Miracle-dz/UniFAR-FTUs huggingface dataset:
Semiconducting Behavior of Organic Polymer Coating during its Degradation in 5‰ Sulfuric Acid Solution

In this paper, the semiconducting behavior of No.20 carbon steel coated with different polymer coating in 5‰ sulfuric acid solution was studied by utilizing potential-capacitance and Mott-Schottky analysis. It showed that in the same testing condition, the phenol aldehyde resin and epoxy resin showed n-type semiconducting behavior in 5‰ sulfuric acid, whereas for the alkyd resin, it showed p-type semiconducting behavior in 5‰ sulfuric acid solution. It was suggested that the space charge layer of the polymer coating in 5‰ sulfuric acid solution might be asymmetry. It was suggested that at the early stage of immersion, the polymer coating behaved as an insulator, with increasing immersion time, the coating transferred to P-type semiconductor, then to N-type semiconductor.
Iron complexes with gallic acid: a computational study on coordination compounds of interest for the preservation of cultural heritage

The electronic structures of iron coordination compounds [FeL4H12]−, [FeL4H12]2−, [Fe3L8H22]−, and [Fe3L8H22]2− (H4L = gallic acid, 3,4,5-trihydroxybenzoic acid) have been studied by density functional theory calculations, together with the 1-D periodic complex [Fe3L6H15]∞. Data regarding the ground-state spin multiplicities of these models for iron gall inks, the charge and spin distributions, the oxidation states of the metal centers, and the oxidizing potentials of the complexes have been computed. The absorption properties of these compounds have been related to the electronic structure of the coordinated ligands.
Evaluation of Dosage Forms: Studies on Commercial Tablet Dosage Forms of Naproxen

Studies on commercial tablets of naproxen were carried out to establish the feasibility of a dissolution-dialysis technique for the in-vitro evaluation of dosage forms. Disintegration time and dissolution parameters failed to give true indication of bioavailability. However, there was an excellent correlation between the dialysis rate constant and the pharmacokinetic parameters derived from bioavailability studies in man. The results demonstrate the usefulness of the dialysis rate constant over conventional dissolution methods for the in-vitro evaluation of naproxen tablets.
Valence‐band x‐ray photoelectron spectroscopic studies of manganese and its oxides interpreted by cluster and band structure calculations

Valence‐band and core‐level x‐ray photoelectron spectroscopy (XPS) of manganese and its oxides is reported and the valence‐band spectra are interpreted by various calculation models. The focus of this paper is on the valence band, which shows significant differences between the oxides of manganese in the formal oxidation states II, II/III, III, IV, VI and VII. The study reports the valence band for the metal and the following oxidized forms of the metal: MnO, Mn3O4, Mn2O3, MnO2, K2MnO4 and KMnO4. The difference seen in the valence‐band region makes this region appropriate for the surface analysis of manganese compounds and complements the core region, which is often complicated by broad peaks with satellite features. The valence‐band region is interpreted by band structure and cluster calculations. It is shown that the differences between the observed spectra and band structure calculations for Mn3O4, Mn2O3 and MnO2 may be a result of the calculation method and not of the highly intense satellites. Copyright © 2002 John Wiley & Sons, Ltd.
Caractérisation des canaux potassiques du tubule contourné proximal et des propriétés régulatrices des canaux chlorure de la membrane basolatérale des cellules intercalaires du tubule connecteur

Un canal chlorure de 10 pS de la membrane basolaterale des cellules intercalaires du canal connecteur presente des proprietes proches de celles de ClC-K2. Nos donnees de patch clamp montrent que son activite et le nombre de canaux actifs (N) augmentent avec (i) la depolarisation membranaire (ii) la concentration en calcium externe et (iii) l’alcalinisation extra et intracellulaire. L’alcalinisation extracellulaire deplace la dependance au voltage vers des potentiels negatifs, alors que l’alcalinisation intracellulaire augmente leur activite a des potentiels negatifs. Ces donnees suggerent que le Ca2+ extracellulaire et le pH modulent l’activite des canaux ClC-K2 via une action sur la porte commune plutot que sur les protopores des autres canaux ClC. Nous avons cherche a etablir le role et l’identite moleculaire des canaux potassiques basolateraux du tubule contourne proximal (PCT), peu connus. Nos resultats montrent la presence d’ARNm codant pour les sous-unites Kir4.2 et Kir5.1 dans le PCT et, par western blot et par immunohistochimie, leur expression sur la membrane basolaterale du PCT. Un canal potassique, etudie par patch-clamp, presente des proprietes semblables a celles des canaux heterotetrameriques Kir4.2/Kir5.1 sur la membrane basolaterale du PCT de souris : il presente une conductance de 47 pS, une rectification entrante induite par le Mg2+ intracellulaire, une dependance de son activite au pHi et un blocage par le Ba2+ extracellulaire. Cependant, un phenotype renal chez des souris invalidees pour le gene Kcnj15 codant pour Kir4.2 n’a pas pu etre mis en evidence.
Effects of Surface Chemistry on the Porous Structure of Coal

In this report, 129 Xe nuclear magnetic resonance spectroscopy of xenon gas adsorbed in coal is used to describe some poorly understood features of coal microporous structure, particularly in establishing that a connected network exists, the type of connectivity, and its changes with the rank of coal. Micropore size scale and distribution are also considered. Two methods are developed which are new and versatile tools for the investigation of porous structure. Both utilize xenon gas that is in motion, while undergoing diffusion or exchange in coal, to describe the connectivity of the micropore structure of coal. Time tracking of the adsorption process by NMR, selective saturation, and saturation transfer techniques were used to obtain new information on the coal rank dependence of porous structure. In addition, an existing 129 Xe chemical shift-pore diameter model was used to calculate micropore diameters for coals, as well as for a microporous carbon, before and after pore-size alteration. In the initial study performed, straightforward 129 Xe NMR spectra at equilibrium xenon adsorption at a series of pressures were acquired for a rank-varied set of six coals. Acquisition of the NMR signal as an echo was tested and found to improve spectral quality. The spectra were used to calculate micropore diameters for the six coals. These range from 5.6 to 7.5 � and exhibit a minimum value for the intermediate coal rank. The smallest pores occur in coals of about 82-85% carbon; at both lower and higher coal ranks, the average micropore size tends to be larger. The changes in the spectra with coal rank and surface area were explored. Signal linewidths were found to decrease with increasing coal rank and were interpreted in terms of increasing chemical or physical homogeneity of the coal as rank increases. The packing density of powdered coal was found to alter the spectral appearance in a high volatile bituminous coal, which is preliminary evidence that exchange affects the chemical shift of xenon in this coal.
Total Internal Reflection Fluorescence (TIRF) Microscopy

TIRF microscopy is a technique for imaging the surface of cells that utilizes a thin field of illumination to image fluorophores on or near to the coverslip. TIRF is a highly sensitive widefield camera-based technique providing an excellent signal-to-noise ratio compared with epi-fluorescence or confocal imaging methods. TIRF can be used alone or in combination with other imaging techniques to give an “inside and out” view of a specimen. This technical note describes the theoretical basis of TIRF microscopy, the hardware required and examples of TIRF applications.
Enzyme-analogue built polymers, 22. Influence of the nature of the crosslinking agent on the performance of imprinted polymers in racemic resolution†

The effect of the nature of the crosslinking agents in template-imprinted polymers on the selectivity during racemic resolution was investigated. Ethylene dimethacrylate was found to be the best crosslinking agent. The highest selectivity was achieved with polymers which have been prepared with 70-95% crosslinking agent in the monomeric mixture. A new optically active crosslinking agent, 1,4;3,6-dianhydro-D-sorbitol 2,5-dimethacrylate, was synthesized and was used for the preparation of template-imprinted polymers. Interpenetrating networks consisting of two different crosslinking systems did not bring about any significant improvement in selectivity for racemic resolution. A strong temperature effect for racemic resolution was observed; an ethylene dimethacrylate-crosslinked, template-imprinted polymer showed an optimum selectivity at 75°C with a ratio of distribution coefficients of the D- and L-isomers of α = 4,56 for the separation of the racemate of the template.
Etching of 3C-SiC using CHF3/O2 and CHF3/O2/He plasmas at 1.75 Torr

This article discusses the etching and selectivity of 3C-SiC films grown on Si substrates using CHF3/O2 and CHF3/O2/He plasmas at a pressure of 1.75 Torr. The addition of helium increases the etch rates of SiC and Si for most CHF3 and O2 concentrations. For both CHF3/O2 and CHF3/O2/He plasmas with O2 concentrations up to 85%, the SiC etch rate increases monotonically and the Si etch rate decreases monotonically with increased percentages of O2. At an O2 concentration of 80%, the addition of helium to the CHF3/O2 plasma results in an etch rate of 1267 A/min, which is the highest reported for etching 3C-SiC using a CHF3-based plasma in a conventional, parallel plate plasma reactor. The addition of helium also increases the etch anisotropy. This study also investigated aluminum micromasking of SiC etch fields and finds the primary source to be sputtered aluminum from the etch mask.
Aerosol properties and their spatial and temporal variations over North China in spring 2001

Aerosol properties and their spatial and temporal variations over North China were analysed based on ground-based radiometer data for spring 2001. On the basis of the retrievals from sun/sky radiance and broad-band radiation measurements at four AERONET stations and eight first-class radiation stations over North China, the analysis comprised a detailed description of aerosol loading, size and absorption in this period. The impact of dust events on aerosol properties over the downwind region was emphasized.Heavy aerosol loading and notable temporal variation over North China were revealed by both datasets. The average aerosol optical depth at 750 nm at the eight radiation stations ranged from 0.32 in Ejinaqi to 0.68 in Beijing, with the averaged coefficient of variation being 70%. Aerosol optical depth was dominantly contributed to by dust over western China, with 68% (±5%) of aerosol optical depth at 550 nm being attributed to large dust aerosols. A dramatic increase in aerosol optical depth associated with the remarkable decrease in the Ångstrom wavelength exponent was observed in Beijing and Xianghe during the dust episode. This indicated that a huge number of large particles were emitted into the atmosphere during the dust period, with the result that the contribution to aerosol optical depth from coarse particles approached the value observed in the dust source region. Anthropogenic pollution also frequently contributed to the high aerosol optical depth in Beijing and Xianghe, but this was characterized by fine particles, with more than 70% of aerosol optical depth at 550 nm being attributed to fine particles. Pure desert aerosol in Chinese dust source regions absorbs much less solar radiation than predicted by known aerosol models. The retrieved single-scattering albedo was around 0.98 (±0.01) and had little wavelength dependence, which is in agreement with the ground-based and satellite retrievals in other dust source regions. Contrarily, anthropogenic aerosol exhibits much stronger absorption in the urban region, with the single-scattering albedo ranging from 0.89 ± 0.04 (at 440 nm) to 0.83 ± 0.05 (at 1020 nm). Due to the large difference in the absorption between dust and anthropogenic aerosol, the consequence of the input of a large volume of dust aerosols is not only to enhance the aerosol loading but also to reduce the aerosol absorption. Retrievals in Beijing showed that the single-scattering albedo increased to about 0.90 and had little spectral dependence when anthropogenic pollution and a dust event together affected Beijing; as for the pure dust period, it ranged from 0.92 at 440 nm to 0.97 at 1020 nm. The significant decrease in the aerosol absorption due to the dust outbreak can result in a decrease in aerosol atmospheric heating efficiency; this warrants further research since the increasing trend of aerosol loading with strong absorption in China is supposed to play an active role in regional and global climate change and the hydrological cycle.
Lixiviação do hexazinone e da mistura hexazinone + diuron em colunas de solos com texturas distintas.

Objetivou-se avaliar a lixiviacao do hexazinone isoladamente e da mistura com o diuron, em solos de texturas contrastantes, em colunas de solos sob diferentes precipitacoes. Utilizou-se um Latossolo Vermelho – LV, de textura argilosa e um Neossolo Quartzarenico – NQ, de textura arenosa. As unidades experimentais foram constituidas por colunas de PVC preenchidas com solos, nas doses de hexazinone (LV - 375 g ha-1 e NQ - 225 g ha-1) e hexazinone + diuron (LV - 396 + 1.404 g ha-1 e NQ - 264 + 936 g ha-1). Adotou-se o esquema fatorial 6 x 6 no delineamento em blocos casualizados, com tres repeticoes. No fator A foram avaliadas as precipitacoes de 0, 20, 40, 60, 80 e 100 mm, e o fator B as profundidades (0-5, 5-10, 10-15, 15-20, 20-25 e 25-30 cm) das colunas. Posteriormente a simulacao da chuva as colunas foram abertas longitudinalmente e ao longo dessas foram semeados Cucumis sativus. Independente da textura do solo, o hexazinone e a mistura hexazinone + diuron nao ultrapassaram a camada de 10-15 cm do solo, na lâmina de 0 mm. O hexazinone e a mistura hexazinone + diuron apresentaram fitotoxicidade da especie bioindicadora na camada de 20-25 cm em LV, e chegando ate 25-30 cm no NQ, na maior lâmina simulada. Concluiu-se que nao houve diferenca no potencial de lixiviacao do hexazinone quando em mistura com o diuron nos solos com texturas distintas, entretanto a composicao textural argilosa, teor de materia orgânica do solo e precipitacoes pluviometricas influenciou a lixiviacao.
Chemical modification of diamond surface using a diacyl peroxide as radical initiator and CN group-containing compounds for the introduction of the CN group

The introduction of the CN group onto a diamond surface was attempted using diacyl peroxides with CN group-containing compounds. When acetonitrile was used as solvent for the radical reaction process, the CN group was introduced onto the diamond surface, however when benzonitrile was used no CN group was introduced. The mechanism for introduction of the CN group onto the diamond surface is proposed to be as follows: Acetonitrile includes an alkyl group in its structure. The radical species derived from the diacyl peroxide appears to abstract the hydrogen atom from the alkyl group, with the radical species generated from acetonitrile then reacting with the diamond surface activated by the radical species derived from the diacyl peroxide. However, for benzonitrile, no hydrogen abstraction reaction can proceed as it has no alkyl group.
Determining the proper time for picking lulo fruit (Solanum quitoense Lam. var.quitoense and septentrionale)

Resumen: Este trabajo se oriento a evaluar las caracteristicas fisicoquimicas de los frutos de dos variedades botanicas de lulo (Solanum quitoense Lam. var. quitoense y septentrionale) cultivadas en Garzon, Huila. La evaluacion de los frutos se realizo mediante el promedio del peso fresco y seco, la perdida de peso, la firmeza de la fruta, la acidez titulable, los solidos solubles totales (SST), la relacion SST / acidez titulable y los dias de cosecha a maduracion. Los frutos se cosecharon en cuatro estados de maduracion y se expusieron a temperatura ambiente (30 ± 2° C y 50 ± 5% HR) y a temperatura de refrigeracion (13 ± 1° C y 85 ± 2% HR). Los frutos testigo se cosecharon con madurez de consumo. Los parametros de calidad evaluados se midieron cuando los frutos llegaron a la madurez de consumo, y estos parametros se compararon con los medidos en los frutos testigo. La epoca de cosecha a maduracion y el pH fueron afectados por el estado de maduracion. Los frutos cosechados en un estado temprano de maduracion demoraron mas tiempo en madurar. Los factores ‘estado de maduracion’ y ‘condiciones de almacenamiento’ influyeron sobre la firmeza de los frutos y sobre la relacion SST/acidez titulable. Los SST fueron afectados por el estado de madurez y las condiciones de almacenamiento. La acidez titulable de los frutos dependio de la variedad botanica. La perdida de peso durante el almacenamiento fue determinada por los tres factores evaluados. Los frutos cosechados entre 50 y 75% de maduracion mostraron los mejores valores en cuanto a los parametros de calidad, en relacion con frutos cosechados en estados de maduracion mas tempranos.
Atomic Fukui indices from the topological theory of atoms in molecules applied to Hartree-Fock and correlated electron densities

Rigorous definitions of the atomic Fukui indices, based on the topological theory of atoms in molecules, are proposed. Spin contributions to the electron density responses to electron detachment /attachment are quantified with the intra- and interspin indices. The atomic Fukui indices are calculated within five different levels of approximation for a series of six oxygen-containing molecules. Results of these test calculations suggest that in order to obtain reliable estimates of the indices at least the ROHF level of theory has to be employed
Removal and recovery of Ni(II) ions from synthetic wastewater using surface modified Strychnos potatorum seeds: experimental optimization and mechanism

Strychnos potatorum seeds have been utilized for the preparation of adsorbent, surface modified S. potatorum seeds (SMSP), by sulfuric acid treatment with 1:2 ratios of precursor to sulfuric acid. The adsorption process depends on the solution pH, adsorbent dose, contact time, initial Ni(II) ions concentration, and temperature. The adsorption kinetics of Ni(II) ions removal by the SMSP was relatively fast and it reaches the equilibrium at 30min. The maximum removal of Ni(II) ions was observed at an optimum conditions: pH of 5.0, adsorbent dose of 5g/L, contact time of 30min, and at temperature of 30˚C for an initial Ni(II) ions concentration of 100mg/L. In order to investigate the adsorption kinetics for the removal of Ni(II) ions by SMSP, pseudo-first-order and pseudo-secondorder kinetic models were studied. It was observed that the pseudo-second-order kinetic model fits the experimental data better than the pseudo-first-order kinetic model with good coefficient of determination values. Adsorption mechanism was discussed with different models such as intraparticle diffusion, Boyd kinetic, and shrinking core models. It was observed that the adsorption process was controlled by both film and particle diffusion. The effective diffusivity and diffusivity values were estimated from the Boyd kinetic and shrinking core models, respectively. Adsorption isotherm data were tested with the Langmuir, Freundlich, Temkin, and Dubinin‐Radushkevich models. It was observed that the Freundlich model fits the isotherm data better than other isotherm models with good coefficient of determination values. The Freundlich constant “n” was found to be of 3.888g/L which indicates that the adsorption of Ni(II) ions onto the SMSP followed the physical process. The thermodynamic parameters such as change in free energy, enthalpy, and entropy were also calculated. It was found that the adsorption process was spontaneous and exothermic in nature.
On the Interfacial Electronic Structure Origin of Efficiency Enhancement in Hematite Photoanodes

The electronic structure origins of interfacial losses in hematite photoanodes and the cause of the literature-reported order-of-magnitude photocurrent increase upon short high-temperature annealing are investigated. Synchrotron-based soft X-ray absorption spectroscopy is used to probe the unoccupied states at and near the interface between hematite (α-Fe2O3) and fluorine-doped tin oxide (FTO). Oxygen K-edge and iron L-edge absorption spectra indicate that the interfacial interaction reduces the degree of p–d hybridization and alters the crystal field in α-Fe2O3. The interface is found to be associated with a distribution of unoccupied oxygen p-hybridized states located below the lowest unoccupied iron 3d states in α-Fe2O3 (just below the conduction band minimum), which are eliminated with high-temperature processing. These data facilitate future efforts to engineer favorable interfacial compositions and associated electrochemical potential gradients within photoanodes, which are required to efficiently s.
Determinants of Paddy Straw Management Decision of Farmers in Punjab

This paper explored the present status as well as problems faced by the farmers with paddy straw management and sought to uncover the factors affecting farmers’ decision to burning of paddy straw. The study also highlighted the differences in the socio-eco-personal and psychological profile of the farmers using various alternative techniques of paddy straw management vis-a-vis burning the straw. The study was carried out in Sangrur district of Punjab and 30 farmers each from four villages were selected randomly. Farmers’ perceptions were also considered while analyzing the data. The results revealed that ignoring the bad impact on environment, farmers are burning paddy straw as it was economically advantageous to them. The farmers were engaged in mechanical farming for tillage operations and clearance of fields. Issues related to technical and mechanical aspects were found to be important. The results of the binary logistic regression showed that farmers’ operational land holding, extension contacts and innovativeness were the significant factors contributing to their decision to burn the paddy straw. Socio-ecopersonal and psychological variables (Z-test) such as annual income, extension contacts, risk orientation, innovativeness, mass media exposure and ecological consciousness were significantly different among the farmers managing paddy straw and those using alternative techniques other than burning. Thus, findings may provide useful information for effective management of paddy straw for economically viable and ecologically sustainable farming in this region.
Catalytic Asymmetric Oxidation of Heteroaromatic Sulfides with tert‐Butyl Hydroperoxide Catalyzed by a Titanium Complex with a New Chiral 1,2‐Diphenylethane‐1,2‐diol Ligand

Heteroaromatic sulfoxides, especially 1H-benzimidazolyl pyridinylmethyl sulfoxides, usually used as the blockbuster gastric proton pump inhibitors (PPIs), have been prepared highly enantioselectivily by catalytic asymmetric oxidation of sulfides attached to nitrogen-containing heterocyles with tert-butyl hydroperoxide in the presence of a chiral titanium complex, formed in situ from Ti(iPrO)(4), chiral 1,2-diphenylethane-1,2-diol 3c and water. The chiral sulfoxides were obtained in high yield (97%) with excellent enantiomeric excess (tip to 98%). ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)