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Theoretical investigation on the solubility of C-impurity in AB and AB3 alloys with hexagonal close-packed lattices of different structures has been carried out by the method of configurations in approaching the pair interaction of the nearest atoms. It is supposed that impurity atoms are located in octahedral and tetrahedral interstitial sites. The solubility dependence on alloy composition, temperature and order parameter has been defined. Comparison of the theoretical results with experimental data on the concentration and temperature dependence of hydrogen solubility shows good agreement between theory and experiment for PdPt-H, FeV-H, PdNi-H, Ni3Fe-H alloys. The theoretical calculation of hydrogen solubility in ordering bcc and fcc crystals of fullerites has been performed by the method of average energies and configuration method, i.e., taking into consideration the possibility of realization of different configurations of C60, C70 fullerenes around interstitial sites of various types, under the assumption of geometrical ideality of crystal lattices, with regard to the ordering of C60, C70 fullerenes on lattice sites and hydrogen atoms arrangement in interstitial sites of different types. The equilibrium concentrations of hydrogen atoms in interstices of all types and then the total solubilities of hydrogen in bcc and fcc fullerites have been found from conditions of free energies minimization. The dependences of hydrogen solubilities in bcc and fcc fullerites on temperature, fullerite composition, long-range order, hydrogen atoms activity, and energetic constants have been ascertained. [ABSTRACT FROM AUTHOR]

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]