Miracle-dz/UniFAR-FTUs huggingface dataset:
A new equation for calculation of chemical hardness of groups and molecules

Chemical hardness is considered to be a useful theoretical descriptor in many experimental and theoretical studies and this concept has several important applications in chemistry. In this study, an equation for atomic hardness is proposed. Following the equation for atomic hardness which is based on charges, ionisation energies and electron affinities of atoms, a new equation is obtained for the calculation of the chemical hardness of groups and molecules using the atomic hardness equation and the principle of chemical hardness equalisation. Molecular chemical hardness may be calculated using α and β parameters of atoms in a molecule or group through the use of the obtained molecular hardness equation. Furthermore, the advantage of this equation over other equations in the literature is that using this equation the chemical hardness of the charged groups and molecules can also be calculated. Besides, the relationship between molecular hardness and charge of molecule is examined using the results obtained from the new molecular hardness equation, and the partial charges of atoms in molecules are calculated with the help of derived equations.
Crystal structure of 3-{[4-(4-fluorophenyl)piperazin-1-yl]methyl}-5-(thiophen- 2-yl)-2,3-dihydro-1,3,4-oxadiazole-2-thione, C17H17FN4OS2

Abstract C17H17FN4OS2, triclinic, P1̅ (no. 2), a = 6.3278(8) Å, b = 9.6250(13) Å, c = 14.789(2) Å, α = 81.739(5)°, β = 82.226(4)°, γ = 76.611(4)°, V = 862.3 Å3, Z = 2, Rgt(F) = 0.0798, wRref(F2) = 0.2072, T = 150 K.
Current density mapping approach for design of clinical magnetic resonance imaging magnets

Novel current density mapping (CDM) schemes are developed for the design of new actively shielded, clinical magnetic resonance imaging (MRI) magnets. This is an extended inverse method in which the entire potential solution space for the superconductors has been considered, rather than single current density layers. The solution provides an insight into the required superconducting coil pattern for a desired magnet configuration. This information is then used as an initial set of parameters for the magnet structure, and a previously developed hybrid numerical optimization technique is used to obtain the final geometry of the magnet. The CDM scheme is applied to the design of compact symmetric, asymmetric, and open architecture 1.0-1.5 T MRI magnet systems of novel geometry and utility. A new symmetric 1.0-T system that is just I m in length with a full 50-cm diameter of the active, or sensitive, volume (DSV) is detailed, as well as an asymmetric system in which a 50-cm DSV begins just 14 cm from the end of the coil structure. Finally a 1.0-T open magnet system with a full 50-cm DSV is presented. These new designs provide clinically useful homogeneous regions and have appropriately restricted stray fields but, in some of the designs, the DSV is much closer to the end of the magnet system than in conventional designs. These new designs have the potential to reduce patient claustrophobia and improve physician access to patients undergoing scans. (C) 2002 Wiley Periodicals, Inc.
Adaptive speech analytics: system, infrastructure, and behavior

This paper describes an adaptive system and infrastructure for Speech Analytics, based on the UIMA framework and consisting of a set of analysis engines (analytics) and control units, whose input is an unspeciﬁed and ever changing number of continuous streams of audio data and whose output is the detection of events consistent with a focus of analysis and/or the discovery of relationships among the outputs of the constituent analytics in the system. The central theme presented concerns the ability of the system to use the meta-data generated during the analysis to adapt both the behavior of the underlying analytics engines and the overall data ﬂow to adjust the granularity and accuracy of the analysis in order to allow processing of increasing amounts of data with limited resources.
Hydrophilic Transformations in Polyhydroxyalkanoates

Some hydrophilic transformations in polyhydroxyalkanoates were assessed in this study. It was proved that polyhydroxybutyrate-graft-polyvinylacetate copolymers are more hydrophilic than polyhydroxybutyrate and exhibit a strong dependence between hydrophilicity and polyvinylacetate content in the copolymers. Water wettability of some polyhydroxyalkanoates was improved by H+ (300 keV, flux ranging from 1011 to 5 × 1013 ions/cm2), Ag+ (20 keV, fluences ranging from 1014 to 1016 ions/ cm2), and Na+ (25 and 12.5 keV to 5 × 1015 ions/cm2) implantation experiments. Additionally, surface properties were characterized by means of water drop contact angle, atomic force microscopy, X-ray diffraction, and infrared spectroscopy. The influence of surface morphology on the wettability was discussed.
A Thermal Method of Measuring the Vapour Pressure of an Aqueous Solution

The method described below of measuring the difference of vapour pressure between any two aqueous solutions, or between a solution and the solvent, arose from experiments on isolated surviving muscles, in which it was noticed that stimulation in nitrogen led to a large increase in the rate of resting heat-production. This increment in heat rate was traced finally to condensation of moisture on the muscle, due to the lowering of vapour pressure caused in the muscle by the accumulation of the products of activity. These experiments are described elsewhere. The unexpected sensitivity of the apparatus to a change of vapour pressure led to its trial with solutions of various concentrations held by strips of filter paper; the results were so promising that a special instrument was designed and constructed, which alone is referred to in the following pages. The method has various advantages: ( a ) it is direct and fairly exact, e. g . , the difference of vapour pressure between water and a not too dilute aqueous solution can be measured at any required temperature, within 1 to 2 per cent. ; ( b ) it is fairly rapid: a reading is obtained in 30 to 45 minutes and four or five measurements can be made at the same time, if desired, by a single observer; ( c ) it has a wide range, e. g . , one can measure, on the one hand, the difference of vapour pressure between 0⋅1 M. NaCl and 0⋅2 M. cane sugar, or, on the other, between 5 M. NaCl (5 g. molecules NaCl to 1000 g. H2O) and water, the latter difference being of the order of 500 times the former; ( d ) very small quantities of the solutions are required, enough namely to moisten 1 to 2 sq. cm. of filter paper, say 0⋅2 cc.
Similarities in STXM-NEXAFS Spectra of Atmospheric Particles and Secondary Organic Aerosol Generated from Glyoxal, α-Pinene, Isoprene, 1,2,4-Trimethylbenzene, and d-Limonene

The organic functional group composition of particles produced in laboratory “smog” chambers were characterized by scanning transmission X-ray microscopy (STXM) with near-edge X-ray absorption fine structure (NEXAFS) spectroscopy and characteristic spectral signatures for secondary organic aerosol (SOA) were identified. The main objective of this study is to compare the single particle functional group composition of SOA formed from five precursors (glyoxal, α-pinene, isoprene, 1,2,4-trimethylbenzene, and d-limonene) to the composition of ambient particles from multiple field campaigns. This has implications for understanding the potential contributions of particles similar to those produced in SOA chambers to ambient compositions during those campaigns. Glyoxal uptake studies showed absorption from mainly alkyl, carbon-nitrogen (C-N), and carboxylic carbonyl groups. The SOA formed from the photooxidation of α-pinene (with and without isoprene) showed stronger absorptions for alkyl and carbonyl groups than the SOA formed from glyoxal. The mass ratio of carbonyl to acid group was larger in α-pinene-only experiments relative to the mixed α-pinene-isoprene experiments. Of 338 single-particle spectra available from aerosol sampling at six field campaigns, 114 particles had spectral features that were considered similar to the chamber-SOA particles: MILAGRO-2006 (9 particles), VOCALS-2008 (41 particles), Whistler-2008 (22 particles), Scripps Pier-2009 (8 particles), Bakersfield-2010 (24 particles), and Whistler-2010 (10 particles). These similarities with chamber-generated SOA provide spectroscopic evidence of chemically similar SOA products from these precursors in ambient particles. Copyright 2013 American Association for Aerosol Research
Oxidative catalytic versatility of a trivacant polyoxotungstate incorporated into MIL-101(Cr)

The first immobilization of the trivacant Keggin-type polyoxometalate ([A-PW9O34]9−, PW9) to prepare a novel heterogeneous oxidative catalyst is here reported. PW9 was incorporated into the cavities of the chromium terephthalate metal–organic framework MIL-101(Cr). Characterization of the composite PW9@MIL-101 by powder X-ray diffraction, SEM-EDX, FT-IR, FT-Raman spectroscopy, N2 adsorption–desorption isotherms and 31P solid-state NMR confirmed that the structures of MIL-101 and the polyoxometalate anion were retained after immobilization. The composite PW9@MIL-101 revealed versatility as a heterogeneous catalyst to oxidize efficiently monoterpenes as well as to reach a complete desulfurization of a model oil containing the most refractory sulfur compounds in fuel, using in both systems acetonitrile as the solvent and H2O2 as the oxidant. Complete conversion of geraniol to 2,3-epoxygeraniol was achieved after the first 30 min at room temperature, while the total desulfurization of the model oil containing 1707 ppm of sulfur was attained after 2 h. In both systems the catalyst was recyclable for various cycles without a significant loss of activity. The stability and heterogeneity of the catalyst were confirmed by several techniques and by leaching tests.
Quasi-elastic neutron-scattering studies of intercalated molecules in charge-deficient layer silicates. Part 2.—High-resolution measurements of the diffusion of water in montmorillonite and vermiculite

The relative influence of water–surface and water–cation interactions in hydrates of the charge-deficient expanding-lattice layer silicates montmorillonite and vermiculite have been studied using high-resolution quasi-elastic neutron-scattering (QENS) measurements made with the back-scattering spectrometer at ILL, Grenoble. Detailed measurements have been made Ca2+–montmorillonite equilibrated at seven different water-vapour partial-pressure (p/p0) values and for Ca2+, Mg2+ and Na+ vermiculite samples at fixed p/p0.The QENS data are fitted to a model consisting of an elastic and a single Lorentzian quasi-elastic component plus a flat background. The quasi-elastic linewidth and the relative intensities of the three components are adjustable parameters. The resultant quasi-elastic broadenings were approximately five times smaller than the values derived previously from measurements at lower energy resolution. Also, the quasi-elastic scattering intensity increased with p/p0 and decreased with increasing scattering angle, the latter being the reverse of the behaviour observed at the broader energy resolution.The low- and high-resolution measurements taken together indicate the occurrence of two different phases of translational motion of water molecules not directly coordinated to the exchangeable (Ca2+) cations. These are attributed (i) to rapid localized motions in ‘cages’ bounded by the silicate sheets and the hydrated cations and (ii) to slower, longer-range inter-cage diffusion. In addition, the relative intensities of the quasi-elastic scattering at high and low wavevector transfer suggest that the high-resolution measurements also observe rotations of the complete six-fold coordinated hydration shells of the cations about one of the C3 axes of the octahedron. To explain the observed width, this rotation must have a correlation time of ca. 10–10 at ambient temperature.The present QENS data yielded effective diffusion coefficients for water in Ca2+–montmorillonite which increased rapidly from < 1.0 × 10–10 m2 s–1 at p/p0= 0.15 to ca. 4.5 × 10–10 m2 s–1 at p/p0= 0.33. At higher values of p/p0 the effective diffusion coefficients remained approximately constant within the limits of experimental error. For water adsorbed by vermiculite having Na+, Ca2+ or Mg2+ as the exchangeable cation the diffusion coefficient measured at p/p0= 0.76 was found to be significantly smaller than the corresponding value for Ca2+–montmorillonite. This may be attributed to the hindering effect of the more densely packed network of hydrated cations in the more highly charged vermiculite.
The crystal structures of nine K feldspars from the Adamello Massif (Northern Italy)

Table 1 of the paper by Dal Negro, De Pieri, Quareni & Taylor [Acta Cryst. (1978). B34, 2699-27071 contains incorrect values for some of the direct-cell angles and volumes. A corrected version of part of Table 1 is given.
Formation Mechanism of the Slice and Rod-Like Cerium Dioxide Precursor Particles

Ultra-fine cerium dioxide precursor particles was prepared with cerium (III) nitrate hexahydrate (Ce (NO3)36H2O) and urea (CO(NH2)2) at 85°C by homogenous precipitation method. Effects of reaction and ageing time on the morphology of the precursor particles were studied, the morphology of precursor particles was characterized by scan electronic microscope and the crystallinity of the precursors was studied by X-ray diffraction. The result showed that the mono-dispersed spherical particles turned into flower and bundle-like particles as reaction time increasing, the particles turned into slice and rod-like particles as the ageing time increasing, the transition process occurred in ageing process was later than that in the reaction process, the spherical particles were less crystallization and the slice and the rod-like particles were at a state of fine crystallization.
High‐Resolution X‐ray Diffraction and Fluorescence Microscopy Characterization of Alkali‐Activated Slag‐Metakaolin Binders

The effect of the activator concentration on the structure of alkali silicate-activated slag/metakaolin pastes is assessed through synchrotron radiation-based X-ray techniques. As main reaction products, both calcium aluminosilicate hydrate (C–A–S–H) and sodium/calcium aluminosilicate hydrate [(C,N)–A–S–H] type gels are formed in activated binders solely based on slag, along with the zeolitic products gismondine and garronite. In activated blended pastes, the inclusion of metakaolin in the binder hinders the formation of zeolite products, instead favoring the formation of a (C,N)–A–S–H type gel consistent with the activation of metakaolin in the presence of high concentrations of Ca. The formation of the two distinct binding products is confirmed by high-resolution X-ray fluorescence microscopy, where the “inner” products and the “outer” products have compositions consistent with (C,N)–A–S–H and C–A–S–H type gels, respectively. These results provide important new insights into the gel chemistry and micro/nanostructure of blended alkali-activated binder systems.
Influence of Catalyst Weight/Biomass Flow Rate Ratio on Gas Production in the Catalytic Pyrolysis of Pine Sawdust at Low Temperatures

Pine sawdust catalytic pyrolysis has been studied in a fluidized bed at temperatures of 650 and 700 °C. The experimental work was carried out in a bench-scale plant based on Waterloo Fast Pyrolysis Process (WFPP) technology. The Ni−Al catalyst used was prepared by coprecipitation with a molar ratio 1:2 (Ni−Al) and calcined at 750 °C for 3 h. The catalyst was not reduced prior to the biomass reaction. The influence of the catalyst weight/biomass flow rate ratio (W/mb) on the product distribution and on the quality of the gas product obtained was analyzed. An increase of the W/mb ratio increases the total gas yield and diminishes the liquid yield. When the W/mb ratio increases, H2 and CO yields increase while CO2, CH4, and C2 yields decrease. For W/mb ratios ≥ 0.4 h, no significant modifications are observed on the initial yields of different gases, and it is confirmed that under these conditions the initial gas composition is similar to that for thermodynamic equilibrium. For W/mb ratios < 0.4 h, a simple .
Direct Electrochemical Reduction of Titanium Dioxide in Molten Salts

Electrochemical methods and electrowinning of titanium have been promoted, unsuccessfully, for many years as a replacement for the current Kroll process, which has not achieved the same economies of scale as other light metals (eg. Al, Mg) have. One such method is the direct electrochemical reduction of titanium dioxide, which encompasses a range of processes involving the electrolysis of a molten salt and the subsequent reduction of titanium via the metal of the salt cation. Norsk Titanium AS, in a collaboration with Norsk Hydro, SINTEF, and NTNU through a Norwegian Research Council grant, has been actively involved in the development of such a process and the focus of this presentation is to give a summary of the research activities. Particular emphasis will be given to the fundamental reactions underlying the process.
Synthesis and characterisation of telechelic regioregular head-to-tail poly(3-alkylthiophenes)

An investigation into the Stille cross-coupling reaction as an alternative synthetic route to regioregular head-to-tail poly(3-alkylthiophenes) is presented. 2-Iodo-3-alkyl-5-tri-n-butylstannylthiophene derivatives were made, isolated and characterised and subsequently used in Pd0 catalysed cross-coupling reactions in different solvents. Short and long chain regioregular poly(3-hexylthiophenes) with over 96% head-to-tail coupling ratios between adjacent thiophene rings were obtained. The materials were analysed by gel permeation chromatography and NMR spectroscopy. Polymers with varying degrees of polymerisation were obtained depending on the conditions used. End group analysis has shown that polymers, functionalised with both iodo and tri-n-butyltin end groups can be obtained under certain reaction conditions. Preliminary homocoupling reactions were also conducted.
Efficient biodegradation of common ionic liquids by Sphingomonas paucimobilis bacterium

The biodegradation of ionic liquids (ILs) was evaluated by an indirect impedance technique, through which carbon dioxide production was measured during bioassay time. The biodegradation study was focused on finding a microorganism able to efficiently degrade common IL compounds. For the first time, a bacteria strain of Sphingomonas paucimobilis was employed in biodegradability tests of ILs, carried out for 37 commercial imidazolium-, pyridinium-, pyrrolidinium-, ammonium- and phosphonium-based ILs, including in the sample 12 different anions and 14 different cations. Remarkably, more than half of ILs studied (54% of the sample) exhibited a biodegradation percentage ≥60% after a 28-day incubation period with S. paucimobilis at 45 °C; therefore, they behave as easily biodegradable compounds from the indirect impedance test. In summary, current results suggested the possibility of biotreatment for the rapid and ultimate mineralisation of widely used ILs, such as BmimNTf2, BmimPF6, etc., which were noted as recalcitrant to biodegradation in previous standard tests with other microorganisms.
Photochemistry of atmospherically important free radicals: HO2

OH photofragments generated from the 220 nm photolysis of HO2 are interrogated using laser induced fluorescence. Internal energy distribution measurement combined with Doppler line shape analysis confirm that the excited electronic state of HO2 accessed at 220 nm is of A' symmetry and that 85 plus or minus 10% of the oxygen atoms resulting from the photodissociation are formed in their 1D excited electronic state. Very little of the 23,200 cm-1 available energy (less than 2%) appears as internal excitation of the OH fragment.
Dodecahedral Clusters and Novel Cubic Allotropic Forms of Carbon, Silicon, and Germanium: Computer Simulation

Abstract A method is described for building up novel three‐dimensional periodical structures consisting of atoms C, Si or Ge. Polyhedral dodecahedral shape clusters X20 are basis of such lattices. Three‐dimensional nets with simple cubic lattices can be produced on the base of X20 clusters. Each cluster X20 has six neighboring clusters X20. Two neighboring clusters are bound by two covalent bonds. It is found that large size cavities are contained in such structures. Cubic clusters X8 can be disposed in these cavities. Each cluster X8 has eight neighboring clusters X20 and is covalently linked with one of these clusters. As a result, periodical crystalline structures [X8@(X20)8]n (or [X28]n) with simple cubic lattice can be produced. The lattice parameters of these crystals were found using DFT‐PBE optimized calculations of clusters X8 @ (X20)8 and X8 @ (X20H13)8. Structure of the [C28]n crystal was obtained more accurate by the PBE96/FLAPW method. Calculations of density of states show that the crystal is dielectric with an energy gap of 3.3 eV.
Predictive simulations of the structural and adsorptive properties for PIM-1 variations

Despite the sizeable and growing body of research on polymers of intrinsic microporosity (PIMs), a greater understanding of the relationship between the monomer, polymer–polymer and polymer–gas interaction is of significant interest. Methane (CH4), carbon dioxide (CO2), oxygen (O2) and nitrogen (N2) adsorption isotherms at 20°C and up to 20 bar obtained from grand canonical Monte Carlo simulations are presented for PIM-1, PIM-1c, PIM-1n and PIM-1f. The new proposed structure, PIM-1f, is presented and characterised by geometric accessible surface area, pore size distribution, radial distribution function, X-ray scattering and gas adsorption isotherms. PIM-1f increased the geometric surface area when compared with PIM-1; however, the higher system density in combination with the lack of strong adsorption sites yielded the least effective adsorbent for the gases analysed in this study. The gas solubility and ideal solubility selectivity values are also presented and compared with available experimental data for all gases and several gas mixtures illustrating that PIM-1c is the most effective functionality studied for adsorbing these four gases. The conclusions made here are projected to facilitate the design of a material that combines the higher surface area of PIM-1f with the high adsorption capacity of PIM-1c, which will improve the performance of future PIMs.
Evaluating restoration success of rewetted peatlands: Recovery potential, temporal dynamics and comparison of monitoring approaches

Montane peatlands are prominent in terms of biodiversity and ecosystem functions, but threatened by unsustainable land use. Therefore, they are increasingly restored. However, the temporal dynamics of recovering peatlands are largely unknown, and current techniques for evaluating restoration success are insufficient. The thesis is a major advance in understanding the patterns and processes of peatland recovery, and contributes significantly to new monitoring methods.
Carbon nanofibers from carbon nanotubes by 1.2 keV Ar + sputtering at room temperature

Multi-walled carbon nanotubes (MWCNTs) were irradiated by 1.2 keV Ar ion beams for 15-60min at room temperature with current density of 60 µA/cm2. The morphology and microstructure are investigated by scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. The results show that carbon nanofibers are achieved after 60 min ion irradiation and the formation of carbon nanofibers proceeds through four periods, carbon nanotubes--amorphous carbon nanowires-- carbon nanoparticles along the tube axis--conical protrusions on the nanoparticles surface--carbon nanofibers from the conical protrusions.