Miracle-dz/UniFAR-FTUs huggingface dataset:
Electricity generation from terephthalic acid using a microbial fuel cell

BACKGROUND: Pure terephthalic acid (PTA) is a petrochemical product of global importance and is widely applied as an important raw material in making polyester fiber and polyethylene terephthalate (PET) bottles. In this work, a single-chamber microbial fuel cell (MFC) was constructed using terephthalic acid (TA) with a chemical oxygen demand (COD) concentration range from 500 mg L−1 to 3500 mg L−1 as the electron donor and strain PA-18 as the biocatalyst. RESLUTS: In the single chamber MFC, several factors were examined to determine their effects on power output, including COD concentration and electrode spacing. The characteristic of the strain PA-18 was further studied. Cyclic voltammetry showed that electrons were directly transferred onto the anode by bacteria in biofilms, rather than self-produced mediators of bacteria in the solutions. Scanning electron microscopy (SEM) observation showed that the anodic electrode surface was covered by bacteria which were responsible for electron transfer. Direct 16s-rDNA analysis showed that the PA-18 bacteria shared 99% 16SrDNA sequence homology with Pseudomonas sp. CONCLUSIONS: Electricity generation from TA in MFC was observed for the first time. The maximum power density produced by TA was 160 mW m−2, lower than that achieved using domestic wastewater. This novel technology provided an economical route for electricity energy recovery in PTA wastewater treatment. High internal resistance was the major limitation. To further improve the power output, the electron transfer rate was accelerated by overexpression of membrane the protein gene of the strain PA-18 and by reducing the electrolyte and mass transfer resistance by optimizing reactor configuration. Copyright © 2008 Society of Chemical Industry
Stereoselective Reduction of 2‐Hydroxy Ketones towards syn‐ and anti‐1,2‐Diols

Stereoselective reduction of 2-hydroxy ketones should in principle give access to syn- and anti-1,2-diols. anti-1,2-Diols are accessible in a highly selective way using zinc borohydride [Zn(BH4)2] under chelation control (dr>20:1). Diastereoselective reduction of unprotected or even protected 2-hydroxy ketones towards syn-1,2-diols could be achieved only with moderate selectivity of dr≤5:1. Even when using sterically demanding protecting groups and/or polymer-supported borohydride reagents high selectivity could not be achieved. A new ionic liquid-dependent borohydride reduction method, although highly attractive with respect to reaction engineering, resulted in only moderate to good selectivity. An efficient two-step biocatalytic method for the synthesis of syn-1,2-diols is described. The method relies on the whole-cell Pichia glucozyma-catalyzed stereoselective reduction of the unprotected (R)-2-hydroxy ketones (dr>10:1). The latter are accessible through thiamine diphosphate-dependent enzyme-catalyzed synthesis starting from simple aldehydes. Thus, biocatalytic transformations enable a process which is hardly accessible through present non-enzymatic methods.
Fundamental limits on two-photon absorption cross sections

We apply sum rules to calculate the maximum limit of the resonant two-photon absorption cross section. Comparison of the theory with experimental data from the literature shows that no molecule ever measured exceeds this limit. Molecules with more π electrons have larger two-photon cross sections; but, the two-photon cross sections fall further below the fundamental limit as the number of electrons increases—implying that the additional electrons are not participating efficiently. The sum rules can aid in developing structure property relationships by providing metrics that lead to a deeper understanding of the available data.
Renormalization and scaling in the X-ray absorption and Kondo problems

The renormalization group method is extended in the case of logarithmic problems to include the imaginary parts of Green function and vertices which have been neglected in the earlier versions of the theory. The relationship between multiplicative renormalization absorption and Kondo problems. The properly defined invariant couplings depend on a single variable, the scaling energy, and are real, as expected physically. The scaling laws are rederived on this more rigorous basis. It is shown that the imaginary parts of the Green functions and vertices give no contribution to the scaling laws.
TDLAS for measurement of temperature in combustion environment

Tunable Diode Laser Absorption Spectroscopy (TDLAS) technique has many significant advantages such as non-intrusive compared with traditional combustion parameter measurement techniques. In this paper, according to the absorption lines optimization criterions, the 7444.352+7444.371 cm-1 and 7185.597 cm-1 line pair of water vapor (H2O) is selected for the temperature measurement of combustion environment in 900-1600K region, and two most important influencing factors (temperature and pressure) are analyzed by simulation of absorption spectrum based on HITRAN. Therefore, TDLAS system using the 7444.352+7444.371 cm-1 and 7185.597 cm-1 line pair based on Time-Division-multiplexing (TDM) strategy has been designed. This TDLAS system has been applied for the temperature measurement in the exhaust of Rocket Based Combined Cycle (RBCC) engine. Compared with the pressure measured by the pressure transducer in combustion chamber, the tendency of temperature measurement has well agreement with the pressure. The result of temperature measurement using TDLAS technique has great importance to the evaluation of RBCC combustion efficiency.
Environment-Dependent Tight-Binding Model for Molybdenum

A transferable orthogonal tight-binding model is developed for molybdenum, with special emphasis on applications in molecular-dynamics studies. The elements of the Hamiltonian matrix and the repulsive potential are allowed to depend on the environment in order to account for the effects of the neglected three-center matrix elements, for the neglected nonorthogonality effects and for the variation of the finite set of basis orbitals in different configurations as well. To check the accuracy of the model, the structural energy differences, the elastic constants, the phonon spectrum along high-symmetry lines in the Brillouin zone, the formation and migration energy of a vacancy, the formation energy of an octahedral interstitial atom, surface energies, and relaxations, as well as reconstructions of a (100) surface, are calculated and compared with ab initio data and experimental results.
A simple and efficient mechanochemical route for the synthesis of 2-aryl benzothiazoles and substituted benzimidazoles

An efficient and versatile mechanochemical route to 2-aryl benzothiazoles and both 2-substituted and 1,2-disubstituted benzimidazole derivatives has been developed via a simple mortar–pestle grinding method. The mechanochemical agitation was found to be sufficient for smooth condensation between a variety of aromatic aldehydes and o-aminothiophenol/o-phenylenediamine followed by cyclization leading to the formation of the corresponding 1,3-benzazoles. The salient features of this new protocol are catalyst-free reaction, cleaner reaction profiles, absence of a work-up step, high yields, and short reaction times.
Greenhouse gas emissions from soil under changing environmental conditions

Exchange of greenhouse gases (GHGs) between soils and the atmosphere is a natural consequence of several ecosystem processes (Schlesinger & Bernhardt, 2013). The balance of exchange contributes to the global atmospheric GHG budget, in which soils can act as either a net source or sink of GHGs. Key ecosystem processes participating in GHG uptake and emissions are plant photosynthesis (resulting in organic matter input to soils), plant respiration, animal and soil microbial respiration (both aerobic and anaerobic), fire and soil microbial transformations of nitrogen (N). There are also many human-induced transformations that create GHG emissions, either directly through burning of fossil fuels and industrial processing of mined natural resources or indirectly through land-use change, manipulation of natural processes through various management strategies, altering natural cycles of water and nutrients and changing energy flows. Humaninduced changes to the exchange of GHGs among plants, soils and the atmosphere are not limited to their effects on the atmospheric burden of GHGs: significant changes to the land surface of our planet itself have created challenges that require understanding of how a changing environment feeds back to affect GHG emissions (Richter et al., 2011). There is broad scientific consensus that global climate change is a consequence of increased anthropogenic GHG emissions (Anderegg et al., 2010). However, the way in which processes governing the exchange of GHGs between soils and the atmosphere are affected by environmental change remains under scientific debate. Understanding the dynamics and feedback mechanisms among components of the soil–plant–atmosphere continuum are essential, not only to improve the assessment of today ́s regional, national and global GHG inventories, but also to predict impacts of future climate conditions. A better understanding of the impact of land management approaches on the net balance of key GHG species, such as CO2, CH4 and N2O, is critical for our ability to guide mitigation and climate change adaptation strategies. This Thematic Section was assembled with contributions derived from a symposium on the topic at EUROSOIL 2012 in Bari, Italy (Franzluebbers & Senesi, 2012). Submissions were invited following the symposium to focus on recent developments and state-of-the-art measurements and modelling of biogeochemical processes, as well as mechanisms of GHG emissions at various scales. We encouraged the submission of studies on the turnover of carbon (C) and N with respect to the production and emission of GHGs from soils. We also encouraged papers on advances in methodological aspects on the separation of heterotrophic and autotrophic respiration and isotopic studies aiming to improve the understanding of transport or production of CO2, N2O and CH4.
Thin hydrocarbon and water films on bare and methylated silica: vapor adsorption, wettability, adhesion and surface forces.

The vapor adsorption of different n-alkanes, cyclohexane, toluene, and water on bare and methylated pyrogenic silica (Aerosil OX-50) has been studied gravimetrically. Linear adsorption isotherms of the n-alkanes and of cyclohexane on both substrates are found up to high relative vapor pressures; the same holds true for toluene on methylated silica. The linearity of the isotherms indicates relatively weak lateral interactions. On bare silica, the adsorption, expressed in mol/m 2 , of the n-alkanes studied (C7-C9) is independent of chain length. The adsorption strongly increases after the coverage, corresponding to a monolayer of alkanes oriented perpendicular to the surface has been reached. Methylation of the silica is found to decrease the adsorption of all the adsorptives studied. On methylated silica the octane isotherm lies below the coverage of a monolayer parallel to the surface until just before saturation. From the adsorption data, surface pressure isotherms are constructed, and the work of adhesion is obtained. The work of adhesion reveals that the Lifshits-van der Waals part of the silica surface tension is reduced from 44 mJ/m 2 for bare (pyrogenic) silica to 30 mJ/m 2 for methylated silica. The adsorption data are also converted to disjoining pressure isotherms. At small film thicknesses, the disjoining pressure can be described by an exponential short-range interaction
Outgassing Quantification Analysis of Extreme Ultraviolet Resists

Extreme ultraviolet (EUV) resist outgassing quantification analysis using the pressure rise method with a modified ideal gas equation is discussed. The use of the outgassing amounts based on the E0 and/or multiples of E0 is recommended as this information may be crucial in understanding the behavior of resist outgassing at various exposure or patterning doses. Furthermore, this method is effective in representing resist outgassing release mechanisms which were found to differ greatly depending on the resist formulation. Applying this method with quadrupole mass spectrometry (QMS), analysis of the resist outgassing obtained from a model poly(hydroxystyrene) (PHS) resist with varied quencher concentrations showed that the decrease and shift of the maximum pressure rise peak of the pressure rise curve as quencher concentration was increased was found to be due to the suppression of photo acid production which, in effect controls the amount of protecting group released as resist outgassing.
Impact of Boundary Conditions on the Reconstructed Flame Transfer Function for Gas Turbine Combustion Systems

In order to achieve low levels of pollutants modern gas turbine combustion systems operate in lean and premixed modes. However, under these conditions self-excited combustion oscillations due to a complex feedback mechanism between pressure and heat release fluctuations can be found. These instabilities may lead to uncontrolled high pressure amplitude oscillations which can damage the whole combustor. The flame induced acoustic source terms are still analytically not well described and are a major topic of thermo-acoustic investigations. For the analysis of thermo-acoustic phenomena in gas turbine combustion systems flame transfer functions can be utilized. The purpose of this paper is to introduce and to investigate modeling parameters, which could influence a novel computational approach to reconstruct flame transfer functions known as the CFD/SI method. The flame transfer function estimation is made by application of a system identification method based on Wiener-Hopf formulation. Varying acoustic boundary conditions, combustion models and time resolutions may strongly affect the reconstructed flame response characterizing overall system dynamics. The CFD/SI approach has been applied to a generic gas turbine burner to derive a flame response. 3D unsteady simulations excited with white noise have been performed and the reconstructed flame transfer functions have been validated with experimental data. Moreover, the impact on the reconstructed flame transfer functions because of different boundary condition configurations has been examined.Copyright © 2008 by ASME
Structure-Properties Relationships for Bisphenol A Polycyanurate Network Modified with Polyoxytetramethylene Glycol

A series of polycyanurate networks (PCNs), based on the dicyanate of bisphenol A monomer (DCBA), were synthesized in the presence of different contents of hydroxyl-terminated polyoxytetramethylene glycol (PTMG). The chemical structure, T g behaviour, modulus-composition relations and mechanical properties of the modified PCNs were investigated by Fourier transform infrared (FTIR) spectroscopy, dynamic mechanical thermal analysis (DMTA) and mechanical testing. The oligomer modifier influences the structure of the final networks insofar as it is partly incorporates and partly dissolves in the polycyanurate matrix, and, thus, decreases the final T g of these modified thermosets. All modified polycyanurate networks exhibit a single, broad glass transition that shifted to lower temperature as the modifier content was increased.
The role of aluminum in selective reactive ion etching of GaAs on AlGaAs

We have studied the role of aluminum in the formation of an etch barrier at the GaAs/ Alx Ga1−x As interface during reactive ion etching in CCl2 F2 plasma. The minimum Alx Ga1−x As thickness needed to form the barrier is Al mole fraction dependent and was determined with etching experiments monitored by optical emission spectroscopy. Effective Alx Ga1−x As layers for forming an etch barrier are 275 A for x=0.02, 22 A for x=0.10, 15 A for x=0.15, 12 A for x=0.20, and 9 A for x=0.30. For all Al mole fractions except x=0.02, these thicknesses correspond to a sheet dose equivalent to 3/4 of a monolayer of Al in the original Alx Ga1−x As layer. Barrier layers for x=0.02, 0.10, 0.25, and 0.30 were examined without air exposure by angle‐dependent x‐ray photoelectron spectroscopy. For samples that are not overetched, the surface is covered with ∼20 A of AlF3 intermixed with a gallium halide containing chlorine and fluorine and is depleted of arsenic. For substantially overetched barriers, a 30 A layer is formed w.
Gas and vapour movements in the soil: I. The diffusion of vapours through porous solids

The dependence of the coefficient of diffusion, D, upon the porosity, S, of a granular solid is investigated experimentally. For steady state conditions, using carbon disulphide and acetone vapours, it is shown that a curve connecting D/D0 and S can be drawn which is independent of the nature of the solid, its moisture content and, within limits, its texture. For a limited range of values of S (0·0 < S < 0·7) a good approximation is D/D0 = 0·66S and over this range the diffusion coefficients are larger than those found by Buckingham for carbon dioxide. Investigation of the non-steady state shows that in soils the attainment of pressure equilibrium is retarded by adsorption, and it is suggested that Buckingham's low values for steady-state conditions can be attributed to premature observations of the diffusion rates; the steady state had probably not been attained when his measurements were made.
CHANGES WITH TIME IN SOIL BIOMASS C, N AND P OF MINE SPOILS IN A DRY TROPICAL ENVIRONMENT

Soil biomass C, N and P were determined for a native forest site, an unmined deforested site and an age-series of adjacent coal mine spoils (5, 10, 12, 16 and 20 yr). Biomass C ranged from 209 to 867 μg g−1 soil, biomass N from 20 to 75 μg g−1 soil and biomass P from 7 to 29 μg g−1 soil. Biomass C, N and P were linearly related to each other. Biomass C was also related to the root biomass. Biomass N with a mean C:N ratio of 11.8 accounted for 2.2–4.2% of the total soil N and was positively related to the mineral N of soil. Biomass C:P ratio ranged from 27.6 to 31.0%. The biomass P was significantly related to the bicarbonate soluble soil Pi. Soil microbial biomass was characterized by a mean C:N:P ratio of 29:3:1. Soil microbial C, N and P were positively related with the age of mine spoils, the values for the youngest spoil (5 yr old) being about four times lower compared to native forest soil. Total soil N was also positively related with age of spoil. The data suggest that microbial biomass can be take.
1H‐nuclear magnetic resonance study of a soil humic acid

Summary The structure of a humic acid from a New Zealand pasture topsoil has been investigated by 1H-n.m. r. spectroscopy. The work complements a recent 13C-n.m. r. study on the same humic acid. Irradiating the water peak in the spectrum greatly improves spectral quality. The results show that the proton aromaticity of the humic acid (excluding exchangeable protons) is 17%. Considerable amounts of protons in the humic acid are associated with carbohydrates (35%). Useful structural parameters describing the average molecular structure of the humic acid were derived by combining both 1H and 13C data. Further work is needed to determine both the percentage exchange of protons in alkali and the percentage of inorganic hydrogen in humic acids, before the condensation and the degree of substitution of aromatic rings can be quantitatively estimated.
Homodesmotic reactions for the assessment of stabilization energies in benzenoid and other conjugated cyclic hydrocarbons

New homodesmotic reactions are designed that provide and alternative basis for evaluating stabilization energies of benzenoid and other conjugated cyclic hydrocarbons. As in previous cases, carbon–carbon bonds are matched in the sense of having equal numbers of Csp2–Csp2, Csp2Csp2, Csp2–Csp3, etc. bonds in reactants and products, while simultaneously the various carbon–hydrogen bonds are matched as closely as possible. By minimizing extraneous energy contributions to the reaction heat arising from changes in hybridization and C–H binding, such reactions single out those structural features resulting in stabilization. These new reactions have the advantage that experimental ΔHf° data is currently available for the necessary reactant molecules, thus allowing an explict evaluation of the homodesmotic stablization energy to be made, which is compared to quantum theoretical calculations wherever possible.
Investigation of surface properties of ultrafine particles by application of a multistep condensation nucleus counter

The fate of atmospheric ultrafine particles is determined by their size, chemical composition, and especially by their physical and chemical surface properties. To characterize the surface of ultrafine particles, their behavior as condensation nuclei can be used. Monodisperse ultra-fine particles with different surface structures were investigated by observing the onset of droplet formation at a fixed electrical mobility diameter. Droplet growth was detected by application of a multistep condensation nucleus counter (CNC). The particles were generated under well-controlled conditions and monodisperse fractions were obtained using an electrostatic classifier. For studying the influence of changes in the surface structure, ultrafine sulfuric acid droplets were coated with different organic materials. Different surface films required different supersaturations for droplet growth depending on the molecular structure and layer thickness of the material used for coating. Therefore it was concluded that certain .
Electrochromic properties of vanadium oxide thin films prepared by PSPT: Effect of substrate temperature

Electrochromic vanadium oxide (V2O5) thin films were deposited onto glass and fluorine doped tin oxide (FTO) coated glass substrates from methanolic vanadium chloride solution by pulsed spray pyrolysis technique (PSPT). The films were synthesized at different substrate temperatures ranging from 350°C-450°C with a temperature step of 50°C. The structural, morphological, optical and electrochromic properties of the synthesized films were investigated. The films were polycrystalline with tetragonal crystal structure. Scanning electron microscopy reveals compact morphology at high temperature. All films exhibited cathodic electrochromism in lithium containing electrolyte (0.5 M LiClO4 + Propylene Carbonate). Maximum coloration efficiency (CE) 15.16 cm2C−1, was observed for the films deposited at 350°C.
Microwave spectrum and molecular structure of the HSC radical

The HSC radical, that is a geometrical isomer of the HCS radical, has been identified and characterized by microwave spectroscopy. The HSC radical has been produced in a discharge plasma of a gaseous mixture of H2S and CO, and its rotational spectral lines are observed with a source-modulation spectrometer and a Fourier-transform millimeter-wave spectrometer. The spectrum of the deuterated species, DSC, has also been measured with a source-modulation spectrometer. Rotational constants, centrifugal distortion constants, and spin–rotation interaction constants with their centrifugal distortion corrections for HSC and DSC are determined from the observed transition frequencies by a least-squares method. Furthermore hyperfine interaction constants of the hydrogen nucleus are also determined for HSC. The Fermi contact term of the hydrogen nucleus takes a large positive value, 288.845±0.185 MHz, which indicates that the HSC radical is a σ radical (2A′) in the ground electronic state. The harmonic force field is.