Effect of the properties of the water sorbent on the heat generation in the Fe-C-NaCl-H<Subscript>2</Subscript>O-O<Subscript>2</Subscript> system

The water adsorption and retention behaviors of vermiculite, silica gel, activated carbon, and a zeolite are analyzed in relation to their pore structures, and their effects on the dynamics of heat generation in Fe-C-NaCl-H₂O-O₂-water sorbent systems are investigated.     

Criteria for assessing technological properties of gabbro-basalt rocks

Various forms of the acidity coefficients and mineral compositions of gabbro-basalt raw materials from ten Russian deposits are calculated. These data are used to assess the physicochemical and technological properties of the rocks required for mineral fiber production and stone casting. Examples of the regulation of the mineral formation process during the melting and crystallization stages are presented.     

Thin-layer nanocrystalline composite coatings: Production,structure, and properties

To obtain a nanocrystalline structural state of materials based on aluminum and titanium, high degrees of deformation are employed: rolling with considerable reduction; and shear under high pressure (5 GPa). The nanocrystalline materials obtained are used to create thin-layer composites, with nanocrystalline silicon between the uniform layers. Measurements show that the microhardness of the composites after the application of high pressure is 2.5 (for Al–Si) and 6 (for Ti–Si) times that of the initial material, while optimal practical properties are retained. The nanocrystalline composites obtained may be recommended for ultrahard thin-layer coatings on narrow or stressed local sections of components and for local corrosion protection.     

Chemical composition and distribution of the components of valley peat from Amur oblast

The chemical composition of sedge peat from the Egor’evskoe deposit as lowland peat from Amur oblast was characterized. The elemental composition of organic matter and mineral macro- and microcomponents was studied, and the distribution of bitumens, their fractions, and humic acids in the depth of occurrence was revealed. It was found that peat genesis processes occur over the entire vertical profile, and the most converted organic matter is formed at a depth of to 90 cm. The individual composition of alkane fractions consists of C₁₃–C₃₆ normal structure homologues with a carbon preference index somewhat higher than unity; the presence of pristane, phytane, and farnezane was detected. In the fractions of fatty acids, predominantly even compounds from C₁₀ to C₃₀ were identified with special distribution features at the separate stages of peat formation. The analysis of the individual composition of n-alkanes and fatty acids made it possible to supplement botanical characteristics with information on the contribution of macrophytes, algal material, and microorganisms to the formation of the organic matter of peat.     

Recovery of valuable components from basalt waste by sintering it with sodium carbonate

The sintering of basalt waste with sodium carbonate at 1000–1200°C followed by leaching of the sinter with water, a NaOH solution, or hydrochloric acid is reported. The most effective leaching agent is hydrochloric acid, with which all of the valuable components of basalt pass into solution and silicon can be selectively separated as silicic acid.     

94-K Superconducting Yttrium Barium Cuprate Films Prepared by Spray Pyrolysis of Methacrylate Solutions

High-T _c YBa₂Cu₃O₇ films 2–6 m in thickness were deposited onto lanthanum aluminate substrates by spray pyrolysis of methacrylate solutions, and their properties were studied. By optimizing the deposition conditions (substrate material, solution concentration, and firing schedule), single-phase, nearly stoichiometric films well adherent to the substrate were obtained, with T _c = 94 K and T = 9 K.     

Intensifying dehydration in decanter screw centrifuges

Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 11, pp. 3–5, November, 1989.     

Magnetic properties and time-temperature stability of properties of on iron-and cobalt-based amorphous and nanocrystalline alloys with a destabilized domain structure

Magnetic properties of amorphous and nanocrystalline alloys with a saturation magnetostriction close to zero and a destabilized magnetic domain structure have been studied. A change in the magnetic characteristics has been investigated after two treatments leading to a destabilization of the domain structure: magnetic annealing in a high-frequency magnetic field of 80 kHz and quenching in water. It has been shown that the destabilization by both the first and the second methods markedly improves magnetic properties of amorphous alloys. Nevertheless, upon quenching of amorphous alloys a time-temperature instability of the magnetic properties has been observed. The quenching in water of the nanocrystalline alloys under study results in a deterioration of the magnetic properties.     

Preparation, deformation, and failure of functional Al-Sn and Al-Sn-Pb nanocrystalline alloys

Changes in the structure, hardness, mechanical properties, and friction coefficient of Al-30% Sn, Al-15% Sn-25% Pb, and Al-5% Sn-35% Pb (wt %) alloys subjected to severe plastic deformation by equal-channel angular pressing (with a force of 40 tonne) and by shear at a pressure of 5 GPa have been studied. The transition into the nanocrystalline state was shown to occur at different degrees of plastic deformation. The hardness exhibits nonmonotonic variations, namely, first it increases and subsequently decreases. The friction coefficient of the Al-30% Sn, Al-15% Sn-25% Pb, and Al-5% Sn-35% Pb alloys quenched from the melt was found to be 0.33; the friction coefficients of these alloys in the submicrocrystalline state (after equal-channel angular pressing) equal 0.24, 0.32, and 0.35, respectively. The effect of disintegration into nano-sized powders was found to occur in the Al-15% Sn-25% Pb, and Al-5% Sn-35% Pb alloys after severe plastic deformation to ? = 6.4 and subsequent short-time holding.