bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of D‐optimal design to model and the analysis of the effect of the draw ratio on some physical properties of hot multistage drawn nylon 6 fibers
Authors: Rahbar Ruhollah Semnani , Haji Aminoddin 
Published: April 2013

ABSTRACTIn this article, we present an experimental design methodology for studying the effect of the draw ratio on the physical properties of nylon 6 fibers on hot multistage drawing. A response surface methodology involving D‐optimal design was used for the modeling and optimization. According to the analysis of variance results, the proposed models could be used to navigate the design space. We found that the responses of the tenacity and initial modulus were very sensitive to the factor of the second‐stage draw ratio, and the shrinkage response was governed by the factor of the third‐stage draw ratio. The results show a good agreement between the experimental and model predictions with high correlation coefficients. The operation conditions for obtaining the drawn yarn with the highest tenacity and initial modulus and low shrinkage are proposed. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1337‐1344, 2013
Characterization and dual functionalization of polystyrene with propionic anhydride and cyanate derivatives
Authors: Gunes Hasan Huseyin , Okudan Ahmet 
Published: April 2013

ABSTRACT First, Friedel–Crafts reactions were used for the acylation process. For this, polystyrene (PS) was reacted with propionic anhydride in the presence of Lewis acid catalyst. The amount of acyl group linked PS as a result of acylation has been identified as volumetric. Second, the bromination and lithiation reactions of acylated PS containing carbonyl groups were realized. Also, the lithiated PS containing acyl groups has been modified a second time with various isocyanates and isothiocyanate derivatives in the presence of n‒BuLi catalyst. Some important reaction parameters were assigned in order to optimize the process. The structure all of the products were characterized by Fourier transform infrared, 1H NMR (Proton Nuclear Magnetic Resonance), and thermogravimetric methods. In addition, reaction yields were determined according to the result of elemental analysis. Dual functionalization yields were realized between 62.2% and 69.9%. For kinetic analysis, the TG/DTG (Thermal Gravimetric Analysis/Differantial Thermal Analysis) data obtained at three different heating rates were processed by Kissinger–Akahira–Sunose method. The results demonstrated that the acylation reaction, bromination and lithiation reactions, and dual functionalization reactions with cyanate derivatives can be carried out to obtain a significantly functionalized polymer. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1351‐1362, 2013
Mechanical and dielectric properties of short‐carbon‐fibers/epoxy‐modified‐organic‐silicone‐resin as heat resistant microwave absorbing coatings
Authors: Huang Shanshan , Zhou Wancheng , Luo Fa , Zhu Dongmei 
Published: April 2013

ABSTRACTHeat resistant microwave absorbing coatings were prepared by brushing and thereafter heat treatment, using epoxy modified organic silicone resin as binding material, short carbon fibers (Csf) as absorbers, talcum powder and glass powder as filling materials. The mechanical and dielectric properties of the coatings before and after heat treatment at 600°C for 10 mins were studied. The results showed that the adhesive power after heat treatment enhances remarkably, both the real (ε′) and imaginary (ε″) parts of the permittivity of the coatings increase with increasing Csf content in the frequency range of 8.2–12.4 GHz. The calculation value of the reflection loss as single layer absorber indicates that epoxy modified organic silicone resin coatings containing short carbon fibers could be a promising radar absorbing material applied at high temperature. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1392‐1398, 2013
Effect of 1,3,5‐trialkyl‐benzenetricarboxylamide on the crystallization of poly(lactic acid)
Authors: Wang Ting , Yang Yong , Zhang Chuanzhi , Tang Zhaobin , Na Haining , Zhu Jin 
Published: April 2013

ABSTRACTA series of 1,3,5‐trialkyl‐benzenetricarboxylamides (BTA‐Rs) with different side‐chain lengths of n‐alkyl are synthesized to use as nucleating agents of poly (lactic acid) (PLA). Crystallization rate of PLA is detailed discussed in nonisothermal melt‐crystallization with addition of the synthesized nucleating agents. Among these BTA‐Rs, BTA‐n‐butyl (BTA‐nBu) shows the most excellent nucleation ability for PLA. The influences of BTA‐nBu on the nonisothermal melt‐crystallization and cold‐crystallization from the glassy state, isothermal crystallization, crystalline structure, and spherulite morphology of PLA are investigated. It is found that 0.8 wt % is the optimal weight fraction of BTA‐nBu to improve the crystallization of PLA. In the case of isothermal melt‐crystallization from melt, the addition of BTA‐nBu shortens the crystallization half‐time and speeds up the crystallization rate of PLA with no discernible effect on the crystalline structure. Besides, BTA‐nBu nucleated PLA exhibits smaller spherulites size and larger nucleation density than that of pure PLA. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1328‐1336, 2013
Systematic investigation on parameters of solution blown micro/nanofibers using response surface methodology based on box‐Behnken design
Authors: Lou Huiqing , Li Wentao , Li Chulin , Wang Xinhou 
Published: April 2013

ABSTRACTResponse surface methodology, based on the four‐factor, three‐level Box‐Behnken design, has been utilized to facilitate a more systematic understanding of the solution and processing parameters of solution blown polyethylene oxide (PEO) micro/nanofibers. The factors investigated include air pressure, solution concentration, nozzle diameter, and injection rate. Fiber diameters, ranging from 137 to 1982 nm, are associated with these variables by applying a response surface model. The linear coefficients of air pressure and solution concentration, the interactive effect between air pressure and injection rate as well as the quadratic terms of nozzle diameter and injection rate are demonstrated statistically significant. Verification of the response surface model is successfully accomplished. Consequently, this study puts forward an overview of the effect of solution and technical parameters on solution blown submicron PEO fibers and provides a train of thought for fabricating other micro/nanofibers. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1383‐1391, 2013
Spectral and time‐frequency analyses of freeway traffic flow
Authors: Sun Lu 
Published: April 2013

SUMMARYThis paper uses spectral and time‐frequency analyses to treat three macroscopic traffic characteristics, namely, time mean speed, volume and occupancy as stochastic processes. Spectral and time‐frequency analyses are performed to characterize power spectral density (PSD), cross‐PSD, autocorrelation and cross‐correlation of these characteristics using TransGuide traffic data collected from four different freeways. It is found that low‐frequency components dominate the PSDs of speed, volume and occupancy at all times. The magnitude of PSDs decreases dramatically as frequency increases and remains almost at a constant level in high‐frequency regimes. A power law is found to exist, which describes the relationship between the frequency and the PSD of traffic characteristics. It is also found that speed can be properly modeled by a narrowband low‐pass stochastic process in a low‐frequency regime and by a nonzero mean white noise in a high‐frequency regime. Strong periodicities and synchronization are both shown in traffic flow. A variety of frequencies can be excited by congestion, and there is no dominant frequency found in stop‐and‐go traffic. Copyright © 2013 John Wiley & Sons, Ltd.
Determination of dobutamine hydrochloride by enzymatic catalytic spectrofluorimetry
Authors: Tian Feng‐Shou , Chen Ya‐Hong , Liang Hai‐Yan 
Published: April 2013

ABSTRACTA highly sensitive and simple spectrofluorimetric method for the determination of dobutamine hydrochloride based on its inhibitory effect on the hemoglobin‐catalyzed reaction of H2O2 and l‐tyrosine was developed. The relationship between the concentration of dobutamine hydrochloride and the fluorescence quenching (ΔF) of the system is linear under the optimal experimental conditions. The calibration graph is linear in the range 2.00 × 10‐7 to 3.00 × 10‐6 g/mL with a limit of detection of 4.83 × 10‐9 g/mL. This method can be used for the determination of dobutamine hydrochloride in its pharmaceutical formulations and in urine with satisfactory results. Copyright © 2013 John Wiley & Sons, Ltd.
Directed evolution of a highly efficient cellobiose utilizing pathway in an industrial Saccharomyces cerevisiae strain
Authors: Yuan Yongbo , Zhao Huimin 
Published: April 2013

ABSTRACTBalancing and increasing the flux through an engineered heterologous pathway in a target organism to achieve high yield and productivity remains an overwhelming challenge in metabolic engineering. Here we report a novel strategy combining directed evolution and promoter engineering for rapid and efficient multi‐gene pathway optimization. As proof of concept, this strategy was applied to optimize a cellobiose utilizing pathway in an industrial Saccharomyces cerevisiae strain for highly efficient cellulosic biofuels production. The resulting strain exhibited significantly higher cellobiose consumption rate (6.41‐fold) and ethanol productivity (6.36‐fold) compared to its parent strain. This study also showed that both the ratios and absolute values of the expression levels of the genes in the cellobiose utilizing pathway play an important role in cellobiose uptake, and β‐glucose is likely one of the key factors affecting cellobiose metabolism. Biotechnol. Biotechnol. Bioeng. 2013;110: 2874–2881. © 2013 Wiley Periodicals, Inc.
Optimization of outdoor cultivation in flat panel airlift reactors for lipid production by Chlorella vulgaris
Authors: Münkel Ronja , Schmid‐Staiger Ulrike , Werner Achim , Hirth Thomas 
Published: April 2013

ABSTRACTMicroalgae are discussed as a potential renewable feedstock for biofuel production. The production of highly concentrated algae biomass with a high fatty acid content, accompanied by high productivity with the use of natural sunlight is therefore of great interest. In the current study an outdoor pilot plant with five 30 L Flat Panel Airlift reactors (FPA) installed southwards were operated in 2011 in Stuttgart, Germany. The patented FPA reactor works on the basis of an airlift loop reactor and offers efficient intermixing for homogeneous light distribution. A lipid production process with the microalgae Chlorella vulgaris (SAG 211‐12), under nitrogen and phosphorous deprivation, was established and evaluated in regard to the fatty acid content, fatty acid productivity and light yield. In the first set of experiments limitations caused by restricted CO2 availability were excluded by enriching the media with NaOH. The higher alkalinity allows a higher CO2 content of supplied air and leads to doubling of fatty acid productivity. The second set of experiments focused on how the ratio of light intensity to biomass concentration in the reactor impacts fatty acid content, productivity and light yield. The specific light availability was specified as mol photons on the reactor surface per gram biomass in the reactor. This is the first publication based on experimental data showing the quantitative correlation between specific light availability, fatty acid content and biomass light yield for a lipid production process under nutrient deprivation and outdoor conditions. High specific light availability leads to high fatty acid contents. Lower specific light availability increases fatty acid productivity and biomass light yield. An average fatty acid productivity of 0.39 g L−1 day−1 for a 12 days batch process with a final fatty acid content of 44.6% [w/w] was achieved. Light yield of 0.4 g mol photons−1 was obtained for the first 6 days of cultivation. Biotechnol. Bioeng. 2013;110: 2882–2893. © 2013 Wiley Periodicals, Inc.
In non‐small cell lung cancer mitogenic signaling leaves Sprouty1 protein levels unaffected
Authors: Kral Rosana Maria , Mayer Christoph‐Erik , Vanas Vanita , Gsur Andrea , Sutterlüty‐Fall Hedwig 
Published: April 2013

Sprouty1 protein belongs to a family of receptor tyrosine kinase‐mediated signaling inhibitors, whose members are usually regulated by growth factors to form a negative feedback loop. Correspondingly fluctuations of Sprouty1 mRNA in response to single growth factors have been observed.In this report, we investigate Sprouty1 protein levels and show that in non‐small cell lung carcinoma‐derived cells, the expression levels are unaffected by the serum content in the cellular environment. Although cells harboring K‐Ras mutations express insignificant higher Sprouty1 levels, ectopic expression of constitutive active Ras in normal human lung fibroblasts fails to augment Sprouty1 protein content. Furthermore, serum starvation for three days has no influence on Sprouty1 expression and addition of serum or of singular growth factors leaves Sprouty protein levels unchanged. Cell cycle analysis reveals that Sprouty1 levels remain constant throughout the whole cell cycle. These data demonstrate that Sprouty1 expression is not connected with mitogenic signaling and cell proliferation. Copyright © 2013 John Wiley & Sons, Ltd.
ChemInform Abstract: K2FeGe3Se8: A New Antiferromagnetic Iron Selenide.
Authors: Feng Kai , Wang Wendong , He Ran , Kang Lei , Yin Wenlong , Lin Zheshuai , Yao Jiyong , Shi Youguo , Wu Yicheng 
Published: April 2013

AbstractThe title compound is synthesized from a mixture of K2Se, FeSe, and GeSe2 (silica tube, 1173 K, 48 h) and characterized by single crystal XRD, diffuse reflectance spectroscopy, specific heat and magnetic susceptibility measurements, and DFT calculations.
ChemInform Abstract: New Structure Type in the Mixed‐Valent Compound YbCu4Ga8.
Authors: Subbarao Udumula , Gutmann Matthias J. , Peter Sebastian C. 
Published: April 2013

AbstractLarge single crystals of YbCu4Ga8 are prepared by the metal flux technique using excess Ga as fluxing agent (evacuated quartz tube; 1.
ChemInform Abstract: Enhanced Photoresponsive Ultrathin Graphitic‐Phase C3N4 Nanosheets for Bioimaging.
Authors: Zhang Xiaodong , Xie Xiao , Wang Hui , Zhang Jiajia , Pan Bicai , Xie Yi 
Published: April 2013

AbstractUltrathin graphitic‐phase C3N4 nanosheets are prepared by a liquid exfoliation route from bulk C3N4 in water.
ChemInform Abstract: A Sodium Vanadium Three‐Fluorophosphate Cathode for Rechargeable Batteries Synthesized by Carbothermal Reduction.
Authors: Song Weixin , Liu Suqin 
Published: April 2013

AbstractNa3V2(PO4)2F3 is synthesized by carbothermal reduction starting with stoichiometric amounts of NaF, Na2CO3, NH4H2PO4, V2O5, and acetylene black (flowing Ar, 350 °C for 8 h and 550—750 °C for 8 h).
ChemInform Abstract: [Sc2(μ‐OH)2(H2O)6 (NO3)2](NO3)2: Aqueous Synthesis and Characterization.
Authors: Wang Wei , Chang I‐Ya , Zakharov Lev , Cheong Paul Ha‐Yeon , Keszler Douglas A. 
Published: April 2013

AbstractThe title compound is synthesized in gram‐scale by addition of zinc metal powder to an aqueous solution of Sc(NO3)3(stirring, 24 h, 65% yield).
ChemInform Abstract: Enantioselective Heck Arylations of Acyclic Alkenyl Alcohols Using a Redox‐Relay Strategy.
Authors: Werner Erik W. , Mei Tian‐Sheng , Burckle Alexander J. , Sigman Matthew S. 
Published: April 2013

AbstractAn enantioselective variant of the Heck reaction that delivers β, γ, or δ‐aryl carbonyl products [cf.
ChemInform Abstract: Synthesis of Stable Acyclic Aminals Derived from L‐(+)‐Aspartic Acid and Their Application in Asymmetric Henry Reactions.
Authors: Koz Gamze , Astley Demet , Astley Stephen T. 
Published: April 2013

AbstractA series of stable acyclic aminals derived from L‐aspartic acid are synthesized and successfully applied as chiral ligands in the Cu(II)‐catalyzed Henry reaction of nitromethane with various aromatic aldehydes.
ChemInform Abstract: Combining Transition Metal Catalysis with Radical Chemistry: Dramatic Acceleration of Palladium‐Catalyzed C—H Arylation with Diaryliodonium Salts.
Authors: Neufeldt Sharon R. , Sanford Melanie S. 
Published: April 2013

AbstractA palladium‐catalyzed C—H arylation under extremely mild conditions is described.
ChemInform Abstract: An Efficient Synthesis of Symmetric and Unsymmetric Bis‐(β‐aminoamides) via Ugi Multicomponent Reaction.
Authors: La Spisa Fabio , Feo Alberto , Mossetti Riccardo , Tron Gian Cesare 
Published: April 2013

AbstractSymmetrical and unsymmetrical bis‐(β‐aminoamides) are prepared starting from symmetrical secondary diamines by using a double Ugi four‐component reaction.
ChemInform Abstract: Ruthenium‐Catalyzed Reductive Coupling of 1,3‐Enynes and Aldehydes by Transfer Hydrogenation: anti‐Diastereoselective Carbonyl Propargylation.
Authors: Geary Laina M. , Leung Joyce C. , Krische Michael J. 
Published: April 2013

AbstractGood levels of anti‐diastereoselectivity in propargylation of aliphatic aldehydes and enals are displayed by the presented ruthenium‐based catalyst system whereas the corresponding additions to aryl aldehydes remain unselective.
ChemInform Abstract: Synthesis of ortho‐Acylphenols Through the Palladium‐Catalyzed Ketone‐Directed Hydroxylation of Arenes.
Authors: Mo Fanyang , Trzepkowski Louis J. , Dong Guangbin 
Published: April 2013

AbstractThe title reaction provides various 2‐acylphenols by using the complementary methods A) and B), and an unusual ketal‐lactone [viz.
ChemInform Abstract: Enantioselective Nickel‐Catalyzed Hydrocyanation of Vinylarenes Using Chiral Phosphine—Phosphite Ligands and TMS‐CN as a Source of HCN.
Authors: Falk Anna , Goederz Anna‐Lena , Schmalz Hans‐Guenther 
Published: April 2013

AbstractThe absolute configuration of compound (IIIb) was determined to be (S) by chemical transformation to (S)‐(+)‐ibuprofen.
ChemInform Abstract: Copper Powder Catalyzed Direct Ring‐Opening Arylation of Benzazoles with Aryl Iodides in Polyethylene Glycol.
Authors: Yao Lifang , Zhou Qing , Han Wei , Wei Shaohua 
Published: April 2013

AbstractThis reaction yields aniline derivatives via ring opening of benzothiazoles or benzoxazoles, while thiazole and N‐methyl‐benzylimidazole do not react under these reaction conditions.
ChemInform Abstract: Rhenium‐Catalyzed Regio‐ and Stereoselective Synthesis of γ‐Thio‐α,β‐unsaturated Ketones via Insertion of Terminal Alkynes into the C—S Bond.
Authors: Nishi Mitsumi , Kuninobu Yoichiro , Takai Kazuhiko 
Published: April 2013

AbstractThis reaction is the first example of insertion of alkynes into a C—S bond of α‐thioketones affording the title compounds in good to high yields.
ChemInform Abstract: A Practical Isocyanide‐Based Multicomponent Synthesis of Polysubstituted Cyclopentenes.
Authors: Sagirli Akin , Dueruest Yasar , Kariuki Benson , Knight David W. 
Published: April 2013

AbstractPolysubstituted cyclopentene derivatives (IV), (VI) are obtained by multicomponent reaction of β‐nitrostyrene, benzylidenemalononitriles, and 2‐morpholinoethyl isocyanide in the absence of any catalyst.
ChemInform Abstract: NiO—SnO2 Composite Nano‐Powder: Preparation and Evaluation of Their Catalytic Activity in the Synthesis of 1‐Amidoalkyl‐2‐naphtholes.
Authors: Dehbashi Mohsen , Aliahmad Mousa , Shafiee Mohammad R. M. , Ghashang Majid 
Published: April 2013

AbstractNano‐powder of NiO—SnO2 is prepared and applied as an efficient catalyst for the three‐component reaction of 2‐naphthol with aromatic aldehydes and amides or ureas (III).
ChemInform Abstract: Gold Catalysis: Catalyst Oxidation State Dependent Dichotomy in the Cyclization of Furan—Yne Systems with Aromatic Tethers.
Authors: Hashmi A. Stephen K. , et al. et al. 
Published: April 2013

AbstractThis method yields either fluorene derivatives or 2‐furyl‐substituted indene derivatives depending on the applied gold catalyst.
ChemInform Abstract: Palladium‐Catalyzed Carbonylative Coupling of Aryl Iodides and Benzyl Acetylenes to 3‐Alkylidenefuran‐2‐ones under Mild Conditions and Its Density Functional Theory Modeling.
Authors: Wu Xiao‐Feng , Jiao Haijun , Neumann Helfried , Beller Matthias 
Published: April 2013

AbstractThis is a general and efficient method for the preparation of furan‐2‐ones and alkynones under mild conditions in good to excellent yields.
ChemInform Abstract: Water‐Soluble Chiral Ruthenium(II) Phenyloxazoline Complex: Reusable and Highly Enantioselective Catalyst for Intramolecular Cyclopropanation Reactions.
Authors: Abu‐Elfotoh Abdel‐Moneim , Nguyen Diem Phuong Thi , Chanthamath Soda , Phomkeona Kesiny , Shibatomi Kazutaka , Iwasa Seiji 
Published: April 2013

AbstractThe easy separation of the cyclopropyl product, the water‐soluble catalyst, and the simple reuse of the catalyst at least five times without significant decrease in reactivity are advantages of this method.
ChemInform Abstract: Water Control over the Chemoselectivity of a Ti/Ni Multimetallic System: Heck‐ or Reductive‐Type Cyclization Reactions of Alkyl Iodides.
Authors: Millan Alba , Alvarez de Cienfuegos Luis , Miguel Delia , Campana Araceli G. , Cuerva Juan M. 
Published: April 2013

AbstractIn the presence of water, different alkyl iodides undergo reductive radical cyclization.
ChemInform Abstract: Dual Nucleophilic/Electrophilic Capture of in situ Generated Iminium Ethers: Towards the Synthesis of Functionalized Amide Building Blocks.
Authors: Peng Bo , O'Donovan Daniel H. , Jurberg Igor D. , Maulide Nuno 
Published: April 2013

AbstractThe reaction proceeds via a cyclization followed by a Claisen rearrangement to yield iminium ether intermediates, which react with various nucleophiles.
ChemInform Abstract: From Alcohols to Indoles: A Tandem Ru Catalyzed Hydrogen‐Transfer Fischer Indole Synthesis.
Authors: Porcheddu Andrea , Mura Manuel G. , De Luca Lidia , Pizzetti Marianna , Taddei Maurizio 
Published: April 2013

AbstractA new version of the Fischer indole synthesis is presented which uses primary and secondary alcohols instead of aldehydes.
ChemInform Abstract: Potassium Iodide Catalyzed Simultaneous C3‐Formylation and N‐Aminomethylation of Indoles with 4‐Substituted‐N,N‐dimethylanilines.
Authors: Li Lan‐Tao , Li Hong‐Ying , Xing Li‐Juan , Wen Li‐Juan , Wang Peng , Wang Bin 
Published: April 2013

AbstractVarious functionalized indole derivatives are prepared by a new one‐pot process under mild reaction conditions.
ChemInform Abstract: Palladium‐Catalyzed Intramolecular C—H Amidation: Synthesis and Biological Activities of Indolobenzazocin‐8‐ones.
Authors: Boonya‐udtayan Sasiwadee , Eno Meredith , Ruchirawat Somsak , Mahidol Chulabhorn , Thasana Nopporn 
Published: April 2013

AbstractThe title compounds are evaluated for their cytotoxicity against four cancer cell lines.
ChemInform Abstract: Direct C‐3‐Arylations of 1H‐Indazoles.
Authors: Ben‐Yahia Ali , Naas Mohammed , El Kazzouli Said , Essassi El Mokhtar , Guillaumet Gerald 
Published: April 2013

AbstractThese are the first examples for intermolecular C—H arylation of 1‐substituted indazoles.
ChemInform Abstract: Reaction of 1‐Nitroso‐2‐naphthols with α‐Functionalized Ketones and Related Compounds: The Unexpected Formation of Decarbonylated 2‐Substituted Naphtho[1,2‐d][1,3]oxazoles.
Authors: Aljaar Nayyef , Malakar Chandi C. , Conrad Juergen , Frey Wolfgang , Beifuss Uwe 
Published: April 2013

AbstractThe title reaction of nitroso‐2‐naphthols works well with various α‐functionalized ketones and tolerates aryl and allyl bromides, α‐bromo diketones, cyanides, and ketoesters, as well as α‐bromoesters providing an efficient access to numerous annulated oxazoles.
ChemInform Abstract: Synthesis and Antioxidant Activity of a New Class of Mono‐ and Bis‐heterocycles.
Authors: Reddy Guda Mallikarjuna , Reddy Putta Ramachandra , Padmavathi Venkatapuram , Padmaja Adivireddy 
Published: April 2013

AbstractNovel highly functionalized mono‐ and bis‐heterocycles (VI)—(XI) are synthesized and tested for their antioxidant properties.