Miracle-dz/UniFAR-FTUs huggingface dataset:
Mechanical and electronic properties of endofullerene Ne@C60 studied via structure distortions

Elastic, strength, electronic properties and vibrational spectra of Ne@C60 (I h) in its ground electronic state (X 1Ag) were investigated with density functional theory at B3PW91/6-31G level via structure distortions. The elastic properties were obtained from the potential energy curves (PECs) in all of the five independent distortional directions of the molecule with symmetries of 1. D 5d, 2. D 3d, 3. D 2h, 4. C 2h(1) and 5. C 2h(2). PECs were examined where the structure of Ne@C60 was destroyed. The necessary energies to destroy the structure were thus obtained, which illuminated the stability of Ne@C60. PECs were found to be anisotropic and were accurately fitted to polynomials. Elongations in the direction of D 5d and compression in D 2h encountered potential energy surface cross-linkages, which might be considered as a single electron pump for further application in the design of single electron devices. Time-dependent B3PW91/6-31G analysis predicted significant electronic spectra changes associated with structure distortions. Similarities and differences of the properties were compared with those in C60 and He@C60.
Numerical methods for Langevin type equations based on symplectic integrators

Langevin type equations are an important and fairly large class of systems close to Hamiltonian ones. The constructed mean-square and weak quasi-symplectic methods for such systems degenerate to symplectic methods when a system degenerates to a stochastic Hamiltonian one. In addition, quasi-symplectic methods' law of phase volume contractivity is close to the exact law. The methods derived are based on symplectic schemes for stochastic Hamiltonian systems. Mean-square symplectic methods were obtained in [17, 18] while symplectic methods in the weak sense are constructed in this paper. Special attention is paid to Hamiltonian systems with separable Hamiltonians, with additive noise, and with colored noise. Some numerical tests of both symplectic and quasi-symplectic methods are presented. They demonstrate superiority of the proposed methods in comparison with standard ones.
Ice 1h/water interface of the SPC/E model: Molecular dynamics simulations of the equilibrium basal and prism interfaces

The basal and prism interfaces formed by ice 1h and water in equilibrium are studied using the rigid SPC/E model of water, in the temperature range of 220–240 K close to one atmosphere. Density, translational, orientational, and dynamic order parameters exhibit smooth, continuous changes from crystal to liquid across the interface. For both planes, the most stable interface is observed at 225±5 K. For higher temperatures the interfaces melt, while for lower temperatures strong changes in the normal and transverse components of the pressure tensor flag the beginning of growth into the supercooled water. We define new charge density profiles and their window averages. These are analyzed to understand both the local charge inhomogeneity at the intrinsic interface and the interaction of solutes with the broad interface.
Flammability, Oil Resistance, and Interaction of Petroleum Fuels with Dichlorocarbene Modified Styrene Butadiene Rubber/Fly Ash Composites

The interaction of fly ash (FA) on dichlorocarbene modified styrene butadiene rubber (DCSBR) is evaluated with reference to their flame and oil resistance. Flame and oil resistance of the composite increased progressively with increasing filler content in DCSBR. The barrier properties of these composites are examined in an atmosphere of petrol, diesel and kerosene. The solvent uptake nature of composite is found to be much reduced. The solvent uptake is minimum for composites with 30 phr filler and increased with increasing filler content, which is presumably due to aggregation of filler at higher loading; activation parameters are also estimated.
Investigation of Interaction between a Dislocation and a Br— Ion in NaCl:Br— Single Crystals

Strain rate cycling tests were carried out under simultaneous Blaha effect measurement on NaCl single crystals doped with Br - . Curves of strain rate sensitivity (SRS) of flow stress versus stress decrement due to superimposition of oscillatory stress were obtained. The curves are stair-like and show two plateau regions at low and higher stress decrement, and a middle region where the SRS decreases with increasing stress decrement, as reported in a previous paper concerning KCl:Br - . The stress τ p at the first bending point of the curve, which is considered to be the effective stress due to Br-, decreases with increasing temperature and becomes zero at a critical temperature T c = 270 K. The difference SRSp between the SRS at the first and second plateau regions decreases with temperature in contrast to the case of KCl:Br - . This means that the force-distance profile of the interaction between a dislocation and a Br- ion for NaCl:Br - is different from that for KCl: Br- and is pointed near the top. It is found that the interaction energy between a dislocation and a Br- impurity for NaCl: Br- crystal is 0.37 eV.
Flame Synthesis of Nanoparticles

An overview of recent advances in the synthesis of nanoparticles by flame aerosol processes is given. In flame processes with gaseous precursors emphasis is placed on reactant mixing and composition, additives, and external electric fields for control of product characteristics. Thermophoretic sampling can monitor the formation and growth of nanoparticles, while the corresponding temperature history can be obtained by non-intrusive Fourier transform infrared spectroscopy. Furthermore, synthesis of composite nanoparticles for various applications is addressed such as in reinforcement or catalysis as well as for scale-up from 1 to 700 g/h of silica-carbon nanostructured particles. In flame processes with liquid precursors using the so-called flame spray pyrolysis (FSP), emphasis is placed on reactant and fuel composition. The FSP processes are quite attractive as they can employ a wide array of precursors, so a broad spectrum of new nanosized powders can be synthesized. Computational fluid dynamics (CFD) in combination with gas-phase particle formation models offer unique possibilities for improvement and possible new designs for flame reactors.
Oxidation of Natural Gas, Natural Gas/Syngas Mixtures, and Effect of Burnt Gas Recirculation: Experimental and Detailed Kinetic Modeling

The oxidation of methane-based fuels was studied experimentally in a fused-silica jet-stirred reactor (JSR) operating at 1-10 atm, over the temperature range of 900-1450 K, from fuel-lean to fuel-rich conditions. Similar experiments were performed in the presence of carbon dioxide or syngas (CO/H 2 ). A previously proposed kinetic reaction mechanism updated for modeling the oxidation of hydrogen, CO, methane, methanol, formaldehyde, and natural gas over a wide range of conditions including JSR, flame, shock tube, and plug flow reactor was used. A detailed chemical kinetic modeling of the present experiments was performed yielding a good agreement between the modeling, the present data and literature burning velocities, and ignition data. Reaction path analyses were used to delineate the important reactions influencing the kinetic of oxidation of the fuels in the presence of variable amounts of CO 2 . The kinetic reaction scheme proposed helps understand the effect of the additives on the oxidation of methane.
The Importance of Thiosalts Speciation: Review of Analytical Methods, Kinetics, and Treatment

The presence of sulfuroxyion compounds (thiosalts) in mining wastewater is a concern because of their potential for acidification of receiving water bodies. Despite extensive research, generation and kinetic information of thiosalt species under different pH and temperature conditions is not fully understood, especially under the range of conditions likely to be encountered in receiving ponds. As a result, it is difficult to design ponds or develop treatment technologies to treat these compounds. The authors present a summary of relevant information in terms of generation and kinetics of thiosalts, analytical methods for measuring their concentrations, and treatment of thiosalt wastes.
Glycoalkaloid content of early potato varieties

Samples of Swedish domestic early potatoes were collected from whole-salers and analysed for their content of glycoalkaloids (GA), α-solanine and α-chaconine, using a modified HPLC procedure. The varieties included were, in order of increasing GA content; Maris Bard, Ukama, Provita, Evergood Eldorado, Maria, Early Puritan, Silla and Ulster Chieftain. The average total GA content (α-solanine and α-chaconine combined) for the different varieties ranged from 51 to 221 mg kg -1 fresh weight. α-Solanine constituted on average between 35 and 41% of the GA detected. The GA concentrations in individual samples were in the range 31-344 mg kg -1 . The variety Ulster Chieftain accounted for 88% of the samples above 200 mg kg -1 . The results obtained with tubers grown experimentally in field trials in two different years were consistent with the findings for commercially grown potatoes in terms of GA content rank among varieties
A novel method for sub-micrometer transverse electron beam size measurements using optical transition radiation

Optical Transition Radiation (OTR) appearing when a charged particle crosses a boundary between two media with different dielectric properties has widely been used as a tool for transverse profile measurements of charged particle beams in various facilities worldwide. The resolution of the monitor is defined by so-called Point Spread Function (PSF), source distribution generated by a single electron and projected by an optical system onto a screen. In this paper we represent the development of a novel sub-micrometre electron beam profile monitor based on the measurements of the PSF structure. The first experimental results are presented and future plans on the optimization of the monitor are discussed
Refolding molecular dynamics simulations of small- and middle-sized proteins in an explicit solvent

In order to elucidate the protein folding problem, we performed molecular dynamics simulations for small- and middle-sized two unfolding and six refolding proteins in an explicit solvent. Histidine-containing phosphocarrier protein and small designed protein were chosen for the simulations. We found that the protein folding process of these proteins was divided into three phases: an α -helix formation phase, a packing phase and a β -sheet formation phase. In the α -helix formation phase, an α -helix was developed from a β -turn structure through a 310-helix state. In the packing phase, proteins became compact, and tertiary structures (α / α or pre- β / β packing) were formed. Formation of a hydrophobic nucleus occurred concomitant with the α -helix formation and packing phase. Finally, in the β -sheet formation phase, a β -sheet was developed owing to the sequential formation of hydrogen bonds between two neighbouring strands, just like a "closing zipper".
Chapter One 1. Thermodynamics of Energy Transduction in Biological Membranes

1-1. Introduction Thermodynamics is a classical area of physics and chemistry for which there exists a large number of major treatises that form the background for this chapter. These include excellent treatises that emphasize the application of thermodynamics to problems in biochemistry and biophysics (Bloomfield, Biophysics Textbook On-Line ; Eisenberg and Crothers, 1979; Tinoco et al., 1978). Other sources are (Hill, 1966; Mahan, 1964; Chandrasekhar, 1957). The present treatment specifically emphasizes the application of thermodynamics to bioenergetics, or energy transduction in biological membranes. This energy transduction involves (i) the transduction of light and redox energy to "free energy" stored in a trans-membrane ionic electrochemical potential (∆µ ~ ), and (ii) the use of this energy to synthesize ATP and to drive active transport across
Electrochemical charging and photochemical discharging in heterodeposited polymer nanosheet assembly

We demonstrate electrochemical charge storage and photochemical release of the charge in heterodeposited polymer nanosheets assemblies. Two kinds of redox polymer nanosheets, those containing ruthenium dipyridyl complex (p(DDA/Rubpy32+)) and ferrocene derivative (p(DDA/Fc)), respectively were heterodeposited onto an ITO electrode using the Langmuir–Blodgett technique. The heterodeposited assembly forms a clear bilayer structure in which p(DDA/Rubpy32+) is located in an inner layer and p(DDA/Fc) in an outer layer. The electrochemical property of the heterodeposited assembly was studied by cyclic voltammetry measurement and compared with their single component film. The cyclic voltammogram of p(DDA/Rubpy32+) monolayer film showed a redox peak of Rubpy32+/3+ reaction around 1.1 V (vs.Ag/AgCl), and that of p(DDA/Fc) monolayer showed a redox peak of Fc0/+1 around 0.4 V. On the other hand, the cyclic voltammogram of the bilayer film showed no oxidation current around 0.4 V, and large oxidation currents were observed from 0.9 V. In the heterodeposited assembly, the p(DDA/Fc) layer was separated from the electrode about 5 nm by the inner p(DDA/Rubpy32+) layers. Therefore the oxidation of Fc moieties occurred by mediation of the inner p(DDA/Rubpy32+) layers, which started around 0.9 V. On the other hand, reduction of Fc+ by scanning the potential to cathodic direction was not observed, because reduction of Fc+ is thermodynamically unable for Rubpy32+. As the results, the outer p(DDA/Fc) layers store charges as Fc+ by one potential cycle (electrochemical charging). Moreover, we demonstrate the Fc+ reduction by using the photoinduced electron transfer from an excited ruthenium complex to Fc+ (photochemical discharging). The repeatability of the charging-discharging process was about 5 times. To improve the repeatability, Prussian blue (PB) nanoparticles were used instead of the p(DDA/Fc) layers. PB nanoparticles were assembled on a solid substrate using a cationic polymer nanosheet, poly(N-dodecylacrylamide-co- N-(2-(2-(2-aminoethoxy)ethoxy)ethyl)acrylamide) (p(DDA/DONH)) as a template. A hybrid heterodeposited assembly was prepared using p(DDA/Rubpy32+) as an inner layer and p(DDA/DONH) templated PB as an outer layer. The hybrid heterodeposited assembly stored and released charges by a similar process with the p(DDA/Rubpy32+)-p(DDA/Fc) heterodeposited polymer nanosheets assembly. The repeatability of the charging-discharging process in the hybrid heterodeposited assembly was increased compared to that in the p(DDA/Rubpy32+)-p(DDA/Fc) heterodeposited assembly due to the high stability of the oxidized form of PB. The high repeatability of the hybrid heterodeposited assembly indicates that the assembly is applicable to molecular-memory and battery.
Micro-structure and hydraulic conductivity of simulated sand-bentonite mixtures

This paper describes the relationship between the micro-structure and hydraulic conductivity of simulated sand-bentonite mixtures (SSBMs) prepared with powdered and granular bentonite. Glass beads were used to simulate sand grains because of their superior optical properties. The micro-structure of SSBMs was observed using optical micrography and scanning electron microscopy. For mixtures prepared with powdered bentonite, the indications are that bentonite coats the particles. As the bentonite content increases, the thickness of bentonite coating increases and reduces the area available for flow. For mixtures containing granular bentonite, the dry bentonite granules occupy the space between the particles and then swell to fill the void space. As the bentonite content increases, the number of granules increases, leading to more void spaces being filled with bentonite. At higher bentonite content (>8%), flow paths devoid of bentonite are unlikely, and the hydraulic conductivity appears to be controlled by the hydraulic conductivity of bentonite. The changes in micro-structure that were observed are consistent with the decrease in hydraulic conductivity that occurs with increasing bentonite content. However, the relationship between hydraulic conductivity and bentonite content differs depending on whether a mixture contains powdered or granular bentonite.
Prediction of the θ(UCST) of Polymer Solutions: A Quantitative Structure-Property Relationship Study

One of the industrially important thermodynamic properties of polymer solutions is the upper critical solution temperature at the limit of infinite chain length of polymers, which is used to realize the usage limits of polymer solutions; this property is denoted as the θ(UCST). In this study, the quantitative structure-property relationship technique (QSPR) was used to correlate the θ(UCST) of polymer solutions. Based on molecular descriptors calculated from the chemical structures of the polymer and the solvent, a nine-parameter multilinear equation was obtained. This correlation can predict the θ(UCST) of 107 polymer solutions with a mean relative error of 6.12% and squared correlation coefficient of 0.912.
The Time Evolution of Interactions Between Ultra Short Length Scale Pressure Distrubances and Premixed Flames.

Abstract The non-linear wave equation governing the progress of short length scale pressure perturbations across a conventional premixed flame is solved numerically. The particular acoustic disturbances considered have length scales of the same order as that of the flame and fractional amplitudes limited to O(l/θ), where θ is the dimensionless activation energy. These restrictions imply that the effects of the reaction and diffusion processes within the flame are negligible over the time scale of the passage of the pressure signals. The length scale of such a disturbance is of the order of a typical diffusion length, so the spatially varying temperature and density profile within the preheat and reaction zones must be considered (McIntosh 1989, McIntosh and Wilce 1991). However, in this work the exact steady temperature distribution, generated numerically, is used in the hyperbolic governing equations, enabling disturbances with length scales near to those of shock waves to be considered. Shock formation .
A Ruthenium(II)‐Complexed Rotaxane Whose Ring Incorporates a 6,6′‐Diphenyl‐2,2′‐bipyridine: Synthesis and Light‐Driven Motions

By incorporating a 6,6'-diphenyl-2,2'-bipyridine (dpbipy) fragment in a ring, endo coordination of a ruthenium(II) center is performed selectively and almost quantitatively. The threaded system, containing a helical fragment, could be fully characterized. When the terminal functions of the rod-shaped helical complex threaded through the macrocycle are phenol groups, the complete rotaxane is prepared by the classical Williamson stoppering reaction in moderate yield. Light-induced motions of the unstoppered system (pseudorotaxane) and the real rotaxane have been studied. Under visible light irradiation, quantitative decoordination of the dpbipy-containing ring is observed, leading to the separate fragments (ring and helical thread) or to a new rotaxane (uncoordinated ring threaded by the dumbbell). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
A rapid method for the determination of fixed ammonium in soil

Abstract Five different procedures for the oxidation of organic carbon were compared in order to determine the most suitable method for use as a pretreatment before the determination of fixed NH4‐N in soils. Three of the procedures involved a method based on the use of a solution containing 0.1M Na4P2O7, 0.1M NaCl, and 6% H2O2, applied for three different periods of time, 10 days, 20 days, and whatever number of days are required until frothing no longer occurs. This third period of time is designated as NF (no frothing). The remaining two procedures involved a method based on the use of a 3M NaOCl solution applied for two different periods of time, 3‐cycles and 5‐cycles. Two of the procedures, the NF treatment with H2O2+NaCl+Na4P2O7 and the 5‐cycle treatment with NaOCl, were found to give the must efficient removal of organic C. The amount of residual N in the soil after the NF treatment was highly correlated with the amount of residual N in the soil after the 5‐cycle treatment. It is concluded that the .
Reaction of Vanadium Compounds with Ceramic Oxides

This communication reports a study of the reactions of Y/sub 2/O/sub 3/, CeO/sub 2/, and ZrO/sub 2/, and also of GeO/sub 2/ and Ta/sub 2/O/sub 5/-which were chosen (see below) as examples of oxides more acidic than the initial three-with V/sub 2/O/sub 5/, NaVO/sub 3/, and Na/sub 3/VO/sub 4/. The reactions were investigated with the reagents simply as mixtures of the pure compounds and, also, in selected cases, with the reagents mixed with Na/sub 2/SO/sub 4/ and exposed under partial pressures of 40-110 Pa of SO/sub 3/, to better simulate gas turbine conditions. The ultimate goal was to provide information that might help to better understand the reactions Y/sub 2/O/sub 2-/ and CeO/sub 2-/ stabilized ZrO/sub 2/ thermal barrier coatings in gas turbines burning vanadium-contaminated fuel.
Laccase from Basidiomycetous Fungus–Catalyzed Synthesis of Substituted Benzopyranocoumarins via Domino Reaction

Abstract The present investigation provides a simple and convenient route to organic synthesis of substituted benzopyranocoumarin, which is important because it is a probable HIV protease inhibitor. The reaction of α,β-unsaturated derivatives of coumarins with catechol or 1,4-hydroquinones was catalyzed using laccase in an aqueous medium. Quinones, generated in situ by the oxidation of the corresponding catechol or 1,4-hydroquinones, underwent a domino reaction with chalcones to produce benzopyranocoumarins.
AIR BAKE-OUT TO REDUCE HYDROGEN OUTGASSING FROM STAINLESS STEEL

Hydrogen outgassing is the most significant factor limiting the attainment of outgassing rates below 10−12 mbar l s−1 cm−2 in stainless steel vacuum systems. This limit turns out to be crucial in very large vacuum systems, like the VIRGO vacuum tubes (2 tubes 1.2 m diam, 3000 m length). Heating the raw material at 400 °C in air was suggested as a money saving alternative to the classical vacuum heating at 950 °C. We report the results of hydrogen content analysis performed on stainless steel samples submitted to different treatments, and also the measurement performed on a prototype tube (1.2-m-diam, 48-m-long). We concluded that air bake-out drives out most of the hydrogen absorbed in the bulk stainless steel, while the presence of an oxide layer does not reduce the hydrogen outgassing.
Free radical scavenging activity of Smilax wightii a. DC. (Smilacaceae), an endemic medicinal plant from Western Ghats.

The present study was aimed to evaluate the free radical scavenging activity of methanol extract of Smilax wightii by using DPPH, Nitric oxide and ABTS radical scavenging assays. The extract had scavenging activities on DPPH radical in a dose-dependent manner with an IC50 value of 31.68 µg/ml. The extract showed its highest nitric oxide radical scavenging activity 95.16% in 50 µg/ ml. A steady increase in the percentage inhibition of the ABTS radicals by extract was observed in 872.52±0.08 trolox equivalence in μMol/g extract at the dose of 50 μg/ml. The results suggest that the methanol extract of S. wightii has very strong antioxidant activities and could be used as effective natural antioxidant resources.