Miracle-dz/UniFAR-FTUs huggingface dataset:
Optimization of Gaussian-type basis sets for local spin density functional calculations. Part I. Boron through neon, optimization technique and validation

Gaussian-type orbital and auxiliary basis sets have been optimized for local spin density functional calculations. This first paper deals with the atoms boron through neon. Subsequent papers will provide a list through xenon. The basis sets have been tested for their ability to give equilibrium geometries, bond dissociation energies, hydrogenation energies, and dipole moments. These results indicate that the present optimization technique yields reliable basis sets for molecular calculations. Keywords: Gaussian basis sets, density functional theory, boron–neon, geometries, energies of reactions.
Antioxidant activity of extracts and condensed tannins from leaves of Maytenus ilicifolia Mart. ex Reiss.

Maytenus ilicifolia (Celastraceae) is a native plant of South America and popularly known as "espinheira-santa". The aim of this study was to evaluate the antioxidant capacity of extracts and isolated compounds from this plant. The antioxidant activity of the crude and semipurified extracts and isolated compounds was evaluated through DPPH-radical and phosphomolybdenum-complex assays. By both methods, the ethyl-acetate fraction demonstrated better antioxidant capacity compared with vitamin C and trolox. In the compounds, the higher the number of hydroxyls, the greater the antioxidant activity. In addition, stereochemistry influenced antioxidant activity, i.e., compounds with 2R,3R showed greater activity than those with 2R,3S.
Review: Steam distilled spirits from fermented grape pomace Revision: Bebidas destiladas obtenidas de la fermentación del orujo de uva

Grape pomace is the solid residue left after juice extraction from grapes, and represents in Mediterra nean countries the most important by-product of the winemaking industry. Steam distillation of fer mented grape pomace will eventually produce a spirit, designated as bagaceira in Portugal, orujo in Spain and grappa in Italy. This paper comprehensively reviews fundamental and applied aspects of the manufacture of these spirits, encompassing their composition as well as metabolic reactions and microbial ecology that determine such composition during fermentation. These spirits adhere to maxi mum levels of methanol (potential toxic compound) and 2-butanol (potential flavor defect) fixed by EC regulations. Available studies pertaining to bagaceira, orujo and grappa have indicated that the final quality of these spirits depends strongly on the quality of the fresh grapes, the storage condi tions, and the distillation equipment and procedure employed.
Analysis of membrane pore-blocking models applied to the MF of real oily wastewaters treatment using mullite and mullite–alumina ceramic membranes

AbstractIn microfiltration (MF) membrane processes the typical variation of the flux with time is that of initial rapid decrease followed by a long and gradual decline. The results of an experimental study regarding analysis of membrane pore-blocking models in separation of oil from oily wastewaters outlet of desalting unit of Seraje, Ghom, Iran gas wells are presented. Mullite and Mullite–Alumina (25, 50 and 75% alumina content) membranes were synthesized from kaolin clay and α-alumina powder as MF ceramic membranes. Hermia’s model was used to investigate the fouling mechanisms of membranes at different time intervals (0–2.5, 0–5, 5–20, 20–120 min), and (0–120 min). It can be found that Hermia’s model cannot be applied for prediction of permeation flux in any limited intervals of time since by increasing of time the filtration pore-blocking behavior changes and one model cannot predict pore-blocking behavior in all filtration time. In addition for (0–5 min) interval, maximum error of predicted permeation.
Comparison of local‐density and Hartree–Fock calculations of molecular polarizabilities and hyperpolarizabilities

This paper presents a comparison between density functional theory local density approximation (LDA) and Hartree–Fock approximation (HFA) calculations of dipole moments, polarizabilities, and first hyperpolarizabilities, using ‘‘comparable’’ basis sets, in order to assess the relative quality of the LDA and the HFA for calculating these properties. Specifically, calculations were done using basis sets of roughly double or triple zeta plus polarization quality, with and without added field‐induced polarization (FIP) functions, for the seven small molecules H2, N2, CO, CH4, NH3, H2O, and HF, using the HFA option in the program HONDO8 and the LDA options in the programs DMol and deMon. For the calculations without FIP functions, the results from HONDO8 HFA and deMon LDA, both of which use Gaussian basis sets, are very similar, while DMol, which uses a LDA numerical atomic orbital basis set, gives substantially better results. Adding FIP functions does much to alleviate these observed basis set artifacts and .
Predicting In-Cylinder Soot in a Heavy-Duty Diesel Engine for Variations in SOI and TDC Temperature Using the Conditional Moment Closure Model

Numerical simulations of in-cylinder soot evolution in the optically accessible heavy-duty diesel engine of Sandia National Laboratories have been performed with the multidimensional conditional moment closure (CMC) model using a reduced n-heptane chemical mechanism coupled with a two-equation soot model. Simulation results are compared to the high-fidelity experimental data by means of pressure traces, apparent heat release rate (AHRR) and time-resolved in-cylinder soot mass derived from optical soot luminosity and multiple wavelength pyrometry in conjunction with high speed soot cloud imaging. In addition, spatial distributions of soot relevant quantities are given for several operating conditions.
Bone Engineering by Biomimetic Injectable Hydrogel

Osteoporosis is a multifactorial bone disease characterized by low bone mineral density (BMD) and deterioration of micro-architecture of cancellous bone leading to bone fragility and risk of fractures. In the current work, a novel tissue engineering strategy was experimented to enhance bone architecture in the risk areas via local injection of a biomimetic/osteoinductive injectable hyaluronan based hydrogel loaded with nano-hydroxyapatite crystals (Hya/HA) with/without bone morphogenetic protein (BMP-2), in distal femur of normal and ovariectomized New Zealand white rabbits. Our results revealed the osteoinductive effect of the Hya/HA composite that enhanced bone density and architecture of the rabbit distal femur.
High-throughput ab initio screening of binary solid solutions in olivine phosphates for Li-ion battery cathodes

A promising approach to improving the performance of iron-phosphate FePO4 cathode materials for Li-ion batteries is to partly or fully substitute Fe with other metals. Here, we use high-throughput density-functional theory (DFT) calculations to investigate binary mixtures of metal atoms M and M′ in (Li)MyM′1−yPO4 olivine phosphates. We determine the formation energy for various stoichiometries of different binary combinations of metals for the cases of full lithiation and delithiation. Systematic screening of all combinations of Fe and Mn with elements of the 3d transition-metal (TM) series allows us to identify trends with average band filling and atomic size. We also included compounds that verify the observed relations or that were discussed as cathode materials, particularly Ni–Co, V–Cu and V–Ni, as well as combinations with 4d TMs (Fe–Zr, Fe–Mo, Fe–Ag) and with Mg (Fe–Mg and Ni–Mg). Based on our DFT calculations for each compound, we estimate the volume change during intercalation, the intercalation voltage, the energy density and the thermal stability with respect to reaction with oxygen. Our calculations indicate that the energy density of the binary TM phosphates increases with average band filling while the thermal stability of the compounds decreases.
Asphaltenes and Other Natural Surfactants from Cerro Negro Crude Oil. Stepwise Adsorption at the Water/Toluene Interface: Film Formation and Hydrophobic Effects

The adsorption of asphaltenes and other natural surfactants at the water/toluene interface has been studied here, using both the ring and pendant drop method to measure the interfacial tension (γ). The dependence of γ on the logarithm of the sample concentration (ln C) (represented as the γ(ln C) isotherm) leads to a stepwise isotherm similar to that corresponding to the adsorption of asphaltenes at the toluene/silica interface. As is the case for the toluene/silica interface, the stepwise γ(ln C) isotherm seems to be the result of adsorption at the toluene/water interface of molecules, as well as aggregates formed in solution. Once adsorbed, these aggregates flocculate at the interface, leading to the well-known three-dimensional asphaltene films. In agreement with previous evidence from thermal lens experiments, the onset of asphaltene aggregation was observed near a sample concentration of C = 60 mg/L. Although the presence of aliphatic (acid fraction soluble in heptane, AFSH) and other types of acidic.
Characterization of cadmium doped zinc oxide (Cd : ZnO) thin films prepared by spray pyrolysis method

Thin films of cadmium doped zinc oxide (Cd : ZnO) with different cadmium concentrations have been prepared by the spray pyrolysis method on different substrates at 400 °C. The physical properties of the films were studied as a function of increasing cadmium dopant concentration (up to 25 wt%). The films were characterized by different methods to understand their structural, optical and electrical properties. Energy dispersive x-ray diffraction spectroscopy analysis showed that the Cd concentration in the solid film is slightly lower than that of the starting solution. The x-ray diffraction analysis revealed that the films are polycrystalline in nature having a hexagonal wurtzite type crystal structure with a preferred grain orientation in the (0 0 2) direction. Due to Cd doping, the degrees of polycrystallinity increased simultaneously and the orientation of the grains in the (0 0 2) axis is found to be deteriorated. Atomic force microscopy measurements reveal that the surface morphology of the films changes continuously with a decrease in the grain size due to Cd doping. Both photoluminescence and optical measurements showed that the band gap decreases from 3.12 to 2.96 eV with increasing Cd concentration. Increasing the Cd concentration also leads to the broadening of the emission peak and degrading the crystalline quality. The films are highly transparent in the visible region and the absorption edge showed a red shift. The sheet resistance of pure ZnO has been determined as 650 Ω sq−1 cm−1 and is decreased for higher concentrations of Cd doping. The characterization studies clearly indicate the incorporation of Cd into ZnO; hence the observed decrease in the optical band gap and electrical resistivity can be directly attributed to the effect of Cd ion incorporation into the ZnO lattice.
Experimental and Numerical Simulation of Radiolysis Gas Detonations and Mechanical Response of BWR Exhaust Pipes

Radiolysis gas (2H2 +O2 ) can accumulate in BWR steam piping in case of steam condensation. An ensuing detonation of the radiolysis gas is the likeliest cause of a pipe and/or valve damage. In the current work we investigate a typical BWR exhaust pipe, which connects the high pressure steam piping with the ambient atmosphere, under the following “worst case” scenario: (a) accumulation of radiolysis gas in an exhaust pipe, (b) fast valve opening to the high pressure system with steam at 70 bar, and (c) adiabatic pressurization of the radiolysis gas by the steam. Taking into account a water surface level of 6 m from the open end this leads to an equilibrium state of 20 bar pressure and 602 K temperature for the pressurized radiolysis gas. The main purpose of the current work was an experimental and numerical evaluation of the maximum pressure load and the integrity of the BWR exhaust pipe in case of a detonation of the pressurized radiolysis gas.Copyright © 2010 by ASME
REE diffusion in olivine

Abstract Diffusion of rare earth elements has been characterized in synthetic forsterite and natural olivine (Fo90) under dry conditions. Experiments were prepared by enclosing source material [mixtures of rare-earth element (La, Dy, or Yb) aluminate and synthetic forsterite powders in 3:1 proportions] and polished forsterite in platinum capsules. For buffered experiments on natural olivine, samples were placed with the source in AgPd capsules, sealed under vacuum in silica glass ampoules with a solid buffer (NNO, IW, or graphite ). In some experiments, ground natural olivine was also incorporated into the source material. Prepared capsules were annealed in 1 atm furnaces for one hour to several weeks at 850 to 1300 °C. REE distributions in olivine were profiled by Rutherford backscattering spectrometry (RBS). The following Arrhenius relation is obtained for Dy diffusion in forsterite: DDy = 8.0 × 10-10 exp(-289 ± 21 kJ mol-1/RT) m2/s. Diffusivities of Yb and La in forsterite and for Dy in natural olivine are similar. Experiments run on natural olivine show little dependence of diffusion on crystallographic orientation. The Arrhenius relation yields diffusivities about three orders of magnitude smaller than those determined for REE diffusion in olivine by Spandler et al. (2007) and suggests that timescales for preservation of REE signatures in olivine-hosted melt inclusions may be relatively long. REE diffusivities in olivine are an order of magnitude faster than those of REE+3 in enstatite (Cherniak and Liang 2007) and in diopside under most conditions (Van Orman et al. 2001). Hence, REE signatures in olivine are more likely to be altered by diffusion than those of clinopyroxene or orthopyroxene.
Methane production from municipal refuse: A review of enhancement techniques and microbial dynamics

Methane is recovered from about 100 municipal solid waste landfills in the U.S. in saleable volumes, although yields are 1 to 50% of the methane potential of refuse based on biodegradability data. Studies on the microbiology of refuse decomposition and efforts to enhance refuse methanogenesis are reviewed here. Results of studies on the effects of leachate recycle and neutralization, a reduction in refuse particle size, the addition of anaerobic sewage sludge or old refuse as a seed, nutrient addition, calcium carbonate addition, and moisture on methane production are examined in consideration of new findings on landfill microbiology. A four‐phase description of refuse decomposition with leachate recycle, including an aerobic phase, an anaerobic acid phase, an accelerated methane production phase, and a decelerated methane production phase, is proposed. Mass balances and pumping tests may be used to estimate the methane potential of a sanitary landfill. The use of empirical, zero, and first‐order models t.
Plasma Modification of Polymer Films Studied by Ellipsometry and Infrarot Spectroscopy

Thin polymer films (thickness d = 10 to 50 nm) modified in a low-pressure plasma of air, oxygen, argon, or tetrafluoromethane (p = 10 to 100 Pa) are investigated. It is shown that the interaction between plasma species (ions, electrons, radicals, UV quanta) and the polymer causes structural changes in the surface and subsurface regions. The formation of a modified surface layer can be observed. Fourier transform infrared (FTIR) attenuated total reflection (ATR) spectroscopy is used for the structural analysis of polymer modification. The structural changes detected by FTIR spectroscopy are accompanied by changes of optical properties, like the refractive index. The optical modification effects are investigated by spectroscopic ellipsometry (λ = 300 to 800 nm). For the analysis of the modification depth a multilayer model has to be applied to fit the ellipsometric data.
On the Limitations of UV−Fluorescence Spectroscopy in the Detection of High-Mass Hydrocarbon Molecules

This work compares UV-fluorescence (UV-F) and UV-absorption (UV-A) as detection methods in the analysis of coal and petroleum-derived materials, using size exclusion chromatography (SEC). A UV-F spectrometer that was equipped with a flow cell was connected in series to an SEC chromatograph with a conventional UV-A detector. Samples were examined via SEC, using both UV-F and UV-A detectors that were operating in tandem. They included asphaltenes from heavy petroleum residues and three fractions of a coal tar pitch obtained by solvent solubility separation. The chromatogram of the lightest fraction of the coal tar pitch (the acetone solubles) showed a single peak, with close agreement between both detection systems. The rest of the samples showed an early-eluting peak that corresponded to material excluded from the column porosity, in addition to a retained peak. UV-F showed little sensitivity to material eluting under the excluded peak in any of the samples and also was less effective than UV-A in detectin.
Characterisation of Tar produced in the Gasification of Biomass with in situ Catalytic Reforming

This paper concerns the cleaning of the hot gas produced by steam gasification of biomass in a fluidized bed. The cleaning takes place in a catalytic filter candle device placed directly in the freeboard of the bed. Such integration results in a compact processing unit and increased thermal efficiency; the result of the cleaning being carried out directly at the reactor outlet temperature. It thus lends itself to exploitation in distributed power generation systems utilizing renewable energy sources. Results are reported for runs performed in a bench scale fluidized bed steam gasifier fitted with a single full-size catalytic candle filter. Tar and particulates in the product gas were sampled in accord with technical specification CEN/TS 15439 with analysis by UV and fluorescence spectroscopy.
Thermodynamics of aqueous urea solutions

A compilation of heat capacity, heat of dilution, and activity data for aqueous urea solutions is made from published sources. The existing apparent volume data are supplemented by new measurements at 0°, 40°, and 50°. The thermodynamic data are interpreted in terms of association models, and it is found that the use of Flory-Huggins statistics for the entropy of mixing of the various associated species and the solvent gives a much better description than mole-fraction statistics. Heats of association and equilibrium constants are evaluated.
Ti-Decorated Doped Silicon Fullerene: A Possible Hydrogen-Storage Material

From first-principles density functional electronic structure calculations, we show that Si60H60 forms a highly symmetric (meta)stable fullerene structure on which Ti atoms can be capped exohedrally in cationic form, enabling storage of hydrogen in the molecular state. Whereas the H atoms on a Si60H60 cage saturate the Si dangling bonds, the Ti+ ion sitting on the energetically favorable hexagonal face of the Si60H60 fullerene allows a maximum of four H2 molecules to be attached, with a binding energy intermediate between those of physisorption and chemisorption. However, two Ti atoms added to Si fullerene tend to dimerize, thereby reducing the hydrogen-storage efficiency. This clustering tendency of the Ti atoms on the fullerene surface can be avoided by doping the fullerene with P atoms. Our first-principles results show that Ti-decorated P10Si50H50 clusters can serve as a potential hydrogen-storage material, with a storage capacity of up to 5.23 wt % corresponding to full Ti coverage.
Lanthanum–Strontium–Manganese Perovskites as Redox Materials for Solar Thermochemical Splitting of H2O and CO2

A thermodynamic and experimental investigation of a new class of solar thermochemical redox intermediates, namely, lanthanum–strontium–manganese perovskites, is presented. A defect model based on low-temperature oxygen non-stoichiometry data is formulated and extrapolated to higher temperatures more relevant to thermochemical redox cycles. Strontium contents of x = 0.3 (LSM30) and x = 0.4 (LSM40) in La1–xSrxMnO3−δ result in favorable reduction extents compared to ceria in the temperature range of 1523–1923 K. Oxidation with CO2 and H2O is not as thermodynamically favorable and largely dependent upon the oxidant concentration. The model is experimentally validated by O2 non-stoichiometry measurements at high temperatures (>1623 K) and CO2 reduction cycles with commercially available LSM35. Theoretical solar–fuel energy conversion efficiencies for LSM40 and ceria redox cycles are 16 and 22% at 1800 K and 13 and 7% at 1600 K, respectively.
The effect of phosphorus and mulching on the efficiency of phosphorus use and productivity of wheat grown on a mountain Alfisol in the Western Himalayas

Abstract. A field experiment was conducted over two years in one of the mountain Alfisols of the Western Himalayas to study the effects of phosphorus and mulching on phosphorus use efficiency (PUE) and productivity of wheat (cv. S‐308) at difference growth stages. The source of phosphorus was single superphosphate at 0, 26, 52 and 78 kg P/ha whereas the sources of mulching materials were pine needles (Pinus longifolia), lantana weed (Lantana camara) at 8 t/ha and transparent polyethylene sheet compared with no mulch.
Ab initio DFT study of structural and mechanical properties of methane and carbon dioxide hydrates

The structural and mechanical properties of methane and carbon dioxide hydrates were investigated using density functional theory simulations. Well-established equations of state of solids and exchange-correlation functionals were used for fitting the unit lattice total energy as a function of volume, and the full second-order elastic constants of these two gas hydrates were determined by energy–strain analyses. The polycrystalline elastic properties were also calculated from the unit lattice results. The final results for methane hydrate agree well with available experimental data and with other theoretical results. The two gas hydrates were found to be highly elastically isotropic, but they differed significantly in shear properties. The presented results for carbon dioxide hydrates are the first complete set reported so far. The results are a significant contribution to the ab initio material characterisation of gas hydrates required for ongoing fundamental studies and technological applications.
Crystallization behavior of polypropylene/polyamide 6/montmorillonite nanocomposites

Polymer blended materials such as polyamide 6 (PA6)/polypropylene (PP) blends have received considerable attention in recent years. To improve the compatibility of PA6 and PP, compatibilizers like maleic anhydride-g-polypropylene (MPP) are often added. In addition, organically modified montmorillonite (MMT) is also used to improve the properties of various materials. In this work, the crystallization behavior of PP/PA6/MMT nanocomposites with MPP compatibilizer was investigated systematically. The annealing process effectively improved the crystallization of α-PP. The crystallization temperature (Tc) of PA6 was increased by ca 2–3 °C on introducing MPP or MMT alone to the PP/PA6 system, whereas Tc of PP underwent no obvious change. However, when MPP and MMT were added simultaneously, Tc of PP and PA6 increased by 6.6 and 4.2 °C, respectively, and a new crystallization peak corresponding to PP-g-PA6 copolymer phase was observed at 162.5 °C. The combined effect of MPP and MMT led to better compatibility of PP with PA6. Moreover, the results of a non-isothermal crystallization kinetics experiment revealed that the simultaneous introduction of MPP and MMT markedly shortened the crystallization time. Copyright © 2010 Society of Chemical Industry