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The comparative analysis of the kinetics of the bulk crystallization of AsSe1.5Bix glasses (х = 0, 0.01, and 0.05) in the temperature range 210–260°C is conducted by the data of density measurement using the generalized Kolmogorov–Avrami equation and the results of phase and differential thermal analysis. The kinetics of the surface crystallization of As2Se3 glass containing 0.4 at % Bi at 270 and 310°C and the parameters of the specific electrical conductivity and microhardness of the quenched semiconducting glass-ceramics at different stages of thermal treatment are studied.

The physicochemical and catalytic properties of 6%Ni/Al2O3 catalysts in the gas-phase hydrodechlorination of chlorobenzene (CB) are studied. The catalysts are synthesized by supporting nickel nitrate on two types of alumina—A (synthesized by aluminum isopropoxide hydrolysis) and E (manufactured by Engelhard)—with different morphologies and textures; some of the samples are unmodified, and some are modified by depositing 20% heteropoly acid (HPA) H8Si(W2O7)6 ⋅ nH2O. To prevent the HPA from decomposition, the air calcining and reduction of the modified materials are conducted at relatively low temperatures (250 and 330°C, respectively). To provide an adequate comparison, the catalysts containing no HPA are subjected to a similar treatment. Temperature-programmed reduction (TPR) reveals that air calcining at 250°C does not provide the complete conversion of the original nickel nitrate to oxide; nickel nitrates and hydroxynitrates are present in the catalyst precursors; their content decreases upon modification with the HPA. Differences in the composition and strength of Lewis acid sites on the surface of two types of Al2O3 lead to dissimilar coordination of nitrate and differences in nickel reducibility, as revealed by TPR, diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy with CO adsorption, and in situ X-ray photoelectron spectroscopy (XPS). Nickel contained in Ni/Al2O3(E) undergoes reduction somewhat more readily than nickel in Ni/Al2O3(A) does; however, the conditions used in this study provide the reduction of only a small portion of nickel in the two catalysts. According to in situ XPS, TPR, and DRIFT spectroscopy with CO adsorption, the modification of Ni/Al2O3 with the HPA leads to a further change in the acidic properties and the coordination of nickel nitrate during impregnation and an increase in nickel reducibility; it prevents nickel from migration from the surface into the bulk of the sample and leads to the formation of new active sites owing to the strong nickel–tungsten interaction in the HPA. Depending on the nature of the support, modification with the HPA leads to an improvement (Ni/HPA/Al2O3(A)) or deterioration (Ni/HPA/Al2O3(E)) of the catalytic efficiency of the samples. At high temperatures, the benzene selectivity of the HPA-modified catalysts decreases owing to the formation of cyclohexane. The catalyst efficiency increases in the following order: Ni/HPA/Al2O3(E) < Ni/Al2O3(A) < Ni/Al2O3(E) < Ni/HPA/Al2O3(A). The most active catalyst—Ni/HPA/Al2O3(A)—exhibits the highest stability in long-term tests with an increase and subsequent decrease in temperature. The effect of nickel reducibility on the catalyst efficiency in CB hydrodechlorination is more significant than the effect of differences in texture and nickel content.

A model is proposed for intensification of the process of high-temperature vacuum removal of iron impurities from microporous aluminum oxide via purging of the particle layer with argon. In the temperature range characteristic of this process, the pressure of saturating vapors above pure iron is on the order of 0.1 mm Hg. For an impurity with a concentration of several particles per million, the figure is proportionally smaller, and this creates problems with evacuation of the chamber. The use of argon as a carrier gas destroys the rigid connection between the partial vapor pressure of the impurity and the pressure in the vacuum chamber. Calculations show that the argon flow under moderate vacuum 10–5 mm Hg with a mass flow rate on the order of 10–7 kg/(m2 s) provides a very deep purification.

Catalytic systems 2 wt % Pd/Al2O3 were prepared using noncalcined boehmite (NC) and two types of alumina support: one was prepared by the calcination of boehmite at 600°C (C) and the other produced by Engelhard (E). To prepare 2 wt % Pd/HPC–Al2O3 samples, these supports were modified by impregnation by a heteropoly compound (HPC) (20 wt % Н8[Si(W2O7)6] ⋅ 6Н2О). The effect of the Al2O3 structure and its modification by the heteropoly compound on the physicochemical properties, activity, selectivity and stability of catalysts in the reaction of multiphase hydrodechlorination of 1,3,5-trichlorobenzene (TCB) was studied. All catalysts showed activity in the considered reaction with the predominant formation of benzene but were deactivated in the reaction medium. Modification by the heteropoly compound resulted in increased stability and was especially effective for catalyst supported on Al2O3(E). The method of scanning electron microscopy (SEM) was used to determine the morphological differences of supports. According to the data of transmission electron microscopy, all catalysts contained palladium in the form of particles less than 20 nm in size. The particle size and width of the size distribution increases in the series Pd/Al2O3(NC) < Pd/Al2O3(C) < Pd/Al2O3(E). Modification by the heteropoly compound was favorable for the decrease in the size of palladium particles. The method of temperature-programmed reduction with hydrogen (TPR-H2) showed that all catalysts included in their composition palladium hydride along with more strongly surface-bound metal forms that are reduced at elevated temperatures, and their content decreases after modification by the heteropoly compound and increases after catalytic tests. According to diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), the deposition of a heteropoly compound leads to a change in the type of Lewis acid sites on the alumina surface and in the electronic state of palladium. According to the results of infrared spectroscopic studies of adsorbed CO, the relatively large particles of Pd0 are the main form on the surface of nonmodified catalysts. The catalysts modified by the heteropoly compound contain single Pd+ and Pd2+ cations, and the fraction of Pd0 is substantially smaller. The specific features of the Lewis acidity of the catalyst surface determine the possibility of 1,3,5-trichlorobenzene adsorption and activation on the support and the spillover of hydrogen from Pd0. An increase in the catalyst stability as a result of support modification by the heteropoly compound can be explained by the appearance of new active sites in the interaction of palladium with the heteropoly compound or its thermal decomposition products.

We have examined the feasibility of preparing high-purity aluminum oxide by oxidizing granulated aluminum in a 0.1 M potassium hydroxide solution, followed by heat and acid treatments of the oxidation products. The aluminum oxidation product, consisting of two phases of Al(OH)3 (bayerite and gibbsite), was first heat-treated at temperatures of 300, 600, 900, and 1200°C; then treated with hydrochloric acid; and calcined at a temperature of 1450°C. It has been shown that raising the preheat treatment temperature increases the total concentration of impurities, including Fe impurities, but reduces the concentration of alkali metals (K, Na, and Li). Using 99.7%-pure aluminum, we have prepared aluminum oxide with a purity at a level of 99.886%. Using 99.98%-pure aluminum, we have obtained aluminum oxide with a purity at a level of 99.993%.

Processes accompanying the electrodynamic acceleration of a thin plate liner at a high accelerating current density are investigated. In addition to determining the electrical characteristics, shadow filming of the plate profile was carried out during the acceleration and the deformation of the profile in the region of fixed attachment to the current leads was monitored. A new experimentally reproducible effect in which the plate splits into three separate fragments, which is explained by nonuniform overheating by the current of the plate’s cross section and the electrodynamics of the process, was found. It was detected that, on the acceleration of copper liners, the current sheath is separated from the metal body of the liner and diverges in two directions. The nature of this phenomenon has not yet been determined.

For supercapacitors with sulfuric acid electrolyte, a promising carbon material was suggested, namely, activated carbon from waste wood. It was shown how the synthesis conditions of activated carbon affect its porous structure and electrochemical characteristics of supercapacitors on its basis. The changes in the porous material under different synthesis conditions were controlled using the highly informative limited evaporation method, which allows us to obtain complete information about the porous structure of the micro- and mesopores of the material within a relatively short period of time. The negative effect of the excess volume of macropores in the electrode on the capacity and energy based on the dry mass of electrodes was shown experimentally and analyzed. The properties of the synthesized material were compared with those of other carbon materials. The best samples of the developed material possess a specific electric capacity of over 390 F/g.

Two methods (spraying and calendering) for fabrication of supercapacitor electrodes are considered. Results of tests of double-layer capacitors with aqueous (sulfuric acid) and organic (tetraethylammonium tetrafluoroborate dissolved in acetonitrile) electrolytes and electrodes fabricated from activated carbon are presented. It is shown that, depending on the type of the electrolyte, it is necessary to use different methods for fabrication of carbon electrodes.

The process of advanced aluminum-alumina powders production for selective laser melting was studied. The economically effective method of obtaining aluminum&ndash, alumina powdery composites for further selective laser melting was comprehensively studied. The aluminum powders with 10&ndash, 20 wt. % alumina content were obtained by oxidation of aluminum in water. Aluminum oxidation was carried out at &le, 200 &deg, C. The oxidized powders were further dried at 120 &deg, C and calcined at 600 &deg, C. Four oxidation modes with different process temperatures (120&ndash, C) and pressures (0.15&ndash, 1.80 MPa) were investigated. Parameters of aluminum powders oxidation to obtain composites with 10.0, 14.5, 17.4, and 20.0 wt. % alumina have been determined. The alumina content, particle morphology, and particle size distribution for the obtained aluminum&ndash, alumina powdery composites were studied by XRD, SEM, laser diffraction, and volumetric methods. According to the obtained characteristics of aluminum&ndash, alumina powdery composites, they are suitable for the SLM process.

Simple, safe, scalable and low-cost method of hydrogen production via aluminum-water reaction was proposed. Hydrogen generation method is based on oxidation of coarse aluminum of centimetric scale in alkali aqueous solution with alkali concentration of no more than 0.1 M under intensive mixing of reaction medium. In presented work aluminum conversion (hydrogen yield) was studied depending on the aluminum to solution mass ratio (α changed from 30.1 to 2.7), the concentration of alkali in aqueous solution, the mixing rate, the form of aluminum particles (granules or chips) and chemical purity of aluminum. It was shown that under implemented experimental conditions alkali is continuously regenerated during oxidation reaction and synergistic effect of low content alkali aqueous solution and intensive mixing works. Aluminum conversion degree after 5 h oxidation of aluminum chips at 90 °C in 0.1 M KOH aqueous solution with α = 4 and mixing rate of 400 rpm was 75.4%. With alkali concentration increasing from 0.01 M to 0.3 M the conversion of aluminum increases from 20.7 to 95.7% (after 5 h at 90 °C, α = 4). Proposed method was strongly affected by mixing of reaction medium inside the reactor while it didn't feel the difference between aluminum chips and granules having specific surface area of 22 and 5.5 cm2/g respectively. Chemical purity of aluminum had little effect on aluminum conversion as well. Generally, proposed method can be used for hydrogen generation, aluminum waste utilization and special-grade alumina production.

We demonstrate the possibility of obtaining high-purity aluminum oxide by successive processes of hydrothermal oxidation of aluminum and vacuum heat treatment of the solid oxidation product (boehmite). The results of studies of changes in the structural properties and chemical purity of alumina samples obtained in the different modes of vacuum heat treatment of boehmite are presented. Experiments have shown the ability to produce alumina with a purity of 99.997% (the total content of all impurities is approximately 30 ppm) of aluminum with a purity of 99.8%. It was shown that the chemical purity of the final product depends on not only the temperature and time of heat treatment but also a number of other parameters of the process.

Simple and potentially energy efficient way for synthesis of Al/Al2O3 composites is described. Synthesis method is based on aluminum powder oxidation in water at 100-200 °C and following drying and calcination at 600 °C. Aluminum powder with average size of about 40 urn that is currently applied in additive manufacturing was used. Present work was devoted to the study of oxidation degree of aluminum and so the propagation depth and structure of Al2O3 shell in composite’s matrix. AI/Al2O3 composites were produced in different regimes with different maximum temperature and duration of the process of aluminium oxidation in water. Aluminum oxidation degree and aluminium content in obtained Al/Al2O3 were changed in the range from 5.5 % and 90.1 % to 21.3 % and 66.2 % respectively. The size of single crystals of Al2O3 in shell was changed from about 6 nm to 200 nm and the thickness of Al2O3 shell was changed from about 400 nm to 1000 nm by changing the regime for Al/Al2O3 composite production. Experimental results showed that Al2O3 shell was well clutched with aluminum core. Shell structure had cracks aroused by calcination process. Size distribution for obtained composites was very close for that of initial aluminum powder. All of these characteristics recommend the obtained Al/Al2O3 composites for additive manufacturing.

The present study is devoted to hydrogen generation at temperatures down to −40°C by aluminum and magnesium oxidation in various aqueous solutions. At −40°C the highest conversion degrees (180 min.) are 17% for aluminum powder in KOH aqueous solution and 43.4% for aluminum granules in HCl solution containing CuCl 2 . At −30 °C for MgCl 2 solution magnesium powder samples ball-milled with Ni, Ga and without additives yielded 82.8, 73 and 67.2% respectively.

This article considers modeling of the gas-filled neutron tube's ion source with discharge initiated by the non-recombined plasma from the previous pulse. The simulation was carried out with a homogeneous distribution of the non-recombined plasma with a concentration of 5.108 cm−3. In the case of filling the neutron tube volume by atomic hydrogen with pressure of 10-3 Torr, the slew rate of the extracted atomic hydrogen ion current equals only 10 mkA/mks. For increasing this value gas mixture of atomic hydrogen and xenon at a pressure of 0.5.10−3 Torr or molecular hydrogen at a pressure of 10−3 Torr to the atomic hydrogen were utilized. This led to increasing of the slew rate of the extracted atomic hydrogen ion current to 100 mkA/mks with xenon and 20 mkA/mks with molecular hydrogen.

Hydrogen forming by aluminium oxidation with liquid water of water solutions at low temperatures is complicated by the following reasons. Firstly, on an aluminium surface a film of oxide is formed effectively preventing further oxidation. Secondly, the rate of aluminium oxidation considerably decreases as the temperature of the system decreases. However, in this study the methods are given which enable one to overcome the above difficulties. The experiments on the oxidation of powdered activated aluminium in different water solutions have been carried out. The data obtained have been used to plot a number of curves characterizing hydrogen flow rates depending on the solution composition and the temperature of the process (the original weight of the powder was 0.25 g, solution volume - 300 ml, measuring time - 180 min). At −40 °C for KOH solution the yield of hydrogen was 50 ml, for CaCl 2 – about 5 ml, and for ZnCl 2 – approximately 2 ml. At −10 °C H 2 yield for NaOH was 264 ml, for KOH – 260 ml; at −20 °C: 100 ml for NaOH, and 225 ml for KOH. For KOH solution at temperatures of −30 °C and −40 °C the yields were equal to 192 and 49 ml respectively. Oxidation of granulated non-activated aluminium (2.5 g of aluminium per 300 ml of solution) with hydrochloric acid solution in the presence of CuCl 2 (2.5 g per 300 ml of solution) resulted in generation of more than 2000 ml of hydrogen during 300 min. For FeCl 3 solution the total value of hydrogen obtained during 180 min was equal to 70 ml, it also has been observed partial freezing of this solution.

Activated carbons produced from two wood species, birch and alder, were compared. For both carbons identical dependences of the porous structure and electrochemical parameters of the carbons on activation conditions were determined in a wide range of activation parameters (temperature, alkali/carbon mass ratio). In addition, an inverse dependence of the specific capacitance of the samples on the specific surface area was found.

Effect of the amount of F4 fluoroplastic binder in activated carbon electrodes on characteristics of double-layer supercapacitors with both aqueous and organic electrolytes was studied. It was shown that, depending on requirements to the strength of the electrodes, it is possible to raise by 20% the content of fluoroplastic without any significant decrease in the capacity of an electrode.

Three different types of current-collecting plates for air-hydrogen PEM fuel cell were manufactured and tested: unmodified titanium plates; gold-plated titanium plates and titanium plates treated by carbon ions implantation. It was shown that the applied surface modifications reduce contact resistance between titanium plate and carbon gas diffusion layer. Total ohmic resistance of fuel cell is reduced by 1.8 and 1.4 times in case of gold-plated titanium and carbon-implanted titanium, respectively, in comparison with uncoated titanium. Although gold plating turned out to be more profitable than carbon ion implantation in terms of electrical characteristics, in the last case, the performance enhancement was reached without using precious metals, which at mass production must play more important role. This technology promises to reduce the cost of bipolar plates manufacturing, while maintaining high electrical performance of PEM fuel cells.

The local surrounding of copper, antimony, and iodine atoms in multicomponent chalcogenide films CuI-PbI2-As2Se3 and CuI-SbI3-PbI2-As2Se3 deposited from solutions of chalcogenide glass in n-butylamine has been studied by the Mossbauer spectroscopy method on 121Sb and 129I isotopes. It was established that antimony atoms are in the Sb (III) state, where each antimony atom is surrounded by three selenium atoms. Copper atoms are in the Cu (I) state and are surrounded by iodine atoms. The local surrounding of copper, antimony, and iodine atoms in chemically deposited chalcogenide films is analogous to the local surrounding of atoms in the initial chalcogenide glass.

The goal of this work is to show the possibility of practical usage of the environmentally pure oxidation process of preliminarily dispersed aluminum (aluminum powders of the ASD or PAD grade according to TU (Technical Specifications) 48-5-226-87, which are serially produced in industry) with liquid water in order to obtain gaseous hydrogen in volumes sufficient to provide the operation of energizers based on airhydrogen fuel cells (AHFC) for portable and stationary devices (up to 3 kW). It is shown that the synthesis of aluminum oxides-hydroxides with the specified phase and chemical compositions as well as the particle shape and size can be provided simultaneously with producing commercial hydrogen.

The nanoporous structures of activated carbons and carbide derived carbons are investigated via the adsorption limited-evaporation method. Electrochemical properties of these structures used in the models of supercapacitors are analyzed. It has been found that porous structure parameters correlate with the specific characteristics of supercapacitors based on the mentioned materials.

An advanced method was investigated for production of ultrahigh-purity alumina α-Al2O3 (UHPA, 99.999%) with an oxidation of aluminum (purity 99.7%) granules in 0.1 g/mol aqueous solution of potassium hydroxide with a subsequent hydrochloric acid treatment and calcination of the oxidation product at 1450 °C. The evolution of impurities concentration after subsequent acid and thermal treatment was studied. The total concentration of impurities and especially iron impurity was decreased in UHPA while the concentration of alkali metals (K, Na, Li), on the contrary, was increased by the used production method (Al granules → reaction with alkali → acidic treatment + washing → thermal treatment). The proposed method allowed production of UHPA with purity 99.99% and 99.999% from pellets with the initial purity of aluminum 99.70% and 99.99% respectively. The advantage of the studied method of UHPA production is it's low cost and utility.

A model is considered that represents a chemical reactor for oxidizing aluminum in wet saturated steam to obtain a high-temperature and high-head flow of steam-hydrogen mixture, as well as aluminum oxides and (or) hydroxides. The thermal gas-dynamic parameters of the reactor are analyzed using a combined calculated and theoretical approach, which made it possible to determine the region of considered parameters optimal in terms of the thermodynamic efficiency of the reactor.

The superposition of nanosized pyrocarbon crystallites (NPCs; an NPC superposition is n sequentially formed pyrocarbon nanocrystallites each consisting of m monolayers) was studied. NPCs were obtained by the pyrolysis of methane and deposited on a porous surface of Trumem ultrafiltration membranes with D pore = 50 and 90 nm. A new uncoupled layer effect was found. After n-fold NPC superposition of an even number of monolayers (the total number throughout the superposition; i.e., m 1 + m 2 + ... + m n is even), further deposition of pyrocarbon nanocrystallites occurs in accordance with the previously determined kinetics of topochemical dehydrogenation of methane. However, if an NPC superposition is formed from an odd number of monolayers, the reaction rate constant decreases by more than one order of magnitude. A comparative analysis of the hydrogen adsorption ability of two carbon structures (NPC superposition and orientated carbon nanotubes of graphenes (OCNTGs)) showed that OCNTGs adsorbed up to ∼14% (relative to their mass) of hydrogen, whereas NPCs did not. It was shown for the first time that hydrogen adsorbed in OCNTG affected the transport properties of membranes, decreasing their performance with respect to liquids by a factor of 4–26.

Effect of the pH value on the molar solubility of solid hydroxides M(OH)3 and oxides M2O3 at 25°C and the constants of acid-base equilibria in aqueous media for crystalline hydroxides and oxides and dissolved hydroxides M(OH)3 (M = Sc, Y, La) were calculated using the thermodynamic method, with the formation of hydroxo complexes taken into account.

The activation of aluminum with low-melting gallium-based alloys makes it possible to obtain a material easily oxidizable by water at room temperature to release ~1.2 L of pure hydrogen per 1 g of metal. The kinetics and regularities of the interaction of activated aluminum with water were studied as a function of the amount and composition of metal activators, dispersity of the powder, and temperature. The phase composition of the solid reaction products was shown by X-ray diffraction analysis to depend on temperature and duration of the process.

An experimental examination of a thin diaphragm for integrated piezoresistive pressure sensors is reported. The diaphragm is fabricated by ultradeep anisotropic chemical etching of monocrystalline silicon. The mechanism of the process is investigated by exploring the morphology of the etched surface. Process-induced pyramidal hillocks, pits, and trenches are measured.

In this study a simple ecologically benign technology of high purity alumina production is presented. The synthesis process consists of three steps) oxidation of aluminum in water at temperature of 90 °C) calcinations of Al hydroxide in atmosphere at 1100 °C) high temperature vacuum processing of aluminum alpha oxide at 1750 °C. Oxidation of aluminum scrap was carried out under intensive mixing in water with small addition of KOH as a catalyst. It was shown that under implemented experimental conditions alkali was continuously regenerated during oxidation reaction and synergistic effect of low content alkali aqueous solution and intensive mixing worked. The product of oxidation of aluminum scrap is the powder of Al(OH)3. Then it can be preliminary granulated or directly subjected to thermal treatment deleting the impurities from the product (aluminum oxide). It was shown the possibility to produce the high-purity aluminum oxide of 5N grade (99.999 %). Aluminum oxide, synthesized by means of the proposed method, meets the requirements of industrial manufacturers of synthetic sapphire (aluminum oxide monocrystals). Obtained high pure aluminum oxide can be also used for the manufacture of implants, artificial joints, microscalpels, high-purity ceramics and other refractory shapes for manufacture of ultra-pure products.

A method for preparation of core-shell Al/Al2O3 composites with adjusted structure was proposed. It was based on two steps: fast hydrothermal partial oxidation of aluminum in continuous reactor and subsequent thermal treatment in muffle furnace to convert aluminum hydroxide to γ-Al2O3. It was shown the possibility to create metal-ceramic composites with adjustable content of metallic core by temperature of hydrothermal process. During experimental study it was established that oxidation degree for aluminum powder with average size of 22 μm was changed from 40 to almost 100 % when temperature in hydrothermal reactor changed from 280 to 350 °C. The reaction time was no more than 10 min. Obtained products were studied by scanning electron microscopy, pore structure analysis and XRD analysis. Prepared core-shell Al/γ-Al2O3 composites can be used as catalyst materials as well as for additive technologies.

Sr1-xCexFe0.8Co0.2O3-δ(x = 0, 0.05, 0.10, 0.15) ceramics were prepared by solid-state reactions, and their oxygen permeability was measured as a function of cerium content and membrane thickness at temperatures from 400 to 1000‡C and oxygen partial pressures from 102 to 105 Pa. The oxygen permeability of the ceramics was found to decrease systematically with increasing Ce content. The oxygen transport was shown to be limited by volume diffusion. Doping of the ceramics with 20 wt % Ag notably improves their cracking resistance during thermal cycling.

A method to synthesize graphene-like materials using dc high current divergent anode-channel plasma torch has been developed. Carbon atoms are generated by decomposition of propane-butane and methane in a thermal plasma jet. Products of synthesis are characterized by electron microscopy, thermogravimetry, Raman spectroscopy and porosimetry. Effect of experimental conditions on the morphology, phase composition and porosity of the products of synthesis are investigated. The optimal conditions have been found.

Water deoxygenation has been studied in a catalytic membrane reactor in which oxygen is reduced with hydrogen fed into the hollow fiber of a porous polypropylene membrane containing palladium metal on its outer surface. Palladized fibers obtained by different methods and the initial fibers have been characterized by dynamic desorption porosimetry, gas permeability measurements, X-ray structure determination, and light microscopy. The possibility of efficient water deoxygenation at room temperature is demonstrated. © Nauka/Interperiodica 2006.

Activated carbons with highly developed porous structure and nanosized pores (8 - 11 A) were prepared from alder wood using thermochemical activation method with sodium hydroxide. Properties of the obtained activated carbons were examined by benzene and nitrogen sorption, X-Ray diffraction and Raman spectroscopy. Tests of activated carbons as electrodes in supercapacitors were performed as well. It was found that specific surface area of above mentioned activated carbons was 1800 m 2 /g (Dubinin - Radushkevich). Raman spectroscopy demonstrated the presence of ordered and disordered structures of graphite origin. The performance of activated carbons as electrodes in supercapacitors have shown superior results in comparison with electrodes made with commercial carbon tissues.

Development of a new generation of gas-turbine engines calls for development of high-temperature alloys with better operating parameters than those of the current nickel superalIoys. The most important factor is an increase in the working temperature of the alloy and decrease in its density while retaining the level of its mechanical properties. These problems can be solved by using intermetallic compounds, in particular, nickel monoaluminide, as the base for new high-temperature alloys. Nickel monoaluminide NiAI ([3-phase) has an ordered bcc crystal lattice of the type CsCI (B2), a high melting point (1640~ and a low density (5.86 g / cm 3 ). The low plasticity of NiAI at low temperatures and a relatively low high-tempera:ure strength above 800~ restrict its use as a structural material. It is possible to increase the high-temperature strength of alloys based on NiA1 by alloying and / or developing special structures in the alloy: controlled crystallized structures or controlled recrystallized structures that provide a decrease in the fraction of the lateral boundaries. One of the methods of increasing high-temperature plasticity is grinding of the grains. However, fine-grained alloys have a decreased creep resistance. Therefore it is of interest to increase the low-temperature plasticity or increase the resistance to crack propagation by developing heterophase structures, in particular, heterophase alloys based on NiAI in which plastic, ductile laminas of "soft" phases with a disordered fcc crystal structure (e.g., a )'-solid solution based on Ni, ct ()')-solid solutions based on Fe) coexist with disperse segregations of more "rigid" strengthening phases, e.g., bcc crystal solid solutions based on refractory metals of group VIA Cr, Mo, W and / or refractory implantation phases such as carbides and borides [ 1 ]. Among the promising bases for developing alloys with the ductile component in the form of a )'-solid solution are (13 + "/)-alloys of the system N i AI C o , in which there is a wide two-phase region parallel to the side N i Co [2, 3]. In the system Ni AI Co fusible excess phases do not evolve and low-temperature transformations do not occur. It is also known that the value of the diffusion coefficient at 900~ de

This article uses laboratory simulation to compare the oxidation rates of oils operating in electrohydraulic servo loading systems, in which the oil is in contact with atmospheric oxygen and various steels and alloys (bronze, brass, aluminium) at approximately 150 C. The oxidizability and corrosivity of the oils were rated by the quantities of oxidation products (IR spectroscopy) and dissolved iron, chromium, nickel, titanium, copper, zinc and aluminium, which are components of the alloys (by atomic absorption spectroscopy). Finds that the proposed micromethod makes it possible to shorten by a factor of 8-10 the preliminary evaluation of an oil with respect to oxidation and corrosion. Suggests that the method can be used in selecting functional additive packages, since it gives a more objective rating of oil oxidizability than do the commonly accepted test methods.

1. An increase in hydrogen partial pressure in an N2−H2−CH4 gaseous mixture promotes an increase in the flow of carbon into the steel as a result of the increase in the diffusion mobility of methane in the Nernst layer. 2. The effective diffusion coefficient of carbon in unalloyed austenite in carburzing of steels in nitrogen-hydrogen mixtures with pure methane significantly exceeds the actual diffusion coefficient of it and increases with an increase in the partial pressures of hydrogen and methane. 3. In carburizing in an N2−H2−CH4 mixture there is observed the mutual influence of carbon and hydrogen on the kinetics of establishment of equilibrium with the steel with respect to hydrogen, which is probably caused by the existence of C−H complexes. 4. Carburizing in nitrogen-hydrogen mixtures with additions of pure methane may be intensified by increasing the partial pressures of methane and hydrogen and also by increasing the frequency of change as the result of the use of higher capacity centrifugal blowers.

1. The temperature dependence of the carburizing rate coeffcient in H2−CH4−H2O mixtures diluted with nitrogen is described by the Arrhenius equation K=K·e−Q/RT.