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The present paper aim was the investigation of the electrodeposition regimes influence on the structure and hydrogen permeation of the nickel films under 4 mcm thickness of, received from sulphamate electrolyte. The grain size was calculated and the histograms, characterized the grains distribution with their size, were built according the nickel deposits microstructures photographs. The microtensions values, the mosaic blocks size and the quantitative porosity magnitude were also established. [ABSTRACT FROM AUTHOR]

The influence of mechanical grinding and alloying due to high energy ball milling upon the decomposition temperature and thermal stability of hydride phases of systems Ti-B-H, Y-H, Mg-Fe-H have been investigated. [ABSTRACT FROM AUTHOR]

The thin-film protective coat of titanium nitride (TiN) plotted to stainless steel (brand 12X18H10T) is explored. The mathematical model and methods of parametric identification are described. Kinetic parameters of hydrogen permeability through stainless steel membrane with TiN protective coat are determined. [ABSTRACT FROM AUTHOR]

The magnetic properties (magnetic ordering temperature and magnetization) of the ferrimagnetic compounds R2Fe14B (R = Gd, Tb, Dy, Ho and Er) and their hydrides R2Fe14BH2.5 were studied. It was found that incorporation of hydrogen into the crystal lattice of R2Fe14B compounds substantially increases the Curie temperature and Fe-Fe exchange interactions. Hydrogenation does not practically change the intersublattice exchange field h21 and exchange field h22 within the R - sublattice. This effect can be understood as a result of the attendant changes in the unit cell volume and an electronic structure of these compounds. [ABSTRACT FROM AUTHOR]

This work deals with a concept for the development of the autonomous wind-hydrogen stations transforming the primary energy of wind into environmentfriendly energy carrier, hydrogen, and oxygen as a by-product. [ABSTRACT FROM AUTHOR]

article approaches to optimization of HHP operation as heat machine are planned. Optimization is directed on achievement of the maximal efficiencies, coldproductivities or levels of temperatures. Optimization of weight and the sizes of tubular sorbers are possible. The question of the coordination of a heat emission in hydride beds and heat exchangers is especially important. To increase efficiency of HHP it is possible, both by a choice of the best hydrides, and by optimum control in regime parameters of HHP. The mathematical modelling spent both a method enumeration of possibilities, and a regression procedure analysis, testifies to extreme behaviour of regime parameters of HHP. [ABSTRACT FROM AUTHOR]

In present work we have investigated the reduction of oxygen at polyaniline (PANI) type electroconducting polymers (ECPs) and its composition with thermally exfoliated graphite (TEG). To explain the reasons of the catalytic activity of ECPs, a quantum-chemical modeling of ECPs and adsorption complexes of ECPs with oxygen has been performed. [ABSTRACT FROM AUTHOR]

Some ideas put into designing of the basic MHHP device - a hydride reactor-sorber - are traversed in the report. Features of hydride beds are considered from the point of view of hydrogen filtration and heat exchange improvement. Designs of two sorbers - modular and monoblock are described and their effective thermal conductivity and heat transfer are evaluated. Results of experimental determination of effective thermal conductivity of hydride bed with the heatconducting corrugated insertion are given. Parameters of installations tested with developed sorbers are briefly presented. Approaches and some results of mathematical modelling MHHP processes are presented. Achieved experimental characteristics are compared for different sorbers. It is shown that a modular sorber takes precedence over monoblock one because of essentially greater heat exchange surface. [ABSTRACT FROM AUTHOR]

The way of reception ultradispersed of educations of free carbon in iron alloys is developed. The way is based on local melting by the concentrated sources of energy. The mechanism of formation ultradispersed of educations of free carbon is described and the influence them on properties of alloys are determined. [ABSTRACT FROM AUTHOR]

Influence of thermoplastic treatment conditions in various corrosive media on tendency of maraging steels to delayed fracture has been investigated. Parameters of the treatment that are optimal for the improvement of the structural strength of steels have been determined. [ABSTRACT FROM AUTHOR]

Equilibrium geometry parameters, total energies, heats of formation, energies of HOMO and LUMO orbitals, and density of one-electron states for some nanotubes Y-junctions of twig types are computed in the frames of semi-empirical quantum chemistry PM3-method. [ABSTRACT FROM AUTHOR]

In frameworks of semi-empirical PM3-basis equilibrium configurations, total energy, heat of formation, energies of HOMO and LUMO orbitals, density of oneelectron states (DOS) of open (12,0) carbon nanotubes with local vacancies and defects are obtained. [ABSTRACT FROM AUTHOR]

The chemisorption problem of a single fluorine atom on the outer surface of zigzag single-walled carbon nanotubes (SWCNTs) is treated within the Anderson-Newns approach, which takes account of the intra-atomic electron interaction on the adatom. [ABSTRACT FROM AUTHOR]

The individual regioisomers of bis(organo)-[C60]fullerenes were synthesized by the reactions of fullerene C60 with isocyanurato- and nitropyrimidino-substituted azides. The structures of the regioisomers were determined by 13C and 1H NMR, IR and UV spectroscopy. It was shown that regioselectivity of the azides addition to fullerene framework depends on organic fragment bulk and the conjugations between organic and fullerene fragments in bis(organo)-[C60]fullerene molecules. [ABSTRACT FROM AUTHOR]

In present work we investigate the treatment of UDD powder in a hydrogen atmosphere and during sintering of the powder both in the as-delivered condition and after annealing in hydrogen. Features of the evolution of structural reconstruction in the system of UDD particles during sintering were elucidated. [ABSTRACT FROM AUTHOR]

It is shown that reinforcement of PTFE by 15% of multiwall carbon nanotubes (MWNT) results in more than 2 times increase of strength parameters compared to starting PTFE matrix. Non-trivial temperature dependences of electrical resistance and thermal electromotive force were observed. Percolation threshold determined from dependence of the composite specific resistance on MWNT concentration was near 6% mass. Concentration and nature of oxygencontaining MWNT surface groups influence the strength parameters of the composite material. [ABSTRACT FROM AUTHOR]

The constructive and technological features of silicon electrodes of polymer electrolyte membrane fuel cell (PEMFC) are discussed. Electrodes are made with application of modern technologies of integrated circuits, and technologies of macroporous silicon. Also ways of realization of additional functionalities of electrodes to offered constructive - technological performance are considered. [ABSTRACT FROM AUTHOR]

Free-volume structure in the lanthanum salt of laurinic acid in crystalline and liquid-crystalline states and an effect of dissolved C60 molecules on the mean nanovoid radius and concentration were studied by means of the positron annihilation technique. La(C12H25COO)3 clathrate compound with dissolved C60 molecules was obtained, which is thermodynamically more stable than a simple mixture of components. Increased mean nanovoid radius (from 0.28 to 0.39 nm) after the inclusion of C60 molecules and concomitant decrease of the positronium annihilation rate by a factor of 2.7 indicate the decrease of the smallest nanovoid concentration. [ABSTRACT FROM AUTHOR]

We report on the investigation of some carbon structures fabrication in the discharge arc. The formation of a cathode deposit in the form of a cylinder at all the used argon pressures is usually observed. It is shown that the ledge-deposit mostly has been consisted of the spherical particles coagulating in the form of filaments. The X-ray diffraction of a ledge-deposit showed only the characteristic peaks of hexagonal graphite. A metallic foil being put in the discharge chamber is covered with some colourless thin needle-like plates. The X-ray diffraction of these plates showed the peaks of hexagonal α - carbine. [ABSTRACT FROM AUTHOR]

Structure changes in amorphous phases of different modifications of carbon (diamond, graphite, fullerene) have been investigated by means of neutron and x-ray diffraction under irradiation and pressure. Polyamorphic transition (diamond-like - graphite-like phases) was found in irradiated diamonds by density change. It is shown that radiation amorphization of graphite might be connected with softening of the vibration modes at volume increasing. Polyamorphic transition has been established in amorphous fullerenes at high temperature annealing after radiation or ball milling amorphization. [ABSTRACT FROM AUTHOR]

The membrane catalysts possess a selective permeability for one of the reagents. The carbon materials got the increasing value in processes of membrane for gas separation due to their high selectivity and permeability, high hydrophobicity and stability in corrosive and high-temperature operations. At the same time carbon materials are widely known supports of metal catalysts. The present work is the first sample of development of the methods of preparation of carbon membrane catalysts with metal nanoparticles in a carbon membrane matrix. The other granulated rhenium-carbon catalyst was obtained for the first time by high-temperature destruction of copolymers. It is shown, that both catalysts are active in hydrocarbons dehydrogenation and demand considerably the smaller maintenance of metal, than the traditional catalysts put on coal, with other things being equal. [ABSTRACT FROM AUTHOR]

Equilibrium configurations, total energies, heats of formation, energies of HOMO and LUMO states, densities of one-electron states (DOS) and IR spectra of CNTs T-junctions of the various types are calculated by employing of PC Gamess version of semi-empirical quantum chemistry PM3-method. [ABSTRACT FROM AUTHOR]

Geometrical parameters, total energy, heat of formation, energies of HOMO and LUMO orbitals, density of one-electron states (DOS) are determined by using of semi-empirical quantum chemistry PM3-method for isolated molecules Cn, dimers (Cn)2 and cuban-like clusters (Cn)8 for n = 20, 24, 28, 32. The results of calculations allow assuming the existence of polymerized cubic crystal structure on base of all considered small fullerenes. [ABSTRACT FROM AUTHOR]

Equilibrium configurations, total energy, heat of formation, energies of HOMO and LUMO orbitals, density of one-electron states (DOS) of open and semi open carbon nanotubes of variable diameter such types as (6,6)+(6,0), (5,5)+(5,0) and (6,0)+(5,0) are determined in frames of semi-empirical quantum chemistry PM3-method. [ABSTRACT FROM AUTHOR]

In the present work it is for the first time proposed to use a photoelectrochemical cell with a GaAs photoanode and a metal hydride cathode based on intermetallic alloys LaNi5-xCox, where 0≤x≤2.5 for solar-to-hydrogen conversion with possibility to storage hydrogen in a cathode material. The characteristics of photoanode and cathodes have been investigated and results obtained are discussed. [ABSTRACT FROM AUTHOR]

The use of mechanical activation is shown to be efficient for decrease of the temperature of titanium hydride decomposition and its interaction with nitrogen. Intense milling of titanium hydride TiH1.89 results in partial loss of hydrogen and formation of TiH1.68, which in the presence of nitrogen completely transforms into titanium nitride at 500 °C. Under heating in a nitrogen atmosphere, reaction of intramolecular oxidation-reduction takes place at the expense of oxygen absorbed by mechanically activated powder with yielding lower oxide Ti2O. [ABSTRACT FROM AUTHOR]

A method for analysis of experimental dynamical curves of hightemperature vacuum-extraction is developed, which allows determining the binding energy and diffusion constants of hydrogen in the probe under study. The experimental data have been obtained using the measuring complex, which allows conducting the absolute measurements of the dynamical curves of high-temperature vacuum- extraction of hydrogen from a solid probe. [ABSTRACT FROM AUTHOR]

The present work is devoted to research of influence anion impurity (B, C, N, O, F, Ne) on binding energy of hydrogen of hydroxyl group of bridge type on surface zirconia nanocrystal particle and energy of dehydration molecule of water of bridge type with its surface. The analysis of results quantum-mechanical modelling of processes dehydrogenation and dehydration is carried out within the framework of the theory of the SPD-connected systems. [ABSTRACT FROM AUTHOR]

The photocatalytic reduction of metal cations (M = Ni2+, Co2+, Cu2+, Cd2+, Zn2+, Fe2+, Ag+, Pb2+) on the surface of mesoporous TiO2, synthesized by solgel technique, was found to cause formation of nanostructured metalsemiconductor composites TiO2/M. [ABSTRACT FROM AUTHOR]

This work aim was the researching on the hydrogen penetration into the Ni and Ni-B coatings and on the electrodeposition regimes correlation. The investigations were carried out in the sulfamate nickelling electrolyte with the polyhedral borates class dope. The pH, cathodic current density, electrolyte temperature and alloy boron concentration effects on the hydrogen consumption were studied. The experimental data analysis represented the lower hydrogen consumption in the Ni - B alloy, than in the Ni coating at the same electrolysis regimes. [ABSTRACT FROM AUTHOR]

Magnetic properties of the Lu2Fe17 single crystal and its hydride Lu2Fe17H1.5 have been studied by means of magnetization and magnetostriction measurements. An unusual magnetic behavior with two magnetic phase transitions has been observed in the host compound. It was found that hydrogenation leads to suppression of antiferromagnetism and induction of the ferromagnetic state with a high Curie temperature (TC = 393 K). The hydrogenation exerts a significant influence on magnetoelastic properties of the Lu2Fe17 single crystal: a thermal expansion along the c-axis becomes positive, magnetostrictive deformations decrease. [ABSTRACT FROM AUTHOR]

Activated carbons were chosen as an efficient hydrogen sorption materials to design gas storage systems. Based on experimental data empirical dependences for choosing commercially available carbon hydrogen sorbents systems were proposed. To increase gas sorption capacity technology of carbon additional activation was applied. [ABSTRACT FROM AUTHOR]

In the paper we consider the problems with moving bound that model the kinetics of hydrogen desorption from hydrides of metals. Change of phase, desorption processes and size reduction effect are taken into consideration. Equations are derived at various assumptions for the experimental method of thermal desorption spectrometry. As the high-temperature TDS-spectra peaks are considered, the diffusion may be assumed to be fast. Therefore ordinary differential equations are sufficient. We present the results of numerical experiments for the models with bulk and surface desorption. [ABSTRACT FROM AUTHOR]

With the purpose of a solution of a problem of obtaining of firm hydrogen, the analysis of characteristics of known intensifiers and hydraulic presses for synthesis at high specific pressure of some simulated stuffs, for example of diamonds is executed. The matching of the characteristics of known rigging and equipment with idealized parameters of obtaining of metallic hydrogen has allowed to draw a conclusion that the existing means are not suitable for the solution of the given problem. The writers are offered and described the new original designs of an intensifier and presses, free from lacks known and, in case of implementation them in the metal suitable for a positive solution of the given problem. [ABSTRACT FROM AUTHOR]

Magnetic properties of intermetallic compound Er2Fe14B and its hydrides Er2Fe14BHx have been investigated. Measurements of the temperature dependencies of magnetization have been performed with the permanent control of the hydrogen content in the investigated samples. The dependencies of Curie (TC) and spinreorientation transition (TSR) temperatures on the hydrogen pressure and concentration of the inserted hydrogen atoms in the crystal lattice have been determined. Reasoning from the experimental data for TSR, TC and exchange parameters, the crystal field parameters and their change with the concentration of the inserted hydrogen atoms have been calculated. [ABSTRACT FROM AUTHOR]

Gamma-ray radiation induced change in the electrical conductivity of the proton-conducting polymer, perfluorosulfonic acid membrane, was investigated. The electrical conductivity increased with increasing the absorption dose in linear form at 300 K and hereafter gradually increased up to be higher by about three orders of magnitude. The conductivity greatly depended on the humidity in vacuum or air. Moreover it was observed by optical absorption measurement that radiation induced defects such as fluorocarbon and peroxy radicals and C=O groups increased with increasing the dose. Therefore, the increase of the conductivity is attributed to conduction due to protons produced by absorption of H 2O with the radiation induced defects. [ABSTRACT FROM AUTHOR]

IR pyrolysis of PAN and PAN based composites yields ordered graphitelike structure as well as several carbon nanostructures. Metal-carbon nanocomposites, in which the nanosized metal particles were introduced into the structure of carbon matrix in the course of IR pyrolysis of composite-precursor on the basis of PAN and metal (Gd, Pt, Ru, Re) compounds were prepared. The carbon phase of metal-carbon nanocomposites was shown to include different types of nanostructured carbon particles. [ABSTRACT FROM AUTHOR]

The relationship of hydration properties of carbon nanoparticles in aqueous dispersions and stability of these dispersions with respect to aggregation have been studied using EPR spin probing of frozen dispersions. Aqueous dispersions of shungite carbon nanoparticles at different concentrations and aqueous colloids of fullerenes C60/C70 have been compared. Characteristic features of the bounded water have been shown to correlate with a decrease of aqueous dispersions stability to aggregation. [ABSTRACT FROM AUTHOR]

Films of zirconia-based solid electrolytes were prepared by the ionplasma sputtering method. Scanning and transmission electron microscopy methods were used to analyze their structure and processes of their formation. It was found that films of ZrO2 - Y2O3 and ZrO2 - Sc2O3 systems had a nanocrystalline structure. The zirconia-based films were characterized by a columnar structure. A model describing the formation of pores and submicropores during the growth of films of ZrO2 - Y2O3 and ZrO2 - Sc2O3 systems was proposed and discussed. [ABSTRACT FROM AUTHOR]

Adsorption isotherms of pure hydrogen and deuterium on samples of nanoporous carbon (NPC) have been determined at range of temperature 67-78 K. Distinction in sorption abilities of nanosorbent in relation to deuterium and to hydrogen has been fixed. Adsorption capacity of the NPC samples relative to deuterium in range of pressure 0-100 kPa is larger than one to hydrogen, and both values are considerably larger than values of hydrogen isotopes adsorption capacity on common sorbents such as zeolites and active carbons. [ABSTRACT FROM AUTHOR]

The experimental results and also results of industrial tests on realization of the catalytic conversion of the natural gas in a warmed pipe with the purpose of reception of a gas mix of CO and H2 without H2 and CO2 are presented. This mix are called as technological gas or synthesis-gas or regenerative gas - depending of using method. The reaction CH4 + H2O = 3 H2 + C (1) was carried out in stoichiometric ratio or with the ratio close to stoichiometric (H2 O/CH4 <1.5). Technologies and outline descriptions of designs of corresponding devices are presented. [ABSTRACT FROM AUTHOR]

The object of this work was to investigate hydrogen oxidation and oxygen reduction from surface of modified nanodispersed diamond. The catalytic reactions on the surface of nanodispersed diamond have been studied after different treatment using heat-treated and electrochemical methods. [ABSTRACT FROM AUTHOR]

Diffusion of gases in titanic powders depends on a way of manufacture, the conditions of lixiviation at hydrometallurgical processing of powders, and also on a condition and on the structure of the surface of particles. The different methods to investigate products of corrosion, as on a surface of particles, and in the fulfilled solutions in which the tests are performed, are given. The correlation between them is established. The influence of oxygen on formation of hydrides is shown. The recommendation for use titanic powders saturated by gas is given. [ABSTRACT FROM AUTHOR]

Nanocarbon materials and method of their production, developed by TMSpetsmash Ltd. (Kyiv, Ukraine), are reviewed. Multiwall carbon nanotubes with surface area 200-500 m2/g are produced in industrial scale with use of CVD method. Ethylene is used as a source of carbon and Fe-Mo-Al- mixed oxides as catalysts. Fumed silica is used as a pseudo-liquid diluent in order to decrease aggregation of nanotubes and bulk density of the products. Porous carbon nanofibers with surface area near 300-500 m2/g are produced from acetylene with use of (Fe, Co, Sn)/C/Al2O3-SiO2 catalysts prepared mechanochemically. High surface area microporous nanocarbon materials were prepared by activation of carbon nanofibers. Effective surface area of these nanomaterials reaches 4000-6000 m2/g (by argon desorption method). Such materials are prospective for electrochemical applications. Methods of catalysts synthesis for CVD of nanocarbon materials and mechanisms of catalytic CVD are discussed. [ABSTRACT FROM AUTHOR]

Carbon nanostructures were prepared by the carbonization of polystyrene, which was introduced as solutions into fumed silica based composites-matrices. Composite-matrices were impregnated with polystyrene solutions, or the latter were used as a dispersion medium at the stage of forming the composite-matrix. The precursor was carbonized at 750 °C in an argon stream. It has been found that the structure of the carbon formed depends both on the method of introducing the precursor into the composite-matrix and on the conformation of polystyrene macromolecules in the solution. When impregnating with polystyrene solutions, carbon tubes of different diameter (of up to 320 nm) or aggregates of up to 100 nm particles are formed in composite pores after carbonization. When polystyrene solutions are used as a dispersion medium, carbon structures in the form of segmented spheres (60 nm), "shells" (up to 100 nm in diameter) and aggregates of up to 100 nm particles are formed after polystyrene carbonization. The composition of the carbon formed was determined by XPS. [ABSTRACT FROM AUTHOR]

At present stage of development of carbon nanomaterial production technologies the great attention is paid to the creation of the equipment which allow obtaining these materials in significant amounts. [ABSTRACT FROM AUTHOR]

A chemical composition and structural parameters of specially prepared catalyst for the pyrolytic synthesis of carbon nanomaterials have been studied by X-ray diffraction, Mossbauer spectroscopy and electron microscopy. A plenty of chemical transformations in the catalyst have been monitored. The inert (Mg1-X FxO) and active, very fine particles of the catalyst (MgFe2O4) components which are involved in the process of carbon nanofibers were revealed. [ABSTRACT FROM AUTHOR]

Single crystals of TbFe11-xCoxTiHy (x = 5; y = 0, 1) with the tetragonal ThMn12-type structure were obtained. Magnetisation measurements along main crystallographic directions of TbFe6Co5TiHy (y = 0, 1) single crystals have been performed in the temperature range 5-340 K. It was established that TbFe6Co5Ti compounds show "easy axis" anisotropy in whole temperature range below Curie temperature (TC). It was concluded that hydrogenation leads to an increase of magnetic anisotropy, and TbFe6Co5TiH hydride demonstrates "easy plane" anisotropy with the easy axis oriented along the [100] crystallographic direction. It was found that the replacement of the Fe by Co and hydrogen insertion into the crystal lattice of Tb(Fe,Co)"11"Ti compounds have an opposite influence on the magnetocrystalline anisotropy. [ABSTRACT FROM AUTHOR]

Calculations of the non-linear wave functions of electrons in single wall carbon nanotubes have been carried out by the quantum field theory method namely the second quantization method. Hubbard model of electron states in carbon nanotubes has been used. Based on Heisenberg equation for second quantization operators and the continual approximation the non-linear equations like non-linear Schroedinger equations have been obtained. Runge-Kutt method of the solution of non-linear equations has been used. Numerical results of the equation solutions have been represented as function graphics and phase portraits. The main conclusions and possible applications of non-linear wave functions have been discussed. [ABSTRACT FROM AUTHOR]

DHC velocity in Zr-2.5%Nb alloy for different hydrogen concentrations were investigated using specimens prepared from the both CANDU and RBMK Zr- 2.5%Nb fuel channel pressure tube material. Sections of the pressure tube were hydrided to produce hydrogen concentration up to 72 ppm using an electrolytic method and diffusion annealing treatment From hydryded pressure tube material compact toughness specimens were made. Axial cracking velocity was determined on fatigue pre-cracked specimens under constant loading and initial KI value of 15 MPa˙m½. [ABSTRACT FROM AUTHOR]