Miracle-dz/UniFAR-FTUs huggingface dataset:
Improvement of polypyrrole and carbon nanotube co‐deposition techniques for high charge‐transfer electrodes

Both carbon nanotubes (CNTs) and polypyrrole (PPy) have been investigated as materials for manufacturing high charge‐transfer electrodes due to their outstanding performances. The combination of their complementary properties via an electrochemical co‐deposition route has been already shown to achieve interesting results. In this work, PPy and chemically‐functionalized multi walled CNTs (COOH‐MWCNT) were potentiostatically, galvanostatically and potentiodynamically electrodeposited from an aqueous solution to form a nanocomposite on the surface of a variety of metal electrodes. A study of the influence of experimental parameters such as temperature, current, and growth rate in the different electrodeposition methods was performed. The electronic and electrochemical properties of the nanocomposite films have been studied by cyclic voltammetry and electrochemical impedance spectroscopy, while a morphological study has been performed via scanning electron microscopy. A comparison between the different techniques and guidelines for best results will be reported.
Lawrence Berkeley Laboratory UNIVERSITY OF CALIFORNIA ENERGY & ENVIRONMENT DIVISION Polar Organic Matter in Airborne Particles: Chemical Characterization and Mutagenic Activity

Polar organic matter (extracted from inhalable particles collected in Elizabeth NJ and National Institute of Standards and Technology Standard Reference Material SRM 1649) has been characterized by determining elemental and ionic composition, chemical classes and mutagenic activity. The acetone extracts of SRM1649 and Elizabeth NJ samples were 46 and 40% carbon, respectively. When compared to the NJ extract, the SRM extract was enriched in aldehydes and ketones and deficient in carboxylic acids. Significant amounts of organic nitrogen were found in both extracts. Infrared spectra and class tests suggested the presence of nitro compounds, organic nitrates or nitrites, amines, and amides. Fluorescence suggested the presence of aromatic species. For SRM 1649 the acetone extracts accounted for 36% (-S9) and 40% (+S9) of the mutagenic a~tivity in the Ames assay with TA98 (specific mutagenic activity) The acetone extract of SRM 1649 had about four times greater than that from the NJ particles. Both extracts showed . substantial decreases in mutagenic activity when tested with nitroreductase-deficient strains of T A98. A simple resolubilization of the NJ extract concentrated the biologically active components into the least polar of three fractions. of the unfractionated Elizabeth acetone extract, alone and while mixed with 100 microliter standard solutions at each concentration. The three standard solutions were analyzed at the same time, for a total of nine spots per class. Spot tests were carried out in a glazed white porcelain spot test plate or in 8 ml glass vials. Extracts of blank filters were also analyzed. Sensitivity was estimated from results for aliquots of standard compounds at 1, 10 and 100 microgram per test. For the SRM 1649 acetone extract, amounts used for each test varied from 50 to 180 micrograms, as indicated below. Not all tests were performed on the SRM extract.
Alkylated hyperbranched polymers as molecular nanosponges for the purification of water from polycyclic aromatic hydrocarbons

A series of hyperbranched polymers functionalized with long aliphatic chains has been prepared and characterized. The property of films prepared from these polymers to encapsulate lipophilic polyaromatic pollutants dissolved in water has been established. The level of pyrene and fluoranthene remaining in water after treatment ranged from 1 to 30 ppb for most of the hyperbranched polymers, while for the relatively more water-soluble phenanthrene a final concentration of about 50 to 70 ppb could be attained. The inclusion formation constants determined for the polycyclic aromatics were 2.0 × 108–6.3 × 106 M−1 for pyrene, 1.2 × 107–1.6 × 106 M−1 for fluoranthene, and 3.8 × 106–4 × 105 M−1 for phenanthrene. The loading capacities depend on the nature of the polycyclic aromatic compounds and the chemical structure of the parent hyperbranched polymers, ranging from 6 to 31 mg/g of polymer for fluoranthene, 15–54 mg/g for phenanthrene, and 6–35 mg/g for pyrene. Regeneration of the absorbing films was achieved by their treatment with acetonitrile. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2299–2305, 2005
Ripening of cellular latex films

Cellular films have been produced through evaporation of aqueous dispersions containing latex particles. The membranes of the cells are made of hydrophilic species which originate from the surfaces of the particles; they form a periodic structure which separates the cell cores from each other. Thermal treatments have been applied to induce the fragmentation of membranes. The resulting structural changes have been observed through SANS and electron microscopy. It has been found that the fragmentation of membranes is controlled by three parameters: the mobility of membrane polymers, the anchoring of these polymers on the core and the mobility of the core
Novel anion-exchange organic-inorganic hybrid membranes prepared through sol-gel reaction and UV/thermal curing

Anion-exchange organic-inorganic hybrid membranes were prepared through sol-gel reaction and UV/thermal curing of positively charged alkoxysilane and the alkoxysilane containing acrylate or epoxy groups. Properties of prepared hybrid membranes were varied by control of the molar ratio of the precursors. It was shown that the thermal degradation temperatures (Td) of the membranes were in the range of 212–226°C, water uptakes in the range of 9.6–14.6% and IEC values in the range of 0.9–1.6 mmol g−1. The hybrid membranes show high permeability to anions, as reflected by the high static transport number (t−) of the anion (Cl−). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008
Suppression of Cobalt Dissolution from the LiCoO2 Cathodes with Various Metal-Oxide Coatings

ZrO 2 -coated LiCoO 2 showed negligible capacity loss up to 70 cycles at the cutoff voltage of 4.4 V, while bare LiCoO 2 exhibited ∼60% of its original capacity after only 30 cycles. The improved electrochemical behavior was caused by the suppression of cobalt dissolution by nanoscale metal-oxide coating. The amount of cobalt dissolution in the electrolyte from the charged LiCoO 2 held at 25 and 90°C, respectively, correlates well with the capacity retention, among coatings of various metal oxides. The trend of the open-circuit voltage reduction is again well correlated with both the cobalt dissolution and capacity retention.
Synthesis, spectral, thermal and NLO properties of N,N ‐Dimethyl anilinium picrate

The crystalline substance N,N ‐dimethyl anilinium picrate(DMAP) was synthesized and the single crystals of the title compound were grown by slow evaporation solution growth technique at room temperature. The crystalline nature of the material has been confirmed by powder X‐ray diffraction method. The elemental analysis data confirm the stoichiometry and hence the molecular formula of the synthesized material. The formation of the charge‐transfer complex has been confirmed by UV‐visible spectral data. The infrared and 1H NMR spectroscopic data indicate a charge transfer activity associated with a proton transfer from the acceptor to the donor followed by intermolecular hydrogen bonding. Thermal behavior and stability of crystal were studied using thermo gravimetric (TG) and differential thermal analyses (DTA) techniques. The second harmonic generation (SHG) of the material was confirmed using Nd: YAG laser. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Removal of aromatic amines and decolourisation of azo dye baths by electrochemical treatment

The presence of aromatic amines in effluent from dyeing processes of the textile industry is an added problem to the high coloration typical of this type of effluent. The main objective of the present work was to eliminate these two problems simultaneously by electrochemical treatment using bath solutions containing three azo dyes. For the analysis of amines, a liquid–liquid extraction method was developed as an easier and faster alternative to the method described in the standards and widely used in analytical laboratories. Four amines (aniline, o-toluidine, 4-chloroaniline and 4-aminobiphenyl) were detected by GC-MS in the residual azo dye baths. A total amine concentration of between 2.5 and 1 ppm was detected, 4-aminobiphenyl being the main compound. Both residual colour and amines were removed by electrochemical treatment carried out at three current densities (3, 24 and 40 mA/cm2). At 24 mA/cm2, more than 90% of colour removal was achieved, and the total amine concentration was reduced to below 0.15 ppm.
Inactivation of Microorganisms in Tyvek ® Packaging by Microwave Plasma Processed Air

Plasma is well-known for its antimicrobial capacity and moreover, it is successfully used in manifold industrial fields such as packaging industry. Microwave plasma processed gas with shares of reactive nitrogen species (RNS) was investigated for its decontamination efficiency against vegetative bacteria, conidia and bacterial endospores packed in Tyvek ® . For all tested microorganisms, increased inactivation was found at prolonged treatment times. Furthermore, a treatment with moistened gas resulted in shorter treatment times and a dependency of humidity was observed. The inactivation rates increased up to 6 log10 steps. The microwave plasma processed gas showed very high microbial effects to vegetative bacteria, spores of Bacillus atrophaeus and Aspergillus brasiliensis in treatment times comparable to currently common methods like EO, FORM and hydrogen peroxide. Moreover, this new methode is charaterized by advantages like no thermal influences, no toxicity for human and environment and low costs.
Study of Diffusion Instability in Ternary Gas Mixtures under Nonisothermal Conditions

The main objective of this article is to investigate the effect of heating (from below or above) on stability of mechanical equilibrium in binary and ternary gas mixtures. Three series of experiments on instabilities in are reported gaseous diffusion. In one series occurrence of convective flows under diffusive mixing are investigated in the systems N2O . The temperature difference when the transition between the diffusion and the convective processes happen is higher at the bottom arrangement of N2O. In the second series the influence of temperature difference are studied in the mixture ! "! #"$$$#! $$$%# ! #& '# $#$ ! "! #"$$$#$(##$&$ )*+*), " (-# $%$" #$#& %$ -! $$ ! $$ %# ) . #/ ##%"% Linear stability theory is applied to determine the boundary of transition from the state of diffusion to the region of convection. The results of numerical study are in good agreement with the experiments.
Effects of Organized Media on the Excited-State Intramolecular Proton Transfer of 10-Hydroxybenzo[h]quinoline

Absorbance and fluorescence characteristics of 10-hydroxybenzo[h]quinoline (HBQ) are studied in the presence of {alpha}-, {beta}-, and {gamma}-cyclodextrins, and the surfactants, hexadecyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS), and polyoxyethylene(23) lauryl ether (Brij 35). Fluorescence measurements are used to investigate the effect of organized media on the excited-state intramolecular proton transfer (ESIPT) reaction of HBQ by monitoring the large Stokes-shifted tautomer emission. Absorbance measurements are used to further characterize the interactions of HBQ with the various media. 38 refs., 9 figs., 1 tab.
Analysis of temporal and spatial variability of total column ozone over West Africa using daily TOMS measurements

The aim of this study was to examine the temporal and spatial total column ozone distribution in West Africa using Total Ozone Mapping spectrometer (TOMS) daily data for five years between 2001 and 2005 in fifteen locations. In this study, certain significant observations emerged: weather activity particularly the rainfall producing mechanism (dynamic of the wind systems) was responsible for about 62% ozone distribution in the region. Ozone maximum and minimum concentrations over all the stations were 305 DU and 232 DU respectively producing an average range of 73 DU (only about 27.03% of the mean value). Ozone has a seasonal distribution with minimum occurring during the dry season and maximum occurring during the wet season. A decreasing rate of about –0.6 DU/year was found for the region. Interannual ozone characteristics revealed an oscillating feature similar to Quasi – biennial Oscillation (QBO) footprints which indicated the importance of stratosphere – troposphere exchange to ozone distribution in the region. Furthermore, lag of about one or two months occurs between south (lower latitude) and north (higher latitude) monthly ozone maximums.
Parallel‐beam X‐ray diffractometry using X‐ray guide tubes

A parallel-beam X-ray diffraction geometry using X-ray guide tubes is proposed to eliminate preferred-orientation effects in powder X-ray diffraction (XRD) patterns and for new applications of XRD. A bundle of X-ray guide tubes (polycapillaries) is used to provide an intense quasi-parallel (approximately 0.2° divergence) and large-diameter (approximately 20 mm) beam of X-rays needed for parallel-beam diffractometry. Mica and silicon particles were agitated inside a cylindrical chamber by a steady flow of N2 gas so that they were randomly oriented. The quasi-parallel incident X-ray beam passed through the cloud of floating particles. The diffracted X-rays were detected using a standard 2θ diffractometer. The integrated intensities observed agree well with those calculated from the known model of the crystal structure. This result demonstrates that this type of diffractometry is capable of avoiding preferred-orientation effects and of collecting XRD data for moving powder samples.
Rapid thermal N2O oxynitride on Si(100)

High‐resolution x‐ray photoelectron spectroscopy (XPS) in conjunction with secondary‐ion‐mass spectrometry was used to study the chemical nature and distribution of N in oxynitride films formed by rapid thermal N2O processes (RTPs) or conventional furnace methods. The kinetics of furnace oxide growth in N2O are slower than that in O2. During reoxidation the oxidation rate increased to that in pure O2 and the N in the SiO2–Si interface region is displaced into the bulk of the oxide. High‐resolution synchrotron Si 2p core‐level photoemission spectroscopy (PES) was used to study the oxide–Si(100) interface suboxide structures produced by RTP with and without the presence of N. XPS N 1s studies indicated that there are two types of N in the RTP oxynitride films. The chemical bond configuration of the first type of N is similar to that of N in Si3N4 and is mainly distributed within the first 1 nm from the interface. The second type of N is distributed mainly outside of the first 1 nm region, and the N is likel.
Aggregate stability and assessment of soil crustability and erodibility: I. Theory and methodology

Summary Crusting and erosion of cultivated soils result from aggregate breakdown and the detachment of soil fragments by rain, and the susceptibility of soil to these processes is often inferred from measurements of aggregate stability. Here, theories of aggregate breakdown are reviewed and four main mechanisms (i.e. slaking, breakdown by differential swelling, mechanical breakdown by raindrop impact and physico–chemical dispersion) are defined. Their relative importance depends on the nature of the rain, as well as on the soil's physical and chemical properties. The relations between aggregate breakdown, crusting and water erosion are analysed, and existing methods for the assessment of aggregate stability are reviewed. A unified framework for the measurement of aggregate stability is proposed to assess a soil's susceptibility to crusting and erosion. It combines three treatments having various wetting conditions and energies (fast wetting, slow wetting, and stirring after pre-wetting) and measures the resulting fragment size distribution after each treatment. It is designed to compare different soils, or different climatic conditions for a given soil, not to compare time-dependent changes in that soil.
Effect of rice straw on the composition of volatile soil gas and micro flora in the tropical paddy field

Abstract The effect of rice straw on the composition of volatile soil gas and microflora in the tropical paddy field was studied with and without fertilizer application. The volatile soil gas most abundantly found in plots with rice straw was methane followed by other gases, nitrogen, oxygen and carbon dioxide during the early stage of rice growth, while nitrogen predominated in later stages. The loss of soil nitrogen through volatilization increased following phosphorus application as well as rice straw application as compared with that in the control plot. In the former case, the enhancement of decomposition of organic-N was assumed to be due to the increase in population of cellulose decomposer. Rice straw application with or without N-fertilizer increased methane gas formation by 27 to 63 times as compared with the phosphorus plot and the peak of its formation was found 5 to 7 weeks after rice straw application. However methane formation in the control plot was very low and was found only 5 to 9 weeks.
Analysis of the Impact of Individual Glass Constituents on Electrocatalysis on Pt Electrodes in Alkaline Solution

In the previous paper [ibid., P1 (2008)] the authors reported on the impact of glass corrosion on establishing the electrocatalytic activity of fuel cell catalysts. The leaching of glass constituents into the electrolyte is responsible for insufficiently reproducible measurements of the oxygen redn. reaction as well as the hydrogen oxidn. reaction on polycryst. Pt. The authors elucidate which glass constituents are leached into the electrolyte through the anal. of alk. electrolytes in contact with Duran glass by inductively coupled plasma optical emission spectroscopy. By adding these constituents, i.e., silicates, borates, aluminates, and lead, sep. to the electrolyte, the authors evaluate their individual impact on electrocatalytic measurements. The results presented in this study help to explain the effects seen in measurements in alk. electrolyte with glass cells. [on SciFinder(R)]
Molecular Modeling Studies of RNA Polymerase II Inhibitors as Potential Anticancer Agents

Global physicochemical descriptor based QSAR models were developed using multiple linear regression (MLR) and partial least squares (PLS) for a set of 44 molecules as Derivatives of Oncrasin-1synthesized against cancer. Leave out one row method is used to validate the developed model. The MLR and PLS generated excellent models with good predictive ability and all the statistical values, such as r, r 2 , r 2 cv, r 2 ( test set), F and S values were 0.88, 0.78, 0.77, 0.77, 30.75 and 0.40 for MLR and r 2 cv, r 2 (test set) and statistical significance value were 0.77, 0.77 and 0.92 for PLS respectively, were satisfactory. The results obtained from this study provides insights regarding role of Bond dipole moment (subst. 2), Balaban topological index (whole molecule), First Atom E- state index (subst. 1) and VAMP heat of formation (Whole molecule) in determining the RNA polymerase II inhibitory activity. The results clearly reveal that the anti-cancer activity.
Fabrication of pit-structured ZnO nanorods and their enhanced photocatalytic performance

ZnO nanorods have been successfully prepared at low temperature (60 °C) in the presence of ammonia via a simple aqueous solution-based chemical approach. After calcination at 300 °C, many unique pitted structures are found on the surface of ZnO nanorods, although the shape and size of ZnO nanorods have almost no changes. Furthermore, the pit-structured ZnO nanorods exhibit higher photocatalytic activity for methylene blue photodegradation with a rate constant (k) of 0.01402 min−1, which is about 3 times more than that of uncalcined sample. The formation of the pitted structures is presumably attributed to the decomposition of a trace amount of ZnO(NH3)n complex implanted into ZnO crystals. In addition, a photocatalytic mechanism is proposed to explain the enhanced photocatalytic activity of the pit-structured ZnO nanorods.
A highly stable short α-helix constrained by a main-chain hydrogen-bond surrogate

Herein we describe a strategy for the preparation of artificial α-helices involving replacement of one of the main-chain hydrogen bonds with a covalent linkage. To mimic the CO···H−N hydrogen bond as closely as possible, we envisioned a covalent bond of the type CX−Y−N, where X and Y are two carbon atoms connected through an olefin metathesis reaction. Our results demonstrate that the replacement of a hydrogen bond between the i and i + 4 residues at the N-terminus of a short peptide with a carbon−carbon bond results in a highly stable constrained α-helix at physiological conditions as indicated by CD and NMR spectroscopies. The advantage of this strategy is that it allows access to short α-helices with strict preservation of molecular recognition surfaces required for biomolecular interactions.
Analytical and numerical studies of one-dimensional Poisson-Nernst-Planck models for ion channels

Ion channels are a group of transmembrane proteins that allow passage of ions from one side of the membrane to the other. The physiological event of ion transport is modeled by the Poisson-Nernst-Planck (PNP) system. We study the PNP system in presence of two or three types of ions with certain regions of the inside surface of the channel containing permanently charged amino acid side chains. A singular parameter e , related to the Debye length, is presented in the PNP system. In the case of two ions, the boundary conditions for the charged region can be specifically solved by solving a scaled algebraic equation. These conditions are then used to solve the PNP system numerically. Multiple solutions emerge from the computation and are probably indicative of more complex functions of ion channels. For ion channels baring three types of ions, the analytical equations are more complicated but the system can be solved using numerical approaches and examples of these results are presented in this paper. The PNP system contains information of the current-voltage (I-V) relations of ion channels when reaching steady-state. Analysis of the I-V property is shown and some representative results discussed.
Luminescence of excitons and Eu2+vc– centres in KI:Eu2+ crystals

Luminescence characteristics of KI:Eu2+ crystals are studied at 11.5–300 K under excitation in the 3.0–6.3 eV energy range. Besides the known 2.88 eV emission of Eu2+vc– centers, the new emission bands peaking at ∼3.75 eV, ∼3.3 eV, 3.06 eV, and 2.38 eV are found. The bands, located in the 3.1–4.3 eV energy range and strongly distorted due to their overlap with the Eu2+vc– absorption bands, are ascribed to the self‐trapped exciton emission. The 3.06 eV and 2.88 eV bands are ascribed to the electronic transitions from two close levels of the splitted T2g excited state of an Eu2+ ion. The 2.38 eV emission is ascribed to the radiative decay of an exciton localized near an Eu2+ ion. It is assumed that the appearance of the self‐trapped exciton emission under excitation in the Eu2+‐related absorption bands is connected with the radiative decay of excitons, which are formed at the recombination of electrons and holes, produced in the crystal as a result of the photostimulated charge transfer from the Eu2+‐perturbed I– states. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)