Miracle-dz/UniFAR-FTUs huggingface dataset:
A model study of the κ-refinement procedure for fitting valence electron densities

Monopole electron-density deformations for first- and second-row atoms are obtained using Hirshfeld partitioning of near Hartree–Fock-limit electron densities for 28 diatomics. The κ-refinement model [Coppens, Guru Row, Leung, Stevens, Becker & Yang (1979). Acta Cryst. A35, 63–72] is applied to these monopole deformations and its success in modelling them is gauged by means of deformation radial distribution plots, r2Δρ(r), and κ and charge-transfer values. The κ-refinement procedure proves to be remarkably successful in modelling the monopole deformations in this work. This in large part explains the successful application of the κ-refinement model to X-ray diffraction data, where it is capable of yielding an excellent point-charge model of the electrostatic potential in molecules and crystals.
Evaluation of phosphorus mobilization potential in rewetted fens by an improved sequential chemical extraction procedure

After rewetting of peatlands, phosphorus (P) pore‐water concentrations were up to three orders of magnitude greater than under pristine conditions. It was hypothesized that different mobilization processes such as ion‐exchange reactions, biotic/abiotic redox reactions, acidification and ongoing anaerobic decomposition of particulate organic matter by hydrolytic cleavage and fermentation might be responsible. To identify P pools in peat samples of varying degrees of decomposition, we modified and improved a sequential chemical extraction method that allowed conclusions on potential mobilization mechanisms in rewetted peatlands. The results indicated that the earlier drainage of rewetted fens strongly increased the P mobilization potential in the upper decomposed peat layers. Accordingly, the amount of P bound to redox‐sensitive (bicarbonate/dithionite soluble) compounds (BD‐P) was, on average, one order of magnitude greater in decomposed peat of rewetted fens (5.4–14.3 μmol P g−1 dry matter or DM) than in underlying less‐decomposed peat layers (0.2–1.9 μmol P g−1 DM) or slightly decomposed peat derived from pristine fens (0.4–2.0 μmol P g−1 DM). The BD‐P fraction found in the upper very decomposed peat layers appears to be most important for P mobilization in rewetted fens and accounted for 85% of the variability of P mobilization rates. Despite uncertainties regarding P diagenetic processes in peat, as well as the development of microbial decomposition processes, in the long‐term, high pore‐water P concentrations can be expected in rewetted fens for decades to come.
Influence of bacterial exopolymers on cell adhesion of Desulfovibrio vulgaris on high alloyed steel: Corrosion inhibition by extracellular polymeric substances (EPS)

Extracellular polymeric substances (EPS) were studied with regard to their potential application as inhibitors of biocorrosion. EPS that have been isolated from biofilms of sulphate‐reducing bacteria (SRB) were adsorbed on samples of high alloyed steel (type 1.4301) at different temperatures. The samples were exposed to SRB containing solution and afterwards analysed by fluorescence microscopy (FM). The results show that the EPS form an incomplete layer and lead to a smaller amount of cell adhesion when compared to pure surfaces. The results are discussed with regard to the application of EPS for the prevention of biofilm formation.
Flow phenomena and local heat and mass transfer in corrugated passages

En se basant sur une methode de mesure des transferts locaux de masse et de chaleur developpee dans une etude anterieure, une procedure a ete formulee pour la determination des transferts locaux de masse et de transfert dans des structures ondulees. En utilisant l'analogie existant entre les transferts de masse et de chaleur, cette technique permet la determination des distributions de transfert de chaleur dans chaque structure a resolution locale elevee
Morphology of gel‐spun polyethylene fibers

Nitric acid etching studies have been conducted on samples of commercially available highly oriented gel-spun polyethylene fibers : Spectra TM 900 and 1000 from AlliedSignal Inc. The results show that the acid attacks the fiber, increases crystallinity as observed by X-ray diffraction, increases the enthalpy of melting of unconstrained fibers by 13-25%, and removes topological constrains thus facilitating the crystallization of chain segments in the noncrystalline regions. The acid functionalizes the fiber, creating various oxygen-and nitrogen-containing moieties, specifically (C=O)-, -C=C-, and -NO 2 groups. The small weight loss upon etching, less than 2%, and the fact that fibers weaken but do not fragment suggests that the gel-spun and -drawn morphology is more resistant to acid attack than are other morphologies of polyethylene. Photomicroscopy shows that acid etching opens cracks normal to the fiber axis. That the acid can attack the gel-spun fibers indicates the presence of structural imperfections such as folds, molecular kinks, or uncrystallized regions within the fibers. Infrared analysis on virgin fibers shows the absence of absorption bands normally associated with the presence of chains lying within amorphous regions in polyethylene. These and other morphological features are integrated into a description of the structure of commercial gel-spun polyethylene fibers. © 1995 John Wiley & Sons, Inc.
Influence of copper nanoparticles on copper requiring enzyme

This study describes the influence of copper nanoparticles (CNPs) on activity and kinetic properties of a Cu2+ requiring sorghum oxalate oxidase (OxO). CNPs were synthesised by citrate-induced reduction of CuCl2 and their size (range 13–58 nm) was determined by transmission electron microscopy. The CNPs were characterised by scanning electron microscopy and X-ray diffraction studies. These CNPs enhanced OxO activity by 30%. Thermal and storage stability were increased, while Km value for oxalate decreased in the presence of CNPs. CNPs protected OxO against chelation by diethyldithiocarbamate, a Cu2+ specific chelator. The analytic use of OxO in the presence of CNP for determination of oxalate in food stuff is demonstrated.
Charge transport, charge injection and breakdown in polymeric insulators

A molecular approach is taken to describe charge transport and charge injection in insulating polymers. Localized acceptor and donor states are shown to develop from the energy bands of a regular polymer chain when polymer morphology is taken into account. Charge transport then requires resonance tunnelling between reduced and oxidized states and an important factor is the reorganization energy accompanying localization. The same processes, which are of an electrochemical nature, are used to describe electron transfer across electrode-polymer interfaces. The approach satisfactorily predicts low- and high-field conductivities and is compatible with electrostatic contact-charging phenomena. It also illuminates the likely initiatory stages of electrical and water tree formations at breakdown fields. A satisfying result is that similar models may be used to describe both insulating and 'synthetic metal' polymers at opposite ends of the conductivity spectrum.
Dielectric Constants of Liquefied Noble Gases and Methane

Dielectric constants of argon, krypton, xenon, and methane have been measured in the liquid and in the solid near the melting point. Values of the derived Clausius—Mossotti function are in all cases less than for the gas, indicating a decreased effective polarizability attributed to overlap effects.
INCREASED ENDOSPERM MODIFICATION OF ABRADED BARLEY GRAIN AFTER GIBBERELLIC ACID TREATMENT

Physiological and structural observations on barley grains revealed that the pericarp is impermeable to exogenous gibberellic acid. The use of a mechanical hand-mill abraded the pericarp at the non-embryo (distal) end of the grain without damaging the embryo or the overlying husk. When grown in gibberellic acid, the α-amylase content of these abraded grains was significantly higher than that of the controls. Malts prepared from abraded grains were visually identical with control malts prepared with gibberellic acid, but they gave higher hot water extracts. Grain abrasion permitted exogenous gibberellic acid to reach a larger number of aleurone cells, thus increasing the extent of endosperm modification during growth.
Analysis of the failure mechanism for a stable organic photovoltaic during 10 000 h of testing

The degradation and failure mechanisms of a stable photovoltaic device comprising a bilayer heterojunction formed between poly(3‐carboxythiophene‐2,5‐diyl‐co‐thiophene‐2,5‐diyl) (P3CT) and Buckminsterfullerene (C60) sandwiched between indium tin oxide (ITO) and aluminium (Al) electrodes were elucidated by the time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS) analysis in conjunction with isotopic labelling using 18O2 after a total testing time of 13 000 h. This experiment allowed us to understand the chemistry that takes place in three dimensions during degradation and failure of the device under accelerated testing conditions. The cell was subjected to continuous illumination with an incident light intensity of 1000 W m−2 (AM1·5) at 72 ± 2°C under a vacuum of <10−6 mBar. During the illumination period, IV‐curves were recorded at regular intervals and the short circuit current of the device was monitored every 10 s for 10 760 h. The total illumination time was 12 200 h. During this period of time, the device performance degraded and the device was finally left in the dark at 25°C in an atmosphere where the oxygen had been replaced with the isotope 18O2. After 800 h in this atmosphere in the dark, the final IV‐curves in the dark and under illumination were recorded. The main purpose of this work was the analysis using TOF‐SIMS imaging and depth profiling of the degraded cell. The combined analyses correspond to the three‐dimensional chemical imaging of the device showing specifically where the oxygen had reacted during exposure. Several general findings were made that are applicable to similar devices. It was found that the oxygen diffuses into the device through the Al electrode in between the Al grains and through microscopic holes in the Al electrode. Once inside the device the oxygen diffuses in the lateral and vertical plane until the counter electrode is reached. C60 was found to be susceptible to the incorporation of 18O but P3CT was not under the conditions in question. The other prominent degradation pathway was found to be the diffusion of electrode materials into the device. Both electrode materials diffuse through the entire device to the counter electrode. Copyright © 2007 John Wiley & Sons, Ltd.
Thermodynamic Properties of Water + Tetrahydrofuran and Water + 1,4-Dioxane Mixtures at (303.15, 313.15, and 323.15) K†

Properties like density and viscosity at (303.15, 313.15, and 323.15) K and refractive index at 303.15 K have been measured for binary mixtures of water + tetrahydrofuran and water + 1,4-dioxane. The excess molar volume (VE) has been calculated from the density results. Viscosity and refractive index data have been used to compute respectively deviations in viscosity (Δη) and molar refraction (ΔR) of the mixtures. Excess molar volume and deviations in viscosity and molar refraction data have been fitted to the Redlich−Kister equation to calculate binary coefficients and standard deviations. Furthermore, literature published vapor−liquid equilibrium data of the mixtures have been used to construct x−y composition curves and compared with the pervaporation curves. Results of this study indicate the importance of the pervaporation technique for the separation of mixtures over that of simple distillation at the azeotropic composition. Permeate samples were analyzed by refractive index as well as gas chromatog.
Physical Characterizations of a Screen‐Printed Electrode for Use in an Amperometric Biosensor System

Screen-printed electrodes are widely used in modern biosensor applications. The conditions under which screen-printing takes place contribute to the electrical properties of the electrodes produced. This article describes a disposable carbon paste electrode that is used as the basis of an amperometric immunosensor incorporating the electroactive polymer polyaniline. The electrodes are manufactured using a semiautomated screen-printing system. The conditions used for the screen-printing of the carbon ink were investigated using physical methods such as scanning electron microscopy and cyclic voltammetry to establish how differences in the carbon surface translated into changes in the performance characteristics of the electrode. A process of electrochemical surface pretreatment was studied with a view to maximizing amperometric responses for subsequent enzyme and antibody-based biosensor applications. Comparisons between the screen-printed electrodes and glassy carbon electrodes are also made.
Carbothermal Solid State Reduction of Manganese Ores: 2. Non-isothermal and Isothermal Reduction in Different Gas Atmospheres

Non-isothermal and isothermal carbothermal reduction of Australian Groote Eylandt and South African Wessels manganese ores was studied in hydrogen, helium, argon and hydrogen-carbon monoxide atmospheres. Reduction experiments were conducted in a fixed bed reactor in a vertical tube furnace, with on-line monitoring of gas composition by CO-CO 2 infrared sensor. The extent of reduction was calculated using the off-gas composition and oxygen content in the reduced samples measured by LECO. The reduced samples were analyzed by XRD and EPMA. Reduction of manganese ores was strongly affected by temperature and ore chemistry. In all gas atmospheres, the reaction rate increased with increasing temperature. The reduction rate of manganese ore in hydrogen was higher than in helium, and in helium higher than in argon. Rate and extent of reduction of Wessels ore were higher in comparison with Groote Eylandt ores.
Some Excited States of the Hydrogen Molecule. II. 1Πg(1s2pπ), 3Πg(1s2pπ), 1Δg(1s3dδ), 3Δg(1s3dδ), 1Δu(1s3dδ), 3Δu(1s3dδ)

Complete theoretical potential curves for the bound 1Δg(1s3dδ) and 3Δg(1s3dδ) states of H2 and for the long‐range portions of the repulsive 1πg(1s2pπ), 3πg(1s2pπ), 1Δu(1s3dδ), and 3Δu(1s3dδ) states of H2 are reported. Comparison of these results plus results from Paper I of this series to the conventional perturbation theory computations for the long‐range interactions of those states shows that the conventional perturbation results may be misleading if ``valence'' and ``overlap'' forces are not considered. The computed total energies at Re for the 1Δg(1s3dδ) and 3Δg(1s3dδ) states are —0.6570143 (—0.65778), and —0.6571785 (—0.65872 a.u.), respectively. The values in parentheses are experimental values. Spectroscopic constants and expectation values for some one‐electron operators for the 1Δg(1s3dδ) and 3Δg(1s3dδ) states are also presented. Two‐center and one‐center wavefunctions yielding comparable energies for the 1Δg(1s3dδ) state are compared through expectation values for a series of one‐electron opera.
Holding current and switch-on mechanisms in 12 kV, 100 A 4H-SiC optically triggered thyristors

Temperature dependence of the holding current has been studied in high-voltage (12 kV class) 4H-SiC optically triggered thyristors in the temperature range from 300 to 425 K. The holding current Ih monotonically decreases with increasing temperature T due to two factors: enhanced thermal ionization of comparatively deep Al acceptors in the p+ emitter and increasing carrier lifetime in the blocking p base. The Ih(T) dependence reveals the existence of a ‘weak point’ within the optical window, which is characterized by a substantially smaller critical charge than that within the remaining part of the window. Analysis of the Ih(T) dependence confirms that high-voltage SiC thyristors are switched-on at room temperature only at a high injection level in the blocking base. At elevated temperatures, the same thyristor is switched on by the ‘classical’ mechanism typical of Si thyristors. Effective shunting of the p++–n emitter junction affects the properties of the thyristor. Possible effective-shunting mechanisms are discussed.
Management of stem rot of groundnut through seed dressing fungicides and bio agent in natural and artificial inoculated condition

Pot trials were carried out in net house of Department of Plant Pathology, College of Agriculture, Junagadh Agricultural University, Junagadh during Kharif 2017. Eight seed treatments viz., seed treatment (ST) with carbendazim 50% WP 2 g kg-1, ST with tebuconazole 2 DS 1.5 g kg-1, ST with mancozeb 75% WP, ST with carboxin 37.5% + thiram 37.5% DS, ST with carbendazim 12% WP + mancozeb 63% WP, seed treatment with T. harzianum, ST with T. harzianum+ soil application T. harzianum 2.5 kg enriched in 250 kg FYM ha-1 10 g kg-1 at 30 DAS, ST with P. fluorescens + soil application P. fluorescens 2.5 kg enriched in 250 kg FYM ha-1 at 30 DAS and a control were tested as a seed treatments against S. rolfsii in natural and artificial inoculated condition. Results revealed that seed treatment with Trichoderma harzianum 10 g kg-1 seed + soil application T. harzianum 2.5 kg enriched in 250 kg FYM ha-1 at 30 days after sowing were recorded minimum stem rot incidence in natural (26.67%) and artificial (40%) condition and minimum disease severity in natural (22.67%) and artificial (39.33%) condition.
Plant proanthocyanidins. Part II. Proanthocyanidin-A2 and its derivatives

The 2,7″-epoxy-4,8″-biflavan structure (1) has been deduced for the natural proanthocyanidin-A2 on the basis of spectroscopic (13C and 1H n.m.r.) and chemical evidence. Spectroscopic data are also outlined which lead, in association with biogenetic arguments, to a proposal (1a) for the absolute stereochemistry of the natural product. Hydrogenolysis of proanthocyanidin-A2 leads to fission of the C–O and C–C inter-flavan bonds and formation of the phenols (20) and (22). The same technique also leads to rupture of the inter-flavan linkage of dimers of the B group and hence to a novel micro-procedure for their identification. The isolation and characterisation of three trimeric proanthocyanidins based on A2 is also discussed.
Direct Determination of Aluminum in Archaeological Clays by Laser‐Induced Breakdown Spectroscopy

Abstract Instrumental techniques that allow the direct analysis of solids with little or no sample preparation are particularly important for the evaluation of samples that are difficult to analyze such as refractory or geological materials. Laser‐induced breakdown spectroscopy (LIBS) is a promising technique for the direct, rapid analysis of elements in solid materials with minimal sample preparation. The main advantages over wet techniques are virtual nondestructiveness and analysis speed. The goal of this work is the direct determination of aluminum of archaeological pieces using laser‐induced breakdown spectroscopy. The corresponding signals of metals were interpolated from calibration graphs of different salts of the metals. The matrix effects from the direct determination of these elements were thoroughly investigated. The potential of this technique for direct quantitative analysis of real archaeological materials (from Department of Ancient Science, University of Zaragoza) was evaluated, and the reproducibility of LIBS spectra from different archaeological samples was measured as a function of the number of laser shots. Finally, the results from LIBS are compared with those obtained by laser ablation inductively coupled plasma mass spectrometry.
Performance, Cost Benefit, Carcass Quality and Organ Characteristics of Pigs Fed High Graded Levels of Brewers` Dried Grain Diets in the Humid Tropics

Twenty-four (Landrace x Large white) weaner pigs with average live weight of 6.36 kg (6.25-6.50 kg) were used to evaluate the performance, cost benefit, carcass quality and organ characteristics of pigs fed high graded levels of brewers’ dried grain (BDG) diets in the humid tropics. The diets contained 0, 30, 35 and 40% BDG in Treatments 1, 2, 3 and 4, respectively. The experiment was in a completely randomized design (CRD) with each treatment replicated three times. Live weight, weight gain, feed and protein intake, feed conversion ratio (FCR) and protein efficiency ratio (PER) were measured. Other measurements were feed cost of weight gain, gross margin, warm dressed weight, carcass and organ characteristics. Results showed that weaner pigs fed 40% BDG diet had significantly (P<0.05) higher protein intake (113.65 g) than others, while increasing levels of BDG in the diets significantly (P<0.05) decreased feed cost at the weaner stage. At the grower stage, pigs fed 35% BDG diet had weight gain, FCR and PER values similar to those fed control diet, while BDG diets significantly affected back fat (1 rib) thickness, carcass length and percent st spleen. It was concluded that weaner pigs could be fed 40% BDG diet to reduce feed cost, without adverse effect on growth performance. At the grower stage, the optimum inclusion level of BDG in the pig’s diet should be 35%, although 40% BDG diet could be fed to reduce feed cost without adverse effect on carcass quality and organ characteristics of the pigs.
Cement-Admixture Interactions Related to Aluminate Control

Proper aluminate control has a strong effect on the performance of most portland cement based mixtures. Insufficient aluminate control typically results in poor admixture dosage efficiency, loss of workability, and in extreme cases abnormal retardation of strength development. The amount of soluble sulfate needed for proper aluminate control depends on the reactivity of the aluminate phases, not the nominal amount given by chemical analysis. Many admixtures impact both the reactivity of the cement phases, the dispersion and wetting of cement grains, and sometimes also the rate of dissolution of the sulfates. Hence, it is imperative that cement and admixture must be tested together in performance tests. This paper reviews some basic cement-admixture chemical interactions and presents some examples of the application of isothermal calorimetry as a performance test of the hydration kinetics of portland cement in the presence of admixtures.
Arsenic uptake by the Douglas‐fir (Pseudotsuga menziesie)

The Douglas fir (Pseudotsuga menziesie) growing in an arsenic-rich gold-bearing region contains elevated arsenic concentrations in new-growth stems (374 ppm dry weight (dw)) and needles (257 ppm dw). Speciation of methanol-water extracts by using high-performance liquid chromatography-inductively coupled plasma mass spectrometry show that arsenite is the major species in needles but arsenate is more dominant in stems. Only traces of methylarsenicals are present. Arsenic concentrations in other tree species growing in the region are genetally much lower; dimethylarsinate was extracted from a spruce cone.
A Review on Modeling of Pore-Blocking Behaviors of Membranes During Pressurized Membrane Filtration

Pore blocking is one of the critical factors governing the overall performance of membrane filtration systems. Pore blockage leads to a large resistance to filtration, giving rise to a sharp decline in the filtrate flux rate under constant pressure conditions and a severe increase in the pressure for operation under constant flux conditions during membrane filtration. In membrane filtration work, blocking filtration laws are widely used to interpret the membrane fouling in membrane filtration. This article presents a systematic review on the theoretical developments of mechanistic models related to the blocking filtration laws for describing the membrane fouling in membrane filtration. Equations for constant pressure and constant flux separations in the interstices of a membrane and on the surface are reported for the filtrate flow of Newtonian and power-law non-Newtonian fluids. The blocking filtration laws are useful also in the evaluation of the reduced pore size, maximum filtrate volume, and fouling potential. Moreover, the combined models are reviewed for a more complete, rigorous description of complicated behaviors of membrane fouling in which more than one mechanism operating successively or simultaneously is controlled.