carbon can significantly contribute to total DBP concentrations. The contribution of phytoplankton to the formation of DBPs is also influenced by cellular exudation rates, chemical composition, environmental conditions and the physical and chemical conditions of the solution upon disinfection. Formation of DBPs is further influenced by the presence of cyanobacteria phyla due to their notoriety for forming dense blooms. Management of DBP formation can potentially be improved by reducing cyanobacteria as well as DBP precursors derived from other phytoplankton. PMID:27348195 10. Atmospheric oxygenation three billion years ago DEFF Research Database (Denmark) Crowe, Sean; Døssing, Lasse Nørbye; Beukes, Nicolas J.; 2013-01-01 It is widely assumedthat atmospheric oxygen concentrations remained persistently low (less than 1025 timespresent levels) for about the first 2 billion years of Earth’s history1. The first long-term oxygenation of the atmosphere is thought tohave taken place around2.3 billion years ago, during...... the GreatOxidation Event2,3.Geochemical indications of transient atmospheric oxygenation, however, date back to 2.6–2.7 billion years ago4–6. Here we examine the distribution of chromium isotopes and redox-sensitive metals in the approximately 3-billionyear- old Nsuze palaeosol and in the near......-contemporaneous Ijzermyn iron formation fromthe Pongola Supergroup, South Africa.We find extensivemobilization of redox-sensitive elements through oxidative weathering. Furthermore, using our data we compute a best minimumestimate for atmospheric oxygen concentrations at that time of 331024 times present levels... 11. Kinetic and mechanistic studies on the atmospheric oxidation of oxygenated Volatile Organic Compounds: aldehyde, ketones and esters (solvents or car emissions); Etudes des cinetiques et mecanismes de degradation atmospherique de composes organiques volatils oxygenes: aldehydes, cetones et esters (emissions automobiles et solvants) Energy Technology Data Exchange (ETDEWEB) Thevenet, R. 2000-12-01 The atmospheric fate of oxygenated Volatile Organic Compounds (VOCs), used as solvents or emitted by fuel car combustion, is reported in this thesis. Four saturated aldehydes (propanal, isobutyr-aldehyde, pivalaldehyde and valeraldehyde), two unsaturated aldehydes (acrolein and croton-aldehyde), three ketones (2-butanone, 2-methyl-4-pentanone, 2,4-dimethyl-3-pentanone) and three esters (methyl acrylate, methyl methacrylate and methyl pyruvate) have been studied. The rate coefficients of the OH reactions with the VOCs have been measured over the temperature range 233-372 K, using the Pulsed Laser Photolysis - Laser Induced Fluorescence (PLP-LIF) technique. The photo-reactor have been used to measure the reaction rate constants of these VOCs with Cl or O{sub 3} by the relative method. The obtained results are the first determinations for the most of the VOCs. In a second part, the atmospheric oxidation of the VOCs, initiated by OH, have been studied in smog chambers. Analysis have been performed by IRTF and GC-MS. Photo-reactors have been used, a laboratory photo-reactor in Orleans (160 L) and the European Photo-reactor EUPHORE (200 m{sup 3} with sunlight irradiation). The main oxidation pathways of the VOCs and the main products have been identified. For most of the VOCs, there are the first studies. These experimental results leaded to discuss the atmospheric fate of the VOCs in terms of lifetimes and oxidation products of the VOCs. The tropospheric ozone forming potential of the VOCs and their role in the photo-oxidant pollution have been evaluated. (author) 12. Chlorine dioxine DBPs (disinfection by-products in drinking water Directory of Open Access Journals (Sweden) C. Lasagna 2013-01-01 Full Text Available Since the 1970s it has been well known that, though water for human consumption is generally disinfected before being distributed along the network, the use of chemicals results in the formation of many different Disinfection By-Products (DBPs. In the case of chlorine dioxide, the most important and represented DBPs are chlorite and chlorate: after an introduction concerning the current Italian regulation on this subject, in the experimental part the results of a 7-year minitoring campaign, concerning water of different origin collected from taps in various Italian regions, are shown. The analytical technique used for the determination of chlorite and chlorate was Ion Chromatography. The result obtained are finally discussed. 13. Effect of Celebrity Endorsement in Advertising Activities by Product Type Directory of Open Access Journals (Sweden) Karasiewicz Grzegorz 2014-12-01 Full Text Available This article seeks to answer two related questions: are celebrity endorsements more likely to be result in a higher evaluation of the product being advertised than use of an anonymous individual (e.g. a typical consumer; and, if present, do these positive effects vary by product category? To answer these two questions research was conducted on a 237 student sample employing a quasi-experiment consisting of four groups (two product categories and two types of endorsers using data collected through an online survey. The results indicate that celebrity endorsements do have a positive impact on the evaluation of durable goods, but do not affect the evaluation of frequently purchased products. This finding largely confirms the assumptions of the match-up model, the meaning transfer model, and the ELM model. 14. Antioxidant activity, cytotoxic activity and metabolic profiling of juices obtained from saffron (Crocus sativus L.) floral by-products. Science.gov (United States) Tuberoso, Carlo I G; Rosa, Antonella; Montoro, Paola; Fenu, Maurizio Antonio; Pizza, Cosimo 2016-05-15 Juices obtained from cold-pressed saffron (Crocus sativus L.) floral by-products were evaluated as a potential source of compounds with antioxidant and cytotoxic activities. Floral by-products were split in two batches for extraction 24 and 48h after flower harvesting, respectively. The in vitro anti-oxidant activity of these extracts was tested using the FRAP and DPPH assays, and two biological models of lipid oxidation (activity in preventing cholesterol degradation and protection against Cu(2+)-mediated degradation of the liposomal unsaturated fatty acids). The cytotoxic activity was evaluated using the MTT assay. The results show that extracts obtained 48h post-harvest contained higher levels of total polar phenols and had the highest antioxidant activity in all of the performed assays. The LC-DAD and LC-ESI-(HR)MS(n) metabolic profiles showed high levels of kaempferol derivatives and anthocyanins. This study suggests that juices from saffron floral by-products could potentially be used to develop new products for the food and health industry. PMID:26775939 15. Antioxidant activity, cytotoxic activity and metabolic profiling of juices obtained from saffron (Crocus sativus L.) floral by-products. Science.gov (United States) Tuberoso, Carlo I G; Rosa, Antonella; Montoro, Paola; Fenu, Maurizio Antonio; Pizza, Cosimo 2016-05-15 Juices obtained from cold-pressed saffron (Crocus sativus L.) floral by-products were evaluated as a potential source of compounds with antioxidant and cytotoxic activities. Floral by-products were split in two batches for extraction 24 and 48h after flower harvesting, respectively. The in vitro anti-oxidant activity of these extracts was tested using the FRAP and DPPH assays, and two biological models of lipid oxidation (activity in preventing cholesterol degradation and protection against Cu(2+)-mediated degradation of the liposomal unsaturated fatty acids). The cytotoxic activity was evaluated using the MTT assay. The results show that extracts obtained 48h post-harvest contained higher levels of total polar phenols and had the highest antioxidant activity in all of the performed assays. The LC-DAD and LC-ESI-(HR)MS(n) metabolic profiles showed high levels of kaempferol derivatives and anthocyanins. This study suggests that juices from saffron floral by-products could potentially be used to develop new products for the food and health industry. 16. Minimization of the formation of disinfection by-products. Science.gov (United States) Badawy, Mohamed I; Gad-Allah, Tarek A; Ali, Mohamed E M; Yoon, Yeoman 2012-09-01 The drinking water industry is required to minimize DBPs levels while ensuring adequate disinfection. In this study, efficient and appropriate treatment scheme for the reduction of disinfection by-product (DBPs) formation in drinking water containing natural organic matter has been established. This was carried out by the investigation of different treatment schemes consisting of enhanced coagulation, sedimentation, disinfection by using chlorine dioxide/ozone, filtration by sand filter, or granular activated carbon (GAC). Bench scale treatment schemes were applied on actual samples from different selected sites to identify the best conditions for the treatment of water. Samples were collected from effluent of each step in the treatment train in order to analyze pH, UV absorbance at 254 nm (UVA(254)), specific UV absorbance at 254 nm (SUVA(254)), dissolved organic carbon (DOC), haloacetic acids (HAAs) and trihalomethanes (THMs). The obtained results indicated that using pre-ozonation/enhanced coagulation/activated carbon filtration treatment train appears to be the most effective method for reducing DBPs precursors in drinking water treatment. 17. QEMSCAN for characterisation of coal and utilisation by-products Energy Technology Data Exchange (ETDEWEB) David French; Colin Ward; Alan Butcher [University of New South Wales (Australia). CSIRO Energy Technology 2008-05-15 QEMSCAN is an automated electron beam image analysis technique, originally developed by CSIRO, Division of Minerals and now by a CSIRO spin-off company Intellection Pty. Ltd., which has been widely applied in the minerals industry. The objective of this project was to develop new QEMSCAN analytical techniques for coal and coal by-product characterisation that will provide unique phase-specific information that can be used by the coal industry to address technical and marketing issues, to optimise existing utilisation technologies and assist in the development of new technologies. Case studies illustrating how QEMSCAN analysis could be employed were carried out in four areas of coal production and utilisation namely - Coal preparation PF combustion; Boiler deposits; Fly and bottom ash fluidized bed combustion; and Gasification. These case studies have demonstrated that QEMSCAN analysis can provide unique information not readily obtainable by other means. In particular, data can be obtained on particle size and shape, phase identification and abundance, mode of occurrence and association of the identified phases. QEMSCAN analysis can supply information on variations in chemistry of the amorphous phase which is relevant to issues such as ash deposition in pf boilers and ash behaviour in fluidised bed systems. However, it is not an analytical panacea and should always be used in conjunction with other techniques. 18. Health impact of disinfection by-products in swimming pools. Science.gov (United States) Villanueva, Cristina M; Font-Ribera, Laia 2012-01-01 This article is focused on the epidemiological evidence on the health impacts related to disinfection by-products (DBPs) in swimming pools, which is a chemical hazard generated as an undesired consequence to reduce the microbial pathogens. Specific DBPs are carcinogenic, fetotoxic and/or irritant to the airways according to experimental studies. Epidemiological evidence shows that swimming in pools during pregnancy is not associated with an increased risk of reproductive outcomes. An epidemiological study suggested an increased risk of bladder cancer with swimming pool attendance, although evidence is inconclusive. A higher prevalence of respiratory symptoms including asthma is found among swimming pool workers and elite swimmers, although the causality of this association is unclear. The body of evidence in children indicates that asthma is not increased by swimming pool attendance. Overall, the available knowledge suggests that the health benefits of swimming outweigh the potential health risks of chemical contamination. However, the positive effects of swimming should be enhanced by minimising potential risks. PMID:23247135 19. UTILIZATION OF LOW NOx COAL COMBUSTION BY-PRODUCTS Energy Technology Data Exchange (ETDEWEB) J.Y. Hwang; X. Huang; M.G. McKimpson; R.E. Tieder; A.M. Hein; J.M. Gillis; D.C. Popko; K.L. Paxton; Z. Li; X. Liu; X. Song; R.I. Kramer 1998-12-01 Low NO{sub x} combustion practices are critical for reducing NO{sub x} emissions from power plants. These low NO{sub x} combustion practices, however, generate high residual carbon contents in the fly ash produced. These high carbon contents threaten utilization of this combustion by-product. This research has successfully developed a separation technology to render fly ash into useful, quality-controlled materials. This technology offers great flexibility and has been shown to be applicable to all of the fly ashes tested (more than 10). The separated materials can be utilized in traditional fly ash applications, such as cement and concrete, as well as in nontraditional applications such as plastic fillers, metal matrix composites, refractories, and carbon adsorbents. Technologies to use beneficiated fly ash in these applications are being successfully developed. In the future, we will continue to refine the separation and utilization technologies to expand the utilization of fly ash. The disposal of more than 31 million tons of fly ash per year is an important environmental issue. With continued development, it will be possible to increase economic, energy and environmental benefits by re-directing more of this fly ash into useful materials. 20. Health impact of disinfection by-products in swimming pools Directory of Open Access Journals (Sweden) Cristina M. Villanueva 2012-12-01 Full Text Available This article is focused on the epidemiological evidence on the health impacts related to disinfection by-products (DBPs in swimming pools, which is a chemical hazard generated as an undesired consequence to reduce the microbial pathogens. Specific DBPs are carcinogenic, fetotoxic and/or irritant to the airways according to experimental studies. Epidemiological evidence shows that swimming in pools during pregnancy is not associated with an increased risk of reproductive outcomes. An epidemiological study suggested an increased risk of bladder cancer with swimming pool attendance, although evidence is inconclusive. A higher prevalence of respiratory symptoms including asthma is found among swimming pool workers and elite swimmers, although the causality of this association is unclear. The body of evidence in children indicates that asthma is not increased by swimming pool attendance. Overall, the available knowledge suggests that the health benefits of swimming outweigh the potential health risks of chemical contamination. However, the positive effects of swimming should be enhanced by minimising potential risks. 1. Sampling from stochastic reservoir models constrained by production data Energy Technology Data Exchange (ETDEWEB) Hegstad, Bjoern Kaare 1997-12-31 When a petroleum reservoir is evaluated, it is important to forecast future production of oil and gas and to assess forecast uncertainty. This is done by defining a stochastic model for the reservoir characteristics, generating realizations from this model and applying a fluid flow simulator to the realizations. The reservoir characteristics define the geometry of the reservoir, initial saturation, petrophysical properties etc. This thesis discusses how to generate realizations constrained by production data, that is to say, the realizations should reproduce the observed production history of the petroleum reservoir within the uncertainty of these data. The topics discussed are: (1) Theoretical framework, (2) History matching, forecasting and forecasting uncertainty, (3) A three-dimensional test case, (4) Modelling transmissibility multipliers by Markov random fields, (5) Up scaling, (6) The link between model parameters, well observations and production history in a simple test case, (7) Sampling the posterior using optimization in a hierarchical model, (8) A comparison of Rejection Sampling and Metropolis-Hastings algorithm, (9) Stochastic simulation and conditioning by annealing in reservoir description, and (10) Uncertainty assessment in history matching and forecasting. 139 refs., 85 figs., 1 tab. 2. Atmospheric Laboratory for Applications and Science Payload Science.gov (United States) 1994-01-01 This is an STS-66 mission onboard photo of the Space Shuttle Orbiter Atlantis showing the payload of the third Atmospheric Laboratory for Applications and Science (ATLAS-3) mission. During the ATLAS missions, international teams of scientists representing many disciplines combined their expertise to seek answers to complex questions about the atmospheric and solar conditions that sustain life on Earth. The ATLAS program specifically investigated how Earth's middle and upper atmospheres and climate are affected by by the sun and by products of industrial and agricultural activities on Earth. Thirteen ATLAS instruments supported experiments in atmospheric sciences, solar physics, space plasma physics, and astronomy. The instruments were mounted on two Spacelab pallets in the Space Shuttle payload bay. The ATLAS-3 mission continued a variety of atmospheric and solar studies to improve understanding of the Earth's atmosphere and its energy input from the sun. A key scientific objective was to refine existing data on variations in the fragile ozone layer of the atmosphere. The Orbiter Atlantis was launched on November 3, 1994 for the ATLAS-3 mission (STS-66). 3. DEVELOPMENT OF ACTIVATED CARBONS FROM COAL COMBUSTION BY-PRODUCTS Energy Technology Data Exchange (ETDEWEB) Harold H. Schobert; M. Mercedes Maroto-Valer; Zhe Lu 2003-09-30 The increasing role of coal as a source of energy in the 21st century will demand environmental and cost-effective strategies for the use of coal combustion by-products (CCBPs), mainly unburned carbon in fly ash. Unburned carbon is nowadays regarded as a waste product and its fate is mainly disposal, due to the present lack of efficient routes for its utilization. However, unburned carbon is a potential precursor for the production of adsorbent carbons, since it has gone through a devolatilization process while in the combustor, and therefore, only requires to be activated. Accordingly, the principal objective of this work was to characterize and utilize the unburned carbon in fly ash for the production of activated carbons. The unburned carbon samples were collected from different combustion systems, including pulverized utility boilers, a utility cyclone, a stoker, and a fluidized bed combustor. LOI (loss-on-ignition), proximate, ultimate, and petrographic analyses were conducted, and the surface areas of the samples were characterized by N2 adsorption isotherms at 77K. The LOIs of the unburned carbon samples varied between 21.79-84.52%. The proximate analyses showed that all the samples had very low moisture contents (0.17 to 3.39 wt %), while the volatile matter contents varied between 0.45 to 24.82 wt%. The elemental analyses show that all the unburned carbon samples consist mainly of carbon with very little hydrogen, nitrogen, sulfur and oxygen In addition, the potential use of unburned carbon as precursor for activated carbon (AC) was investigated. Activated carbons with specific surface area up to 1075m{sup 2}/g were produced from the unburned carbon. The porosity of the resultant activated carbons was related to the properties of the unburned carbon feedstock and the activation conditions used. It was found that not all the unburned carbon samples are equally suited for activation, and furthermore, their potential as activated carbons precursors could be 4. Photochemical processing of aqueous atmospheric brown carbon Directory of Open Access Journals (Sweden) R. Zhao 2015-01-01 Full Text Available Atmospheric Brown Carbon (BrC is a collective term for light absorbing organic compounds in the atmosphere. While the identification of BrC and its formation mechanisms is currently a central effort in the community, little is known about the atmospheric removal processes of aerosol BrC. As a result, we report a series of laboratory studies of photochemical processing of BrC in the aqueous phase, by direct photolysis and OH oxidation. Solutions of ammonium sulfate mixed with glyoxal (GLYAS or methylglyoxal (MGAS are used as surrogates for a class of secondary BrC mediated by imine intermediates. Three nitrophenol species, namely 4-nitrophenol, 5-nitroguaiacol and 4-nitrocatechol, were investigated as a class of water soluble BrC originating from biomass burning. Photochemical processing induced significant changes in the absorptive properties of BrC. The imine-mediated BrC solutions exhibited rapid photo-bleaching with both direct photolysis and OH oxidation, with atmospheric half-lives of minutes to a few hours. The nitrophenol species exhibited photo-enhancement in the visible range during direct photolysis and the onset of OH oxidation, but rapid photo-bleaching was induced by further OH exposure on an atmospheric timescale of an hour or less. To illustrate atmospheric relevance of this work, we also performed direct photolysis experiments on water soluble organic carbon extracted from biofuel combustion samples and observed rapid changes in optical properties of these samples as well. Overall, these experiments indicate that atmospheric models need to incorporate representations of atmospheric processing of BrC species to accurately model their radiative impacts. 5. Photochemical processing of aqueous atmospheric brown carbon Directory of Open Access Journals (Sweden) R. Zhao 2015-06-01 Full Text Available Atmospheric brown carbon (BrC is a collective term for light absorbing organic compounds in the atmosphere. While the identification of BrC and its formation mechanisms is currently a central effort in the community, little is known about the atmospheric removal processes of aerosol BrC. As a result, we report on a series of laboratory studies of photochemical processing of BrC in the aqueous phase, by direct photolysis and OH oxidation. Solutions of ammonium sulfate mixed with glyoxal (GLYAS or methylglyoxal (MGAS are used as surrogates for a class of secondary BrC mediated by imine intermediates. Three nitrophenol species, namely 4-nitrophenol, 5-nitroguaiacol and 4-nitrocatechol, were investigated as a class of water-soluble BrC originating from biomass burning. Photochemical processing induced significant changes in the absorptive properties of BrC. The imine-mediated BrC solutions exhibited rapid photo-bleaching with both direct photolysis and OH oxidation, with atmospheric half-lives of minutes to a few hours. The nitrophenol species exhibited photo-enhancement in the visible range during direct photolysis and the onset of OH oxidation, but rapid photo-bleaching was induced by further OH exposure on an atmospheric timescale of an hour or less. To illustrate the atmospheric relevance of this work, we also performed direct photolysis experiments on water-soluble organic carbon extracted from biofuel combustion samples and observed rapid changes in the optical properties of these samples as well. Overall, these experiments indicate that atmospheric models need to incorporate representations of atmospheric processing of BrC species to accurately model their radiative impacts. 6. Photochemical processing of aqueous atmospheric brown carbon Science.gov (United States) Zhao, R.; Lee, A. K. Y.; Huang, L.; Li, X.; Yang, F.; Abbatt, J. P. D. 2015-06-01 Atmospheric brown carbon (BrC) is a collective term for light absorbing organic compounds in the atmosphere. While the identification of BrC and its formation mechanisms is currently a central effort in the community, little is known about the atmospheric removal processes of aerosol BrC. As a result, we report on a series of laboratory studies of photochemical processing of BrC in the aqueous phase, by direct photolysis and OH oxidation. Solutions of ammonium sulfate mixed with glyoxal (GLYAS) or methylglyoxal (MGAS) are used as surrogates for a class of secondary BrC mediated by imine intermediates. Three nitrophenol species, namely 4-nitrophenol, 5-nitroguaiacol and 4-nitrocatechol, were investigated as a class of water-soluble BrC originating from biomass burning. Photochemical processing induced significant changes in the absorptive properties of BrC. The imine-mediated BrC solutions exhibited rapid photo-bleaching with both direct photolysis and OH oxidation, with atmospheric half-lives of minutes to a few hours. The nitrophenol species exhibited photo-enhancement in the visible range during direct photolysis and the onset of OH oxidation, but rapid photo-bleaching was induced by further OH exposure on an atmospheric timescale of an hour or less. To illustrate the atmospheric relevance of this work, we also performed direct photolysis experiments on water-soluble organic carbon extracted from biofuel combustion samples and observed rapid changes in the optical properties of these samples as well. Overall, these experiments indicate that atmospheric models need to incorporate representations of atmospheric processing of BrC species to accurately model their radiative impacts. 7. Overview of Disinfection By-products and Associated Health Effects. Science.gov (United States) Villanueva, Cristina M; Cordier, Sylvaine; Font-Ribera, Laia; Salas, Lucas A; Levallois, Patrick 2015-03-01 The presence of chemical compounds formed as disinfection by-products (DBPs) is widespread in developed countries, and virtually whole populations are exposed to these chemicals through ingestion, inhalation, or dermal absorption from drinking water and swimming pools. Epidemiological evidence has shown a consistent association between long-term exposure to trihalomethanes and the risk of bladder cancer, although the causal nature of the association is not conclusive. Evidence concerning other cancer sites is insufficient or mixed. Numerous studies have evaluated reproductive implications, including sperm quality, time to pregnancy, menstrual cycle, and pregnancy outcomes such as fetal loss, fetal growth, preterm delivery, and congenital malformation. The body of evidence suggests only minor effects from high exposure during pregnancy on fetal growth indices such as small for gestational age (SGA) at birth. Populations highly exposed to swimming pools such as pool workers and professional swimmers show a higher prevalence of respiratory symptoms and asthma, respectively, although the direction of the association, and thus causality, is not clear among professional swimmers. The risk of asthma, wheezing, eczema, and other respiratory outcomes among children attending swimming pools has been the object of extensive research. Early studies suggested a positive association, while subsequent larger studies found no correlations or showed a protective association. Future research should develop methods to evaluate the effects of the DBP mixture and the interaction with personal characteristics (e.g., genetics, lifestyle), clarify the association between swimming pools and respiratory health, evaluate the occurrence of DBPs in low- and middle-income countries, and evaluate outcomes suggested by animal studies that have not been considered in epidemiological investigations. PMID:26231245 8. Atmospheric degradation mechanism of organic sulfur compounds Energy Technology Data Exchange (ETDEWEB) Benter, T.; Arsene, C. 2002-02-01 In the present work a detailed product study has been performed on the OH radical initiated oxidation of dimethyl sulphide and dimethyl sulphoxide, under different conditions of temperature, partial pressure of oxygen and NO{sub x} concentration, in order to better define the degradation mechanism of the above compounds under conditions which prevail in the atmosphere. (orig.) 9. Atmospheric oxygenation three billion years ago. Science.gov (United States) Crowe, Sean A; Døssing, Lasse N; Beukes, Nicolas J; Bau, Michael; Kruger, Stephanus J; Frei, Robert; Canfield, Donald E 2013-09-26 It is widely assumed that atmospheric oxygen concentrations remained persistently low (less than 10(-5) times present levels) for about the first 2 billion years of Earth's history. The first long-term oxygenation of the atmosphere is thought to have taken place around 2.3 billion years ago, during the Great Oxidation Event. Geochemical indications of transient atmospheric oxygenation, however, date back to 2.6-2.7 billion years ago. Here we examine the distribution of chromium isotopes and redox-sensitive metals in the approximately 3-billion-year-old Nsuze palaeosol and in the near-contemporaneous Ijzermyn iron formation from the Pongola Supergroup, South Africa. We find extensive mobilization of redox-sensitive elements through oxidative weathering. Furthermore, using our data we compute a best minimum estimate for atmospheric oxygen concentrations at that time of 3 × 10(-4) times present levels. Overall, our findings suggest that there were appreciable levels of atmospheric oxygen about 3 billion years ago, more than 600 million years before the Great Oxidation Event and some 300-400 million years earlier than previous indications for Earth surface oxygenation. 10. Coal slurry solids/coal fluidized bed combustion by-product mixtures as plant growth media Science.gov (United States) Darmody, R.G.; Green, W.P.; Dreher, G.B. 1998-01-01 Fine-textured, pyritic waste produced by coal cleaning is stored in slurry settling ponds that eventually require reclamation. Conventionally, reclamation involves covering the dewatered coal slurry solids (CSS) with 1.3 m of soil to allow plant growth and prevent acid generation by pyrite oxidation. This study was conducted to determine the feasiblity of a less costly reclamation approach that would eliminate the soil cover and allow direct seeding of plants into amended CSS materials. Potential acidity of the CSS would be neutralized by additions of fluidized-bed combustion by-product (FBCB), an alkaline by-product of coal combustion. The experiment involved two sources of CSS and FBCB materials from Illinois. Birdsfoot trefoil (Lotus corniculatus L.), tall fescue (Festuca arundinacea Schreb.), and sweet clover (Melilotus officinalis (L.) Lam.) were seeded in the greenhouse into pots containing mixtures of the materials. CSS-1 had a high CaCO3:FeS2 ratio and needed no FBCB added to compensate for its potential acidity. CSS-2 was mixed with the FBCB materials to neutralize potential acidity (labeled Mix A and B). Initial pH was 5.6, 8.8, and 9.2 for the CSS-1, Mix A, and Mix B materials, respectively. At the end of the 70-day experiment, pH was 5.9 for all mixtures. Tall fescue and sweet clover grew well in all the treatments, but birdsfoot trefoil had poor emergence and survival. Elevated tissue levels of B, Cd, and Se were found in some plants. Salinity, low moisture holding capacity, and potentially phytotoxic B may limit the efficacy of this reclamation method. 11. Production, modification, and consumption of atmospheric trace gases by microorganisms OpenAIRE Schlegel, Prof. Dr. H. G. 2011-01-01 Some trace gases are contained in the atmosphere in appreciable amounts: methane, carbon monoxide, hydrogen, nitrous oxide. The bulk of these gases is of biological origin. Hydrogen is a primary product of microbial metabolism under anaerobic conditions. However, before reaching the atmosphere, it is converted by methane bacteria to methane, by nitrate reducing bacteria to nitrogen and to nitrous oxide and by sulfate reducing bacteria to hydrogen sulfide. Carbon monoxide is produced from cert... 12. Atmospheric composition change: Ecosystems-Atmosphere interactions NARCIS (Netherlands) Fowler, D.; Pilegaard, K.; Sutton, M.A.; Ambus, P.; Raivonen, M.; Duyzer, J.; Simpson, D.; Fagerli, H.; Fuzzi, S.; Schjoerring, J.K.; Granier, C.; Neftel, A.; Isaksen, I.S.A.; Laj, P.; Maione, M.; Monks, P.S.; Burkhardt, J.; Daemmgen, U.; Neirynck, J.; Personne, E.; Wichink Kruit, R.J.; Butterbach-Bahl, K.; Flechard, C.; Tuovinen, J.P.; Coyle, M.; Gerosa, G.; Loubet, B.; Altimir, N.; Gruenhage, L.; Ammann, C.; Cieslik, S.; Paoletti, E.; Mikkelsen, T.N.; Ro-Poulsen, H.; Cellier, P.; Cape, J.N.; Horvath, L.; Loreto, F.; Niinemets, U.; Palmer, P.I.; Rinne, J.; Misztal, P.; Nemitz, E.; Nilsson, D.; Pryor, S.; Gallagher, M.W.; Vesala, T.; Skiba, U.; Brueggemann, N.; Zechmeister-Boltenstern, S.; Williams, J.; O'Dowd, C.; Facchini, M.C.; Leeuw, de G.; Flossman, A.; Chaumerliac, N.; Erisman, J.W. 2009-01-01 Ecosystems and the atmosphere: This review describes the state of understanding the processes involved in the exchange of trace gases and aerosols between the earth's surface and the atmosphere. The gases covered include NO, NO2, HONO, HNO3, NH3, SO2, DMS, Biogenic VOC, O-3, CH4, N2O and particles i 13. The evolution of the prebiotic atmosphere Science.gov (United States) Kasting, J. F. 1984-01-01 One-dimensional radiative-convective and photochemical models are used to estimate the vertical temperature structure and composition of the earth's prebiotic atmosphere. Greatly enhanced CO2 levels (100-1000 times present) are required to keep the mean surface temperature above freezing in the face of decreased solar luminosity during the earth's early history. Such high CO2 partial pressures would have affected the atmospheric oxidation state by facilitating the photochemical production of soluble species including H2O2 and H2CO. Oxidation of ferrous iron in the oceans by H2O2 dissolved in rainwater should have kept the atmospheric H2 mixing ratio above 0.0002, and the ground-level O2 mixing ratio below 10 to the -11th, regardless of the magnitude of the rate of volcanic release of reduced gases. 14. Concentration of tritium in the atmosphere International Nuclear Information System (INIS) Concentration of tritium in the atmosphere was measured in Ibaraki, Japan. At first, sampled air was passed through a column of molecular sieve, and all the water vapour was removed. Hydrogen gas obtained by the electrolysis of water was added to the air, and oxidized by a Pd catalyst column, then the oxidized hydrogen was absorbed by a last column of molecular sieves. These columns of molecular sieves were dehydrated by heating at 400 deg C. The concentration range of atmospheric HTO and HT was 1-2 pCi/m3 in Ibaraki for a year. The concentration of atmospheric HTO varied depending on the content of water vapour in air. (J.P.N.) 15. The global atmospheric budget of ethanol revisited Directory of Open Access Journals (Sweden) W. V. Kirstine 2012-01-01 Full Text Available Ethanol is an important biogenic volatile organic compound, which is increasingly used as a fuel for motor vehicles; therefore, an improved understanding of its atmospheric cycle is important. In this paper we use three sets of observational data, measured emissions of ethanol from living plants, measured concentrations of ethanol in the atmosphere and measured hydroxyl concentrations in the atmosphere (by methyl chloroform titration, to make two independent estimates related to the rate of cycling of ethanol through the atmosphere. In the first estimate, simple calculations give the emission rate of ethanol from living plants as 26 (range, 10–38 Tg yr−1. This contributes significantly to the total global ethanol source of 42 (range, 25–56 Tg yr−1. In the second estimate, the total losses of ethanol from the global atmosphere are 70 (range, 50–90 Tg yr−1, with about three-quarters of the ethanol removed by reaction with hydroxyl radicals in the gaseous and aqueous phases of the atmosphere, and the remainder lost through wet and dry deposition to land. These values of both the source of ethanol from living plants and the removal of atmospheric ethanol via oxidation by hydroxyl radicals (derived entirely from observations are significantly larger than those in recent literature. We suggest that a revision of the estimate of global ethanol emissions from plants to the atmosphere to a value comparable with this analysis is warranted. 16. Identification of ozonation by-products of 4- and 5-methyl-1H-benzotriazole during the treatment of surface water to drinking water. Science.gov (United States) Müller, Alexander; Weiss, Stefan C; Beisswenger, Judith; Leukhardt, H Georg; Schulz, Wolfgang; Seitz, Wolfram; Ruck, Wolfgang K L; Weber, Walter H 2012-03-01 During the treatment of surface water to drinking water, ozonation is often used for disinfection and to remove organic trace substances, whereby oxidation by-products can be formed. Here we use the example of tolyltriazole to describe an approach for identifying relevant oxidation by-products in the laboratory and subsequently detecting them in an industrial-scale process. The identification process involves ozonation experiments with pure substances at laboratory level (concentration range mg L(-1)). The reaction solutions from different ozone contact times were analyzed by high performance liquid chromatography - quadrupole time-of-flight mass spectrometry (HPLC-QTOF-MS) in full scan mode. Various approaches were used to detect the oxidation by-products: (i) target searches of postulated oxidation by-products, (ii) comparisons of chromatograms (e.g., UV/VIS) of the different samples, and (iii) color-coded abundance time courses (kinetic) of all detected compounds were illustrated in a kind of a heat map. MS/MS, H/D exchange, and derivatization experiments were used for structure elucidation for the detected by-product. Due to the low contaminant concentrations (ng L(-1)-range) of contaminants in the untreated water, the conversion of results from laboratory experiments to an industrial-scale required the use of HPLC-MS/MS with sample enrichment (e.g., solid phase extraction.) In cases where reference substances were not available or oxidation by-products without clear structures were detected, reaction solutions from laboratory experiments were used to optimize the analytical method to detect ng L(-1) in the samples of the industrial processes. We exemplarily demonstrated the effectiveness of the methodology with the industrial chemicals 4- and 5-methyl-1H-benzotriazole (4- and 5-MBT) as an example. Moreover, not only did we identify several oxidation by-products in the laboratory experiments tentatively, but also detected three of the eleven reaction 17. Growth of ˜5 cm2V-1s-1 mobility, p-type Copper(I) oxide (Cu2O) films by fast atmospheric atomic layer deposition (AALD) at 225°C and below Science.gov (United States) Muñoz-Rojas, D.; Jordan, M.; Yeoh, C.; Marin, A. T.; Kursumovic, A.; Dunlop, L. A.; Iza, D. C.; Chen, A.; Wang, H.; MacManus Driscoll, J. L. 2012-12-01 Phase pure, dense Cu2O thin films were grown on glass and polymer substrates at 225°C by rapid atmospheric atomic layer deposition (AALD). Carrier mobilities of 5 cm2V-1s-1 and carrier concentrations of ˜1016 cm-3 were achieved in films of thickness 50 - 120 nm, over a >10 cm2 area. Growth rates were ˜1 nm.min-1 which is two orders of magnitude faster than conventional ALD.. The high mobilities achieved using the atmospheric, low temperature method represent a significant advance for flextronics and flexible solar cells which require growth on plastic substrates. 18. Growth of ∼5 cm2V−1s−1 mobility, p-type Copper(I oxide (Cu2O films by fast atmospheric atomic layer deposition (AALD at 225°C and below Directory of Open Access Journals (Sweden) D. Muñoz-Rojas 2012-12-01 Full Text Available Phase pure, dense Cu2O thin films were grown on glass and polymer substrates at 225°C by rapid atmospheric atomic layer deposition (AALD. Carrier mobilities of 5 cm2V−1s−1 and carrier concentrations of ∼1016 cm−3 were achieved in films of thickness 50 - 120 nm, over a >10 cm2 area. Growth rates were ∼1 nm·min−1 which is two orders of magnitude faster than conventional ALD.. The high mobilities achieved using the atmospheric, low temperature method represent a significant advance for flextronics and flexible solar cells which require growth on plastic substrates. 19. Atmosphere purification of radon and radon daughter elements Science.gov (United States) Stein, L. 1974-01-01 A method of removing radon and radon daughter elements from an atmosphere containing these elements by passing the atmosphere through a bed of fluorinating compound whereby the radon and radon daughters are oxidized to their respective fluorides is discussed. These fluorides adhere to the fluorinating compound and are thus removed from the atmosphere which may then be recirculated. A method for recovering radon and separating radon from its daughter elements is also described. (Official Gazette) 20. Bioanalytical and chemical evaluation of disinfection by-products in swimming pool water. Science.gov (United States) Yeh, Ruby Y L; Farré, Maria José; Stalter, Daniel; Tang, Janet Y M; Molendijk, Jeffrey; Escher, Beate I 2014-08-01 Pool water disinfection is vital to prevent microbial pathogens. However, potentially hazardous disinfection by-products (DBP) are formed from the reaction between disinfectants and organic/inorganic precursors. The aim of this study was to evaluate the presence of DBPs in various swimming pool types in Brisbane, Australia, including outdoor, indoor and baby pools, and the dynamics after a complete water renewal. Chemical analysis of 36 regulated and commonly found DBPs and total adsorbable organic halogens as well as in vitro bioassays targeting cytotoxicity, oxidative stress and genotoxicity were used to evaluate swimming pool water quality. Dichloroacetic acid and trichloroacetic acid dominated in the pool water samples with higher levels (up to 2600 μg/L) than the health guideline values set by the Australian Drinking Water Guidelines (100 μg/L). Chlorinated DBPs occurred at higher concentrations compared to tap water, while brominated DBPs decreased gradually with increasing pool water age. Biological effects were expressed as chloroacetic acid equivalent concentrations and compared to predicted effects from chemical analysis and biological characterisation of haloacetic acids. The quantified haloacetic acids explained 35-118% of the absorbable organic halogens but less than 4% of the observed non-specific toxicity (cytotoxicity), and less than 1% of the observed oxidative stress response and genotoxicity. While the DBP concentrations in Australian pools found in this study are not likely to cause any adverse health effect, they are higher than in other countries and could be reduced by better hygiene of pool users, such as thorough showering prior to entering the pool and avoiding urination during swimming. 1. HPLC-UV ATMOSPHERIC-PRESSURE IONIZATION MASS-SPECTROMETRIC DETERMINATION OF THE DOPAMINE-D2 AGONIST N-0923 AND ITS MAJOR METABOLITES AFTER OXIDATIVE-METABOLISM BY RAT-LIVER, MONKEY LIVER, AND HUMAN LIVER-MICROSOMES NARCIS (Netherlands) SWART, PJ; BRONNER, GM; BRUINS, AP; ENSING, K; TEPPER, PG; DEZEEUW, RA 1993-01-01 An innovative custom-built atmospheric ionization source afforded an opportunity to perform on-line LC/MS analysis and to obtain identification of metabolites without need to rely on radioactive profiling. An HPLC with a UV detector coupled to a modified R 3010 triple quadrupole mass spectrometer wa 2. Oxidative stability of fatty acid alkyl esters: a review. Directory of Open Access Journals (Sweden) Michal Angelovič 2015-12-01 performance. Biodiesels are more susceptible to degradation compared to fossil diesel because of the presence of unsaturated fatty acid chain in it. The mechanisms of oxidative degradation are autoxidation in presence of atmospheric oxygen; thermal or thermal-oxidative degradation from excess heat; hydrolysis in presence of moisture or water during storage and in fuel lines; and microbial contamination from contact with dust particles or water droplets containing fungi or bacteria into the fuel. The oxidation of lipids is a complex process in which unsaturated fatty acids are reacted with molecular oxygen by means of free radicals. The radicals react with lipids, and cause oxidative destruction of unsaturated, polyunsaturated fatty acids, therefore, known as lipid peroxidation. The factors such as heat, oxygen, light, and some metal ions, especially iron and copper, also play a significant role in creating oxidation. Oxidative products formed in biodiesel affect fuel storage life, contribute to deposit formation in tanks, and they may cause clogging of fuel filters and injection systems. The volatile organic acids formed as secondary by products of the oxidative degradation, may stimulate corrosion in the fuel system. Poor stability can lead to increasing acid numbers, increasing fuel viscosity, and the formation of gums and sediments. In general, antioxidants can prevent oxidation. Biodiesel, because it contains large numbers of molecules with double bonds, is much less oxidatively stable than petroleum-based diesel fuel. Oxidation stability is the important parameter to determine the storage of biodiesel for longer period of time. Biodiesel samples were evaluated according to methods on the base of kept in contact with pure oxygen at elevated temperatures and pressures. The results show that the performance antioxidants variation is observed for biodiesel. The most commonly used primary synthetic antioxidants 3. Statistics in Atmospheric Science OpenAIRE Solow, Andrew R. 2003-01-01 This paper reviews the use of statistical methods in atmospheric science. The applications covered include the development, assessment and use of numerical physical models of the atmosphere and more empirical analysis unconnected to physical models. 4. Planetary Atmospheric Electricity CERN Document Server Leblanc, F; Yair, Y; Harrison, R. G; Lebreton, J. P; Blanc, M 2008-01-01 This volume presents our contemporary understanding of atmospheric electricity at Earth and in other solar system atmospheres. It is written by experts in terrestrial atmospheric electricity and planetary scientists. Many of the key issues related to planetary atmospheric electricity are discussed. The physics presented in this book includes ionisation processes in planetary atmospheres, charge generation and separation, and a discussion of electromagnetic signatures of atmospheric discharges. The measurement of thunderstorms and lightning, including its effects and hazards, is highlighted by articles on ground and space based instrumentation, and new missions.Theory and modelling of planetary atmospheric electricity complete this review of the research that is undertaken in this exciting field of space science. This book is an essential research tool for space scientists and geoscientists interested in electrical effects in atmospheres and planetary systems. Graduate students and researchers who are new to t... 5. Atmospheric Lepton Fluxes CERN Document Server Gaisser, Thomas K 2014-01-01 This review of atmospheric muons and neutrinos emphasizes the high energy range relevant for backgrounds to high-energy neutrinos of astrophysical origin. After a brief historical introduction, the main distinguishing features of atmospheric$\ Data.gov (United States) National Aeronautics and Space Administration — Earth Science data access made simple. Atmospheric Composition is focused on the composition of Earth's atmosphere in relation to climate prediction, solar effects,... 7. Our shared atmosphere Science.gov (United States) Our atmosphere is a precious and fascinating resource, providing air to breath, shielding us from harmful ultraviolet radiation (UV), and maintaining a comfortable climate. Since the industrial revolution, people have significantly altered the composition of the atmosphere throu... 8. Evolution of Oxidative Continental Weathering Science.gov (United States) Konhauser, Kurt; Lalonde, Stefan 2014-05-01 The Great Oxidation Event (GOE) is currently viewed as a protracted process during which atmospheric oxygen levels increased above 10-5 times the present atmospheric level. This value is based on the loss of sulphur isotope mass independent fractionation (S-MIF) from the rock record, beginning at 2.45 Ga and disappearing by 2.32 Ga. However, a number of recent papers have pushed back the timing for oxidative continental weathering, and by extension, the onset of atmospheric oxygenation several hundreds of million years earlier despite the presence of S-MIF (e.g., Crowe et al., 2013). This apparent discrepancy can, in part, be resolved by the suggestion that recycling of older sedimentary sulphur bearing S-MIF might have led to this signal's persistence in the rock record for some time after atmospheric oxygenation (Reinhard et al., 2013). Here we suggest another possibility, that the earliest oxidative weathering reactions occurred in environments at profound redox disequilibrium with the atmosphere, such as biological soil crusts, riverbed and estuarine sediments, and lacustrine microbial mats. We calculate that the rate of O2 production via oxygenic photosynthesis in these terrestrial microbial ecosystems provides largely sufficient oxidizing potential to mobilise sulphate and a number of redox-sensitive trace metals from land to the oceans while the atmosphere itself remained anoxic with its attendant S-MIF signature. These findings reconcile geochemical signatures in the rock record for the earliest oxidative continental weathering with the history of atmospheric sulphur chemistry, and demonstrate the plausible antiquity of a terrestrial biosphere populated by cyanobacteria. Crowe, S.A., Dossing, L.N., Beukes, N.J., Bau, M., Kruger, S.J., Frei, R. & Canfield, D.E. Atmospheric oxygenation three billion years ago. Nature 501, 535-539 (2013). Reinhard, C.T., Planavsky, N.J. & Lyons, T.W. Long-term sedimentary recycling of rare sulphur isotope anomalies. Nature 497 9. Mars Molniya Orbit Atmospheric Resource Mining Science.gov (United States) Mueller, Robert P.; Braun, Robert D.; Sibille, Laurent; Sforzo, Brandon; Gonyea, Keir; Ali, Hisham 2016-01-01 This NIAC (NASA Advanced Innovative Concepts) work will focus on Mars and will build on previous efforts at analyzing atmospheric mining at Earth and the outer solar system. Spacecraft systems concepts will be evaluated and traded, to assess feasibility. However the study will primarily examine the architecture and associated missions to explore the closure, constraints and critical parameters through sensitivity studies. The Mars atmosphere consists of 95.5 percent CO2 gas which can be converted to methane fuel (CH4) and Oxidizer (O2) for chemical rocket propulsion, if hydrogen is transported from electrolyzed water on the Mars surface or from Earth. By using a highly elliptical Mars Molniya style orbit, the CO2 atmosphere can be scooped, ram-compressed and stored while the spacecraft dips into the Mars atmosphere at periapsis. Successive orbits result in additional scooping of CO2 gas, which also serves to aerobrake the spacecraft, resulting in a decaying Molniya orbit. 10. Catalysts development to base of Cu and Ni supported in ZrO{sub 2} for the H{sub 2} generation by the methanol reformed in oxidizing atmosphere;Desarrollo de catalizadores a base de Cu y Ni soportados en ZrO{sub 2} para la generacion de H{sub 2} mediante el reformado de metanol en atmosfera oxidante Energy Technology Data Exchange (ETDEWEB) Lopez C, P.; Gutierrez, A.; Gutierrez W, C.; Mendoza A, D.; Martinez, G.; Perez H, R., E-mail: raul.perez@inin.gob.m [ININ, Departamento de Tecnologia de Materiales, Carretera Mexico-Toluca s/n, Ocoyoacac 52750, Estado de Mexico (Mexico) 2009-07-01 The search of new alternating sources of energy is at the present time one of the primordial objectives to world level because of the global heating caused by the high emissions of CO{sub 2} at the atmosphere. In this sense the employment of H{sub 2} through the fuel cells offers a more viable alternative for the use of the energy coming from the connection H-H that can be appointed for use of mobile, industrial and homemade applications. However, to generate H{sub 2} in enough quantities is a great challenge at technological level for the necessity of to count with highly selective and efficient catalysts to low reaction temperatures as well as a source that comes from renewable resources. Under this context the methanol reformed in oxidizing atmosphere offers great ecological as energetics and industrial advantages; inside this investigation plane, the Cu seems to be one of the suitable candidates for this reaction due to its high capacity to generate H{sub 2}, besides the great potential of improvement in its physical-chemical properties when being worked in nano metric size and /or associated with other materials. On the other hand, it is known that the Ni addition improvement the catalytic properties because of a better material dispersion, what offers big possibilities of being applied in the H{sub 2} generation in situ by means of the methanol reformed reaction in oxidizing atmosphere; and that the conformation of bimetallic particles Cu/Ni presented high selectivity and catalytic activity for the reaction in question. (Author) 11. Roadmap for Interdisciplinary Research on Drinking Water Disinfection By-Products Science.gov (United States) Slide presentation on interdisciplinary research on drinking water disinfection by-products which summarized important issues with drinking water disinfection by-products and focused on emerging, unregulated DBPs. 12. Atmospheric refraction : a history NARCIS (Netherlands) Lehn, WH; van der Werf, S 2005-01-01 We trace the history of atmospheric refraction from the ancient Greeks up to the time of Kepler. The concept that the atmosphere could refract light entered Western science in the second century B.C. Ptolemy, 300 years later, produced the first clearly defined atmospheric model, containing air of un 13. The epidemiology and possible mechanisms of disinfection by-products in drinking water. Science.gov (United States) Nieuwenhuijsen, Mark J; Grellier, James; Smith, Rachel; Iszatt, Nina; Bennett, James; Best, Nicky; Toledano, Mireille 2009-10-13 This paper summarizes the epidemiological evidence for adverse health effects associated with disinfection by-products (DBPs) in drinking water and describes the potential mechanism of action. There appears to be good epidemiological evidence for a relationship between exposure to DBPs, as measured by trihalomethanes (THMs), in drinking water and bladder cancer, but the evidence for other cancers including colorectal cancer is inconclusive and inconsistent. There appears to be some evidence for an association between exposure to DBPs, specifically THMs, and little for gestational age/intrauterine growth retardation and, to a lesser extent, pre-term delivery, but evidence for relationships with other outcomes such as low birth weight, stillbirth, congenital anomalies and semen quality is inconclusive and inconsistent. Major limitations in exposure assessment, small sample sizes and potential biases may account for the inconclusive and inconsistent results in epidemiological studies. Moreover, most studies have focused on total THMs as the exposure metric, whereas other DBPs appear to be more toxic than the THMs, albeit generally occurring at lower levels in the water. The mechanisms through which DBPs may cause adverse health effects including cancer and adverse reproductive effects have not been well investigated. Several mechanisms have been suggested, including genotoxicity, oxidative stress, disruption of folate metabolism, disruption of the synthesis and/or secretion of placental syncytiotrophoblast-derived chorionic gonadotropin and lowering of testosterone levels, but further work is required in this area. 14. Novel technological strategies to enhance tropical thiol precursors in winemaking by-products. Science.gov (United States) Román Villegas, Tomás; Tonidandel, Loris; Fedrizzi, Bruno; Larcher, Roberto; Nicolini, Giorgio 2016-09-15 Grape pomace is a winemaking by-product that can be used to extract oenological tannins. Recently, some grape skin tannins were shown to contain very high amounts of two polyfunctional thiol precursors (3-S-glutathionylhexan-1-ol, 3-S-cysteinylhexan-1-ol) whose free forms are responsible for appreciated tropical-like flavours. This study shows that an oxidative treatment (no SO2) of white grape pomace and the presence of grape leaves and stems can increase the content of the above mentioned precursors. Moreover, it shows significant differences between Sauvignon Blanc, Gewuerztraminer and Mueller-Thurgau grape pomace for the 3-mercaptohexan-1-ol precursors and 4-S-cysteinyl-4-methylpentan-2-one. The grape cultivar is crucial, but the technological ability of enhancing the level of the volatile thiol precursors simply by treating the grape marc in different ways is a promising and powerful tool for the production of potentially flavouring tannins intended for food and beverage industry. PMID:27080874 15. In situ detection of lipid peroxidation by-products in chronic liver diseases. Science.gov (United States) Paradis, V; Kollinger, M; Fabre, M; Holstege, A; Poynard, T; Bedossa, P 1997-07-01 Lipid peroxidation is an autocatalytic mechanism leading to oxidative destruction of cellular membranes. The deleterious consequences of this mechanism are related in part to the formation of reactive aldehydic products that bind to intra- or extracellular molecules to form adducts. Specific antibodies directed against malondialdehyde (MDA) and 4-hydroxynonenal (HNE) adducts, major aldehydic metabolites of lipid peroxidation, allowed us to investigate in situ, with an immunohistochemical procedure, the occurrence of lipid peroxidation in a panel of different chronic liver diseases. Intracellular HNE and MDA adducts were detected respectively in 24 of 39 cases (62%) and in 12 of 34 cases investigated (35%). They were localized mainly in the cytoplasm of hepatocytes, with the strongest staining observed in hemochromatosis, Wilson's disease, and in areas of acute alcoholic hepatitis in cases of alcoholic liver diseases. A peculiar pattern of immunostaining was observed in primary biliary cirrhosis where biliary cells of destroyed but also intact bile ducts strongly expressed HNE adducts. The liver extracellular matrix also displayed MDA adducts (30 of 34 cases, 88%) and HNE adducts (23 of 39 cases, 59%). While HNE adducts were specifically localized on large bundles of collagen fibers, MDA adducts were detected in a thin reticular network and in sinusoidal cells around portal tracts or fibrous septa. In conclusion, lipid peroxidation by-products are detectable in chronic liver diseases. Immunohistochemical results suggest that this mechanism is implicated very early in the pathogenesis of some of these diseases. 16. Nonisothermal Pluto atmosphere models International Nuclear Information System (INIS) The present thermal profile calculation for a Pluto atmosphere model characterized by a high number fraction of CH4 molecules encompasses atmospheric heating by solar UV flux absorption and conductive transport cooling to the surface of Pluto. The stellar occultation curve predicted for an atmosphere of several-microbar surface pressures (which entail the existence of a substantial temperature gradient close to the surface) agrees with observations and implies that the normal and tangential optical depth of the atmosphere is almost negligible. The minimum period for atmospheric methane depletion is calculated to be 30 years. 29 refs 17. Autotrophic ammonia oxidation by soil thaumarchaea OpenAIRE Zhang, Li-Mei; Offre, Pierre R.; He, Ji-Zheng; Verhamme, Daniel T.; Nicol, Graeme W.; Prosser, James I. 2010-01-01 Nitrification plays a central role in the global nitrogen cycle and is responsible for significant losses of nitrogen fertilizer, atmospheric pollution by the greenhouse gas nitrous oxide, and nitrate pollution of groundwaters. Ammonia oxidation, the first step in nitrification, was thought to be performed by autotrophic bacteria until the recent discovery of archaeal ammonia oxidizers. Autotrophic archaeal ammonia oxidizers have been cultivated from marine and thermal spring environments, bu... 18. Alternative pathway for atmospheric particles growth. Science.gov (United States) Monge, Maria Eugenia; Rosenørn, Thomas; Favez, Olivier; Müller, Markus; Adler, Gabriela; Abo Riziq, Ali; Rudich, Yinon; Herrmann, Hartmut; George, Christian; D'Anna, Barbara 2012-05-01 Credible climate change predictions require reliable fundamental scientific knowledge of the underlying processes. Despite extensive observational data accumulated to date, atmospheric aerosols still pose key uncertainties in the understanding of Earth's radiative balance due to direct interaction with radiation and because they modify clouds' properties. Specifically, major gaps exist in the understanding of the physicochemical pathways that lead to aerosol growth in the atmosphere and to changes in their properties while in the atmosphere. Traditionally, the driving forces for particle growth are attributed to condensation of low vapor pressure species following atmospheric oxidation of volatile compounds by gaseous oxidants. The current study presents experimental evidence of an unaccounted-for new photoinduced pathway for particle growth. We show that heterogeneous reactions activated by light can lead to fast uptake of noncondensable Volatile Organic Compounds (VOCs) at the surface of particles when only traces of a photosensitizer are present in the seed aerosol. Under such conditions, size and mass increase; changes in the chemical composition of the aerosol are also observed upon exposure to volatile organic compounds such as terpenes and near-UV irradiation. Experimentally determined growth rate values match field observations, suggesting that this photochemical process can provide a new, unaccounted-for pathway for atmospheric particle growth and should be considered by models. 19. Chemistry of Planetary Atmospheres: Insights and Prospects Science.gov (United States) Yung, Yuk 2015-11-01 Using observations from the Mariners, Pioneers, Vikings, Voyagers, Pioneer Venus, Galileo, Venus Express, Curiosity, Cassini, New Horizons, and numerous observatories both in orbit of Earth and on the ground, I will give a survey of the major chemical processes that control the composition of planetary atmospheres. For the first time since the beginning of the space age, we understand the chemistry of planetary atmospheres ranging from the primitive atmospheres of the giant planets to the highly evolved atmospheres of terrestrial planets and small bodies. Our understanding can be distilled into three important ideas: (1) The stability of planetary atmospheres against escape of their constituents to space, (2) the role of equilibrium chemistry in determining the partitioning of chemical species, and (3) the role of disequilibrium chemistry, which produces drastic departures from equilibrium chemistry. To these three ideas we must also add a fourth: the role of biochemistry at Earth's surface, which makes its atmospheric chemistry unique in the cosmochemical environment. Only in the Earth's atmosphere do strong reducing and oxidizing species coexist to such a degree. For example, nitrogen species in the Earth's atmosphere span eight oxidation states from ammonia to nitric acid. Much of the Earth's atmospheric chemistry consists of reactions initiated by the degradation of biologically produced molecules. Life uses solar energy to drive chemical reactions that would otherwise not occur; it represents a kind of photochemistry that is special to Earth, at least within the Solar System. It remains to be seen how many worlds like Earth there are beyond the Solar System, especially as we are now exploring the exoplanets using Kepler, TESS, HST, Spitzer, soon to be launched missions such as JWST and WFIRST, and ground-based telescopes. The atmospheres of the Solar System provide a benchmark for studying exoplanets, which in turn serve to test and extend our current 20. Fluctuations in Precambrian atmospheric oxygenation recorded by chromium isotopes Science.gov (United States) Frei, Robert; Gaucher, Claudio; Poulton, Simon W.; Canfield, Don E. 2009-09-01 Geochemical data suggest that oxygenation of the Earth's atmosphere occurred in two broad steps. The first rise in atmospheric oxygen is thought to have occurred between ~2.45 and 2.2Gyr ago, leading to a significant increase in atmospheric oxygen concentrations and concomitant oxygenation of the shallow surface ocean. The second increase in atmospheric oxygen appears to have taken place in distinct stages during the late Neoproterozoic era (~800-542Myr ago), ultimately leading to oxygenation of the deep ocean ~580Myr ago, but details of the evolution of atmospheric oxygenation remain uncertain. Here we use chromium (Cr) stable isotopes from banded iron formations (BIFs) to track the presence of Cr(VI) in Precambrian oceans, providing a time-resolved picture of the oxygenation history of the Earth's atmosphere-hydrosphere system. The geochemical behaviour of Cr is highly sensitive to the redox state of the surface environment because oxidative weathering processes produce the oxidized hexavalent [Cr(VI)] form. Oxidation of reduced trivalent [Cr(III)] chromium on land is accompanied by an isotopic fractionation, leading to enrichment of the mobile hexavalent form in the heavier isotope. Our fractionated Cr isotope data indicate the accumulation of Cr(VI) in ocean surface waters ~2.8 to 2.6Gyr ago and a likely transient elevation in atmospheric and surface ocean oxygenation before the first great rise of oxygen 2.45-2.2Gyr ago (the Great Oxidation Event). In ~1.88-Gyr-old BIFs we find that Cr isotopes are not fractionated, indicating a decline in atmospheric oxygen. Our findings suggest that the Great Oxidation Event did not lead to a unidirectional stepwise increase in atmospheric oxygen. In the late Neoproterozoic, we observe strong positive fractionations in Cr isotopes (δ53Cr up to +4.9‰), providing independent support for increased surface oxygenation at that time, which may have stimulated rapid evolution of macroscopic multicellular life. 1. Pluto's atmosphere near perihelion International Nuclear Information System (INIS) A recent stellar occultation has confirmed predictions that Pluto has an atmosphere which is sufficiently thick to uniformly envelope the planet and to extend far above the surface. Pluto's atmosphere consists of methane and perhaps other volatile gases at temperatures below their freezing points; it should regulate the surface temperature of its volatile ices to a globally uniform value. As Pluto approaches and passes through perihelion, a seasonal maximum in the atmospheric bulk and a corresponding minimum in the exposed volatile ice abundance is expected to occur. The lag in maximum atmospheric bulk relative to perihelion will be diagnostic of the surface thermal properties. An estimate of Pluto's atmospheric bulk may result if a global darkening (resulting from the disappearance of the seasonally deposited frosts) occurs before the time of maximum atmospheric bulk. The ice deposited shortly after perihelion may be diagnostic of the composition of Pluto's volatile reservoir 2. Measurement of the Atmospheric $\ CERN Document Server Aartsen, M G; Abdou, Y; Ackermann, M; Adams, J; Aguilar, J A; Ahlers, M; Altmann, D; Andeen, K; Auffenberg, J; Bai, X; Baker, M; Barwick, S W; Baum, V; Bay, R; Beattie, K; Beatty, J J; Bechet, S; Tjus, J Becker; Becker, K -H; Bell, M; Benabderrahmane, M L; BenZvi, S; Berdermann, J; Berghaus, P; Berley, D; Bernardini, E; Bertrand, D; Besson, D Z; Bindig, D; Bissok, M; Blaufuss, E; Blumenthal, J; Boersma, D J; Bohaichuk, S; Bohm, C; Bose1, D; Boser, S; Botner, O; Brayeur, L; Brown, A M; Bruijn, R; Brunner, J; Buitink, S; Carson, M; Casey, J; Casier, M; Chirkin, D; Christy, B; Clark, K; Clevermann, F; Cohen, S; Cowen, D F; Silva, A H Cruz; Danninger, M; Daughhetee, J; Davis, J C; De Clercq, C; De Ridder, S; Descamps, F; Desiati, P; de Vries-Uiterweerd, G; DeYoung, T; Diaz-Velez, J C; Dreyer, J; Dumm, J P; Dunkman, M; Eagan, R; Eberhardt, B; Eisch, J; Ellsworth, R W; Engdegard, O; Euler, S; Evenson, P A; Fadiran, O; Fazely, A R; Fedynitch, A; Feintzeig, J; Feusels, T; Filimonov, K; Finley, C; Fischer-Wasels, T; Flis, S; Franckowiak, A; Franke, R; Frantzen, K; Fuchs, T; Gaisser, T K; Gallagher, J; Gerhardt, L; Gladstone, L; Glusenkamp, T; Goldschmidt, A; Golup, G; Goodman, J A; Gora, D; Grant, D; Gross, A; Grullon, S; Gurtner, M; Ha, C; Ismail, A Haj; Hallgren, A; Halzen, F; Hanson, K; Heereman, D; Heimann, P; Heinen, D; Helbing, K; Hellauer, R; Hickford, S; Hill, G C; Hoffman, K D; Hoffmann, R; Homeier, A; Hoshina, K; Huelsnitz, W; Hulth, P O; Hultqvist, K; Hussain, S; Ishihara, A; Jacobi, E; Jacobsen, J; Japaridze, G S; Jlelati, O; Kappes, A; Karg, T; Karle, A; Kiryluk, J; Kislat, F; Klas, J; Klein, S R; Kohne, J -H; Kohnen, G; Kolanoski, H; Kopke, L; Kopper, C; Kopper, S; Koskinen, D J; Kowalski, M; Krasberg, M; Kroll, G; Kunnen, J; Kurahashi, N; Kuwabara, T; Labare, M; Landsman, H; Larson, M J; Lauer, R; Lesiak-Bzdak, M; Lunemann, J; Madsen, J; Maruyama, R; Mase, K; Matis, H S; McNally, F; Meagher, K; Merck, M; Meszaros, P; Meures, T; Miarecki, S; Middell, E; Milke, N; Miller, J; Mohrmann, L; Montaruli, T; Morse, R; Nahnhauer, R; Naumann, U; Nowicki, S C; Nygren, D R; Obertacke, A; Odrowski, S; Olivas, A; Olivo, M; O'Murchadha, A; Panknin, S; Paul, L; Pepper, J A; Heros, C Perez de los; Pieloth, D; Pirk, N; Posselt, J; Price, P B; Przybylski, G T; Radel, L; Rawlins, K; Redl, P; Resconi, E; Rhode, W; Ribordy, M; Richman, M; Riedel, B; Rodrigues, J P; Rott, C; Ruhe, T; Ruzybayev, B; Ryckbosch, D; Saba, S M; Salameh, T; Sander, H -G; Santander, M; Sarkar, S; Schatto, K; Scheel, M; Scheriau, F; Schmidt, T; Schmitz, M; Schoenen, S; Schoneberg, S; Schonherr, L; Schonwald, A; Schukraft, A; Schulte, L; Schulz, O; Seckel, D; Seo, S H; Sestayo, Y; Seunarine, S; Sheremata, C; Smith, M W E; Soiron, M; Soldin, D; Spiczak, G M; Spiering, C; Stamatikos, M; Stanev, T; Stasik, A; Stezelberger, T; Stokstad, R G; Stoss, A; Strahler, E A; Strom, R; Sullivan, G W; Taavola, H; Taboada, I; Tamburro, A; Ter-Antonyan, S; Tilav, S; Toale, P A; Toscano, S; Usner, M; van der Drift, D; van Eijndhoven, N; Van Overloop, A; van Santen, J; Vehring, M; Voge1, M; Vraeghe, M; Walck, C; Waldenmaier, T; Wallraff, M; Walter, M; Wasserman, R; Weaver, Ch; Wendt, C; Westerhoff, S; Whitehorn, N; Wiebe, K; Wiebusch, C H; Williams, D R; Wissing, H; Wolf, M; Wood, T R; Woschnagg, K; Xu, C; Xu, D L; Xu, X W; Yanez, J P; Yodh, G; Yoshida, S; Zarzhitsky, P; Ziemann, J; Zierke, S; Zilles, A; Zoll, M 2012-01-01 We report the first observation in a high energy neutrino telescope of cascades induced by atmospheric electron neutrinos and by neutral current interactions of atmospheric neutrinos of all flavors. Using data recorded during the first year of operation of IceCube's DeepCore low energy extension, a sample of 1029 events is observed in 281 days of data. The number of observed cascades is$N_{\\rm cascade} = 496 \\pm 66 (stat.) \\pm 88(syst.)$and the rest of the sample consists of residual backgrounds due to atmospheric muons and charged current interactions of atmospheric muon neutrinos. The flux of the atmospheric electron neutrinos is determined in the energy range between approximately 80 GeV and 6 TeV and is consistent with models of atmospheric neutrinos. 3. Atmospheric Circulation of Exoplanets CERN Document Server Showman, Adam P; Menou, Kristen 2009-01-01 We survey the basic principles of atmospheric dynamics relevant to explaining existing and future observations of exoplanets, both gas giant and terrestrial. Given the paucity of data on exoplanet atmospheres, our approach is to emphasize fundamental principles and insights gained from Solar-System studies that are likely to be generalizable to exoplanets. We begin by presenting the hierarchy of basic equations used in atmospheric dynamics, including the Navier-Stokes, primitive, shallow-water, and two-dimensional nondivergent models. We then survey key concepts in atmospheric dynamics, including the importance of planetary rotation, the concept of balance, and scaling arguments to show how turbulent interactions generally produce large-scale east-west banding on rotating planets. We next turn to issues specific to giant planets, including their expected interior and atmospheric thermal structures, the implications for their wind patterns, and mechanisms to pump their east-west jets. Hot Jupiter atmospheric d... 4. Quality and safety of oils and fats obtained as co-products or by-products of the food chain and destined to animal production OpenAIRE Pignoli, Giovanni 2008-01-01 The aim of the first part of this thesis was to evaluate the effect of trans fatty acid- (TFA), contaminant, polycyclic aromatic hydrocarbon (PAH)- and oxidation productenriched diets on the content of TFA and conjugated linoleic acid (CLA) isomers in meat and liver of both poultry and rabbit. The enriched feedings were prepared with preselected fatty co-and by-products that contained low and high levels of TFA (low, palm fatty acid distillate; high, hydrogenated palm fatty aci... 5. Chlorinated and nitrogenous disinfection by-product formation from ozonation and post-chlorination of natural organic matter surrogates. Science.gov (United States) Bond, Tom; Templeton, Michael R; Rifai, Omar; Ali, Hussain; Graham, Nigel J D 2014-09-01 Ozonation before chlorination is associated with enhanced formation of chloropicrin, a halonitromethane disinfection by-product (DBP), during drinking water treatment. In order to elucidate reasons for this, five natural organic matter (NOM) surrogates were treated using both chlorination and ozonation-chlorination under controlled laboratory conditions. Selected surrogates comprised two phenolic compounds, two free amino acids and one dipeptide; these were resorcinol, 3-aminophenol, L-aspartic acid, β-alanine and ala-ala, respectively. Quantified DBPs included chloropicrin, chloroform, dichloroacetonitrile and trichloroacetonitrile. Relative to chlorination alone, increases in the formation of chloropicrin from ozonation-chlorination varied from 138% for 3-aminophenol to 3740% for ala-ala for the four amine surrogates. This indicates that ozone is more effective than chlorine in mediating a rate-limiting oxidation step in chloropicrin formation, most plausibly involving conversion of an amine group to a nitro group. While both hydrophilic and hydrophobic surrogates acted as chloropicrin precursors, ala-ala was the most reactive precursor following ozonation-chlorination. Since peptides are far commoner in drinking water sources than free amino acids, further research into chemical oxidation of these species by ozone and chlorine is recommended. In contrast, oxidation with ozone prior to chlorination reduced chloroform formation moderately for the two phenolic compounds. 6. Worldwide trend of atmospheric mercury since 1995 Directory of Open Access Journals (Sweden) F. Slemr 2011-01-01 Full Text Available Concern about the adverse effects of mercury on human health and ecosystems has led to tightening emission controls since the mid 1980s. But the resulting mercury emissions reductions in many parts of the world are believed to be offset or even surpassed by the increasing emissions in rapidly industrializing countries. Consequently, concentrations of atmospheric mercury are expected to remain roughly constant. Here we show that the worldwide atmospheric mercury concentration have decreased by about 20 to 38% since 1996 as indicated by long term monitoring at stations in the Southern and Northern Hemispheres combined with intermittent measurements of latitudinal distribution over the Atlantic Ocean. The total reduction of the atmospheric mercury burden of this magnitude within 14 yrs is unprecedented among most of atmospheric trace gases and is at odds with the current mercury emission inventories with nearly constant emissions over the period. It suggests a major shift in the biogeochemical cycle of mercury including oceans and soil reservoirs. Decreasing reemissions from the legacy of historical mercury emissions are the most likely explanation for this decline since the hypothesis of an accelerated oxidation rate of elemental mercury in the atmosphere is not supported by the observed trends of other trace gases. Consequently, models of the atmospheric mercury cycle have to include soil and ocean mercury pools and their dynamics to be able to make projections of future trends. 7. Dry matter yields of maize grown with coal combustion by-products International Nuclear Information System (INIS) Major coal combustion by-products (CCBPs) include fly ash, bottom ash, flue gas desulfurization (scrubber sludge) and fluidized bed combustion residues, and coal gasification ashes. Interest in using these products on agricultural land as soil amendments has recently arisen. However, the impact of these products on soils properties and plant growth are unknown. The new technologies in coal power plants are designed to reduce sulfur (S) emissions into the air. Flue Gas Desulfurization (FGD) (scrubber sludge) and Fluidized Bed Combustion (FBC) residues are CCBPs from this new technology. Both of these types of products have received only limited attention relative to agricultural use (Carlson and Adriano, 1992). The FGD products normally result from the addition of limestone slurries to flue gas streams to control sulfur emissions. The final product generally consists of fly ash and Ca-S (sometimes some Mg-S) salts containing different proportions of sulfite/sulfate/carbonate (Santhanam et al., 1979; Miller, 1987). Compositions of products vary extensively dependent on factors such as type of coal used, combustion conditions, and types of devices used for emission control. These products often contain high soluble salts and may contain enhanced amounts of heavy metals. In a few products, much of the sulfite is converted to sulfate and the resulting products contain high CaSO4, (gypsum hydrite). The FBC products normally result from mixing coal and limestone in the furnace in a fluidized bed created by the injection of air. This usually results in an alkaline final product, relatively high in Ca salts (sulfite/sulfate/oxide) with variable amounts of ash whose composition depends on the type of coal and specific boiler systems used (Terman et al., 1978; Korcak, 1980a, 1982). 20 refs., 3 figs 8. The Atmospheric Fate of Organic Nitrogen Compounds Science.gov (United States) Borduas, Nadine Organic nitrogen compounds are present in our atmosphere from biogenic and anthropogenic sources and have impacts on air quality and climate. Due to recent advances in instrumentation, these compounds are being detected in the gas and particle phases, raising questions as to their source, processing and sinks in the environment. With their recently identified role as contributors to aerosol formation and growth, their novel large scale use as solvents in carbon capture and storage (CCS) technology and their emissions from cigarette smoke, it is now important to address the gaps in our understanding of the fate of organic nitrogen. Experimentally and theoretically, I studied the chemical atmospheric fate of specific organic nitrogen compounds in the amine, amide and isocyanate families, yielding information that can be used in chemical transport models to assess the fate of this emerging class of atmospheric molecules. I performed kinetic laboratory studies in a smog chamber to measure the room temperature rate coefficient for reaction with the hydroxyl radical of monoethanolamine, nicotine, and five different amides. I employed online-mass spectrometry techniques to quantify the oxidation products. I found that amines react quickly with OH radicals with lifetimes of a few hours under sunlit conditions, producing amides as oxidation products. My studies on amides revealed that they have much longer lifetimes in the atmosphere, ranging from a few hours to a week. Photo-oxidation of amides produces isocyanates and I investigated these mechanisms in detail using ab initio calculations. Furthermore, I experimentally measured isocyanic acid's Henry's Law constant as well as its hydrolysis rate constants to better understand its sinks in the atmosphere. Finally, I re-examined the structure-activity relationship (SAR) of organic nitrogen molecules for improved model parameterizations. 9. The Atmosphere and Climate of Venus Science.gov (United States) Bullock, M. A.; Grinspoon, D. H. this chapter in terms of the initial forcing due to a perturbation, radiative response, and indirect responses, which are feedbacks — either positive or negative. When applied to one Venus climate model, we found that the albedo-radiative feedback is more important than greenhouse forcing for small changes in atmospheric H2O and SO2. An increase in these gases cools the planet by making the clouds brighter. On geologic timescales the reaction of some atmospheric species (SO2, CO, OCS, S, H2O, H2S, HCl, HF) with surface minerals could cause significant changes in atmospheric composition. Laboratory data and thermochemical modeling have been important for showing that atmospheric SO2 would be depleted in ~10 m.y. if carbonates are available at the surface. Without replenishment, the clouds would disappear. Alternatively, the oxidation of pyrite could add SO2 to the atmosphere while producing stable Fe oxides at the surface. The correlation of near-infrared high emissivity (dark) surface features with three young, large volcanos on Venus is strong evidence for recent volcanic activity at these sites, certainly over the timescale necessary to support the clouds. We address the nature of heterogeneous reactions with the surface and the implications for climate change on Venus. Chemical and mineralogical signatures of past climates must exist at the surface and below, so in situ experiments on the composition of surface layers are vital for reconstructing Venus' past climate. Many of the most Earth-like planets found around other stars will probably resemble Venus or a younger version of Venus. We finish the chapter with discussing what Venus can tell us about life in the universe, since it is an example of a planetary climate rendered uninhabitable. It also resembles our world's likely future. As with the climate history of Venus, however, the timing of predictable climate transitions on the Earth is poorly constrained by the data. 10. Designing Dynamic Atmospheres DEFF Research Database (Denmark) Højlund, Marie; Kinch, Sofie 2012-01-01 This paper addresses the notion of atmospheres from a designerly perspective, and discusses temporal challenges facing interaction designers when acknowledging the dynamic character of it. As atmospheres are created in the relation between body, space, and time, a pragmatic approach seems useful... 11. Proterozoic atmospheric oxygen DEFF Research Database (Denmark) Canfield, Donald Eugene 2014-01-01 This article is concerned with the evolution of atmospheric oxygen concentrations through the Proterozoic Eon. In particular, this article will seek to place the history of atmospheric oxygenation through the Proterozoic Eon in the context of the evolving physical environment including the history... 12. Update on Atmospheric Neutrinos CERN Document Server González-Garciá, M Concepción; Peres, O L G; Stanev, T; Valle, José W F 1998-01-01 We discuss the impact of recent experimental results on the determination of atmospheric neutrino oscillation parameters. We use all published results on atmospheric neutrinos, including the preliminary large statistics data of Super-Kamiokande. We re-analyze the data in terms of both$\ 13. High surface area, electrically conductive nanocarbon-supported metal oxide Energy Technology Data Exchange (ETDEWEB) Worsley, Marcus A.; Han, Thomas Yong-Jin; Kuntz, Joshua D.; Cervantes, Octavio; Gash, Alexander E.; Baumann, Theodore F.; Satcher, Jr., Joe H. 2015-07-14 A metal oxide-carbon composite includes a carbon aerogel with an oxide overcoat. The metal oxide-carbon composite is made by providing a carbon aerogel, immersing the carbon aerogel in a metal oxide sol under a vacuum, raising the carbon aerogel with the metal oxide sol to atmospheric pressure, curing the carbon aerogel with the metal oxide sol at room temperature, and drying the carbon aerogel with the metal oxide sol to produce the metal oxide-carbon composite. The step of providing a carbon aerogel can provide an activated carbon aerogel or provide a carbon aerogel with carbon nanotubes that make the carbon aerogel mechanically robust. 14. MAVEN Imaging UV Spectrograph Results on the Mars Atmosphere and Atmospheric Escape Science.gov (United States) Chaffin, Michael; Schneider, Nick; McClintock, Bill; Stewart, Ian; Deighan, Justin; Jain, Sonal; Clarke, John; Holsclaw, Greg; Montmessin, Franck; Lefevre, Franck; Chaufray, Jean-Yves; Stiepen, Arnaud; Crismani, Matteo; Mayyasi, Majd; Evans, Scott; Stevens, Mike; Yelle, Roger; Jakosky, Bruce 2016-04-01 The Imaging Ultraviolet Spectrograph (IUVS) is one of nine science instruments aboard the Mars Atmosphere and Volatile and EvolutioN (MAVEN) spacecraft, whose payload is dedicated to exploring the upper atmosphere of Mars and understanding the magnitude and drivers of Mars' atmospheric escape rate. IUVS uses ultraviolet light to investigate the lower and upper atmosphere and ionosphere of Mars. The instrument is among the most powerful spectrographs sent to another planet, with several key capabilities: (1) separate Far-UV & Mid-UV channels for stray light control, (2) a high resolution echelle mode to resolve deuterium and hydrogen emission, (3) internal instrument pointing and scanning capabilities to allow complete mapping and nearly continuous operation, and (4) optimization for airglow studies. IUVS, along with other MAVEN instruments, obtains a comprehensive picture of the current state of the Mars upper atmosphere and ionosphere and the processes that control atmospheric escape. We present an overview of selected IUVS results, including (1) the discovery of diffuse aurora at Mars, and its contrast with previously detected discrete aurora localized near crustal magnetic fields; (2) widespread detection of mesospheric clouds; (3) Significant seasonal and short-timescale variability in thermospheric composition; (4) Global ozone maps spanning six months of seasonal evolution; and (5) mapping of the Mars H and O coronas, deriving the escape rates of H and O and their variability. This last is of particular importance for understanding the long term evolution of Mars and its atmosphere, with the observed preset escape of H potentially capable of removing a large fraction of Mars' initial water inventory, and the differential escape of O relative to H potentially providing a net source of oxidizing power to the atmosphere and planet at present, in contrast with a photochemical theory that predicts stoichiometrically balanced escape. The atmospheric and escape 15. Thermodynamic properties of cerium oxide International Nuclear Information System (INIS) Thermodynamic properties of cerium oxides in the CeO2-CeO1.5 composition range are studied. For this purpose method of electromotive force with solid electrolyte is used, equilibrium constants of reduction of cerium oxides by hydrogen are measured. Necessity of using atmosphere of argon or purified nitrogen to work with pyrophoric cerium oxides is stressed. The obtained results and the earlier known literary data on CeO2 and Ce2O3 thermodynamic properties are tabulated. 14 refs.; 5 tabs 16. In situ ruminal crude protein degradability of by-products from cereals, oilseeds and animal origin NARCIS (Netherlands) Habib, G.; Khan, N.A.; Ali, M.; Bezabih, M. 2013-01-01 The aim of this study was to establish a database on in situ ruminal crude protein (CP) degradability characteristics of by-products from cereal grains, oilseeds and animal origin commonly fed to ruminants in Pakistan and South Asian Countries. The oilseed by-products were soybean meal, sunflower me 17. By-Product Formation in Repetitive PCR Amplification of DNA Libraries during SELEX DEFF Research Database (Denmark) Tolle, Fabian; Wilke, Julian; Wengel, Jesper; 2014-01-01 -recognizing aptamers. Little is known about the formation of such by-products when employing nucleic acid libraries as templates. We report on the formation of two different forms of by-products, named ladder- and non-ladder-type observed during repetitive amplification in the course of in vitro selection experiments... 18. Acid mine drainage treatment using by-products from quicklime manufacturing as neutralization chemicals. Science.gov (United States) Tolonen, Emma-Tuulia; Sarpola, Arja; Hu, Tao; Rämö, Jaakko; Lassi, Ulla 2014-12-01 The aim of this research was to investigate whether by-products from quicklime manufacturing could be used instead of commercial quicklime (CaO) or hydrated lime (Ca(OH)2), which are traditionally used as neutralization chemicals in acid mine drainage treatment. Four by-products were studied and the results were compared with quicklime and hydrated lime. The studied by-products were partly burnt lime stored outdoors, partly burnt lime stored in a silo, kiln dust and a mixture of partly burnt lime stored outdoors and dolomite. Present application options for these by-products are limited and they are largely considered waste. Chemical precipitation experiments were performed with the jar test. All the studied by-products removed over 99% of Al, As, Cd, Co, Cu, Fe, Mn, Ni, Zn and approximately 60% of sulphate from acid mine drainage. However, the neutralization capacity of the by-products and thus the amount of by-product needed as well as the amount of sludge produced varied. The results indicated that two out of the four studied by-products could be used as an alternative to quicklime or hydrated lime for acid mine drainage treatment. PMID:25193795 19. Nutritional diversity of agricultural and agro-industrial by-products for ruminant feeding Directory of Open Access Journals (Sweden) J.A.G. Azevêdo 2012-10-01 Full Text Available Fifty-seven by-products were collected from regions throughout Brazil. Chemical composition, in vitro neutral detergent fiber digestibility (IVNDFD, and total digestible nutrients (TDN were determined with the objective of grouping by-products with similar nutritional characteristics. The by-products belonging to group one (G1 presented the highest content of neutral detergent fiber exclusive of ash and nitrogenous compounds [aNDFom(n] and lowest energy content, with 42.5% and 38.8% of IVNDFD and TDN, respectively. A new cluster analysis was carried in order to better characterize G2 by-products, six subgroups (SGs were established (SG1 to SG6. SG1 by-products had the highest and the lowest values for lignin and TDN, respectively. SG2 by-products had the highest aNDFom(n value, with TDN and IVNDFD values greater than 600 and 700g/kg, respectively, and crude protein (CP value below 200g/kg in dry matter (DM. Among all the subgroups, SG3 had the highest TDN (772g/kg and IVNDFD (934g/kg values and the lowest lignin (23g/kg in DM value. The ether extract was what most influenced the hierarchical establishment of residual grouping in SG4. SG5 by-products had the highest concentration of non-fibrous carbohydrate. Different from the other subgroups, SG6 by-products had the highest value of available CP. 20. 40 CFR 63.302 - Standards for by-product coke oven batteries. Science.gov (United States) 2010-07-01 ... batteries. 63.302 Section 63.302 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... National Emission Standards for Coke Oven Batteries § 63.302 Standards for by-product coke oven batteries... oven emissions from each affected existing by-product coke oven battery that exceed any of...	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7503634691238403, "perplexity": 8666.727106083295}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-22/segments/1495463610374.3/warc/CC-MAIN-20170528181608-20170528201608-00453.warc.gz"}
http://noobstarter.com/nootropic-supplements-gnc-best-nootropic-stack-with-vyvanse.html	Safety Warning — Do not exceed recommended dose. Not intended for pregnant or nursing mothers or children under the age of 18. Individuals taking blood thinners, any other medications, or have any known medical conditions should consult a physician before using any herbal supplements. Discontinue use and consult your doctor if any adverse reactions occur. Not intended to medical conditions; consult a physician before beginning any weight loss program. KEEP OUT OF REACH OF CHILDREN. DO NOT USE IF SAFETY SEAL IS DAMAGED OR MISSING. KEEP BOTTLE CLOSED TIGHTLY AND STORE IN A COOL, DRY PLACE. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease. Keep out of reach of children. Do not use if safety seal is damaged or missing. Store in a cool, dry place. CAUTION: Do not exceed recommended dose. St. John’s Wort may contribute to photosensitivity resulting in skin irritation and redness in persons exposed to strong sunlight or tanning booths. Avoid use in patients at risk of bleeding, taking anticoagulants, or with clotting disorders, based on case reports of bleeding. Discontinue use 2-3 weeks prior to some surgical and dental procedures due to increased risk of bleeding. Avoid use in couples who are trying to conceive, based on theoretical reduction of fertility. Pregnant or nursing mothers, children under 18, individuals with history of seizure, taking MAO inhibiting drugs, or with a known medical condition should consult a physician before using this or any dietary supplement. This product is manufactured and packaged in a facility which may also process milk, soy, wheat, egg, peanuts, tree nuts, fish and crustacean shellfish. This product is a dietary supplement. If you feel an adverse reaction, please contact our support staff immediately to notify us of the issue so that we can offer assistance. Please consult with a physician prior to beginning this supplement. This product has not been approved by the Food and Drug Administration. Always consult your physician or licensed qualified healthcare professional before using this product. If you begin to experience any side effects, consult your doctor, discontinue use and contact us for a full refund. Your doctor will have your extensive medical health history as well as knowledge of what other substances you are consuming, which is important when taking a supplement. We recommend that you do not rely solely on the information presented and that you always read labels, warnings, and directions before using or consuming a product. Do not use if seal around cap is broken or missing. ### Broccoli is great source of vitamin K, which is known to enhance cognitive function and improve brainpower. Researchers have reported that because broccoli is high in compounds called glucosinolates, it can slow the breakdown of the neurotransmitter, acetylcholine, which we need for the central nervous system to perform properly and to keep our brains and our memories sharp. Low levels of acetylcholine are associated with Alzheimer's. "Over the years, I have learned so much from the work of Dr. Mosconi, whose accomplished credentials spanning both neuroscience and nutrition are wholly unique. This book represents the first time her studies on the interaction between food and long-term cognitive function reach a general audience. Dr. Mosconi always makes the point that we would eat differently and treat our brains better if only we could see what we are doing to them. From the lab to the kitchen, this is extremely valuable and urgent advice, complete with recommendations that any one of us can take." For starters, it’s one of the highest antioxidant-rich foods known to man, including vitamin C and vitamin K and fiber. Because of their high levels of gallic acid, blueberries are especially good at protecting our brains from degeneration and stress. Get your daily dose of brain berries in an Omega Blueberry Smoothie, Pumpkin Blueberry Pancakes or in a Healthy Blueberry Cobbler. The metal magnesium (Examine.com), like potassium (which didn’t help me), plays many biological roles and has an RDA for me of 400mg which is higher than I likely get (most people apparently get less, with 68% of American adults So the chi-squared believes there is a statistically-significant difference, the two-sample test disagrees, and the binomial also disagrees. Since I regarded it as a dubious theory, can’t see a difference, and the binomial seems like the most appropriate test, I conclude that several months of 1mg iodine did not change my eye color. (As a final test, when I posted the results on the Longecity forum where people were claiming the eye color change, I swapped the labels on the photos to see if anyone would claim something along the lines when I look at the photos, I can see a difference!. I thought someone might do that, which would be a damning demonstration of their biases & wishful thinking, but no one did.) We all wish success came in a pill form. That was the premise of the hour and half Adderall commercial/ thriller film ‘Limitless’ starring Bradley Cooper. In the film he popped a transparent round pill and instantly his brain power skyrocketed- anything became possible. Most of us wished that pill existed- and now it does. Donepezil is a drug that is used to treat Alzheimers, but it’s effects on normal people make Adderall and Vyvanse look like a cup of coffee. The powder itself is quite bulky; the recommended dose to hit 200mg of absorbed magnesium leads to ~7g of powder (so capping will be difficult) and the container provides only 30 doses’ worth (or each dose costs $1!). It’s described as lemon-flavored, and it is, but it’s sickly-sweet unpleasant and since it’s so much powder, takes half a glass of water to dissolve it entirely and wash it down. Subjectively, I notice nothing after taking it for a week. I may try a simple A-B-A analysis of sleep or Mnemosyne, but I’m not optimistic. And given the large expense of LEF’s Magtein, it’s probably a non-starter even if there seems to be an effect. For sleep effects, I will have to look at more reasonably priced magnesium sources. Microdosing involves ingesting small amounts of psychedelics to induce a very subtle physical and mental effect accompanied by a very noticeable, overall positive, health effect. When you take a microdose of a psychedelic, it is typically referred to as a sub-perceptual dose. A sub-perceptual dose will not have a major impact on your ability to function normally, but the effect will definitely be present in your mood and behavior. The microdose of a particular psychedelic is correlated to the lowest dose that will produce a noticeable effect, which is also known as the threshold dose. Since the goal is not to get a hallucinogenic effect, a microdose can be well below the psychedelics threshold dose. By integrating the correct doses of psychedelics into your weekly routine, you can achieve higher creativity levels, more energy, improved mood, increased focus, and better relational skills. There is a growing body of research that shows microdosing to improve depression, anxiety, PTSD, and emotional imbalance, help with alcohol and tobacco addiction, and decrease ADD and ADHD behaviors. I posted a link to the survey on my Google+ account, and inserted the link at the top of all gwern.net pages; 51 people completed all 11 binary choices (most of them coming from North America & Europe), which seems adequate since the 11 questions are all asking the same question, and 561 responses to one question is quite a few. A few different statistical tests seem applicable: a chi-squared test whether there’s a difference between all the answers, a two-sample test on the averages, and most meaningfully, summing up the responses as a single pair of numbers and doing a binomial test: Armodafinil is sort of a purified modafinil which Cephalon sells under the brand-name Nuvigil (and Sun under Waklert21). Armodafinil acts much the same way (see the ADS Drug Profile) but the modafinil variant filtered out are the faster-acting molecules22. Hence, it is supposed to last longer. as studies like Pharmacodynamic effects on alertness of single doses of armodafinil in healthy subjects during a nocturnal period of acute sleep loss seem to bear out; anecdotally, it’s also more powerful, with Cephalon offering pills with doses as low as 50mg. (To be technical, modafinil is racemic: it comes in two forms which are rotations, mirror-images of each other. The rotation usually doesn’t matter, but sometimes it matters tremendously - for example, one form of thalidomide stops morning sickness, and the other rotation causes hideous birth defects.) I usually use Alpha Brain but have found the delivery times and cost per bottle to be too much .Its great to find a UK based nootropic supplement company giving Alpha Brain a run for their Yankee Dollar . Ultra is a very smooth nootropic - i find my thinking clear and my brain feels more alert and alive - hard to explain but Ultra makes me feel more 'present' and alive . Highly recommended. 5 STARS! MC (Wales) The ingredients in her recipes are representative of her thinking. Local raw honey. Organic everything. Free-range eggs. Organic, grass-fed whole milk (I assume she means feeding grass to the cows, not feeding it to the milk). Filtered water. Goji berries. Açai berry powder. Ginseng extract with royal jelly and bee pollen. Organic spirulina powder. Even Himalayan pink sea salt, for heaven’s sake! Good grief!! The blood half-life is 12-36 hours; hence two or three days ought to be enough to build up and wash out. A week-long block is reasonable since that gives 5 days for effects to manifest, although month-long blocks would not be a bad choice either. (I prefer blocks which fit in round periods because it makes self-experiments easier to run if the blocks fit in normal time-cycles like day/week/month. The most useless self-experiment is the one abandoned halfway.) It is incredibly easy to abuse and become addicted to methylphenidate, and misuse is shockingly prevalent, even among so-called “non-affected” users: with students, biohackers, soccer moms and busy executives popping it – and many of the other smart drugs below – like candy. It’s also not all it’s cracked up to be. Side effects include insomnia, stomach ache, headache and anorexia. Overdoses (which may occur easily as it can be difficult to estimate and regulate dosage) can lead to agitation, hallucinations, psychosis, lethargy, seizures, tachycardia (rapid heart rate), dysrhythmia (irregular heart rhythms), hypertension and hyperthermia. Methylphenidate is particularly hazardous to developing brains, especially those of younger students who are frequently prescribed the drug or who – often in high school and college – use it without a prescription. The prefrontal cortex, located behind the forehead, is responsible for cognition, personality-expression and decision-making, and develops well into the mid-20s, at which point it takes over as the “rational” part of the brain. In the central nervous system, and particularly in the prefrontal cortex, dopamine levels must have a natural rise and fall in order for healthy rational processes (executive control) to develop. By influencing dopamine levels, methylphenidate can negatively impact this healthy cognitive development, especially when it is abused or used too frequently. Celastrus paniculatus, also known as the Intellect Tree, is perhaps one of the more interesting Ayurvedic medicinal plants that has been used for thousands of years, and one that I personally use quite frequently as part of the supplement “Qualia Mind”. In the Ayurvedic tradition, oil derived from C. paniculatus (Malkanguni oil) is used to enhance memory and intellectual capacity, as well as to improve dream recall and induce lucid dreams. In a study performed on healthy rats, the oil was shown to improve 24-hour memory retention after a single dose, an effect accompanied by a reduction in monoamines like norepinephrine, dopamine and serotonin, indicating a decreased turnover of these neurotransmitters which, in turn, may aid in reducing conditions like depression. In another study with rats, C. paniculatus oil administered for 14 days reversed stress-induced spatial learning and memory impairment and restored working memory. In mice with scopolamine-induced memory deficits, the oil has been shown to improve both spatial and fear memory (a type of fear conditioning through which an organism learns to avoid detrimental situations or events). Traditionally, is taken in seed form, starting with 10 seeds and working up to 15 and finally 20 seeds. Is a powerful antioxidant that can help you deal with the brain aging process caused by the harmful effects of free radicals. This ingredient does an amazing job of protecting you against muscle catabolism and brain deterioration. In addition, it helps your blood vessels to expand, so all essential ingredients and oxygen are delivered to your brain. The traditional Chinese medicine has been using this herb to boost memory and mental performance. Much of what she says is standard health advice. Avoid trans fats. Eat fresh vegetables and fruit. Avoid processed foods. Limit red meat consumption. It’s better to get your nutrients from food than from supplement pills. Exercise, get adequate sleep, and avoid stress. Since the brain runs on glucose, she wouldn’t agree with the low-carb diet folks; she says we need adequate sources of glucose in our diet, and recommends complex carbs, paying attention to the glycemic index. I have personally found that with respect to the NOOTROPIC effect(s) of all the RACETAMS, whilst I have experienced improvements in concentration and working capacity / productivity, I have never experienced a noticeable ongoing improvement in memory. COLURACETAM is the only RACETAM that I have taken wherein I noticed an improvement in MEMORY, both with regards to SHORT-TERM and MEDIUM-TERM MEMORY. To put matters into perspective, the memory improvement has been mild, yet still significant; whereas I have experienced no such improvement at all with the other RACETAMS. Colorful vegetables and fruits—such as leafy greens, peppers, beets, and berries—are high in carotenoids and anthocyanins, antioxidant pigments that provide their bright hues. “Antioxidants protect brain cell linings from the damage caused by free radicals, which are harmful molecules that cause inflammation and result from factors like a poor diet or smoking,” explains Janis Jibrin, RD, adjunct professor of nutrition at American University in Washington, D.C. This is not something you notice when you talk to Seltzer. And though our memory is probably at its peak in our early 20s, few 30-year-olds are aware of a deficit. But Seltzer considers himself a transhumanist, in the mould of the Oxford philosopher Nick Bostrom and the futuristic writer and inventor Ray Kurzweil. Transhumanists are interested in robots, cryogenics and living a really, really long time; they consider biological limitations that the rest of us might accept, or even appreciate, as creaky obstacles to be aggressively surmounted. On the ImmInst (Immortality Institute) forums, Seltzer and other members discuss life-extension strategies and the potential benefits of cognitive enhancers. Some members, Seltzer among them, use a drug called piracetam, which was first marketed by a Belgian pharmaceutical company in 1972 and in recent years has become available in the US from retailers that sell supplements. Although not approved for any use by the FDA, piracetam has been used experimentally on stroke patients - to little effect - and on patients with a rare neurological condition called progressive myoclonus epilepsy, for whom it proved helpful in alleviating muscle spasms. Data on piracetam's benefits for healthy people is virtually nonexistent, but many users believe that the drug increases blood flow to the brain. New psychiatric drugs have a way of creating markets for themselves. Disorders often become widely diagnosed after drugs come along that can alter a set of suboptimal behaviours. In this way Ritalin and Adderall helped make ADHD a household name, and advertisements for antidepressants have helped define shyness as a malady. If there's a pill that can clear up the wavering focus of sleep-deprived youth or mitigate the tip-of-the-tongue experience of middle age, then those rather ordinary states may come to be seen as syndromes. And if you obtain your vitamin C from a multivitamin, you receive other key nutrients that many studies over the years have linked to healthy brain function, including beta carotene, iron, zinc, B12 and folic acid. In the June 1999 issue of the Journal of Biology and Psychiatry, for instance, researchers at Sweden's Gotenborg University reported that older people were more likely to score poorly on word memory tests if they had low levels of folic acid. Ginkgo Biloba, Bacopa Monnieri, and Lion’s Mane: This particular unique blend boosts mental focus, memory, learning, and cognitive performance while reducing anxiety and depression, and I’ve found that it can significantly boost mental alertness for around six hours at a time without any jitteriness or irritability – or any significant amounts of caffeine. It’s important to allow for a grace period of about 12 weeks before you feel the stack’s full potential, so don’t expect immediate results with this combination. The advantage of adrafinil is that it is legal & over-the-counter in the USA, so one removes the small legal risk of ordering & possessing modafinil without a prescription, and the retailers may be more reliable because they are not operating in a niche of dubious legality. Based on comments from others, the liver problem may have been overblown, and modafinil vendors post-2012 seem to have become more unstable, so I may give adrafinil (from another source than Antiaging Central) a shot when my modafinil/armodafinil run out. Ampakines bind to AMPARs to block uptake of glutamate, thereby increasing synaptic responses, and this has indeed been shown to minimize the effects of conditions such as Alzheimer’s. Ampakines are also being studied as possible treatments for schizophrenia, depression, ADHD and more. But there is a huge risk associated with ampakine consumption. They are now tightly regulated because if you exceed a safe dosage, you will begin to suffer neuronal damage from glutamate toxicity, which leads to some of the very conditions that ampakines are thought to attenuate. Ampakine consumption can also lead to a decrease in long-term synaptic depression (LTD), a process by which specific synapses (the space between neurons across which information is sent) are intentionally weakened in order to avoid a plateau in the efficiency of your synapses. In other words, it allows your neurons and their connections to continue growing in efficiency. LTD is believed to be necessary for healthy synaptic plasticity (the adaptability of synapses), memory function and motor skills. To be honest, there is debate over whether cognitive functions like motor learning are truly dependent upon LTD, but it is possible that if you were to take a higher-than-recommended dose of an ampakine, the overstimulation that would result may lead to suppressed LTD and consequently to poor memory and motor function. Amphetamines are synthetic stimulants and were first created in 1887. These are among the most powerful stimulant-based smart drugs in use and work primarily by targeting dopamine, serotonin and noradrenaline/norepinephrine. Given what you’ve already learned about the dopaminergic effects of modafinil and methylphenidate, you should already be wary of amphetamines’ targeting of dopamine. Hormones and neurotransmitters such as dopamine, serotonin, norepinephrine and histamine are known as monoamines, and amphetamines block their uptake by being taken up instead themselves by monoamine transporters. This leads to higher levels of monoamines in synapses, and consequently to the psychostimulant effects characteristic of drugs like Adderall. To our Brainfood students and youth supporters: It’s your potential that inspired us, your laughter that sustained us, your incredible talent that challenged us to dig deep and build programs that you deserve. Whether you were with us for one year or one week, know that there’s probably a Brainfood staffer who has bragged about how awesome you are. We hope that what you learned in Brainfood sticks with you, even if it’s just using that pumpkin chocolate chip muffin recipe to make someone’s day a little brighter. You’ve given us hope and made us so very proud. Thank you. Now go out there, get what’s yours, and bless the world with your many, many talents. Alex remains enthusiastic about Adderall, but he also has a slightly jaundiced critique of it. "It only works as a cognitive enhancer insofar as you are dedicated to accomplishing the task at hand," he said. "The number of times I've taken Adderall late at night and decided that, rather than starting my paper, hey, I'll organise my entire music library! I've seen people obsessively cleaning their rooms on it." Alex thought that generally the drug helped him to bear down on his work, but it also tended to produce writing with a characteristic flaw. "Often I've looked back at papers I've written on Adderall, and they're verbose. They're labouring a point, trying to create this airtight argument. I'd produce two pages on something that could be said in a couple of sentences." Nevertheless, his Adderall-assisted papers usually earned him at least a B. They got the job done. As Alex put it: "Productivity is a good thing." Sun: This is a day I devote to spiritual disciplines and deep personal exploration, along with a hefty dose of neurogenesis, and for a day such as this, I’ll use a more potent neuron sprouting and ego-dissolving mix – most notably a blend of psilocybin microdose with Lion’s Mane extract and niacin (if the skin flush and increased blood flow from niacin tends to be too much for you, you can also use “nicotinamide riboside”, a form of vitamin B3 that has similar effects without the flushing). Nootropics are classically defined as something that a) improves brain health, and b) does no harm. So, while many treatments being advertised online and on TV can be classified as nootropics, some of them don’t fit the bill because of the dangerous and damaging side effects they also confer upon the unwary consumer. In fact, most of the results you might get from searching ‘best brain pills’ are similarly not that great, let alone the best. Blueberries. "Brainberries" is what Steven Pratt, MD, author of Superfoods Rx: Fourteen Foods Proven to Change Your Life, calls these tasty fruits. Pratt, who is also on staff at Scripps Memorial Hospital in La Jolla, Calif., says that in animal studies researchers have found that blueberries help protect the brain from oxidative stress and may reduce the effects of age-related conditions such as Alzheimer's disease or dementia. Studies have also shown that diets rich in blueberries significantly improved both the learning capacity and motor skills of aging rats, making them mentally equivalent to much younger rats. Ann Kulze, MD, author of Dr. Ann's 10-Step Diet: A Simple Plan for Permanent Weight Loss & Lifelong Vitality, recommends adding at least 1 cup of blueberries a day in any form -- fresh, frozen, or freeze-dried. When we first created the BrainSmart Ultra™ range of natural smart drugs and brain supplements in 2007, our main aim was to deliver the most effective balanced natural smart nutrition supplements for the brain available. We wanted to formulate a range of brain health supporting supplements that not only delivered on its promise to help encourage an individual’s mental energy, concentration and memory but also one that contained, at its core, the perfect balance of neurological health supporting ingredients. Nootroo and Nootrobox are two San Francisco nootropics startups that launched last year. Their founders come from the tech scene and their products are squarely aimed at the tech crowd seeking the convenience of not having to build their own combinations. Each claims big-name Silicon Valley entrepreneurs and investors among their users, though neither will name them. If you’re a coffee or tea drinker, keep sipping: Caffeine may help protect against age-related cognitive decline. “Studies have indicated that caffeine—for example, roughly 500 milligrams daily, the equivalent of about five cups of coffee—may help stave off memory issues in humans,” says Bruce Citron, PhD, a neuroscientist at Bay Pines VA Healthcare System and the USF Morsani College of Medicine in Florida. (Experts warn against taking caffeine supplements, which flood your body with a lot of caffeine all at once.) At the Brain Bio Centre, our nutritional therapy clinic, our therapists specialise in mental health and biochemical testing that can provide in-depth information about your own specific needs, so we can create a personalised plan to support your health. For more information, please visit our website: www.brainbiocentre.com. Alternatively, BANT (British Association for Applied Nutrition and Nutritional Therapy), have a large network of therapists you can use to find a therapist suitable for you. These days, young, ambitious professionals prefer prescription stimulants—including methylphenidate (usually sold as Ritalin) and Adderall—that are designed to treat people with attention deficit hyperactivity disorder (ADHD) and are more common and more acceptable than cocaine or nicotine (although there is a black market for these pills). ADHD makes people more likely to lose their focus on tasks and to feel restless and impulsive. Diagnoses of the disorder have been rising dramatically over the past few decades—and not just in kids: In 2012, about 16 million Adderall prescriptions were written for adults between the ages of 20 and 39, according to a report in the New York Times. Both methylphenidate and Adderall can improve sustained attention and concentration, says Barbara Sahakian, professor of clinical neuropsychology at the University of Cambridge and author of the 2013 book Bad Moves: How Decision Making Goes Wrong, and the Ethics of Smart Drugs. But the drugs do have side effects, including insomnia, lack of appetite, mood swings, and—in extreme cases—hallucinations, especially when taken in amounts the exceed standard doses. Take a look at these 10 foods that help you focus. Factor analysis. The strategy: read in the data, drop unnecessary data, impute missing variables (data is too heterogeneous and collected starting at varying intervals to be clean), estimate how many factors would fit best, factor analyze, pick the ones which look like they match best my ideas of what productive is, extract per-day estimates, and finally regress LLLT usage on the selected factors to look for increases. Nuts and seeds. Nuts and seeds are good sources of vitamin E, says Pratt, explaining that higher levels of vitamin E correspond with less cognitive decline as you get older. Add an ounce a day of walnuts, hazelnuts, Brazil nuts, filberts, almonds, cashews, peanuts, sunflower seeds, sesame seeds, flax seed, and unhydrogenated nut butters such as peanut butter, almond butter, and tahini. Raw or roasted doesn't matter, although if you're on a sodium-restricted diet, buy unsalted nuts. Took pill around 6 PM; I had a very long drive to and from an airport ahead of me, ideal for Adderall. In case it was Adderall, I chewed up the pill - by making it absorb faster, more of the effect would be there when I needed it, during driving, and not lingering in my system past midnight. Was it? I didn’t notice any change in my pulse, I yawned several times on the way back, my conversation was not more voluminous than usual. I did stay up later than usual, but that’s fully explained by walking to get ice cream. All in all, my best guess was that the pill was placebo, and I feel fairly confident but not hugely confident that it was placebo. I’d give it ~70%. And checking the next morning… I was right! Finally. Farah has also been considering the ethical complications resulting from the rise of smart drugs. Don't neuroenhancers confer yet another advantage on the kind of people who already can afford private tutors? Writing last year in the Cavalier Daily, the student newspaper of the University of Virginia, a columnist named Greg Crapanzano argued that neuroenhancers "create an unfair advantage for the users who are willing to break the law in order to gain an edge. These students create work that is dependent on the use of a pill rather than their own work ethic." Of course, it's hard to imagine a university administration that would require students to pee in a cup before entering an exam hall. And even with the aid of a neuroenhancer, you still have to write the essay, conceive the screenplay or finish the grant proposal. Moreover, if you can take credit for work you've done on caffeine or nicotine, then you can take credit for work produced on Provigil. That really says it all: there’s an initial spike in MP, which reads like the promised stimulative effects possibly due to fixing a deficiency (a spike which doesn’t seem to have any counterparts in the previous history of MP), followed by a drastic plunge in the magnesium days but not so much the control days (indicating an acute effect when overloaded with magnesium), a partial recovery during the non-experimental Christmas break, another plunge, and finally recovery after the experiment has ended. Fortunately for me, the FDA decided Smart Powder’s advertising was too explicit and ordered its piracetam sales stopped; I was equivocal at the previous price point, but then I saw that between the bulk discount and the fire-sale coupon, 3kg was only$99.99 (shipping was amortized over that, the choline, caffeine, and tryptophan). So I ordered in September 2010. As well, I had decided to cap my own pills, eliminating the inconvenience and bad taste. 3kg goes a very long way so I am nowhere close to running out of my pills; there is nothing to report since, as the pills are simply part of my daily routine. Legal Disclaimer Do Not exceed recommended dose for Colon Clean. Pregnant or nursing mothers, children under 18, and individuals with a known medical condition should consult a physician before using this or any dietary supplement. Be careful when using supplements with other supplements or prescription pharmaceuticals. This product is not intended to diagnose, treat, cure, or prevent any disease. This product has very nice labeling - very easy to understand and the directions for taking it are immediately at the top of the label in the back. You only have to take or or two tablets a day (preferably with meals) so I 've been taking one a day with my noon meal. I'm a bit surprised that it seems already (after two weeks) that I'm remembering things better (my husband even remarked on it!). Normally, I rely on him for my memory about most things (that, and post-it notes) but I seem to be doing better since taking this supplement. My husband also noticed that I'm in a better mood (more playful and wanting to do things). It has definitely altered my mood - it is winter now where I live and because you don't get as much sunshine and every spare moment is taken up by shoveling, you can get a bit more down in the dumps, which I normally do every year.. It hasn't been like that this year and I feel this supplement has a lot to do with that. Thanks #Vitacern!!!! Exercise is also important, says Lebowitz. Studies have shown it sharpens focus, elevates your mood and improves concentration. Likewise, maintaining a healthy social life and getting enough sleep are vital, too. Studies have consistently shown that regularly skipping out on the recommended eight hours can drastically impair critical thinking skills and attention. In 3, you’re considering adding a new supplement, not stopping a supplement you already use. The I don’t try Adderall case has value $0, the Adderall fails case is worth -$40 (assuming you only bought 10 pills, and this number should be increased by your analysis time and a weighted cost for potential permanent side effects), and the Adderall succeeds case is worth $X-40-4099, where$X is the discounted lifetime value of the increased productivity due to Adderall, minus any discounted long-term side effect costs. If you estimate Adderall will work with p=.5, then you should try out Adderall if you estimate that 0.5 \times (X-4179) > 0 ~> $X>4179$. (Adderall working or not isn’t binary, and so you might be more comfortable breaking down the various how effective Adderall is cases when eliciting X, by coming up with different levels it could work at, their values, and then using a weighted sum to get X. This can also give you a better target with your experiment- this needs to show a benefit of at least Y from Adderall for it to be worth the cost, and I’ve designed it so it has a reasonable chance of showing that.) All of the coefficients are positive, as one would hope, and one specific factor (MR7) squeaks in at d=0.34 (p=0.05). The graph is much less impressive than the graph for just MP, suggesting that the correlation may be spread out over a lot of factors, the current dataset isn’t doing a good job of capturing the effect compared to the MP self-rating, or it really was a placebo effect: The content that appears on this page is presented as an overview vs. comparative marketing. The provided information includes product information, overviews, buying guides, and product specifications. All trademarks, registered trademarks and service-marks mentioned on this site are the property of their respective owners. If something is factually inaccurate please contact us and let us know. By contributing your product facts helps to better serve our readers and the accuracy of the content. 2 commenters point out that my possible lack of result is due to my mistaken assumption that if nicotine is absorbable through skin, mouth, and lungs it ought to be perfectly fine to absorb it through my stomach by drinking it (rather than vaporizing it and breathing it with an e-cigarette machine) - it’s apparently known that absorption differs in the stomach. Jump up ^ Sattler, Sebastian; Forlini, Cynthia; Racine, Éric; Sauer, Carsten (August 5, 2013). "Impact of Contextual Factors and Substance Characteristics on Perspectives toward Cognitive Enhancement". PLOS ONE. PLOS. 8 (8): e71452. Bibcode:2013PLoSO...871452S. doi:10.1371/journal.pone.0071452. ISSN 1932-6203. LCCN 2006214532. OCLC 228234657. PMC 3733969. PMID 23940757. Retrieved April 5, 2014. ×	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.2293918877840042, "perplexity": 3100.795917436301}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-47/segments/1542039744750.80/warc/CC-MAIN-20181118221818-20181119003818-00278.warc.gz"}
http://love2d.org/forums/viewtopic.php?f=3&t=77616&start=150	## Code Doodles! General discussion about LÖVE, Lua, game development, puns, and unicorns. PGUp Party member Posts: 105 Joined: Fri Apr 21, 2017 9:17 am ### Re: Code Doodles! frac.png (26.3 KiB) Viewed 13616 times generating fractal, one pixel at a time Code: Select all function getDist(x1, y1, x2, y2) return math.sqrt(math.pow(x2 - x1, 2) + math.pow(y2 - y1, 2)) end function getPos(x, y, rot, dist) return x - math.sin(rot) * dist, y + math.cos(rot) * dist end function getAngle(x1, y1, x2, y2) return math.atan2(x1 - x2, y2 - y1) end math.randomseed(os.time()) lg = love.graphics lw = love.window lw.setMode(500, 500) poly = {} for i=1, 3, 1 do local p = {} table.insert(poly, p) end points = {} local r1 = math.random() local r2 = math.random() local p = {} p.x = (1 - math.sqrt(r1)) * poly[1].x + (math.sqrt(r1) * (1 - r2)) * poly[2].x + (math.sqrt(r1) * r2) * poly[3].x p.y = (1 - math.sqrt(r1)) * poly[1].y + (math.sqrt(r1) * (1 - r2)) * poly[2].y + (math.sqrt(r1) * r2) * poly[3].y table.insert(points, p) --MAX POINTS spawn = 10000 end function love.update() if spawn > 0 then --MODIFY THIS FOR LOOP TO CHANGE THE SPEED OF THE GENERATOR for i=1, 10, 1 do local p = {} local pick = math.random(1, 3) local distance = getDist(points[#points].x, points[#points].y, poly[pick].x, poly[pick].y) local angle = getAngle(points[#points].x, points[#points].y, poly[pick].x, poly[pick].y) p.x, p.y = getPos(points[#points].x, points[#points].y, angle, distance/2) table.insert(points, p) spawn = spawn - 1 end end end function love.draw() for i,v in pairs(poly) do lg.setColor(1,1,1) lg.circle("fill", v.x, v.y, 5) end lg.setColor(1,0,0) for i,v in pairs(points) do lg.circle("fill", v.x, v.y, 1) end end - rmcode Party member Posts: 454 Joined: Tue Jul 15, 2014 12:04 pm Location: Germany Contact: ### Re: Code Doodles! veethree Inner party member Posts: 820 Joined: Sat Dec 10, 2011 7:18 pm ### Re: Code Doodles! Wrote a function that extracts colors from an image. It does this in a very naive way so it only works good sometimes. 1541699302.png (432.87 KiB) Viewed 12837 times The attachment 1541699312.png is no longer available The attachment 1541699302.png is no longer available Code: Select all function love.load() http = require("socket.http") s = "" love.window.setMode(640, 480) love.graphics.setLineStyle("rough") local img = getImage() image = love.graphics.newImage(img) color = scanImage(img) sprint("Total pixels: "..(640 * 480)) sprint("Extracted colors: "..#color) sprint("Hold space to show colors") end function sprint(t) s = s..t.."\n" end function scanImage(data, skip, distance) skip = skip or 10 distance = distance or 1 local colors = {} for y=0, data:getHeight()-1, skip do for x=0, data:getWidth()-1, skip do local r, g, b, a = data:getPixel(x, y) for i,v in ipairs(colors) do if colorDistance(v, {r, g, b, a}) < distance then end end colors[#colors + 1] = {r, g, b, a} end end end return colors end function love.update(dt) end function love.draw() if image then love.graphics.draw(image) end for i,v in ipairs(color) do love.graphics.setColor(v) love.graphics.rectangle("fill", (love.graphics.getWidth() / #color) * (i - 1), love.graphics.getHeight() - 64, love.graphics.getWidth() / #color, 64) end love.graphics.setColor(1, 1, 1) love.graphics.print(s, 12, 12) end function love.keypressed(key) if key == "escape" then love.event.push("quit") end if key == "r" then end if key == "1" then love.graphics.captureScreenshot(os.time()..".png") end end function colorDistance(a, b) return math.abs(a[1] - b[1]) + math.abs(a[2] - b[2]) + math.abs(a[3] - b[3]) end function getImage() local body, code = http.request("https://picsum.photos/640/480/?random") local data = false if body then love.filesystem.write("tmp.jpg", body) data = love.image.newImageData("tmp.jpg") love.filesystem.remove("tmp.jpg") else error(code) end return data end pgimeno Party member Posts: 2181 Joined: Sun Oct 18, 2015 2:58 pm ### Re: Code Doodles! I made this to visualize the bias in formulas for picking random points from the surface of a unit sphere, using four different methods. It rotates the sphere (in orthographic projection) so it can be seen from several angles. It looked nice so I thought I'd add it to this thread too: Code: Select all local rng local sin, cos, sqrt, pi = math.sin, math.cos, math.sqrt, math.pi local tf = love.math.newTransform() local tf2 = love.math.newTransform() local pts = {} local npts = 80000 local function randvec3d_1() local x = rng:random() * 2 * pi local y = rng:random() * 2 * pi local z = sin(y) return { x = cos(x) * z, y = sin(x) * z, z = cos(y) } end local function randvec3d_2() local x = rng:random() * 2 - 1 local y = rng:random() * 2 - 1 local z = rng:random() * 2 - 1 local r = sqrt(xx+yy+zz) return {x = x/r, y = y/r, z = z/r} end local function randvec3d_3() local x, y, z, r repeat x = rng:random() 2 - 1 y = rng:random() * 2 - 1 z = rng:random() * 2 - 1 r = sqrt(xx+yy+zz) until r >= 0.0001 and r < 1 return {x = x/r, y = y/r, z = z/r} end local function randvec3d_4() local z = rng:random()2 - 1 local a = rng:random()(2pi) local r = sqrt(1 - zz) return { x = rcos(a), y = rsin(a), z = z } end local randvec_3d = randvec3d_1 local function regen() local len = 0 for i = 1, npts do v = randvec_3d() len = len + 3 pts[len - 2] = v.x pts[len - 1] = v.y pts[len] = v.z end end rng = love.math.newRandomGenerator(love.timer.getTime()1000000) regen() end local pt2d = {} function love.update(dt) for i = 1, npts do local x, y, z = pts[i3 - 2], tf:transformPoint(pts[i3 - 1], pts[i3]) pt2d[i2 - 1], pt2d[i2] = tf2:transformPoint(x, y), z end tf:rotate(dt/pi) tf2:rotate(dt/3) end function love.draw() love.graphics.translate(400, 300) love.graphics.scale(290, 290) love.graphics.points(pt2d) end function love.keypressed(_, k) if k == "escape" then return love.event.quit() end if k == "1" then randvec_3d = randvec3d_1 regen() end if k == "2" then randvec_3d = randvec3d_2 regen() end if k == "3" then randvec_3d = randvec3d_3 regen() end if k == "4" then randvec_3d = randvec3d_4 regen() end end The method is chosen with the numbers 1 to 4 in the regular keyboard. Method 1 picks two random angles and uses them as the spherical coordinates of a point in the sphere. This results in a clear clustering near the poles: Method 2 picks three random numbers in [-1, 1] and normalizes the resulting vector. This causes clustering in the projection of the edges and vertices of the cube that circumscribes the sphere: Method 3 is like method 2, but if the length of the vector is > 1 or < 0.0001, it's rejected and another one is picked until one within range is found. The time to obtain a valid vector is unbound, but in practice it doesn't take too many iterations to get a valid one. This results in a good uniform distribution no matter the angle: Method 4 picks a random point in the curved side of a cylinder with radius 1 that circumscribes the sphere, and then projects the cylinder on the sphere horizontally. This results in a uniform distribution too, essentially equal to method 3, so I haven't taken a snapshot for it. We can modify the code to prevent projecting the cylinder, by forcing the radius to 1: Code: Select all -- local r = sqrt(1 - zz) local r = 1 and this is the result: I chose the number of points (npts) so that they can be calculated in a single frame in my computer; you may need to adjust that depending on the required frame rate and how fast your computer is. Attachments random-vector-visualize.love veethree Inner party member Posts: 820 Joined: Sat Dec 10, 2011 7:18 pm ### Re: Code Doodles! This one isn't contained in main.lua, But i'd consider it a doodle. It's a bunch of randomly moving balls who evolve the ability to hit a target and avoid an obstacle via a genetic algorithm. It's pretty heavily inspired by this tutorial. The code is pretty haphazardly thrown together, But it works. Genetic.love ga1.png (53.29 KiB) Viewed 11209 times Attachments ga2.png (52.65 KiB) Viewed 11209 times veethree Inner party member Posts: 820 Joined: Sat Dec 10, 2011 7:18 pm ### Re: Code Doodles! GOO SIMULATOR 2020 You need moonshine for it to work cause i'm bad at shaders. 1560203306.png (10.56 KiB) Viewed 9226 times Code: Select all function love.load() s = "" --love.graphics.setBackgroundColor(1, 1, 1) love.physics.setMeter(40) world = love.physics.newWorld(0, love.physics:getMeter() * 8, true) moonshine = require 'moonshine' blur = moonshine(moonshine.effects.gaussianblur) blur.gaussianblur.sigma = 6 vec4 effect( vec4 color, Image tex, vec2 tc, vec2 sc ) { vec4 pixel = Texel(tex, tc); number avg = (pixel.r + pixel.g + pixel.b) / 3; if (avg > 0.01) { return vec4(1.0, 1.0, 1.0, 1.0) * color; } else { return pixel; } } ]]) balls = {} count = 500 ballSize = 2 sizeVariation = 2 for i=1, count do balls[i] = {} balls[i].body = love.physics.newBody(world, love.graphics.getWidth() / 2 + math.random(), -(ballSize * 2) * i, "dynamic") balls[i].body:setMass(0.1) balls[i].size = ballSize + (sizeVariation * math.random()) balls[i].shape = love.physics.newCircleShape(balls[i].size) balls[i].fixture = love.physics.newFixture(balls[i].body, balls[i].shape, 1) balls[i].fixture:setRestitution(0.3) balls[i].fixture:setFriction(0.1) end walls = {} walls[1] = {} walls[1].body = love.physics.newBody(world, love.graphics.getWidth() / 2, love.graphics.getHeight() - 5, "static") walls[1].shape = love.physics.newRectangleShape(love.graphics.getWidth(), 10) walls[1].fixture = love.physics.newFixture(walls[1].body, walls[1].shape, 1) walls[2] = {} walls[2].body = love.physics.newBody(world, 0, love.graphics.getHeight() / 2, "static") walls[2].shape = love.physics.newRectangleShape(10, love.graphics.getWidth()) walls[2].fixture = love.physics.newFixture(walls[2].body, walls[2].shape, 1) walls[3] = {} walls[3].body = love.physics.newBody(world, love.graphics.getWidth() - 10, love.graphics.getHeight() / 2, "static") walls[3].shape = love.physics.newRectangleShape(10, love.graphics.getWidth()) walls[3].fixture = love.physics.newFixture(walls[3].body, walls[3].shape, 1) walls[4] = {} walls[4].body = love.physics.newBody(world, love.graphics.getWidth() / 2, love.graphics.getHeight() / 2, "static") walls[4].shape = love.physics.newRectangleShape(64, 16) walls[4].fixture = love.physics.newFixture(walls[4].body, walls[4].shape, 1) walls[5] = {} walls[5].body = love.physics.newBody(world, love.graphics.getWidth() / 4, love.graphics.getHeight() / 1.5, "static") walls[5].shape = love.physics.newRectangleShape(0, 0, 100, 8, math.pi / 4) walls[5].fixture = love.physics.newFixture(walls[5].body, walls[5].shape, 1) walls[6] = {} walls[6].body = love.physics.newBody(world, love.graphics.getWidth() - (love.graphics.getWidth() / 4), love.graphics.getHeight() / 1.5, "static") walls[6].shape = love.physics.newRectangleShape(0, 0, 100, 8, -(math.pi / 4)) walls[6].fixture = love.physics.newFixture(walls[6].body, walls[6].shape, 1) player = {} player.body = love.physics.newBody(world, love.graphics.getWidth() / 2, love.graphics.getHeight() / 2, "dynamic") player.size = ballSize * 16 player.body:setMass(player.size * 8) player.speed = 1000 player.maxVel = 200 player.jump = 30 player.shape = love.physics.newCircleShape(player.size) player.fixture = love.physics.newFixture(player.body, player.shape, 1) player.fixture:setRestitution(0.3 * math.random() + 0.2) snow = love.graphics.newCanvas() sprint("'SPACE' to reset") sprint("'R' to make shit fly") end function sprint(t) s = s..t.."\n" end function love.update(dt) local mx, my = love.mouse.getPosition() local xVel, yVel = player.body:getLinearVelocity() local nx, ny = xVel, yVel if love.keyboard.isDown("d") then nx = nx + player.speed * dt if nx > player.maxVel then nx = player.maxVel end elseif love.keyboard.isDown("a") then nx = nx - player.speed * dt if nx < -player.maxVel then nx = -player.maxVel end end player.body:setLinearVelocity(nx, ny) world:update(dt) end function love.draw() love.graphics.setCanvas(snow) love.graphics.clear() blur(function() love.graphics.setColor(1, 1, 1, 1) for i,v in ipairs(balls) do love.graphics.circle("fill", v.body:getX(), v.body:getY(), v.size) end end) else love.graphics.setColor(1, 1, 1, 1) for i,v in ipairs(balls) do love.graphics.circle("fill", v.body:getX(), v.body:getY(), v.size) end end love.graphics.setCanvas() love.graphics.setColor(0.2, 0.8, 0.4, 1) love.graphics.draw(snow) love.graphics.setColor(1, 1, 1, 1) for i,v in ipairs(walls) do love.graphics.polygon("fill", v.body:getWorldPoints(v.shape:getPoints())) end love.graphics.setColor(1, 0.6, 0.4, 1) love.graphics.circle("fill", player.body:getX(), player.body:getY(), player.size) love.graphics.setColor(1, 1, 1, 1) love.graphics.printf(s, 12, 12, love.graphics.getWidth(), "left") love.graphics.printf(love.timer.getFPS(), 0, 12, love.graphics.getWidth(), "center") end function love.keypressed(key) if key == "escape" then love.event.push("quit") elseif key == "space" then elseif key == "1" then elseif key == "2" then love.graphics.captureScreenshot(os.time()..".png") --sprint("Screenshot captured.") end if key == "w" then player.body:applyLinearImpulse(0, -(player.size * 18) ) end if key == "r" then for i,v in ipairs(balls) do v.body:applyLinearImpulse(0, -10 * math.random()) end end end Attachments 1560203302.png (12.35 KiB) Viewed 9226 times pgimeno Party member Posts: 2181 Joined: Sun Oct 18, 2015 2:58 pm ### Re: Code Doodles! While I was watching this demo by Melon Dezign, the shadebobs effect caught my attention. I wondered if I would be able to replicate it with Löve to any degree of accuracy, and well, while it's not identical, I'm pretty satisfied with this result. The first three effects use parameters that mimic those in the demo; the rest are random. Here it is: Code: Select all -- Cache some stuff into locals local love = love local lg = love.graphics local min = math.min local max = math.max local abs = math.abs local sin = math.sin local cos = math.cos local pi = math.pi local random = love.math.random -- Colour scaler from 0..255 to 0..1 local cMult = 0.003922 -- Parameters local decr = 12 local FXs = { -- frequency 1, freq. 2, phase 1, phase 2, num vertices, angular speed, -- initial angle, colour, total time {f1 = 1.2, f2 = 1.4, ph1 = 9.4, ph2 = 3.6, n = 4, w = -3, a0 = pi/4, c = {0, 0, 136cMult}, t = 10}, {f1 = 0.7, f2 = 1.6, ph1 = 43.6, ph2 = 39.4, n = 5, w = -2.05, a0 = 0, c = {255cMult, 142cMult, 7cMult}, t = 10}, {f1 = 3, f2 = 5.7, ph1 = 45.8, ph2 = 2.2, n = 4, w = -3.1, a0 = pi/4, c = {144cMult, 144cMult, 235cMult}, t = 8}, } -- Current effect local fx = {} -- Effect index local idx = 0 -- Freeze frame local frozen = false -- Double buffer local canvas, newCanvas -- Take care of the width and height local W, H, size function love.resize(w, h) if w 0.75 < h then -- Use height as reference W = h / 0.75 H = h else -- Use width as reference W = w H = w * 0.75 end local margin = H * 0.0625 W = W - margin H = H - margin size = H * 0.125 -- Margin W = W - size1.5 H = H - size1.5 -- (re)Create the double buffer if canvas then canvas:release() newCanvas:release() end canvas = lg.newCanvas() newCanvas = lg.newCanvas() end love.resize(lg.getWidth(), lg.getHeight()) -- "Triangle" shader: Map the range 0..0.5 to 0..1 and the range 0.5..1 to 1..0 vec4 effect(vec4 col, Image tex, vec2 texpos, vec2 scrpos) { vec4 c = Texel(tex, texpos); return (1. - abs(2.c - 1.)) col; } ]] uniform Image canvas; vec4 effect(vec4 col, Image tex, vec2 texpos, vec2 scrpos) { return mod(Texel(tex, texpos) * col + Texel(canvas, scrpos/love_ScreenSize.xy), 1.); } ]] -- Angle to draw the polygon at local angle = 0 -- The time for the Lissajous figure local lissatime = 0 -- Prevents releasing objects local cachedobj = {c = {}} local function newBob() lg.setCanvas(canvas) lg.clear(0, 0, 0, 1) lg.setCanvas() idx = idx + 1 if idx < 1 then idx = 1 end fx = FXs[idx] if not fx then fx = cachedobj love.math.setRandomSeed(idx) local colour = cachedobj.c -- Select a colour at full saturation local hue = random() * 6 colour[1] = min(max(abs(hue - 3) - 1, 0), 1) hue = (hue + 2) % 6 colour[2] = min(max(abs(hue - 3) - 1, 0), 1) hue = (hue + 2) % 6 colour[3] = min(max(abs(hue - 3) - 1, 0), 1) -- Set saturation to a random value (increases lightness) -- with high values more likely than low local sat = random() ^ .2 colour[1] = 1 - (1 - colour[1]) * sat colour[2] = 1 - (1 - colour[2]) * sat colour[3] = 1 - (1 - colour[3]) * sat fx.f1 = random()^2 * 5 + 0.5 -- prefer low values fx.f2 = random()^2 * 5 + 0.5 fx.ph1 = random() * 40 fx.ph2 = random() * 40 fx.n = random(3, 6) fx.w = random() * 8 - 4 fx.a0 = random() * (2 * pi) fx.c = colour fx.t = random() * 5 + 7 end lissatime = 0 angle = fx.a0 end newBob() end function love.update(dt) if frozen then return end local lt = lissatime lissatime = lissatime + dt if lissatime > fx.t + fadetime then newBob() end local centreX = cos((lt + fx.ph1) * fx.f1) * (W * 0.5) local centreY = cos((lt + fx.ph2) * fx.f2) * (H * 0.5) -- Copy current canvas to new lg.setCanvas(newCanvas) lg.origin() lg.setColor(1, 1, 1) lg.setBlendMode("replace", "premultiplied") lg.draw(canvas) lg.translate(lg.getWidth()0.5, lg.getHeight()0.5) lg.translate(centreX, centreY) lg.rotate(angle) local d = min(lissatime * 10, 1) * decr -- fixes first frame (??) lg.setColor(d * cMult, d * cMult, d * cMult) lg.circle("fill", 0, 0, size, fx.n) lg.setCanvas() angle = angle + fx.w * dt -- Flip buffers canvas, newCanvas = newCanvas, canvas end function love.draw() -- Draw the current canvas if lissatime >= fx.t then local r = fx.c[1] * a local g = fx.c[2] * a local b = fx.c[3] * a lg.setColor(r, g, b) else lg.setColor(fx.c) end lg.setBlendMode("replace", "premultiplied") lg.draw(canvas) end function love.keypressed(k) if k == "space" then frozen = not frozen end if k == "left" then idx = idx - 2 newBob() end if k == "right" then newBob() end return k == "escape" and love.event.quit() end You can use space to pause/resume, left/right to change effect, esc to exit. Attachments Melonbobs.jpg (25.34 KiB) Viewed 6124 times veethree Inner party member Posts: 820 Joined: Sat Dec 10, 2011 7:18 pm ### Re: Code Doodles! I've been making music for a long time, And every digital audio workstation i've used has a nifty "tap bpm" function. I was curious how that sort of thing works so i made one in löve. The whole code is in a single file, But i wanted to get all fancy with a custom font and a sound effect. The weird aspect ratio is due to the fact i made this with my phone in mind. bpmTapper.love	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3103833794593811, "perplexity": 25646.951509204817}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-29/segments/1593657167808.91/warc/CC-MAIN-20200715101742-20200715131742-00599.warc.gz"}
http://www.physicsforums.com/showthread.php?t=686434	# Orbital hybridisation by asitiaf Tags: hybridisation, orbital P: 19 In sp3 hybridisation, how a tetragon is formed? As per book, in ch4 (methane) there are four sigma bond of same length and strength. But we are having three sp sigma bonds (between s of H and p of C) and one ss sigma bond( between s of H and s of C). Then how can sp and ss sigma bond be of same length and strength? Sci Advisor HW Helper P: 11,863 You don't understand the concept of hybridization. Reread your book. Related Discussions Quantum Physics 11 Chemistry 4 Chemistry 5 Chemistry 3 Chemistry 7	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8446701765060425, "perplexity": 7512.980075352092}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-15/segments/1397609533957.14/warc/CC-MAIN-20140416005213-00037-ip-10-147-4-33.ec2.internal.warc.gz"}
https://physics.stackexchange.com/questions/136667/observing-a-particle-over-a-certain-domain	# Observing a particle over a certain domain I was just thinking: in Quantum Mechanics, we start out with that whole collapsing business by observing the x position of a particle. I was thinking: why do we have to do that? What if we only observe a particle over a specific domain? Let's be more specific. I have an electron trapped in a tube. This tube has very, very thin walls. The potential in these walls is quite large but not infinite. Therefore, there is a probability the particle will quantum tunnel through these walls to the outside. If we let the particle go in the tunnel and wait a short time, this is the sort of wave function we would expect: (or should I say, the wave function's probability distribution) Now, we shoot a photon down the tube between the two barriers (let's assume with 100% certainty the light particle will stay within the walls). There are two outcomes: the light particle keeps on going and doesn't hit the particle (the particle was observed to be outside the walls), or the photon bounces back containing information about the particle's position (the particle was observed to be inside the walls). Now, here's my real question: does the particle's wave function collapse if the particle is outside the boundary? If the particle was observed inside the walls, then it will obviously collapse (the photon contains the definite position of the particle). However, things are more messy outside the tube. Let's imagine the particle does collapse. How can we pluck apart that argument? Well, I didn't say the particle HAS to be let go inside the tube. For all that matters, this could have been the initial wave function: For all practical purposes, the electron could be centered on the moon: so long as there is a probability of observing the particle in the tube, we will collapse it. Furthermore, if there are two particles with similar wave functions (some probability for either to be in the tube), then we will collapse them both. In conclusion, once this experiment is done, every particle in the universe (technically on the light-cone) will simultaneously be collapsed. Doesn't sound very physical, does it? Just to determine whether the 0.000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001% chance that the particle might be observed in the tube isn't a very good reason to collapse every wave function in the universe. So, that can't be the case. Then, there is another alternative: we don't collapse the wave function (assuming the particle was not found inside the tube). How can that be the case either? If we didn't collapse the wave function in the first place, how could we know whether the particle was inside the tube or outside it? This is essentially what the problem boils down to: we must collapse the wave function in order to tell whether we need to collapse the wave function. What's the solution here? It looks hopeless either way! Thanks in advance. P.S. There is an easy test to see what's happening, were anyone actually bothered enough to try. Let's assume the photon went right through the tube and showed the particle to be outside. Then, measure the momentum. Do this again and again. If we get a wide range of answers, we know the particle got collapsed each time. Since the particle must have a well defined position, we can't know anything about the momentum. However, if the momentum is well localized (around zero), we know the particle did not collapse. Of course, how localized "well localized" is depends on the time between measuring position and measuring momentum. Thanks again! You cannot measure "where the particle is not at" in this way. When you send a photon it either interacts with the electron, collapsing its wave function, or it doesn't. If it interacts with the electron, then you can say, with some certainty related to the photon energy, where the electron was. But if not, there's nothing you can say about it. It does not mean the electron is outside just that the particles did not interact, for some reason. For example, a photon will never interact with the ground electron in a Hydrogen atom if it does not have at least 13.6 eV. Doesn't mean it is not there. By the way, this "pipe' of yours is about the same as the Hydrogen atom example, the walls are like the binding forces between the nucleus and the electron, and likewise it has specific energy levels permitted for the electron. You could argue that, "ok, but my photon has the required energy and any other quantum number required for the interaction", then comes in that probability distribution you drew. When they interact, and only then, you will find the electron at some point within the tube with that probability, but the photon could still totally "miss" it. Don't forget the photon also has a wave associated with it, it is not everywhere within the tube with the same probability. (Or maybe it's because of the "intrinsic randomness of quantum mechanics". That one always works too. :) But the fact is, when you get the photon "on the other side", it has not interacted with the electron, therefore it has not collapsed its wave function. But also, there's nothing you can say about where the electron is. Furthermore, if there are two particles with similar wave functions (some probability for either to be in the tube), then we will collapse them both. No. Quantum mechanical solutions are exact and deterministic. Their square determines completely the probabilities of observation and each solution has definite boundary conditions that generate it as a model for physical observations. So, 'similar wave functions" has no mathematical meaning , similar is different, as far as QM is concerned. So, we set up a problem, your potential and electron in this case. This is described by a definite wave function , squared giving the probability of finding that electron in a certain (x,y,z,t) , even outside the walls. One electron, one measurement. For example a scatter with another electron, measuring both tracks would give the location of the vertex, which would be the location for this electron at that time. Scattering with a photon needs complicated photon detectors but the same holds: one measurement. To get a probability distribution the experiment should be repeated enough times with different electrons to find the distribution in your plot. If we didn't collapse the wave function in the first place, how could we know whether the particle was inside the tube or outside it? I dislike this collapse business which makes beautiful mathematical structures sound like balloons. We only know what happens to one particle with one measurement at a time, and then get the distribution for a probability plot. This is essentially what the problem boils down to: we must collapse the wave function in order to tell whether we need to collapse the wave function. Meaning? We have to take many measurements with the same boundary conditions to be able to get the probability distribution. There may be need for measurements if the exercise requires it, but the question is not whether one needs a measurement. That is for the experimenter to decide. Maybe you should read similar links to this to get some words to search for, that wills how that tunneling is a well defined phenomenon and even useful in applications of nanotechnology.	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9263358116149902, "perplexity": 324.9722163039499}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-10/segments/1614178364008.55/warc/CC-MAIN-20210302125936-20210302155936-00399.warc.gz"}
http://export.arxiv.org/abs/1103.0043	math.RT (what is this?) # Title: R-groups and parameters Abstract: For classical groups we show the isomorphism of the Knapp-Stein $R$-group, which describes the structure of parabolically induced representations, and the Arthur $R$-group of the parameter associated to the inducing representation by the local Langlands conjecture. We do this in the case of inducing from discrete series representations. In the case of unitary groups we show this isomorphism under a mild assumption on the parameter, which we show holds in at least half the cases. Subjects: Representation Theory (math.RT) MSC classes: 22E50, 11F70, 22E35 Cite as: arXiv:1103.0043 [math.RT] (or arXiv:1103.0043v1 [math.RT] for this version) ## Submission history From: David Goldberg [view email] [v1] Mon, 28 Feb 2011 22:33:05 GMT (18kb) Link back to: arXiv, form interface, contact.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7860540151596069, "perplexity": 2293.9462719382736}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-43/segments/1570986707990.49/warc/CC-MAIN-20191020105426-20191020132926-00319.warc.gz"}
https://socratic.org/questions/is-entropy-state-function-how-prove-it	Chemistry Topics # Is entropy a state function? How? Prove it? Jan 16, 2017 Essentially, this shows a derivation of entropy and that a state function can be written as a total derivative, $\mathrm{dF} \left(x , y\right) = {\left(\frac{\partial F}{\partial x}\right)}_{y} \mathrm{dx} + {\left(\frac{\partial F}{\partial y}\right)}_{x} \mathrm{dy}$. From the first law of thermodynamics: $\mathrm{dU} = \delta {q}_{\text{rev" + deltaw_"rev}}$, where $q$ is the heat flow, $w$ is the work (which we define as $- \int P \mathrm{dV}$), and $\delta$ indicates that heat flow and work are inexact differentials (path functions). Solving for $\delta {q}_{\text{rev}}$ gives: $\delta {q}_{\text{rev" = dU - delw_"rev}} = {C}_{V} \left(T\right) \mathrm{dT} + P \mathrm{dV}$, since ${\left(\frac{\partial U}{\partial T}\right)}_{V} = {C}_{V}$, the constant-volume heat capacity. For an ideal gas, we'd get: $\delta {q}_{\text{rev}} \left(T , V\right) = {C}_{V} \left(T\right) \mathrm{dT} + \frac{n R T}{V} \mathrm{dV}$ It can be shown that this is an inexact total derivative, indicative of a path function. Euler's reciprocity relation states that for the total derivative $\boldsymbol{\mathrm{dF} \left(x , y\right) = M \left(x\right) \mathrm{dx} + N \left(y\right) \mathrm{dy}}$, where $M \left(x\right) = {\left(\frac{\partial F}{\partial x}\right)}_{y}$ and $N \left(y\right) = {\left(\frac{\partial F}{\partial y}\right)}_{x}$, a differential is exact if ${\left(\frac{\partial M}{\partial y}\right)}_{x} = {\left(\frac{\partial N}{\partial x}\right)}_{y}$. If this is the case, this would indicate that we have a state function. Let $M \left(T\right) = {\left(\frac{\partial {q}_{\text{rev}}}{\partial T}\right)}_{V} = {C}_{V} \left(T\right)$, $N \left(V\right) = {\left(\frac{\partial {q}_{\text{rev}}}{\partial V}\right)}_{T} = \frac{n R T}{V}$, $x = T$, and $y = V$. If we use our current expression for $\delta {q}_{\text{rev}}$, we obtain: ((delC_V(T))/(delV))_T stackrel(?" ")(=) ((del(nRT"/"V))/(delT))_V But since ${C}_{V} \left(T\right)$ is only a function of $T$ for an ideal gas, we have: $0 \ne \frac{n R}{V}$ However, if we multiply through by $\frac{1}{T}$, called an integrating factor, we would get a new function of $T$ and $V$ which is an exact differential: $\textcolor{g r e e n}{\frac{\delta {q}_{\text{rev}} \left(T , V\right)}{T} = \frac{{C}_{V} \left(T\right)}{T} \mathrm{dT} + \frac{n R}{V} \mathrm{dV}}$ Now, Euler's reciprocity relation works: ${\left(\frac{\partial \left[{C}_{V} \left(T\right) \text{/"T])/(delV))_T stackrel(?" ")(=) ((del(nR"/} V\right)}{\partial T}\right)}_{V}$ $0 = 0$ color(blue)(sqrt"") Therefore, this new function, $\frac{{q}_{\text{rev}} \left(T , V\right)}{T}$ can be defined as the state function $S$, entropy, which in this case is a function of $T$ and $V$: $\textcolor{b l u e}{\mathrm{dS} \left(T , V\right) = \frac{\delta {q}_{\text{rev}}}{T}}$ and it can be shown that for the definition of the total derivative of $S$: $\mathrm{dS} = {\left(\frac{\partial S}{\partial T}\right)}_{V} \mathrm{dT} + {\left(\frac{\partial S}{\partial V}\right)}_{T} \mathrm{dV}$ $= {\left(\frac{\partial S}{\partial T}\right)}_{V} \mathrm{dT} + {\left(\frac{\partial P}{\partial T}\right)}_{V} \mathrm{dV}$ (where we've used a cyclic relation in the Helmholtz free energy Maxwell relation) which for an ideal gas is: $= \frac{{C}_{V}}{T} \mathrm{dV} + \frac{n R}{V} \mathrm{dV}$ ##### Impact of this question 7714 views around the world	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 39, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9888355135917664, "perplexity": 339.0471466382192}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-43/segments/1570986672431.45/warc/CC-MAIN-20191016235542-20191017023042-00470.warc.gz"}
https://www.preprints.org/manuscript/201801.0089/v1	Preprint Article Version 1 This version not peer reviewed # A New Extension of Extended Caputo Fractional Derivative Operator Version 1 : Received: 9 January 2018 / Approved: 10 January 2018 / Online: 10 January 2018 (09:37:35 CET) How to cite: Rahman, G.; Nisar, K.S.; Mubeen, S. A New Extension of Extended Caputo Fractional Derivative Operator. Preprints 2018, 2018010089 (doi: 10.20944/preprints201801.0089.v1). Rahman, G.; Nisar, K.S.; Mubeen, S. A New Extension of Extended Caputo Fractional Derivative Operator. Preprints 2018, 2018010089 (doi: 10.20944/preprints201801.0089.v1). ## Abstract Recently, different extensions of the fractional derivative operator are found in many research papers. The main aim of this paper is to establish an extension of the extended Caputo fractional derivative operator. The extension of an extended fractional derivative of some elementary functions derives by considering an extension of beta function which includes the Mittag-Leffler function in the kernel. Further, an extended fractional derivative of some familiar special functions, the Mellin transforms of newly defined Caputo fractional derivative operator and the generating relations for extension of extended hypergeometric functions also presented in this study. ## Subject Areas hypergeometric function; beta function; extended hypergeometric function; mellin transform; fractional derivative; caputo fractional derivative; appell's function; generating relation	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8586416840553284, "perplexity": 2570.823178374086}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-09/segments/1518891814140.9/warc/CC-MAIN-20180222160706-20180222180706-00563.warc.gz"}
https://latexref.xyz/bm.html	16.2.2.1 bm: Individual bold math symbols Specifying \boldmath is the best method for typesetting a whole math expression in bold. But to typeset individual symbols within an expression in bold, the bm package provided by the LaTeX Project team is better. Its usage is outside the scope of this document (see its documentation at https://ctan.org/pkg/bm or in your installation) but the spacing in the output of this small example will show that it is an improvement over \boldmath within an expression: \usepackage{bm} % in preamble ... we have $\bm{v} = 5\cdot\bm{u}$	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9231868386268616, "perplexity": 1712.7936705622053}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2023-06/segments/1674764500035.14/warc/CC-MAIN-20230202165041-20230202195041-00555.warc.gz"}
https://chem.libretexts.org/Courses/Pacific_Union_College/Kinetics/06%3A_The_Distribution_of_Gas_Velocities/6.02%3A_Probability_Density_Functions_for_Velocity_Components_in_Spherical_Coordinates	6.2: Probability Density Functions for Velocity Components in Spherical Coordinates We introduce the idea of a three-dimensional probability-density function by showing how to find it from data referred to a Cartesian coordinates system. The probability density associated with a particular molecular velocity is just a number—a number that depends only on the velocity. Given a velocity, the probability density associated with that velocity must be independent of our choice of coordinate system. We can express the three-dimensional probability density using any coordinate system. We turn now to expressing velocities and probability density functions using spherical coordinates. Just as we did for the Cartesian velocity components, we deduce the cumulative probability functions $$f_v\left(v\right)$$, $$f_{\theta }\left(\theta \right)$$, and $$f_{\varphi }\left(\varphi \right)$$ for the spherical-coordinate components. Our deduction of $$f_v\left(v\right)$$ from the experimental data uses $$v$$-values that are associated with all possible values of $$\theta$$ and $$\varphi$$. Corresponding statements apply to our deductions of $$f_{\theta }\left(\theta \right)$$, and $$f_{\varphi }\left(\varphi \right)$$. We also obtain their derivatives, the probability-density functions $${df_v\left(v\right)}/{dv}$$, $${df_{\theta }\left(\theta \right)}/{d\theta }$$, and $${{df}_{\varphi }\left(\varphi \right)}/{d\varphi }$$. From the properties of probability-density functions, we have $\int^{\infty }_0{\left(\frac{{df}_v\left(v\right)}{dv}\right)}dv=\int^{\pi }_0{\left(\frac{{df}_{\theta }\left(\theta \right)}{d\theta }\right)}d\theta =\int^{2\pi }_0{\left(\frac{{df}_{\varphi }\left(\varphi \right)}{d\varphi }\right)}d\varphi =1$ Let $$\textrm{ʋ}\prime$$ be the arbitrarily small increment of volume in velocity space in which the $$v$$-, $$\theta$$-, and $$\varphi$$-components of velocity lie between $$v$$ and $$v+dv$$, $$\theta$$ and $$\theta +d\theta$$, and $$\varphi$$ and $$\varphi +d\varphi$$. Then the probability that the velocity of a randomly selected molecule lies within $$\textrm{ʋ}\prime$$ is $dP\left(\textrm{ʋ}\prime \right)=\left(\frac{df_v\left(v\right)}{dv}\right)\left(\frac{df_{\theta }\left(\theta \right)}{d\theta }\right)\left(\frac{{df}_{\varphi }\left(\varphi \right)}{d\varphi }\right)dvd\theta d\varphi$ Note that the product $\left(\frac{df_v\left(v\right)}{dv}\right)\left(\frac{df_{\theta }\left(\theta \right)}{d\theta }\right)\left(\frac{{df}_{\varphi }\left(\varphi \right)}{d\varphi }\right)$ is not a three-dimensional probability density function. This is most immediately appreciated by recognizing that $$dvd\theta d\varphi$$ is not an incremental “volume” in velocity space. That is, $$\textrm{ʋ}\prime \neq \ dvd\theta d\varphi$$ We let $$\rho \left(v,\ \theta ,\varphi \right)$$ be the probability-density function for the velocity vector in spherical coordinates. When $$v$$, $$\theta$$, and $$\varphi$$ specify the velocity, $$\rho \left(v,\ \theta ,\varphi \right)$$ is the probability per unit volume at that velocity. We want to use $$\rho \left(v,\ \theta ,\varphi \right)$$ to express the probability that an arbitrarily selected molecule has a velocity vector whose magnitude lies between$$\ v$$ and $$v+dv$$, while its $$\theta$$-component lies between $$\theta$$ and $$\theta +d\theta$$, and its $$\varphi$$-component lies between $$\varphi$$ and $$\varphi +d\varphi$$. This is just $$\rho \left(v,\ \theta ,\varphi \right)$$ times the velocity-space “volume” included by these ranges of $$v$$, $$\theta$$, and $$\varphi$$. When we change from Cartesian coordinates, $$\mathop{v}\limits^{\rightharpoonup}=\left(v_x,v_y,v_z\right)$$, to spherical coordinates, $$\mathop{v}\limits^{\rightharpoonup}=\left(v,\theta ,\varphi \right)$$, the transformation is $$v_x=v{\mathrm{sin} \theta \ }{\mathrm{cos} \varphi \ }$$, $$v_y=v{\mathrm{sin} \theta \ }{\mathrm{sin} \varphi \ }$$, $$v_z=v{\mathrm{cos} \theta \ }$$. (See Figure 1.) As sketched in Figure 2, an incremental increase in each of the coordinates of the point specified by the vector $$\left(v,\ \theta ,\varphi \right)$$ advances the vector to the point $$\left(v+dv,\theta +d\theta ,\varphi +d\varphi \right)$$. When $$dv$$, $$d\theta$$, and $$d\varphi$$ are arbitrarily small, these two points specify the diagonally opposite corners of a rectangular parallelepiped, whose edges have the lengths $$dv$$, $$vd\theta$$, and $$v{\mathrm{sin} \theta \ }d\varphi$$. The volume of this parallelepiped is $$v^2{\mathrm{sin} \theta \ }dvd\theta d\varphi$$. Hence, the differential volume elementdifferential volume element in Cartesian coordinates, $$dv_xdv_ydv_z$$, becomes $$v^2{\mathrm{sin} \theta \ }dvd\theta d\varphi$$ in spherical coordinates. Mathematically, this conversion is obtained using the absolute value of the Jacobian, $$J\left(\frac{v_x,v_y,v_z}{v,\theta ,\varphi }\right)$$, of the transformation. That is, $dv_xdv_ydv_z=\left\|J\left(\frac{v_x,v_y,v_z}{v,\theta ,\varphi }\right)\right\|dvd\theta d\varphi$ where the Jacobian is a determinate of partial derivatives $J\left(\frac{v_x,v_y,v_z}{v,\theta ,\varphi }\right)=\left\| \begin{array}{ccc} {\partial v_x}/{\partial v} & {\partial v_x}/{\partial \theta } & {\partial v_x}/{\partial \varphi } \\ {\partial v_y}/{\partial v} & {\partial v_y}/{\partial \theta } & {\partial v_y}/{\partial \varphi } \\ {\partial v_z}/{\partial v} & {\partial v_z}/{\partial \theta } & {\partial v_z}/{\partial \varphi } \end{array} \right\|$ ${=v}^2{\mathrm{sin} \theta \ }$ Since the differential unit of volume in spherical coordinates is $$v^2{\mathrm{sin} \theta \ }$$$$dvd\theta d\varphi$$, the probability that the velocity components lie within the indicated ranges is $dP\left(\textrm{ʋ}\prime \right)=\rho \left(v,\theta ,\varphi \right)v^2{\mathrm{sin} \theta \ }dvd\theta d\varphi$ We can develop the next step in Maxwell’s argument by taking his assumption to mean that the three-dimensional probability density function is expressible as a product of three one-dimensional functions. That is, we take Maxwell’s assumption to assert the existence of independent functions $${\rho }_v\left(v\right)$$, $${\rho }_{\theta }\left(\theta \right)$$, and $${\rho }_{\varphi }\left(\varphi \right)$$ such that $$\rho \left(v,\ \theta ,\varphi \right)={\rho }_v\left(v\right){\rho }_{\theta }\left(\theta \right){\rho }_{\varphi }\left(\varphi \right)$$. The probability that the $$v$$-, $$\theta$$-, and $$\varphi$$-components of velocity lie between $$v$$ and $$v+dv$$, $$\theta$$ and $$\theta +d\theta$$, and $$\varphi$$ and $$\varphi +d\varphi$$ becomes \begin{aligned} dP\left(\textrm{ʋ}\prime \right) & =\left(\frac{df_v\left(v\right)}{dv}\right)\left(\frac{df_{\theta }\left(\theta \right)}{d\theta }\right)\left(\frac{{df}_{\varphi }\left(\varphi \right)}{d\varphi }\right)dvd\theta d\varphi \\ ~ & =\rho \left(v,\theta ,\varphi \right)v^2{\mathrm{sin} \theta dvd\theta d\varphi \ } \\ ~ & ={\rho }_v\left(v\right){\rho }_{\theta }\left(\theta \right){\rho }_{\varphi }\left(\varphi \right)v^2{\mathrm{sin} \theta dvd\theta d\varphi \ } \end{aligned} Since $$v$$, $$\theta$$, and $$\varphi$$ are independent, it follows that $\frac{df_v\left(v\right)}{dv}=v^2{\rho }_v\left(v\right)$ $\frac{df_{\theta }\left(\theta \right)}{d\theta }={\rho }_{\theta }\left(\theta \right){\mathrm{sin} \theta \ }$ $\frac{df_{\varphi }\left(\varphi \right)}{d\varphi }={\rho }_{\varphi }\left(\varphi \right)$ Moreover, the assumption that velocity is independent of direction means that $${\rho }_{\theta }\left(\theta \right)$$ must actually be independent of $$\theta$$; that is, $${\rho }_{\theta }\left(\theta \right)$$ must be a constant. We let this constant be $${\alpha }_{\theta }$$; so$$\ {\rho }_{\theta }\left(\theta \right)={\alpha }_{\theta }$$. By the same argument, we set $${\rho }_{\varphi }\left(\varphi \right)={\alpha }_{\varphi }$$. Each of these probability-density functions must be normalized. This means that $1=\int^{\infty }_0{v^2{\rho }_v\left(v\right)}dv$ $1=\int^{\pi }_0{{\alpha }_{\theta }{\mathrm{sin} \theta \ }d\theta }=2{\alpha }_{\theta }$ $1=\int^{2\pi }_0{{\alpha }_{\varphi }d\varphi }=2\pi {\alpha }_{\varphi }$ from which we see that $${\rho }_{\theta }\left(\theta \right)={\alpha }_{\theta }={1}/{2}$$ and $${\rho }_{\varphi }\left(\varphi \right)={\alpha }_{\varphi }={1}/{2}\pi$$. It is important to recognize that, while $${\rho }_x\left(v_x\right)$$, $${\rho }_y\left(v_y\right)$$, and $${\rho }_z\left(v_z\right)$$ are probability density functions, $${\rho }_{\theta }\left(\theta \right)$$ and $${\rho }_v\left(v\right)$$ are not. (However, $${\rho }_{\varphi }\left(\varphi \right)$$ is a probability density function.) We can see this by noting that, if $${\rho }_{\theta }\left(\theta \right)$$ were a probability density, its integral over all possible values of $$\theta$$ $$\left(0<\theta <\pi \right)$$would be one. Instead, we find $\int^{\pi }_0 \rho_{\theta} \left(\theta \right)d\theta =\int^{\pi }_0 d\theta /2= \pi /2$ Similarly, when we find $${\rho }_v\left(v\right)$$, we can show explicitly that $\int^{\infty }_0{{\rho }_v\left(v\right)dv\neq 1}$ Our notation now allows us to express the probability that an arbitrarily selected molecule has a velocity vector whose magnitude lies between $$v$$ and $$v+dv$$, while its $$\theta$$-component lies between $$\theta$$ and$$\ \theta +d\theta$$, and its $$\varphi$$-component lies between $$\varphi$$ and $$\varphi +d\varphi$$ using three equivalent representations of the probability density function: $dP\left(\textrm{ʋ}\prime \right)=\rho \left(v,\theta ,\varphi \right)v^2{\mathrm{sin} \theta dvd\theta d\varphi \ } - {\rho }_v\left(v\right){\rho }_{\theta }\left(\theta \right){\rho }_{\varphi }\left(\varphi \right)v^2{\mathrm{sin} \theta dvd\theta d\varphi \ }=\left(\frac{1}{4\pi }\right){\rho }_v\left(v\right)v^2{\mathrm{sin} \theta \ }dvd\theta d\varphi$ The three-dimensional probability-density function in spherical coordinates is $\rho \left(v,\ \theta ,\varphi \right)={\rho }_v\left(v\right){\rho }_{\theta }\left(\theta \right){\rho }_{\varphi }\left(\varphi \right)=\frac{{\rho }_v\left(v\right)}{4\pi }$ This shows explicitly that $$\rho \left(v,\ \theta ,\varphi \right)$$ is independent of $$\theta$$ and $$\varphi$$; if the speed is independent of direction, the probability density function that describes velocity must be independent of the coordinates, $$\theta$$ and $$\varphi$$, that specify its direction.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9966093897819519, "perplexity": 194.87363314931937}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-43/segments/1634323585305.53/warc/CC-MAIN-20211020090145-20211020120145-00050.warc.gz"}
https://bookdown.org/yihui/bookdown/publishers.html	## 6.3 Publishers Besides publishing your book online, you can certainly consider publishing it with a publisher. For example, this book was published with Chapman & Hall/CRC, and there is also a free online version at https://bookdown.org/yihui/bookdown/ (with an agreement with the publisher). Another option that you can consider is self-publishing (https://en.wikipedia.org/wiki/Self-publishing) if you do not want to work with an established publisher. It will be much easier to publish a book written with bookdown if the publisher you choose supports LaTeX. For example, Chapman & Hall provides a LaTeX class named krantz.cls, and Springer provides svmono.cls. To apply these LaTeX classes to your PDF book, set documentclass in the YAML metadata of index.Rmd to the class filename (without the extension .cls). The LaTeX class is the most important setting in the YAML metadata. It controls the overall style of the PDF book. There are often other settings you want to tweak, and we will show some details about this book below. The YAML metadata of this book contains these settings: documentclass: krantz lot: yes lof: yes fontsize: 12pt monofont: "Source Code Pro" monofontoptions: "Scale=0.7" The field lot: yes means we want the List of Tables, and similarly, lof means List of Figures. The base font size is 12pt, and we used Source Code Pro as the monospaced (fixed-width) font, which is applied to all program code in this book. In the LaTeX preamble (Section 4.1), we have a few more settings. First, we set the main font to be Alegreya, and since this font does not have the Small Capitals feature, we used the Alegreya SC font. \setmainfont[ UprightFeatures={SmallCapsFont=AlegreyaSC-Regular} ]{Alegreya} The following commands make floating environments less likely to float by allowing them to occupy larger fractions of pages without floating. \renewcommand{\textfraction}{0.05} \renewcommand{\topfraction}{0.8} \renewcommand{\bottomfraction}{0.8} \renewcommand{\floatpagefraction}{0.75} Since krantz.cls provided an environment VF for quotes, we redefine the standard quote environment to VF. You can see its style in Section 2.1. \renewenvironment{quote}{\begin{VF}}{\end{VF}} Then we redefine hyperlinks to be footnotes, because when the book is printed on paper, readers are not able to click on links in text. Footnotes will tell them what the actual links are. \let\oldhref\href \renewcommand{\href}[2]{#2\footnote{\url{#1}}} We also have some settings for the bookdown::pdf_book format in _output.yml: bookdown::pdf_book: includes: before_body: latex/before_body.tex after_body: latex/after_body.tex keep_tex: yes dev: "cairo_pdf" latex_engine: xelatex citation_package: natbib template: null pandoc_args: "--chapters" toc_unnumbered: no toc_appendix: yes quote_footer: ["\\VA{", "}{}"] highlight_bw: yes All preamble settings we mentioned above are in the file latex/preamble.tex. In latex/before_body.tex, we inserted a few blank pages required by the publisher, wrote the dedication page, and specified that the front matter starts: \frontmatter Before the first chapter of the book, we inserted \mainmatter so that LaTeX knows to change the page numbering style from Roman numerals (for the front matter) to Arabic numerals (for the book body). We printed the index in latex/after_body.tex (Section 2.9). The graphical device (dev) for saving plots was set to cairo_pdf so that the fonts are embedded in plots, since the default device pdf does not embed fonts. Your copyeditor is likely to require you to embed all fonts used in the PDF, so that the book can be printed exactly as it looks, otherwise certain fonts may be substituted and the typeface can be unpredictable. The quote_footer field was to make sure the quote footers were right-aligned: the LaTeX command \VA{} was provided by krantz.cls to include the quote footer. The highlight_bw option was set to true so that the colors in syntax highlighted code blocks were converted to grayscale, since this book will be printed in black-and-white. The book was compiled to PDF through xelatex to make it easier for us to use custom fonts. All above settings except the VF environment and the \VA{} command can be applied to any other LaTeX document classes. In case you want to work with Chapman & Hall as well, you may start with the copy of krantz.cls in our repository (https://github.com/rstudio/bookdown/tree/master/inst/examples) instead of the copy you get from your editor. We have worked with the LaTeX help desk to fix quite a few issues with this LaTeX class, so hopefully it will work well for your book if you use bookdown.	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8808004856109619, "perplexity": 2692.4851063405436}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-22/segments/1495463612283.85/warc/CC-MAIN-20170529111205-20170529131205-00383.warc.gz"}
http://mathhelpforum.com/calculus/43284-taylor-series-remainder.html	1. ## Taylor series remainder could anyone help me out with this? thankx use taylor approximation theorem to estimate e with error less than 10^-6 2. Hi Originally Posted by pc31 use taylor approximation theorem to estimate e with error less than 10^-6 Let $f:x\mapsto \exp x$. $f\in\mathcal{C}^{\infty}(\mathbb{R})$ hence for any integer $n$ and for all $a,\,b\in \mathbb{R}$, Taylor's theorem states that $f(b)=\sum_{k=0}^n\frac{f^{(k)}(a)}{k!}(b-a)^k+R_n$ with $R_n=\frac{f^{(n+1)}(c)}{(n+1)!}(b-a)^{n+1}$ for some $c\in[a,b]$. As we want to evaluate $\exp 1$ we choose $b=1$. $a$ can be any real number, let's choose $a=0$, it'll make things easier. For any integer $k$ and for any real number $x$, $f^{(k)}(x)=\exp x$ hence the previous equality becomes $\exp 1=\sum_{k=0}^n\frac{\exp 0}{k!}(1-0)^k+\frac{\exp c}{(n+1)!}(1-0)^{n+1}=\underbrace{\sum_{k=0}^n\frac{1}{k!}}_{\t ext{approximation}}+\underbrace{\frac{\exp c}{(n+1)!}}_{\text{error}}$ for some $c\in[0,1]$. As we want an error $<10^{-6}$, you have to find $n$ such that $\frac{\exp c}{(n+1)!} <10^{-6}$. Can you take it from here ?	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 19, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9947939515113831, "perplexity": 147.13669228893838}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-40/segments/1474738662507.79/warc/CC-MAIN-20160924173742-00214-ip-10-143-35-109.ec2.internal.warc.gz"}
https://physics.stackexchange.com/questions/359777/relativistic-time-dilation-length-contraction	Relativistic time dilation / length contraction [duplicate] I follow that time dilates / distance contracts as you move faster, but sees anomalies in what happens when you slow down again. The time changes are supposedly permanent, with an identical twin ageing a lot more than the twin brother in a rocket accelerating to relativistic speeds... The problem is: Suppose we send the one twin (call him the astronaut-brother) up in a rocket, circling the earth for a day, going close enough to light-speed so that supposedly fifty years pass for the ground-logged twin. Now the rocket slows down and lands. The astronaut brother supposedly finds his brother fifty years older than himself! BUT we know during this process only one day passed for the observer (ground-logged brother). I don't see how the astronaut-brother can possibly find his twin, tens of years older in this scenario, once they're reconciled back in the same time frame? marked as duplicate by John Rennie spacetime StackExchange.ready(function() { if (StackExchange.options.isMobile) return; $('.dupe-hammer-message-hover:not(.hover-bound)').each(function() { var$hover = $(this).addClass('hover-bound'),$msg = $hover.siblings('.dupe-hammer-message');$hover.hover( function() { $hover.showInfoMessage('', { messageElement:$msg.clone().show(), transient: false, position: { my: 'bottom left', at: 'top center', offsetTop: -7 }, dismissable: false, relativeToBody: true }); }, function() { StackExchange.helpers.removeMessages(); } ); }); }); Sep 28 '17 at 15:01 • Your "paradox" has nothing to do with relativity and everything to do with the fact that you made two contradictory assumptions -- "fifty years pass for the ground-logged twin" and "only one day passed for the ground-logged brother". Here's a simpler version of the same paradox: I drove to the store this morning. Over the course of that drive, ten minutes passed on my watch. BUT it's also true that over the course of that drive, twenty minutes passed on my watch. How can I possibly reconcile those facts? – WillO Sep 28 '17 at 14:46 It is the other way around. If you assume that the rocket circles for one Earth day (i.e. until Earth has finished one 360° rotation), then the time that passes for the brother on Earth is exactly one day. However, the astronaut-brother experiences time dilation, and the trip only takes a very short amount of time from his point of view. (This goes to show that, with these problems, one has to take great care to be precise. You said "circling for a day" without specifying how you measure "one day". I assumed that "one day" means one rotation of the Earth. If on the other hand "one day" is measured by a clock on the space ship, then Earth will rotate around the sun many times during that "day" and the brother on ground ages accordingly.) This is a variation of the famous "twin paradox". It is a nice example to show the new ideas that relativity forces. The paradox is resolved with one word: acceleration. Both twins suffer time dilation and see each other older than at rest. That's what looks so disturbing. The thing is that they cannot see each other again unless one of them goes back, for which acceleration is needed, and that breaks everything up, it can even invert efects. In your example, a circular motion is accelerated, so Special Relativity doesn't apply. That's the thing. • If you downvote a question, please add a comment and explain why. I'll be pleased to correct any mistakes and it will help the asker and any reader. – FGSUZ Sep 29 '17 at 18:49	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.4401097297668457, "perplexity": 1344.6409231630798}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-43/segments/1570987756350.80/warc/CC-MAIN-20191021043233-20191021070733-00043.warc.gz"}
http://math.stackexchange.com/questions/157187/how-can-i-alternately-solve-or-otherwise-optimize-the-solution-to-finding-paths	# How can I alternately solve or otherwise optimize the solution to finding paths up a ladder 1 or 2 steps at a time? I got thrown off by an interview question recently, What structure do you use to find all the ways up a ladder with N steps in 1 or 2 steps moves? It occured to me today that a graph expansion could be used but it's not optimal because when N = 30, it evalates almost 700,000 nodes on a single round of expansion. Here's the output of solving for N = 5. 2 2 1 2 1 2 1 2 2 2 1 1 1 1 2 1 1 1 1 2 1 1 1 1 2 1 1 1 1 1 My instinct is that maybe this problem can be solved with regular methods from Discrete Math that I'm just not remembering. Is there a way to get the set of sequences containing (1, 2) where the sum of the elements is N? If anyone is interested here's the code of the program I wrote. - So, just to be sure: you want to actually print all the paths not just the amount of paths? – M.B. Jun 12 '12 at 0:44 Yes, i was asked to say how I'd find all the paths. – Aaron Anodide Jun 12 '12 at 0:50 If $N=0$ there is one way: $\langle\rangle$. (No steps at all.) If $N=1$, there is one way, $\langle 1\rangle$. For $N>1$, take each way up a ladder of $N-2$ steps and append a $2$, and each way up a ladder of $N-1$ steps and append a $1$. Thus, for $N=2$ you get $\langle 2\rangle$ and $\langle 1,1\rangle$. The first few stages, with semicolons separating the paths derived from two steps back from those derived from one step back: \begin{align} &N=0: \langle\rangle\\ &N=1: \langle 1\rangle\\ &N=2: \langle 2\rangle;\langle 1,1\rangle\\ &N=3: \langle 1,2\rangle;\langle 2,1\rangle,\langle 1,1,1\rangle\\ &N=4: \langle 2,2\rangle,\langle 1,1,2\rangle;\langle 1,2,1\rangle,\langle 2,1,1\rangle,\langle 1,1,1,1\rangle \end{align} You never need to have more than two consecutive levels in storage at once, and it’s a straightforward generation with no trial and error. By the way, the number of paths for a given $N$ is $F_{N+1}$, the $(N+1)$-st Fibonacci number, - The number of such paths is the Fibonacci number $F_{n+1}$. You can get the set $S_n$ of $n$-step paths recursively: append $1$ to each member of $S_{n-1}$, $2$ to each member of $S_{n-2}$, and take the union. - Heh. Beat me to the answer by 1 minute. – Rick Decker Jun 12 '12 at 0:59	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5937032699584961, "perplexity": 466.7023071351072}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-27/segments/1435375096738.25/warc/CC-MAIN-20150627031816-00285-ip-10-179-60-89.ec2.internal.warc.gz"}
https://eng.libretexts.org/Bookshelves/Electrical_Engineering/Electronics/Embedded_Controllers_Using_C_and_Arduino_(Fiore)/4%3A_C_Basics_II/4.5%3A_Setting_Clearing_and_Reading_Register_Bits	# 4.5: Setting, Clearing and Reading Register Bits Bitwise operations may appear to be somewhat arcane to the uninitiated but are in fact commonly used. A prime use is in setting, clearing and testing specific bits in registers. One example involves configuring bidirectional ports for input or output mode via a data direction register, typically abbreviated DDR. Each bit of the DDR represents a specific output pin. A logic high might indicate output mode while a logic low would indicate input mode. Assuming DDR is an 8 bit register, if you wanted to set all bits except the 0th bit to input mode, you could write1: DDR = 0x01; // set bit zero to output mode If sometime later you wanted to also set the 1st and 2nd bits to output mode while keeping everything else intact, the easy way to do it is simply to OR the bits you want: DDR = DDR \| 0x06; The prior operation may be performed using the more common shorthand: DDR \|= 0x06; Note that the preceding code does not affect any of the other bits so they stay in whatever mode they were originally. By the way, a set of specific bits (such as the 0x06 above) is often referred to as a bit pattern or bitmask. To see if a specific bit is set, simply AND instead of OR. So, to see if the 1st bit of DDR is set for output mode, you could use something like: if ( DDR & 0x02 ) // true if set Clearing bits requires ANDing with a bitmask that has been complemented. In other words, all 1s and 0s have been reversed in the bit pattern. If, for example, we want to clear the 0th and 4th bits, we’d first complement the bit pattern 0x11 yielding 0xee. Then we AND: DDR &= 0xee; Often, it’s easier to just use the logical complement operator on the original bit pattern and then AND it: DDR &= (~0x11); If you’re dealing with a single bit, you can use the left shift operator so you don’t even have to bother figuring out the bit pattern in hex. To set the 3rd bit and then clear the 4th bit of DDR, you could use the following: DDR \|= (0x01<<3); DDR &= ~(0x01<<4); These operations are so common that they are often invoked using an in-line expansion via a #define. 1. In C, bit position counting, like most sequences, starts from position 0 not position 1.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6055818200111389, "perplexity": 1578.3367245704444}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-43/segments/1634323585450.39/warc/CC-MAIN-20211022021705-20211022051705-00642.warc.gz"}
http://www.konradvoelkel.com/2012/11/homotopy-limits/	### Homotopy limits Tuesday, November 06th, 2012 \| Author: In this short posting, I want to give some intuitive idea on homotopy limits. Homotopy (co)limits appear whenever one has a notion of homotopy equivalence or weak equivalence between objects and one doesn't want to have constructions that distinguish between equivalent objects. The most prominent settings are, of course, classical homotopy theory and homological algebra. Although not necessary for the definition of homotopy (co)limits, I also talk about model categories. First, let us recall what a limit is: Given a small category I (let's think of a diagram like $\cdot \rightarrow \cdot \leftarrow \cdot$) and a functor $D : I \to \mathcal{C}$ (let's think of a diagram in $\mathcal{C}$ that has the prescribed shape), we look at all cones over $D$. A cone over $D$ is just an object $X$ of $\mathcal{C}$ together with morphisms, one for each object $i$ of $I$, from $X$ to $D(i)$, such that these morphisms commute with the morphisms in the image of $D$. This thing is called cone because we can imagine the diagram $D$ to be planar (on a blackboard) and the object $X$ hovers above it, the morphisms down to the diagram look like a cone. It is clear what a morphism between cones should be: a morphism of the objects $X$ that commutes with the morphisms down to the diagram. This yields a category of cones over $D$, conveniently called $Cone(D)$. We call a terminal object in $Cone(D)$ a limit of $D$. It is important to notice that the morphisms down to the diagram in $\mathcal{C}$ are part of the limit, not only the object itself. So, to state it briefly, limits are terminal cones. Homotopy limits are quite similar. They are terminal homotopy cones. Let's see what that means. I will just tell you now what it doesn't mean: homotopy limits are not just limits-up-to-weak equivalence. Homotopy limits are also not just limits computed in the homotopy category. But: Homotopy limits are only well-defined up to weak equivalence (unless you specify to use a particular computational recipe). Technically, that means there is not a unique holim-functor, but we can safely ignore that for a first approximation. We first suppose that we have a category $\mathcal{C}$ equipped with a lluf subcategory $W$, where lluf just means all objects of $\mathcal{C}$ are also in $W$, we just may have fewer morphisms. We call the morphisms in $W$ the weak equivalences of $\mathcal{C}$. We define $Ho(\mathcal{C}) := [W^{-1}]\mathcal{C}$, the homotopy category is the localization along the weak equivalences. Homotopy limits solve the following problem: Suppose I have a diagram in $\mathcal{C}$ but I don't care about replacing the objects by weakly equivalent ones, then what is the terminal cone (up to weak equivalence) not depending on these choices? The difference to a limit in the homotopy category is that we look at honest maps, not morphisms in the homotopy category. So, now we have a vague idea about homotopy limits. How to compute them? That is where model categories appear in the story. In principle, model categories are not necessary to define homotopy limits, and homotopy limits don't depend on a model structure - they depend only on the class of weak equivalences. But model categories allow to compute certain homotopy limits. The default approach: Suppose we have a category $\mathcal{C}$ with a class of weak equivalences as before. Now construct a model category $(W,C,F)$ around. Then suppose the index category $I$ for the diagram you want to compute a homotopy limit of is a Reedy category, which means you can assign a degree to each object and all morphisms can be uniquely factorized in one that lowers degree and one that raises degree (a technical condition, satisfied by most small interesting diagrams). Then there is a convenient model structure on the diagram category $\mathcal{C}^I$ and we can define the homotopy limit as the fibrant replacement in $\mathcal{C}^I$ followed by the ordinary limit. This is a classical derived-functor definition. The crux is: How does the fibrant replacement look like? This question is as hard as any other "how does the injective resolution look like"-type question. Only in particular cases one can really compute a homotopy limit, like for pullbacks. If you have a diagram $X \to Z \leftarrow Y$, it turns out that you can compute the homotopy pullback (in any proper simplicial model category, like topological spaces) by replacing one of the maps by a fibration (that means, replacing $X$ with a weakly equivalent $\tilde{X}$ such that $X \to Z$ factors over $\tilde{X}$ by the weak equivalence $X \to \tilde{X}$ and a fibration $\tilde{X} \to Z$) and then computing the ordinary pullback. I would recommend to read in Dugger's exposition of homotopy colimits to learn more. There is some nice geometric intuition possible for homotopy colimits, which you shouldn't miss! Tags » « Category: English, Mathematics You can leave a response. 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https://www.gradesaver.com/textbooks/math/calculus/university-calculus-early-transcendentals-3rd-edition/chapter-9-section-9-5-absolute-convergence-the-ratio-and-root-tests-exercises-page-515/7	## University Calculus: Early Transcendentals (3rd Edition) Consider $a_n=(-1)^n\dfrac{n^2(n+2)}{ n! 3^{2n}}$ Now, $l=\lim\limits_{n \to \infty} \|\dfrac{a_{n+1}}{a_{n}} \|=\lim\limits_{n \to \infty}\|\dfrac{\dfrac{(n+1)^2(n+1+2)}{ (n+1)! 3^{2n+2}}}{\dfrac{n^2(n+2)}{ n! 3^{2n}}}\|$ Thus, we have $l=\lim\limits_{n \to \infty}\|\dfrac{(n+1)^2 (n+3)}{(9) n^2 (n+1)}\|=\dfrac{1}{9} \lt 1$ Hence, the series Converges absolutely by the ratio test.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9987297058105469, "perplexity": 380.13132906199365}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-16/segments/1585371886991.92/warc/CC-MAIN-20200410043735-20200410074235-00124.warc.gz"}
https://socratic.org/questions/factor-x-4-2x-3-4x-2-6x-3-into-linear-and-quadratic-terms-knowing-that-isqrt-3-i	Precalculus Topics # Factor x^4 - 2x^3 + 4x^2 - 6x + 3 into linear and quadratic terms knowing that -isqrt(3) is a zero? ## I think synthetic division might help. And also this is the real question, ignore the other question that looks very similar. Thanks. Dec 9, 2017 $\left(x + i \sqrt{3}\right) \left(x - i \sqrt{3}\right) {\left(x - 1\right)}^{2}$ #### Explanation: If $x = - i \sqrt{3}$ is zero of this polynomial, $x = i \sqrt{3}$ also zero of it. Hence $\left({x}^{2} + 3\right)$ is multiplier of it. ${x}^{4} - 2 {x}^{3} + 4 {x}^{2} - 6 x + 3$ =${x}^{4} + 3 {x}^{2} - 2 {x}^{3} - 6 x + {x}^{2} + 3$ =${x}^{2} \cdot \left({x}^{2} + 3\right) - 2 x \cdot \left({x}^{2} + 3\right) + {x}^{2} + 3$ =$\left({x}^{2} + 3\right) \cdot \left({x}^{2} - 2 x + 1\right)$ =$\left(x + i \sqrt{3}\right) \left(x - i \sqrt{3}\right) {\left(x - 1\right)}^{2}$ ##### Impact of this question 859 views around the world	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 9, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6600560545921326, "perplexity": 968.803556750356}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-33/segments/1659882573242.55/warc/CC-MAIN-20220818154820-20220818184820-00528.warc.gz"}
https://cstheory.stackexchange.com/questions/19610/number-of-non-isomorphic-codes	Number of non-isomorphic codes We have number of non-isomorphic graphs given in http://planetmath.org/enumeratinggraphs Over an alphabet $q$ how many non-isomorphic $[n,k,d]_q$ codes are possible particularly in the special case of $d=n-k+1$ (MDS case)? The paper here provides number of non-isomorphic $[n,k]_2$ codes without restricting distance. My question has distance restriction. • I would think that this question is much more likely to get an answer in MathOverflow. If it doesn't get an answer here in a few days, you should ask it there. – Peter Shor Nov 1 '13 at 11:25	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6234497427940369, "perplexity": 476.69965182297176}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-35/segments/1566027330800.17/warc/CC-MAIN-20190825194252-20190825220252-00502.warc.gz"}
http://piglix.com/piglix-tmpl.php?title=Sea_ice_concentration	## Sea ice concentration • Sea ice concentration is a useful variable for climate scientists and nautical navigators. It is defined as the area of sea ice relative to the total at a given point in the ocean. This article will deal primarily with its determination from remote sensing measurements. Sea ice concentration helps determine a number of other important climate variables. Since the albedo of ice is much higher than that of water, ice concentration will regulate insolation in the polar oceans. When combined with ice thickness, it determines several other important fluxes between the air and sea, such as salt and fresh-water fluxes between the polar oceans (see for instance bottom water) as well as heat transfer between the atmosphere. Maps of sea ice concentration can be used to determine ice area and ice extent, both of which are important markers of climate change. Ice concentration charts are also used by navigators to determine potentially passable regions—see icebreaker. Measurements from ships and aircraft are based on simply calculating the relative area of ice versus water visible within the scene. This can be done using photographs or by eye. In situ measurements are used to validate remote sensing measurements. Both synthetic aperture radar and visible sensors (such as Landsat) are normally high enough resolution that each pixel is simply classified as a distinct surface type, i.e. water versus ice. The concentration can then be determined by counting the number of ice pixels in a given area which is useful for validating concentration estimates from lower resolution instruments such as microwave radiometers. Since SAR images are normally monochrome and the backscatter of ice can vary quite considerably, classification is normally done based on texture using groups of pixels—see pattern recognition. ${\displaystyle {\vec {T}}_{b}={\vec {T}}_{b0}+\sum _{i=1}^{n}({\vec {T}}_{bi}-{\vec {T}}_{b0})C_{i}}$ Wikipedia	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 1, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8576441407203674, "perplexity": 1202.9632507511922}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-17/segments/1524125944982.32/warc/CC-MAIN-20180421032230-20180421052230-00262.warc.gz"}
https://codeforces.com/problemset/problem/1108/E2	Due to the installation of a new fire alarm in ITMO server room, the system may be occasionally unavailable on the 27-th of May between 06:00 and 15:00 (UTC). × E2. Array and Segments (Hard version) time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output The only difference between easy and hard versions is a number of elements in the array. You are given an array $a$ consisting of $n$ integers. The value of the $i$-th element of the array is $a_i$. You are also given a set of $m$ segments. The $j$-th segment is $[l_j; r_j]$, where $1 \le l_j \le r_j \le n$. You can choose some subset of the given set of segments and decrease values on each of the chosen segments by one (independently). For example, if the initial array $a = [0, 0, 0, 0, 0]$ and the given segments are $[1; 3]$ and $[2; 4]$ then you can choose both of them and the array will become $b = [-1, -2, -2, -1, 0]$. You have to choose some subset of the given segments (each segment can be chosen at most once) in such a way that if you apply this subset of segments to the array $a$ and obtain the array $b$ then the value $\max\limits_{i=1}^{n}b_i - \min\limits_{i=1}^{n}b_i$ will be maximum possible. Note that you can choose the empty set. If there are multiple answers, you can print any. If you are Python programmer, consider using PyPy instead of Python when you submit your code. Input The first line of the input contains two integers $n$ and $m$ ($1 \le n \le 10^5, 0 \le m \le 300$) — the length of the array $a$ and the number of segments, respectively. The second line of the input contains $n$ integers $a_1, a_2, \dots, a_n$ ($-10^6 \le a_i \le 10^6$), where $a_i$ is the value of the $i$-th element of the array $a$. The next $m$ lines are contain two integers each. The $j$-th of them contains two integers $l_j$ and $r_j$ ($1 \le l_j \le r_j \le n$), where $l_j$ and $r_j$ are the ends of the $j$-th segment. Output In the first line of the output print one integer $d$ — the maximum possible value $\max\limits_{i=1}^{n}b_i - \min\limits_{i=1}^{n}b_i$ if $b$ is the array obtained by applying some subset of the given segments to the array $a$. In the second line of the output print one integer $q$ ($0 \le q \le m$) — the number of segments you apply. In the third line print $q$ distinct integers $c_1, c_2, \dots, c_q$ in any order ($1 \le c_k \le m$) — indices of segments you apply to the array $a$ in such a way that the value $\max\limits_{i=1}^{n}b_i - \min\limits_{i=1}^{n}b_i$ of the obtained array $b$ is maximum possible. If there are multiple answers, you can print any. Examples Input 5 4 2 -2 3 1 2 1 3 4 5 2 5 1 3 Output 6 2 4 1 Input 5 4 2 -2 3 1 4 3 5 3 4 2 4 2 5 Output 7 2 3 2 Input 1 0 1000000 Output 0 0 Note In the first example the obtained array $b$ will be $[0, -4, 1, 1, 2]$ so the answer is $6$. In the second example the obtained array $b$ will be $[2, -3, 1, -1, 4]$ so the answer is $7$. In the third example you cannot do anything so the answer is $0$.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6394861340522766, "perplexity": 272.1987353340849}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-22/segments/1558232260358.69/warc/CC-MAIN-20190527005538-20190527031538-00047.warc.gz"}
http://openstudy.com/updates/50f0beeee4b0abb3d86f66c3	Here's the question you clicked on: 55 members online • 0 viewing ## anonymous 3 years ago I am having a problem in arriving at the correct answer to a second order inhomogeneous differential equation (below): Delete Cancel Submit • This Question is Closed 1. anonymous • 3 years ago Best Response You've already chosen the best response. 0 $\frac{ d ^{2}y }{ dx ^{2} }-6\frac{ dy }{ dx }+8y=8e^{4x}$ 2. anonymous • 3 years ago Best Response You've already chosen the best response. 0 I know that the complimentary function is $Ae^{4x}+Be^{2x}$ however i seem to arrive at an incorrect answer for the particular integral. 3. anonymous • 3 years ago Best Response You've already chosen the best response. 0 use the undetermined coefficients method 4. anonymous • 3 years ago Best Response You've already chosen the best response. 0 For the particular integral i get $16Ce^{4x}-24Ce^{4x}+8Ce^{4x}=8e^{4x}$ Based on derivatives of the general function $Ce^{4x}$ I therefore get $e^{4x}(16C-24C+8C)=8e^{4x}$ Therefore $0=8$ Which means there is no solution. The answer in my book for the particular integral however is $4e^{4x}$. Where did i go wrong? 5. anonymous • 3 years ago Best Response You've already chosen the best response. 0 What is the undetermined coefficients method? 6. anonymous • 3 years ago Best Response You've already chosen the best response. 0 Oh, i believe that is what i am doing 7. anonymous • 3 years ago Best Response You've already chosen the best response. 0 your should assume the particular$y = Ce^{kx}$then you solve for C and k 8. anonymous • 3 years ago Best Response You've already chosen the best response. 0 thats what i tried, but i get C = 0 9. anonymous • 3 years ago Best Response You've already chosen the best response. 0 I believe 'k' is actually 4 in this instance. 10. anonymous • 3 years ago Best Response You've already chosen the best response. 0 Can you see where i went wrong in working through the answer? Or do you think it is an error in my book? 11. anonymous • 3 years ago Best Response You've already chosen the best response. 0 wait I am working on it too, if Ce^(kx) won't work, try Cxe^(kx) 12. anonymous • 3 years ago Best Response You've already chosen the best response. 0 Oh... i'll try that only i thought you only did that when there was already a $e^{kx}$ on the LHS. 13. anonymous • 3 years ago Best Response You've already chosen the best response. 0 try$y = Cxe^{4x}$it works 14. anonymous • 3 years ago Best Response You've already chosen the best response. 0 Just trying that now... 15. anonymous • 3 years ago Best Response You've already chosen the best response. 0 Awesome, as you said, that works. I didn't realize that you could use that method when there is no solution of a coefficient. I thought it was only when an element of the general solution appeared in the LHS. Good to know, i've learned a new trick =) 16. anonymous • 3 years ago Best Response You've already chosen the best response. 0 Oh and thanks heaps... =) 17. anonymous • 3 years ago Best Response You've already chosen the best response. 0 lol, you are welcome 18. Not the answer you are looking for? Search for more explanations. • Attachments: Find more explanations on OpenStudy ##### spraguer (Moderator) 5→ View Detailed Profile 23 • Teamwork 19 Teammate • Problem Solving 19 Hero • You have blocked this person. • ✔ You're a fan Checking fan status... Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9998489618301392, "perplexity": 3828.625016025764}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-40/segments/1474738661449.76/warc/CC-MAIN-20160924173741-00158-ip-10-143-35-109.ec2.internal.warc.gz"}
https://tex.stackexchange.com/questions/425811/excluding-columns-with-csvsimple-autotables	# Excluding columns with csvsimple & autotables first my apologies for not providing a full minimum working example. Description: I have a large number of (mainly large) tables in the csv format that I wish to include in a LaTeX document. The job itself is easily achieved with the csvsimple package, calling: \usepackage{longtable} \usepackage{csvsimple} I include my tables using this command: { \small \begingroup\catcode"=9 \csvautolongtable[respect underscore=true]{table_file.csv} \endgroup } Problem: Some of my tables are too wide to fit onto an A4 page, even in landscape mode. However, I have a number of columns that I do not need to include in the document. (They are nice to have, but not absolutely necessary.) Question: Can I exclude specific columns while retaining the use of the \cvsautotable command? In case it helps, this is my header, consistent across the files. The columns I would want to drop are H to Br. Writing a custom header might work, but then I guess it needs a customization of the function to read in the table? (The header includes spaces as well...): Name,dHf ref.(kJ/mol),DFT E0(Eh),DLPNO E0(Eh),ZPVE(J/mol),Htot(J/mol),H,C,N,O,F,Si,P,S,Cl,Br (Yes, I saw the manual - and unfortunately I didn't extract a solution from it...) Many thanks. Thanks to a post from tex.stackexchange ( Importing CSV file as a table in Latex but file too long ), the following approach works: Rather than excluding columns, only the desired columns are picked. Referring to columns by name would be difficult (due to use of the space character for example), so numbers can be used instead. The "autotable" function is replaced with a manually defined layout, specifying a longtable and the header. Columns 1 to 6 are given a name and the name is used to specify the columns printed. \csvreader[longtable=lr\|rrrr,% table head= Name & $\Delta Hf_{ref}$ (\si{kJ/mol}) & % DFT $E_0$ (\si{E_h}) & DLPNO $E_0$ (\si{E_h}) & $ZPVE$ (\si{J/mol}) & $Htot$ (\si{J/mol}) \\ \hline\endhead,% late after line=\\,% ,respect underscore=true]{csv_data_file.csv} {1=\Name,2=\dHfref,3=\EzeroDFT,4=\EzeroDLPNO,5=\ZPVE,6=\Htot}% {\Name & \dHfref & \EzeroDFT & \EzeroDLPNO & \ZPVE & \Htot}% ` Not the most elegant solution, but it works.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8443189859390259, "perplexity": 2380.7979929180246}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-25/segments/1623488286726.71/warc/CC-MAIN-20210621151134-20210621181134-00038.warc.gz"}
http://grephysics.net/ans/8677/94	GR 8677927796770177 \| # Login \| Register GR8677 #94 Problem GREPhysics.NET Official Solution Alternate Solutions Electromagnetism$\Rightarrow$}LR Circuit Once the switch S is closed, although the initial current through the inductor is 0, the change in current through it is maximal. Recalling that $V = -L \dot{I}$, one realizes that the voltage across $A$ must be non-zero at the start. Thus, plots (C), (D), and (E) are eliminated. Now, one must decide between choices (A) and (B). Once the circuit reaches equilibrium, i.e., the elements reach their asymptotic values. Specifically, the voltage at A goes to 0, since the inductor has no potential difference across it (to wit $\dot{I}=0$). Once the switch is opened, the current suddenly changes, and $\dot{I} \neq 0$, thus the inductor has a voltage across it, and the voltage at A becomes nonzero. Because of the diode, this would necessarily have to be a negative voltage. Since there is only $R_2$ to dissipate the voltage, the magnitude of the voltage once the switch is opened should be bigger than that initially, when the switch is closed at $t_0$. Choose (B). Alternate Solutions casseverhart132019-08-13 09:33:49 great problem here. . . tree removalReply to this comment Comments casseverhart13 2019-08-13 09:33:49 great problem here. . . tree removal psychonautQQ 2013-12-22 20:23:25 why does having a diode mean that the voltage at point a would have to be negative? first of all it's a zener diode,second of all even if it wasn't i'd still be confused neo55378008 2012-09-06 13:02:52 We can narrow it down to A or B as the other's pointed out, because we know eventually the energy stored in the inductor will oppose the battery. As for when the switch is opened, just think of an inductive spike. If you've ever had a device with a transformer near powered speakers, you may have heard a pop in the speakers when the device was turned off. The magnetic field around the conductor collapses, and a voltage spike is made. B shows this large spike FatheadVT 2010-11-09 14:17:57 What's the effect of the Ground in this problem? Almno102010-11-12 20:27:39 The ground there keeps the potential on that side of the inductor at zero. Thus, when the current starts and stops, the potential at A has a large non-zero magnitude. Almno102010-11-12 20:29:36 It also forces the potential at A to go to zero as the circuit reaches a steady state, since the inductor will harbor potential difference when the current is steady. The ground is everything here. Almno102010-11-12 20:30:40 will harbor NO potential difference, that is madfish 2007-11-02 19:12:21 always remember: Low Frequencies: inductors are shorts/Capacitors are open circuits High Frequencies: Capacitors are shorts/inductors are open this will help you out greatly to save time wangjj01202008-08-30 13:03:15 What does the comment mean? Who can explain this~ Poop Loops2008-11-05 23:40:06 What that means is that Capacitors cannot pass through DC current. It just builds up. Capacitors only pass current if there is an AC signal. Conversly, Inductors are great for DC currents, since they are just a loop of wire, so it acts like any other wire. But, when you apply some sort of AC signal, the magnetic field around the loops of wire tries to change, inducing another emf from the Inductor to stop it. So Inductors aren't good at passing through AC current. That's why when you first flip the switch in this problem, dI/dt is huge so the emf induced in the Inductor is big. It's even bigger when you close the switch because now current flow the other way, so dI/dt is twice as big as when you first turned on the switch. Jeremy 2007-10-20 12:53:21 After eliminating everything but (A) and (B), it made the most sense to me to consider the time constants ($\tau=L/R$) for the two RL circuits. For the first decay, $\tau_{1}=L/R_{1}$, and for the second, $\tau_{2}=L/R_{2}$. It is given that $R_{2}=3R_{1}$, so that $\tau_{2}=\frac{1}{3}\tau_{1}$, i.e. $\tau_{2} \lt \tau_{1}$. This is answer choice (B). alemsalem2010-09-21 23:25:02 Yeah i think this is the way to go, because of the diode current first runs through R1 only, then when the switch is open it runs through R2 only which should take less time to decay. wzm 2006-11-03 11:43:29 With switch closed, calling emf V, steady state current is $I_{ss}=V/R_{1}$ Open the switch and approximate that the inductor momentarily causes the current through it to remain the same. To do this requires the voltage at the top of the inductor to be $V_{a} =-I_{ss}R_{2}$ $V_{a} = -(V/R_{1})*3R{1} = 3V$ This is approximately what is shown in B. Post A Comment! Username: Password: Click here to register. This comment is best classified as a: (mouseover) Mouseover the respective type above for an explanation of each type. ## Bare Basic LaTeX Rosetta Stone LaTeX syntax supported through dollar sign wrappers $, ex.,$\alpha^2_0$produces $\alpha^2_0$. type this... to get...$\int_0^\infty$$\int_0^\infty$$\partial$$\partial$$\Rightarrow$$\Rightarrow$$\ddot{x},\dot{x}$$\ddot{x},\dot{x}$$\sqrt{z}$$\sqrt{z}$$\langle my \rangle$$\langle my \rangle$$\left( abacadabra \right)_{me}$$\left( abacadabra \right)_{me}$$\vec{E}$$\vec{E}$$\frac{a}{b}\$ $\frac{a}{b}$ The Sidebar Chatbox... Scroll to see it, or resize your browser to ignore it...	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 26, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6884791254997253, "perplexity": 932.9732501978647}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-43/segments/1570986653216.3/warc/CC-MAIN-20191014101303-20191014124303-00065.warc.gz"}
https://dsp.stackexchange.com/questions/35152/spectrograms-for-neural-nets/35154	# Spectrograms for neural nets General Question Given an audio file, say a 16-bit wav, what are some standard methods to preprocess a spectrogram of this wav so that it may be fed into a neural net? Context In Lee et al's 2009 NIPS paper on applying deep belief networks (DBNs) to speech recognition, they briefly mention in Sections 2.2 and 3.1 preprocessing a spectrogram using PCA whitening. NB: I don't have image-processing background as applied to machine learning... Question How may we reproduce the training data that is fed into the DBN in the above NIPS article, section 4.1 for speaker identification in the TIMIT dataset? "We trained the CDBN on unlabeled TIMIT data (as described in Section 3.1)...We computed the first and second-layer CDBN features using the spectrogram as input." Section 3.1 mentinons 20ms window sizes with 10ms overlaps to generate the spectrograms and then applying PCA whitenting. Does this spectrogram -> whitening process produce an $n \times m$ or $n \times m \times t$ array for each speaker? Or do we get an "image" that is somehow fed directly into a (C)DBN? Outlook Based on the NIPS paper, such preprocessing seems standard but I'm (obviously) new to using spectrograms in neural networks. Any python references on spectrograms are appreciated as related to these questions, for example with librosa, pylab, or this tutorial. After generating a spectrogram, perhaps the general steps in this PCA whitening overview can be applied to produce relevant input to a DBN? Example For many supervised classification tasks, we may fit a model via fit(X, y) where $X$ is an $n \times k$ matrix of $n$ samples with $k$ features and $y$ is an $n \times 1$ vector where each row is a corresponding label. Using librosa's melspectogram method on an audio file, we produce an $m \times t$ matrix. With, say, $n$ labeled audio files we would have $n$ training samples each of shape $m \times t$ resulting in an $n \times m \times t$ matrix $X$ (and $n \times 1$ matrix $y$). How may we feed this $X$ into a DBN or neural network in general? The "dimensions" of the spectrogram are not chosen based on where will the spectrogram be fed to but rather depend on your application. Therefore, it is key to understand the spectrogram itself first, as a means of generating features for one or more signals and to an extent, understand the Discrete Fourier Transform (DFT) as well, which is the key operation the spectrogram is based on. In fact, the "dimensions" you are referring to stem entirely from the way the DFT works and determine its spectral "resolution". If you were to run DFT on some discrete time signal ($x[n]$), of maximum length $N$, you would get back a set of coefficients $X[k]$ that decompose the signal to a weighted sum of sinusoids at different frequencies. The range of physical frequencies in $x[n]$ is $\left[ 0 \ldots \frac{F_s}{2} \right]$. However, the DFT decomposes the signal into $N_{FFT}$ frequency bins (indexed by $k$) with $N_{FFT} \le N$. Therefore, the physical frequency that is associated with the $k^{th}$ frequency bin is $f_k = F_s \cdot \frac{k}{N_{FFT}}$. So what?! So, if you are creating a classifier that operates on some $x_m[n]$ sample obtained from the $m^{th}$ speaker and is trying to figure out the gender of the speaker via the range of frequencies audible, then you would have to tune your $N_{FFT}$ in such a way as to be able to assign different frequencies between 85Hz to 225Hz to different frequency bins. If you did not do that, then your spectral features (the set of $k$ frequency bins) would be insensitive to your class $C$ (here $C \in \left\{ male,female \right\}$ and the classification would report poor performance. Alright, so, we keep this consideration of spectral resolution in mind. This actually considers the vertical dimension of the spectrogram. Let's have a look at the spectrogram itself now. The spectrogram is the repetitive application of Short Time Discrete Fourier Transforms (STFT) to a signal in overlapping sections. Let's denote the overlap here with some factor $q \in \left\{ 0 \ldots 1\right)$. When $q=0$ there is no overlap and the spectrogram is evaluated independently on a set of windows (for example $n_{w1} \in \left\{0 \ldots 10 \right\}, n_{w2} \in \left\{11 \ldots 20 \right\}$ and so on). As $q$ approaches $1$, the STFT starts running on overlapping windows (for example $n_{w1} \in \left\{0 \ldots 10 \right\}, n_{w2} \in \left\{5 \ldots 25 \right\}$ and so on). This overlap is desired in the STFT for a number of reasons that are related to the maths of the FT but also the signal itself and the desired analysis on it. The bottom line is that now we have to worry about one more parameter, $q$. So what?!? So, to extend the previous example: Before, we were trying to understand what is the gender of the speaker just by examining a sample of their voice. Let's now assume that we have the recording of a conversation between males and females and we want to produce a list of time instances and their gender classification to examine (for example) if males or females tend to dominate a given discussion. Obviously, we have to tune $N_{FFT}$ from above but now we also have to tune $q$. Too much overlap means a high temporal resolution but also large amount of data (and processing). Too little overlap and we might miss some transition as some speaker was interrupted by some other speaker and then they resumed. If this phenomenon happens within the duration of a window, the STFT cannot resolve different males or females. It's a gray area that contains a mixture of both fundamental frequencies and it will produce some decision that might not be accurate. As you can see, our discussion so far has not involved the classifier itself. The classifier is indeed some $C = f(x_m,\Theta)$ that takes the $m^{th}$ sample and maps it to one of the elements of the set of classes $C$ based on some parameter set $\Theta$. But the only thing we have been talking about so far is how do you construct this set of features that are derived from $x_m$ so that then the $f$ can do its mapping. Let's take a look at that now: Remember how playing around with $q$ produced overlapping windows? Let's take this to the extreme. Let's think about what happens when $q=0.95$. Then, two neighbouring windows actually look very much alike. They differ only in 5% of the samples! Consequently, their spectra (adjacent vertical lines of the spectrogram) are very much alike. Therefore, it is as if we are feeding the classifier redundant data. We are showing the classifier lots of similar examples. Therefore, continuing with the above example, the classifier starts forming an opinion that MALE means all of these similar data that we are feeding into it when MALE, in our world, in the physical world, is conceptually all the different MALE voices across all recordings. A large STFT overlap could lead to overfitting! To brake this similarity of adjacent samples, we introduce whitening. What does whitening do? It shuffles the input matrix, to reduce the covariance between adjacent samples, this is all that the whitening matrix $W$ does (but does it in a mathematical way that takes into account the covariance of the input. It produces an optimal shuffling, so optimal that any covariance between samples has been reduced to zero.) Of course, when you bring Principal Component Analysis (PCA) into the mix, the game is changing slightly because PCA is still on the feature generation side. Applied to our previous example, PCA would enable us to get an indication of how many distinct speakers there might be in a given conversation and express the rest of the samples as coefficients to these distinct speakers (or waveforms). So: As a multi-dimensional array what dimensions should an audio sample's spectrogram have before PCA whitening; It depends on your application and specifically the spectral ($N_{FFT}$) and temporal ($q$) resolutions necessary to resolve unique examples for the classifier. What dimensions should the pre-preocessed object have so that it may be fed into a DBN? It doesn't matter. You can choose to feed the whole thing and let the network "choose" the best input vectors by adjusting its weights OR you could run feature selection and reduce the dimensionality of your input (and the effort to train the network and the time it takes to train it, etc). Hope this helps. EDIT: The paper states "For the application of CDBNs to audio data, we first convert time-domain signals into spectrograms. However, the dimensionality of the spectrograms is large (e.g., 160 channels). We apply PCA whitening to the spectrograms and create lower dimensional representations. Thus, the data we feed into the CDBN consists of $n_c$ channels of one-dimensional vectors of length $n_V$ , where $n_c$ is the number of PCA components in our representation.". Therefore, the input can be considered as "2D". • Thank you! Very generous and informative, esp for a newcomer like me. Some DBN's do seem to require X be "2D" i.e. n x m such as nolearn's dbn. I'll edit my question to specify which part of the NIPS paper I'd like to reproduce. Your insights though should put me on a good path. – Quetzalcoatl Oct 29 '16 at 20:11 • @Ivan You are welcome, glad it was helpful. I am not saying that the "2D" input is impossible, it was just the way I chose to build up to the spectrogram case via its "1D" components. Please see clarification. – A_A Oct 29 '16 at 21:17 • Thanks! So if understood correctly, for each audio sample of a speaker: produce a n x m spectrogram, apply pca whitening to it, and form a collection of n_c - many vectors where each vector has shape [n_v, 1]. Now, assuming one sample each for S speakers, our matrix X would then be a 2D matrix of shape [(n_c * S), n_v] since we have n_c *S number of "samples" each with n_v "features". – Quetzalcoatl Oct 29 '16 at 21:34 • last question: what does it mean to have 160 'channels' in a spectrogram? Do they mean 160 time frames or set of windows? – Quetzalcoatl Nov 6 '16 at 17:16 • $N_{FFT}=160$, equivalent to the "height" of the spectrogram. (The number of "time frames" is the "length" of the spectrogram, its $x$ axis). I am not sure what you mean by "windows" (?). Like, overlapping windows? That would again affect the "length" of the spectrogram. – A_A Nov 6 '16 at 17:35	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7473909258842468, "perplexity": 776.4712082206456}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-31/segments/1627046155458.35/warc/CC-MAIN-20210805063730-20210805093730-00107.warc.gz"}
https://www.gradesaver.com/textbooks/science/physics/college-physics-4th-edition/chapter-10-problems-page-399/40	College Physics (4th Edition) The maximum speed of vibration is $2.5\times 10^{-6}~m/s$ We can find the angular frequency $\omega$: $\omega = 2\pi~f = (2\pi)(4000~Hz) = 8000\pi~rad/s$ We can find the maximum speed: $v_m = A~\omega$ $v_m = (0.10\times 10^{-9}~m)~(8000\pi~rad/s)$ $v_m = 2.5\times 10^{-6}~m/s$ The maximum speed of vibration is $2.5\times 10^{-6}~m/s$.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9562850594520569, "perplexity": 386.4340937614768}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-40/segments/1664030337415.12/warc/CC-MAIN-20221003101805-20221003131805-00765.warc.gz"}
https://www.livmathssoc.org.uk/cgi-bin/sews_diff.py?Axiom	Most recent change of Axiom Edit made on January 08, 2013 by ColinWright at 15:08:22 Deleted text in red / Inserted text in green WW WM An axiom (or postulate) is any mathematical statement that is the starting point from which other statements (often called theorems) are logically derived. Axioms are considered self-evident requiring neither proof nor justification. Many areas of mathematics are based on axioms: set theory, geometry, number theory, probability, /etc./ At the start of 20th Century Mathematicians showed great confidence in the development of the axiomatic foundations of Mathematics. However this confidence was shattered by the work of Kurt Godel. Goedel. One requirement of an axiomatic system is that it is consistent i.e. does not lead to contradictory theorems - thus creating a paradox (see Russell's Paradox). ---- [[[>50 Here are the axioms of Euclidean Geometry * Any two points can be joined by a straight line. * Any straight line segment can be extended indefinitely in a straight line. * Given any straight line segment, a circle can be drawn having the segment as radius and one endpoint as centre. * All right angles are congruent. * If two lines intersect a third in such a way that the sum of the inner angles on one side is less than two right angles, then the two lines inevitably must intersect each other on that side if extended far enough. From these, all the rich and interesting theorems of school geometry can be derived. ]]] It is possible to have different and conflicting axiomatic systems which lead to consistent but different areas of Mathematical study. In Euclidian Geometry the 5th (or parallel) postulate states: * If a line segment intersects two straight lines forming two interior angles on the same side that sum to less than two right angles, then the two lines, if extended indefinitely, meet on that side on which the angles sum to less than two right angles. IMG:ParallelAxiom.svg.png However Nikolai Lobachevsky (1792 - 1856) and János Bolyai (1802 - 1860) considered this axiom was not self-evident. When they investigated the effect of substituting an alternative axiom such that lines do not meet, however far extended, found no resulting contradictions thus formulating the first non-Euclidian Geometry. This Geometry (called hyperbolic geometry) has many features different from Euclidean Geometry. For example, the sum of the angles of a triangle is less than 180 degrees and the greater the area of the triangle the smaller the sum. Poincare's Disc is a model of such a geometry. Different axioms lead to different geometries. Mathematics thus supplies a number of competing descriptions of Space, the correct interpretation being found experimentally. The descriptions of Space by Albert Einstein and others requires Space to be non-Euclidean.	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8770624995231628, "perplexity": 340.99203211421}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-27/segments/1656104204514.62/warc/CC-MAIN-20220702192528-20220702222528-00433.warc.gz"}
https://pytorch.org/ignite/v0.4.7/generated/ignite.metrics.MultiLabelConfusionMatrix.html	MultiLabelConfusionMatrix# class ignite.metrics.MultiLabelConfusionMatrix(num_classes, output_transform=<function MultiLabelConfusionMatrix.<lambda>>, device=device(type='cpu'), normalized=False)[source]# Calculates a confusion matrix for multi-labelled, multi-class data. • update must receive output of the form (y_pred, y). • y_pred must contain 0s and 1s and has the following shape (batch_size, num_classes, …). For example, y_pred[i, j] = 1 denotes that the j’th class is one of the labels of the i’th sample as predicted. • y should have the following shape (batch_size, num_classes, …) with 0s and 1s. For example, y[i, j] = 1 denotes that the j’th class is one of the labels of the i’th sample according to the ground truth. • both y and y_pred must be torch Tensors having any of the following types: {torch.uint8, torch.int8, torch.int16, torch.int32, torch.int64}. They must have the same dimensions. • The confusion matrix ‘M’ is of dimension (num_classes, 2, 2). • M[i, 0, 0] corresponds to count/rate of true negatives of class i • M[i, 0, 1] corresponds to count/rate of false positives of class i • M[i, 1, 0] corresponds to count/rate of false negatives of class i • M[i, 1, 1] corresponds to count/rate of true positives of class i • The classes present in M are indexed as 0, … , num_classes-1 as can be inferred from above. Parameters • num_classes (int) – Number of classes, should be > 1. • output_transform (Callable) – a callable that is used to transform the Engine’s process_function’s output into the form expected by the metric. This can be useful if, for example, you have a multi-output model and you want to compute the metric with respect to one of the outputs. • device (Union[str, torch.device]) – specifies which device updates are accumulated on. Setting the metric’s device to be the same as your update arguments ensures the update method is non-blocking. By default, CPU. • normalized (bool) – whether to normalize confusion matrix by its sum or not. New in version 0.4.5. Methods compute Computes the metric based on it's accumulated state. reset Resets the metric to it's initial state. update Updates the metric's state using the passed batch output. compute()[source]# Computes the metric based on it’s accumulated state. By default, this is called at the end of each epoch. Returns the actual quantity of interest. However, if a Mapping is returned, it will be (shallow) flattened into engine.state.metrics when completed() is called. Return type Any Raises NotComputableError – raised when the metric cannot be computed. reset()[source]# Resets the metric to it’s initial state. By default, this is called at the start of each epoch. Return type None update(output)[source]# Updates the metric’s state using the passed batch output. By default, this is called once for each batch. Parameters output (Sequence[torch.Tensor]) – the is the output from the engine’s process function. Return type None	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7462738156318665, "perplexity": 3605.9659670438878}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-21/segments/1652662517485.8/warc/CC-MAIN-20220517130706-20220517160706-00325.warc.gz"}
https://gmatclub.com/forum/some-people-form-a-joint-account-for-one-year-with-the-condi-159072.html	Check GMAT Club Decision Tracker for the Latest School Decision Releases https://gmatclub.com/AppTrack GMAT Club It is currently 24 Mar 2017, 19:07 GMAT Club Daily Prep Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email. Customized for You we will pick new questions that match your level based on your Timer History Track every week, we’ll send you an estimated GMAT score based on your performance Practice Pays we will pick new questions that match your level based on your Timer History Events & Promotions Events & Promotions in June Open Detailed Calendar Some people form a joint account for one year with the condi Author Message TAGS: Hide Tags Manager Joined: 18 Dec 2012 Posts: 96 Location: India Concentration: General Management, Strategy GMAT 1: 660 Q49 V32 GMAT 2: 530 Q37 V25 GPA: 3.32 WE: Manufacturing and Production (Manufacturing) Followers: 1 Kudos [?]: 31 [1] , given: 34 Some people form a joint account for one year with the condi [#permalink] Show Tags 03 Sep 2013, 08:03 1 KUDOS 5 This post was BOOKMARKED 00:00 Difficulty: 75% (hard) Question Stats: 60% (04:38) correct 40% (03:08) wrong based on 92 sessions HideShow timer Statistics Some people form a joint account for one year with the condition that every month each member deposits an amount equal to the number of members in the account in that month. Also, the person who withdraws from the account before the end of the year get his/her amount at the end of the year. After 6 months, 1/4th of the people withdraw and 1/3rd of the remaining withdraw after 3 months. At the end of the year there is an amount of Rs. 4860 in the account before paying of the withdrawn amounts. Find out the number of people in the beginning of the year. A. 12 B. 24 C. 36 D. 48 E. 60 [Reveal] Spoiler: OA _________________ I'm telling this because you don't get it. You think you get it which is not the same as actually getting it. Get it? Last edited by Bunuel on 03 Sep 2013, 08:08, edited 1 time in total. Renamed the topic and edited the tags. Intern Joined: 04 Aug 2013 Posts: 9 Followers: 0 Kudos [?]: 0 [0], given: 7 Re: Some people form a joint account for one year with the condi [#permalink] Show Tags 03 Sep 2013, 18:41 Qoofi wrote: Some people form a joint account for one year with the condition that every month each member deposits an amount equal to the number of members in the account in that month. Also, the person who withdraws from the account before the end of the year get his/her amount at the end of the year. After 6 months, 1/4th of the people withdraw and 1/3rd of the remaining withdraw after 3 months. At the end of the year there is an amount of Rs. 4860 in the account before paying of the withdrawn amounts. Find out the number of people in the beginning of the year. A. 12 B. 24 C. 36 D. 48 E. 60 Need the solution, cant reach to B as the solution Manager Joined: 06 Jul 2013 Posts: 116 GMAT 1: 620 Q48 V28 GMAT 2: 700 Q50 V33 Followers: 0 Kudos [?]: 24 [1] , given: 42 Re: Some people form a joint account for one year with the condi [#permalink] Show Tags 03 Sep 2013, 20:42 1 KUDOS N people in the start. first 6 months there would 6.N.N money deposited. 1/4 members are gone so 3/4 left Then next 3 month 3.3N/4.3N/4 then 1/3 of remaining gone = 3N/42/3 = N/2 so money deposited 3.N/2.N/2 total = 6N^2+27/16N^2+3/4N^2 = 4860 solve for N = 24 Manager Joined: 18 Dec 2012 Posts: 96 Location: India Concentration: General Management, Strategy GMAT 1: 660 Q49 V32 GMAT 2: 530 Q37 V25 GPA: 3.32 WE: Manufacturing and Production (Manufacturing) Followers: 1 Kudos [?]: 31 [1] , given: 34 Re: Some people form a joint account for one year with the condi [#permalink] Show Tags 04 Sep 2013, 00:30 1 KUDOS Let x be the number of people in the beginning. Amount deposited for 6 months = 6xx = 6x^2 Number of people for the next 3 months = x -x/4 = 3x/4 Amount deposited for the next 3 months = 3 (3x/4)^2 Number of people for the last 3 months = 3x/4 - (1/3 * 3x/4) = x/2 Amount deposited for the last 3 months = 3* (x/2)^2 Total amount = 6x^2 + 27x^2/16 + 3x^2/4 = 4860 x= 24 (option B) _________________ I'm telling this because you don't get it. You think you get it which is not the same as actually getting it. Get it? GMAT Club Legend Joined: 09 Sep 2013 Posts: 14396 Followers: 604 Kudos [?]: 174 [0], given: 0 Re: Some people form a joint account for one year with the condi [#permalink] Show Tags 08 Nov 2014, 09:15 Hello from the GMAT Club BumpBot! Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos). Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email. _________________ Manager Joined: 22 Aug 2014 Posts: 195 Followers: 0 Kudos [?]: 10 [0], given: 49 Re: Some people form a joint account for one year with the condi [#permalink] Show Tags 14 Apr 2015, 05:37 Qoofi wrote: Let x be the number of people in the beginning. Amount deposited for 6 months = 6xx = 6x^2 Number of people for the next 3 months = x -x/4 = 3x/4 Amount deposited for the next 3 months = 3 * (3x/4)^2 Number of people for the last 3 months = 3x/4 - (1/3 * 3x/4) = x/2 Amount deposited for the last 3 months = 3* (x/2)^2 Total amount = 6x^2 + 27x^2/16 + 3x^2/4 = 4860 x= 24 (option B) Why are we multiplying things two times(^2)? Intern Joined: 01 Apr 2015 Posts: 9 Followers: 0 Kudos [?]: 6 [0], given: 7 Re: Some people form a joint account for one year with the condi [#permalink] Show Tags 15 Apr 2015, 01:00 ssriva2 wrote: Why are we multiplying things two times(^2)? Because at the end of each month, each person deposits an amount equal to the number of people. For example, if there are 24 people, each would deposit $24 (or whatever currency the question is asking), meaning a total of 2424 dollars is deposited. So if you start out with $$n$$ people: > After month 1: ($$n$$ x $$n$$) deposited = $$n^2$$ > After month 2: +$$n^2$$ deposited > After month 3: +$$n^2$$ deposited > After month 4: +$$n^2$$ deposited > After month 5: +$$n^2$$ deposited > After month 6: +$$n^2$$ deposited * Here, 1/4 of people leave and you are left with $$\frac{3}{4}n$$ people, each depositing $$\frac{3}{4}n$$ dollars > After month 7: +($$\frac{3}{4}n$$) x ($$\frac{3}{4}n$$) deposited = $$\frac{9}{16}n^2$$ > After month 8: +$$\frac{9}{16}n^2$$ deposited > After month 9: +$$\frac{9}{16}n^2$$ deposited Here, 1/3 of the remaining people leave and you are left with $$(\frac{2}{3})(\frac{3}{4}n)$$ people, each depositing $$(\frac{2}{3})(\frac{3}{4}n)$$ dollars ** > After month 10: + ($$\frac{2}{3})(\frac{3}{4}n$$) x $$(\frac{2}{3})(\frac{3}{4}n)$$ = $$\frac{1}{4}n^2$$ > After month 11: +$$\frac{1}{4}n^2$$ > After month 12: +$$\frac{1}{4}n^2$$ Put it all together and for the 12-month period, you get: $$6(n^2) + 3(\frac{9}{16}n^2) + 3 (\frac{1}{4})n^2 = 4860$$ Finally, solve to get: $$n=24$$ Answer: B GMAT Club Legend Joined: 09 Sep 2013 Posts: 14396 Followers: 604 Kudos [?]: 174 [0], given: 0 Re: Some people form a joint account for one year with the condi [#permalink] Show Tags 22 Jun 2016, 11:39 Hello from the GMAT Club BumpBot! Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos). Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email. _________________ Re: Some people form a joint account for one year with the condi [#permalink] 22 Jun 2016, 11:39 Similar topics Replies Last post Similar Topics: 1 Last year at an accounting firm, accountants made up 40% of the total 1 22 Feb 2017, 16:00 12 This year, x people won an Olympic medal for water competitions. One 7 16 Sep 2015, 07:16 5 In a joint family there are 3 couples. The ages (all in years) of the 3 06 Nov 2014, 20:56 21 At the end of year X, automobile installment credit accounte 7 11 Nov 2013, 13:31 1 John deposits$5000 in a savings account for 5 years 3 12 Jan 2012, 18:41 Display posts from previous: Sort by	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.2192656695842743, "perplexity": 3964.900422644305}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-13/segments/1490218188773.10/warc/CC-MAIN-20170322212948-00031-ip-10-233-31-227.ec2.internal.warc.gz"}
https://www.physicsforums.com/threads/wronskian-determinants-help.196298/	# Wronskian Determinants help 1. Nov 5, 2007 ### sapiental 1. The problem statement, all variables and given/known data Hi, could someone please confirm my results. I just put my answers because the procedure is so long. let me know if you get the same results. 1) Wronskian(e^x, e^-x, sinh(x)) = 0 2) Wronskian(cos(ln(x)), sin(ln(x)) = 1/x * [cos^2(ln(x)) + sin^2(ln(x))] = 1/x 2. Nov 5, 2007 ### Dick The one is super easy. sinh(x) is a linear combination of e^x and e^(-x). So 0. You don't even have to compute anything. And you are right on the second one as well. Have something to add? Similar Discussions: Wronskian Determinants help	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8394523859024048, "perplexity": 2764.4684211179483}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-40/segments/1474738660916.37/warc/CC-MAIN-20160924173740-00205-ip-10-143-35-109.ec2.internal.warc.gz"}
https://link.springer.com/chapter/10.1007/978-981-13-0520-7_3	# Networked Predictive Control Based on Linear Input-Output Model • Zhong-Hua Pang • Guo-Ping Liu • Donghua Zhou • Dehui Sun Chapter ## Abstract In this chapter, in order to compensate for random network-induced delays, packet disorders, and packet dropouts in the feedback and forward channels, a networked predictive control method is presented for networked linear systems based on an input-output difference equation model. In ideal situations, the resulting closed-loop networked system can achieve the same output tracking performance as that of the corresponding local control system where there exist no networks in the control loop. A stability condition is given for the closed-loop networked system with disturbances and modelling errors. Simulation and experimental results are given to illustrate the effectiveness of the proposed method. ## References 1. 1. Bara, G.I., Boutayeb, M.: Static output feedback stabilization with $$H_\infty$$ performance for linear discrete-time systems. IEEE Trans. Autom. Control 50(2), 250–254 (2005) 2. 2. Choi, Y., Cheong, J.: New expressions of $$2\times 2$$ block matrix inversion and their application. IEEE Trans. Autom. Control 54(11), 2648–2653 (2009) 3. 3. Dong, J., Yang, G.H.: Robust static output feedback control synthesis for linear continuous systems with polytopic uncertainties. Automatica 49(6), 1821–1829 (2013) 4. 4. Du, X., Yang, G.H.: New characterisations of positive realness and static output feedback control of discrete-time systems. Int. J. Control 82(8), 1485–1495 (2009) 5. 5. Ge, Y., Wang, J., Li, C.: Robust stability conditions for DMC controller with uncertain time delay. Int. J. Control Autom. Syst. 12(2), 241–250 (2014) 6. 6. Gupta, R.A., Chow, M.Y.: Networked control system: overview and research trends. IEEE Trans. Ind. Electron. 57(7), 2527–2535 (2010) 7. 7. Hespanha, J.P., Naghshtabrizi, P., Xu, Y.: A survey of recent results in networked control systems. Proc. IEEE 95(1), 138–162 (2007) 8. 8. Hu, W., Liu, G.P., Rees, D.: Networked predictive control over the Internet using round-trip delay measurement. IEEE Trans. Instrum. Meas. 57(10), 2231–2241 (2008) 9. 9. Irwin, G.W., Chen, J., McKernan, A.W.G.S., Scanlon, W.G.: Co-design of predictive controllers for wireless network control. IET Control Theory Appl. 4(2), 186–196 (2010) 10. 10. Liu, G.P., Mu, J.X., Rees, D., Chai, S.C.: Design and stability analysis of networked control systems with random communication time delay using the modified MPC. Int. J. Control 79(4), 288–297 (2006) 11. 11. Onat, A., Naskali, T., Parlakay, E., Mutluer, O.: Control over imperfect networks: model-based predictive networked control systems. IEEE Trans. Ind. Electron. 58(3), 905–913 (2011) 12. 12. Pang, Z.H., Liu, G.P., Zhou, D., Sun, D.: Design and performance analysis of networked predictive control systems based on input-output difference equation model. Int. J. Control Autom. Syst. 15(1), 416–426 (2017) 13. 13. Rahmani, B., Markazi, A.H.D., Nezhad, P.M.: Plant input-mapping-based predictive control of systems through band-limited networks. IET Control Theory Appl. 5(2), 341–350 (2011) 14. 14. Sun, X.M., Wu, D., Liu, G.P., Wang, W.: Input-to-state stability for networked predictive control with random delays in both feedback and forward channels. IEEE Trans. Ind. Electron. 61(7), 3519–3526 (2014) 15. 15. Tang, P.L., de Silva, C.W.: Compensation for transmission delays in an Ethernet-based control network using variable-horizon predictive control. IEEE Trans. Control Syst. Technol. 14(4), 707–718 (2006) 16. 16. Ulusoy, A., Gurbuz, O., Onat, A.: Wireless model-based predictive networked control system over cooperative wireless network. IEEE Trans. Ind. Inform. 7(1), 41–51 (2011) 17. 17. Zhang, D., Shi, P., Wang, Q.G., Yu, L.: Analysis and synthesis of networked control systems: a survey of recent advances and challenges. ISA Trans. 66, 376–392 (2017) 18. 18. Zhang, J., Xia, Y., Shi, P.: Design and stability analysis of networked predictive control systems. IEEE Trans. Control Syst. Technol. 21(4), 1495–1501 (2013) 19. 19. Zhang, L., Gao, H., Kaynak, O.: Network-induced constraints in networked control systems - a survey. IEEE Trans. Ind. Inform. 9(1), 403–416 (2013) 20. 20. Zhao, Y.B., Liu, G.P., Rees, D.: Design of a packet-based control framework for networked control systems. IEEE Trans. Control Syst. Technol. 17(4), 859–865 (2009) © Springer Nature Singapore Pte Ltd. 2019 ## Authors and Affiliations • Zhong-Hua Pang • 1 • Guo-Ping Liu • 2 • Donghua Zhou • 3 • Dehui Sun • 1 1. 1.North China University of TechnologyBeijingChina 2. 2.University of South WalesPontypriddUK 3. 3.Shandong University of Science and TechnologyQingdaoChina	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.501460075378418, "perplexity": 17815.60965780635}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-51/segments/1544376829997.74/warc/CC-MAIN-20181218225003-20181219011003-00388.warc.gz"}
http://etna.ricam.oeaw.ac.at/volumes/2001-2010/vol37/abstract.php?vol=37&pages=413-436	## Analysis of a non-standard finite element method based on boundary integral operators Clemens Hofreither, Ulrich Langer, and Clemens Pechstein ### Abstract We present and analyze a non-standard finite element method based on element-local boundary integral operators that permits polyhedral element shapes as well as meshes with hanging nodes. The method employs elementwise PDE-harmonic trial functions and can thus be interpreted as a local Trefftz method. The construction principle requires the explicit knowledge of the fundamental solution of the partial differential operator, but only locally, i.e., in every polyhedral element. This allows us to solve PDEs with elementwise constant coefficients. In this paper we consider the diffusion equation as a model problem, but the method can be generalized to convection-diffusion-reaction problems and to systems of PDEs such as the linear elasticity system and the time-harmonic Maxwell equations with elementwise constant coefficients. We provide a rigorous error analysis of the method under quite general assumptions on the geometric properties of the elements. Numerical results confirm our theoretical estimates. Full Text (PDF) [292 KB], BibTeX ### Key words Finite elements, boundary elements, BEM-based FEM, Trefftz methods, error estimates, polyhedral meshes. 65N30, 65N38	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9235100746154785, "perplexity": 684.5957679918787}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-51/segments/1575540527010.70/warc/CC-MAIN-20191210070602-20191210094602-00335.warc.gz"}
https://rd.springer.com/article/10.1007/s10618-015-0410-5	Data Mining and Knowledge Discovery , Volume 30, Issue 1, pp 226–242 # A computational approach inspired by simulated annealing to study the stability of protein interaction networks in cancer and neurological disorders • Kristina Ibáñez • María Guijarro • Gonzalo Pajares • Alfonso Valencia Open Access Article ## Abstract Molecular networks provide a powerful tool for the study of biomedical systems, in particular several studies have detected alterations of the network structure associated to disease states. Here we propose that diseases cannot only alter the structure of the network but also its stability. To evaluate network stability we have developed a new methodological framework. Our approach is an adaptation of the classical Deterministic Simulated Annealing algorithm to work with discrete states. Adjusted energy values are used to compare the network stability in disease and control states. The results show that cancer networks are less stable than the Alzheimer’s disease (AD) ones. These results can be interpreted in terms of our previous observations on cancer and AD inverse comorbidity, i.e. AD patients have lower than expected risk to suffer cancer. ## Keywords Simulated annealing Systems biology Gene expression Protein interaction networks Cancer Neurological disorders Inverse comorbidity ## 1 Introduction Neurological disorders and cancer are two current global health priorities. Interestingly, epidemiological evidence is mounting that patients with certain neurological disorders, including those suffering from Schizophrenia (SCZ) and Alzheimer’s disease (AD), have a lower than expected tendency to develop some forms of cancer (Behrens et al. 2009, 2012; Tabarés-Seisdedos and Rubenstein 2013; Tabarés-Seisdedos et al. 2011). Hence, we performed a systematic meta-analysis of gene expression in order to investigate the molecular mechanisms that might underlie such inverse comorbidity, identifying genes and pathways differentially expressed in neurological disorders and some types of cancer (Ibáñez et al. 2014). Interestingly, we found a common set of genes and biological processes that were apparently deregulated in opposing directions in cancers and neurological disorders. Here, we set out to broaden our understanding of the molecular basis underlying the differences between cancers and neurological conditions. As such, and given that the central dogma of molecular biology dictates that information flows from genes to proteins via RNA (Crick 1970), we integrated gene expression data with protein–protein interaction networks (PPINs) in order to study these differences in terms of network organization rather than at the level of individual genes. Gene expression data informs whether a gene that encodes a given protein is active or not. Yet proteins function in the context of their interactions with other proteins, interactions that are described in PPINs in which each protein represents a node in the network. In PPINs, it is assumed that proteins corresponding to genes that are not active (i.e.: unexpressed) will not interact with their potential partners. Therefore, the production of RNA by genes is commonly used as a proxy of the activity of the gene, and this is correlated with the activation of molecular systems within PPINs that underlie physiological and developmental processes. Indeed, in many cases, deregulation of gene expression provokes dramatic phenotypic changes, as occurs in several diseases (Kaern et al. 2005). Protein interaction maps have been used to study the molecular organization of cellular systems and the perturbations in them created by disease. PPINs reflect the functionality of interacting proteins and for example, the consequence of a single gene deletion in the yeast Saccharomyces cerevisiae would appear to depend on the position of the gene product within the PPIN (Jeong et al. 2001). Thus, the proteins most important for a cell’s survival are highly connected (Jeong et al. 2001; Wuchty and Almaas 2005) and altering them has profound effects on the PPIN. In terms of cancer, it is thought that cancer related proteins correspond to central hubs and that they are highly connected within networks (Jonsson and Bates 2006). Indeed, the genomic and network characteristics of genes mutated in cancer seem to confirm that these genes tend to encode central hubs within PPINs (Rambaldi et al. 2008). In addition, PPINs have been used as background layers when mapping gene expression data in order to gain information about the state of the nodes and their possible dynamics (Börnigen et al. 2013; Chuang et al. 2007; Hudson et al. 2009; Komurov and Ram 2010; Liu et al. 2013; Milanesi et al. 2009; Pujana et al. 2007; Schramm et al. 2010; Teschendorff and Severini 2010; Pel et al. 2013; West et al. 2012). For example, genes that are over expressed in lung cancer are more strongly connected than those that are suppressed or selected at random (Wachi et al. 2005). We hypothesize that PPINs related to cancer are more unstable than those based on neurological data. This may be because there are more active interactions between cancer related proteins and thus, a mutation or change in any of these would cause an important destabilization of the network. By contrast, proteins corresponding to genes affected in neurological disorders have less active connections and consequently, they are less susceptible to destabilization. In this context, we present an approach based on the combination of gene expression data and PPINs to study the relationship between cancers and neurological disorders. To achieve this we associate each protein (or node) in the network with a state that is directly related to the level of expression of the corresponding gene. The expression data used is derived from a large series of experiments carried out on cancer and neurological disorders in humans, information that makes the PPINs disease specific and that allows comparative studies to be performed. In terms of the computational methodology to study the differences between disease specific networks, we have found an appropriate equivalence in the Deterministic Simulated Annealing (DSA) algorithm proposed previously (Duda et al. 2007). The DSA algorithm was designed to find the optimal solution inspired by different biological or physical phenomena. The DSA is based on the shifting of metals from an unstable state as a liquid to a stable solid state, a process mediated by a decrease in the temperature of the material. These transformations can be simulated by the evolution of the states of interconnected network nodes that evolve until an optimal solution with minimal energy is reached. This evolution is controlled through an energy minimization process that determines the network’s stability as the energy decreases. Therefore, lower energies correspond to greater stability. Inspired by the DSA algorithm, we designed and implemented a new method to measure the stability of PPINS based on a defined energy function. In this approach the concept of stability differs from that in the original DSA, in which the network evolves towards states with different stabilities via temporal transitions or another equivalent value (Cruz García et al. 2011, 2002; Pajares and Cruz 2004; Sánchez-Lladó et al. 2011). The proposed approach used in this study computes energy based on existing interactions and it computes the energy difference between two states, such as disease and control samples. In this manner, the temporal aspect of the original DSA is reduced to the comparison between a reference and a new model. The reference state can be considered to be equivalent to the initial state and the new model as a single progressive step. Furthermore, any simulated annealing process (DSA or probabilistic) is driven by an optimization process in order to achieve stable states (minimum energy values). By contrast, since only one transition is considered in our approach, there is no optimization process involved and local minima energy are avoided. These substantial differences from the original DSA are introduced to make it possible to perform a large scale systematic comparison of networks associated to cancer, neurological disorders and normal controls for which the information available comes from experiments carried out at only one time point, representing a single state of these conditions. ## 2 Materials and methods ### 2.1 Materials The protein interaction and gene expression data used in this study were obtained from PPIN and Gene expression data sets. #### 2.1.1 The protein–protein interaction network (PPIN) We used the human PPIN from the protein interaction network analysis database (PINA, http://cbg.garvan.unsw.edu.au/pina/interactome.stat.do, version October 2011. Online Resource 1: Wu et al. 2009). PINA is an integrated platform of PPIN data that has been extracted from six different public databases: IntAct, MINT, BioGRID, DIP, HPRD, and MIPS/MPact. It includes self-interactions, interactions predicted by computational methods, and interactions between human proteins and proteins from other species. Moreover, it has recently been used in other similar studies (Xia et al. 2011; Laakso and Hautaniemi 2010). Besides the PINA network, we also used two additional PPINs in order to guarantee that a similar outcome was obtained: The Human Protein Reference Database (HPRD, http://www.hprd.org/download, version April 2010) that contains pairs of human protein interactions based on experimental evidence from the literature and that has been used in several studies (Teschendorff and Severini 2010; West et al. 2012); and the Human Integrated protein–protein interaction rEference (HIPPIE, http://cbdm.mdc-berlin.de/tools/hippie/download.php, version September 2014) that incorporates a human PPI dataset with a normalized scoring scheme, integrating data from HPRD, BioGRID, IntAct, MINT, Rual05, Lim06, Bell09, Stelzl05, DIP, BIND, Colland04, Lehner04, Albers05, MIPS, Venkatesan09, Kaltenbach07 and Nakayama02. We selected the interactions from these PPINs with a curated score above 0.73 in order to be confident that the pairs of proteins interact (Schaefer et al. 2012). #### 2.1.2 Gene expression data sets Measuring gene expression with microarrays is now a common molecular biology approach in biomedicine, making it possible to simultaneously measure the relative expression of thousands of genes under different experimental conditions (Current Topics in Computational Molecular Biology, 2002). Thousands of gene expression data sets are available in public databases, each containing a description of the corresponding biomedical origin of the sample, the analytic procedures followed and the experimental results in terms of expression (i.e.: the amount of RNA produced for each gene in the genome). Raw experimental gene expression data (CEL files) for Ovarian, Colon, Liver and Kidney datasets were downloaded from the Barcode human transcriptome repository (Gene Expression Barcode, http://barcode.luhs.org/), and for the SCZ and AD datasets they were downloaded from the NCBI GEO omnibus (GEO, http://www.ncbi.nlm.nih.gov/geo) and Stanley Medical Research Institute Online Genomics Database (SMRI, https://www.stanleygenomics.org: Online Resource 2). Importantly, each dataset corresponds to a collection of disease and control samples. For the analysis we filtered out the cases with too few disease/control cases (less than 9) and we only used those produced in the same platform (Affymetrix array GeneChip Human Genome U133 Plus 2.0), rendering information on 23,945 human genes. This technical platform has been widely used, and using the same platform on all data sets facilitates comparative studies and ameliorates potential experimental errors. ### 2.2 Methods In order to study the stability of the PPIN in cancer, neurological and normal samples, we implemented an original method inspired by the well-known DSA approach that was customized to study neighbor-energy (nE). In this case, stability describes a network state that is not significantly altered, even when fundamental properties have changed or perturbations have been introduced. From the biological point of view, network instability could reflect a situation where mutations in a key protein involved in many interactions will alter several associated biological processes. A filtered PPIN (Sect. 2.2.1), and preprocessed and normalized gene expression data (Sect. 2.2.3) for three different conditions (cancer, normal and neurological disorders), were the inputs for our approach (Sect. 2.2.4). A scheme of the workflow is presented in Fig. 1, where preprocessing and filtering are clearly represented as two separate modules. #### 2.2.1 Protein–protein interaction network filtering Data from the PINA network were filtered by requiring experimental evidence for PPIs, removing redundancy and self-interactions, as well as interactions involving proteins that were not from Homo sapiens. Thus, we only considered those interactions between proteins that were also detected in the Human Genome U133 Plus 2.0 microarray platform. The resulting filtered PINA network contains 10,650 proteins with 63,119 interactions. Each node denotes a protein encoded by a gene and each edge denotes an interaction between two proteins (Fig. 2a). #### 2.2.2 Sub-network related to the synaptic vesicle cycle A sub-network of proteins encoded by genes related to the synaptic vesicle cycle was analyzed, retrieving proteins in the synaptic vesicle (SV) cycle from the KEGG pathway (http://www.genome.jp/dbget-bin/www_bget?pathway:hsa04721, version September 2014). The number of genes involved in the SV cycle pathway are 63, and 50 out of 63 genes were detected in microarrays. The resulting sub-network contains 50 proteins and 3815 interactions. #### 2.2.3 Microarray gene expression preprocessing Handling microarrays requires the preprocessing of each individual microarray to estimate the expression of each gene in the array. Gene expression data from Ovarian, Colon, Liver and Kidney cancers, and from SCZ and AD samples, were normalized by frozen Robust Multiarray Analysis (fRMA: (McCall et al. 2012) from the R Affy package (Gautier et al. 2004). Background-corrected gene intensities were obtained by applying fRMA processes to each array individually, and accounting for probe variability, batch effects, probe effects, array-to-array variability and background noise. The samples were then processed using Barcode (McCall et al. 2012) in order to convert gene intensities into estimates of gene expression (Z-score, Fig. 2b). Additionally, gene intensities were mapped into a binary vector of “ones” and “zeros” that denote whether a gene was expressed (1, when the Z-score is higher than a threshold value: 4.98 by default) or not (0) in each sample (Fig. 2b and Supplementary Material: McCall et al. 2011; Zilliox and Irizarry 2007). These values were used in Eq. 1, in which it is not necessary to specify whether a gene is expressed or not. To compare the Z-score between these diseases, we normalized them using the pnorm function of the R stats package to calculate the normal distribution function of each Z-score. This normalization step is commonly employed to avoid values in a given range dominating other values. High Z-scores indicate intense gene expression, while small Z-scores correspond to weak expression. For expressed genes, defining S as the normalized Z-score, S = pnorm(Z-score), represents the probability of the gene being expressed. When the gene is not expressed, S = 1 $$-$$ pnorm(Z-score) indicates the probability of the gene not being expressed. These S values were used in Eq. 2. Hence, each state in the system would represent the significance (S) of the expression of each gene (Fig. 2b). In summary, for each disease we associated a binary value reflecting whether or the gene is expressed (one or zero, respectively), attributing a value and a significance to the expression each of the 10,650 genes in the network (Fig. 2b). #### 2.2.4 Adapted simulated annealing approach To study network stability we adopted an approach based on the SA concept, a probabilistic method that allows the global minimum of a generic cost function to be found (Kirkpatrick et al. 1983; Cerny 1985). This procedure reproduces the way the structure of a solid reaches its minimum energy configuration through cooling, becoming “frozen” at this minimum energy. A full description of the DSA is included in Online Resource 3 (Duda et al. 2007; Haykin 1994), which also follows a physical analogy based on a set of interconnected nodes, each one with its associated state. During the cooling process forces between interconnected nodes act on the structure, which evolves until each node reaches a stable state. Thus, the nodes interacting with other nodes within the system influence one another with a defined weight. Our algorithm is inspired on the definition of a nE function that measures the stability of the network, as well as on the general deterministic approach whereby a lower nE is related to greater stability. In our case, using a nE function that decreases in function of the interactions or over time does not make sense given the characteristics of the biological problem. Indeed, our approach does not evolve through iterations or time and thus, this part of the algorithm was not considered. Our system is represented by a PPIN in which nodes represent proteins associated to the expression of the corresponding gene ($$S_{i}$$ describes the significance (S) of a gene $$i$$ being expressed or not). The DSA approach is applied to estimate the dynamic structures in the PPIN (Fig. 2c), where $$S_{i}$$ represents the state of the node in the original DSA approach and the edges reflect the interactions existing between proteins. Each $$W_{ij}$$ represents the weight required (Eq. 1), where $$W_{ij}$$ is inversely associated to the existence of the interaction between two proteins. If the two genes $$i$$ and $$j$$ are both expressed, then the two corresponding proteins can interact ($$W_{ij}$$ value $$-1$$). The value of $$W_{ij}$$ will be +1 if the interaction is not possible because one of the two genes is not expressed. \begin{aligned} W_{ij} =\left\{ {\begin{array}{l} -1\quad if\; i\, expressed,\, j\, expressed \\ +1\quad if\; i\, or\, j\, not\, expressed \\ +1\quad if\; i\, not\,expressed,\, j\, not\, expressed \\ \end{array}} \right. \end{aligned} (1) Consistent with the main idea of the SA algorithm, the local_nE is defined as the sum of the energy from all the nodes connected to a given node $$i$$. This influence is calculated by multiplying the expression of each gene (normalized value of expression, S) by the associated weights of the connected nodes ($$W_{ij})$$, as summarized in (2). \begin{aligned} local\_nE(i)=-\sum _j {W_{ij} S_i S_j} \end{aligned} (2) According to the definition in Eq. 2, the local_nE is maximal when $$W_{ij} S_i S_j$$ is at its minimum, representing active connections between nodes of expressed genes (Eq. 1, case 1) and indicating that any alteration in this node will destabilize the network. The value of the local_nE decreases for those node connections that involve at least one gene that is not expressed in that condition, reflecting the fact that the interactions cannot take place (Eq. 1, cases 2 and 3). In these situations, the local_nE achieves its minimum values indicating network stability. The local_nE function measures the stability of a single protein or node $$i$$ in function of its neighborhood, i.e. only with respect to the directly interacting partners and not within the entire network. The global nE value (Eq. 3), and therefore the stability of the entire network, will be a consequence of the equilibrium between interactions among active (corresponding to the expressed genes) and inactive nodes (corresponding to non-expressed genes). \begin{aligned} nE=\sum _i {local\_nE(i)} \end{aligned} (3) #### 2.2.5 Computation of network robustness To assess the robustness of the system, we analyzed how the network structure changes as nodes are removed in accordance with previously defined procedures (Iyer et al. 2013). Changes in the network structure are evaluated in terms of the size of the largest connected component of the network. Networks in which the largest component decreases faster than that of the original network are considered to be less robust to perturbations. Thus, nodes were removed in decreasing order of their local_nE scores (Eq. 2), removing the proteins (or nodes) with higher local_nE values first (i.e.: those with more active connections) and those with the lowest local_nE scores last (i.e.: those less connected to their neighbors) . Network robustness was measured through the R-index in Eq. 4, where $${\upalpha }$$ corresponds to the size of the largest connected component within the network after a node is removed. \begin{aligned} R = \frac{1}{N} \sum _{i=1}^N {\alpha (i/N)} \end{aligned} (4) We computed the R-index for cancer and normal control samples at each step after the removal of nodes in function of the order of local_nE scores. ## 3 Results Using this new approach, we have analyzed four gene expression datasets for cancer (Ovarian, Colon, Liver and Kidney), four data sets for SCZ and five for AD (Online Resource 1), each having sufficient disease and control samples, and fulfilling our quality control criteria (see Sect. 2). For each disease and data set, PPIN stability was assessed in both the disease and control samples. In other words, we simulated a weighted interaction network for each sample, mapping S into the PPIN, directly applying the proposed algorithm and obtaining a nE value. The distribution of the nE values for the normal (N) and disease (C) conditions were then studied (Fig. 3) and a global nE was obtained for each disease. ### 3.1 Increased neighbor-energy in cancer tissue The cancer PPINs present characteristic instability, reflected by higher nE values than their normal control samples (Fig. 3a). A Mann–Whitney (Wilcoxon-rank) test was used to evaluate whether the medians of a test variable differed significantly between the normal and cancer samples, which proved to be the case for each tissue (represented below the x-axis). Indeed, very significant Wilcoxon test p values were obtained for the Ovarian, Colon, Liver and Kidney data sets (3.11e$$-$$04, 2.62e$$-$$03, 2.10e$$-$$05 and 2.33e$$-$$08, respectively), indicative of meaningful and important differences between the nE distributions in cancer and normal samples, with cancer samples being considerably less stable than their normal counterparts. ### 3.2 Decreased neighbor-energy in tissues from neurological disorders Significant differences in nE distributions were evident when AD (C) and normal (N) samples were compared (Fig. 3b), and significant Wilcoxon p values were obtained for the nE distribution in virtually all of the AD studies. AD samples had smaller nE values than the normal samples, reflecting increased stability (decreased instability) in the AD network. By contrast, we only observed relevant differences between the nE distributions of the normal and disease states for one of the four SCZ data sets available (Fig. 3c). This discrepancy between the different SCZ networks suggests that further studies are required for this condition and the underlying cause is unlikely to be revealed until new, high quality experimental datasets become available. Similar results were obtained when networks other than PINA networks were used, including a smaller HPRD network (Online Resource 4) and a larger HIPPIE one (Online Resource 5). It is important to clarify whether these differences are the product of general differences in expression between cancer, normal and neurological disease tissues. However, the normalized expression data (Fig. 4) indicated that there was no difference between the global levels of normalized expression in this study. ### 3.3 Consistency of the results In order to assess the consistency of the results we analyzed sub-networks obtained by randomly sampling the complete network. Accordingly, 86 % of the sub-networks containing 10 % of the proteins of the original PINA network produced similar results to the complete network. In other words, not only was there significant instability in the overall network but most of the regions of the network conformed to this behavior, with only a few of them behaving distinctly (Online Resource 6 which includes the nE scores for the first one hundred random sub-samples). ### 3.4 Increased neighbor-energy in cancer evolution To further study the network instability in cancer, we assessed whether tumor progression might be related with increased instability. Indeed, the initial results showed a significant increase in network instability when the datasets obtained at different stages of tumor progression were compared (Fig. 5). ### 3.5 Network stability towards perturbations Stability has previously been described as a relatively invariant network state when perturbations are introduced. Thus, it is necessary to perform additional experiments to show that our definition of network stability measured through the nE score correlates well with this classical definition of robustness. Removing nodes from a network and then studying the evolution of the network’s connectivity provides a natural model to study the robustness of networked systems (Iyer et al. 2013; Callaway et al. 2000; Cohen et al. 2000). Accordingly, the R-index can be used to quantify network robustness (see Sect. 2.2.5). The successive removal of nodes according to their local_nE score produced a significant difference between the perturbation robustness in cancer and normal samples (Fig. 6a), and in AD and normal samples (Fig. 6b). When nodes were removed in a descending order of local_nE scores, greater robustness was evident in normal control networks (R-index = 0.52) than in cancer networks (R-index = 0.33: Fig. 6a). By contrast, AD networks are more robust (R-index = 0.50) than their corresponding normal control networks (R-index = 0.39: Fig. 6b). Hence, the definition of the nE score appears to be closely associated to network stability and as such, with the network’s robustness to perturbation. ### 3.6 Decreased instability in biological pathways implicated in Alzheimer’s disease We analyzed the decreased network instability observed for AD samples in more detail and in particular, we investigated the possible role of the proteins implicated in vesicle trafficking at synapses. Communication between neurons is mediated by the release of neurotransmitter from SVs and the expression of a group of genes involved in SV trafficking is reduced in brain tissues from AD cases. Indeed, the loss of synapses has been correlated with cognitive decline in AD and a malfunction of SV trafficking could be implicated in disrupting neuronal circuits in AD (Yao et al. 2003). As for the complete PPIN, there was a consistent decrease in instability in the SV related sub-network of proteins from AD samples (Online Resource 7a). The difference in the nE score suggests that important hubs within the network are expressed and regulated in opposite directions in AD and normal samples. Indeed, nine genes related to endocytosis were expressed in opposite manners in normal and AD samples: KIT, CLTA, CLTB, AP2M1, AP2S1, AP2B1, HLA-B1, AP2A2, and RAB11FIB2. Three genes associated with SV trafficking (SYP, STX1A and UNC13B) were inversely expressed in both conditions and they were highly connected in the protein network (hubs). In particular syntaxin 1A (STX1A) is known to regulate the exocytosis of SVs and neurotransmitter release (Bennett and Scheller 1993; Greengard et al. 1993; Hosaka et al. 1999). There was a clear trend towards reduced STX1A expression in all AD samples, which had a lower nE score than in normal control samples. Indeed, when the STX1A gene was not expressed (in blue) nor were its neighbors and conversely, when the STX1A gene was expressed (in red) so were most of its neighbors (Online Resources 7b and 7c). Accordingly, the stability of a particular sub-network relevant to a neurological disease under study is affected in the same way as the stability of the entire network. ## 4 Discussion In this work we have designed an approach inspired on SA, representing PPINs as systems of nodes that are dynamically updated towards a global state of stability. Our strategy is based on the definition of a neighbor-energy function that measures the stability of the network in the general deterministic approach, where nE indicates network stability, and it can be interpreted in terms of resistance to alterations and perturbations. In this study, we analyzed a large set of experimental data on gene expression and various PPINs. The first significant finding of this study is that networks containing information about expression in four human cancers (Ovarian, Colon, Kidney and Liver) are less stable than the control networks of normal samples. Moreover, this instability in the network seems to increase as these cancers evolve, at least in the tumor progression data sets analyzed. The approach employed is based on the analyses of samples in different conditions and it does not include temporal evolution per se. Thus, the results obtained by analyzing the temporal progression of tumors can be taken as an indication of network evolution towards a less stable state and a way of reconciling our methodology with the standard SA applications. The randomness or disorder in the local flux distribution surrounding any given node in the network $$i$$ has been quantified (West et al. 2012), showing that cancer is characterized by an increase in network entropy. This observation could be considered as independent confirmation of our general conclusion. Indeed, when gene expression data was previously integrated with a PPIN for six cancer tissues (Teschendorff and Severini 2010), an increase in network entropy was again seen to be associated to cancer based on a fluctuation theorem of dynamic systems theory. At the biological level cancer has been associated with a general destabilization of cellular processes related to the organization of the genome, its replication and repair (Murga and Fernández-Capetillo 2007). A conceptual framework explains how mutations in genes that control genetic stability are selected during tumor progression (Loeb 2011; Negrini et al. 2010; Solé et al. 2014; Wadhwa et al. 2013). Therefore, our observation of network instability in cancers fits well with current ideas in this field. Technically, our approach offers important advantages. First, raw gene expression data sets are divergent and independent, which represents an important difference. Additionally, we use a high quality filtered and curated PPIN, which while having practically the same number of total nodes it is less connected than those used in earlier studies. To deal with our biological problem we need to consider both the state of the nodes as well as the strength of the connections between them. This is possible with methods where these two important issues are considered, such as DSA, one of the generic means to resolve the optimization problem (Kirkpatrick et al. 1983). Our second important finding is that the AD network is more stable than its control normal network, with a significant increase in the nE of the corresponding networks. This is an interesting behavior that contrasts with that of cancers, and as far as we know is detected here for the first time. One possible interpretation of these results would be that cancer implies a general deregulation of cell growth through the hyperactivation of certain pathways, resulting in a destabilization of their interactions, while AD and other neurological disorders imply the stabilization of biological processes and network interactions, and their general slowing down. The striking contrast in the behavior of cancer and AD networks, from less to more stable networks, should be considered in the context of the observed “inverse comorbidity” of these two groups of diseases. A substantial number of epidemiological studies have shown that there is an inverse relationship between cancer and several central nervous system diseases, including AD. In other words, patients with AD tend to less frequently suffer some types of cancer (Tabarés-Seisdedos and Rubenstein 2013; for a complete meta-study of the available epidemiological studies see Catalá-López et al. 2013). Finally, given the importance of the diseases discussed in this work, it is necessary to make these results accessible for future experimental analysis. In this sense, an initial study of the molecular basis of this inverse comorbidity identified sets of genes expressed weakly in AD and strongly in cancers (Ibáñez et al. 2014). The new methodological approach developed here represents a further advance with respect to that initial approximation, where genes are not considered as independent units but rather as part of a connected network. This approach could be used as a classifier to distinguish cancer and normal samples. Another possibility will be to cluster the results of this procedure in order to extract specific proteins for which additional experimental information could be available, or could be tracked in direct experiments. Furthermore, this scheme could be also applied to any network system where the elements are characterized by a state $$\hbox {S}_{\mathrm{i}}$$ and their interactions associated to a weight $$\hbox {W}_{\mathrm{ij}}$$. In a biological context there are numerous systems with these characteristics, such as protein interaction and gene control networks. In the future, the application of clustering techniques to disease networks, such as Self Organizing Maps (SOM), will render information not on single genes but on clusters of collaborating genes, moving towards the study of the molecular causes of comorbidity to the level of systems biology. ## Notes ### Acknowledgments This work was supported by an Obra Social la Caixa grant (to K. I.) and Grant BIO2012-40205. We thank Clara Higuera, Anaïs Baudot, Daniel Rico and the reviewers for helpful reading, advice and comments. ## Supplementary material 10618_2015_410_MOESM1_ESM.pdf (5 mb) Online Resource 1 PINA dataset 5.02MB 10618_2015_410_MOESM2_ESM.pdf (93 kb) Online Resource 2Gene expression data sets used in the work 93.4KB 10618_2015_410_MOESM3_ESM.pdf (130 kb) Online Resource 3 Description of the Deterministic Simulated Annealing algorithm 129KB 10618_2015_410_MOESM4_ESM.pdf (252 kb) Online Resource 4 The nE distribution mapping all the genes in the HPRD network in the: (a) normal (N) and cancer (C) states (Ovarian, Colon, Liver and Kidney); (b) Normal (N) and AD (C); (c) Normal (N) and SCZ disease (C) state. The Wilcoxon-rank p-value is indicated below the x-axis 251KB 10618_2015_410_MOESM5_ESM.pdf (256 kb) Online Resource 5 The nE distribution mapping all the genes in the HIPPIE network in the: (a) normal (N) and cancer (C) states (Ovarian, Colon, Liver and Kidney); (b) Normal (N) and AD (C); (c) Normal (N) and SCZ disease (C) state. The Wilcoxon-rank p-value is indicated below the x-axis 255KB 10618_2015_410_MOESM6_ESM.pdf (1.4 mb) Online Resource 6 The nE distribution mapping all the genes in 100 random sub-sample networks in the normal (N) and cancer (C) conditions, sorted by increasing p-values, from left to right and from the top to the bottom. In red, cells with non-significant differences in the nE scores between the N and C conditions are shown, representing 14% of the random sub-networks 1.37MB 10618_2015_410_MOESM7_ESM.pdf (7.4 mb) Online Resource 7 Study of a particular pathway associated with the synaptic vesicle cycle. (a) The nE distribution mapping all the genes in the normal (N) and disease (C) states in AD into the sub-network created from proteins involved in the synaptic vesicle cycle. The Wilcoxon-rank p-value is indicated below the x-axis. (b) Protein-protein interaction sub-networks created from proteins involved in the synaptic vesicle cycle in the disease and (c) in the normal states for AD. Blue nodes represent non-expressed gene products, red nodes expressed gene products, red edges represent interactions between proteins in which both genes are expressed and gray edges represent other combinations. The red clouds contain the STX1A protein as well as all of its interacting partners 7.42MB ## References 1. Behrens MI, Lendon C, Roe CM (2009) A common biological mechanism in cancer and Alzheimer’s disease? Curr Alzheimer Res 6(3):196–204 2. 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Nat Methods 4(11):911–913. doi:	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 2, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7859874367713928, "perplexity": 4321.097851247689}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-34/segments/1534221208750.9/warc/CC-MAIN-20180814081835-20180814101835-00093.warc.gz"}
http://www.boundaryvalueproblems.com/content/2014/1/29	Research # On solvability of a nonlocal problem for the Laplace equation with the fractional-order boundary operator Moldir A Muratbekova*, Kanat M Shinaliyev and Batirkhan K Turmetov Author Affiliations Department of Mathematics, Akhmet Yasawi International Kazakh-Turkish University, B. Sattarkhanov Street 29, Turkistan, 161200, Kazakhstan For all author emails, please log on. Boundary Value Problems 2014, 2014:29 doi:10.1186/1687-2770-2014-29 Received: 15 August 2013 Accepted: 9 January 2014 Published: 30 January 2014 This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. ### Abstract In the present work, we study properties of some integro-differential operators of the Hadamard-Marchaud type in the class of harmonic functions. As an application of these properties, we consider the question of the solvability of a nonlocal boundary value problem for the Laplace equation in the unit ball. MSC: 35J05, 35J25, 26A33. ##### Keywords: Hadamard-Marchaud operator; fractional derivative; nonlocal problem ### 1 Introduction Let be the unit ball, . A paradigm in the theory of elliptic partial differential equations and harmonic functions is the Laplace equation (1) If we prescribe the values of the solution at the boundary Ω of Ω, then we can solve equation (1) uniquely. Of course, one can consider many other boundary conditions such as Neumann’s boundary conditions. In some applied problems of hydrodynamics [1], it is necessary to prescribe the value of a fractional derivative of the solution on the boundary. Fractional differential equations and boundary value problems involving fractional derivatives appear in many applied problems ranging from the spring-pot model [2] to geology [3] or from nonlinear circuits [4] to alternative models to differential equations [5]. Hence, in this paper we study the Laplace equation concentrating on some conditions on the boundary involving derivatives of fractional order. Note that numerous works of authors [6-13] were dedicated to the research questions of the solvability of boundary value problems for partial differential equations with boundary operators of high (whole and fractional) order. In the paper of A.N. Tikhonov [14] boundary value problems with boundary conditions containing derivatives of higher order have been investigated for the heat equation. Research questions as regards the solvability of similar problems for higher-order equations with boundary operators of whole and fractional order were carried out in [15,16]. Later in [17], these results were generalized for partial differential equations of fractional order. In [18-20] questions about the solvability of boundary value problems with boundary operators of high order were studied for the Laplace equation. In the studies of these authors the exact conditions for the solvability have been established and the integral representations of solutions of the studied problems have been found. The cycle of studies by the authors [21-26] is devoted to the study of the existence and smoothness of solutions of boundary value problems for the second-order elliptic equations with boundary operators of fractional order. In the paper mentioned above local boundary value problems with boundary operators of fractional order in the Riemann-Liouville or Caputo sense are studied. In this paper we study nonlocal problems with boundary operators of fractional-order derivatives of Hadamard type. Definitions of Hadamard operators, a statement of the main problems, and the history of the questions on this topic are in Section 3. The organization of this paper is as follows. In Section 2, we present the operators of integration and differentiation in the Hadamard sense and some modifications. In the third section we provide a formulation of the basic problem of this paper and some historical information as regards nonlocal boundary value problems. In the fourth section we study the properties of integral and differential Hadamard-Marchaud operators in the class of harmonic functions in the ball. In Section 5 we provide some auxiliary propositions. Finally, Section 6 is devoted to the study of the fundamental problem, where we formulate and prove the main statement of the paper. ### 2 Definition of Hadamard operators of integration and differentiation and some modifications In this section, we give a statement on the operators of fractional differentiation in the sense of Hadamard, Hadamard-Marchaud, and their modifications. For any positive α, fractional integrals and derivatives of the order α in the sense of Hadamard are defined by the following formulas [27]: (2) (3) where is the Dirac operator, is the integral part of α. If , then, in the class of sufficiently ‘good’ functions, operator (3) can be reduced to the following form [27]: (4) This operator is said to be the differentiation operator of order α in the sense of Hadamard-Marchaud. In [28], the following modification of the Hadamard-Marchaud operator was considered: (5) In [18], in the class of harmonic functions in a ball, the properties and applications of the operators in the form of (6) are considered. Here , , , and is a differential operator in the form of . Let be a harmonic function in the domain Ω, and let , be arbitrary real numbers. Let us consider a modification of the Bavrin operator (6). Introduce the operators If , , then we obtain the Bavrin operator . ### 3 Statement of the problem Let , , , be continuous mappings, and let be continuous functions satisfying the condition (7) We assume that the series (7) converges uniformly on Ω. Further, let , , and , i.e.α and β are not equal to zero simultaneously. Consider the following boundary value problem: (8) (9) where . A harmonic function from the class , such that and condition (9) is realized in the classical sense, will be called a solution of problem (8)-(9). The above-mentioned problem is a simple generalization of Bitsadze-Samarskii’s nonlocal problem [29]. For convenience of the reader, we formulate the Bitsadze-Samarskii problem. Let D be a finite simply-connected domain of the plane of complex variables with the smooth boundary , and let be a closed simple smooth curve lying in D. We denote by , , a diffeomorphism between S and . Formulation of the problem: We are to find a harmonic function in D, which is continuous in and satisfies the boundary condition where is a given function. Similar problems with operators of integer order were considered in [30-32], and for operators of fractional order with fractional-order derivatives in the sense of Riemann-Liouville and Caputo in [33-41]. It should also be noted that some questions of solvability of nonlocal problems for fractional-order equations in the one-dimensional case were studied in [42-44]. ### 4 Properties of operators and In this section, we study some properties of the operators and in the class of harmonic functions. Further, for convenience, we shall take everywhere . Lemma 1Let, , andbe a homogeneous harmonic polynomial of the power. Then the following equalities are correct: (10) (11) Proof Let . Then, using homogeneity of the polynomial , we obtain The value of the last integral can easily be calculated with the help of the change of variables . In fact, The equality (10) is proved. Further, note that the relation (12) holds for the operator . Now, let us study actions of the operator to the functions . Using the definition of and the homogeneity of , we have Denoting and integrating by parts, we get After the change of variables , as in the proof of equality (10), we easily obtain which implies . Further, taking into account fulfilling of equality (12), we obtain in the general case for : The lemma is proved. □ Lemma 2Let, , andbe a harmonic function in the ball Ω. Then the functionsandare also harmonic in Ω. Proof Let be a harmonic function in the ball Ω. Then it is known [45] that the function is represented in the form of the series (13) where is a complete system of homogeneous harmonic polynomials of power k, and are coefficients of the expansion (13). Applying formally the operator to the series (13) and taking into account equality (11), we obtain (14) Now let us check convergence of the series (13) and (14). The following asymptotical estimate is valid for : Moreover, the series (13) converges absolutely and uniformly by x at , hence, for any and any , the equalities hold. Since , we have for and Therefore, the series (14) converges absolutely and uniformly by x at , where , , and its sum is a harmonic function. By virtue of the arbitrariness of and , the function is defined in the whole ball Ω. Let us study the function . Applying formally the operator to the series (13), taking into account equality (10), we obtain Convergence of this series can be checked as in the case of series (14), and that is why is a harmonic function in the ball Ω. The lemma is proved. □ Now we show that the function can be represented in terms of the function . Lemma 3Let, , andbe a harmonic function in the domain Ω. Then for anythe equality is valid. Proof Let . Represent a harmonic function in the form of the series (13) and transform it to the form of (15) Further, taking into account equalities (10)-(11), and the absolute and uniform convergence of the series (15) by x at , it can be reduced to the form of The lemma is proved. □ One can similarly prove the following lemma. Lemma 4Let, , andbe a harmonic function in the domain Ω. Then for anythe equality (16) is valid. Lemma 5Let, , andbe a harmonic function in the domain Ω. Then the following equalities hold: Proof Let . Applying the operator to the function , we obtain By virtue of Lemma 3, the value of the last integral is equal to , i.e.. To prove the second equality, apply the operator to the function . We get Then, in the general case, The lemma is proved. □ ### 5 Some auxiliary propositions Let and satisfy the conditions from Section 2. Consider the following problem in the domain Ω: (17) (18) where , , and , i.e.α and β are not equal to zero simultaneously, . A harmonic function from the class , satisfying condition (18) in the classical case, will be called a solution of problem (17)-(18). It should be noted that problem (17)-(18) was investigated for the case of in [30]. Let us investigate uniqueness for the solution of problem (17)-(18). The following statement holds. Lemma 6Let, , , , be continuous functions satisfying the condition (19) and let a solution of problem (17)-(18) exist. Then: (1) If (20) then the solution of problem (17)-(18) is unique. (2) If (21) then the solution of problem (17)-(18) is unique up to a constant summand. Proof Let be the solution of problem (17)-(18) at . Denote , . Then if , then, by virtue of the maximum principle for harmonic functions [46], the inequality holds for any . The boundary condition (18) at implies Further, since , , , then , and for any , . Therefore . Hence, If now condition (19) is realized , then , and we obtain from this the contradiction . Hence, if condition (19) holds, it is necessary that . Since , substituting the function into the boundary condition (18), for we have The last equality is equivalent to the equality We obtain from this the result that either or . Thus, if conditions (19) and (20) are fulfilled, we obtain , i.e.. If the conditions (21) are fulfilled, then any constant is a solution of the homogeneous problem (17)-(18). In fact, substituting into equation (18), we obtain The lemma is proved. □ Now investigate existence of a solution of problem (17)-(18). Let and let be the Poisson kernel of the Dirichlet problem, and the area of the unit sphere. Introduce the function (22) and consider the equation (23) The following statement holds. Lemma 7Let, , , be continuous functions satisfying the condition (19). Then: (1) If the condition (20) is realized, then problem (17)-(18) is uniquely solvable at any. (2) If the condition (21) is realized, then problem (17)-(18) is solvable if the following condition is realized: (24) where the functionis a solution of equation (23), moreover the number of independent solutions of this equation under these conditions is equal to 1. Proof Since is a harmonic function, a solution of problem (17)-(18) can be found in the form of the Poisson integral where is an unknown function. Substituting this function into the boundary condition (18), we obtain the integral equation with respect to the unknown function , (25) Designate Then equation (25) can be rewritten in the form of (26) To investigate the solvability of the integral equation (26), we study the properties of the kernel . We show that is a continuous function on . In fact, since , we obtain for all , and therefore the function is continuous on . Further, the function has an integrable singularity, and that is why the function is continuous on . Then by virtue of the uniform convergence of the series , the kernel is also a continuous function on . Hence, one can apply Fredholm theory to equation (26). Since in the case of and fulfillment of the condition (20), the solution of problem (17)-(18) can only be , for the integral equation (26) has only a trivial solution. Hence, for any the solution of equation (26) exists, is unique, and belongs to the class . Using this solution, we construct the function which will satisfy all the conditions of problem (17)-(18). If the condition (21) is valid, then satisfies the condition (18) at , i.e. the corresponding homogeneous equation (26) has the nonzero solution . Then the adjoint homogeneous equation has also a nonzero solution, and that is why in this case fulfillment of the condition (24) is necessary and sufficient for solvability of problem (17)-(18). The lemma is proved. □ ### 6 Study of the basic problem We now formulate the basic statement. Theorem 1Let, , , , , , be continuous functions satisfying the condition (19). Then: (1) If the condition (20) is fulfilled, then problem (8)-(9) is uniquely solvable at any. (2) If the condition (21) is fulfilled, then the condition (24) is necessary and sufficient for solvability of problem (8)-(9) where the functionis a solution of equation (23). If a solution of the problem exists, then it is unique up to the constant summand. (3) If a solution of problem (8)-(9) exists, then it is represented in the form of, whereis a solution of problem (17)-(18). Proof (1) Let a solution of problem (8)-(9) exist. Apply to this function the operator and denote . Take the problem which the function satisfies. Since by Lemma 2, in the case of harmonicity of the function , the function is also harmonic in Ω, and the function is harmonic. Further, since according to Lemma 5 the equality holds, the boundary condition of problem (8)-(9), with respect to the function will be rewritten in the form of In addition, since , we have . Thus, if is a solution of problem (8)-(9), then the function will be a solution of problem (17)-(18). Now, let the conditions (19) and (20) be realized. Then by Lemmas 6 and 7, for any the solution of problem (17)-(18) exists, is unique, and designate , . Then we have by Lemma 5 in Ω, and therefore we get . Harmonicity of the function follows from Lemma 2, and fulfillment of the conditions (9) can be checked immediately: The first statement of the theorem is proved. (2) Let now the condition (21) be fulfilled, and let the solution of problem (8)-(9) exist. Consider the function . As in the first case, we show that the function satisfies the conditions of problem (17)-(18). Then according to Lemma 7, fulfillment of the condition (24) is necessary. Thus, we prove the necessity of the condition (24) at fulfillment of the equality (21). We show that if the equality (21) is fulfilled, then the condition (24) is also sufficient for the existence of the solution of problem (8)-(9). In fact, if the conditions (21) and (24) are realized, a solution of problem (17)-(18) exists, is unique up to constant summand, and . Then, similarly to the proof of the first statement of the theorem, the function satisfies all the conditions of problem (8)-(9). The theorem is proved. □ Remark 1 One can show that in the case of , the corresponding homogeneous problem (8)-(9) has nontrivial solutions. Example 1 Let , , , and , . Further, let be a homogeneous harmonic polynomial of the power k. By virtue of the equality (11), we have . Then and Hence, for the harmonic polynomial will be the solution of the homogeneous problem (8)-(9). If δ is a number close to zero, then we have . If the dimension of the space , then the number of these polynomials is equal to [47]. ### Competing interests The authors declare that they have no competing interests. ### Authors’ contributions All authors completed the paper together. All authors read and approved the final manuscript. ### Acknowledgements This work has been supported by the MON Republic of Kazakhstan under Research Grant No. 0713/GF. ### References 1. Serbina, LI: A model of substance transfer in fractal media. Math. Model.. 15, 17–28 (2003) 2. 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Bitsadze, AV: Uravneniya mathematicheskoi fiziki, Nauka, Moscow (1982)	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9717372059822083, "perplexity": 886.2158503376517}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-52/segments/1418802771716.117/warc/CC-MAIN-20141217075251-00148-ip-10-231-17-201.ec2.internal.warc.gz"}
http://www.aimsciences.org/journal/1551-0018/2015/12/5	# American Institute of Mathematical Sciences ISSN: 1551-0018 eISSN: 1547-1063 All Issues ## Mathematical Biosciences & Engineering 2015 , Volume 12 , Issue 5 Select all articles Export/Reference: 2015, 12(5): 907-915 doi: 10.3934/mbe.2015.12.907 +[Abstract](369) +[PDF](1005.2KB) Abstract: This paper presents a mathematical model of heat transfer in a prevascular breast tumor. The model uses the steady state temperature of the breast at the skin surface to determine whether there is an underlying tumor and if so, verifies whether the tumor is growing or dormant. The model is governed by the Pennes equations and we present numerical simulations for versions of the model in two and three dimensions. 2015, 12(5): 917-936 doi: 10.3934/mbe.2015.12.917 +[Abstract](411) +[PDF](1013.6KB) Abstract: In this study, we consider a model of T cell homeostasis based on the Smith-Martin model. This nonlinear model is structured by age and CD44 expression. First, we establish the mathematical well-posedness of the model system. Next, we prove the theoretical identifiability regarding the up-regulation of CD44, the proliferation time phase and the rate of entry into division, by using the experimental data. Finally, we compare two versions of the Smith-Martin model and we identify which model fits the experimental data best. 2015, 12(5): 937-964 doi: 10.3934/mbe.2015.12.937 +[Abstract](442) +[PDF](639.5KB) Abstract: We consider an in-host model for HIV-1 infection dynamics developed and validated with patient data in earlier work [7]. We revisit the earlier model in light of progress over the last several years in understanding HIV-1 progression in humans. We then consider statistical models to describe the data and use these with residual plots in generalized least squares problems to develop accurate descriptions of the proper weights for the data. We use recent parameter subset selection techniques [5,6] to investigate the impact of estimated parameters on the corresponding selection scores. Bootstrapping and asymptotic theory are compared in the context of confidence intervals for the resulting parameter estimates. 2015, 12(5): 965-981 doi: 10.3934/mbe.2015.12.965 +[Abstract](442) +[PDF](721.6KB) Abstract: This work is the outcome of the partnership between the mathematical group of Department DISBEF and the biochemical group of Department DISB of the University of Urbino "Carlo Bo" in order to better understand some crucial aspects of brain cancer oncogenesis. Throughout our collaboration we discovered that biochemists are mainly attracted to the instantaneous behaviour of the whole cell, while mathematicians are mostly interested in the evolution along time of small and different parts of it. This collaboration has thus been very challenging. Starting from [23,24,25], we introduce a competitive stochastic model for post-transcriptional regulation of PTEN, including interactions with the miRNA and concurrent genes. Our model also covers protein formation and the backward mechanism going from the protein back to the miRNA. The numerical simulations show that the model reproduces the expected dynamics of normal glial cells. Moreover, the introduction of translational and transcriptional delays offers some interesting insights for the PTEN low expression as observed in brain tumor cells. 2015, 12(5): 983-1006 doi: 10.3934/mbe.2015.12.983 +[Abstract](380) +[PDF](653.5KB) Abstract: In this paper we formulate a dynamical model to study the transmission dynamics of schistosomiasis in humans and snails. We also incorporate bovines in the model to study their impact on transmission and controlling the spread of Schistosoma japonicum in humans in China. The dynamics of the model is rigorously analyzed by using the theory of dynamical systems. The theoretical results show that the disease free equilibrium is globally asymptotically stable if $\mathcal R_0<1$, and if $\mathcal R_0>1$ the system has only one positive equilibrium. The local stability of the unique positive equilibrium is investigated and sufficient conditions are also provided for the global stability of the positive equilibrium. The optimal control theory are further applied to the model to study the corresponding optimal control problem. Both analytical and numerical results suggest that: (a) the infected bovines play an important role in the spread of schistosomiasis among humans, and killing the infected bovines will be useful to prevent transmission of schistosomiasis among humans; (b) optimal control strategy performs better than the constant controls in reducing the prevalence of the infected human and the cost for implementing optimal control is much less than that for constant controls; and (c) improving the treatment rate of infected humans, the killing rate of the infected bovines and the fishing rate of snails in the early stage of spread of schistosomiasis are very helpful to contain the prevalence of infected human case as well as minimize the total cost. 2015, 12(5): 1007-1016 doi: 10.3934/mbe.2015.12.1007 +[Abstract](387) +[PDF](993.4KB) Abstract: A mathematical or computational model in evolutionary biology should necessary combine several comparatively fast processes, which actually drive natural selection and evolution, with a very slow process of evolution. As a result, several very different time scales are simultaneously present in the model; this makes its analytical study an extremely difficult task. However, the significant difference of the time scales implies the existence of a possibility of the model order reduction through a process of time separation. In this paper we conduct the procedure of model order reduction for a reasonably simple model of RNA virus evolution reducing the original system of three integro-partial derivative equations to a single equation. Computations confirm that there is a good fit between the results for the original and reduced models. 2015, 12(5): 1017-1035 doi: 10.3934/mbe.2015.12.1017 +[Abstract](452) +[PDF](446.8KB) Abstract: A method for early diagnosis of parametric changes in intracellular protein synthesis models (e.g. the p53 protein - mdm2 inhibitor model) is developed with the use of a nonlinear Kalman Filtering approach (Derivative-free nonlinear Kalman Filter) and of statistical change detection methods. The intracellular protein synthesis dynamic model is described by a set of coupled nonlinear differential equations. It is shown that such a dynamical system satisfies differential flatness properties and this allows to transform it, through a change of variables (diffeomorphism), to the so-called linear canonical form. For the linearized equivalent of the dynamical system, state estimation can be performed using the Kalman Filter recursion. Moreover, by applying an inverse transformation based on the previous diffeomorphism it becomes also possible to obtain estimates of the state variables of the initial nonlinear model. By comparing the output of the Kalman Filter (which is assumed to correspond to the undistorted dynamical model) with measurements obtained from the monitored protein synthesis system, a sequence of differences (residuals) is obtained. The statistical processing of the residuals with the use of $\chi^2$ change detection tests, can provide indication within specific confidence intervals about parametric changes in the considered biological system and consequently indications about the appearance of specific diseases (e.g. malignancies) 2015, 12(5): 1037-1053 doi: 10.3934/mbe.2015.12.1037 +[Abstract](426) +[PDF](2010.9KB) Abstract: The goal of this paper is to analyze a model of cancer-immune system interactions from [16], and to show how the introduction of control in this model can dramatically improve the hypothetical patient response and in effect prevent the cancer from growing. We examine all the equilibrium points of the model and classify them according to their stability properties. We identify an equilibrium point corresponding to a survivable amount of cancer cells which are exactly balanced by the immune response. This situation corresponds to cancer dormancy. By using Lyapunov stability theory we estimate the region of attraction of this equilibrium and propose two control laws which are able to stabilize the system effectively, improving the results of [16]. Ultimately, the analysis presented in this paper reveals that a slower, continuous introduction of antibodies over a short time scale, as opposed to mere inoculation, may lead to more efficient and safer treatments. 2015, 12(5): 1055-1063 doi: 10.3934/mbe.2015.12.1055 +[Abstract](410) +[PDF](343.8KB) Abstract: Based on the reported data until 18 March 2015 and numerical fitting via a simple formula of cumulative case number, we provide real-time estimation on basic reproduction number, inflection point, peak time and final outbreak size of ongoing Ebola outbreak in West Africa. From our simulation, we conclude that the first wave has passed its inflection point and predict that a second epidemic wave may appear in the near future. 2015, 12(5): 1065-1081 doi: 10.3934/mbe.2015.12.1065 +[Abstract](391) +[PDF](447.0KB) Abstract: In this paper, we analyze a general predator-prey model with state feedback impulsive harvesting strategies in which the prey species displays a strong Allee effect. We firstly show the existence of order-$1$ heteroclinic cycle and order-$1$ positive periodic solutions by using the geometric theory of differential equations for the unperturbed system. Based on the theory of rotated vector fields, the order-$1$ positive periodic solutions and heteroclinic bifurcation are studied for the perturbed system. Finally, some numerical simulations are provided to illustrate our main results. All the results indicate that the harvesting rate should be maintained at a reasonable range to keep the sustainable development of ecological systems. 2015, 12(5): 1083-1106 doi: 10.3934/mbe.2015.12.1083 +[Abstract](458) +[PDF](617.3KB) Abstract: A multi-group epidemic model with distributed delay and vaccination age has been formulated and studied. Mathematical analysis shows that the global dynamics of the model is determined by the basic reproduction number $\mathcal{R}_0$: the disease-free equilibrium is globally asymptotically stable if $\mathcal{R}_0\leq1$, and the endemic equilibrium is globally asymptotically stable if $\mathcal{R}_0>1$. Lyapunov functionals are constructed by the non-negative matrix theory and a novel grouping technique to establish the global stability. The stochastic perturbation of the model is studied and it is proved that the endemic equilibrium of the stochastic model is stochastically asymptotically stable in the large under certain conditions. 2015, 12(5): 1107-1126 doi: 10.3934/mbe.2015.12.1107 +[Abstract](351) +[PDF](5989.7KB) Abstract: Mucociliary clearance is the first line of defense in our airway. The purpose of this study is to identify and study key factors in the cilia motion that influence the transport ability of the mucociliary system. Using a rod-propel-fluid model, we examine the effects of cilia density, beating frequency, metachronal wavelength, and the extending height of the beating cilia. We first verify that asymmetry in the cilia motion is key to developing transport in the mucus flow. Next, two types of asymmetries between the effective and recovery strokes of the cilia motion are considered, the cilium beating velocity difference and the cilium height difference. We show that the cilium height difference is more efficient in driving the transport, and the more bend the cilium during the recovery stroke is, the more effective the transport would be. It is found that the transport capacity of the mucociliary system increases with cilia density and cilia beating frequency, but saturates above by a threshold value in both density and frequency. The metachronal wave that results from the phase lag among cilia does not contribute much to the mucus transport, which is consistent with the experimental observation of Sleigh (1989). We also test the effect of mucus viscosity, whose value is found to be inversely proportional to the transport ability. While multiple parts have to interplay and coordinate to allow for most effective mucociliary clearance, our findings from a simple model move us closer to understanding the effects of the cilia motion on the efficiency of this clearance system. 2015, 12(5): 1127-1139 doi: 10.3934/mbe.2015.12.1127 +[Abstract](426) +[PDF](415.0KB) Abstract: The inflammatory response aims to restore homeostasis by means of removing a biological stress, such as an invading bacterial pathogen. In cases of acute systemic inflammation, the possibility of collateral tissue damage arises, which leads to a necessary down-regulation of the response. A reduced ordinary differential equations (ODE) model of acute inflammation was presented and investigated in [10]. That system contains multiple positive and negative feedback loops and is a highly coupled and nonlinear ODE. The implementation of nonlinear model predictive control (NMPC) as a methodology for determining proper therapeutic intervention for in silico patients displaying complex inflammatory states was initially explored in [5]. Since direct measurements of the bacterial population and the magnitude of tissue damage/dysfunction are not readily available or biologically feasible, the need for robust state estimation was evident. In this present work, we present results on the nonlinear reachability of the underlying model, and then focus our attention on improving the predictability of the underlying model by coupling the NMPC with a particle filter. The results, though comparable to the initial exploratory study, show that robust state estimation of this highly nonlinear model can provide an alternative to prior updating strategies used when only partial access to the unmeasurable states of the system are available. 2017 Impact Factor: 1.23	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8034682869911194, "perplexity": 691.6997754043553}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-39/segments/1537267156252.62/warc/CC-MAIN-20180919161420-20180919181420-00340.warc.gz"}
http://www.ck12.org/chemistry/Oxygen-in-Reactions/lesson/Oxygen-in-Reactions/	<meta http-equiv="refresh" content="1; url=/nojavascript/"> # Oxygen in Reactions ## Introduces oxidation from the perspective of oxide compounds. % Progress Progress % Oxygen in Reactions Credit: Image copyright Lucky Business, 2014 Source: http://www.shutterstock.com License: CC BY-NC 3.0 Before (top) and after (bottom) teeth bleaching. [Figure1] Are our teeth sparkling white? Are they attractive? We worry a lot about our smiles. Over the years teeth do discolor some, so the procedure of teeth bleaching has become more and more popular. Best done in a dentist’s office, various chemical preparations containing peroxides are used to whiten the teeth. Less effective, but easier to use are “teeth-whitening” tooth pastes (also containing peroxides) that promise to give you a brighter smile and improve your life in every way. ### Oxygen in Reactions Many elements simply combine with oxygen to form the oxide of that element. The heating of magnesium in air allows it to combine with oxygen from the air to form magnesium oxide (see video below). $2\text{Mg}(s)+\text{O}_2(g) \rightarrow 2\text{MgO}(s)$ Compounds can also react with oxygen, possibly creating oxides of more than one element. When methane burns, carbon dioxide and water are produced. $\text{CH}_4(g)+2\text{O}_2(g) \rightarrow \text{CO}_2(g)+2\text{H}_2\text{O}(g)$ Carbon dioxide is an oxide of carbon, while water is an oxide of hydrogen. Early scientists viewed oxidation as a process in which a substance was reacted with oxygen to produce one or more oxides. In the previous examples, magnesium and methane are being oxidized. Oxidation is also defined as a loss of hydrogen atoms. In the following equation, ethanol is oxidized to acetaldehyde by the loss of two hydrogen atoms: $\text{CH}_3\text{CH}_2\text{OH} \rightarrow \text{CH}_3\text{CHO} + 2\text{H atoms}$ Oxidation does not necessarily require heating. Iron that is exposed to air and water slowly oxidizes in a process commonly known as rusting. Bleaches contain various compounds such as sodium hypochlorite (NaClO), which release oxygen that oxidizes stains. Hydrogen peroxide (H 2 O 2 ) releases oxygen as it spontaneously decomposes. It acts as a bleach and an antiseptic that kills bacteria by oxidizing them. The chemical reaction that is the opposite of oxidation is called reduction. Following from the notion that oxidation was originally thought to mean only the addition of oxygen, reduction was thought to be only the removal of oxygen from a substance. Many naturally occurring metal ores are present as oxides. The pure metals can be extracted by reduction. Iron is obtained from iron(III) oxide by reacting with carbon at high temperatures. $2\text{Fe}_2\text{O}_3(s)+3\text{C}(s) \rightarrow 4\text{Fe}(s)+3\text{CO}_2(g)$ The removal of oxygen from the Fe 2 O 3 means that it is being reduced to Fe. Note that an oxidation process is simultaneously occurring. The carbon reactant is being oxidized to CO 2 . This is an important concept. Oxidation and reduction must happen together. Neither can happen alone in a reaction. Reduction can also be considered as a gain of hydrogen. The reverse of the ethanol → acetaldehyde reaction shown above is a reduction reaction: $\text{CH}_3\text{CHO} + 2\text{H atoms} \rightarrow \text{CH}_3\text{CH}_2\text{OH}$ #### Summary • Oxidation and reduction are defined in terms of reactions with oxygen. • Oxidation and reduction reactions must occur together. #### Practice Answer the questions at the following link: #### Review Questions 1. Give a definition of oxidation in terms of oxygen. 2. Give a definition of reduction in terms of oxygen. 3. Characterize the following reaction in terms of the definitions of oxidation and reduction: $\text{CH}_4(g)+2\text{O}_2(g) \rightarrow \text{CO}_2(g)+2\text{H}_2\text{O}(g)$ ### Image Attributions 1. [1]^ Credit: Image copyright Lucky Business, 2014; Source: http://www.shutterstock.com; License: CC BY-NC 3.0 ### Explore More Sign in to explore more, including practice questions and solutions for Oxygen in Reactions. Please wait... 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https://www.physicsforums.com/threads/poisson-and-binomial-distributions-corrupted-characters-in-a-file.370564/	# Poisson and binomial distributions, corrupted characters in a file 1. Jan 18, 2010 ### Kate2010 A text file contains 1000 characters. When the file is sent by email from one machine to another, each character (independent of other characters) has probability 0.001 of being corrupted. Use a poisson random variable to estimate the probability that the file is transferred with no errors. Compare this to the answer you get when modelling the number of errors as a binomial random variable. Poisson: Let x be the number of corrupted characters. E(X) = 0.001 = a P(X=n) = (0.001^n)(e^-0.001)/(n!) P(X=0) = e^-0.001 Binomial: np = 1000 x 0.001 = 1 When I approximate using poisson but with np instead I get e^-1 which is about 0.37. This doesn't seem right? 2. Jan 18, 2010 ### Staff: Mentor Show us your calculation of P(X = 0) for the binomial case. 3. Jan 18, 2010 ### Kate2010 I used poisson but approximated lambda as np, so ((np)^k)(e^-np)/k! where np = 1000x0.001 = 1 and k = 0, so we get (1^0)(e^-1)/0! = e^-1. I don't know how I could use the proper binomial random variable. 4. Jan 18, 2010 ### Staff: Mentor I believe you are supposed to assume that X is a binomial r.v., where the probability for a given character being in error is .001. You want P(X=0). See this Wikipedia page for more information. 5. Jan 18, 2010 ### Kate2010 Thanks, when I do it that way I get (1000 choose 0)(0.001^0)(1-0.001)^1000 = 0.3676... So, is it when I have calculated my poisson RV that I've gone wrong and I should have done this as I was previously trying to approximate binomial? 6. Jan 18, 2010 ### Kate2010 Actually, have just read up some more on Poisson distributions and I know where I've gone wrong. Thanks for all your help!	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8378203511238098, "perplexity": 1110.1162309939662}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-13/segments/1521257647576.75/warc/CC-MAIN-20180321043531-20180321063531-00186.warc.gz"}
https://lugatgt.org/2001/11/24/latex/	# LaTeX ## 1. Introduction TeX is the document markup language and typesetting engine developed by Don Knuth. LaTeX is a modern set of TeX macro packages that make the parent language much more versatile and easier to use. In essence, LaTeX (latex) takes source code in .tex format, and generates an intermediate .dvi file, which is then processed by dvips to produce printable .ps. In a nutshell, TeX generates output by gluing rectangles of typeset material together. Several letters are glued together to form a word; several of these units are glued together to form paragraphs; paragraph units are glued to figure units and tables units, all of which are just rectangles, and these form the output page. To compile your .tex files on the command line (see the man pages for latex file.texdvips -t letter file -o Or in a Makefile: %.dvi: %.tex latex $& foo - bibtex$*%.ps: %.dvi dvips -t letter -o $@ -C$(NUM) -D$(DPI)$ The intermediate .dvi file is a device independent file which means that it contains all of the typesetting information, but it is not ready to be sent to a rendering device (printer). You may view these intermediate files with xdvi. For actual output by a physical printing device, you will need to convert this using a tool designed to generate the output you want: dvips makes PostScript files, dvipdf makes Proprietary Data Formats, you get the point from the names. (It is also possible to convert from .ps to .pdf, using ps2pdf.) In the following sections, we will cover how to typeset a report and a letter. We’ll cover how to create the finest looking math you have ever seen; how to include tables, figures, and images in your work; and how to cite references. ## 2. Basic LaTeX File All basic LaTeX files have at a bare minimum a declaration of the class of the document to be rendered, which may have options, and begin and end document tags. If you LaTeX a document at this stage, you won’t get any errors, but you won’t get any output. The further addition of LaTeX commands or plain text will be compiled into your output code, as in this example, the (nearly) smallest LaTeX that will compile. You will get a free page number at the bottom. \documentclass{report}\begin{document}Hello, World!\end{document} The class declaration determines what style the rendered document will take, one particular document with no content change at all is rendered significantly differently simply by changing its class from report to article. Options to the different classes include paper size and orientation, font size, and more. They are specified as in \documentclass[12pt,landscape]{book}. Optional arguments in LaTeX are indicated by [ ] pairs, and required arguments by { }. LaTeX source code is basically marked up plain text, so type in your full text, LaTeX it, and then begin adding your special items of which there are many examples in this handout. The first things to modify in your text are to signify a paragraph break with a double character anywhere in a line (the rest of the line is a comment.) To comment a block of code, you must comment every single line. There are certain specific command related characters which must be escaped using a backslash to be represented after processing by LaTeX (examples include: #, %, &, etc. which are coded as \#, \%, \&). Certain useful macros are pre-defined by LaTeX. Macros available in most class files include nicely formatted titles (\title{Title}), author name (\author{Your Name}), and date (\date{\today}}). These are defined before the begin document tag, they are invoked inside the document using \maketitle. You may divide your source code into more manageable pieces by simply chopping it into many .tex files and including them into a master .tex file using \input{subfile.tex}. (These files do not require begin and end document tags, in fact those will break the compilation process; input simply drops the block of text in place of the input macro.) Every logical piece of a document is typically made into a section (\section{Section Title}), we therefore like to put each section into its own LaTeX file, which you can see in the source code for this handout. More than you ever wanted to know about all of the available LaTeX commands can be found in [2] and [3]. There are also LaTeX packages to do things like slides (for Powerpoint-like slides, check out prosper: http://sourceforge.net/projects/prosper/), to format your work for journal submissions, for music typesetting (MuSiXTeX), chemistry, and many other things [1]. ## 3. A Letter to Mom There aren’t too many differences between a letter and a report in LaTeX. To begin with, you define \documentclass{letter} and give yourself begin and end document tags as before. Then you need to define your addressing information (\address{}), name (\name{}), and signature line (\signature{}) (also generally your name) outside of the document tags. Inside the document tags, you can then define multiple letters using \begin{letter}{Mom's address}Hello, Mom!\end{letter} The begin letter tag takes a second argument, the recipient’s address. Then you supply an \opening{Dear John:}, the letter body, and a \closing{Sincerely,}. Enclosures (\encl{}) and carbon copies (\cc{}) can also be added. Then, end your letter. No matter how many letters you put in the document tags, all will get their information about you from the macros at the beginning of the file. Just run latex and dvips as before. This letter also gives two examples of lists, an enumerated list and an itemized list (descriptive lists exist as well.) ## 4. IEEE Math Mathematical equations are a specialty of LaTeX. There isn’t any equation out there that isn’t easily described in the LaTeX language. You can put equations like e=mc2 in the text (using $e=mc^2$). The \$ denotes the start and end of in-line math. Or you can do equations outside the text, and they can be numbered or not. The names of the math macros are generally quite logical as for \lim, \sum, and \alpha. ## 5. Tables Tables are a wonderful way to present certain types of information. In LaTeX we need to first distinguish between two closely related environments with bearing on their construction. The first is the obvious table. This environment wraps around a conceptual table, a block of processed text, but does not itself create any content. tabular is what actually sets blocks of text and line grids together to make a readable table. In the tabular options r, l, c == right, left, center column justifications, and the \| (pipe) creates the vertical lines. \hline makes the horizontal lines, & separates the columns, and \\ ends rows. Go forth and tabulate! Other things that apply globally and occur in this example include the \newcommand{} directive, allowing you to write your own macros, and the \caption{} directive, which is self-explanatory. ## 6. Figures Figures are really quite simple, like the table environment, a figure is simply a wrapper which signifies the block of imagery. Also, like the table environment, it takes a \caption{}. The actual content of a figure can be anything (even a tabular), but it is usually an image. The easiest way to include an image is using the graphicsx package which you must include (using \usepackage{}), which you can then tell that you are using the dvips post-processor. So, we can simply code \includegraphics[width=3in,height=6cm]{figure.eps} and produce a picture (where width and height are optional). ## 7. Citing Sources To include references to works that you have cited in you research, you need a helper of LaTeX called bibTeX. bibTeX bibliography entries are stored in a .bib file. The attached .bib file contains entries for all of the common reference types and many obscure ones. To include a bibliography file in your document, you need to say \bibliography{filename}. To cite the references within your document, you simply use the command \cite{keyword}. Then to actually compile the bibliography into typesettable citation references you run bibTeX as: latex filebibtex filelatex filelatex filedvips -t letter file -o We know this seems like of extra compilation. Because LaTeX can only typeset the text that is available at run-time, the first run of LaTeX will not generate any citations (or table, figure, or section references). Running bibTeX generates two files, .bbl and .blg, which contain the typesetting data we need. We must run LaTeX a second time (and sometimes a third) for the citation numbers to register in the text. If we fail, we will see [?]. ## 9. Resources 1. Michel Goossens, Sebastian Rahtz, and Frank Mittelbach. The LaTeX Graphics Companion: Illustrating Documents with TeX and PostScript . 2. Helmut Kopka and Patrick W. Daly. A Guide to LaTeXe: Document Preparation for Beginners and . Addison-Wesley Publishing Company, Wokingham, England, second edition, 1995. 3. Leslie Lamport. 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http://www.ck12.org/book/CK-12-Middle-School-Math-Concepts-Grade-8/r19/section/3.13/	<img src="https://d5nxst8fruw4z.cloudfront.net/atrk.gif?account=iA1Pi1a8Dy00ym" style="display:none" height="1" width="1" alt="" /> # 3.13: Solve Inequalities Using Addition or Subtraction Difficulty Level: At Grade Created by: CK-12 Estimated7 minsto complete % Progress Practice Inequalities with Addition and Subtraction Progress Estimated7 minsto complete % The students at Floyd Middle School have been working hard fundraising. They sold popcorn, had a bake sale and a car wash. Finally with the time for purchasing band uniforms rapidly approaching, Mrs. Kline gathered the whole band together one afternoon to discuss their profit. “We did very well,” she started. “We raised a total of $12,000 and we had$1,000 in our account, so we have $13,000 to spend on our uniforms. I know that may seem like a lot of money, but uniforms are expensive. We are only going to be able to purchase new jackets for everyone. If we have any money left over, we’ll buy new fingerless gloves because some of the ones we’re using look awful.” “Mrs. Kline, did you already pick the design of the jacket?” Kayla asked from the second row. “Yes. It was one of the ones we voted on last year,” she said holding up a picture of the shiny, new navy jacket. “Now I need a few people to figure out the cost and if we have enough for the gloves too.” Kayla and Juan volunteered to work on the arithmetic. Here is the information Mrs. Kline gave them. The jackets each cost$99.95. The total budget is $13,000. There are 144 students in the band. “We will need to spend$11,512.80 on the jackets,” Kayla said to Juan. “Wow, that’s a lot of money. How much can we spend on the gloves?” That is a great question. It is one that can be answered by writing an inequality. The students need their total to be equal to or less than 13,000. In this Concept, you will learn how to work with inequalities that have addition and/or subtraction in them. Then you will use what you have learned to help Kayla and Juan with the band uniforms. ### Guidance Sometimes, you will have an inequality that is not as straightforward as \begin{align}x>4\end{align}. With this example, we know that the variable will be equal to any number that is greater than four. This is quite easy to work with and we can write a set of numbers to make this inequality a true statement. What if it isn’t that simple? Sometimes, you will see an inequality like this one. \begin{align}x+3>7\end{align} Here we need to figure out the set of numbers that will make this a true statement. We are looking for a number that when added to three is greater than seven. To figure this out, we will need to solve this inequality. Solving an inequality is similar to solving an equation. Here are some number properties that can help you solve inequalities. The addition property of inequality states that if the same number is added to each side of an inequality, the sense of the inequality stays the same. In other words, the inequality symbol does not change. If \begin{align}a>b\end{align}, then \begin{align}a+c>b+c\end{align}. If \begin{align}a \ge b\end{align}, then \begin{align}a+c \ge b+c\end{align}. If \begin{align}a, then \begin{align}a+c. If \begin{align}a \le b\end{align}, then \begin{align}a+c \le b+c\end{align}. What about subtraction? Remember, subtracting a number, \begin{align}c\end{align}, is the same as adding its opposite, \begin{align}-c\end{align}. So, the addition property of inequality applies to subtraction as well. We can also state this as it’s own property. The subtraction property of inequality states that if the same number is subtracted from each side of an inequality, the sense of the inequality stays the same. In other words, the inequality symbol does not change. If \begin{align}a>b\end{align}, then \begin{align}a-c > b-c\end{align}. If \begin{align}a \ge b\end{align}, then \begin{align}a-c \ge b-c\end{align}. If \begin{align}a, then \begin{align}a-c < b-c\end{align}. If \begin{align}a \le b\end{align}, then \begin{align}a-c \le b-c\end{align}. Applying these properties makes our work quite simple. You can think of solving inequalities in the same way that you thought of solving equations. The big difference is that your answer will be a set of numbers and not a single number. Just like with equations, you need to be sure that your answer makes the mathematical statement true. If it doesn’t, then you need to rethink your answer. Now let’s look at solving inequalities. Solve this inequality and graph its solution: \begin{align}n-3<5\end{align}. Solve the inequality as you would solve an equation, by using inverse operations. Since the 3 is subtracted from \begin{align}n\end{align}, add 3 to both sides of the inequality to solve it. Since you are adding the same number to both sides of the inequality, the addition property of inequality applies. According to that property, we know that the inequality symbol should stay the same when we add the same number, 3, to both sides of the inequality. Think back! To solve inequalities, you may need to remember how to add and subtract integers. Pay attention to the sign when you work with these values. \begin{align}n-3 &< 5\\ n-3+3 &< 5+3\\ n+(-3+3) &< 8\\ n+0 &< 8\\ n &< 8\end{align} Now, graph the solution. The inequality \begin{align}n<8\end{align} is read as “\begin{align}n\end{align} is less than 8.” So, the solution set for this inequality includes all numbers that are less than 8, but it does not include 8. Draw a number line from 0 to 10. Add an open circle at 8 to show that 7 is not a solution for this inequality. Then draw an arrow showing all numbers less than 8. Solve this inequality and graph its solution: \begin{align}-2 \le x+4\end{align} Use inverse operations to isolate the variable. Since the 4 is added to \begin{align}x\end{align}, subtract 4 from both sides of the inequality to solve it. Since you are subtracting the same number from both sides of the inequality, the subtraction property of inequality applies. According to that property, the inequality symbol should stay the same when we subtract the same number, 4, from both sides of the inequality. \begin{align}-2 & \le x+4\\ -2-4 & \le x+4-4\\ -2+(-4) &\le x+0\\ -6 & \le x\end{align} Now, we should graph the solution. However, before we can do that, we need to rewrite the inequality so the variable is listed first. The inequality \begin{align}-6 \le x\end{align} is read as “-6 is less than or equal to \begin{align}x\end{align}.” If we list the \begin{align}x\end{align} first, we must reverse the inequality symbol. That means changing the “less than or equal to” symbol \begin{align}(\le)\end{align} to a “less than or equal to symbol” \begin{align}(\ge)\end{align}. So, \begin{align}-6 \le x\end{align} equivalent to \begin{align}x \ge -6\end{align}. This makes sense. If -6 is less than or equal to \begin{align}x\end{align}, then \begin{align}x\end{align} must be greater than or equal to -6. The inequality \begin{align}x \ge -6\end{align} is read as “\begin{align}x\end{align} is greater than or equal to -6.” So, the solutions of this inequality include -6 and all numbers that are greater than -6. Draw a number line from -10 to 0. Add a closed circle at -6 to show that -6 is a solution for this inequality. Then draw an arrow showing all numbers greater than -6. #### Example A \begin{align}x+5<-12\end{align} Solution: \begin{align}x<-17\end{align} #### Example B \begin{align}y-8\le5\end{align} Solution: \begin{align}y\le13\end{align} #### Example C \begin{align}a-5\ge22\end{align} Solution: \begin{align}a\ge27\end{align} Now let's go back to the dilemma at the beginning of the Concept. First, we write an inequality to represent the uniform cost, unknown cost of gloves, and the total budget for everything. The total of the uniforms and gloves must be less than or equal to the total budget. \begin{align}\ 11,512 = \text{cost of uniforms}\end{align} \begin{align}x = \text{budget for gloves}\end{align} \begin{align}\le\end{align}13,000 Here is the inequality. \begin{align}11,512 + x \le 13,000\end{align} We solve the inequality by using inverse operations. \begin{align}x &\le 13,000 - 11,512\\ x & \le \1487.20\end{align} The students will have a maximum budget of $1487.20 to spend on the gloves. ### Vocabulary Equation a mathematical statement using an equals sign where the quantity on one side of the equals is the same as the quantity on the other side. Inequality a mathematical statement where the value on one side of an inequality symbol can be less than, greater than and sometimes also equal to the quantity on the other side. The key is that the quantities are not necessarily equal. Addition Property of Inequality You can add a quantity to both sides of an inequality and it does not change the sense of the inequality. Subtraction Property of Inequality You can subtract a quantity from both sides of an inequality and it does not change the sense of the inequality. ### Guided Practice Here is one for you to try on your own. At the store, Talia bought one item—a$4.99 bottle of shampoo. Let \begin{align}d\end{align} represent the amount in dollars that she handed the clerk. She received more than 5 in change. a. Write an inequality to represent \begin{align}d\end{align}, the number of dollars Talia handed the clerk to pay for the shampoo. b. List three possible values of \begin{align}d\end{align}. Solution Consider part a first. Use a number, an operation sign, a variable, or an inequality symbol to represent each part of the problem. The fact that this problem involves “change” may help you see that you should write a subtraction expression to represent the first part of this problem. To represent how much change Talia received, you will need to subtract the cost of the shampoo from the amount she handed the clerk. The key words “more than”, in this case, indicate that you should use a \begin{align} > \end{align} symbol. Use this information to write an inequality for this problem. \begin{align}& (\text{dollars handed to the clerk}) - (\text{cost of \4.99 bottle of shampoo}) > (\text{\5 in change})\\ & \qquad \qquad \qquad \downarrow \qquad \qquad \qquad \downarrow \qquad \qquad \qquad \qquad \downarrow \qquad \qquad \qquad \quad \downarrow \qquad \quad \downarrow\\ & \qquad \qquad \qquad d \qquad \qquad \qquad - \qquad \qquad \qquad \quad 4.99 \qquad \qquad \qquad > \quad \quad \ \ 5\end{align} So, this problem can be represented by the inequality \begin{align}d-4.99 > 5\end{align}. Next, consider part b. Solve the inequality to help you find three possible values for \begin{align}d\end{align}. To solve this inequality, add 4.99 to both sides. Do not change the inequality symbol. \begin{align}d-4.99 & > 5\\ d - 4.99+4.99 &> 5+4.99\\ d+(-4.99+4.99) &> 5.00+4.99\\ d+0 &> 9.99\\ d &> 9.99\end{align} According to the inequality above, the amount Talia handed the clerk was more than9.99. So, three possible values of \begin{align}d\end{align} are $10.00,$10.99, and $20.00. These are only 3 possible answers. You could choose any amount that is greater than$9.99. ### Practice Directions: Solve the following inequalities. 1. \begin{align}x+4>10\end{align} 2. \begin{align}y-11<20\end{align} 3. \begin{align}a+2<1\end{align} 4. \begin{align}b+3 \ge 5\end{align} 5. \begin{align}y-2 \le -4\end{align} 6. \begin{align}x+1 \ge -5\end{align} 7. \begin{align}x-3<11\end{align} 8. \begin{align}x-4>-3\end{align} 9. \begin{align}y+7>22\end{align} 10. \begin{align}a-6\ge-1\end{align} 11. \begin{align}b+14>20\end{align} 12. \begin{align}x-24>-11\end{align} 13. \begin{align}a+3\le-9\end{align} 14. \begin{align}x-12>1\end{align} 15. \begin{align}y+13>-33\end{align*} ### Notes/Highlights Having trouble? Report an issue. Color Highlighted Text Notes ### Vocabulary Language: English You can add a quantity to both sides of an inequality and it does not change the sense of the inequality. If $x > 3$, then $x+2 > 3+2$. Equation An equation is a mathematical sentence that describes two equal quantities. Equations contain equals signs. inequality An inequality is a mathematical statement that relates expressions that are not necessarily equal by using an inequality symbol. The inequality symbols are $<$, $>$, $\le$, $\ge$ and $\ne$. Subtraction Property of Inequality The subtraction property of inequality states that the subtraction of equal amounts from both sides of an inequality will not change the sense of the inequality. 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http://quant.stackexchange.com/tags/option-pricing/hot?filter=year	# Tag Info Q: What does the risk-neutral price represent if the option is not replicable? In an incomplete market, there is no unique martingale measure but instead a set $Q$ of equivalent martingale measures. Consequently, there is an interval of arbitrage-free prices: $\Big( inf_{\mathbf{Q} \in Q} E_{\mathbf{Q}}[DX], sup_{\mathbf{Q} \in Q} E_{\mathbf{Q}}[DX] ... 5 The following paper gives you really all of the missing steps in a very detailed form: Black-Scholes Option Pricing Formula by Michael Tomas and Ravi Shukla From the paper: "This presentation is purely for pedagogical purposes. In the course of doing work on option pricing, we found no complete solution for the Black-Scholes model. By complete, we mean ... 4 The dynamics of the underlying stock process are obviously crucial to the derivative's price. Thus if you don't necessarily assume$S_t$to be log normally distributed (B&S-Model) you won't get the same price even if the market is arbitrage free. Example: Assume$S_t=C \forall t \in \mathbb{R}^+$and$r=0$. Thus$S_t$is constant and the interest ... 4 Most of the time, when you have a simple SDE without a drift, it's a martingale because the Wiener process itself is a martingale. In your example, you have a constant with the Wiener process, therefore the whole process must also be a martingale because the expectation is clearly X(t). However, we can't conclude a driftless SDE is always a martingale. ... 4 I would use the following arguments: If the option were on the first throw of the dice, then we would price it using the expectation, which is$3.5$(=$(1+2+\cdots+6)/6$. Now we have a 2 stage game: First throw : if the player throws more than$3.5$points, i.e.$4,5,6$, then there is no sense in throwing again. If he throws$1-3$then it makes sense to ... 4 The condition $$ud=1\text{, or equivalently }u=1/d$$ is necessary to ensure convergence of the Binomial tree's mean$\mu$and standard deviation$\sigma$to nonfinite values when$n$(number of steps) goes to infinity. Cox-Rubinstein-Ross showed in their famous paper, that to achieve this, we must have: $$u=e^{\sigma\sqrt{t/n}}\text{, ... 4 Very simply, Ross' framework assumes a great deal to extract the true pricing kernel. Time homogeneity, additively separable state dependent utility, (discrete time Markovian structure - though these have been relaxed.) In particular, there are two schools of criticism, one is that time homogeneity makes little sense in the real market. In fact, the Recovery ... 4 In three bullet points: Efficiency: the obtained prices maximize assumed utilities of different agents. In their paper "The Valuation of Option Contracts and a Test of Market Efficiency", Cohen, Black and Scholes compare the theoretical value of options to their market price. The efficiency is in this sense: can agents obtain more or less in practice than ... 4 it doesn;t imply \ln S_T=\ln S_0+rT+σW^Q_T it implies \ln S_T=\ln S_0+(r-0.5\sigma^2)T+σW^Q_T look up Ito's lemma. This is covered in just about any book on financial maths including my own Concepts etc 4 Your characterisation is correct but incomplete. 1) The most important part of Black-Scholes is not the model but the more general framework of dynamic hedging: you can replicate your payoff by continuously trading the underlying and the amount (delta) you should hold is the derivative of the current premium with respect to the current spot. This is a much ... 3 The Black-Scholes price of this option is approximately 14.8. When I run a Monte Carlo simulation with 10000 paths and "exact" time stepping, I get results very close to this value. You are simulating the terminal asset price with the first-order Euler approximation over multiple time steps:$$S(t+\Delta t)= S(t) + rS(t)\Delta t + \sigma ... 3 Benoit Mandelbrot applied fractals and self-similarity to financial markets and the hurst exponent has its roots in chaos theory. Look at this article from Wilmott magazine. Just a personal note: I have not worked that much with this kind of theory so far but I also have not seen any of my peers being exceptionally sucessfull with these methods. 3 Asian options: strike is average of underlying over tenor. Underlying is stochastic. Options with kock-ins/knock-outs: Underlying is stochastic and may cross the kock threshold as it evolves. Option value depends on this cross or lack thereof (boolean). Options on Options, too. Motivations for Asian options you can google. Kock-ins and knock-outs ... 3 The error is, you are not storing the random numbers for the same path at the end: xbefore = x + ctau + sigmasqrt(tau)randn() A = muA + sigmaArandn(); xafter = xbefore + A; But then at end you set a different path here by creating a new random number: xT = log(S0)+(c+muAlambda)T+sqrt((sigma^2+(muA^2+sigmaA^2)lambda)T)*randn(); randn() ... 3 These options can be priced by adding an early exercise premium value to the intrinsic value: http://www.statistics.nus.edu.sg/~stalimtw/PDF/lb-float.pdf 3 you don't need$ud=1.$In fact, there are now about 30 binomial trees which converge to Black--Scholes in the large step limit. Most of them do not have$ud=1.$All you need is $$d < e^{r \Delta t} < u$$ The tree recombines provided$u$and$d$don't change from step to step. See my book More Mathematical Finance for a comprehensive review and ... 3 There are lots of papers online and here are a few I would suggest math.umn riskworx G. Dimitroff, J. de Kock Nowak, Sibetz I you have matlab there is an step step example to calibrate SABR model. Since it uses the financial toolbox of matlab for a few functions I dont think you can replicate it in any other language. There must be C++ code available ... 3 You can view the price of an option as the cost to dynamically replicate it. The more volatility, the more costs you will have trading the underlying to keep your delta equal to 0 (I'm assuming you sold the option, hence a negative gamma position). So, if at any spot, any date your local vol is above 0.194, rebalancing the portfolio will be constantly more ... 3 Think of moving volatility in the other direction. As volatility approaches zero, any call strike strictly smaller than the ATM strike,$K<K_{ATM}$, will have zero probability of ending in the money, and the corresponding option value will be zero. An infinitesimally small change in stock price will not move$K$past$K_{ATM}$, so the option value ... 3 I found and answer to my own question. So, I post it here for people who maybe have the same problem. The answer, however, is quite intuitive. The last observation used for the estimation of the physical density is also the time point where the investors know the most about the physical density because at this point the most possible historical observations ... 3 Simply put, no. Vega depends on a variety of factors (including the level/price of the underlying asset). However, vomma/volga/vega convexity (whatever you want to call dVega/dIV) is always positive. So as IV increases, the vega of an option increases - I think this might have been what you were getting at. It's important to understand that IV is an input ... 2 LSM is very fiddly. The most important things in my view are 1) don't believe anyone who says that the choice of basis functions doesn't matter. 2) implement an upper bounder, eg Andersen--Broadie (2003) or Joshi-Tang (2014) so you can tell if your prices are good 3) do two passes, one to build the strategy, one to price, if they give very different ... 2 American options pricing (swaption is just a kind of option) is a bit tricky due to the early exercise. Here is a page listing possible approaches, including some numeric methods, and some close form approximation formula. As I understand, lattice methods (tree, PDE discretization such as forward shooting) are fine to price American options. There're ... 2 As I see it the question does not enforce that the market is free of arbitrage. This is why you can get to contradicting prices. Thus you can't actually apply a risk-neutral argument here without making additional assumptions. You yourself provide the example of such an arbitrage. If the underlying process had a B&S dynamics you could just borrow money ... 2 Assume the price follows a lognormal process. We can convert it into a problem of finding the probability of a standard Brownian motion particle starting from$0$and hitting$x$before time$t$, or its first passage time$\tau_x$being less than$t$. This can be derived through the reflection principle. The paths crossing$x$are exactly paired up by the ... 2 There is a whole family of GARCH option pricing models; ones with complex distributions, leverage effects, skewness parameters etc. For an example see Christoffersen and Jacobs (2004). Some example GARCH models: NGARCH EGARCH TGARCH Some distributions that can be used: Hyperbolic Normal Inverse Gaussian Variance Gamma and the generalized form ... 2 Generally speaking, if you have two or three sources of noise, you are still going to be much better off pricing American options on a lattice than via LSMC. Too often, LSMC becomes the refuge of academics lacking patience to learn proper lattice techniques. Now, you can frequently reduce the difficulty of pricing American options by considering the ... 2 The problem with your formula is the equation sign$=$. The second order finite difference is only an approximation to the true gamma: $$f^{\prime \prime}(x) \approx \frac{f(x+h)-2f(x)+f(x-h)}{h^2}.$$$h$can not be a result. Ideally, it should be small (whatever that means), so your original choice of$1\text{bp}$seems appropriate for this ... 2 Historical returns are not to be used 'untreated' for the calculation of option prices. The expectation that you will be using in Monte Carlo will take the form $$C(K,T) = E^Q\{D(T)\ \max[0, S_T-K, 0]\}$$ where$T$is the maturity,$K$is the strike price,$S$is the stock price and$D\$ is the discount factor. But the expectation is taken under the 'risk ...	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8352516293525696, "perplexity": 1022.0228491058127}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-14/segments/1427131297195.79/warc/CC-MAIN-20150323172137-00124-ip-10-168-14-71.ec2.internal.warc.gz"}
http://mathoverflow.net/questions/125281/coutour-integral-of-gamma-functions	# Coutour Integral of Gamma Functions How do I solve the Integral $$\frac{1}{2\pi j} \oint \frac{b^{ - s} \Gamma[2 + i - s] \Gamma[s] \Gamma[-1 - i + s]}{ (2 + i - s) \Gamma[3 + i - s]} \:\mathrm{d}s$$ This integral is an inverse Mellin transform. Therefore, the contour extends from $l+j\infty$ to $l-j\infty$, where $l\in\mathbb{R}$. $j=\sqrt{-1}$ $b \in\mathbb{R},\quad b>0$ $i\in\mathbb{R}, \quad i\ge 0$ $\Gamma(.)$ is the gamma function. Does it make any difference when $i$ becomes an integer? - you mean without telling us how a depends on s? – Carlo Beenakker Mar 22 '13 at 15:08 sorry...just fixed it – Remy Mar 22 '13 at 15:11 What does $ii$ mean? And is $j^2=-1$? – Daniel Loughran Mar 22 '13 at 17:00 sorry ..fixed it again ... it is hard to type using a tablet ... ii is an integer, I updated the equation – Remy Mar 22 '13 at 19:11 Why not use $\Gamma[3+i-s]=(2+i-s)\Gamma[2+i-s]$ to cancel a Gamma function in the numerator and denominator? – Stopple Mar 22 '13 at 22:45 show 1 more comment	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9647831916809082, "perplexity": 1466.7005396447173}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-15/segments/1397609535745.0/warc/CC-MAIN-20140416005215-00123-ip-10-147-4-33.ec2.internal.warc.gz"}
https://www.mail-archive.com/search?l=vim%40vim.org&q=from:%22Charles+E+Campbell+Jr%22&o=newest&f=1	### Re: ex editor C.Moncrieff wrote: I guess that this email group may not be the group I need. I'm afraid you're stuck, at least as far as official vim groups go. There's this one and vim-development, primarily. See http://vim.sourceforge.net/community.php for the complete list. What I consider to be highly undesirable new features make ex (and perhaps vi/vim) extremely awkward to use on MACs and I would dearly like to be able to replace ex by a more comfortable older version eg not wiping image of recent changes on screen on exit. set nors If that doesn't do the trick, try set t_ti= t_te= (but this will only help with console vim, not gvim) undo to undo just the last change by default - not all changes since start of session. See :help 'undolevels' etc Any suggestions what to do or where to go for help Seems to me that this mailing list is best for what you're inquiring about. Regards, Chip Campbell ### Re: vim not opening directories Reid Thompson wrote: I have a .vimrc. it has Use Vim settings, rather then Vi settings (much better!). This must be first, because it changes other options as a side effect. set nocompatible [EMAIL PROTECTED]:~$/usr/bin/vim src [EMAIL PROTECTED]:~$ /usr/bin/gvim src * make sure that your account has read-write access (if somehow its owned by root...) * In addition to set nocompatible, you should also have: (in your .vimrc) if version = 600 filetype plugin indent on endif * Check that you in fact have a .vimrc, not a .gvimrc, for this. If you well, it loads after the plugins would, and so the filetype plugin on won't be effecacious. * Fire up vim; check on $VIMRUNTIME -- make sure that plugin/netrw.vim and autoload/netrw.vim are both there and readable by you as a user. Regards, Chip Campbell ### [Fwd: Re: gvim 7 highlight search string] I believe this was meant for the vim mailing list... ---BeginMessage--- Thanks all for the replies. I have a relatively fresh install of Debian Testing. I don't believe I have manually modified any system-level configuration files. All my settings are in ~/.gvimrc and ~/.vimrc Actually this is happening on two systems. My debian testing system at home and my work machine which is running RHEL 4. I believe I compiled vim/gvim from source at work, although here at home I'm using the debian packaged one. On 6/1/07, Charles E Campbell Jr [EMAIL PROTECTED] wrote: Brian E. Lozier wrote: In the old gvim, doing a search (/something) highlights all something in red. In gvim 7, it doesn't highlight all occurrences. Is there a way to turn this back on? I suspect that you may be having problems because you made changes to files in files in your former$VIMRUNTIME (use :echo $VIMRUNTIME when running vim to see where that is). Those files should not be changed, added to, etc, unless you don't mind having to re-do all such changes when next you upgrade vim. Instead: * put settings, most customizations, etc in$HOME/.vimrc (linux) $HOME\_vimrc (windows) You can find out where your$HOME is by typing :echo $HOME when you're running vim. * Put plugins into$HOME/.vim/plugin/ (linux) $HOME\vimfiles\plugin\ (windows) * Put autoload plugins into$HOME/.vim/autoload/ (linux) $HOME\vimfiles\autoload\ (windows) * Put colorschemes into$HOME/.vim/colors/ (linux) $HOME\vimfiles\colors\ (windows) The setting in question here is: hls You'll probably should include the following in your .vimrc (_vimrc), too: set nocp if version = 600 filetype plugin indent on endif Regards, Chip Campbell ---End Message--- ### Re: gvim 7 highlight search string Brian E. Lozier wrote: Thanks all for the replies. I have a relatively fresh install of Debian Testing. I don't believe I have manually modified any system-level configuration files. All my settings are in ~/.gvimrc and ~/.vimrc Actually this is happening on two systems. My debian testing system at home and my work machine which is running RHEL 4. I believe I compiled vim/gvim from source at work, although here at home I'm using the debian packaged one. Charles Campbell wrote: The setting in question here is: hls You'll probably should include the following in your .vimrc (_vimrc), too: set nocp if version = 600 filetype plugin indent on endif * do you have a$HOME/.vimrc file? (wasn't clear from your response; I wasn't referring to any manual modifications done to the new system level configuration files, but was wondering if your previous vim work depended on such manual modifications to the previous system level configuration files) * do you have (at least) the four lines mentioned above in your .vimrc file? (you'll probably want syntax on , too) * do you have set hls in your .vimrc file? * if you do have such a file, is it owned/readable by you? (some folks were having problems with $HOME/.viminfo files owned by root) * what does vim --version show? (I'm wondering here if its one of the minimal vim compiles) Regards, Chip Campbell ### Re: Problems with netrw directory listing Gary Johnson wrote: On 2007-06-03, Seth Mason [EMAIL PROTECTED] wrote: It seems like the spaces in the directory name is causing problems. If I open a file in the directory and then use ':cd %:h' everything works fine so it seems like the problem is not with vim(?). Any help or direction to go from here would be greatly appreciated. I see the problem. I believe it is a bug in autoload/netrw.vim (at line 1593 in version 109) in the definition of the c command: nnoremap buffer silent c :exe cd .b:netrw_curdircr Any spaces in b:netrw_curdir are not escaped and the directory name is not in quotes, so the cd command sees any spaces as separators. Please try netrw v110g available from my website: http://mysite.verizon.net/astronaut/vim/index.html#NETRW I've tested the fix under Linux; please try it out under XP. Regards, Chip Campbell ### Re: collapsing single lines of html tag attributes via plugin?? Howard Glynn wrote: snip I wondered whether there was a plugin somewhere that was able to abbreviate or partially hide the detail so i can see the overall structure more clearly. In essence I would like to collapse huge (single) lines of tags to something like a id=xyz href=/img ... - where implies I could expand if required. I'm sure it is probably possible to craft a plugin to do this, i just have some urgent deadlines right now ;) snip Hello! Sounds like Vince Negri's conceal patch to vim would come in handy for this. Vim's current folding is on a line-by-line basis; Negri's patch can also perform concealing in lines. You can get his patch at: http://vince.negri.googlepages.com/ Here's an example, although it may conceal more than what you've requested... if has(conceal) if conc == 0 let conc= 3 endif syn clear syn region htmlTag conceal start= end= endif So this will conceal anything between ... . One neat thing; even though I've selected conceal level 3, nonetheless, when your cursor is atop a line that line will not be concealed. So editing may proceed, as that's what Vim's for. A more comprehensive (but not html-related) example of concealing is available at my website: see AnsiEsc.vim. This plugin will conceal ansi escape codes and perform proper colorizing of the text based on the concealed ansi codes. Vince N has a tex.vim syntax using concealment, too, somewhere... BTW, folks -- if more people than H Glynn would want this -- let Bram know! He's under the impression that its not wanted very much, which is why I presume its not in vim 7.x. Vince's patch also supports ownsyntax. Read about it at his website. Regards, Chip Campbell ### Re: gvim 7 highlight search string Brian E. Lozier wrote: In the old gvim, doing a search (/something) highlights all something in red. In gvim 7, it doesn't highlight all occurrences. Is there a way to turn this back on? I suspect that you may be having problems because you made changes to files in files in your former$VIMRUNTIME (use :echo $VIMRUNTIME when running vim to see where that is). Those files should not be changed, added to, etc, unless you don't mind having to re-do all such changes when next you upgrade vim. Instead: * put settings, most customizations, etc in$HOME/.vimrc (linux) $HOME\_vimrc (windows) You can find out where your$HOME is by typing :echo $HOME when you're running vim. * Put plugins into$HOME/.vim/plugin/ (linux) $HOME\vimfiles\plugin\ (windows) * Put autoload plugins into$HOME/.vim/autoload/ (linux) $HOME\vimfiles\autoload\ (windows) * Put colorschemes into$HOME/.vim/colors/ (linux) $HOME\vimfiles\colors\ (windows) The setting in question here is: hls You'll probably should include the following in your .vimrc (_vimrc), too: set nocp if version = 600 filetype plugin indent on endif Regards, Chip Campbell ### Re: GSoC Regexp engine Ian Young wrote: I have a couple questions to start things off. First: I couldn't see much need for 'fuzzy matching' in Vim, but some of you are probably much better acquainted with regexp use cases than I am. Would this be a useful feature to have available? As you likely know, fuzzy matching hasn't been available in Vim. One place it has been useful is in suggesting spelling corrections; I myself used agrep in the engspchk.vim plugin to support fuzzy matching. Bram already has a spelling error suggestion feature, so I have no idea if the fuzzy regex would help with it or not. What I think could be more useful would be boolean logic for regexp. My LogiPat plugin provides this capability, but undoubtedly it'd be better if somehow it could be incorporated. The resulting patterns from LogiPat seem to me to be somewhat opaque. Regards, Chip Campbell ### Re: flist tree question onesupermanone wrote: I am a newbie at using gvim. I am using gvim ver 6.4 on linux. I wanted to set up the flist tree on my machine. Dr Chip initially wrote this script. The explaination is at the following site mysite.verizon.net/astronaut/vim/index.html under title C/C++ Functions: prototypes, hints, etc. I have downloaded the flist.tar.gz file. When I untar it I see a lot of C code which I compiled and got an executable flist. Now at this point I have no idea how to incorporate it in my gvim. What do I need to do to set this up. Dr Chip was talking about a FlistTree.vim but I can't seem to find it anywhere. This seems like a cool concept that we can get a function tree. You'll find it at: http://mysite.verizon.net/astronaut/vim/index.html#FLISTTREE Enjoy! Chip Campbell ### Re: A performance question (patch included) John Beckett wrote: A.J.Mechelynck wrote: What about a different function to return, say, the number of 1K blocks (or the number of times 2^n bytes, with a parameter passed to the function) that a file uses? Yes, that's a much more general and better idea. Since there's probably not much need for this, I think that simplicity would be good. That is, have the function work in a fixed way with no options. Re Dr.Chip's LargeFile script: It occurs to me that another workaround would be to use system() to capture the output of 'ls -l file' or 'dir file' (need an option for which). Then do some funky editing to calculate the number of digits in the file length. If more than 9, treat file as large. I'm playing with a tiny utility to help the LargeFile script. Bluesky: Its code (64-bit file size) could potentially be incorporated in Vim. I'll post results in vim-dev. (I've moved this over to vim-dev) I've attached a patch to vim 7.1 which extends getfsize(); with the patch, getfsize() takes an optional second parameter which gives one the ability to specify a unitsize. In other words, getfsize(eval.c) - 478347 (after the patch) getfsize(eval.c,1000) - 479 (truncated upwards) I'll be awaiting Bram's input before making use of this in LargeFile.vim ! Regards, Chip Campbell * src/o_eval.c2007-05-25 08:52:12.0 -0400 --- src/eval.c 2007-05-25 09:04:43.0 -0400 * * 7094,7100 {getcwd,0, 0, f_getcwd}, {getfontname, 0, 1, f_getfontname}, {getfperm, 1, 1, f_getfperm}, ! {getfsize, 1, 1, f_getfsize}, {getftime, 1, 1, f_getftime}, {getftype, 1, 1, f_getftype}, {getline, 1, 2, f_getline}, --- 7094,7100 {getcwd,0, 0, f_getcwd}, {getfontname, 0, 1, f_getfontname}, {getfperm, 1, 1, f_getfperm}, ! {getfsize, 1, 2, f_getfsize}, {getftime, 1, 1, f_getftime}, {getftype, 1, 1, f_getftype}, {getline, 1, 2, f_getline}, * *** 10135,10142 { if (mch_isdir(fname)) rettv-vval.v_number = 0; ! else rettv-vval.v_number = (varnumber_T)st.st_size; } else rettv-vval.v_number = -1; --- 10135,10151 { if (mch_isdir(fname)) rettv-vval.v_number = 0; ! else if (argvars[1].v_type == VAR_UNKNOWN) rettv-vval.v_number = (varnumber_T)st.st_size; + else + { + unsigned long unitsize; + unsigned long stsize; + unitsize= get_tv_number(argvars[1]); + stsize= st.st_size/unitsize; + if(stsizeunitsize st.st_size) ++stsize; + rettv-vval.v_number = (varnumber_T) stsize; + } } else rettv-vval.v_number = -1; runtime/doc/o_eval.txt 2007-05-25 09:00:08.0 -0400 --- runtime/doc/eval.txt2007-05-25 09:06:19.0 -0400 * * 1615,1621 getcmdtype() String return the current command-line type getcwd() String the current working directory getfperm( {fname})String file permissions of file {fname} ! getfsize( {fname})Number size in bytes of file {fname} getfontname( [{name}])String name of font being used getftime( {fname})Number last modification time of file getftype( {fname})String description of type of file {fname} --- 1615,1621 getcmdtype() String return the current command-line type getcwd() String the current working directory getfperm( {fname})String file permissions of file {fname} ! getfsize( {fname} [,unitsize])Number size in bytes of file {fname} getfontname( [{name}])String name of font being used getftime( {fname})Number last modification time of file getftype( {fname})String description of type of file {fname} * *** 2819,2827 getcwd() The result is a String, which is the name of the current working directory. ! getfsize({fname}) getfsize() The result is a Number, which is the size in bytes of the given file {fname}. If {fname} is a directory, 0 is returned. If the file {fname} can't be found, -1 is returned. --- 2819,2829 getcwd() The result is a String, which is the name of the current working directory. ! getfsize({fname} [,unitsize]) getfsize() The result is a Number, which is the size in bytes of the given file {fname}. + If unitsize is given, then the file {fname}'s size will be + returned in units of size unitsize ### Re: A performance question (patch included) A.J.Mechelynck wrote: I'm not sure what varnumber_T means: will st.stsize (the dividend) be wide enough to avoid losing bits on the left? varnumber_T is int (long if an sizeof(int) = 3). st.stsize 's size depends on whether 32bit or 64bit integers are available. So, its possible to lose bits: pick a small enough unitsize and a large enough file, st.stsize will end up not being able to fit into a varnumber_T. After all, unitsize could be 1, and getfsize() will behave no differently than it does now. However, unitsize could be 100. My patch divides st.stsize by the unitsize first; presumably in whatever arithmetic is appropriate for working with st.stsize. Regards, Chip Campbell ### Re: A performance question (patch included) A.J.Mechelynck wrote: Yes, yes, but before the division, will it be able to hold the file size? (sorry, I meant st.st_size) Will mch_stat (at line 10134, one line before the context of your patch) be able to return huge file sizes? mch_stat is variously defined, depending on o/s. Under unix, that's the fstat function. This function returns a pointer to a struct stat; the member in question is: st_size. (off_t st_size;/* total size, in bytes /) So, st_size is an off_t. Under linux, an off_t is typedef __kernel_off_toff_t So, I suspect that st_size will be sized by the o/s to handle whatever size files it can handle. Someone with a 64-bit machine, perhaps, could examine this further? BTW, I'm also under the impression that ls itself uses fstat(), so its not likely to be any more informative. Regards, Chip Campbell ### Re: Netrw edit file Eric Smith wrote: When I am in vim, I can edit a file after selecting form the explorer, however I can only :read a file if I use Nread I'm not sure what you mean by this -- :r file works normally. If the file is an url style: :r ftp://somehost/path/to/file then netrw will read the file, too. How do I :edit from within vim? Place cursor on the target file; press the cr. Regards, Chip Campbell ### Re: A performance question Robert M Robinson wrote: That brings me to my question. I have noticed that when editing large files (millions of lines), deleting a large number of lines (say, hundreds of thousands to millions) takes an unbelieveably long time in VIM--at least on my systems. This struck me as so odd, I looked you up (for the first time in all my years of use) so I could ask why! The LargeFile.vim plugin helps to speed up the editing of large files: http://vim.sourceforge.net/scripts/script.php?script_id=1506 It does so by changing a number of things: no syntax highlighting, no undo, etc. Regards, Chip Campbell ### Re: A performance question John Beckett wrote: Peter Palm wrote: http://www.vim.org/scripts/script.php?script_id=1506. Indeed, among other things, this disables the swap file for 'large' files, which should really speed up things. I was going to report the following issue to vim-dev after I got a chance to investigate it a little further, but it seems appropriate to mention it now. I did some work with a 3GB text file on Win32, using Vim 7.0 and Dr.Chip's LargeFile.vim script from Tip 1506 above. The result was really ugly. The script failed to notice that 3GB was large because the Vim function getfsize(f) returned a negative number. Sounds like the filesize is getting stored in a 32bit signed number, and overflowing. Is the negative number -1 (that would mean file can't be found)? If not, then perhaps that fact could be used to extend the LargeFile's ability to catch large files: trigger when getfsize() returns a number -1. Please let me know what getfsize() is actually returning when applied to that 3GB file. Regards, Chip Campbell ### Re: can i map the number pad enter or somesuch? shawn bright wrote: hello all, Is the enter key on the numeric keypad different than the enter key of the keyboard? i was thinking that it would be super handy to map it to gg. I have a lot of long files to mess around with. I believe the NumLock key modifies the behavior of the number pad keys. To see if your vim will respond to something from it, use insert mode and ctrl-v: i ctrl-v enter ctrl-v numberpad-enter If they're different, you should be able to use it in a mapping. Regards, Chip Campbell ### Re: Vim71: undocumented change for netrw plugin. [EMAIL PROTECTED] wrote: My point is : The following should be added to line 81 of pi_netrw.txt version 2007 May 08. :let loaded_netrwPlugin = 1 If DrChip thinks the document should not change, then the netrwPlugin might have to be changed to still recognize the loaded_netrw variable. That's an awful lot of text just to mention that there's an omission from the help! Anyway, I have no problem putting the extra documentation note in. It'll be part of the runtime archives, assuming that Bram approves, when I next give him an updated netrw. This variable's presence allows folks to get updated netrw.vim versions, placed in their personal .vim/ (vimfiles\) to take precedence over the system versions; ie. updating no longer requires removal of the system versions. Regards, Chip Campbell ### Re: b (move cursor one word back) has annoying delay Harlan Harris wrote: Hi, I'm using a freshly compiled version of Vim 7.1 on a RedHat Enterprise Linux 4 (U5) machine. In both this version of Vim, and in the factory-installed version (6.3), there is a weird behavior where the b key, which sends the cursor back a word, has an annoying delay. The w key does not have this delay. When I press w, the cursor moves to the right immediately. When I press b, however, although vi thinks the cursor has moved (biasdf puts asdf at the beginning of the previous word), the visual cursor does not immediately move. The cursor's position is only updated at the beginning of the next normal flash cycle, which is a second or two later. Until this, the visual cursor stays at the old position. Needless to say, this is really weird and annoying. And to make it even more weird, this is a problem both with the text version of vim, run under an xterm, and under gvim. I believe that this was not always a problem, and that some recently-updated RHEL library change may have caused it. (Not the U4 to U5 change, though, as the problem preceded that upgrade.) Anyway, has anyone else seen this behavior? Is there a workaround? Or a patch? The press-b-get-a-cup-of-joe thing is getting old... Sounds like you have a map beginning with the letter b; so, what happens when: :map b Do you have any such mappings? If so, vim is waiting a bit to see if the rest of the map is going to be typed. Regards, Chip Campbell ### Re: Problems with netrw scp David Rennalls wrote: Hi, I'm having some trouble getting netrw v109(vim 7.1 win WinXP) working with scp. :Nread scp://[EMAIL PROTECTED]:/etc/hosts ..results in the following errors. warning* (netrw) unable to comply with your requestscp://[EMAIL PROTECTED]:/etc/hosts Enclosing the URL with double quotes makes no difference either. :messages NetrwMessage --No lines in buffer-- Error detected while processing function netrw#NetRead: line 91: E121: Undefined variable: b:netrw_fname E116: Invalid arguments for function s:GetTempfile(b:netrw_fname) apply correct suffix E15: Invalid expression: s:GetTempfile(b:netrw_fname) apply correct suffix line 360: E108: No such variable: b:netrw_fname I get the same error no matter what g:netrw_scp_cmd is set to. There's no command window popping up when the Nread is done so I don't think it's even attempting to run the scp executable (which is pscp in my case). Here's some pointers: * Did you know that you don't need to use :Nread? Just :r ... would be fine. * Drop the second colon from scp://[EMAIL PROTECTED]:/etc/hosts AND I suspect you want /etc/hosts, not /root/etc/hosts (/root generally acts as the home directory for root), so try using: scp://[EMAIL PROTECTED]//etc/hosts * Did you read :help netrw-pscp, :help netrw-p8 for how to set netrw up to use pscp? Regards, Chip Campbell ### Re: calling normal commands from ex/a function fREW wrote: Hey everyone, How do I have a function call Normal commands? Example: I'd like to make a function that will open a certain file, and then set the foldlevel to 1, and then go to the right window. So I have: function TodoListMode() execute :e ~/.todo.otl execute :Calendar endfunction and then after the second command I want to do: ctrlwl zM zr * may I point out that you're using execute when you don't need to. * you're already in ex mode; no need to use colons to do ex mode commands * ctrl-w_l can be performed with wincmd l . * to perform normal mode commands in a function, use norm! (the exclamation prevents any maps from interfering) So, with these points in mind: fun! TodoListMode() e ~/.todo.otl wincmd l norm! zMzr Calendar endfun Now, I confess that I didn't test this... Regards, Chip Campbell ### Re: Vim 7 show current column Gary Johnson wrote: On 2007-05-10, Brian E. Lozier [EMAIL PROTECTED] wrote: In vim 6, a line at the bottom would show the column the cursor is over, so I could see like, colymn 79 or whatever. On vim 7 (gvim, more specifically), the status line at the bottom doesn't show up. Is there a way to enable it? If you want the full status line, set laststatus=2 If you just want to see the cursor position, set ruler I don't know why it was there for you in vim 6 but not in vim 7 unless your upgrade process did more than just change the vim binaries and runtime files. Perhaps your new installation changed the system vimrc as well. Or, perhaps you did your customization in a system file such as /usr/local/vim/vim60/vimrc.example? In that case, you can expect it to be wiped out during updates. Instead, do your customization work in your .vimrc in your home directoryand these little gotchas will stop happening. If you don't know where your home directory is... vim :echo$HOME (if that doesn't show anything...) :echo $VIM :q should suffice to let you know your home is, at least from vim's viewpoint. BTW, if that's in fact what you did -- I expect vim60/vimrc.example to still be there; it's just not in vim70/ . Regards, Chip Campbell ### Re: what feature is required to return to last editing position? [EMAIL PROTECTED] wrote: When opening a file in vim, the cursor will move to the last position when the file was saved. The feature is enabled by some autocommands in vimrc_example.vim, I copied the code into my .vimrc and use it in all platform. It really does work in my WindowsXP gvim, cygwin vim, MacOSX vim, and Ubuntu Dapper vim. Recently I installed Ubuntu Feisty and the feature seems to have gone (I installed vim-gnome version 7.0.135). Since I use the same .vimrc in all platform, it is unlikely to be the fault of my .vimrc script, the problem is I do not know how to debug vim script, and I don't know why that autocommand does not work. Restore cursor to file position in previous editing session : http://vim.sourceforge.net/tips/tip.php?tip_id=80 The command therein will return your cursor to the same line and column that it was in previously. Regards, Chip Campbell ### Re: is there a list-administrator ? Toon Knapen wrote: Is there a list-administrator also listening in ? I have tried to unsubscribe a zillion times now and I'm still on this list. I would appreciate if the ml-admin could help me out here. Somewhat modified version of what Tony M sent awhile ago... Unsubscribing from the vim or vim-dev list requires the following steps: 1. Send an email to the list you want off of: [EMAIL PROTECTED] -and/or- [EMAIL PROTECTED] That email does not need any body text, but its From: line must contain your subscribed address. The From: line must be the same as the one from which you subscribed and are receiving list mail! 2. Wait (usually a few seconds, sometimes a few minutes, depending on how often you fetch mail from your server) for a robot autoreply to the message you sent at step 1. 3. The robot autoreply (step 2) is there to check that the message (step 1) was really from you! It will contain instructions on how to complete the unsubscription. 4. Do what the autoreply says: this usually means sending an email to an address containing a complicated pseudorandom key, and acts as verification that its really you that wants to unsubscribe, not some prankster. 5. Shortly after you complete step 4, the list mail for this list should stop coming in. ### Re: question about insert mode and zz shawn bright wrote: Hey there all, i really dig the zz function to get me in the middle of the screen. i was wondering if there were an insert mode ability to do the same thing. So if i am writing a long function and get to the bottom of the screen i can move where i am at to the middle of the screen while still in insert mode? Others have covered various sorts of maps; however, if you really like having that cursor in the middle of the screen, I suggest setting the scrolloff option. ex. set scrolloff=999 will always keep the current line in the middle of the screen. If you like some wiggle room, try ex. set scrolloff=5 Regards, Chip Campbell ### Re: moving virual rectange about in virtualedit mode Yakov Lerner wrote: I 'set ve=all' and selected a rectangle with Ctrl-V. How can I move this rectangle up/down left/right with arrows ? With DrawIt v8d, you can move a selected rectangle about with your mouse. Here's the relevant portion of the help for DrawIt: ctrl-leftmouse One may drag and move a selection with ctrl-leftmouse. First, select the region using the leftmouse. Release the mouse button, then press ctrl and the leftmouse button; while continuing to press the button, move the mouse. The selected block of text will then move along with the cursor. Here's how to get install DrawIt (when 7.1 comes out, this will become lots easier - just steps 34) To get an up-to-date version of drawit, you'll also need to get an up-to-date version of vimball. So: 1) Get an up-to-date version of vimball: http://vim.sourceforge.net/scripts/script.php?script_id=1502 -or- http://mysite.verizon.net/astronaut/vim/index.html#VimBall (the mysite.verizon.net one will be the more recent version) 2) Remove the old vimball plugin and install the new one: Linux: cd /usr/local/share/vim/vim70 /bin/rm plugin/vimball.vim autoload/vimball.vim doc/pi_vimball.txt mv (wherever it was downloaded)/vimball.tar.gz . gunzip vimball.tar.gz tar -xvf vimball.tar Windows: Under Windows, check your runtimepath to determine where your vim 7.0's runtime directories are: vim :echo rtp :q The first directory is likely your personal plugins directory, the second one is your vim system directory. cd (to your vim system directory) del plugin\vimballPlugin.vim del autoload\vimball.vim del doc\pi_vimball.txt ren (wherever)\vimball.tar.gz vimball.tar.gz gunzip vimball.tar.gz tar -xvf vimball.tar 3) Get DrawIt: http://vim.sourceforge.net/scripts/script.php?script_id=40 http://mysite.verizon.net/astronaut/vim/index.html#DRAWIT 4) Install an up-to-date version of Drawit: vim DrawIt.vba.gz :so % :q ### Re: moving virual rectange about in virtualedit mode Gary Johnson wrote: On 2007-05-02, Charles E Campbell Jr [EMAIL PROTECTED] wrote: Yakov Lerner wrote: I 'set ve=all' and selected a rectangle with Ctrl-V. How can I move this rectangle up/down left/right with arrows ? With DrawIt v8d, you can move a selected rectangle about with your mouse. Here's the relevant portion of the help for DrawIt: ctrl-leftmouse One may drag and move a selection with ctrl-leftmouse. First, select the region using the leftmouse. Release the mouse button, then press ctrl and the leftmouse button; while continuing to press the button, move the mouse. The selected block of text will then move along with the cursor. Unfortunately, this works only for gvim, not vim. ctrl-leftmouse in an xterm opens the Main Options menu. Here's how to get install DrawIt (when 7.1 comes out, this will become lots easier - just steps 34) 3) Get DrawIt: http://vim.sourceforge.net/scripts/script.php?script_id=40 http://mysite.verizon.net/astronaut/vim/index.html#DRAWIT 4) Install an up-to-date version of Drawit: vim DrawIt.vba.gz :so % :q One may need to uninstall (i.e., delete) any earlier version of DrawIt, too, specifically the file ~/.vim/plugin/DrawIt.vim. The symptoms of needing to do this include vim complaining at startup that \di has been defined twice. I use the line-drawing capability of DrawIt all the time. I haven't done much with the visual-block commands, so I thought I'd try one. I think I found a bug in the version of DrawIt from the astronaut site. I inserted the following two paragraphs of text into a buffer, started DrawIt by typing \di, left-clicked the mouse on the character in the upper left corner of the region (the 'e' in everywhere, no longer visible below), dragged the visual selection to the lower right corner, and typed \b to draw a box. Mary had a little lamb, Its fleece was white as snow, And +--+ went, The \|amb was sure to go\| \|\| It f\|llowed her to scho\|l one day, Whic+--+le, And made the children laugh and play To see a lamb at school. Note that the two bars between the paragraphs are in columns 1 and 2 instead of 8 and 27. See DrawIt's help, lines 253-256. The visual-block commands require spaces to work in. Most of these commands are imported from Sylvain Viart's drawing.vim; I haven't tried making the holer routine obsolete yet. Regards, Chip Campbell ### Re: Gvim File Explorer error [EMAIL PROTECTED] wrote: After upgrading I now get Error detected while processing function MenuExplOpen: line4: E316: ml_get: cannot find line 9 Press ENTER or type command to continue E316: ml_get: cannot find line 9 Error detected while processing function SNR15_Highlight_Matching_Pair: line 17: E316: ml_get: cannot find line 9 My version was. ll /usr/share/vim/vim70/plugin/netrwPlugin.vim rw-r--r-- 1 root root 7713 2006-10-10 02:56 I have upgraded to, the problem exists still exists. rw-r--r-- 1 root root 7713 2007-01-31 19:23 Any idea where to start looking in the environment? my rtp=~/.vim,/var/lib/vim/addons,/usr/share/vim/addons,/usr/share/vim/vimfiles,/usr/share/vim/vim70,/usr/share/vim/vimfiles/after,/usr/share/vim/addons/after,/var/lib/vim/addons/after,~/.vim/after vim --version VIM - Vi IMproved 7.0 (2006 May 7, compiled Jan 31 2007 18:15:57) Included patches: 1-122 You need to upgrade vim itself; there was a patch (I'm afraid that I forget which one) which addressed the ml_get problem. Alternatively, you can try reading :help netrw-ml_get and see if the directions therein help. Regards, Chip Campbell ### Re: possible bug with vim7 and the arrow keys Viktor Kojouharov wrote: It turned out that these mappings broke the arrow keys in the terminal: inoremap expr Esc pumvisible()?\C-E:\Esc inoremap expr CR pumvisible()?\C-Y:\CR inoremap expr Down pumvisible()?\C-N:\Down inoremap expr Up pumvisible()?\C-P:\Up inoremap expr PageDown pumvisible()?\PageDown\C-P\C-N:\PageDown inoremap expr PageUp pumvisible()?\PageUp\C-P\C-N:\PageUp IMHO, if one is expecting to use vim (as opposed to gvim), mapping Esc causes trouble. That's because most terminals issue escape sequences (esc..something..) when special keys (such as the arrow keys, functions keys, etc), and that mapping of the esc key messes up the escape sequence. Besides -- how do you get out of insert mode? I realize one can use ctrl-o and norm!, but that seems painful. If you're not using normal mode or command mode, then you're missing a lot of vim. Regards, Chip Campbell ### Re: open remote file in vim/gvim ben lieb wrote: This might have been discussed before, but how can I open a file remotely in vim? Via, ftp, ssh, etc. vim ftp://host/path/to/file vim scp://host/path/to/file Both of these use the netrw plugin, BTW. Both may ask you for passwords, although one can work around that requirement (see :help netrw-listhack and :help netrw-password). Regards, Chip Campbell ### Re: What plugin is the one that does the following ... Andrew Falanga wrote: I'm doing some reading on vim.org in the documentation areas and found that the ability to browse a directory from within a buffer is actually accomplished by plugins rather than being built into the vim binary. I didn't know this. So, what plugin is it that accomplishes what is referenced here http://vimdoc.sourceforge.net/htmldoc/usr_22.html? netrw.vim Its also been updated quite a bit since the original release of vim 7.0; so here's some directions on how to update it: To get an up-to-date version of netrw, you'll also need to get an up-to-date version of vimball. So: 1) Get up-to-date versions of vimball and netrw: vimball: http://vim.sourceforge.net/scripts/script.php?script_id=1502 -or- http://mysite.verizon.net/astronaut/vim/index.html#VimBall (the mysite.verizon.net one will be the more recent version) netrw: http://vim.sourceforge.net/scripts/script.php?script_id=1075 -or- http://mysite.verizon.net/astronaut/vim/index.html#NETRW 2) Remove the old vimball plugin and install the new one: Linux: cd /usr/local/share/vim/vim70 /bin/rm plugin/vimball.vim autoload/vimball.vim doc/pi_vimball.txt mv (wherever it was downloaded)/vimball.tar.gz . gunzip vimball.tar.gz tar -xvf vimball.tar Windows: Under Windows, check your runtimepath to determine where your vim 7.0's runtime directories are: vim :echo rtp :q The first directory is likely your personal plugins directory, the second one is your vim system directory. cd (to your vim system directory) del plugin\vimballPlugin.vim del autoload\vimball.vim del doc\pi_vimball.txt ren (wherever)\vimball.tar.gz vimball.tar.gz gunzip vimball.tar.gz tar -xvf vimball.tar 3) Remove system version of netrw: Linux: cd /usr/local/share/vim/vim70 /bin/rm plugin/netrw.vim autoload/netrw.vim doc/pi_netrw.txt syntax/netrw.vim Windows: cd (to your vim system directory) del plugin\netrwPlugin.vim del autoload\netrw.vim del doc\pi_netrw.txt del syntax\netrw.vim 4) Install an up-to-date version of netrw: vim netrw.vba.gz :so % :q Regards, Chip Campbell ### Re: sh.vim - Syntax Highlighting Issues George wrote: I'd like to get the 'sh' filetype syntax highlighting working on FreeBSD. The following (supported) constructs, for example, show as errors. Read :help sh.vim and set one of the variables mentioned there in your .vimrc. Regards, Chip Campbell ### Re: Gvim File Explorer error [EMAIL PROTECTED] wrote: Occasionally when I press ALT+W,X I get some errors in the command line E316: ml_get: cannot find line 1 Press ENTER or type command to continue E316: ml_get: cannot find line 9 E316: ml_get: cannot find line 1 Press ENTER or type command to continue E316: ml_get: cannot find line 1 Press ENTER or type command to continue E316: ml_get: cannot find line 1 Press ENTER or type command to continue And the file window does not open successfully. I have to close the resulting window and the window from which I called it. Where is the corruption happening? What can I do to sanitize it? Is there a not somewhere about this? There used to be a problem with ml_get errors, so make sure you're up-to-date... vim has patches 1-224 netrwFileHandlers v9 netrwSettings v9 netrw v108 (v109a at my website) And now for notes on how to update: To get an up-to-date version of netrw, you'll also need to get an up-to-date version of vimball. So: 1) Get up-to-date versions of vimball and netrw: vimball: http://vim.sourceforge.net/scripts/script.php?script_id=1502 -or- http://mysite.verizon.net/astronaut/vim/index.html#VimBall (the mysite.verizon.net one will be the more recent version) netrw: http://vim.sourceforge.net/scripts/script.php?script_id=1075 -or- http://mysite.verizon.net/astronaut/vim/index.html#NETRW 2) Remove the old vimball plugin and install the new one: Linux: cd /usr/local/share/vim/vim70 /bin/rm plugin/vimball.vim autoload/vimball.vim doc/pi_vimball.txt mv (wherever it was downloaded)/vimball.tar.gz . gunzip vimball.tar.gz tar -xvf vimball.tar Windows: Under Windows, check your runtimepath to determine where your vim 7.0's runtime directories are: vim :echo rtp :q The first directory is likely your personal plugins directory, the second one is your vim system directory. cd (to your vim system directory) del plugin\vimballPlugin.vim del autoload\vimball.vim del doc\pi_vimball.txt ren (wherever)\vimball.tar.gz vimball.tar.gz gunzip vimball.tar.gz tar -xvf vimball.tar 3) Remove system version of netrw: Linux: cd /usr/local/share/vim/vim70 /bin/rm plugin/netrw.vim autoload/netrw.vim doc/pi_netrw.txt syntax/netrw.vim Windows: cd (to your vim system directory) del plugin\netrwPlugin.vim del autoload\netrw.vim del doc\pi_netrw.txt del syntax\netrw.vim 4) Install an up-to-date version of netrw: vim netrw.vba.gz :so % :q Regards, Chip Campbell ### Re: question about manpageview.vim version 16 Zhaojun WU wrote: Just found that after I updated the manpageview.vim plugin (http://www.vim.org/scripts/script.php?script_id=489) to the latest one, pressing K in some codes like printf(foo), when the cursor is under the word printf, will show me an error message like: *warning* sorry, no manpage exist for printf(. I browsed the change log of this plugin, the author, Dr. Chip, shifted back to use cWORD instead of cword to extract current WORD under cursor. So that, the printf(, not the expected printf, will be extracted out and will get NO match at all. Instead of modifying iskeyword to pick up a few more characters with cword, manpageview now uses cWORD and a substitute: let topic= substitute(a:1,'[^-a-zA-Z().0-9_].$','','') However, I think that the trailing '' should be 'g' instead... so I'll fix that. Chip Campbell ### Re: suggestion David Howland wrote: A.J.Mechelynck wrote: You mean if the buffer is displayed it would do nothing? No. Delete the buffer, but keep the window open. I often find myself in this situation: - Split window, two buffers open. - Open a new file, look at it, then want to close it. - i would expect to :bd to delete the current buffer, leaving the remaining two open, one for each window. But for some reason, it also removes my split. Why should deleting a buffer change how I have my splits set up? Because a window must always have a buffer to display. See Deleting a buffer without changing your window layout http://vim.sourceforge.net/tips/tip.php?tip_id=622 Regards, Chip Campbell ### Re: search-related question Hale Boyes, Kevin wrote: How do I search in a document to the next line that doesn't contain a specific string? Something along the lines of grep -v. I suggest trying the LogiPat plugin. To do what you're asking with it: :LP !string It takes Boolean logic (!=not \|=or =and ()s ) plus strings and constructs a regexp that'll do it. You can get the latest LogiPat.vim from http://mysite.verizon.net/astronaut/vim/index.html#LOGIPAT or a more stable version from: http://vim.sourceforge.net/scripts/script.php?script_id=1290 Regards, Chip Campbell ### Re: VIM doesn't need new features?!?! Peter Michaux wrote: And now I see that VIM doesn't need more features... http://www.vim.org/soc/ideas.php May I suggest taking a look at: Regards, Chip Campbell ### Re: Troubles configuring vim (multi-questions) OnionKnight wrote: Is it possible to make the cursor stay at it's position even after scrolling it out of view? Not at the current time. * At the beginning of an indented line, why does normal mode put the cursor at the end of the first tab whereas insert mode is position at the beginning of the line like I think it should? It's annoying to move around in code like that. I'm not entirely sure what you want here; does having set nosol * Is it possible to enter insert mode for files that aren't modifiable? Obviously any changes can't be saved but the buffer shouldn't be any problems to modify. set ma noro * Is it possible to close tabs with the middle mouse button? Try mapping it; put the following into your .vimrc: nmap middlemouse :tabccr * I wanted the Home-button to act so that it first jumps to the first non-whitespace character of the current line (i.e. skip the indentation) and if Home is pressed when you're already at the first non-whitespace character or before then it should jump to the real beginning of the line, column #1. function! HomeKey () let c = col(.) if c == 1 w else g0w if col(.) = c g0 endif endif endfunction You're getting your modes confused. If that if, for example, was executed in normal mode, it would enter insert mode and insert an f character. However, its in command mode; and that w is being executed in command mode, too (and it means write the file). Try using norm! w instead. Likewise with the g0w : norm! g0w etc. * In gvim, is it possible to have a drag-and-drop action open the dragged file into a new tab instead of a new buffer? Using the menu is just tedious, and you can't select multiple files either. Can't answer that -- I never use the mouse to drag-and-drop. Even if you set up some autocmds to do this, if you drop the same file onto vim you'll still get extra tabs unless your code sweeps through all the tabs and checks for a name match first. * I want to check a string if it begins with something but I have no clue why. I was thinking of a regexp but the only way to use matching regexps is for highlights and substition regexps seems to operate on the whole file or a selection and no way to use them on strings. Regexp's have nothing in particular to do with highlights. One can set 'hls' mode and get matches to show up, but that's like saying I want to build a cupboard but wood is always used to build houses. Substitutes act over specific ranges: :7,10s/abc/def/ will only change lines 7-10, not the whole file. By string, do you mean something with double-quotes? Just search for it: /BEGINNING_OF_STRING Regards, Chip Campbell ### Re: remote-silent and stdin [EMAIL PROTECTED] wrote: Mahesh Sivasubramanian/Lex/Lexmark 04/11/2007 10:57 AM To Yakov Lerner [EMAIL PROTECTED] cc vim@vim.org Subject Re: remote-silent and stdin Sorry I wasn't clear last time. I am trying to redirect the output of stdin to a remote client(not necessarily ls). Like if I want to do a cat file \| gvim --remote-silent . Its looks like -remote-silent takes in only files as arguments. And its documented, too: --remote [+{cmd}] {file} ...--remote Open the file list in a remote Vim. When there is no Vim server, execute locally. There is one optional init command: +{cmd}. This must be an Ex command that can be followed by \|. The rest of the command line is taken as the file list. Thus any non-file arguments must come before this. You cannot edit stdin this way \|--\|. The remote Vim is raised. If you don't want this use vim --remote-send C-\C-N:n filenameCR --remote-silent [+{cmd}] {file} ...--remote-silent As above, but don't complain if there is no server and the file is edited locally. Note the line that says You cannot edit stdin this way. Regards, Chip Campbell ### Re: syntax/man.vim: manSubHeading is a bit too general? Ian Tegebo wrote: On 4/9/07, Nikolai Weibull [EMAIL PROTECTED] wrote: syn match manSubHeading ^\s\{3\}[a-z][a-z ][a-z]$This will, however, match more lines than I think is intended. It will, for example, match the line \t returns are what are recorded and compared with the data git keeps where \t is a horizontal tabulation. I'm guessing that the actual regex should be ^ \{3\}[a-z][a-z ][a-z]$ I hope nobody minds if I take this opportunity to ask a question about vim's pattern matching. After reading \|pattern\| I wonder if the following is more efficient: syn match manSubHeading '^ \{3\}\l\l\?\l$' (snip) The pattern you've provided isn't matching the same thing. The current one: start the line with exactly three spaces or tabs, followed by a lower case character, followed by any number of lower case characters or spaces, up to a lower case character at the end-of-line. example: spacetabspace aaa aa Nikolai W's modifies that to start the line with exactly three spaces; the rest is the same. example: spacespacespaceaaa aa aaa Yours: start the line with exactly three spaces, followed by two or three lower case characters, which then terminates the line. example: spacespacespaceaa Do people find this to make a different for moderate file sizes, e.g. the man page for 'less' being ~2000 lines? Depends on the line lengths. Your pattern would terminate quite quickly on each line, as only 5 or 6 characters may be at the beginning of matching lines; anything more is a mismatch. The original and NW's both examine the entire line; so if every line had 1GB of characters, these two patterns would take considerably longer than yours. Regards, Chip Campbell ### Re: syntax/man.vim: manSubHeading is a bit too general? Nikolai Weibull wrote: On 4/9/07, Charles E Campbell Jr [EMAIL PROTECTED] wrote: In this case, by looking at syntax/man.vim, its: Gautam H. Mudunuri gmudunur AT informatica.com. Actually, this was actually the wrong maintainer. Gautam was the previous maintainer of this file. Nam SungHyun [EMAIL PROTECTED] maintains it now. Whoops -- yes, you're quite right. Sorry 'bout that... Chip Campbell ### Re: Fwd: Perl colour coding bug Jon Combe wrote: The following snippet of code, when saved with a .pl file extension breaks the colour coding in Vim #!/usr/bin/perl -w my$surname = ABC-DEF GHI; @split = split ( / \|-\|\/\|\/ , $surname , -1 ); foreach ( @split ) { print$_\n; } The lines after the split (that contains a regular expression) are highlighted as if they are within a double quoted string. The colour coding is being confused by the character in the regular expression and thinks (incorrectly) that it marks the start of a string. Is it possible to fix this problem? For example the foreach text should appear in yellow. The maintainer for perl is: Nick Hibma n_hibma AT van-laarhoven.org; he's the appropriate contact for this sort of thing. I found his name in vim70/syntax/perl.vim; syntax file maintainers generally put their contact information in the syntax file they maintain. Regards, Chip Campbell ### Re: How to recognize a single line via regexs Informationen wrote: Hi, how can I identify a single line no longer than e.g. 60 characters preceded and followed by a blank line via regexs. This way I want to identify section headings. What I did was mark every blank line with %s/^$// and than chomp the CR %s/\n//g and if the text between the 's isn't longer than 60 characters put it into \section{}, and replace every with \r\r. But in larger files this takes a while. Is there a smarter solution to the problem? The following regexp will do the match: ^\n\zs.\{1,60}\ze\n$ ^ beginning of line \n newline \zs pattern really starts here (but must be precededed by the foregoing) .\{1,60} one to sixty characters \ze pattern really ends here (but must be followed by the trailing pattern) \n newline $end-of-line Please read: :help regexp for (much) more. Regards, Chip Campbell ### Re: Help on search and replace Dudley Fox wrote: Hello Vim List, I have used vim for a while, and though no expert I am fairly comfortable with the common commands. Recently I ran into a situation where I just couldn't find a way to do a search and replace. I was hoping some of you experts could help me out. Starting text: nameTable[pattern with spaces0] = (pattern with spaces0, 12345) nameTable[pattern with spaces1] = (pattern with spaces1, 67890) nameTable[pattern with spaces2] = (pattern with spaces2, 243) nameTable[pattern with spaces3] = (pattern with spaces3, 421) nameTable[pattern with spaces4] = (pattern with spaces4, 3455) nameTable[pattern with spaces5] = (pattern with spaces5, ) Desired Text: nameTable[patternwithspaces0] = (pattern with spaces0, 12345) nameTable[patternwithspaces1] = (pattern with spaces1, 67890) nameTable[patternwithspaces2] = (pattern with spaces2, 243) nameTable[patternwithspaces3] = (pattern with spaces3, 421) nameTable[patternwithspaces4] = (pattern with spaces4, 3455) nameTable[patternwithspaces5] = (pattern with spaces5, ) Notice that the only difference is that the spaces are removed from the pattern in between the square brackets. I think I want to use \zs and \ze, but I couldn't wrap my head around the syntax. Any help would be appreciated. In addition to the various regexp solutions you've been given: if what you want done is actually contiguous linewise as shown, then vis.vim makes it fairly straightforward (http://mysite.verizon.net/astronaut/vim/index.html#VIS or http://vim.sourceforge.net/scripts/script.php?script_id=1195): select pattern with spaces0 ... pattern with spaces5 using ctrl-v and motion. :B s/ //g Regards, Chip Campbell ### Re: syntax/man.vim: manSubHeading is a bit too general? Nikolai Weibull wrote: The manSubHeading is defined as syn match manSubHeading ^\s\{3\}[a-z][a-z ][a-z]$ This will, however, match more lines than I think is intended. It will, for example, match the line \t returns are what are recorded and compared with the data git keeps where \t is a horizontal tabulation. I'm guessing that the actual regex should be Regards, Chip Campbell ### accounts and wikis Hello! In order to prevent spam, some sort of verification procedure seems to be necessary. Vim's website already supports accounts; would requiring one to log into a vim account before making tips or add-ons to tips help? A verification step for account privilege (apply for account - mail to user with magic cookie - user mails magic cookie back) should serve to ameliorate spam, I'd think, although it'd still be possible. Regards, Chip Campbell ### Re: Searching within a delimited area Afton Lewis wrote: How would I search for a regex within a particular area? The text document is very long, and I don't want to match all instances, just those I care about. I would probably select the text visually. With vis.vim, a plugin available from: http://mysite.verizon.net/astronaut/vim/index.html#VIS or a more stable version from: http://vim.sourceforge.net/scripts/script.php?script_id=1195 you may use visual mode (either line, character, or block; ie. either with V, v, or ctrl-v) to select a region, then use :S regexp and the search will only pick up items in that region. Regards, Chip Campbell ### Re: Number Changes Mike Blonder wrote: Hi. I periodically need to make changes to a script built with tab delimited values. What I need to do is, from time to time, to either add 1 to a value or to subtract 1 from the same value. Typically the script looks like: ln 1 $10 != { printf ((moodlook$10 } ln 2 $11 != { printf ((feeloil$11 } ln 3 $12 != { printf ((eyeflavor$12 } . . . Is there an alternative to manually CTRL-A'ing each line twice to change ln 1, for example, to #11 != { printf ((moodlook 11 } If these numbers are in columns (and you did say tab-delimited, so perhaps they are), then visincr.vim may be helpful. With the visincr.vim plugin: Change number in upper left hand corner to what you want it to be. ctrl-v to begin visual block mode with the upper left hand corner of column of numbers move cursor to lower right hand corner of column :I This process will change one column of numbers. You can get visincr from: http://mysite.verizon.net/astronaut/vim/index.html#VISINCR or from http://vim.sourceforge.net/scripts/script.php?script_id=670 Quick overview: :I[#] left justified incremented list :II [# [zfill]] right justified incremented list :IO [#] left justified octal incremented list :IIO [# [zfill]] right justified octal incremented list :IX [#] left justified hex. incremented lsit :IIX [# [zfill]] right justified hex. incremented lsit :IYMD [# [zfill]] year/month/day incremented list :IMDY [# [zfill]] month/day/year incremented list :IDMY [# [zfill]] day/month/year incremented list :IA [#] alphameric incremented list :ID [#] dayname incremented list :IM [#] monthname incremented list And, if your columns of numbers aren't aligned, but you'd like them to be, check out Align.vim (available at my website, too). Regards, Chip Campbell ### Re: Optimum syntax file size... Robert Hicks wrote: Is there a size limit that one should set as a ceiling for syntax file size? Engspchk uses some rather large syntax files for its dictionary. Especially if you're using keywords, syntax file size isn't likely to be a problem. Regards, Chip Campbell ### Re: vim console? John Doe wrote: How to control the vim 'console' from programs like the tetris and other games written for vim? Of course, I could look in the source, but am confused from it? Are there multiple ways to accomplish this? I don't see any other replies, so here goes: I'm not sure what you're asking. Every game has its own methods for controlling itself. Mines.vim, for example, provides both keyboard and mouse interaction. So, I suggest reading whatever help comes with the game. Regards, Chip Campbell ### Re: vim console? John Doe wrote: Oh, thank you for your reply: I wanted to know how to _program_ the vim 'console', from a script: the general direction on how to do it: I know how to obtain the number of columns and rows, but how about how to write a specific char to a specific location, also is it possible to access the Internet from a script, just as it's possible from awk, for example. Anything you can type from the command line can go into a script. Anything you type in normal mode can be typed from a command line; see :help :norm Hence anything from normal mode can also go into a script (just use norm). I'm not sure about what you mean by obtaining the number of columns and rows. How to write to a specific location: there are several ways, but one is: linewise : call setline(lnum,new line goes here) lnum is an integer writing a character to a specific column in a specific line: (replacing in line #lnum, column# colnum, with character X) lnum put line number in instead of lnum colnum\| put column number in instead of colnum norm! rX Accessing the internet is possible, see :help :! and :help system() . Alternatively, you may use netrw's url format: r scp://hostname/path/to/a/file w ftp://hostname/path/to/a/file so scp://hostname/path/to/a/file Regards, Chip Campbell ### Re: pulling text to the right? Kim Schulz wrote: I just tested it to see if I could get it to work, but I have some problems. I inserted the following int foo; uint8_t bar; TIME baz; int hello=world; and then followed you instructions (used \tsp), but the result afterwards is: int foo; uint8_t bar; TIME baz; int hello=world; What I got with your example: int foo; uint8_t bar; TIMEbaz; int hello=world; So everything lined up. Of course, when I used my mouse to pick up your text, it was composed of all spaces. Does your original happen to have a mixture of tabs and spaces? Besides, this text is looking rather like a declaration set. There's a map specifically supporting that: \adec Regards, Chip Campbell ### Re: Sorting a .bib file Vincent Beffara wrote: So here is my question. I have a bibliography in a .bib file, which (just in case) is just a plain text files containing entries that each look like this : @article{key, author = {Whatshisname, J.}, title = {My paper} } (note the '@' at the beginning of the first line - folding a .bib file is trivial for instance). I would like to sort the entries according to, say, the author's last name (though by key or even by first line is ok). What would be a good way to do this ? Sure! The approach I'm suggesting uses BlockSort(), available as part of the vissort plugin. You can get the vissort plugin from my website: http://mysite.verizon.net/astronaut/vim/index.html#VISSORT Here's the relevant blurb from the help: :','BS :' 'BS nextblock endblock findtag tagpat tagsub :[range]call BlockSort(nextblock,endblock,findtag,tagpat,tagsub) :[range]call BlockSort(...) If any arguments are missing, BlockSort() will query the user for them. This function's purpose is to sort blocks of text based on tags contained within the blocks. For this particular problem, the following call will work: %call BlockSort('[EMAIL PROTECTED]','','^\sauthor\s=','^.{\s$$.\{-}$$\s,.','\1') This assumes: each block starts, at the beginning of the line, @article This pattern is also used to separate blocks. Inside the block is a line satisfying the pattern: ^\sauthor\s= The next two items are used in a substitute operation on the line satisfying the pattern above, and are used to extract the item that the blocks are to be sorted with. Regards, Chip Campbell ### Re: tips project Tom Purl wrote: There is one thing to mention about parsing tips. Are we going to put there are also many useless junk. It would be _lots_ of work to look at every comment and see if they're useful or not. This is a really good question. Here's my opinion. The comments are* a necessary part of the tip, and should be included with the import. In general, I would like to move 100% of the content from the tips on the vim.org web site to the wiki, even if some of the data doesn't fit very well into the wiki. After that, the tips information can be refactored as necessary by the community. its output files; plus ratings. I'm not sure how one might want to do ratings in the future, though. Here's one quick idea... each tip includes ratings to change a tip's rating, click on a link for one of the three selections. The link updates a database similarly to what is done now and modifies the tip page to reflect the new rating. I bring this up because the change-rating gadget is missing from at least my script's output, and if a mechanism can be agreed upon the script could include that mechanism. Regards, Chip Campbell ### Re: Help needed to : Start on the line where I left when I opened the file last time I just need some help on vim configuration. Let say the file is good.text. I open the file and goto 66 line and come out by typing :wq in escape mode. Now, when I open it again, my cursor is placed in line 0. I want it to be placed in line 66. I am facing this problem in my Solaris 10 x86 machine. The same thing is working fine in Linux. feature. [I have tried Google search and could not get useful links]. Restore cursor to file position in previous editing session. HTH, Chip Campbell ### Re: Insert mode and arrow keys philosophy Pavel Shevaev wrote: On 2/21/07, DervishD [EMAIL PROTECTED] wrote: Hi Laurent :) Unfortunately, I still have problems using 'h' :( That's my biggest problem at the moment as well, as a blind typer i can't get used to it...oh, i think i just should stop whining and exercise more ;) I think I understand the issue; one sort of expects to use a different finger for each motion. I've sort of gotten used to shifting my right hand one key to the left when I intend to move the cursor, thus I get right index finger == h right middle finger == j right ring finger == k right little finger == l Of course, that means whenever I use OtherEditors, such as with certain mail clients, I end up with jjkkllhhh#)() sequences :O . Regards, Chip Campbell ### Re: surround.vim in AsNeeded Bill McCarthy wrote: BTW, as an enhancement request, could AN be enhanced to look for leadermap when it fails to find charmap? That is, if I want to load the align maps: AN \abox doesn't work. I would need to type: If you happen to have (as an example) in your .vimrc, did you know that :AN ;abox just the leader you're actually currently using. Regards, Chip Campbell ### Re: Overview of diretories of $HOME/.vim Kai Weber wrote: where can I find an overview of the$HOME/.vim directory hierarchie? I documentation for :help ftplugin, :help initialization and so on. snip Hello! I have the following help file which I use; see attached. Place it in: .vim/doc Bring up vim, type: :helptags ~/.vim/doc Regards, Chip Campbell dotvim.txtThe .vim Directory StructureFeb 20, 2007 .vim-after.vim-ftplugin .vim-plugin .vim-doc .vim-indent .vim-syntax The VIM LICENSE applies to dotvim.vim and dotvim.txt No warranty, express or implied. Use At-Your-Own-Risk. == 1. The .vim/ directory tree .vim vimfiles The user's local plugins and whatnot are stored under: .vim/ Unix vimfiles/ PC,Mac filetype.vim\|new-filetype\| new filetypes triggered by filename scripts.vim \|new-filetype-scripts\| new filetypes triggered by file contents after/compiler/ \|write-compiler-plugin\| overrule a compiler plugin after/filetype.vim \|43.2\| overrule filetype after/ftplugin \|ftplugin-overrule\| after/plugin user-specified additions to pre-existing syntax highlighting ex. after/syntax/c.vim Starting with vim 7.0, scripts can be broken into an colors/ \|:colorscheme\| holds colorscheme files compiler/ \|:compiler\| holds compiler files put in your own help files such as this one ftdetect/ \|new-filetype\| \|plugin-filetype\| Filetype detection scripts. Note that: set filetype=foo overrules setf foo sets filetype only when not set yet ftplugin/ \|write-filetype-plugin\| filetype-based plugins (ex. ftplugin/tex/tex.vim) indent/ \|filetype-indent-on\| \|indent-expression\| user-specified indenting associated with syntaxfile.vim keymap/ \|mbyte-keymap\| specify keymap files (multibyte related) plugin/ \|write-plugin\| \|filetype-plugins\| \|plugin-special\| files herein will be loaded automatically at every invocation of vim syntax/ \|mysyntaxfile\| \|new-filetype\| new user-specified syntaxfile.vim files holds dictionaries of words for spell checking systags \|ft-c-omni\| May be used to help complete system functions tutor/ \|tutor\| files for vimtutor .vim/after - vim:ts=8:tw=78:ft=help Bin Chen wrote: Can VIM configured to reload the opened file in a constant interval? Not easily; there's no such configuration options. However, I suspect that there may be two if not more ways to do this: * use an outside process on a multitasking o/s to ping vim using remote_send() would likely work * possibly something can be done with libcall() Regards, Chip Campbell ### Re: Enabling gvim? [EMAIL PROTECTED] wrote: I d/l'd and cofigured vim7.x (latest) as follows... ./configure --prefix=/vimpath --enable-gui Should this enable gvim? I did a make install, and cd /vimpath/bin ln -s vim gvim When I start gvim, I get E25: GUI cannot be used: Not enabled at compile time What do I need to do to use gvim? Are you using windoze, linux, or mac? For windows: what compiler are you using? For example: cygwin: make -f Make_cyg.mak M$visual c: make -f Make_mvc.mak etc. So, it depends on what compiler you're using as to which makefile to use. You can then edit the appropriate makefile for particular options you want. Generally, though, they do come up with gui (gvim). For linux: I use configure --with-features=huge --enable-perlinterp make su make install I've not used the Mac... I suggest trying to get the compile to work as shown above first, and then try again with whatever configure options you want. Make sure that the usual way works first! Regards, Chip Campbell ### Re: search command in visual mode - how to? Sibin P. Thomas wrote: Hi all, I am stuck in one of my scripting attempts! The context : Suppose I want to delete the string bio from the following line The biosphere is huge and I want to do it in this way - /biosCR vCR //eCR dCR Now I want to do the same thing, but conditionally...basically I want to use the :if construct. I tried - :if (@0=~something) \| exe /bios \| exe normal v \| exe //e \| endif This where I am stuck; I am not able to reproduce the effect of //eCR through the :if construct. In this case I get the error e481: No range allowed and if I try - exe normal //e it just stays in visual mode doing nothing. Can anyone help me out here? This is going to play a huge part in most of my scripts! Several notes 1. exe /bios might fail. You probably should use the search() function: if search('bios') ... endif 2. bios might be part of a word (example: symbiosis) and get found when you don't want it to be. Perhaps search('\bios') would be better? 3. Why not do the search substitute directly from ex? /\bios/s/// 4. If for some odd reason you feel you absolutely must use visual mode for this, then try exe norm! v//e\crd Regards, Chip Campbell ### Re: vim return code Martin Krischik wrote: Hello, I often use little vim scripts using vim -E. Now like all executable vim will return a result code after execution. And it is often false which I don't want. Does anybody know how to influence the return value from vim -E? :q :wq :q! -- these are normal quits (:wq also writes) :cq -- quits, but Vim will return an error code HTH, Chip Campbell ### Re: 7.0.188 - problem with directory browser? Denis Perelyubskiy wrote: in version 7.0.188 (I am on windows xp, us) nothing works when I select '..' when browsing a directory. has anyone seen this? is this something peculiar to my installation, a bug, or a feature? I suspect that you need a recent version of netrw. To get an up-to-date version of netrw, you'll also need to get an up-to-date version of vimball. So: 1) Get up-to-date versions of vimball and netrw: vimball: http://vim.sourceforge.net/scripts/script.php?script_id=1502 -or- http://mysite.verizon.net/astronaut/vim/index.html#VimBall (the mysite.verizon.net one will be the more recent version) netrw: http://vim.sourceforge.net/scripts/script.php?script_id=1075 -or- http://mysite.verizon.net/astronaut/vim/index.html#NETRW 2) Remove the old vimball plugin and install the new one: Linux: cd /usr/local/share/vim/vim70 /bin/rm plugin/vimball.vim autoload/vimball.vim doc/pi_vimball.txt mv (wherever it was downloaded)/vimball.tar.gz . gunzip vimball.tar.gz tar -xvf vimball.tar Windows: Under Windows, check your runtimepath to determine where your vim 7.0's runtime directories are: vim :echo rtp :q The first directory is likely your personal plugins directory, the second one is your vim system directory. cd (to your vim system directory) del plugin\vimballPlugin.vim del autoload\vimball.vim del doc\pi_vimball.txt ren (wherever)\vimball.tar.gz vimball.tar.gz gunzip vimball.tar.gz tar -xvf vimball.tar 3) Remove system version of netrw: Linux: cd /usr/local/share/vim/vim70 /bin/rm plugin/netrw.vim autoload/netrw.vim doc/pi_netrw.txt syntax/netrw.vim Windows: cd (to your vim system directory) del plugin\netrwPlugin.vim del autoload\netrw.vim del doc\pi_netrw.txt del syntax\netrw.vim 4) Install an up-to-date version of netrw: vim netrw.vba.gz :so % :q Regards, Chip Campbell ### Re: BOF Vim 8 - EncryptLine Matthew Winn wrote: Text editors don't do encryption and never should. How else would you ensure that you can have encrypted text _without_ the need to temporarily store a plaintext copy of the file? Pipe the text through to an external encryption tool, such as pgp. Assuming your o/s supports true pipes... Chip ### for vim v8: how about keepundo ? The idea would be to leave the undo list alone, so that when the undo table gets updated next it'll have a bigger change. Regards, Chip Campbell ### Re: for vim v8: how about keepundo ? Nikolai Weibull wrote: On 1/29/07, Charles E Campbell Jr [EMAIL PROTECTED] wrote: The idea would be to leave the undo list alone, so that when the undo table gets updated next it'll have a bigger change. What do you mean? From the very short description it sounds like your describing :undojoin. A keepundo would be more akin to the keepjumps, keepalt style of suppressing some update for the command which follows. Regards, Chip Campbell ### Tip karma storms Hello! The following is a note that I sent to Scott Johnston; perhaps people have woken up and decided in large groups that they really like my tips, :) but: For the third time since January 15, I've seen tip storms in karma rating changes. Here's the latest one (Jan 22, 2007): Karma/Raters/Downloads: dK/dR/ dD: K / R / D tip changed by 20/ 5/ 17: 96/ 33/5988 How to initialize plugins (avg_karma=2.9 R/D= 0.55%) tip changed by 20/ 5/ 15: 145/ 47/3837 A map for swapping words (avg_karma=3.1 R/D= 1.22%) tip changed by 20/ 5/ 47: 142/ 58/12779 Highlight matching brackets as one moves in normal mode (plugin)(avg_karma=2.4 R/D= 0.45%) tip changed by 40/10/ 40: 236/ 79/12849 Using vim as a man-page viewer under Unix (avg_karma=3.0 R/D= 0.61%) tip changed by 24/ 6/ 17: 74/ 22/4680 Spelling checkers for: Dutch, English, German, Hungarian, and Yiddish(avg_karma=3.4 R/D= 0.47%) tip changed by 1/ 1/ 55: 398/135/8246 Restore cursor to file position in previous editing session (avg_karma=2.9 R/D= 1.64%) tip changed by 16/ 4/ 12: 127/ 38/6674 Applying substitutes to a visual block (avg_karma=3.3 R/D= 0.57%) script changed by 2/ 2/ 1: 391/296/1776 visincr.vim (avg_karma=1.3 R/D= 16.67%) tip changed by 36/ 9/ 33: 167/ 54/6999 How to sort using visual blocks (avg_karma=3.1 R/D= 0.77%) tip changed by 24/ 6/ 9: 56/ 16/3310 Opening gvim atop a console window (avg_karma=3.5 R/D= 0.48%) tip changed by 20/ 5/ 10: 69/ 23/1488 How to overwrite a visual-block of text with another such block (avg_karma=3.0 R/D= 1.55%) This records changes in karma since last Friday. I usually get 2 or 3 tip+script karma changes a day, but the same 2 or 3 changes on weekends. I saw this last Monday and last Wednesday, too. I sent a note to Bram: - I've noticed twice now a large number of my tips have received a lot of increase in ratings. As an example: (change-in-karma/qty-raters/qty downloads/viewers : total karma/raters/viewers) tip changed by 12/ 3/ 16: 76/ 28/5971 How to initialize plugins (avg_karma=2.7 R/D= 0.47%) tip changed by 12/ 3/ 11: 125/ 42/3822 A map for swapping words (avg_karma=3.0 R/D= 1.10%) tip changed by 12/ 3/ 36: 122/ 53/12732 Highlight matching brackets as one moves in normal mode (plugin)(avg_karma=2.3 R/D= 0.42%) tip changed by 20/ 5/ 21: 196/ 69/12809 Using vim as a man-page viewer under Unix (avg_karma=2.8 R/D= 0.54%) tip changed by 16/ 4/ 11: 50/ 16/4663 Spelling checkers for: Dutch, English, German, Hungarian, and Yiddish(avg_karma=3.1 R/D= 0.34%) tip changed by 8/ 2/ 13: 111/ 34/6662 Applying substitutes to a visual block (avg_karma=3.3 R/D= 0.51%) script changed by 2/ 2/ 1: 388/293/1774 visincr.vim (avg_karma=1.3 R/D= 16.52%) tip changed by 20/ 5/ 29: 131/ 45/6966 How to sort using visual blocks (avg_karma=2.9 R/D= 0.65%) tip changed by 12/ 3/ 6: 32/ 10/3301 Opening gvim atop a console window (avg_karma=3.2 R/D= 0.30%) tip changed by 12/ 3/ 5: 49/ 18/1478 How to overwrite a visual-block of text with another such block (avg_karma=2.7 R/D= 1.22%) script changed by 4/ 1/ 68: 39/ 12/ 617 LargeFile.vim (avg_karma=3.2 R/D= 1.94%) Consider the Spelling checkers for: Dutch, English, ...: that tip has been pretty much out-of-date for several years due to improvements in Engspchk, and even more so now with vim 7.0's built-in spelling checker. I have a record of karma changes to this tip: 08/07/03 tip 19/ 7/1336: Spelling checkers for: Dutch, English, German, Hungarian, and Yiddish 11/24/03 tip 18/ 8/1601: Spelling checkers for: Dutch, English, German, Hungarian, and Yiddish 01/16/07 tip 34/ 12/ 4652: Spelling checkers for: Dutch, English, German, Hungarian, and Yiddish 01/18/07 tip 50/ 16/ 4663: Spelling checkers for: Dutch, English, German, Hungarian, and Yiddish You can see that only two people changed its rating since Aug 7, 2003, except for this week, where there was substantial increases twice in one week. I often do the check on ratings every two or three days. - I noticed this karma-increase-storm for a bunch of other tips, too. I figure either its a vandal or perhaps the tip-note cleaning process has a bug affecting karma ratings. If its a vandal, I have no idea what can be done about it, but I thought I'd pass the info along. He suggested I let you know. ### Re: patch 182 and selectbuf [interferes with netrw plugin] Denis Perelyubskiy wrote: Thanks. While I can't tell what went wrong by just eye-balling the patches, I did find that the problem results from netrwPlugin.vim. Basically, netrw registers this autocommand: au BufEnter . silent! call s:LocalBrowse(expand(amatch)) When it is executed on a buffer switch, sometimes this amatch is emty. I've no idea why. If I remove the netrw plugin, things go back to normal. I did notice that netrw plugin changed recently... Can you give me an example? Also, what o/s are you using? The s:LocalBrowse() function checks if the name passed to it is a directory. Except for the Amiga, an empty string should be getting ignored (isdirectory() is zero). Regards, Chip Campbell ### Re: Tips which have spam contained in their comments/notes: Yongwei Wu wrote: On 1/18/07, Charles E Campbell Jr [EMAIL PROTECTED] wrote: FYI -- this is a list of my tips that still have link spam added as comments/notes: I'm sure that they're not the only ones. It is really annoying. In the worst case, there are 12 spam notes in a tip! I needed to click and wait for quite a while because of the Internet problem caused by the Taiwan earthquake. At least the spam notes in these tips are eradicated now. Thank you! It almost feels like taking a shower after one really needs one... Regards, Chip Campbell ### Re: Modifying the tag stack Alpt wrote: On Thu, Jan 18, 2007 at 08:15:37AM -0500, Ross A. Osborn: ~ On Thu, Jan 18, 2007 at 01:58:40PM +0100, Alpt wrote: ~ ~ How is it possible to push something in the tag stack without jumping? ~ ~ Would mapping the combination of CTRL-TCTRL-O do what you want? No, because the user has to always use C-T and C-] to jump back and forward. From the user point of view, jumping on [[file.c:45]] must be the same of jumping on [[TAG]]. The internal difference is that the jump on [[file.c:45]] equals to :e +45 file.c' Hello! Perhaps something along the lines of save current user position/buffer (see :help getpos()) :exe keepjumps ta .expand(cword.) :return to saved user position buffer (but use keepjumps) (see :help setpos()) This should put the cword onto the tagstack, but the keepjumps will keep the jumplist untainted. Wrap it all up into a map/function/command, and I think you'll have your solution. Regards, Chip Campbell ### Tips which have spam contained in their comments/notes: Hello! FYI -- this is a list of my tips that still have link spam added as comments/notes: 126 139 147 150 152 167 200 411 573 588 607 622 744 862 895 I'm sure that they're not the only ones. Regards, Chip Campbell ### Re: enclosing a visual block with quotes Bram Kuijper wrote: anybody a solution to easily enclose parts of text using visual mode? You can get the latest vis.vim from http://mysite.verizon.net/astronaut/vim/index.html#VIS or a more stable version from: http://vim.sourceforge.net/scripts/script.php?script_id=1195 and use it as follows: v (move) :B s/\_.\ze\n// That'll put double quotes around the character-oriented visual selection. Regards, Chip Campbell ### Re: .vimrc from URL A.J.Mechelynck wrote: Charles E Campbell Jr wrote: OK, with all that: vim -U NONE -c set nocp\|so$HOME/.vim/plugin/netrwPlugin.vim -c so scp://HOSTNAME/.vimrc Rather than -U NONE (i.e., no gvimrc) shouldn't that be -u NORC (i.e., with small u: don't source $HOME/.vimrc but do source the global plugins)? I suggest the amended command-line below (with --cmd for early sourcing): vim -u NORC -N --cmd runtime plugin/netrwPlugin.vim --cmd source scp://HOSTNAME/.vimrc Sounds better! I'll put a note to that effect in pi_netrw.txt. Regards, Chip Campbell ### Re: vim \| deleting end of lines inside a pattern Nikolaos A. Patsopoulos wrote: Hi, I would like to delete all end of lines (\n) inside a given pattern that runs through a text. The pattern is like this: PubmedArticle text1 \n text2 \n text3 \n text4 \n text5 \n text6 \n ... \n PubmedArticle Does :%s/PubmedArticle\_.\{-}\zePubmedArticle/PubmedArticle\r/g do what you want? I suggest that you read :help regexp Regards, Chip Campbell ### Re: Defining settings based on file ext/type. Ramashish Baranwal wrote: Hi, I would like to know how to define file specific settings (based on file extension/type). I would prefer modifying my .vimrc file instead of language specific .vim files. I am trying to achieve something like- if file-extension is .c or .cpp # expand tabs to spaces set sw=4 ts=4 expandtab else if filetype is Makefile # don't expand tabs to spaces noexpandtab endif Any help would be appreciated. :) Your example seems to indicate that you want to take actions based upon file specific settings, not how to define new ones. The proper way to do this: vim (home)/.vim/ftplugin/c.vim # expand tabs to spaces set sw=4 ts=4 expandtab :wq vim (home)/.vim/ftplugin/make.vim # don't expand tabs to spaces noexpandtab :wq Now, if you insist on doing something similar in your .vimrc instead of the proper way... au FileType .c,.cpp,.cxx,.h,.hpp set sw=4 ts=4 expandtab au FileType makefile,Makefile set noexpandtab All of this is untested, BTW. Suggested reading: :help autocmd :help FileType :help ftplugin Regards, Chip Campbell ### Re: grouping problem Nikolaos A. Patsopoulos wrote: Ηι, I'm want to group a text that has the following text pattern (values and number of lines vary across instances): PMID16893921/PMID Volume164/Volume Issue7/Issue Year2006/Year ISOAbbreviationAm. J. Epidemiol./ISOAbbreviation ArticleTitleImplications of small effect sizes of individual genetic variants on the design and interpretation of genetic association studies of complex diseases./ArticleTitle MedlinePgn609-14/MedlinePgn FirstAuthorIoannidis JP Used the following code but got a pattern recognition problem.: :%s/$$PMID.$$$$Volume.$$$$Issue.$$$$Year.$$$$ISO.$$$$ArticleTitle\_.\{-}ArticleTitle$$$$MedlinePgn.$$$$FirstAuthor.$$/\1\6\5\4\2\3\7\8\g What am I missing?? %s/$$PMID.$$\n\+$$Volume.$$\n\+$$Issue.$$\n\+$$Year.$$\n\+$$ISO.$$\n\+$$ArticleTitle\_.\{-}ArticleTitle$$\n\+$$MedlinePgn.$$\n\+$$FirstAuthor.$$$/\1\r\6\r\5\r\4\r\2\r\3\r\7\r\8/ :help regexp :help substitute (and several links therein such as \|pattern\| and \|sub-replace-special\|) Regards, Chip Campbell ### garbage notes in vim.sf.net's tips section Hello, Scott! I mentioned how there were lots of garbage notes that have been appended to nearly all tips; as an example, I gave out tip#1. I see that the garbage has been cleaned from tip#1, but tips #12-1393 also need cleaning. Seems like it needs some automation to do it, especially if the #() who obviously used a program/script to do it the first time repeats his/her vandalism. Regards, Chip Campbell ### Re: Find and replace in visual area. Silva, Paulo wrote: Nope, that didn't helped much. But no worries, the simple replace when visual is still selected works fine. I gess I'll never know why, but then again it dosen't matter really if I can do it some other way. In that case, you may wish to consider vis.vim -- it allows you to perform command mode operations on a visual block/character/line selected region, including substitutes: ctrl-v move :B s/abc/def/g as an example. You can get the latest vis.vim from http://mysite.verizon.net/astronaut/vim/index.html#VIS or a more stable version from: http://vim.sourceforge.net/scripts/script.php?script_id=1195 Regards, Chip Campbell ### Re: Reformat in visual area - vmap question John Cordes wrote: I have very little experience writing 'map' commands for my .vimrc (Linux). For some years I've had the following two commands for reformatting with the par utility. reformat paragraph with no arguments: map ** {!}par^M} reformat paragraph with arguments: map ^V {!}par They both work well, but I frequently would like to run par on a visual selection. I naively tried vmap ^V {!}par but this fails with the message (when I try * 55 on a selected area) :','!}par 55 shell returned 127 I would appreciate a suggestion here. Well, I don't appear to have par on my FC5 box; so my suggestion will have been untested. However, here it is anyway: 1. Get vis.vim from: http://mysite.verizon.net/astronaut/vim/index.html#VIS or a more stable version from: http://vim.sourceforge.net/scripts/script.php?script_id=1195 2. Select your block of text ctrl-v move :B !par The vis.vim plugin provides the :B command, which allows visual blocks/character/line selected regions to be handled by ex-mode commands (such as :!par). Regards, Chip Campbell ### Re: Reformat in visual area - vmap question John Cordes wrote: On [2007-01-09 at 10:50am] Charles E Campbell Jr [EMAIL PROTECTED] wrote: John Cordes wrote: They both work well, but I frequently would like to run par on a visual selection. I naively tried vmap ^V {!}par but this fails with the message (when I try 55 on a selected area) :','!}par 55 shell returned 127 1. Get vis.vim from: 2. Select your block of text ctrl-v move :B !par The vis.vim plugin provides the :B command, which allows visual blocks/character/line selected regions to be handled by ex-mode commands (such as :!par). Thanks for the response. I usually would be using Shift-V to select the lines for formatting; I take it vis.vim wouldn't work in that case? The example given above was for visual-block; Shift-V is visual line selection. All three visual selection methods: by block (ctrl-v), by character (v), and by line (V), are supported. Regards, Chip Campbell ### Re: Reformat in visual area - vmap question Tim Chase wrote: Thanks for the response. I usually would be using Shift-V to select the lines for formatting; I take it vis.vim wouldn't work in that case? Heh, Dr. Chip answered the other half of my response. :) Normal ranges operate linewise. Dr. Chip's vis.vim plugin overcomes this limitation, and allows ranges to be treated block-wise and character-wise. So if you only need linewise, vim already does it. If you need to overcome that limitation, use vis.vim. :) Yep, vim already supports linewise, but I figured I'd include it in vis.vim for completeness (and for those whose fingers get into a pattern!). It only cost two extra lines of script (one to test if its 'V' mode, the other to pass it along to vim: ',' [command] ). Chip Campbell ### Re: Find and replace in visual area. Silva, Paulo wrote: Greetings, I'm trying to do a replace in a selection. After selecting the area, with v, directional keys, v again (or not - both give the same result). Then I type :%s/\%V20/21/ and I get: E71: Invalid character after \% This works the same with any caracter that I put after the \% even with no character. Am I doing something wrong? I don't know why you're having problems with \%anything ; it sounds (ie. settings in your .vimrc): completion (:echo cpt), magic (:echo magic), cpoptions (:echo cpo-- is l in it?), compatible (:echo cp), etc. Regards, Chip Campbell ### Re: % jumping over {} in c-files in the midst of {{{ folds Suresh Govindachar wrote: (snip) Enter following text: if(1) { /* --- {{{3 */ } Now try to jump between { using %. Bug: The { in the manual fold-markers interferes with %-jumping. [comments on using the matchit plugin] % is a feature of Vim -- I am not trying to use % in any fancy way, only in the way it is supposed to work under regular Vim. I am reporting a bug in vim (and not looking for a work-around based on a plugin). The bug is that % is not ignoring { within c-comments in a c-file. Jürgen Krämer wrote: (snip) what did lead you to the conclusion that the behaviour of % -- to not ignore matching parentheses inside comments -- is a bug? In my past experience, % always ignored { inside c-comments for c-files (turns out my cpoptions does not include %). I don't see a place in the help files where % is documented to skip comments. You can only force it to skip strings by removing % from cpoptions (see :help cpo-%). Suresh Govindachar wrote: In the steps I gave to reproduce the bug, adding the following: :set cpo-=% does not make %-jumping skip the { inside comments. So it is a bug in Vim. Jürgen Krämer wrote: IMHO ignoring comments while searching for a matching parenthesis might be considered a missing feature, but this can easily -- as Tony wrote -- be implemented by sourcing the matchit plugin. Suresh Govindachar wrote: After adding :set cpo-=% to the steps given in OP to reproduce the bug, one sees that there is a bug in Vim. - Its not a bug. Vi compatible behavior governs this, with one exception: if a % is missing from cpoptions, the %-brace matching will skip the innards of strings. Vim's documentation doesn't state anything about skipping braces/parentheses inside of comments. As Jürgen said, it may be nice to ask for a new feature supporting the skipping of braces inside comments, especially in light of the default folding pattern. However, the documentation doesn't claim that % will skip over comments but rather that vi-compatible behavior will occur, hence the behavior is not a bug. Perhaps you should ask Bram for a '{' option in cpoptions to support this idea for a new feature. C Campbell ### Re: How to open multiple files in split windows? Peng Yu wrote: gvim a b The above command will open a and b. But only one file will be show at one time. How to show them in to split windows? Tim already showed how to open the two files in split windows by modifying the command above. However, if one has already typed gvim a b and then wants them all in separate split windows: :sba will do the trick. This produces horizontally split windows. If you want vertically split ones: :vert sba is what you want. Regards, Chip Campbell ### tip comment pollution Hello! Looks like the spammers have been adding their pollution to the tips. Our (unfortunately) hardworking tip inspectors have been getting rid of new spamtips, but the spammers have now started using the Additional Notes process. I note that many of my own tips seem to have four or more pieces of garbage appended. As an example, consider tip#1: http://vim.sourceforge.net/tips/tip.php?tip_id=1 . Can our tip inspectors also elide this form of pollution? Regards, Chip Campbell ### Re: Questions about syntax highlight script. [EMAIL PROTECTED] wrote: Hi vimmers, I've got some question when writing my syntax highlight script. Q1. The language requires a ^M character as a keyword. The ^M character is by default highlighted but I want to highlight it to some other color, at least it should be different from ^L and ^N... It seems impossible to match the ^M by :syn match Testgroup ^M (Note the ^M is obtained by press C-K, release, then press C-M, release, then press Enter) and does not highlight it as desired. It seems always highlighted to some other color. Looks like you've got a problem; the SpecialKey highlighting (see :he hl-SpecialKey) currently can't be overridden with syntax highlighting. It does appear that the :match (and friends :2match and :3match) can override the SpecialKey highlighting for a specific control character. This problem is mentioned in :help todo , line#1482 (using vim 7.0's help). As an example for how to use :3match: :3match Testgroup /\%x0d/ Q2. The string for the script language can be as long as 50-100 lines, when I write a :syn region for string, it works but sometimes when I go page down and page up, the lines of the string are highlighted as Normal instead of String, seems that the context are not concerned. Any work around? :help syn-sync Q3. The first occurence of colon and the following occurences in a line have different meanings. So, if there are text: :::; I want to highlight the first colon as GroupA, and highlight all following occurences of colon in the same line as GroupB. Is that possible? Sure! Here's an example summarizing the above: syn clear syn sync fromstart syn region Colons matchgroup=FirstColon start=':' end='\$' contains=MoreColons syn match MoreColons ':' contained	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.4563305675983429, "perplexity": 8644.048184842266}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-27/segments/1656104215805.66/warc/CC-MAIN-20220703073750-20220703103750-00526.warc.gz"}
https://www.ias.ac.in/listing/bibliography/boms/K_Byrappa	• K Byrappa Articles written in Bulletin of Materials Science • Ionic conductivity and hopping rate data for some NASICON analogues The a.c. conductivity of ionic materials shows two regions of frequency-dependent conductivity over a wide range of frequencies. Jonscher’s law of dielectric response for ionic conductors enables us to characterize the conductivities. The region of low frequency dispersion approximates to a frequency-independent plateau enabling us to obtain the d.c. conductivity. In some other conductors, the presence of low-frequency dispersion cannot be neglected while determining the effective d.c. conductivity. We have used this method to extract the d.c. conductivity and hopping rate as well as to estimate concentrations of the mobile ions (carriers) in some NASICON analogues. • Conductivity pre-exponential factors for some new superionic conductors The pre-exponential factors obtained from the ionic conductivity studies on Na2(La, Al)ZrP3O12, Na2(La, Al)TiP3O12, NH4Zr2V3O12 and AlPO4:Li+ have been analysed. The compensation law has been found to be valid for these materials indicating that the entropy is directly related to the activation energy. The 1/α vsβ plots show straight lines for most of the superionic materials except for a few and this variation has been discussed. • NH4Zr2V3O12 proton conductor NH4Zr2V3O12, a new proton conductor, has been synthesized by flux, melt and hydrothermal methods. The crystals were subjected to X-ray diffraction, differential thermal analysis, infrared spectroscopy and impedance measurements. • X-ray structure, hydrogen bonding and lattice energy analysis of (2$E$)-1-(anthracen-9-yl)-3-(4-substitutedphenyl)prop-2-en-1-ones (2$E$)-1-(anthracen-9-yl)-3-(4-chlorophenyl)prop-2-en-1-ones and (2$E$)-1-(anthracen-9-yl)-3-(4-nitrophenyl) prop-2-en-1-ones crystallize in the monoclinic crystal system with space group P2$_1$/c. Single-crystal X-ray diffraction data for both the compounds were collected on an X’Calibur CCD area detector diffractometer (Oxford Diffraction)using Mo$K\alpha$ radiation ($\lambda = 0.7107$ $\AA$) at 293(2) K. The crystal structures were solved by direct methods and refined by full-matrix least-square procedures to a final $R$ value of 0.0468 [I] and 0.0486 [II]. The crystal structures as elucidated by X-ray diffraction methods show the presence of a few intermolecular interactions, and the nature and energetics associated with these interactions have been characterized using PIXEL software. • # Bulletin of Materials Science Volume 43, 2020 All articles Continuous Article Publishing mode • # Editorial Note on Continuous Article Publication Posted on July 25, 2019	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6252166032791138, "perplexity": 3738.7132218562633}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-10/segments/1581875145648.56/warc/CC-MAIN-20200222023815-20200222053815-00517.warc.gz"}
https://minhvietacademy.org/3qx4l/9s6y.php?dx=ioslides-table	# Ioslides Table Hooks for customizing HTML and PDF output (include CSS, headers, and footers). There is also a module with filters (e. The rmarkdown package contains the following man pages: all_output_formats beamer_presentation compile_notebook convert_ipynb default_output_format draft find_external_resources github_document html-dependencies html_document html_document_base html_fragment html_notebook html_notebook_metadata html_notebook_output html_vignette includes ioslides_presentation knit_params_ask knitr_options. In some cases, you might want to make manual adjustments to your PowerPoint presentation after you render it. All settings shown below except for out. Someho9w, this changed, not the TOC has the main title of the full presentation with slide numbers (in parenthese. R Markdown has built in support for HTML, PDF, MS_Word, ODT, RTF, Markdown, and Github flavored Markdown. To create a Slidy presentation from R Markdown, you specify the slidy_presentation output format in the YAML metadata of your document. com 38 votes How to make second level indented bullet points using RMarkdown ioslides?. toc Add a table of contents at start of document X X X X X X X toc_depth The lowest level of headings to add to table of contents X X X X X X toc_float Float the table of contents to the le" of the main content X html pdf d odt rtf md gituhb ioslides slidy amer Table Suggestions Citations and Bibliographies Several functions format R data into. Flegal" output: ioslides_presentation: smaller: yes --- ## Introduction - Permutation tests, also called randomization tests, re-randomization tests, or exact tests - Type of statistical significance test in which the distribution of the test statistic under the null hypothesis is obtained by calculating all possible values of the test statistic. titles, labels, fonts, background, gridlines, and legends. Convert R Markdown documents into a variety of formats. 14) Support for opts_template in knitr options. Create Awesome HTML Table with knitr::kable and kableExtra Hao Zhu 2019-05-03. Or copy & paste this link into an email or IM:. R Markdown has built in support for HTML, PDF, MS_Word, ODT, RTF, Markdown, and Github flavored Markdown. Here's how. 2 Slidy presentation. You can create a slide show broken up into sections by using the ## heading tag (you can also create a new slide without a header using a horizontal rule (---). The first official book authored by the core R Markdown developers that provides a comprehensive and accurate reference to the R Markdown ecosystem. Aha, here's why list numbering doesn't work as you expected in an ioslides_presentation: Regular HTML documents are rendered from markdown into HTML by pandoc, using its fancy_lists extension that makes it sensitive to the type of marker you use in your markdown. The remark. I'm looking for the best Rmd presentation package to introduce to beginners. You’ll build on simple programming. Karl Broman introduces: kable, pander, and xtable and many useRs like the first two:. , bold) row labels, and pander provides no option to change this behavior. sub-option description html pdf word odt rtf md github ioslides slidy beamer; citation_package: The LaTeX package to process citations, natbib, biblatex or none. 1) was using DataTables v1. From the window's sidebar, select the category of output that you plan to convert your. If you want to make a somewhat nicer table, the simplest approach is to use the kable function in the knitr package. Active 10 months ago. table() in a ioslides slide and I can't figure out how to get rid of the NULL caption at the bottom of the table. Communicate your results with others. Table Header \| Second Header Syntax Becomes R Markdown Reference Guide Syntax for slide formats (ioslides, slidy, beamer) ioslides f w o h p. 14) Support for opts_template in knitr options. Importing data and more basics' author: "Prof. table or change the default style using panderOptions. TOC for IOslides in Rmarkdown. tabset-fade. To produce a code block in Markdown, simply indent every line of the block by at least 4 spaces or 1 tab. For example, 8-outputs. To open a new file, click File > New File > R Markdown in the RStudio menu bar. \item A dollar sign is \$, an ampersand \&, and a \textbackslash{}. The default slide transition ("linear") is a simple right-to-left animation. BUFFALO NICKEL FIVE CENT. Formatted tables with knitr::kable() The function kable() from the knitr package produces pretty, formatted tables produced by R code (rather than the default R output style). Advanced Layout. A window will pop up that helps you build the YAML frontmatter for the. Currently kableExtra 0. ioslides, Beamer Microsoft. He then shows how to include R code in your documents and add visual interest with slides, charts, images, and tables. Bootstrap table classes. ly/RUGgre18. © 2017 RStudio Inc. Rmd file into. R Markdownを使うときれいなレポートの生成の自動化がやりやすいですが、よりステキな見た目にするために色々工夫ができそうです。いくつか試した内容を備忘録としてまとめておきます。 ※ここで記載しているのはいずれ. mpg cyl disp hp drat wt qsec vs am gear carb; Mazda RX4: 21. Create HTML, PDF, and MS Word documents as well as Beamer and ioslides presentations New markdown syntax including expanded support for tables, definition lists, and bibliographies A responsive (multi-device friendly) and themeable HTML template based on Bootstrap. toc Add a table of contents at start of document X X X X X X X toc_depth The lowest level of headings to add to table of contents X X X X X X toc_float Float the table of contents to the le" of the main content X html pdf d odt rtf md gituhb ioslides slidy amer Table Suggestions Citations and Bibliographies Several functions format R data into. 0' jupytext_formats: ipynb,Rmd:rmarkdown,R kernelspec: display_name: R language: R name: ir language_info: codemirror_mode: r. Pandoc markdown supports several syntaxes for defining tables which are described in the pandoc online documentation. I get the tables correctly, however simple formatting from the vignette examples seems to be gone. The default slide transition ("linear") is a simple right-to-left animation. I am using kableExtra on a ioslides_presentation R markdown file. 值得学习的R Markdown 包： xtable, stargazer, pander, tables, and ascii packages. This page is dedicated to R for Everyone: Advanced Analytics and Graphics, my book from Addison Wesley, now in its Second Edition. I first used it to create a simple presentation on Life as a Contractor which took about an hour to create after looking at a short tutorial with ioslides and html versions. I put together a short intro presentation for some people explaining a little bit about R from an introductory point of view. --- title: 'Bootstrap' author: "James M. You can create many types of output from a single. The RStudio IDE provides a template document when you open a new. Create Awesome HTML Table with knitr::kable and kableExtra Hao Zhu 2019-05-03. --- title: "Grammar of Graphics and ggplot2" author: "Timothy Thornton (tathornt@uw. toc Add a table of contents at start of document X X X X X X X toc_depth The lowest level of headings to add to table of contents X X X X X X toc_float Float the table of contents to the le" of the main content X html pdf d odt rtf md gituhb ioslides slidy amer Table Suggestions Citations and Bibliographies Several functions format R data into. The first official book authored by the core R Markdown developers that provides a comprehensive and accurate reference to the R Markdown ecosystem. Formatted tables with knitr::kable() The function kable() from the knitr package produces pretty, formatted tables produced by R code (rather than the default R output style). I've made a basic shiny app using ScatterD3 here, but when I try to embed it in an ioslides presentation it gets cut off and a scrollbar appears. I have several shiny ioslides presentations copied on my home and work machines. r documentation: Adding a footer to an ioslides presentation. However, the built-in ones (that come with RStudio/the rmarkdown package) rely on Bootstrap and also use jQuery. 0; Functions to test R functions. Table Header \| Second Header Syntax Becomes R Markdown Reference Guide Syntax for slide formats (ioslides, slidy, beamer) ioslides f w o h p. Alignments can be specified as with pipe tables, by putting colons at the boundaries of the separator line after the. On each machine:. Aha, here's why list numbering doesn't work as you expected in an ioslides_presentation: Regular HTML documents are rendered from markdown into HTML by pandoc, using its fancy_lists extension that makes it sensitive to the type of marker you use in your markdown. Use a productive notebook interface to weave together narrative text and code to produce elegantly formatted output. The easiest way to create a slideshow is to write a simple markdown file, like habits. Formatted tables with knitr::kable() The function kable() from the knitr package produces pretty, formatted tables produced by R code (rather than the default R output style). Noob Question: Can you change the color of the text in a markdown block? Showing 1-7 of 7 messages. Pandoc markdown supports several syntaxes for defining tables which are described in the pandoc online documentation. And, the main reason for me to choose ioslides rather than Slidy is simple. En particular, es muy común tener que colaborar con personas que se sienten mucho más cómodas trabajando con presentaciones en PowerPoint que en las creadas con beamer o ioslides. Or copy & paste this link into an email or IM:. The table or figure number can be added using inline R code just as was done in the references done above. 2017)manifesto. Hua Zhou @ UCLA" date: "Jan 31, 2019" subtitle: Biostat M280 output: # ioslides_presentation: default html. I am using kableExtra on a ioslides_presentation R markdown file. css templates. If you want to make a somewhat nicer table, the simplest approach is to use the kable function in the knitr package. In his Knitr in a Knutshell, Dr. Slides put together with R/markdown and ioslides. Create HTML, PDF, and MS Word documents as well as Beamer, ioslides, and Slidy presentations. I first used it to create a simple presentation on Life as a Contractor which took about an hour to create after looking at a short tutorial with ioslides and html versions. Table of contents in R Markdown ioslides. I've made a basic shiny app using ScatterD3 here, but when I try to embed it in an ioslides presentation it gets cut off and a scrollbar appears. Output Options. Plus, learn how to customize the styles in your document, override markdown, and insert prebuilt data visualizations with htmlwidgets. Shiny (>= v1. First of all we have to include the jQuery plugin. Markdown语法很大程度上减少了编辑的成本，但是在写作这篇文章的时候也发现某些标记对中文的支持似乎并不完美，虽然这些缺陷可以通过直接插入HTML代码解决（但这么做一点都不漂亮）。. Pandoc Markdown supports several syntaxes for defining tables, which are described in the Pandoc Manual. Estaba tratando de hacer una guía de colores circular (que los extremos tengan el mismo color) para hacer gráficos de ángulos o direcciones del viento, cuando descubrí una forma interesante de crear un efecto de relieve en mapas de topografía. TURBO Jammer Badehose Schwimmhosen Herren AUSTRALIA ROAD SIGN schwarz Känguruh,Deutz Fahr KM 3. I'm looking for the best Rmd presentation package to introduce to beginners. ioslides is also simple to use and looks better than Slidy out-of-the-box, but there are some potential compromises for this simplicity. An extension to R called R Markdown lets us mix R code, analyses, text, tables, and other formatting to make all sorts of products. Results in the following displayed in the document. May 5, 2018, 12:09am #1. Rmd file into. - When building a query, we don’t want the entire table, often we want just enough to check if our query is working. frame with two columns. sub-option description html pdf word odt rtf md github ioslides slidy beamer; citation_package: The LaTeX package to process citations, natbib, biblatex or none. The RStudio IDE provides a template document when you open a new. you may read the source code if you are interested in the implementation, and these formats primarily used a post-processor function to post-process the HTML/LaTeX output to, for example, split the HTML output into multiple pages, number figures/tables, resolve cross-references, and so on. Before writing your own Rmarkdown document, use the excellent ressource on commonmark. Pandoc markdown supports several syntaxes for defining tables which are described in the pandoc markdown specification. Aha, here's why list numbering doesn't work as you expected in an ioslides_presentation: Regular HTML documents are rendered from markdown into HTML by pandoc, using its fancy_lists extension that makes it sensitive to the type of marker you use in your markdown. This approach is known as literate programming. But note that it appears to work in HTML too. --- title: "Lecture 24: Random Simulation, For Fun And Profit" output: ioslides_presentation --- ## Previously Topics we got to earlier in the course: - How to make draws from, and use random distributions - Writing functions with known run-times and verifiable results - Why not to use for loops ## Today. Formatted tables with knitr::kable() The function kable() from the knitr package produces pretty, formatted tables produced by R code (rather than the default R output style). When using kable() as a top-level expression, you do not need to explicitly print() it due to R's automatic implicit printing. ---title: R Markdown output: html_document---This is an R Markdown document. , bold) row labels, and pander provides no option to change this behavior. As I sifted through the various pieces of software that are designed for creating presentation slides, it occurred to me: why learn yet another program, when I can instead use the tools that I'm already familiar with? With a bit of fiddling, we can easily create beautiful presentations with HTML and. IOslides using Rmarkdown does not have the ability to add a table of content page in the YAML header. R Markdown documents can be rendered to many output formats including HTML documents, PDFs, Word files, slideshows, and more, allowing you to focus on the content while R Markdown takes care of your. But with this one text file, it's easy to produce multiple output types: PDF or Word formatted documents; HTML for blogs, web sites, or even slide presentation. TOC for IOslides in Rmarkdown. exe: Cannot decode byte '\xa0': Data. A Demonstration of the ioslides Presentation Engine As Emulated by Bespoke. This is addition to the text formatting mentioned above. 6 x Christmas Joyful Snowman 3D Hanging Decorations,NWT Pottery Barn Kids DEAR SANTA TWIN FLANNEL SHEET SET HOLIDAY! LAST ONE!,Summer Flamingo Shaped LED Lights 10 light String, 3 ft. csv()等功能的平面文件。导入平面文件数据的特定 R 语言包是 data. ),1937 D Buffalo Nickel #W50. Pandoc is a universal converter 19, allowing markup languages to flop from one format to another. opened on modal) with sections for each table and with module for a single condition. I'm doing a presentation with R Markdown v2 and ioslides. You produce all the plots and tables in R and just paste them into PowerPoint, right? Or you might have gone a bit further and already used RMarkdown with ioslides, Slidy or Beamer. Allaire, Garrett Grolemund na Amazon. Workflow R Markdown is a format for writing reproducible, dynamic reports with R. Access Google Slides with a free Google account (for personal use) or G Suite account (for business use). - This adds marginal totals, they come in handy - I'm printing the raw count and percent in each cell (different from my past idea) ## Variations {r pctable2} summary(t1, rowpct = TRUE, colpct = FALSE) ## Having both is admittedly frustrating {r pctable3} summary(t1, rowpct = TRUE, colpct = TRUE) ## Features - rounded = TRUE is. Manually changing the slide size or design after rendering will automatically change these elements to match the new style. 변환 가능한 저작물로는 notebook, html, pdf, word, odt등의 문서와 ioslides, reveal. width and out. This document provides a workaround to automaticly add a TOC. 第一个工具是R Markdown，采用knitr和pandoc复制方式生成您的数据分析结果报告。使用R markdown工具，R语言最终生成文档，替换R语言代码。文档可以是html、word、pfd、ioslides等格式。您可以通过本教程学到更多知识并使用cheatsheet作为参考资料。. Date()' output: ioslides_presentation: default beamer. IOslides using Rmarkdown does not have the ability to add a table of content page in the YAML header. The function coord_polar() is used to produce a pie chart, which is just a stacked bar chart in polar coordinates. From the window’s sidebar, select the category of output that you plan to convert your. This will not center the caption. # ' The ioslides template has an attractive default style for tables so you # ' shouldn't hesitate to add tables for presenting more complex sets of # ' information. The kable function is part of the knitr package and can be extended using the kableExtra package. The RStudio IDE provides a template document when you open a new. table and dplyr to be used together. The HTML tag is used for indicating a piece of code. Today with RMarkdown in RStudio, it is easy to turn your analysis into a presentation. ioslides provides presenter notes that cannot be easily added with any other presentation type. If you want to make a somewhat nicer table, the simplest approach is to use the kable function in the knitr package. This R tutorial describes how to create a pie chart for data visualization using R software and ggplot2 package. The knitr/R markdown system is a great way to organize reports and analyses. Don't implicitly discover directories when scanning for dependent resources. = Una graﬁca: = 3. # R Markdown. 16 Maintainer Yihui Xie Description Convert R Markdown documents into a variety of formats. One of the neat tools available via a variety of packages in R is the creation of beautiful tables using data frames stored in R. table, pero entiendo que no sea para todos. --- title: "Introduction to Classification" output: ioslides_presentation: smaller: true --- {r setup, include=FALSE} knitr::opts_chunk$set(echo = TRUE. Turn your analyses into high quality documents, reports, presentations and dashboards with R Markdown. Markdown is a simple formatting syntax for authoring HTML, PDF, and MS Word documents. kable_styling offers a few other ways to customize the look of a HTML table. (@) Think what is 0. Please see the package documentation site for how to use this package in LaTeX. frame, a matrix, or a table and is the first argument to kable(). 1 1 There is also a slidedeck that goes along with this handout available here, which is worth looking at if you don't know what you're doing on this page and what to look at. Slidy, ioslides, and Beamer are different technologies for creating HTML presentations with R Markdown. 1) was using DataTables v1. En particular, es muy común tener que colaborar con personas que se sienten mucho más cómodas trabajando con presentaciones en PowerPoint que en las creadas con beamer o ioslides. The RStudio IDE provides a template document when you open a new. Wanyi Zhang's Data Projects. Fix for slide numbers not showing up in ioslides when served from the filesystem (don't call pushState for file:// urls). With this example code: {r, results='asis',. I'm using render to create an ioslides presentation with a table generated from pandoc. titles, labels, fonts, background, gridlines, and legends. Create HTML, PDF, and MS Word documents as well as Beamer, ioslides, and Slidy presentations. Slide Transitions and Navigation in R Presentations Transitions. これはR Markdown Tablesで説明しますので、本項ではテキストベースの表のみ説明となります。テキストベースの表は以下のように記述します。表の幅は文字数により出力フォーマットの幅に収まるように調整されます。. Here is an example to illustrate the default behavior. Let us know how converting your presentations from Google Slides to PowerPoint or other formats works for you. When you want to #' help the audience focus exclusively on the highlighted region press the #' \code{'h'} key and the rest of the code will fade away. \| All Rights Reserved \| Terms Of Use. But in San Diego, Yihui said that they are close to adding PowerPoint as an output format. Charts and data automatically update inside your slide deck when you re-save the chart in Python, R, or Chart Studio. Noob Question: Can you change the color of the text in a markdown block? Showing 1-7 of 7 messages. I have several shiny ioslides presentations copied on my home and work machines. R Markdown documents can be rendered to many output formats including HTML documents, PDFs, Word files, slideshows, and more, allowing you to focus on the content while R Markdown takes care of your. Here is an example to illustrate the default behavior. It looks like a data. An Example R Markdown Document (A Subtitle Would Go Here if This Were a Class) StevenV. Support for table of contents in word_document (requires pandoc >= 1. opened on modal) with sections for each table and with module for a single condition. Miller Department of Political Science. Or copy & paste this link into an email or IM:. Put bluntly, ioslides does more of the styling work for you at the cost of compatibility issues. {r} #Get the path to the data file. For example: --- title: "Never put off 'till tomorrow?". This creates a default template for making an ioslides presentation. ) However, I don't tend to hear much about R Presentations - R's answer to Powerpoint. The ioslides template has an attractive default style for tables so you shouldn’t hesitate to add tables for presenting more complex sets of information. But its table-writing functions have at least one problem: they automatically emphasize (i. 8-4 Date 2019-04-08 Title Export Tables to LaTeX or HTML Maintainer David Scott. filepath - system. 0' jupytext_formats: ipynb,Rmd:rmarkdown,R kernelspec: display_name: R language: R name: ir language_info: codemirror_mode: r. The HTML tag is used for indicating a piece of code. He then shows how to include R code in your documents and add visual interest with slides, charts, images, and tables. Alignments can be specified as with pipe tables, by putting colons at the boundaries of the separator line after the. If you have used DataTables in Shiny before (specifically, before Shiny v0. Let's take a quick look at the YAML. When using kable() as a top-level expression, you do not need to explicitly print() it due to R's automatic implicit printing. Why I use R for Data Science - An Ode to R ioslides or reveal. Output Options. 0: 6: 160: 110: 3. Please see the package documentation site for how to use this package in LaTeX. Support for table of contents in word_document (requires pandoc >= 1. 1Introduction This document gives a gallery of tables which can be made using the xtable package to create LATEX output. { "cells": [ { "cell_type": "raw", "metadata": {}, "source": [ "--- ", "title: \"Web scraping with Python Exercises\" ", "output: ioslides_presentation. Shiny (>= v1. This creates a default template for making an ioslides presentation. A floating table of contents for easy navigation between sections is provided by default. 50 Updated: 8/14 1. ## Pandoc extension: examples We have some examples. js, Slidy, Beamer의 슬라이드, 대쉬보드, 웹페이지, 책 등 입니다. The new flexbox layout mode is poised to redefine how we do layouts in CSS. From the window’s sidebar, select the category of output that you plan to convert your. To promote my “pander” package a bit: you can easily turn (almost) any R object into markdown with a general S3 method. And for informal reports, I'll often just print out a matrix or data frame, rather than create a formal table. 46: 0: 1: 4: 4: Mazda RX4 Wag: 21. R Markdown: The Definitive Guide is the first official book authored by the core R Markdown developers that provides a comprehensive and accurate reference to the R Markdown ecosystem. html file which can be opened in browser and can insert interactive graphs in it. # R Markdown. Users are advised to stick with the default multiline style, but if there is a need to change it either specify style argument when calling pander/pandoc. Flat files：您可以从预先安装的 utils 包导入带有 read. Image Caption. Someho9w, this changed, not the TOC has the main title of the full presentation with slide numbers (in parenthese. Cells that span multiple columns or rows are not supported. In what follows, I'll discuss these different options using data on departing flights from Seattle and Portland in 2014. filepath - system. Just after \begin{array} the format of each column should be listed, use c for a center aligned column, r for right aligned, l for left aligned and a \| for a vertical line. I kept wondering who to plot two R plots side by side (ie. Advanced Layout. You can also create tables, graphs, and more. There are options to control the number of digits, whether row names are included or not, column alignment, and other. R Markdown files are just text files. Let's create a new R Markdown file, but this time instead of creating a document we're going to do a presentation. Multinational clinical trial: region/country/site ## Problems with PDF Model - Exquisite control of formatting; beautiful printing - Only Adobe Acrobat Reader supports javascript in pdf files, for pop-ups etc. Rmd file into. El paquete dtplyr permite usar los verbos de dplyr para manipular data. {r setup, include. The rmarkdown package can create web pages, PDFs, and slide presentations from R Markdown documents. Rmd Word Un informe Una figura: {r} hist(co2) Un informe: Un informe. Help with Rmd and ioslides and css. --body is a string, metadata is a table, variables is a table. He then shows how to include R code in your documents and add visual interest with slides, charts, images, and tables. titles, labels, fonts, background, gridlines, and legends. 值得学习的R Markdown 包： xtable, stargazer, pander, tables, and ascii packages. TOC for IOslides in Rmarkdown. 第一个工具是R Markdown，采用knitr和pandoc复制方式生成您的数据分析结果报告。使用R markdown工具，R语言最终生成文档，替换R语言代码。文档可以是html、word、pfd、ioslides等格式。您可以通过本教程学到更多知识并使用cheatsheet作为参考资料。. R Markdown: The Definitive Guide is the first official book authored by the core R Markdown developers that provides a comprehensive and accurate reference to the R Markdown ecosystem. I haven't been able to find anything online that addresses my specific question. Pandoc markdown supports several syntaxes for defining tables which are described in the pandoc online documentation. --- title: "Data Transformation With dplyr" author: "Dr. R Markdown Cheat Sheet learn more at rmarkdown. Importing data and more basics' author: "Prof. In his Knitr in a Knutshell, Dr. Plus, learn how to customize the styles in your document, override markdown, and insert prebuilt data visualizations with htmlwidgets. 2) currently uses DataTables v1. js guide, e. Tibble prints the data. Someho9w, this changed, not the TOC has the main title of the full presentation with slide numbers (in parenthese. # ' The ioslides template has an attractive default style for tables so you # ' shouldn't hesitate to add tables for presenting more complex sets of # ' information. Free W3 CSS Themes and Templates. # Use custom color palettes pie + scale_fill_manual(values=c("#999999. You get less visual control than with a tool like Keynote or PowerPoint, but automatically inserting the results of your R code into a presentation can save a huge amount of time. 400+ pages of professional hints and tricks. Yo soy un declarado fan de la sintaxis de data. table or change the default style using panderOptions. This page is dedicated to R for Everyone: Advanced Analytics and Graphics, my book from Addison Wesley, now in its Second Edition. Or copy & paste this link into an email or IM:. Further work is anticipated on the following:. Essentially a babel fish for web, it reads the markdown, HTML, $$\LaTeX$$, and everything else and converts it to an HTML, pdf etc. 14) Support for opts_template in knitr options. The default slide transition ("linear") is a simple right-to-left animation. Each output format is implemented as a function in R. To produce a code block in Markdown, simply indent every line of the block by at least 4 spaces or 1 tab. 0: 6: 160: 110: 3. Adding captions to images Two new elements are the HTML5 tags FIGURE and FIGCAPTION. Hundreds of free powerpoint templates updated weekly. The first one, FIGURE, is good for things like images and other graphics, while FIGCAPTION is used to tell people what they are looking at. The knitr package includes a function called kable that makes basic knitr tables. opened on modal) with sections for each table and with module for a single condition. The RStudio IDE provides a template document when you open a new. Table des matières À propos 1 Chapitre 1: Premiers pas avec le langage R 2 Remarques 2 Modification de R Docs sur le dépassement de pile 2 Quelques caractéristiques de R que les immigrants d'autres langues peuvent trouver inhabit 2. Use a productive notebook interface to weave together narrative text and code to produce elegantly formatted output. 46: 0: 1: 4: 4: Mazda RX4 Wag: 21. Further work is anticipated on the following:. Pandoc markdown supports several syntaxes for defining tables which are described in the pandoc online documentation. You can create many types of output from a single. Allaire, Garrett Grolemund na Amazon. 1) was using DataTables v1. table() in a ioslides slide and I can't figure out how to get rid of the NULL caption at the bottom of the table. So let's type in the title for this like Module 2- ioslides and click OK. js guide, e. This is done by the line. But note that it appears to work in HTML too. Turn your analyses into high quality documents, reports, presentations and dashboards with R Markdown. Markdown语法很大程度上减少了编辑的成本，但是在写作这篇文章的时候也发现某些标记对中文的支持似乎并不完美，虽然这些缺陷可以通过直接插入HTML代码解决（但这么做一点都不漂亮）。. table() 和 read. ly/RUGgre18`. Posted on March 5, 2016 by steve in R Markdown What my CV looks like with this template. Estaba tratando de hacer una guía de colores circular (que los extremos tengan el mismo color) para hacer gráficos de ángulos o direcciones del viento, cuando descubrí una forma interesante de crear un efecto de relieve en mapas de topografía. And for informal reports, I’ll often just print out a matrix or data frame, rather than create a formal table. Themes can be used to give plots a consistent customized look. The cells of grid tables may contain arbitrary block elements (multiple paragraphs, code blocks, lists, etc. tab" , package="datasets") file. Here is an example to illustrate the default behavior. ) However, I don't tend to hear much about R Presentations - R's answer to Powerpoint. This is identifying information used when selecting which jobs to display. --body is a string, metadata is a table, variables is a table. Rmarkdown ioslides allowframebreaks alternative; include blockquote in rmarkdown ioslides; Rmarkdown ioslides changing table headers; RMarkdown ioslides presentation in HD; Rmarkdown : embed html file to ioslides; RMarkdown tikz engine in ioslides presentation; Printing Rmarkdown ioslides presentation with notes included. Ioslides is a nice R presentation format characterized by the simplicity of the result.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.22740128636360168, "perplexity": 8647.250421474339}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-47/segments/1573496670268.0/warc/CC-MAIN-20191119222644-20191120010644-00012.warc.gz"}
http://travelprnews.com/air-france-announces-summer-2017-schedule-748575767/travel-press-release/2017/01/26/	# Air France announces summer 2017 schedule PARIS, 2017-Jan-26 — /Travel PR News/ — As from 18 July 2017, Air France customers will be able to travel to Agadir (Morocco) and Palma de Mallorca (Spain) on departure from Paris-Charles de Gaulle with 3 weekly flights operated on Tuesdays, Thursdays and Saturdays. The flights will be operated by Airbus A319 and A320s. From 22 July to 9 September 2017, the Company’s customers will benefit from the new direct service connecting Nice to Tel Aviv (Israel) by Airbus A320. From 24 July to 3 September 2017, Air France will operate 5 new services on departure from French regional airports. The Company’s customers will thus be able to travel to Athens (Greece) on departure from Nice and Toulouse, Malta on departure from Toulouse as well as Frankfurt (Germany) and Copenhagen (Denmark) on departure from Bordeaux by Airbus A319 and A320. A REINFORCED MEDIUM-HAUL NETWORK These new medium-haul destinations respond to leisure travellers’ high demand during the summer holiday period. Moreover, the fewer trips made by business travellers in July and August will enable the company to redeploy its aircraft on departure from the French regions. In this way, Air France is optimizing the use of its fleet and increasing capacity on its medium-haul network. These new summer services are in addition to the launch of new routes from Paris-Charles de Gaulle to Porto and Marrakech starting from the 2017 summer season (26 March 2017). TWO NEW DESTINATIONS ON DEPARTURE FROM PARIS-CHARLES DE GAULLE FLIGHT SCHEDULES (IN LOCAL TIME): Paris-Charles de Gaulle – Agadir AF1660: leaves Paris-Charles de Gaulle at 14:00, arrives in Agadir at 16:35, on Tuesdays, Thursdays and Saturdays; AF1661: leaves Agadir at 17:35, arrives at Paris-Charles de Gaulle at 22:20, on Tuesdays, Thursdays and Saturdays. Paris-Charles de Gaulle – Palma de Mallorca AF1658: leaves Paris-Charles de Gaulle at 10:40, arrives in Palma de Mallorca at 12:30, on Tuesdays and Thursdays; AF1658: leaves Paris-Charles de Gaulle at 15:45, arrives in Palma de Mallorca at 17:35, on Saturdays; AF1659: leaves Palma de Mallorca at 13:20, arrives at Paris-Charles de Gaulle at 15:25, on Tuesdays and Thursdays; AF1659: leaves Palma de Mallorca at 18:25, arrives at Paris-Charles de Gaulle at 20:30, on Saturdays. SIX NEW NON-STOP ROUTES ON DEPARTURE FROM NICE, TOULOUSE AND BORDEAUX FLIGHT SCHEDULES (IN LOCAL TIME): Nice – Tel Aviv AF1794: leaves Nice at 11:15, arrives in Tel Aviv at 16:05, on Saturdays from 22/07/17 to 09/09/17; AF1794: leaves Nice at 07:20, arrives in Tel Aviv at 12:10, on Mondays from 24/07/17 to 28/08/17; AF1794: leaves Nice at 07:15, arrives in Tel Aviv at 12:05, on Wednesdays from 26/07/17 to 30/08/17; AF1794: leaves Nice at 07:10, arrives in Tel Aviv at 12:00, on Fridays from 28/07/17 to 01/09/17. AF1795: leaves Tel Aviv at 17:15, arrives in Nice at 20:35, on Saturdays from 22/07/17 to 09/09/17; AF1795: leaves Tel Aviv at 13:20, arrives in Nice at 16:40, on Mondays from 24/07/17 to 28/08/17; AF1795: leaves Tel Aviv at 13:15, arrives in Nice at 16:35, on Wednesdays from 26/07/17 to 30/08/17; AF1795: leaves Tel Aviv at 13:10, arrives in Nice at 16:30, on Fridays from 28/07/17 to 01/09/17. Nice – Athens AF1708: leaves Nice at 8:40, arrives in Athens at 12:05, on Tuesdays from 25/07/17 to 29/08/17; AF1708: leaves Nice at 8:15, arrives in Athens at 11:40, on Thursdays from 27/07/17 to 31/08/17. AF1709: leaves Athens at 12:55, arrives in Nice at 14:40, on Tuesdays from 25/07/17 to 29/08/17; AF1709: leaves Athens at 12:30, arrives in Nice at 14:15, on Thursdays from 27/07/17 to 31/08/17. Toulouse – Athens AF1864: leaves Toulouse at 9:55, arrives in Athens at 14:00, on Mondays 24/07/17 and 28/08/17; AF1864: leaves Toulouse at 11:30, arrives in Athens at 15:35, on Mondays from 31/07/17 to 21/08/17; AF1864: leaves Toulouse at 9:30, arrives in Athens at 13:35, on Wednesdays 26/07/17 and 30/08/17; AF1864: leaves Toulouse at 15:00, arrives in Athens at 19:05, on Wednesdays and Fridays from 02/08/17 to 25/08/17; AF1864: leaves Toulouse at 10:05, arrives in Athens at 14:10, on Fridays from 28/07/17 to 01/09/17; AF1864: leaves Toulouse at 14:40, arrives in Athens at 18:45, on Saturdays from 29/07/17 to 02/09/17. AF1865: leaves Athens at 14:50, arrives in Toulouse at 17:05, on Mondays 24/07/17 and 28/08/17; AF1865: leaves Athens at 16:25, arrives in Toulouse at 18:40, on Mondays from 31/07/17 to 21/08/17; AF1865: leaves Athens at 14:25, arrives in Toulouse at 16:40, on Wednesdays 26/07/17 and 30/08/17; AF1865: leaves Athens at 19:55, arrives in Toulouse at 22:10, on Wednesdays and Fridays from 02/08/17 to 25/08/17; AF1865: leaves Athens at 15:00, arrives in Toulouse at 17:15, on Fridays from 28/07/17 to 01/09/17; AF1865: leaves Athens at 19:35, arrives in Toulouse at 21:50, on Saturdays from 29/07/17 to 02/09/17. Toulouse – Malta AF1762: leaves Toulouse at 11:30, arrives in Malta at 13:45, on Tuesdays from 25/07/17 to 29/08/17; AF1762: leaves Toulouse at 08:55, arrives in Malta at 11:10, on Thursdays 27/07/17 and 31/08/17; AF1762: leaves Toulouse at 15:05, arrives in Malta at 17:20, on Thursdays from 03/08/17 to 24/08/17; AF1762: leaves Toulouse at 11:50, arrives in Malta at 14:05, on Sundays from 30/07/17 to 03/09/17. AF1763: leaves Malta at 14:30, arrives in Toulouse at 16:55, on Tuesdays from 25/07/17 to 29/08/17; AF1763: leaves Malta at 11:55, arrives in Toulouse at 14:20, on Thursdays 27/07/17 and 31/08/17; AF1763: leaves Malta at 18:05, arrives in Toulouse at 20:30, on Thursdays from 03/08/17 to 24/08/17; AF1763: leaves Malta at 14:50, arrives in Toulouse at 17:15, on Sundays from 30/07/17 to 03/09/17. Bordeaux – Frankfurt AF1760: leaves Bordeaux at 12:45, arrives in Frankfurt at 14:35, on Tuesdays and Thursdays from 25/07/17 to 31/08/17; AF1760: leaves Bordeaux at 11:30, arrives in Frankfurt at 13:20, on Saturdays from 29/07/17 to 03/09/17. AF1761: leaves Frankfurt at 15:30, arrives in Bordeaux at 17:20, on Tuesdays and Thursdays from 25/07/17 to 31/08/17; AF1761: leaves Frankfurt at 14:25, arrives in Bordeaux at 16:15, on Saturdays from 29/07/17 to 03/09/17. Bordeaux – Copenhagen AF1772: leaves Bordeaux at 11:15, arrives in Copenhagen at 13:45, on Mondays, Wednesdays, Fridays and Sundays from 24/07/17 to 03/09/17; AF1773: leaves Copenhagen at 14:40, arrives in Bordeaux at 17:10 on Mondays, Wednesdays, Fridays and Sundays from 24/07/17 to 03/09/17. Source: Air France 41 PR reads 1 PR reads today	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9885214567184448, "perplexity": 23858.108996875308}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-34/segments/1502886102663.36/warc/CC-MAIN-20170816212248-20170816232248-00119.warc.gz"}
http://hal.in2p3.fr/in2p3-00702007	# Measurement of jet fragmentation into charged particles in pp and PbPb collisions at sqrt(s[NN])= 2.76 TeV 5 CMS IPNL - Institut de Physique Nucléaire de Lyon Abstract : Jet fragmentation in pp and PbPb collisions at a centre-of-mass energy of 2.76 TeV per nucleon pair was studied using data collected with the CMS detector at the LHC. Fragmentation functions are constructed using charged-particle tracks with transverse momenta pt > 4 GeV for dijet events with a leading jet of pt > 100 GeV. The fragmentation functions in PbPb events are compared to those in pp data as a function of collision centrality, as well as dijet-pt imbalance. Special emphasis is placed on the most central PbPb events including dijets with unbalanced momentum, indicative of energy loss of the hard scattered parent partons. The fragmentation patterns for both the leading and subleading jets in PbPb collisions agree with those seen in pp data at 2.76 TeV. The results provide evidence that, despite the large parton energy loss observed in PbPb collisions, the high-pt component of the fragmentation function evaluated with respect to the reconstructed jet momentum is not strongly modified in comparison to jet fragmentation in vacuum. Document type : Journal articles Journal of High Energy Physics, Springer, 2012, 2012, pp.87. <10.1007/JHEP10(2012)087> Domain : http://hal.in2p3.fr/in2p3-00702007 Contributor : Sylvie Flores <> Submitted on : Tuesday, May 29, 2012 - 7:12:22 AM Last modification on : Wednesday, July 27, 2016 - 2:48:48 PM ### Citation S. Chatrchyan, M. Besancon, S. Choudhury, M. Dejardin, D. Denegri, et al.. Measurement of jet fragmentation into charged particles in pp and PbPb collisions at sqrt(s[NN])= 2.76 TeV. Journal of High Energy Physics, Springer, 2012, 2012, pp.87. <10.1007/JHEP10(2012)087>. <in2p3-00702007> ### Metrics Consultations de la notice	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.945586085319519, "perplexity": 5741.81638549148}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-44/segments/1476988718957.31/warc/CC-MAIN-20161020183838-00178-ip-10-171-6-4.ec2.internal.warc.gz"}
https://sbainvent.com/fluid-mechanics/reynolds-number/	# Reynolds Number Reynolds number is a dimensionless number that is a ratio of a fluid’s inertia and the viscous effects on the fluid. Equation 1 is used to describe Reynolds number. (Eq 1) $Re=\frac{ρvD}{μ}$ Re = Reynolds Number ρ = Density v = Fluid Velocity D = Pipe Diameter μ = Dynamic Viscosity ### Laminar, Translation, & Turbulent Flow One of the main uses of Reynolds number is to describe the flow of a fluid going through a pipe. Reynolds number can be used to determine whether the fluid’s flow is laminar or turbulent flow. If the Reynolds number is less than 2100 for a round pipe then the flow can be considered laminar, while if the Reynolds number is above 4000 the flow through a round pipe can be considered turbulent. Finally, if the Reynolds number is in between 2100 and 4000 then the flow is transitional, which means part of the flow is laminar while part of it is turbulent. The reason why it is important to know if a fluids flow is turbulent or laminar is because the fluid will behave differently since the particles for a laminar flow follow a stream line, while fluid particles for a turbulent flow follow their own random paths.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7967258095741272, "perplexity": 586.6908395218314}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-43/segments/1634323587659.72/warc/CC-MAIN-20211025092203-20211025122203-00336.warc.gz"}
https://trivadis.github.io/plsql-and-sql-coding-guidelines/v3.6/4-language-usage/4-control-structures/3-flow-control/g-4350/	# G-4350: Always use 1 as lower and COUNT() as upper bound when looping through a dense array. Major Reliability ## Reason Doing so will not raise a VALUE_ERROR if the array you are looping through is empty. If you want to use FIRST()..LAST() you need to check the array for emptiness beforehand to avoid the raise of VALUE_ERROR. DECLARE TYPE t_employee_type IS TABLE OF employees.employee_id%TYPE; t_employees t_employee_type := t_employee_type(); BEGIN <<process_employees>> FOR i IN t_employees.FIRST()..t_employees.LAST() LOOP sys.dbms_output.put_line(t_employees(i)); -- some processing END LOOP process_employees; END; / ## Example (better) Raise an unitialized collection error if t_employees is not initialized. DECLARE TYPE t_employee_type IS TABLE OF employees.employee_id%TYPE; t_employees t_employee_type := t_employee_type(); BEGIN <<process_employees>> FOR i IN 1..t_employees.COUNT() LOOP sys.dbms_output.put_line(t_employees(i)); -- some processing END LOOP process_employees; END; / ## Example (good) Raises neither an error nor checking whether the array is empty. t_employees.COUNT() always returns a NUMBER (unless the array is not initialized). If the array is empty COUNT() returns 0 and therefore the loop will not be entered. DECLARE TYPE t_employee_type IS TABLE OF employees.employee_id%TYPE; t_employees t_employee_type := t_employee_type(); BEGIN IF t_employees IS NOT NULL THEN <<process_employees>> FOR i IN 1..t_employees.COUNT() LOOP sys.dbms_output.put_line(t_employees(i)); -- some processing END LOOP process_employees; END IF; END; /	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.24632082879543304, "perplexity": 11258.354023776454}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-49/segments/1669446710918.58/warc/CC-MAIN-20221203011523-20221203041523-00785.warc.gz"}
https://www.eolymp.com:443/en/contests/21176/problems/230513	Competitions # Interesting Sum Given a three-digit positive integer n. Find the sum of the largest and the smallest three-digit numbers that can be formed from a permutation of n numbers. #### Input One integer n (100n999). #### Output Print the sum of the largest and the smallest three-digit number. Time limit 1 second Memory limit 128 MiB Input example #1 524 Output example #1 787	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.734973132610321, "perplexity": 1524.7373660705261}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-21/segments/1652662539049.32/warc/CC-MAIN-20220521080921-20220521110921-00121.warc.gz"}
https://hal.in2p3.fr/in2p3-00087373	# Gamma and Cosmic-Ray Tests of Special Relativity Abstract : Lorentz symmetry violation (LSV) at Planck scale can be tested (see e.g. physics/0003080) through ultra-high energy cosmic rays (UHECR). In a deformed Lorentz symmetry (DLS) pattern where the effective LSV parameter varies like the square of the momentum scale (quadratically deformed relativistic kinematics, QDRK), a 10E-6 LSV at Planck scale would be enough to produce observable effects on the properties of cosmic rays at the 10E20 eV scale: absence of GZK cutoff, stability of unstable particles, lower interaction rates, kinematical failure of any parton model and of standard formulae for Lorentz contraction and time dilation... Its phenomenological implications are compatible with existing data. If the effective LSV parameter is taken to vary linearly with the momentum scale (linearly deformed relativistic kinematics, LDRK), a LSV at Planck scale larger than 10E-7 eV seems to lead to contradictions with data above TeV energies. Consequences are important for high-energy gamma-ray experiments, as well as for high-energy cosmic rays and gravitational waves. Document type : Conference papers Domain : http://hal.in2p3.fr/in2p3-00087373 Contributor : Dominique Girod Connect in order to contact the contributor Submitted on : Monday, July 24, 2006 - 10:11:54 AM Last modification on : Friday, November 6, 2020 - 3:26:28 AM ### Citation L. Gonzalez-Mestres. Gamma and Cosmic-Ray Tests of Special Relativity. International Symposium on High Energy Gamma-Ray Astronomy, Jun 2000, Heidelberg, Germany. pp.878-881. ⟨in2p3-00087373⟩ Record views	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8793900012969971, "perplexity": 4798.188990196567}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-27/segments/1656103516990.28/warc/CC-MAIN-20220628111602-20220628141602-00535.warc.gz"}
https://mirror2image.wordpress.com/2011/05/02/	# Mirror Image ## Robust estimators III: Into the deep Cauchy estimator have some nice properties (Gonzales et al “Statistically-Efficient Filtering in Impulsive Environments: Weighted Myriad Filter” 2002): By tuning $\gamma$ in $\psi(x) = \frac{x}{\gamma^2+ x^2}$ it can approximate either least squares (big $\gamma$), or mode – maximum of histogram – of sample set (small $\gamma$). For small $\gamma$ estimator behave the same way as power law distribution estimator with small $\alpha$. Another property is that for several measurements with different scales $\gamma_i$ estimator of their sum will be simple $\psi(x) = \frac{x}{(\sum \gamma_i)^2+ x^2}$ which is convenient for estimation of random walks I heard convulsion in the sky, And flight of angel hosts on high, And monsters moving in the deep Those verses from The Prophet by A.Pushkin could be seen as metaphor of profound mathematical insight, encompassing bifurcations, higher dimensional algebra and murky depths of statistics. I now intend to dive deeper into of statistics – toward “data depth”. Data depth is a generalization of median concept to multidimensional data. Remind you that median can be seen either as order parameter – value dividing the higher half of measurements from lower, or geometrically, as the minimum of $L_1$ norm. Second approach lead to geometric median, about which I already talked about. First approach to generalizations of median is to try to apply order statistics to multidimensional vectors.The idea is to make some kind of partial order for n-dimensional points – “depth” of points, and to choose as the analog of median the point of maximum depth. Basically all data depth concepts define “depth” as some characterization of how deep points are reside inside the point cloud. Historically first and easiest to understand was convex hull approach – make convex hull of data set, assign points in the hull depth 1, remove it, get convex hull of points remained inside, assign new hull depth 2, remove etc.; repeat until there is no point inside last convex hull. Later Tukey introduce similar “halfspace depth” concept – for each point X find the minimum number of points which could be cut from the dataset by plane through the point X. That number count as depth(see the nice overview of those and other geometrical definition of depth at Greg Aloupis page) In 2002 Mizera introduced “global depth”, which is less geometric and more statistical. It start with assumption of some loss function (“criterial function” in Mizera definition) $F(x_i, \theta)$ of measurement set $x_i$. This function could be(but not necessary) cumulative probability distribution. Now for two parameters $\theta_1$ and $\theta_2$, $\theta_1$ is more fit with respect $A \subset N$ if for all $i \in A$ $F(x_i, \theta_1) > F(x_i, \theta_2)$. $\hat{\theta}$ is weakly optimal with respect to $A$ if there is nor better fit parameter with respect to $A$. At last global depth of $\theta$ is the minimum possible size of $A$ such that $\theta$ is not weakly optimal with respect to $N \setminus A$ – reminder of measurements. In other words global depth is minimum number of measurements which should be removed for $\theta$ stop being weakly optimal. Global depth is not easy to calculate or visualize, so Mizera introduce more simple concept – tangent depth. Tangent depth defined as $min_{\parallel u\parallel=1}\mid \{ i: u^T \bigtriangledown_{\theta} F(x_i) \geq 0 \}\mid$. What does it mean? Tangent depth is minimum number of “bad” points – such points that for specific direction loss function for themis growing. Those definitions of “data depth” allow for another type of estimator, based not on likelihood, but on order statisticsmaximum depth estimators. The advantage of those estimators is robustness(breakdown point ~25%-33%) and disadvantage – low precision (high bias). So I wouldn’t use them for precise estimation, but for sanity check or initial approximation. In some cases they could be computationally more cheap than M-estimators. As useful side effect they also give some insight into structure of dataset(it seems originally maximum depth estimators was seen as data visualization tool). Depth could be good criterion for outliers rejection. Disclaimer: while I had very positive experience with Cauchy estimator, data depth is a new thing for me.I have yet to see how useful it could be for computer vision related problems.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 26, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6143224239349365, "perplexity": 1443.3962600626896}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-30/segments/1563195524679.39/warc/CC-MAIN-20190716160315-20190716182315-00459.warc.gz"}
https://ncas-cms.github.io/cf-python/method/cf.Field.set_construct.html	# cf.Field.set_construct¶ Field.set_construct(construct, key=None, axes=None, set_axes=True, copy=True, autocyclic={})[source] When inserting a construct with data, the domain axes constructs spanned by the data are either inferred, or specified with the axes parameter. For a dimension coordinate construct, an existing dimension coordinate construct is discarded if it spans the same domain axis construct (since only one dimension coordinate construct can be associated with a given domain axis construct). New in version 3.0.0. Parameters construct: The metadata construct to be inserted. key: str, optional The construct identifier to be used for the construct. If not set then a new, unique identifier is created automatically. If the identifier already exists then the existing construct will be replaced. Parameter example: key='cellmeasure0' axes: (sequence of) str or int, optional Set the domain axes constructs that are spanned by the construct’s data. If unset, and the set_axes parameter is True, then an attempt will be made to assign existing domain axis constructs to the data. The contents of the axes parameter is mapped to domain axis constructs by translating each element into a domain axis construct key via the domain_axis method. Parameter example: axes='domainaxis1' Parameter example: axes='X' Parameter example: axes=['latitude'] Parameter example: axes=['X', 'longitude'] Parameter example: axes=[1, 0] set_axes: bool, optional If False then do not set the domain axes constructs that are spanned by the data, even if the axes parameter has been set. By default the axes are set either according to the axes parameter, or an attempt will be made to assign existing domain axis constructs to the data. copy: bool, optional If True then set a copy of the construct. By default the construct is copied. autocyclic: dict, optional Additional parameters for optimizing the operation, relating to coordinate periodicity and cyclicity. See the code for details. New in version 3.9.0. Returns str The construct identifier for the construct. Examples >>> key = f.set_construct(c) >>> key = f.set_construct(c, copy=False) >>> key = f.set_construct(c, axes='domainaxis2') >>> key = f.set_construct(c, key='cellmeasure0')	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.1768093854188919, "perplexity": 6757.721127162189}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-40/segments/1664030335303.67/warc/CC-MAIN-20220929003121-20220929033121-00658.warc.gz"}
https://labs.tib.eu/arxiv/?author=P.%20Timmer	• ### Intrinsic limits on resolutions in muon- and electron-neutrino charged-current events in the KM3NeT/ORCA detector(1612.05621) May 19, 2017 hep-ph, hep-ex, physics.ins-det Studying atmospheric neutrino oscillations in the few-GeV range with a multimegaton detector promises to determine the neutrino mass hierarchy. This is the main science goal pursued by the future KM3NeT/ORCA water Cherenkov detector in the Mediterranean Sea. In this paper, the processes that limit the obtainable resolution in both energy and direction in charged-current neutrino events in the ORCA detector are investigated. These processes include the composition of the hadronic fragmentation products, the subsequent particle propagation and the photon-sampling fraction of the detector. GEANT simulations of neutrino interactions in seawater produced by GENIE are used to study the effects in the 1 - 20 GeV range. It is found that fluctuations in the hadronic cascade in conjunction with the variation of the inelasticity y are most detrimental to the resolutions. The effect of limited photon sampling in the detector is of significantly less importance. These results will therefore also be applicable to similar detectors/media, such as those in ice. • The main objectives of the KM3NeT Collaboration are i) the discovery and subsequent observation of high-energy neutrino sources in the Universe and ii) the determination of the mass hierarchy of neutrinos. These objectives are strongly motivated by two recent important discoveries, namely: 1) The high-energy astrophysical neutrino signal reported by IceCube and 2) the sizable contribution of electron neutrinos to the third neutrino mass eigenstate as reported by Daya Bay, Reno and others. To meet these objectives, the KM3NeT Collaboration plans to build a new Research Infrastructure consisting of a network of deep-sea neutrino telescopes in the Mediterranean Sea. A phased and distributed implementation is pursued which maximises the access to regional funds, the availability of human resources and the synergetic opportunities for the earth and sea sciences community. Three suitable deep-sea sites are identified, namely off-shore Toulon (France), Capo Passero (Italy) and Pylos (Greece). The infrastructure will consist of three so-called building blocks. A building block comprises 115 strings, each string comprises 18 optical modules and each optical module comprises 31 photo-multiplier tubes. Each building block thus constitutes a 3-dimensional array of photo sensors that can be used to detect the Cherenkov light produced by relativistic particles emerging from neutrino interactions. Two building blocks will be configured to fully explore the IceCube signal with different methodology, improved resolution and complementary field of view, including the Galactic plane. One building block will be configured to precisely measure atmospheric neutrino oscillations. • A prototype detection unit of the KM3NeT deep-sea neutrino telescope has been installed at 3500m depth 80km offshore the Italian coast. KM3NeT in its final configuration will contain several hundreds of detection units. Each detection unit is a mechanical structure anchored to the sea floor, held vertical by a submerged buoy and supporting optical modules for the detection of Cherenkov light emitted by charged secondary particles emerging from neutrino interactions. This prototype string implements three optical modules with 31 photomultiplier tubes each. These optical modules were developed by the KM3NeT Collaboration to enhance the detection capability of neutrino interactions. The prototype detection unit was operated since its deployment in May 2014 until its decommissioning in July 2015. Reconstruction of the particle trajectories from the data requires a nanosecond accuracy in the time calibration. A procedure for relative time calibration of the photomultiplier tubes contained in each optical module is described. This procedure is based on the measured coincidences produced in the sea by the 40K background light and can easily be expanded to a detector with several thousands of optical modules. The time offsets between the different optical modules are obtained using LED nanobeacons mounted inside them. A set of data corresponding to 600 hours of livetime was analysed. The results show good agreement with Monte Carlo simulations of the expected optical background and the signal from atmospheric muons. An almost background-free sample of muons was selected by filtering the time correlated signals on all the three optical modules. The zenith angle of the selected muons was reconstructed with a precision of about 3{\deg}. • The first prototype of a photo-detection unit of the future KM3NeT neutrino telescope has been deployed in the deep waters of the Mediterranean Sea. This digital optical module has a novel design with a very large photocathode area segmented by the use of 31 three inch photomultiplier tubes. It has been integrated in the ANTARES detector for in-situ testing and validation. This paper reports on the first months of data taking and rate measurements. The analysis results highlight the capabilities of the new module design in terms of background suppression and signal recognition. The directionality of the optical module enables the recognition of multiple Cherenkov photons from the same $^{40}$K decay and the localization bioluminescent activity in the neighbourhood. The single unit can cleanly identify atmospheric muons and provide sensitivity to the muon arrival directions.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7440928220748901, "perplexity": 1778.1975320359834}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-50/segments/1606141674082.61/warc/CC-MAIN-20201201104718-20201201134718-00691.warc.gz"}
http://cms.math.ca/cjm/msc/17B66	Canadian Mathematical Society www.cms.math.ca location: Publications → journals Search results Search: MSC category 17B66 ( Lie algebras of vector fields and related (super) algebras ) Expand all Collapse all Results 1 - 2 of 2 1. CJM 2007 (vol 59 pp. 712) Billig, Yuly Jet Modules In this paper we classify indecomposable modules for the Lie algebra of vector fields on a torus that admit a compatible action of the algebra of functions. An important family of such modules is given by spaces of jets of tensor fields. Categories:17B66, 58A20 2. CJM 1997 (vol 49 pp. 119) Osborn, J. Marshall Automorphisms of the Lie algebras $W^*$ in characteristic $0$ No abstract. Categories:17B40, 17B65, 17B66, 17B68, 17B70 top of page \| contact us \| privacy \| site map \| © Canadian Mathematical Society, 2016 : https://cms.math.ca/	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.4172007739543915, "perplexity": 2739.0029903914706}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-26/segments/1466783399385.17/warc/CC-MAIN-20160624154959-00168-ip-10-164-35-72.ec2.internal.warc.gz"}
https://www.ann-geophys.net/36/381/2018/angeo-36-381-2018.html	Journal topic Ann. Geophys., 36, 381–404, 2018 https://doi.org/10.5194/angeo-36-381-2018 Special issue: Space weather connections to near-Earth space and the... Ann. Geophys., 36, 381–404, 2018 https://doi.org/10.5194/angeo-36-381-2018 Regular paper 16 Mar 2018 Regular paper \| 16 Mar 2018 # Variability and trend in ozone over the southern tropics and subtropics Variability and trend in ozone over the southern tropics and subtropics Abdoulwahab Mohamed Toihir1, Thierry Portafaix1, Venkataraman Sivakumar2, Hassan Bencherif1,2, Andréa Pazmiño3, and Nelson Bègue1 Abdoulwahab Mohamed Toihir et al. • 1Laboratoire de l'Atmosphère et des Cyclones, Université de La Réunion, St-Denis, Réunion Island, France • 2Discipline of Physics, School of Chemistry and Physics, University of KwaZulu-Natal, Durban, South Africa • 3Laboratoire Atmosphères, Milieux, Observations Spatiales, CNRS, Université Versailles Saint Quentin, Guyancourt, France Correspondence: Abdoulwahab Mohamed Toihir (fahardinetoihr@gmail.com) Abstract Long-term variability in ozone trends was assessed over eight Southern Hemisphere tropical and subtropical sites (Natal, Nairobi, Ascension Island, Java, Samoa, Fiji, Reunion and Irene), using total column ozone data (TCO) and vertical ozone profiles (altitude range 15–30 km) recorded during the period January 1998–December 2012. The TCO datasets were constructed by combination of satellite data (OMI and TOMS) and ground-based observations recorded using Dobson and SAOZ spectrometers. Vertical ozone profiles were obtained from balloon-sonde experiments which were operated within the framework of the SHADOZ network. The analysis in this study was performed using the Trend-Run model. This is a multivariate regression model based on the principle of separating the variations of ozone time series into a sum of several forcings (annual and semi-annual oscillations, QBO (Quasi-Biennial Oscillation), ENSO, 11-year solar cycle) that account for most of its variability. The trend value is calculated based on the slope of a normalized linear function which is one of the forcing parameters included in the model. Three regions were defined as follows: equatorial (0–10 S), tropical (10–20 S) and subtropical (20–30 S). Results obtained indicate that ozone variability is dominated by seasonal and quasi-biennial oscillations. The ENSO contribution is observed to be significant in the tropical lower stratosphere and especially over the Pacific sites (Samoa and Java). The annual cycle of ozone is observed to be the most dominant mode of variability for all the sites and presents a meridional signature with a maximum over the subtropics, while semi-annual and quasi-biannual ozone modes are more apparent over the equatorial region, and their magnitude decreases southward. The ozone variation mode linked to the QBO signal is observed between altitudes of 20 and 28 km. Over the equatorial zone there is a strong signal at ∼26km, where 58 % ±2 % of total ozone variability is explained by the effect of QBO. Annual ozone oscillations are more apparent at two different altitude ranges (below 24 km and in the 27–30 km altitude band) over the tropical and subtropical regions, while the semi-annual oscillations are more significant over the 27–30 km altitude range in the tropical and equatorial regions. The estimated trend in TCO is positive and not significant and corresponds to a variation of $\sim \mathrm{1.34}±\mathrm{0.50}$ % decade−1 (averaged over the three regions). The trend estimated within the equatorial region (0–15 S) is less than 1 % per decade, while it is assessed at more than 1.5 % decade−1 for all the sites located southward of 17 S. With regard to the vertical distribution of trend estimates, a positive trend in ozone concentration is obtained in the 22–30 km altitude range, while a delay in ozone improvement is apparent in the UT–LS (upper troposphere–lower stratosphere) below 22 km. This is especially noticeable at approximately 19 km, where a negative value is observed in the tropical regions. 1 Introduction Atmospheric ozone protects all life on earth from damaging solar ultraviolet radiation. About 90 % of ozone is observed in the stratosphere where it is strongly influenced by various photochemical and dynamical processes. Three processes determine stratospheric ozone distribution and concentration, namely ozone production, destruction and transport. While ozone concentration in the upper stratosphere (35–50 km) is primary determined by the processes of photochemical creation and destruction, ozone concentration in the lower and middle stratosphere (below 30 km) is strongly affected by transport (Portafaix et al., 2003; Bencherif et al., 2007, 2011; El-Amraoui et al., 2010). Ozone is formed primarily in tropical regions as a result of a reaction between atmospheric oxygen and the ultraviolet component of incident solar radiation; it is then subsequently transported and distributed to higher latitudes following the Brewer–Dobson circulation (Weber et al., 2011). The combination of these processes contributes to the overall spatiotemporal distribution and variability of atmospheric ozone. The variability in ozone levels also depends on several dynamic proxies and the chemical evolution of ozone-depleting substances (ODS). Since 1980, anthropogenic ODS emissions reaching the stratosphere have led to a decline in global ozone concentration (Sinnhuber et al., 2009). However, recent observations have indicated that the decreasing trend in stratospheric ozone has been halted from the mid-90s (1995–1996), and an upward trend has been observed at 60 N–60 S since 1997 (Jones et al., 2009; Nair et al., 2013; Kyrölä et al., 2013; Chehade et al., 2014; Eckert et al., 2014). This increasing trend in stratospheric ozone is associated with a decrease in atmospheric chlorine and bromine compounds as a direct result of the Montreal Protocol which regulates ODS emission (United Nation Environment Program, UNEP 2009). From the present and going forward, this increase in stratospheric ozone is expected to begin to be more widely observable on a global scale (Steinbrecht et al., 2009; WMO (World Meteorological Organization, 2010, 2014). However, Butler et al. (2016) have shown that tropical ozone will not recover to typical levels of the 1960s by the end of the 21st century. Depending on the specific processes involved, climate change can induce modifications in the stratosphere that can delay or accelerate ozone recovery. Greenhouse gas (GHG) induced stratospheric cooling should lead to increased photochemical ozone production and slower destruction rates via the Chapman cycle (Jonsson et al., 2009). Furthermore, and with direct relevance to the region under study, acceleration of the Brewer–Dobson circulation due to tropospheric warming is thought to lead to decreases/increases in tropical/middle latitude stratospheric ozone. It is important to create a consistent and reliable dataset in order to quantify ozone variability, to estimate trends and to validate models used for predicting future evolution of ozone levels (Randel and Thompson, 2011). The work presented here investigates the period 1998–2012 where an increase in stratospheric ozone is expected to be measurable. The aim of this study is to investigate the current behaviour of seasonal and inter-annual ozone variability over the southern tropics and subtropics and to analyse whether the expected ozone recovery is effective in the selected study region and at which altitude level ozone increase is significant. The WMO (2014) reported a divergence in ozone profile trends computed from individual instruments in the lower stratospheric tropical region. Sioris et al. (2014) showed a declining ozone trend for OSIRIS data, while Gebhardt et al. (2014) reported an increasing ozone trend using measurements from the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) and Aura Microwave Limb Sounder (MLS) instruments. Therefore, a study of ozone levels at tropical latitudes and present in the lower and middle stratosphere is of paramount importance. The trend analysis of two types of ozone data is relevant with respect to this study, namely, total column ozone (TCO) and vertical ozone profile measurements. While the TCO analysis offers the best way to provide information on ozone variability for the complete ozone layer, profile analysis allows for the investigation of ozone behaviour at different altitude levels (Nair et al., 2013). Ozone profile measurement is usually achieved by ground-based lidar instruments, satellite observation and ozonesondes. However, observation by ozonesonde is often preferred due to its high vertical resolution. SHADOZ (Southern Hemisphere Additional Ozonesonde) is the only network which provides ozonesonde profiles over the southern tropics and subtropics. It has a precision of approximately 5 % with a vertical resolution between 50 and 100 m (Thompson et al., 2003a). Previously radiosonde observations from SHADOZ networks have been used to validate tropospheric ozone observations obtained from satellites (Ziemke et al., 2006, 2011), to study the stratospheric altitude profile of ozone and water vapour in the Southern Hemisphere (Sivakumar et al., 2010), to investigate the dynamic characteristics of the Southern Hemisphere tropopause (Sivakumar et al., 2006, 2011; Thompson et al., 2012), to study seasonal and inter-annual variation of ozone and temperature between the atmospheric boundary layer and the middle stratosphere (Thompson et al., 2003b; Diab et al., 2004; Sivakumar et al., 2007; Bègue et al., 2010; Mze et al., 2010) and to analyse the variability and trends in ozone and temperature in the tropics (Lee et al., 2010; Randel and Thompson, 2011). In this paper, SHADOZ profiles recorded at eight Southern Hemisphere stations were used to investigate seasonal and inter-annual variability of ozone and to estimate the trends at different stratospheric pressure levels. The TCO measurements were performed based on Dobson and SAOZ (Système d'Analyse par Observation Zénithale) ground-based instruments (Pommerau and Goutail, 1988; Dobson, 1931). However, ground-based data were only available for three of the eight stations considered in this work. Satellite observations were therefore used in order to complete ground-based observations, particularly at tropical sites (Nairobi, Java, Samoa, Fiji and Ascension Island) where ground-based datasets were incomplete or non-existent. The chosen satellite datasets are OMI (Ozone Monitoring Instrument) and TOMS (Total Ozone Mapping Spectrometer) (McPeters et al., 1998; Bhartia, 2002) because of their high-quality ozone data. The TOMS instrument has facilitated the recording of long-term ozone measurements on both global and regional scales. TOMS instruments were successfully flown aboard several satellites from 1978 to 2005, with the latest instrument aboard the Earth Probe (EP) satellite operational from July 1996 to December 2005. In the framework of the EOS (Earth Observing System) programme, TOMS was replaced by the OMI instrument launched onboard the Aura satellite (July 2004 and operational to the present). The combined TCO data recorded from ground-based instrumentation and satellites were used to investigate ozone variability and trends over the selected study region. Data analysis was conducted using a multivariate regression model known as Trend-Run (Bencherif et al., 2006; Bègue et al., 2010). Multivariate regression models are considered powerful tools to study stratospheric ozone variability and trends (Randel and Thompson, 2011; Kyrölä et al., 2013; Nair et al., 2013; Bourassa et al., 2014; Gebhardt et al., 2014; Eckert et al., 2014). In these models, the choice of proxies is important as the indexes of these proxies are often chosen based on atmospheric forcings that have been historically accepted as having an influence on ozone variability (Damadeo et al., 2014). Butchart et al. (2003) analysed equatorial ozone variability based on a coupled stratospheric chemistry and transport model. They observed a strong QBO (Quasi-Biennial Oscillation) signal in total column ozone variability with an observed correlation between the stratospheric ozone anomaly and the westerly wind distribution higher than 50 %. Brunner et al. (2006) demonstrated the existence of a strong QBO signal in ozone variability throughout most of the lower stratosphere, with a peak amplitude in the tropics of the order of 10–20 %. The ozone–QBO relationship has been discussed in several papers, as well as ENSO (El Niño–Southern Oscillation) influence on ozone variability. ENSO events are linked to coherent variations of the ozone zonal mean in the tropical lower stratosphere, tied to fluctuations in tropical upwelling (Randel et al., 2009). Randel and Thompson (2011) observed a negative signal in ozone variability exhibited by the ENSO index with a magnitude of around 6 % in the lower stratosphere. It is known that solar flux has also contributed to the timescale variability of ozone (Zerefos et al., 1997; Randel and Wu, 2007). Several studies have shown that when the solar activity is high, larger amounts of ozone are formed in the upper stratosphere. Maximum ozone levels should therefore occur during periods of high solar activity (Haigh, 1994; Labitzke et al., 2002; Gray et al., 2010). However, Efstathiou and Varotsos (2013) demonstrated that the effect of the solar cycle response on total column ozone was caused by dynamical changes which were related to solar activity. It has been reported by Austin et al. (2008) that the solar flux response to long-term ozone variation is around 2.5 %, with a maximum in the tropics. Soukharev and Hood (2006) have reported that the solar cycle response to ozone variability is positive and statistically significant in the lower and upper stratosphere but insignificant over the middle stratosphere. In this investigation, QBO, ENSO and solar flux proxies were used as inputs in the Trend-Run model to simulate inter-annual ozone variation over the selected study region. Annual and semi-annual cycles were taken into account in order to quantify their impact on seasonal and annual variability. This paper is organized as follows: Sect. 2 describes data and instrumentation used in this investigation and Sect. 3 describes the Trend-Run model and presents the method adopted for data analysis. Results detailing ozone trends and variability are presented in Sect. 4. Section 5 concludes this investigation with a summary of important results. 2 Ozone data source ## 2.1 TCO from ground-based observations The ground-based instruments employed in this investigation are Dobson and SAOZ spectrometers. TCO data obtained from these instruments are available from the World Ozone Ultraviolet radiation Data Centre (WOUDC, http://www.woudc.org/) and the Network for the Detection of Atmospheric Composition Change (NDACC, http://www.ndsc.ncep.noaa.gov/) websites. The Dobson spectrophotometer was the first instrument developed to measure TCO (Dobson, 1931) and the first TCO measurement was made in 1926 at Arosa, Switzerland. Dobson spectrophotometers were initially distributed at northern middle latitudes and then later moved to include observations in the Southern Hemisphere. At present, ground-based ozone measurements using Dobson spectrophotometers are widespread globally. The Dobson network currently consists of more than 80 stations, with most instruments calibrated following the standard reference D 83 which is recognized by the ESRL (Earth System Research Laboratory) and the WMO (Komhyr et al., 1993). The relative uncertainty associated with the Dobson instrument has been assessed at approximately 2 % (Basher, 1985). In this work, TCO recorded from Dobson instruments located at Natal (equatorial site: 35.38 W, 5.42 S) and Irene (subtropical site: 28.22 E, 25.90 S) was used. The measurement principle of the Dobson spectrometer is based on a UV radiation differential absorption technique in a wavelength range where ozone is strongly absorbed compared to one where ozone is weakly absorbed. Total column ozone observations are performed by measuring the relative intensities at selected pairs of ultraviolet wavelengths. The most used wavelengths are the double pair (305.5/325.5 nm and 317.6/339.8 nm) and (311.45/332.4 nm and 316.6/339.8 nm) emanating from the Sun, moon or zenith sky (WMO, 2003, 2008). For further information regarding the Dobson spectrometer functioning, the reader may refer to the studies outlined by Komhyr et al. (1989, 1993). The SAOZ spectrometer was developed by the CNRS (Centre National de la Recherche Scientifique). In 1988, it was used for the first time at Dumont d'Urville (Antarctica) to measure stratospheric ozone during the polar winter. SAOZ is a passive remote sensing instrument operating in the visible and ultraviolet ranges. It measures the sunlight scattered from the zenith sky in the wavelength range between 300 and 600 nm. The SAOZ instrument is able to retrieve the total column of ozone and NO2 in the visible band with an average spectral resolution of around 1 nm using the differential optical absorption spectroscopy (DOAS) technique. At Reunion, a SAOZ instrument has been operational since 1993 within the framework of NDACC. SAOZ ozone measurements have been performed during sunrise and sunset with a precision of <5 % and an accuracy of <6 % (Hendrick et al., 2011). In the present work, the daily average of TCO was taken as the mean value of sunrise and sunset observations (86–91 SZA) recorded at Reunion. SAOZ TCO measurements have been shown to be in good agreement with OMI-TOMS (Pastel et al., 2014; Toihir et al., 2013) and Infrared Atmospheric Sounding Interferometer (IASI; Toihir et al., 2015a) measurements. Further details can be found in Pazmiño (2010). ## 2.2 TCO from satellite observations Satellite data employed in this investigation were obtained from the EP-TOMS and OMI-TOMS L2 data products. The EP-TOMS data product is the most recent (1996–2005) and the duration of other important satellite observations include the TOMS instrument onboard the Nimbus-7 satellite (1978–1993), Meteor-3 (1991–1994) and ADEOS (1996–1997). On 2 July 1996, EP-TOMS was the only instrument launched onboard the Earth Probe satellite. It was launched into a polar orbit with an initial altitude of 500 km and an inclination angle of 98. However, after the failure of the ADEOS satellite, the EP-TOMS instrument was raised to an altitude of 739 km with an inclination angle of 98.4 This was done in order to provide complete global coverage of ozone and other species such as sulfur dioxide. The TOMS instrument is a downward nadir viewing spectrometer that measures both incoming solar energy and backscatter ultraviolet radiance at six different wavelengths (379.95, 359.88, 339.66, 331.06, 317.35 and 312.34 nm) with a spatial resolution of 50 km×50 km. The instrument uses a single monochromator and a scanning mirror to sample the backscattered solar ultraviolet radiation at 35 sample points at 3 intervals along a line perpendicular to the orbital plane (Bramstedt et al., 2003). TOMS data used in this work are an overpass product and are available online from the website link http://acdisc.gsfc.nasa.gov/opendap/EarthProbe_TOMS_Level3/contents.html. For more details on the TOMS instrument and the associated data product, the reader may refer to the EP-TOMS data product user guide document (McPeters et al., 1998). As previously mentioned, the EP-TOMS instrument was operational from July 1996 to December 2005. TCO from TOMS was therefore combined with that from OMI recorded overpass for the eight selected investigation sites in order to produce a complete ozone dataset running to December 2012. Two OMI L2 data products are available: OMI-DOAS and OMI-TOMS. However, the OMI-TOMS L2 product was chosen for this investigation due to its good agreement with the EP-TOMS data product (Toihir et al., 2014). OMI is a compact nadir viewing instrument launched aboard the Aura satellite in July 2004 into a near-polar helio-synchronous orbit at approximately 705 km in altitude. OMI operates at a spectral resolution within 0.5 nm in three spectral regions referred to as UV-1, UV-2 and VIS. In terms of spatial coverage, its viewing angle is 57 under a swath width of 2600 km. The ground pixel size of each scan is 13×24km2 in the UV-2 (310–365 nm) and visible (350–500 nm) channels, and 13 km×48 km for the UV-1 (270–310 nm) channel. OMI data used in this work are overpass L2 products and are accessible from http://avdc.gsfc.nasa.gov/pub/data/satellite/Aura/OMI/V03/L2OVP/. OMI-TOMS ozone data are retrieved based on two wavelengths (317.5 and 331.2 nm are applicable under most conditions, while 331.2 and 360 nm are used for conditions of high ozone concentration and high solar zenith angle). The L2 product has a precision of ∼3 % and has shown good agreement with Dobson and SAOZ measurements over the southern tropics and subtropics (Toihir et al., 2013, 2015a). Further details relating to the OMI instrument and mode of operation can be found in the OMI Algorithm Theoretical Basis Document Volume II (Bhartia, 2002). ## 2.3 Ozone profiles from the SHADOZ network Balloon-borne electrochemical concentration cell (ECC) ozonesonde devices were used to provide profile ozone measurements over the eight stations (Nairobi, Ascension Island, Java, Samoa, Fiji, Natal, Reunion and Irene) investigated in this work. These stations form part of the SHADOZ network. The geographical location of each site is illustrated in Fig. 1, while geographical coordinates and altitude a.s.l. are given in Table 1. Equipped with radiosondes for temperature, humidity and pressure measurements, the ECC ozonesonde provides vertical profiles with a resolution between 50 and 100 m from ground to the altitude where balloon burst occurs (∼26–32 km). The precisions of SHADOZ measurements have been evaluated to be ∼5 % (Thompson et al., 2003b). Further details on ECC ozonesonde instrument validation, operating mode and algorithm used for ozone partial pressure (in mPa) retrieval in each of the SHADOZ stations can be obtained from Thompson et al. (2003a, 2007) and Smit et al. (2007). In this work, analysis of vertical ozone variability was performed using SHADOZ profiles recorded over 15 years (1998–2012). These data are available from http://croc.gsfc.nasa.gov/shadoz/. The frequency of SHADOZ observations is between one and six balloon launches per month. The monthly mean profiles for a given station were taken as the average of recorded profiles during the month for that station. Figure 1Geolocation of the SHADOZ sites selected for this investigation. Table 1Geolocation and mean sea level (MSL) of stations investigated in this study. 3 Data analysis ## 3.1 Methodology Prior to analysis of TCO variability and trends, preliminary work was completed in order to create a reliable ozone dataset for each station by merging different available measurements. The first combination exercise was performed on satellite data (TCO form OMI and TOMS) by using the monthly values of ozone recorded during the overlap observation period of the two satellites (October 2004–December 2005). The relative difference (RD) between TOMS and OMI with respect to OMI observation was calculated for individual sites as follows: $\begin{array}{}\text{(1)}& {\text{RD}}_{m}=\mathrm{100}×\frac{{\text{TOMS}}_{m}-{\text{OMI}}_{m}}{{\text{OMI}}_{m}},\end{array}$ where “m” is the month in which both OMI and TOMS observations were performed. After assessing the relative difference, the bias and root mean square (rms) associated with the difference were calculated. For further details outlining the method used to calculate bias and rms, see Toihir et al. (2015a), Toihir et al. (2015b) and Anton et al. (2011). The results obtained for each individual site are presented in Table 2. The recorded biases between TOMS and OMI are positive, thereby indicating an overestimation of TOMS total column ozone with respect to OMI. However, the bias is less than 2.5 % and correlation coefficients (C) between OMI and TOMS are higher than 0.9 (see column 4 of Table 2); it is therefore reasonable to combine the two observations. As OMI measurements recorded during the study period for the chosen sites show better agreement with ground-based (Dobson and SAOZ) measurements than TOMS (see Toihir, 2016, chapter 2), the combination of OMI and TOMS was performed using the OMI observations as a reference. The data combination follows two steps: the first step consists of adjusting the TOMS dataset (January 1998 to December 2005) with respect to OMI by using the obtained rms. The absolute rms is considered the mean systematic error in Dobson units between TOMS and OMI. As TOMS ozone values are always higher than OMI values, TOMS time series (1996–2005) can be adjusted to OMI measurements as follows: $\begin{array}{}\text{(2)}& {\text{TOMS}}_{\text{adjusted}}\left(m\right)=\text{TOMS}\left(m\right)+\text{rms}.\end{array}$ The second step is to average the measurements from OMI with the adjusted TOMS measurements recorded during the overlap observation period of the two satellites. Table 2The computed bias, rms (root mean square) and correlation coefficient C observed between OMI and TOMS for individual stations during the period from August 2004 to December 2006. Figure 2 presents the time evolution of monthly mean TCO measurements over Reunion. Blue and black curves represent TOMS and OMI data respectively. Figure 2 highlights the existing good agreement between both TOMS and OMI observations, with similar results being reported in Toihir et al. (2014). The merged satellite time-evolution data are shown as a dotted red line in Fig. 2. The combination of the above satellite data is performed for each site under study by using the rms obtained for the site (see Table 2). Figure 2Monthly mean of TCO as measured by TOMS (blue) and OMI (black) over Reunion. The combined measurements of OMI and TOMS data are indicated by the dashed red line. A second method to validate this data combination consisted of a comparison of satellite data with available ground-based measurements. TCO from ground-based instruments were available at Natal, Reunion and Irene stations and ground-based and TOMS adjusted-OMI time evolutions of the TCO monthly mean over these stations are shown in Fig. 3. Figure 3 illustrates the fact that satellite data show good agreement with ground-based observation before and after the simultaneous period of TOMS and OMI observations, thereby indicating a good agreement between the merged satellite and ground-based data. Correlation coefficients C between the merged satellite measurements and ground-based data are 0.88, 0.90 and 0.97 over Natal, Irene and Reunion respectively. The obtained relative bias between satellite and ground-based observation with respect to the ground-based observation is assessed to be less than 2.5 % for individual sites. Due to this consistency existing between merged satellite data and ground-based measurements, the study of TCO variability and trends was performed using the merged satellite data for sites where no ground-based measurements existed. In the case of three stations where ground-based measurements were available, satellite and ground-based measurements were merged by adjusting the satellite dataset with respect to ground-based data. Figure 3Temporal evolution of TCO from ground-based spectrometers (blue) compared with that obtained by a combination of TOMS and OMI TCO overpass over Natal (a), Reunion (b) and Irene (c) for the period January 1998 to December 2012. The study of vertical ozone variability and associated trends was performed based on SHADOZ ozone profile data available for the eight selected sites. In this work, 3431 profiles were examined. The number of examined profiles and the temporal coverage of data recorded for individual stations are presented in Table 3. Although the eight SHADOZ stations started measurements in 1998, the temporal coverage of the data recorded and the number of observations at each station differ. For example, observations at Ascension Island were discontinued in 2010, while no data were available in Natal during 2012. Irene SHADOZ observations were discontinued in 2006 and restarted in November 2012. Considering the discontinuity in observations and the limited number of monthly profiles, monthly data for stations with the same climatological behaviour were averaged (Mzé et al., 2010). Stations were classified into three groups based on low variability in zonal ozone distribution, the proximity of stations and the dynamical structure of the stratosphere (Ziemke et al., 2010). These groupings were near-equatorial (Nairobi, Natal, Java and Ascension Island), tropical (Samoa and Fiji) and subtropical (Reunion and Irene) and corresponded to stations located between latitude bands 0–10 S, 10–20 S and 20–30 S respectively. Geographical coordinates of stations are given in Table 1. Monthly profiles recorded from stations located in the same altitude band were averaged to represent the monthly mean for the selected altitude range. Figure 4 shows the time and height evolution of the constructed monthly mean ozone profile. The top (a), middle (b) and bottom (c) panels represent the monthly vertical distribution of ozone concentration between 15 and 30 km over the equatorial, tropical and subtropical regions respectively. In order to follow a more uniform data processing approach, monthly TCO values for stations from the same latitude range were averaged for specific cases. The constructed TCO time series from the procedure defined above are shown by the blue line in Fig. 5. Figure 4Time–height section of ozone concentration (mol cm−3) obtained by mean monthly profiles recorded over stations located in the equatorial (a), tropical (b) and subtropical (c) regions from January 1998 to December 2012. Table 3Time period and total number of height profiles used in this analysis for selected stations. Figure 5Time evolution of monthly mean total ozone values (blue) over the equatorial (a), tropical (b) and (c) subtropical regions. The black lines represent TCO values as calculated by the Trend-Run model. ## 3.2 Description of the Trend-Run model Trend-Run is a multi-regression model adapted by Reunion University and dedicated to the study of ozone and temperature variability and associated trends (Bencherif et al., 2006; Bègue et al., 2010; Toihir et al., 2014). Input parameters include monthly mean ozone values (in DU for TCO or concentration at a given pressure for high-altitude profiles) and variables that represent a significant contribution to stratospheric ozone variability. Considering the selected region (0–30 S) and the temporal coverage defined in this work (1998–2012), and in order to simplify analysis and interpretation of results, the parameters included in this analysis were QBO, ENSO and solar flux. Note that aerosols constitute a source of uncertainty that may affect TCO variability, notably following a major event such as a volcanic eruption. However, by using the Trend-Run model, Bencherif et al. (2006) and Bègue et al. (2010) showed that volcanic aerosol forcing from the Pinatubo eruption was weak and could be assumed negligible beyond 1996. Aerosol index is therefore not included in the framework of this present study as the ozone time series starts in 1998, 2–3 years after the post-Pinatubo eruption period. In trend calculations, a long-term linear function is generated by the model to characterize the trend index which is used among the model parameters. The trend value is calculated based on the slope of the normalized linear function. As ozone variability is also affected by annual and semi-annual oscillations (AO and SAO), these two parameters were taken into account in terms of model inputs. They may be described by a sinusoidal function as shown below: $\begin{array}{}\text{(3)}& \left\{\begin{array}{l}\text{AO}\left(m\right)=\mathrm{cos}\left(\frac{\mathrm{2}\mathit{\pi }m}{\mathrm{12}}\right)+\mathit{\phi },\\ \text{SAO}\left(m\right)=\mathrm{sin}\left(\frac{\mathrm{2}\mathit{\pi }m}{\mathrm{6}}\right)+\mathit{\phi },\end{array}\right\\end{array}$ where “m” is the monthly temporal parameter and $\mathit{\phi }=\frac{\mathrm{2}\mathit{\pi }I}{\mathrm{180}}$. I is a phasing coefficient between the temporal signal of ozone and the sinusoidal annual or semi-annual function. The ENSO parameter is based on the Multivariate ENSO Index (MEI), while the solar cycle is the solar 10.7 cm radio flux. These two parameters were obtained from the NCEP/NCAR website: http://www.esrl.noaa.gov/psd/data/climateindices/list/. The MEI is defined by positive values during El Niño and negative values for the duration of La Niña. The chosen QBO index is the time series of zonal wind at 30 hPa over Singapore and is available from the following link: http://www.cpc.ncep.noaa.gov/data/indices/qbo.u30.index. ENSO and QBO parameters are phased with respect to ozone time series based on phasing time which define the temporal point where the variable response to ozone is maximum. The index time series of the considered parameters are first normalized and filtered to remove a possible 3-month response. The output geophysical signal Y(z,m) of ozone for a given altitude “z” is modelled as follows: $\begin{array}{}\text{(4)}& \begin{array}{l}Y\left(z,m\right)=C\left(z{\right)}_{\mathrm{1}}+C\left(z{\right)}_{\mathrm{2}}\text{AO}\left(m\right)+C\left(z{\right)}_{\mathrm{3}}\text{SAO}\left(m\right)\\ +C\left(z{\right)}_{\mathrm{4}}\text{SC}\left(m\right)+C\left(z{\right)}_{\mathrm{5}}\text{QBO}\left(m\right)+C\left(z{\right)}_{\mathrm{6}}\text{MEI}\left(m\right)\\ +C\left(z{\right)}_{\mathrm{7}}\text{TREND}\left(m\right)+\mathit{\epsilon }\left(z,m\right),\end{array}\end{array}$ where C(z)(1–7) are regression coefficients representing the weighting of parameterized variables on geophysical signal Y and ε(z,m) is the residual term representing a noise and/or contribution of parameters not included in the model. The regression coefficients are determined based on the least-squares method in order to minimize the sum of the residual squares. It is worth noting that the degree of data independency is assessed through the autocorrelation coefficient φ of the residual term (Bencherif et al., 2006). More details on how φ is calculated for ozone data are found in Portafaix (2003). The uncertainties in coefficient C(z)(1–7) are assessed by taking into account the autocorrelation coefficient and are formulated as follows: $\begin{array}{}\text{(5)}& {\mathit{\sigma }}_{a}^{\mathrm{2}}=v\left(k\right)\cdot {\mathit{\sigma }}_{s}^{\mathrm{2}}\cdot \frac{\mathrm{1}+\mathit{\varphi }}{\mathrm{1}-\mathit{\varphi }},\end{array}$ where ${\mathit{\sigma }}_{s}^{\mathrm{2}}$ and v(k) represent the variance of the residual term and the covariance matrix of the different proxies input in the linear multi-regression model respectively. Equation (5) is used to estimate error associated with trend estimation. The temporal function $C\left(z{\right)}_{p+\mathrm{1}}\cdot {Y}_{p}\left({m}_{\mathrm{1}\to n}\right)$ is defined as the factorized signal of input proxy “P”, and $\left\|C\left(z{\right)}_{p+\mathrm{1}}\right\|\cdot \mathit{\sigma }\left({Y}_{p}\left({m}_{\mathrm{1}\to n}\right)\right)$ is the corresponding SD (Brunner et al., 2006). The contribution of a given parameter to the total variation of inter-annual data is the ratio of a factorized signal sum of squares to the total sum of squares of the inter-annual ozone data. The amplitude of the response of the parameterized parameter (in percentage by unit of the parameter) with respect to the total variance of ozone time series is assessed based on the corresponding regression coefficient. It may be expressed as follows: $\begin{array}{}\text{(6)}& A\left(z{\right)}_{P}=\mathrm{100}×\frac{C\left(z{\right)}_{P+\mathrm{1}}}{C\left(z{\right)}_{\mathrm{1}}}.\end{array}$ A is positive when the temporal signal of the parameter is in phase with the ozone time series, and it is negative in the opposite case. 4 Results and discussion In this investigation, ozone inter-annual variability and trends were studied using the Trend-Run model as described above. The contribution and response of dynamical forcings to TCO variability are presented and discussed in Sect. 4.2. The aim of this study was to analyse the behaviour of each individual forcing contribution and to quantify the effect of its contribution on ozone variability in terms of TCO and mixing ratio profiles for the 15–30 km altitude range. The observed solar flux response to ozone over the selected altitude range is very weak (less than 1 %); the solar flux contribution to ozone vertical distribution is therefore not discussed. Ozone trends (for the observation period) as estimated by the model are presented (per site) in the final subsection. ## 4.1 Model assessment In order to quantify the fit of the regression model with original ozone data, a statistical coefficient R2 was used. The coefficient R2 is defined as the ratio of a regression sum of squares to the total sum of squares (Bègue et al., 2010) and it measures the proportion of the total variation in ozone as described by the model. When the regression model accounts for most of the observed variation in ozone time series, the value of R2 is close to unity. For the cases where the model shows little agreement with measured data, R2 decreases toward zero (Bègue et al., 2010; Toihir et al., 2014). Figure 5 shows the time evolution of total column ozone as simulated by the multi-regression model (black). The blue lines correspond to TCO measurements performed over the (a) equatorial, (b) tropical and (c) subtropical latitude bands. A good agreement between model and observations is apparent over the three regions and the best fit is observed for the extratropics. This is because the variability is usually influenced by the seasonal cycle which is well accounted for by the regression model (Eq. 3). The values obtained for the statistical coefficient R2 were 0.75, 0.71 and 0.91 for the equatorial, tropical and subtropical bands respectively. These results indicate that the model describes approximately 75, 71 and 91 % of TCO variability. This implies that the sum of the contributions of the annual cycle, semi-annual cycle, QBO, ENSO, solar flux and trend to TCO variability reached 75, 71 and 91 % for the equatorial, tropical and subtropical bands respectively. That represents how the model is able to reproduce most of the variability of the studied ozone time series. Statistical coefficients (R2) higher than 0.82 were highlighted by Toihir et al. (2014) over sites located at 30–40 S, while Bencherif et al. (2006) and Bègue et al. (2010) demonstrated that the Trend-Run model is able to describe approximately 80 % of the temperature variability observed over Durban (South Africa) and Reunion. Regarding vertical ozone distribution, profiles plotted in Fig. 4 were interpolated at a vertical resolution of 0.1 km which resulted in 150 altitude levels for the range between 15 and 30 km. The multi-regression model calculation was performed for each altitude level and profiles of the coefficient of determination R2 obtained at (a) equatorial, (b) tropical and (c) subtropical bands are shown in Fig. 6. The calculated R2 values were higher than 0.6, and this indicates that the input parameters account for more than 60 % of ozone variability in the 15–30 km altitude range. Figure 6Vertical profiles of R2 (determination coefficient) calculated by the Trend-Run model for the selected latitude range: (a) equatorial, (b) tropical and (c) subtropical regions. A study by Brunner et al. (2006) demonstrated that high values of R2 characterized a regime dominated by seasonal variability, while R2 values between 0.3 and 0.7 described cases where ozone variability was dominated by QBO. This is in agreement with results from the present study and confirms the capacity of the Trend-Run model to retrieve consistent ozone time series. As seen from Fig. 6, values of R2 greater than 0.8 were recorded at different altitude layers depending on the region, namely, in the 16.3–26.0 km range for the equatorial region, in the 17.3–22.2 km layer for the tropics and between 18.9 and 24.5 km for the extratropics. Furthermore, this analysis demonstrates that the noted altitude ranges are dominated by a seasonal variability which is expressed by an annual cycle function in the model. ## 4.2 TCO variability ### 4.2.1 Seasonal variability Figure 7 illustrates ozone climatology obtained by compilation of 15 years of data recorded between January 1998 and December 2012. Three regions are explored: (a) equatorial, (b) tropical and (c) subtropical. Over these selected regions, total ozone exhibited high values from July to November. A positive gradient was observed from May to the maximum annual peak in September (equatorial region) but occurred a month later in October for tropical and near-subtropical regions. The recorded positive gradient over the subtropics was the largest and this indicated a high seasonal variability in this region compared to tropical and equatorial zones. Low ozone levels were recorded during the austral summer/autumn period over the three regions. Ozone recorded in the equatorial region was high in March, April and May compared to the tropics. Two peaks were clearly observed for the equatorial region, and these highlight a semi-annual cycle with a maximum in September–October and a second maximum in March–May. Figure 7Seasonal variations of total ozone over three different regions: equatorial (a), tropical (b) and subtropical (c) regions. Error bars represent ±1σ. These results can be explained as follows: stratospheric ozone is formed through a photochemical reaction (Chapman, 1930) that requires a sufficient quantity of solar radiation. The equatorial region is therefore the primary site of ozone production (Coe and Webb, 2003). During the period close to equinox, solar radiation leads to an increase in ozone production over the equatorial region. During summer, ozone transport consists primarily of vertical upwelling movements which are confined to the low-latitude region. This results in less ozone being distributed to the subtropics. This effect is the main contributing factor to why a total ozone peak is observed in autumn over the equatorial region (Mzé et al., 2010). However, the semi-annual equinox process may not be the sole explanation for the maximum value recorded in the equatorial region during September spring equinox, because it is generalized over the three regions. High ozone levels recorded in winter/spring are due to transport and accumulation of ozone in the Southern Hemisphere as a result of Brewer–Dobson circulation on a regional (air mass transport from the tropics to subtropics) and global scale (from summer hemisphere to winter hemisphere) (Holton et al., 1995; Fioletov, 2008). Transport of ozone from the tropical to extratropical regions is the most dominant process during the winter period (Portafaix, 2003) and constitutes the principal reason for the observed annual maximum over the region 20–30 S. The decline of ozone levels during late spring and summer is explained by a decrease in ozone transport coupled with ozone photochemical loss (Fioletov, 2008). However, the observation of maximum ozone in September over the equatorial region but 1 month later over the subtropics may be explained by a delay of ozone transport between the two regions. As shown in Fig. 7, the curve of the seasonal distribution of TCO attributed to (b) the tropical region is below that of (a) the equatorial zone from January to September. While considering the process of formation and transport of ozone as described above, TCO annual records in tropical regions should be higher than that recorded over equatorial regions. However, it is important to note that both sites (Samoa and Fiji, in the 10–20 latitude range) are located in the Pacific Ocean. The low TCO quantity observed in the Pacific is due to a low tropospheric ozone levels over the region as a result of a zonal Wave-One observed on tropical tropospheric ozone (Thompson et al., 2003a and 2003b). Similar results were reported by Thompson et al. ( 2003a and 2003b) where low ozone levels over SHADOZ Pacific sites were observed with respect to African and Atlantic sites due to the zonal Wave-One. The contribution of seasonal cycles (annual and semi-annual oscillations) to ozone variability obtained from the regression analysis is presented in the first and second columns of Table 4. The calculated values show that except for Nairobi, the annual cycle constitutes the predominant mode of ozone variability over the studied sites and its influence is strongly observed over the subtropics. The contribution of annual oscillations to ozone variability exhibits a latitudinal signature, with its minimum and maximum at equatorial and subtropical zones respectively. The percentage contribution of annual oscillations to TCO variability decreases equatorward from Irene (65.96±3.93 %) to Nairobi (20.33±1.89 %). As explained in Sect. 3, the annual cycle is modeled by a sinusoidal function with maximum and minimum in winter/spring and autumn/summer. This kind of annual variation mode characterizes the ozone climatology of southern tropics and subtropics (Toihir et al., 2013, 2015a). The response of annual oscillations to ozone variability obtained for individual sites and reported in Table 5 is positive. This indicates that the modeled annual cycle function is in phase with the original ozone data. However, the amplitude of the annual cycle on total variance of ozone over the subtropics is the highest, and this indicates that ozone variance is sensitive to annual oscillation in the subtropics compared to tropics. The amplitude was evaluated at approximately 5.6 % by unit of the standardized annual function in subtropical sites (Reunion and Irene) and varied between 1 and 3 % from Fiji towards the Equator. Table 4Percentage of the contribution and corresponding SD of the annual cycle, semi-annual cycle, 11-year solar cycle, QBO and ENSO to total ozone variability for individual sites, as obtained by the Trend-Run regression model. The last column shows the corresponding value for the coefficient of determination R2. Table 5Response values of the chosen proxies (annual cycle, semi-annual cycle, solar flux, QBO and ENSO) to total ozone variability for individual sites as obtained by the Trend-Run model. The response is given in percent by unit of the normalized proxy. Results presented in Table 4 show that on average, 13.86±1.26 % of ozone variability can be explained by semi-annual oscillations over stations located at 5–10 S. However, the semi-annual pattern was not apparent over Nairobi compared to the rest of the equatorial sites. The predominant mode of ozone variability in this equatorial site was the QBO (20.48±1.92 %), followed by the annual oscillations (20.33±1.89 %). The semi-annual oscillation pattern of TCO was observed to be significant at low latitude, with its maximum contribution over Ascension Island. The response values associated with semi-annual oscillation to ozone variability are presented in column 2 of Table 5 and show that a maximum in amplitude over Ascension Island was observed. Both quantities (contribution and response) decreased gradually while moving away from the Ascension Island site towards the Equator or southward. This indicates that the semi-annual oscillations of ozone are weighted at approximately 8 of latitude and coincide with the location where the influence of equinox processes on ozone variability is the greatest. ### 4.2.2 QBO contribution The QBO constitutes the second most important parameter influencing ozone variability after seasonal oscillations. The QBO behaviour on ozone time series can be observed by removing the monthly climatological value from its monthly mean. In this investigation, the deseasonalized ozone signal was further subjected to 3-month smoothing in order to filter out smaller perturbations from intra-seasonal oscillations and to address the component due to ozone biennial oscillations. Figure 8 illustrates the deseasonalized ozone (blue dashed curve) time series (1998–2012) for equatorial and subtropical regions. These data are superimposed with the monthly mean zonal wind data at 30 hPa over Singapore (black curve). From Fig. 8 it can be seen that the predominant variability of deseasonalized monthly ozone data is an approximately 2-year cycle linked to the QBO and represented by the zonal wind data at 30 hPa. However, the equatorial and subtropical ozone signals seem to be opposite in phase. This indicates that if an excess of ozone is recorded over the equatorial region, the subtropical zone shows a trend illustrating a deficit with respect to the monthly climatological value and vice versa. The QBO change from the Equator to the subtropics is due to a secondary circulation having an upwelling branch in the subtropics and a subsidence branch in the tropics during the westerly phase of the QBO (Chehade et al., 2014). This secondary circulation is characterized by a deceleration or an acceleration of the Brewer–Dobson circulation (BDC) during the westerly or easterly phase of the QBO respectively. The deceleration of the BDC leads to an increase in ozone in the tropics, while the acceleration leads to a decrease in ozone in the tropics. Due to this circulation, the deseasonalized TCO data over the equatorial region are in phase with the QBO index. Positive ozone anomalies correspond to the QBO westerly phase and negative anomalies are linked to the QBO easterly phase. Similar results have been determined in previous studies (Randel and Wu, 2007; Butchart et al., 2003; Zou et al., 2000; Bourassa et al., 2014; Peres et al., 2017). Figure 8Deseasonalized time series of total ozone (blue line) for equatorial (0–10 S) and subtropical (20–30 S) regions calculated by subtracting the ozone monthly mean from the corresponding monthly climatological value. The black line is the time series in months of zonal wind recorded at 30 hPa over Singapore. The above process was explained by Peres et al. (2017) and may be outlined as follows: the descending westerly phases of the QBO are associated with a vertical circulation characterized by downward motion in the tropics and upward motion in the subtropics. This leads to a weakening of the normal speed of the Brewer–Dobson circulation. In this way the upward motion of air mass is slowed down and the tropopause height decreases. As the ozone mixing ratio increases with the increase in altitude in the lower stratosphere, ozone production can occur for a longer period than normal (Cordero et al., 2012). This mechanism leads to a positive column ozone anomaly at low latitudes and a negative anomaly in the subtropics. During the QBO descending easterly phase, ozone formed spends less time at low latitude due to the enhanced Brewer–Dobson circulation (Cordero et al., 2012). The newly created ozone is rapidly transported to the subtropics, resulting in a negative ozone anomaly at lower latitudes and a positive ozone anomaly in the extratropics. Butchart et al. (2003) explained that the equatorial ozone anomalies due to QBO forcing extend to 15–20 of latitude. In order to investigate the border between equatorial and subtropical QBO signals on ozone, the response of the QBO signal to TCO variability for individual sites was calculated based on the regression coefficient associated with the QBO on the Trend-Run model (Eq. 4). The response values are given in column 5 of Table 5. It is seen that the response of QBO to TCO variability by unit of normalized QBO signal is positive when the QBO is in phase with the ozone signal and negative for the reverse case. In this study a positive response (of decreasing magnitude) is obtained with the decrease in latitude moving from Samoa (14.13 S) to Nairobi (1.27 S). Conversely the responses obtained are negative at Fiji (18.13 S), Reunion (21.06 S) and Irene (25.90 S). These results indicate that the border between the equatorial and subtropical QBO-ozone signature is found at around 15 in latitude. Similar results were reported by Chehade et al. (2014) by calculating the coefficients of regression associated with the influence of the QBO on ozone variability. The Chehade et al. (2014) study reported positive and negative regression coefficients between 0 and 15 S and from 15 S towards the pole respectively. In this work, positive ozone anomalies with amplitude varying between 7.5 and 13.9 DU were recorded over the equatorial sites during the zonal wind westerly phase, while the negative anomalies observed during the easterly phase oscillated between 13.3 and 2.80 DU. These results indicate that inter-annual oscillations of TCO over the equatorial regions have maximum amplitude varying within ±14 DU during the study period (1998–2012). This is in agreement with the results of Butchart et al. (2003). For 1980 to 2000 they obtained a deseasonalized ozone signal which varied within ±14 DU over the Equator. It is worth noting that the maximum amplitude of ozone anomalies observed in the subtropics is lower (within ±11 DU) than the equatorial region (±14 DU). These amplitude values indicate that the QBO modulation on inter-annual variability of ozone is higher over the equatorial region in comparison to the extratropics. Values reported in Table 4 show a clearly decreasing QBO contribution poleward, i.e. from Nairobi (20.48±1.92 %) in the equatorial zone to Irene (3.60±1.07 %) in the subtropics. ### 4.2.3 ENSO contribution Column 6 of Table 4 presents the percentage of ENSO contributions to inter-annual ozone variability for individual sites. It is clear that the ENSO parameter does not exert much influence on ozone variability over the subtropical sites (Reunion and Irene), where its contribution to TCO variability is assessed to be less than 1 %. However, the ENSO contribution is more pronounced over tropical and low-latitude sites located between 19 S and the Equator. In this latitude band, the ENSO contributions observed at Fiji, Samoa, Ascension Island and Java are high compared to Natal and Nairobi. An average ENSO contribution of 9.40±0.65 % to total ozone variability over Fiji, Samoa, Ascension Island and Java is observed, while a corresponding value of 5.73±0.75 % for Natal and Nairobi is seen (see Table 4). These results indicate that the ENSO influence on total ozone variability is high over the tropics compared to that in the equatorial zone and subtropics. It has been reported by Randel et al. (2009) that ENSO originates in the tropics and is linked to coupled atmosphere–ocean dynamics. This factor may be the main reason for the observed high ENSO contribution over sites located in the tropics compared to low-latitude and subtropical sites. Zerefos et al. (1992) removed the QBO, seasonal and solar cycles from the ozone signal at Samoa and obtained a good correlation between ENSO and ozone signal. They mentioned a possible ENSO–ozone relationship beyond the tropical region only during very large ENSO events (e.g. 1982–1983, 1997). In this study, the low estimated ENSO contribution (less than 1 %) for the subtropical region may also be explained by the fact that there were few large ENSO events recorded during the investigated period (1998–2012). The tropical sites located in the Pacific Ocean (Samoa, Fiji and Java) were more influenced by ENSO when compared to tropical and equatorial sites (Ascension Island, Natal and Nairobi) due to the high ENSO activity usually observed in the Pacific Ocean (Randel and Thompson, 2011; Chandra et al., 1998, 2007; Logan et al., 2008; Ziemke and Chandra, 2003; Ziemke et al., 2010). In addition, the Ascension Island ENSO contribution was higher compared to those observed at Natal and Nairobi. As ENSO is a coupling ocean–atmosphere event generated in the Pacific Ocean (Ziemke and Chandra, 2003; Rieder et al., 2013), the low ENSO contribution recorded over Natal and Nairobi compared to Ascension Island can be explained by their continental location. As Ascension Island is located in the Atlantic Ocean, the high ENSO contribution observed at this site is probably due to a Pacific–Atlantic Ocean connection. The ENSO response to ozone variance is assessed and shown in the last column of Table 5. The aim of this work is to define the mean behaviour of ozone variance for individual sites during ENSO events. It is worth noting that the mean ENSO influence is observed on tropospheric ozone (Randel and Thompson, 2011; Ziemke and Chandra, 2003). However, due to weak variability in stratospheric ozone over the tropics (Ziemke et al., 1998) during periods of normal conditions, tropospheric ozone changes were shown to affect the stratospheric ozone and total column ozone variability over the tropics during ENSO events (Rieder et al., 2013). As the MEI is characterized by positive values during El Niño, a positive ENSO response indicates an increase in total column ozone (TCO) and a negative response indicates a decrease in TCO. The ENSO response to ozone variability over subtropical sites (Reunion and Irene) is positive, while it is generally negative over the tropics (except over Java and Nairobi). These results are in good agreement with those reported by Chehade et al. (2014) which are obtained using a regression analysis model. Through their study they obtained negative (positive) ENSO regression coefficients indicating a negative (positive) ENSO response to ozone variability over the tropics (extratropics). It has been mentioned in several papers (Rieder et al., 2013; Randel et al. 2009; Randel and Thompson, 2011; Frossard et al., 2013; Chehade et al., 2014) that a negative ENSO response to ozone variability in the tropics is linked to enhanced transport of an ozone-rich air mass from the tropics to the extratropics due to strengthening of the Brewer–Dobson circulation in the stratosphere during ENSO warm events. As reported by Rieder et al. (2013), ENSO events are associated with more frequent stratospheric warming, an increase in tropopause height and a decrease in stratospheric ozone in the tropics. By comparison, in the subtropics, the tropopause height decreases and stratospheric ozone increases. This effect could be the reason for the observed ENSO positive response over Irene and Reunion (subtropics). The ENSO warm events produce suppressed convective movements over the western Pacific, leading to a positive anomaly of ozone in this region, while the air mass convection is enhanced over the eastern Pacific that leads to a reduction of ozone (Ziemke and Chandra, 2003). For the period 1970–2001, Ziemke and Chandra (2003) obtained a positive El Niño response corresponding to an average peak of positive ozone anomaly evaluated at 5 DU over the Indonesia area. Furthermore, they found a negative ozone anomaly in the eastern Pacific, the location of Fiji and Samoa. According to Ziemke and Chandra, (2003), this could be the main reason for the observed positive ENSO response at Java in the western Pacific and negative response over Samoa and Fiji in the eastern Pacific. The connection between the western Pacific and the Indian Ocean could be among the reasons for the observed positive ENSO response to ozone variability at Nairobi in the eastern African and Reunion in the western Indian Ocean region. ### 4.2.4 Solar flux contribution Variation in total ozone concentration also depends on solar flux intensity over the tropics and subtropics. Figure 9 illustrates the variation in annual total ozone anomaly calculated between 1998 and 2012 over the three regions (bottom panel) and the annual 10.7 cm solar radio flux variation during the same period (top panel). Inspection of Fig. 9 illustrates the effect of the 11-year solar cycle on inter-annual total ozone variations. Negative ozone anomalies are observed during periods of low sunspot intensity, thereby confirming the dependence of ozone production on incident solar radiation flux. The converse is also true; that is, high annual total ozone levels are associated with periods of high sunspot intensity. The results presented here are in good agreement with Soukharev and Hood (2006). The latter obtained negative (positive) monthly mean ozone anomalies during periods with low (high) Mg II solar UV intensity. The dependence of annual ozone levels on annual solar radiation is also highlighted by Efstathiou and Varotsos (2013). In this investigation, the high levels of TCO were observed over the tropics when solar activity was at a maximum (2001) and compared to values recorded during a minimum in solar activity in 2008. This illustrated the impact of the solar cycle on global ozone concentrations. In the work presented here, considering the year with solar maximum (2001) to the year with minimum solar intensity, a variation in ozone levels was observed corresponding to approximately 1.05, 1.52, and 1.60 % for the (a) equatorial, (b) tropical and (c) extratropical regions respectively. It is expected that the observed percentage change in ozone levels is directly related to solar flux activity. A study by Zerefos et al. (1997) confirmed that the solar flux component in TCO between 1964 and 1994 was approximately 1–2 % over decadal timescales. It can therefore be concluded from the results presented here, together with those of Zerefos et al. (1997), that the solar flux contribution to ozone variability did not vary significantly during the past 6 decades. Figure 9(a) Annual mean of 11-year solar flux recorded from 1998 to 2012 and (b) the annual TCO anomaly recorded for the same period in equatorial, tropical and subtropical regions. As the solar flux index is one of the input parameters in the regression model, the contribution and response of the 11-year solar cycle to total ozone variability were assessed. The effect of changes in solar flux on ozone levels is presented in the fourth column of Table 5. The obtained responses are always positive, indicating that the solar flux index is in phase with total ozone time evolution as reported in the WMO (2014). The increase in ozone occurs when the sunspot intensity increases and vice versa. The average magnitude of the solar flux response to ozone variability is about 1.57 % by unit of solar flux index. The contribution of solar flux to total ozone variability over the study region varies by between approximately 4.38 and 7.81 %. The contribution of the solar cycle is high compared to the 3 % reported by the WMO (2010, 2014) on the global scale. This is probably due to (1) the length of the data records (less than two solar cycles), (2) the time period under investigation (1998–2012) and (3) the studied region (from equatorial to around 40 S). However, the contribution values obtained exhibit a minimum at Reunion in the subtropics and a maximum at Ascension Island in the lower-latitude region. These results indicate a high solar flux influence over the low-latitude region in comparison with the subtropics. The contribution of solar flux to total ozone variability decreases gradually by moving away from Ascension Island equatorward or southward. This solar flux contribution pattern is similar to that observed in semi-annual oscillations (see Sect. 4.2.1). From the results presented in this study it can be inferred that semi-annual variations are modulated by solar activity over the tropics and subtropics and that both semi-annual and 11-year solar forcings control ozone distributions. ## 4.3 Height profile ozone variability The main objective of this section is to provide additional details regarding the contribution of proxies to ozone variability for different altitude levels from 15 to 30 km. This exercise is based on vertical distribution of ozone concentration as presented in Fig. 4. Here the ozone profiles are interpolated with 0.1 km vertical resolution giving 150 altitude levels in the 15–30 km altitude range. The Trend-Run model is applied to each altitude level. ### 4.3.1 Seasonal contribution to ozone profile variability The contributions of annual and semi-annual oscillations to ozone variability (15 to 30 km) are shown in Fig. 10. Figure 10 reveals that seasonal cycles are the most dominant forcings to ozone variability in the lower stratosphere. The contribution of annual oscillation (AO) to ozone variability is highlighted over the three studied regions and accounts for more than 40 % in the UT–LS (upper troposphere–lower stratosphere). AO maximum amplitudes in equatorial and tropical regions are found around the tropical tropopause layer (TTL) below 20 km and around 22.5 km in the subtropics. These results are in good agreement with recent findings. Gebhardt et al. (2014) showed that in the lower stratosphere (21 km), ozone variability is dominated by AO in the tropics (20 N–20 S). Furthermore, Eckert et al. (2014) explained that vertical motion in the TTL had a significant impact on ozone variance and that seasonal variations contributed more than 50 % to ozone variability in this layer. A strong annual cycle signature in the UT–LS has also been reported by Bègue et al. (2010). The important contribution of the annual cycle in the UT–LS may be due to the STE (stratosphere–troposphere exchange) processes which occur seasonally in the tropics. These exchanges are linked to the upwelling air mass through the tropopause in summer and the submersion of stratospheric air mass to the troposphere during winter. These air mass exchanges affect the seasonal budget of ozone and temperature from equatorial to middle latitude. As seen in Fig. 10, annual cycle contributions higher than 40 % are found from 15 to 20 km over the equatorial region. However, the annual cycle contributions higher than 40 % observed over the tropical region are found from 17.5 to 22 km. In addition, the maximum annual cycle contribution for the equatorial region is observed at 18.5 km, whilst in the tropics it occurs at 19.5 km. These observations support the existence of upward propagation of the AOs of ozone below 25 km and the amplitude of these AOs increases with the increase in latitude poleward. This may explain the high annual cycle contribution observed in the 15–24.7 km altitude range in the subtropics. The presence of an annual signature in ozone temporal evolution in this wide altitude band (15–24.7 km) in the subtropics is inconsistent with the strong annual variability observed in TCO, as discussed in the previous subsection. Figure 10Height profile in % of the contribution of the annual cycle (a1–c1) and the semi-annual cycle (a2–c2) to ozone variability as calculated by the Trend-Run model over the equatorial (a1, a2), tropical (b1, b2) and subtropical (c1, c2) regions. SDs associated with contributions are presented in grey dotted lines. It is worth noting that the seasonal cycles of ozone observed at altitudes below 25 km are linked to dynamical processes, while above an altitude of 27 km, seasonal cycles are modulated by ozone photochemical processes. Contributions of the annual forcing of greater than 10 % are observed at altitudes above 27 km. Here the contribution part of annual oscillation increases with altitude, especially over the tropical and subtropical regions. These results support the existence of an annual cycle signature on ozone temporal evolution over altitudes above 30 km in the tropical and subtropical regions. Eckert et al. (2014) found that ozone variation due to AO was greater than 10 % above 27 km in the 10–30 S latitude band. However, this amplitude decreases above 35 km, where ozone variability is strongly controlled by semi-annual oscillation (SAO). Furthermore, the maximum amplitude of the ozone SAO signal observed by Eckert et al. (2014) was centered slightly above 30 km over the tropics. Mze et al. (2010) observed a strong semi-annual cycle in equatorial ozone climatology between 27 and 36 km, with a maximum peak at 31 km, and Gebhardt et al. (2014) observed ozone variability dominated by SAO in the middle (35 km) and upper tropical stratosphere (44 km) in the tropics (20 N–20 S). The (SAO) contribution to ozone variability is highlighted in the present work for altitudes higher than 27 km for the equatorial and tropical regions. Above 27 km, the SAO contribution accounts for more than 10 % of total ozone variability over the equatorial region, while this effect is reduced to less than 10 % for the tropics. This confirms the high contribution of SAO to ozone variability at low latitudes with respect to other regions as discussed in Sect. 4.1.1. As supported by Eckert et al. (2014), beyond the tropics the SAO amplitude decreases gradually to near zero. As reported in previous studies, the SAO is linked to change in the zonal wind regime at the equatorial stratopause, where the maximum component appears during solstice (when easterly) and equinox (when westerly) (Belmont, 1975; Hirota, 1978; Delisi and Dunkerton, 1988). This mechanism leads to temperature anomalies corresponding to 2–4 K in the upper stratosphere (Nastrom and Belmont, 1975), thereby driving a change in the rate of ozone production and loss (Maeda, 1984) during the solstice and equinox periods. As demonstrated in Sect. 4.2.1, the equinox period is characterized by maximum peaks of TCO production over the equatorial region, while the solstice corresponds to minimum ozone levels (or ozone loss) over equatorial regions. ### 4.3.2 QBO contribution to ozone profile variability QBO contributions to ozone profile variability between 15 and 30 km are presented in Fig. 11 for the three regions, namely (a1) equatorial, (b1) tropical and (c1) subtropical. A strong contribution of the QBO to ozone variability is observed over the 20–28 km altitude range for the equatorial region. Here the QBO is the most dominant mode and accounts for more than 30 % of ozone variability. These results are in agreement with previous work in which a strong signature of the QBO on inter-annual variability of ozone with large amplitudes over the tropics at altitudes of approximately 20–27 km has been reported (Randel and Thompson, 2011; Gebhardt et al., 2014; Eckert et al., 2014). Figure 11a1 shows two strong peaks at 60 % corresponding to altitudes of 21.5 and 25 km. The QBO contribution is important and does not change much over the altitude range 24 to 26.5 km, indicating that the maximum amplitude of the QBO signature occurs in this altitude range, where the degree of QBO influence on ozone variability is approximately invariant. Fadnavis and Beig (2009) found the QBO maximum over tropics at approximately 26 km, while Eckert et al. (2014) found this maximum at 25 km. The QBO signal on ozone variability is linked to the downward propagation of zonal wind throughout the time. This process leads to a positive (negative) ozone anomaly when in the westerly (easterly) mode with a cycle of around 2 years (Randel and Thompson, 2011; Lee et al., 2010; Butchart et al., 2003). Note that the maximum contributions of the QBO over the tropical and subtropical regions (Fig. 11b1 and c1) are less than 12 %. These results confirm the latitudinal signature of the QBO which is expressed by a decrease in its effect on ozone variability poleward. The inter-annual ozone anomaly linked to the QBO time evolution can be positive or negative depending on the altitude range for a given period due to the downward propagation pattern of the QBO with time (Randel and Thompson, 2011). The responses of the QBO index used are presented in Fig. 11 as (a2) equatorial, (b2) tropical and (c2) subtropical regions. Over the equatorial region, the QBO index profile exhibits positive values below 23 km and negative values above. These results indicate a strong contribution of the QBO westerly regime to ozone variability for equatorial regions below 23 km during the studied period (1998–2012). In contrast, the easterly regime had more influence on variability of ozone above altitudes of 23 km. The opposite case is observed in the subtropics, where the QBO index profile exhibits positive values for altitudes between 18 and 23 km and negative values between altitudes of 23 to 27.5 km. Similar results have been reported by Bourassa et al. (2014). The response amplitude obtained in this work over the subtropics varies within ±5 %, whilst it is at ±7 % (by unit of the normalized QBO index) over the equatorial region. These results reaffirm the key role of the QBO in ozone variability highlighted in equatorial regions in contrast to the subtropics. Figure 11Height profile in % of the QBO contribution of (a1–c1) and response by unit of the QBO index (a2–c2) as calculated by the Trend-Run model over the equatorial (a1, a2), tropical (b1, b2) and subtropical (c1, c2) regions. SDs associated with contributions are presented in grey dotted lines. ### 4.3.3 ENSO contribution to ozone profile variability ENSO contributions to ozone profile variability over the 15–30 km altitude range are presented in Fig. 12 for the three regions (a1) equatorial, (b1) tropical and (c1) subtropical. These calculations show that ENSO events weakly affect subtropical ozone levels. In contrast, the ENSO contribution and its associated response to ozone variability appear to be important below an altitude of 25 km at tropical latitudes. These results are in good agreement with the study by Sioris et al. (2014) in which a statistically significant ENSO contribution was reported at an altitude of 18.5–24.5 km in the tropics. Such results indicate that ENSO influence on ozone variability is essentially focused on the troposphere and lower stratosphere. ENSO contribution to the lower stratospheric ozone is highlighted by the 20–25 km altitude band with peaks toward 15 and 13 % over the tropical (at 23 km) and equatorial (at 21 km) regions respectively. The response linked to this contribution over the equatorial region oscillates with amplitude, varying between 8 and 4 % (Fig. 12, curve a2). Here the ENSO response values are negative below an altitude of 23 km and positive in the 23–26 km altitude range, indicating that the multivariate ENSO index is in phase with ozone time evolution above 23 km and in opposite phase below 23 km. As reported in previous studies (Ziemke and Chandra, 2003; Rieder et al., 2013), ENSO events contribute to the variation in tropopause height associated with decrease/increase in TCO due to the enhancing/suppressing of tropical convection. The results obtained in the equatorial region indicate that the ENSO effect, associated with enhanced convection, generally affects the lower part of the stratosphere. This leads to a decrease in ozone levels below 23 km, while the suppressed convection present generally results in a positive response to ozone variance above 23 km. Figure 12Height profile in % of the contribution of ENSO (a1–c1) and response by unit of the ENSO index (a2–c2) as calculated by the Trend-Run model over the equatorial (a1, a2), tropical (b1, b2) and subtropical (c1, c2) regions. SDs associated with contributions are presented in grey dotted lines. However, the amplitude obtained for the negative ENSO response is the largest. These results suggest that ozone variability linked to ENSO events is more sensitive to the enhanced equatorial convection in the UT–LS. In a recent study, similar results were reported by Randel and Thompson (2011), in which they observed a large negative change in ozone variance due to enhanced Brewer–Dobson circulation over the tropics associated with ENSO variability. In addition, the obtained ENSO response over the tropical region (Fig. 12b2) is negative, indicating a decrease in ozone due to ENSO events occurring during the study period. From the troposphere to approximately 20 km, the ENSO signal exhibits an important contribution and response to ozone variability over the tropics as reported in previous published works (Bourassa et al., 2014; Sioris et al., 2014; Randel and Thompson, 2011). However, the response obtained has a larger amplitude (maximum of 38 % at 16.5 km) than those reported by the above-mentioned papers due to the location of the Fiji and Samoa stations (the two sites that represent the tropical region in this work). As mentioned above, Fiji and Samoa are located in the eastern Pacific, a region where ENSO events are significant. Here the ENSO contribution to total ozone variability is observed to be greater than 10 % below 18.7 km. The negative ENSO response associated with this contribution is explained by an enhanced tropical upwelling during ENSO events which led to a decrease in ozone levels in the lower stratosphere of the eastern Pacific Ocean region as reported by previous studies (Randel and Thompson, 2011; Randel et al., 2009; Calvo et al., 2010). ## 4.4 The trend estimates ### 4.4.1 Total column ozone trends The trend analysis of TCO was performed for each site and results presented in Fig. 13. The TCO trends are assessed based on the Trend-Run model and expressed in percentage per decade. The obtained trend values are positive, suggesting an increase in TCO during the study period. However, the mean values of TCO trends obtained from the Samoa site (14.13 S) equatorward are lower than 1 %, while they are higher than 1.5 % for Fiji (18.13 S), Reunion (21.06 S) and Irene (25.90 S). These results illustrate that the increase in TCO in the subtropics is greater than in the tropics. Figure 14 summarizes the trend evolution over the three latitudinal bands. An increase in the trend with latitude southward is observed. The average trends (in percentage per decade) are $+\mathrm{0.74}±\mathrm{0.6}$, $+\mathrm{1.55}±\mathrm{0.4}$ and $+\mathrm{1.74}±\mathrm{0.40}$ (±1σ) over the equatorial, tropical and subtropical regions respectively. These TCO trend results are consistent with the WMO (2014), where a positive trend of approximately 1±1.7 (±2σ) was reported at 60 N–60 S for the period 2000–2013. These positive trends are probably linked to the decline of effective equivalent stratospheric chlorine (EESC) over the globe as supported by previous studies (Yang et al., 2006; Anderson et al., 2000; Waugh et al., 2001; WMO 2010). However, compared with the tropics and subtropics, the delay in ozone improvement observed in the equatorial region is probably due to the tropical strengthening of the Brewer–Dobson circulation (WMO 2014; Randel and Thompson, 2011). Figure 13Time evolution of monthly total ozone values (blue) observed at each site. The black lines represent the time evolution of the TCO obtained by the Trend-Run model, the blue lines show observation data, and the straight black line illustrates the obtained decadal trend. Figure 14The same as Fig. 13 but per latitudinal region: equatorial (a), tropical (b) and subtropical (c). It should be noted that approximately 10 % of ozone is tropospheric and is produced as a result of chemical reactions between species such as nitrogen oxide (NOx), carbon monoxide (CO) or volatile organic compounds (VOCs). In the context of climate change due to anthropogenic pollutant emissions and in spite of the efforts by the international community to reduce GHG emissions, pollution has continued to increase in the Southern Hemisphere, leading to a systematic increase in tropospheric ozone. Thompson et al. (2014) assumed that growth in ozone precursors like NOx and VOC may account for the characteristic free tropospheric ozone increase, especially in wintertime. The observed positive trend in TCO time series is therefore probably due also to an increase in and long-range transport of pollutants (mainly from industrial and biomass burning activity) in the free troposphere of the southern tropics and subtropics, as suggested by previous studies (Diab et al., 2004; Thompson et al., 2014; Clain et al., 2009). Thompson et al. (2014) highlighted significant increases throughout the free troposphere, 20–30 % decade−1 over Irene and up to 50 % decade−1 over Reunion in the southern subtropical region. Furthermore, Heue et al. (2016) showed that the tropical tropospheric ozone trend is 0.7±0.12 DU (approximately 3.5 %) decade−1 between 1995 and 2015. There results show that there is an improvement in ozone from the ground to the middle atmosphere in the studied regions. Tropospheric ozone affects total column ozone trends; however, the contribution is not sufficient to modify the TCO trend compared to stratospheric ozone, which represents 90 % of the total ozone present. ### 4.4.2 Vertical distribution of the trends In this investigation, TCO analysis indicated a positive trend over the study region. However, a trend investigation in terms of vertical ozone distribution is necessary in order to understand trend variation through different altitude levels. Equatorial, tropical and subtropical ozone trend profiles estimated by the Trend-Run model are presented in Fig. 15, panels (a), (b) and (c) respectively. Considering the temporal coverage of Irene ozonesonde data (1998–2008 and some profiles recorded in 2012), the Irene and Reunion ozone profiles were separated for the sake of trend analysis. Figure 15c1 shows the ozone trend profile for Reunion, while that for Irene (January 1998 to December 2008) is shown in panel c2. Overall, the ozone trends obtained are negative in the upper troposphere and positive for altitudes higher than 22 km. This indicates an improvement in stratospheric ozone. For the equatorial region, the trend profile shows a positive gradient from 15 km to the tropopause (approximately 18 km), followed by a maximum positive ozone trend in the 18–22 km layer (about +2 %). A negative trend is seen between 22 and 25 km and a zero trend for heights above 25 km. The tropical trend evolution below 22 km is similar to the trend observed over Reunion (Fig. 15c1), which is marked by a negative peak around 19 km. Such a negative peak is probably a characteristic of the tropical trend and highlighted at Reunion due to the proximity of this station to the tropical zone. Figure 15Vertical profiles of ozone decadal trends derived by the Trend-Run model from 15 to 30 km at the Equator (a), tropics (b), Reunion (c1) and Irene (c2). Irene and Reunion are separated for this present case due to the lack of ozone profiles at the Irene station from January 2008 to October 2012. The Irene trend profile is derived based on ozone profiles recorded from January 1998 to December 2007 (10 years). The results in trend estimates over the equatorial region are similar to previous studies based on a combination of GOMOS and SAGE II data recorded between 1984 and 2011 performed by Kyrölä et al. (2013). This work showed an apparent improvement in ozone trends onwards from 1997. The recorded trend (1997–2011) in the 20–30 km altitude range is consistent with results obtained in the present study and can be summarized as follows: a positive trend of approximately 2 % in the altitude range 19–21 km and approximately 0 % between altitudes 21 and 30 km. A trend varying between 0 and 1 % was also observed by Randel and Thompson (2011) in an altitude range of 23 to 35 km by averaging SHADOZ and SAGE II ozone profiles recorded between 1984 and 2009 for latitudes 20 N–20 S. Furthermore, Randel and Thompson (2011) observed a negative peak at 19 km, similar to what was observed in this study over Reunion and the tropical region. This negative peak is explained as resulting from a systematic increased tropical lower stratospheric upwelling. As reported by the WMO (2014), the increase in tropical upwelling is associated with a strengthening of the Brewer–Dobson circulation caused by GHG-induced climate change. Furthermore, Lamarque and Solomon (2010) associated the declining trend in ozone levels in the lower tropical stratosphere with an increase in carbon dioxide and sea surface temperature. They also demonstrated that a decrease in ozone in the upper stratosphere could be strongly linked to an increase in halogen compounds at high altitudes. The results obtained in this work indicate that the positive trends observed over Reunion and Irene from TCO analyses are probably due to an increase in ozone levels in the stratosphere, which is associated with a decrease in halogen compounds and EESC at high altitudes. Declining EESC levels in the subtropical region constitutes the main reason for ozone increase as a result of the Montreal Protocol and its amendments (Yang et al., 2006; Anderson et al., 2000; Reinsel, 2002; WMO, 2010, 2014). The positive trend of 2 % in ozone levels recorded over the equatorial region in the 18–22 km altitude range cannot be explained by the decline of EESC compounds in the stratosphere. Instead, this trend could rather be linked to an increase in NOx (NO+NO2) in this altitude range (Gebhardt et al., 2014; Nevison et al., 1999). Furthermore, Gebhardt et al. (2014) obtained a positive ozone trend at altitudes higher than 18 km and the variation pattern observed is similar to that obtained in our study up to an altitude of approximately 23 km. The investigation of Gebhardt et al. (2014) was based on SCIAMACHY satellite observations (2002–2012). They associated the observed positive trend at 18–22 km with an increase in NOx concentration in the lower stratosphere. The idea that NOx levels may have a direct effect on stratospheric ozone variability is not new and was first suggested by Nevison et al. (1999). In this study they used a model in order to identify the NOx contribution to ozone variability at different altitudes in the stratosphere. Through these calculations it was found that the increase in NOx compounds in the lower stratosphere leads to an increase in ozone levels at this altitude. It is important to note that NOx can have a buffering effect on the Clx and HOx ozone-destruction cycles in the tropical lower stratosphere as explained by Nevison et al. (1999). 5 Conclusions This work describes and discusses the variability and associated trends in ozone measurements recorded between January 1998 and December 2012 over eight southern tropical and subtropical sites. Total ozone products from different instruments were presented and a very good agreement was found in products recorded by different instruments at the same site. This confirmed the good quality of products and the validity of combining these products in order to create a long-term and homogenous TCO dataset for the study of ozone variability and long-term trends over the southern tropics and subtropics. SHADOZ data, used for the study of vertical ozone distribution, were found to be good quality according to Thompson et al. (2003a, b). The analysis of the contribution and response of some parameters to total ozone variance was achieved through the use of a multi-regression model called Trend-Run. This model is able to describe 71–91 % of ozone variability influenced by seasonal variation of climate and by dynamic parameters such as QBO, ENSO and solar flux. The obtained results were found to be in good agreement with recent findings and can be summarized as follows. • Ozone variability over the study region is dominated by annual oscillation (AO) which strongly affects ozone variance in the UT–LS as a result of seasonal troposphere–stratosphere exchanges. The amplitude of ozone annual oscillations is high in the subtropics and decreases with latitude equatorward. In contrast, the ozone SAO is more apparent and contributes significantly above 27 km, with its maximum influence at the lower latitudes (around 8 S), where its amplitude decreases with movement toward the Equator or subtropics. • The QBO signal constitutes the second most important parameter in terms of effect on ozone variability in the tropics after the seasonal oscillation. QBO heavily affects ozone variance in 20–28 km of the altitude range, with its maximum amplitude in the equatorial region. The pattern of the QBO response to ozone variability in the equatorial region is out of phase with that of the subtropics. The border between equatorial and subtropical patterns is found at around 15 in latitude. • The ENSO contribution over the subtropics is less than 1 %. In contrast, an important contribution of ENSO to ozone variance is highlighted in the tropics, below 25 km with its maximum amplitude in the Pacific area. The tropical ENSO response is basically negative and was explained in previous work (Randel and Thompson, 2011; Sioris et al., 2014) as resulting from an enhancement of tropical convection leading to ozone decrease during warm ENSO events. • Solar flux and total ozone are in phase. Increase in ozone levels occurs when sunspot intensity increases and conversely periods of low sunspot activity correspond to periods of low ozone production. The maximum solar flux contribution is at the tropical latitudes. The mean contribution of solar flux to total ozone variability over the studied region is high (6.03±0.84 %) compared to the 3 % reported globally by the WMO (2010, 2014). This is probably due to the region selected for this study (tropics and subtropics), the length of the data records (less than two solar cycles) and the time period under investigation in this work (1998–2012). The regression model is also used to quantify ozone trends over the selected regions. Results obtained exhibit an upward trend of TCO during the period of study. The trend values were in good agreement with the WMO (2014) report (1±1.7 (2σ) at 60 N–60 S for the period 2000–2013) and exhibited an increase in ozone with increase in latitude from the Equator to the subtropics. The results of vertical profile analysis illustrated a positive ozone trend from 22 km upward and negative values in the upper troposphere, indicating that the ozone recovery observed in tropical and subtropical regions occurs in the stratosphere. It has been explained in recent studies (Sioris et al., 2014; Bourassa et al., 2014; Randel and Thompson et al., 2011) that the delay in ozone recovery at upper tropospheric and lower stratospheric levels was partly associated with a tropical enhancement of the Brewer–Dobson circulation over the tropics, while ozone recovery observed from an altitude of 22 km and upward was probably linked to declining levels of stratospheric chlorine and bromine compounds in the atmosphere. A further study continuing from this work would involve the inclusion of Brewer–Dobson and EESC indexes in the model not only to quantify the sources of observed trends, but also to improve the model quality. Author contributions Author contributions. AMT was the project leader; TP was the supervisor of the project; VS and HB participated in interpretation of the results and the review of the manuscript; AP and NB contributed to data analysis and the review of the manuscript. Competing interests Competing interests. The authors declare that they have no conflict of interest. Data availability Data availability. The data used in the present work are available and publicly accessible from different sites: Dobson and SAOZ TCO data, available at https://woudc.org/data/explore.php; TOMS TCO data, available at https://acdisc.gesdisc.eosdis.nasa.gov/opendap/ EarthProbe_TOMS_Level3/TOMSEPL3.008/contents.html; OMI data, available at https://gs614-avdc1-pz.gsfc.nasa.gov/pub/data/satellite/Aura/OMI/V03/L2OVP/OMTO3/; SHADOZ ozonesonde data, available at https://tropo.gsfc.nasa.gov/shadoz/Archive.html; ENSO, solar, and QBO flux indexes, available at https://www.esrl.noaa.gov/psd/data/climateindices/list/. Special issue statement Special issue statement. Acknowledgements Acknowledgements. The LACy (Laboratoire de l'Atmosphère et des Cyclones) is supported by the INSU (Institut National des Sciences de l'Univers), a CNRS institute, and by the Regional Council of Reunion (Conseil Regional de La Réunion). This present work is supported by the RAMI project, a regional doctoral school in the Indian Ocean zone, under the “Horizons Francophones” programme of the AUF (Agence Universitaire de la Francophonie) and the GDRI-ARSAIO (Atmospheric Research in Southern Africa and the Indian Ocean), a French–South African cooperative programme network supported by the French Centre National de la Recherche Scientifique (CNRS) and the South African National Research Foundation (NRF). The first author (Abdoulwahab Mohamed Toihir) acknowledges the Indian Ocean Bureau of AUF and the University of KwaZulu Natal for travel and hosting under invited student exchange in the above NRF-CNRS bilateral research project (UID 68668). The authors also thank Barbara Lynn Duigan (NASSP-UKZN) for improving the readability of the manuscript. The authors are thankful to agencies supporting NDACC activities: INSU/CNRS, CNES as well as the Canada WOUDC team, which is under the auspices of the WMO, the SHADOZ network, and the OMI and TOMS programmes, for providing access to data via their websites. Edited by: Petr Pisoft Reviewed by: Lucas Vaz Peres and two anonymous referees References Anderson, J., Russell III, J. M., Solomon, S., and Deaver, L. E.: Halogen occultation experiment confirmation of stratospheric chlorine decreases in accordance with the Montreal Protocol, J. Geophys. Res., 105, 4483–4490, 2000. Antón, M., Loyola, D., Clerbaux, C., López, M., Vilaplana, J. M., Bañón, M., Hadji-Lazaro, J., Valks, P., Hao, N., Zimmer, W., Coheur, P. 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Sci., 17, 562–568, 2000.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 14, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.870343804359436, "perplexity": 4499.0834286403715}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-05/segments/1579251796127.92/warc/CC-MAIN-20200129102701-20200129132701-00077.warc.gz"}
https://eprint.iacr.org/2005/043	### An Efficient Solution to The Millionaires' Problem Based on Homomorphic Encryption Hsiao-Ying Lin and Wen-Guey Tzeng ##### Abstract We proposed a two-round protocol for solving the Millionaires' Problem in the setting of semi-honest parties. Our protocol uses either multiplicative or additive homomorphic encryptions. Previously proposed protocols used additive or XOR homomorphic encryption schemes only. The computation and communication costs of our protocol are in the same asymptotic order as those of the other efficient protocols. Nevertheless, since multiplicative homomorphic encryption scheme is more efficient than an additive one practically, our construction saves computation time and communication bandwidth in practicality. Available format(s) Publication info Published elsewhere. This work appears in ACNS 2005. Keywords secure computationthe greater than problemthe socialist millionaires' problemhomomorphic encryption Contact author(s) lrain cis92g @ nctu edu tw History 2006-02-21: revised See all versions Short URL https://ia.cr/2005/043 CC BY BibTeX @misc{cryptoeprint:2005/043, author = {Hsiao-Ying Lin and Wen-Guey Tzeng}, title = {An Efficient Solution to The Millionaires' Problem Based on Homomorphic Encryption}, howpublished = {Cryptology ePrint Archive, Paper 2005/043}, year = {2005}, note = {\url{https://eprint.iacr.org/2005/043}}, url = {https://eprint.iacr.org/2005/043} } Note: In order to protect the privacy of readers, eprint.iacr.org does not use cookies or embedded third party content.	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.22142294049263, "perplexity": 9927.041133012326}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2023-06/segments/1674764500365.52/warc/CC-MAIN-20230206212647-20230207002647-00415.warc.gz"}
http://umr-math.univ-mlv.fr/evenements/exposes/seminaire_cristolien_d_analyse_multifractale.1338536700	## Sparse stochastic processes, fractals and wavelet analysis Type: Site: Date: 01/06/2012 - 09:45 - 10:45 Salle: Amphithéatre Vert Orateur: UNSER Michael Localisation: EPF Lausanne Localisation: Suisse Résumé: The ”self-similar” processes described in this talk are generalized versions of the classical Lévy processes. They are generalized stochastic processes (in the sense Gelfand and Vilenkin) that are solutions of (unstable) fractional stochastic differential equations (fSDE). They are described by a general innovation model that is specified by: 1) a whitening operator (fractional derivative or Laplacian), which shapes their second-order moments, and 2) a Lévy exponent $f$, which controls the sparsity of the (non-Gaussian) innovations (white Lévy noise). We give a complete characterization these processes in terms of their characteristic form (the infinite-dimensional counterpart of the characteristic function). This allows us to prove that they admit a sparse representation in a wavelet bases. We also provide evidence that wavelets allow for a better $N$ term approximation than the classical Karhunen-Loève transform (KLT), except in the Gaussian case where the processes are equivalent to Mandelbrot’s fractional Brownian motion. We also highlight a fundamental connection with spline mathematics and the construction of maximally localized basis functions (B-splines).	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9415873885154724, "perplexity": 924.1001524229092}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-09/segments/1518891812758.43/warc/CC-MAIN-20180219171550-20180219191550-00625.warc.gz"}
http://philpapers.org/s/Field%20Theory	## Search results for 'Field Theory' (try it on Scholar) 997 found Sort by: Bibliography: Quantum Field Theory in Philosophy of Physical Science 1. Hartry Field (1974). Quine and the Correspondence Theory. Philosophical Review 83 (2):200-228.score: 280.0 A correspondence theory of truth explains truth in terms of various correspondence relations (e.G., Reference) between words and the extralinguistic world. What are the consequences of quine's doctrine of indeterminacy for correspondence theories? in "ontological relativity" quine implicitly claims that correspondence theories are impossible; that is what the doctrine of 'relative reference' amounts to. But quine's doctrine of relative reference is incoherent. Those who think the indeterminacy thesis valid should not try to relativize reference, They should abandon the relation (...) My bibliography Export citation 2. Harty Field (2004). The Consistency of the Naïve Theory of Properties. Philosophical Quarterly 54 (214):78 - 104.score: 280.0 If properties are to play a useful role in semantics, it is hard to avoid assuming the naïve theory of properties: for any predicate Θ(x), there is a property such that an object o has it if and only if Θ(o). Yet this appears to lead to various paradoxes. I show that no paradoxes arise as long as the logic is weakened appropriately; the main difficulty is finding a semantics that can handle a conditional obeying reasonable laws without engendering (...) My bibliography Export citation 3. Hartry Field (1972). Tarski's Theory of Truth. Journal of Philosophy 64 (13):347-375.score: 240.0 My bibliography Export citation 4. Hartry Field (1973). Theory Change and the Indeterminacy of Reference. Journal of Philosophy 70 (14):462-481.score: 240.0 My bibliography Export citation 5. Sunny Y. Auyang (1995). How is Quantum Field Theory Possible? Oxford University Press.score: 240.0 Quantum field theory (QFT) combines quantum mechanics with Einstein's special theory of relativity and underlies elementary particle physics. This book presents a philosophical analysis of QFT. It is the first treatise in which the philosophies of space-time, quantum phenomena, and particle interactions are encompassed in a unified framework. Describing the physics in nontechnical terms, and schematically illustrating complex ideas, the book also serves as an introduction to fundamental physical theories. The philosophical interpretation both upholds the reality of (...) My bibliography Export citation 6. Harvey R. Brown & Rom Harré (eds.) (1988). Philosophical Foundations of Quantum Field Theory. Oxford University Press.score: 240.0 Quantum field theory, one of the most rapidly developing areas of contemporary physics, is full of problems of great theoretical and philosophical interest. This collection of essays is the first systematic exploration of the nature and implications of quantum field theory. The contributors discuss quantum field theory from a wide variety of standpoints, exploring in detail its mathematical structure and metaphysical and methodological implications. My bibliography Export citation 7. R. G. Beil (2003). Finsler Geometry and Relativistic Field Theory. Foundations of Physics 33 (7):1107-1127.score: 240.0 Finsler geometry on the tangent bundle appears to be applicable to relativistic field theory, particularly, unified field theories. The physical motivation for Finsler structure is conveniently developed by the use of “gauge” transformations on the tangent space. In this context a remarkable correspondence of metrics, connections, and curvatures to, respectively, gauge potentials, fields, and energy-momentum emerges. Specific relativistic electromagnetic metrics such as Randers, Beil, and Weyl can be compared. My bibliography Export citation 8. Hartry Field (1992). A Nominalistic Proof of the Conservativeness of Set Theory. Journal of Philosophical Logic 21 (2):111 - 123.score: 240.0 My bibliography Export citation 9. Mark A. Rubin (2002). Locality in the Everett Interpretation of Quantum Field Theory. Foundations of Physics 32 (10):1495-1523.score: 240.0 Recently it has been shown that transformations of Heisenberg-picture operators are the causal mechanism which allows Bell-theorem-violating correlations at a distance to coexist with locality in the Everett interpretation of quantum mechanics. A calculation to first order in perturbation theory of the generation of EPRB entanglement in nonrelativistic fermionic field theory in the Heisenberg picture illustrates that the same mechanism leads to correlations without nonlocality in quantum field theory as well. An explicit transformation is given (...) My bibliography Export citation 10. Gerard ’T. Hooft (2013). Duality Between a Deterministic Cellular Automaton and a Bosonic Quantum Field Theory in 1+1 Dimensions. Foundations of Physics 43 (5):597-614.score: 240.0 Methods developed in a previous paper are employed to define an exact correspondence between the states of a deterministic cellular automaton in 1+1 dimensions and those of a bosonic quantum field theory. The result may be used to argue that quantum field theories may be much closer related to deterministic automata than what is usually thought possible. My bibliography Export citation 11. Friedrich W. Hehl & Yuri N. Obukhov (2008). An Assessment of Evans' Unified Field Theory II. Foundations of Physics 38 (1):38-46.score: 240.0 Evans attempted to develop a classical unified field theory of gravitation and electromagnetism on the background of a spacetime obeying a Riemann-Cartan geometry. In an accompanying paper I, we analyzed this theory and summarized it in nine equations. We now propose a variational principle for a theory that implements some of the ideas that have been (imprecisely) indicated by Evans and show that it yields two field equations. The second field equation is algebraic in (...) My bibliography Export citation 12. Friedrich W. Hehl (2008). An Assessment of Evans' Unified Field Theory I. Foundations of Physics 38 (1):7-37.score: 240.0 Evans developed a classical unified field theory of gravitation and electromagnetism on the background of a spacetime obeying a Riemann-Cartan geometry. This geometry can be characterized by an orthonormal coframe ϑ α and a (metric compatible) Lorentz connection Γ α β . These two potentials yield the field strengths torsion T α and curvature R α β . Evans tried to infuse electromagnetic properties into this geometrical framework by putting the coframe ϑ α to be proportional to (...) My bibliography Export citation 13. score: 240.0 My bibliography Export citation 14. score: 240.0 My bibliography Export citation 15. score: 240.0 In the paper it will be shown that Reichenbach’s Weak Common Cause Principle is not valid in algebraic quantum field theory with locally finite degrees of freedom in general. Namely, for any pair of projections A, B supported in spacelike separated double cones ${\mathcal{O}}_{a}$ and ${\mathcal{O}}_{b}$ , respectively, a correlating state can be given for which there is no nontrivial common cause (system) located in the union of the backward light cones of ${\mathcal{O}}_{a}$ and ${\mathcal{O}}_{b}$ and commuting with (...) My bibliography Export citation 16. Meinard Kuhlmann (2010). Why Conceptual Rigour Matters to Philosophy: On the Ontological Significance of Algebraic Quantum Field Theory. [REVIEW] Foundations of Physics 40 (9):1625-1637.score: 240.0 I argue that algebraic quantum field theory (AQFT) permits an undisturbed view of the right ontology for fundamental physics, whereas standard (or Lagrangian) QFT offers different mutually incompatible ontologies.My claim does not depend on the mathematical inconsistency of standard QFT but on the fact that AQFT has the same concerns as ontology, namely categorical parsimony and a clearly structured hierarchy of entities. My bibliography Export citation 17. A. Zee (2010). Quantum Field Theory in a Nutshell. Princeton University Press.score: 240.0 Since it was first published, Quantum Field Theory in a Nutshell has quickly established itself as the most accessible and comprehensive introduction to this profound and deeply fascinating area of theoretical physics. Now in this fully revised and expanded edition, A. Zee covers the latest advances while providing a solid conceptual foundation for students to build on, making this the most up-to-date and modern textbook on quantum field theory available. -/- This expanded edition features several additional (...) My bibliography Export citation 18. score: 240.0 My bibliography Export citation 19. Yuichiro Kitajima (2013). EPR States and Bell Correlated States in Algebraic Quantum Field Theory. Foundations of Physics 43 (10):1182-1192.score: 240.0 A mathematical rigorous definition of EPR states has been introduced by Arens and Varadarajan for finite dimensional systems, and extended by Werner to general systems. In the present paper we follow a definition of EPR states due to Werner. Then we show that an EPR state for incommensurable pairs is Bell correlated, and that the set of EPR states for incommensurable pairs is norm dense between two strictly space-like separated regions in algebraic quantum field theory. My bibliography Export citation 20. Miklos Redei & Stephen J. Summers (2002). Local Primitive Causality and the Common Cause Principle in Quantum Field Theory. Foundations of Physics 32 (3):335-355.score: 240.0 If $\mathcal{A}$ (V) is a net of local von Neumann algebras satisfying standard axioms of algebraic relativistic quantum field theory and V 1 and V 2 are spacelike separated spacetime regions, then the system ( $\mathcal{A}$ (V 1 ), $\mathcal{A}$ (V 2 ), φ) is said to satisfy the Weak Reichenbach's Common Cause Principle iff for every pair of projections A∈ $\mathcal{A}$ (V 1 ), B∈ $\mathcal{A}$ (V 2 ) correlated in the normal state φ there exists a (...) My bibliography Export citation 21. Paul Teller (1995). An Interpretive Introduction to Quantum Field Theory. Princeton University Press.score: 240.0 Quantum mechanics is a subject that has captured the imagination of a surprisingly broad range of thinkers, including many philosophers of science. Quantum field theory, however, is a subject that has been discussed mostly by physicists. This is the first book to present quantum field theory in a manner that makes it accessible to philosophers. Because it presents a lucid view of the theory and debates that surround the theory, An Interpretive Introduction to Quantum (...) My bibliography Export citation 22. score: 240.0 This paper will examine the implications of an extended “field theory of information,” suggested by Wolfhart Pannenberg, specifically in the Christian understanding of creation. The paper argues that the Holy Spirit created the world as field, a concept from physics, and the creation is directed by the logos utilizing information. Taking into account more recent developments of information theory, the essay further suggests that present creation has a causal impact upon the information utilized in creation. In (...) My bibliography Export citation 23. P. A. Marchetti (2010). Spin-Statistics Transmutation in Quantum Field Theory. Foundations of Physics 40 (7):746-764.score: 240.0 Spin-statistics transmutation is the phenomenon occurring when a “dressing” transformation introduced for physical reasons (e.g. gauge invariance) modifies the “bare” spin and statistics of particles or fields. Historically, it first appeared in Quantum Mechanics and in semiclassical approximation to Quantum Field Theory. After a brief historical introduction, we sketch how to describe such phenomenon in Quantum Field Theory beyond the semiclassical approximation, using a path-integral formulation of euclidean correlation functions, exemplifying with anyons, dyons and skyrmions. My bibliography Export citation 24. score: 240.0 If the general arguments concerning theinvolvement of variation and selection inexplanations of fit'' are valid, then variationand selection explanations should beappropriate, or at least potentiallyappropriate, outside the paradigm historisticdomains of biology and knowledge. In thisdiscussion, I wish to indicate some potentialroles for variation and selection infoundational physics â specifically inquantum field theory. I will not be attemptingany full coherent ontology for quantum fieldtheory â none currently exists, and none islikely for at least the short term future. Instead, I (...) No categories My bibliography Export citation 25. Mark A. Rubin (2011). Observers and Locality in Everett Quantum Field Theory. Foundations of Physics 41 (7):1236-1262.score: 240.0 A model for measurement in collapse-free nonrelativistic fermionic quantum field theory is presented. In addition to local propagation and effectively-local interactions, the model incorporates explicit representations of localized observers, thus extending an earlier model of entanglement generation in Everett quantum field theory (Rubin in Found. Phys. 32:1495–1523, 2002). Transformations of the field operators from the Heisenberg picture to the Deutsch-Hayden picture, involving fictitious auxiliary fields, establish the locality of the model. The model is applied to (...) My bibliography Export citation 26. G. C. Field (1953). What Is Political Theory? Proceedings of the Aristotelian Society 54:145 - 166.score: 240.0 My bibliography Export citation 27. G. C. Field (1923). Aristotle's Account of the Historical Origin of the Theory of Ideas. Classical Quarterly 17 (3-4):113-.score: 240.0 Whatthe influences were which led to the development and formulation of the so-called Theory of Ideas, usually associated with the name of Plato, is a question of perennial interest. And the interest has been increased by the vigorous controversy that, during the last ten years, has been conducted round the question of the exact part played by Socrates in the development of this theory. All the available evidence on the question is accessible and familiar to students of Greek (...) My bibliography Export citation 28. score: 240.0 My bibliography Export citation 29. Francesco Giacosa (2012). Non-Exponential Decay in Quantum Field Theory and in Quantum Mechanics: The Case of Two (or More) Decay Channels. Foundations of Physics 42 (10):1262-1299.score: 240.0 We study the deviations from the exponential decay law, both in quantum field theory (QFT) and quantum mechanics (QM), for an unstable particle which can decay in (at least) two decay channels. After a review of general properties of non-exponential decay in QFT and QM, we evaluate in both cases the decay probability that the unstable particle decays in a given channel in the time interval between t and t+dt. An important quantity is the ratio of the probability (...) My bibliography Export citation 30. G. C. Field (1932). Moral Theory. London, Methuen & Co., Ltd..score: 240.0 My bibliography Export citation 31. G. C. Field (1966). Moral Theory: An Introduction to Ethics. London, Methuen.score: 240.0 My bibliography Export citation 32. G. C. Field (1928). The Inaugural Address: The Origin and Development of Plato's Theory of Ideas. Aristotelian Society Supplementary Volume 8:1 - 30.score: 240.0 My bibliography Export citation 33. score: 224.0 An examination is made of the way in which particles emerge from linear, bosonic, massive quantum field theories. Two different constructions of the one-particle subspace of such theories are given, both illustrating the importance of the interplay between the quantum-mechanical linear structure and the classical one. Some comments are made on the Newton-Wigner representation of one-particle states, and on the relationship between the approach of this paper and those of Segal, and of Haag and Ruelle. My bibliography Export citation 34. Bert Schroer (2010). Localization and the Interface Between Quantum Mechanics, Quantum Field Theory and Quantum Gravity I. Studies in History and Philosophy of Science Part B 41 (2):104-127.score: 216.0 It is shown that there are significant conceptual differences between QM and QFT which make it difficult to view the latter as just a relativistic extension of the principles of QM. At the root of this is a fundamental distiction between Born-localization in QM (which in the relativistic context changes its name to Newton–Wigner localization) and modular localization which is the localization underlying QFT, after one separates it from its standard presentation in terms of field coordinates. The first comes (...) My bibliography Export citation 35. Bert Schroer (2010). Localization and the Interface Between Quantum Mechanics, Quantum Field Theory and Quantum Gravity II. Studies in History and Philosophy of Science Part B 41 (4):293-308.score: 216.0 The main topics of this second part of a two-part essay are some consequences of the phenomenon of vacuum polarization as the most important physical manifestation of modular localization. Besides philosophically unexpected consequences, it has led to a new constructive “outside-inwards approach” in which the pointlike fields and the compactly localized operator algebras which they generate only appear from intersecting much simpler algebras localized in noncompact wedge regions whose generators have extremely mild almost free field behavior. -/- Another consequence (...) My bibliography Export citation 36. H. Kleinert (2014). Quantum Field Theory of Black-Swan Events. Foundations of Physics 44 (5):546-556.score: 216.0 Free and weakly interacting particles are described by a second-quantized nonlinear Schrödinger equation, or relativistic versions of it. They describe Gaussian random walks with collisions. By contrast, the fields of strongly interacting particles are governed by effective actions, whose extremum yields fractional field equations. Their particle orbits perform universal Lévy walks with heavy tails, in which rare events are much more frequent than in Gaussian random walks. Such rare events are observed in exceptionally strong windgusts, monster or rogue waves, (...) My bibliography Export citation 37. Thomas Fuß (2002). SU(3) Local Gauge Field Theory as Effective Dynamics of Composite Gluons. Foundations of Physics 32 (11):1737-1755.score: 216.0 The effective dynamics of quarks is described by a nonperturbatively regularized NJL model equation with canonical quantization and probability interpretation. The quantum theory of this model is formulated in functional space and the gluons are considered as relativistic bound states of colored quark-antiquark pairs. Their wave functions are calculated as eigenstates of hardcore equations, and their effective dynamics is derived by weak mapping in functional space. This leads to the phenomenological SU(3) gauge invariant gluon equations in functional formulation, i.e., (...) My bibliography Export citation 38. Olivier Driessens (2013). Celebrity Capital: Redefining Celebrity Using Field Theory. [REVIEW] Theory and Society 42 (5):543-560.score: 216.0 No categories My bibliography Export citation 39. Jan Rzewuski (1967). Field Theory. London, Iliffe.score: 216.0 v. 1. Classical theory.--v. 2. Functional formulation of S-matrix theory. My bibliography Export citation 40. J. McFadden (2002). The Conscious Electromagnetic Information (Cemi) Field Theory: The Hard Problem Made Easy? Journal of Consciousness Studies 9 (8):45-60.score: 210.0 In the April 2002 edition of JCS I outlined the conscious electromagnetic information field theory, claiming that consciousness is that component of the brain's electromagnetic field that is downloaded to motor neurons and is thereby capable of communicating its informational content to the outside world. In this paper I demonstrate that the theory is robust to criticisms. I further explore implications of the theory particularly as regards the relationship between electromagnetic fields, information, the phenomenology of (...) My bibliography Export citation 41. Susan Pockett (2002). Difficulties with the Electromagnetic Field Theory of Consciousness. Journal of Consciousness Studies 9 (4):51-56.score: 210.0 The author's version of the electromagnetic field theory of consciousness is stated briefly and then three difficulties with the theory are discussed. The first is a purely technical problem: how to measure accurately enough the spatial properties of the fields which are proposed to be conscious and then how to generate these artificially, so that the theory can be tested. The second difficulty might also be merely technical, or it might be substantive and fatal to the (...) My bibliography Export citation 42. Heinz Werner & Seymour Wapner (1952). Experiments on Sensory-Tonic Field Theory of Perception: IV. Effect of Initial Position of a Rod on Apparent Verticality. Journal of Experimental Psychology 43 (1):68.score: 210.0 My bibliography Export citation 43. score: 210.0 My bibliography Export citation 44. Seymour Wapner & Heinz Werner (1952). Experiments on Sensory-Tonic Field Theory of Perception: V. Effect of Body Status on the Kinesthetic Perception of Verticality. Journal of Experimental Psychology 44 (2):126.score: 210.0 My bibliography Export citation 45. score: 210.0 My bibliography Export citation 46. score: 210.0 My bibliography Export citation 47. score: 210.0 My bibliography Export citation 48. Kullervo Rainio (1986). Stochastic Field Theory of Behavior. Academic Bookstore [Distributor].score: 210.0 My bibliography Export citation 49. score: 210.0	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8428409695625305, "perplexity": 2317.790334102624}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-14/segments/1427131295084.53/warc/CC-MAIN-20150323172135-00160-ip-10-168-14-71.ec2.internal.warc.gz"}
https://arxiv.org/abs/1603.03367?context=cond-mat.str-el	cond-mat.str-el Title:High pressure magnetic state of MnP probed by means of muon-spin rotation Abstract: We report a detailed $\mu$SR study of the pressure evolution of the magnetic order in the manganese based pnictide MnP, which has been recently found to undergo a superconducting transition under pressure once the magnetic ground state is suppressed. Using the muon as a volume sensitive local magnetic probe, we identify a ferromagnetic state as well as two incommensurate helical states (with propagation vectors ${\bf Q}$ aligned along the crystallographic $c-$ and $b-$directions, respectively) which transform into each other through first order phase transitions as a function of pressure and temperature. Our data appear to support that the magnetic state from which superconductivity develops at higher pressures is an incommensurate helical phase. Comments: 11 pages, 9 figures Subjects: Superconductivity (cond-mat.supr-con); Strongly Correlated Electrons (cond-mat.str-el) Journal reference: Phys. Rev. B 93, 180509 (2016) DOI: 10.1103/PhysRevB.93.180509 Cite as: arXiv:1603.03367 [cond-mat.supr-con] (or arXiv:1603.03367v1 [cond-mat.supr-con] for this version) Submission history From: Rustem Khasanov [view email] [v1] Thu, 10 Mar 2016 18:54:24 UTC (470 KB)	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3279344439506531, "perplexity": 3717.3984411871616}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-22/segments/1558232256980.46/warc/CC-MAIN-20190522223411-20190523005411-00044.warc.gz"}
https://www.dummies.com/programming/electronics/diy-projects/how-rectifier-circuits-work-in-electronics/	How Rectifier Circuits Work in Electronics - dummies # How Rectifier Circuits Work in Electronics One of the most common uses for rectifier diodes in electronics is to convert household alternating current into direct current that can be used as an alternative to batteries. The rectifier circuit, which is typically made from a set of cleverly interlocked diodes, converts alternating current to direct current. In household current, the voltage swings from positive to negative in cycles that repeat 60 times per second. If you place a diode in series with an alternating current voltage, you eliminate the negative side of the voltage cycle, so you end up with just positive voltage. If you look at the waveform of the voltage coming out of this rectifier diode, you’ll see that it consists of intervals that alternate between a short increase of voltage and periods of no voltage at all. This is a form of direct current because it consists entirely of positive voltage. However, it pulsates: first it’s on, then it’s off, then it’s on again, and so on. Overall, voltage rectified by a single diode is off half of the time. So although the positive voltage reaches the same peak level as the input voltage, the average level of the rectified voltage is only half the level of the input voltage. This type of rectifier circuit is sometimes called a half-wave rectifier because it passes along only half of the incoming alternating current waveform. A better type of rectifier circuit uses four rectifier diodes, in a special circuit called a bridge rectifier. Look at how this rectifier works on both sides of the alternating current input signal: • In the first half of the AC cycle, D2 and D4 conduct because they’re forward biased. Positive voltage is on the anode of D2 and negative voltage is on the cathode of D4. Thus, these two diodes work together to pass the first half of the signal through. • In the second half of the AC cycle, D1 and D3 conduct because they’re forward biased: Positive voltage is on the anode of D1, and negative voltage is on the cathode of D3. The net effect of the bridge rectifier is that both halves of the AC sine wave are allowed to pass through, but the negative half of the wave is inverted so that it becomes positive.	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8922244310379028, "perplexity": 671.2039715201803}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-30/segments/1563195526888.75/warc/CC-MAIN-20190721040545-20190721062545-00049.warc.gz"}
https://space.stackexchange.com/tags/ulysses/hot	Tag Info 25 The performance of Shuttle-Centaur would have greatly exceeded that of either the Atlas-Centaur or Titan-Centaur combination. Neither the Atlas nor Titan were able to put a fully fueled Centaur into Earth orbit using only their lower stages. The Centaur would have burned part of its propellant completing the orbital insertion. In contrast, the shuttle ... 5 Yes. Ulysses was quite a light weight, only 370 kg. For comparison, the Galileo probe, which was put in to Jupiter's atmosphere, weighted almost that much, and that was a small part of Galileo, which in total weighed about 2562 kg. Much of that mass was to orbit the planet, also the communications was supposed to be better, as the prime part of Galileo was ... 4 Several terse online references state that the nutation anomaly was managed by the use of "Conscan" or CONSCAN, for example The only other problem of any significance has been a nutation-like motion which built up following deployment of the 7.5-meter (25-foot) axial radio wave experiment antenna shortly after launch. This disturbance was apparently ... 4 In simple terms, gravity pulls an object directly towards another object. As an analogy, if you are running down the street and grab hold of a lamp post with your left hand you will swing around it to the left, if you grab it with your right you will swing to the right. You can use this to do a u-turn, letting go whenever you or going the right direction, or ... 3 I don't know did anything change since 2017, but here is complete and bulky pdf https://www.researchgate.net/publication/313365623_Laser_Interferometer_Space_Antenna. What exactly is eLISA How large will eLISA be? After several iterations current mission design (LISA, not eLISA anymore) is planned to be: -Space gravitational detector consisting of 3 ... 2 A polar LEO orbit is still a equatorial heliocentric orbit (since that describes the Earth's orbit around the sun). To change from a equatorial heliocentric to polar heliocentric requires a lot of Delta v. The final orbit wasn't circular, but we can get an order-of-magnitude figure for the energy required by using the circular plane change approximation. ... 2 As stated in the comments above, the trajectory adjustment took place on the eighth of July 1991, before Ulysses swung by Jupiter. For more information on its trajectory, please consult: http://adsbit.harvard.edu//full/1992A%26AS...92..207W/0000209.000.html By changing the start date of the simulation to the first of August 1991, half a year before the ... 1 I'll elaborate on some points because I find the Ulysses mission really compelling. I'll quote further from the references cited in @OrganicMarble's award-winning answer The ULYSSES Mission, Wenzel, K. P., Marsden, R. G., Page, D. E., & Smith, E. J., Astronomy and Astrophysics Supplement, Vol.92, NO. 2/JAN, P. 207, 1992 Spacecraft description 5.1 ... Only top voted, non community-wiki answers of a minimum length are eligible	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8345178365707397, "perplexity": 2374.0761019342444}, "config": {"markdown_headings": false, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-34/segments/1596439738573.99/warc/CC-MAIN-20200809192123-20200809222123-00305.warc.gz"}
https://infoscience.epfl.ch/record/188522	## Measurement of the dynamics in ski jumping using a wearable inertial sensor-based system Dynamics is a central aspect of ski jumping, particularly during take-off and stable flight. Currently, measurement systems able to measure ski jumping dynamics (e.g., 3D cameras, force plates) are complex and only available in few research centres worldwide. This study proposes a method to determine dynamics using a wearable inertial sensor-based system which can be used routinely on any ski jumping hill. The system automatically calculates characteristic dynamic parameters during take-off (position and velocity of the center of mass perpendicular to the table, force acting on the center of mass perpendicular to the table, and somersault angular velocity) and stable flight (total aerodynamic force). Furthermore, the acceleration of the ski perpendicular to the table was quantified to characterize the skis lift at take-off. The system was tested with two groups of 11 athletes with different jump distances. The force acting on the center of mass, acceleration of the ski perpendicular to the table, somersault angular velocity, and total aerodynamic force were different between groups and correlated with the jump distances. Furthermore, all dynamic parameters were within the range of prior studies based on stationary measurement systems, except for the center of mass mean force which was slightly lower. Published in: Journal of Sports Sciences, 32, 6, 591-600 Year: 2014 Publisher: Abingdon, Taylor & Francis ISSN: 0264-0414 Keywords: Laboratories:	{"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8570501804351807, "perplexity": 1472.0708209802042}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-51/segments/1544376823618.14/warc/CC-MAIN-20181211104429-20181211125929-00461.warc.gz"}
http://math.stackexchange.com/questions/279771/analytic-function-in-open-connected-set-that-is-bounded-by-another-analytic-func	# Analytic function in open connected set that is bounded by another analytic function Let $G$ be an open connected set and $f, g$ analytic functions on $G$. If $\|f\|\le \|g\|$ then there exists an analytic function $h$ such that $f(z)=h(z)g(z)$. We know $\|f/g\|\le 1$ everywhere in $G$, and so $f/g$ is bounded near any singularities. (The singularities must be isolated, for otherwise they have a limit and the function is identically zero.) So we can extend $f/g$ to be analytic in all of $G$. But where do I go from here? Presumably the connectedness of $G$ is important, but I don't see how it helps in manipulating $f$ and $g$ to make an $h$ appear EDIT: As pointed out in the comments, I am already done. Take $h= f/g$. - What's the problem? You already extended $f/g$ to be analytic in $G$. That's your $h$. – Robert Israel Jan 16 '13 at 3:24 Excuse my while I facepalm myself to death. Thank you – Bey Jan 16 '13 at 3:26 Bey: You might as well post an answer. – Jonas Meyer Jan 16 '13 at 3:31 ## 1 Answer As has been pointed out, there's actually nothing left for me to do. For completeness, here's the solution: Since $\|f(z)\|\le \|g(z)\|$ for all $z\in G$, we have $\|f(z)/g(z)\|\le 1$ everywhere in $G$. So $h(z):=f(z)/g(z)$ is bounded in a neighborhood of any possible singularities, meaning any singularity is removable. Hence, we can define $h$ to be analytic on all of $G$. Now we simply notice that $f(z)=h(z)g(z)$ and we're done. -	{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9804278612136841, "perplexity": 151.29656609791078}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-30/segments/1469257824037.46/warc/CC-MAIN-20160723071024-00166-ip-10-185-27-174.ec2.internal.warc.gz"}