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We present results of studies of inclusions in secondary sulfates (antlerite and a mixture of copiapite and coquimbite) and arsenates (erythrite and picropharmacolite) formed on the surface of technogenic bodies, such as stored waste from the enrichment of sulfide (Belovo and Ursk waste heaps) and arsenide (disposal maps of the Tuvakobalt plant) ores. A wide range of components were identified in the gas-liquid inclusions, the main ones being water and carbon dioxide. Hydrocarbons, oxygen-containing organic compounds, and nitrogen- and sulfur-containing gases were found in smaller but measurable amounts. Arsine H₃As was also detected in inclusions in picropharmacolite (calcium and magnesium arsenate-arsenite). The gas-liquid inclusions in secondary minerals reflect the composition of the interporous space in the waste body, filled with particular atmospheric gases entering the body in free form and with seasonal precipitation. The combination of in situ generated and penetrating gases determines the diversity of inorganic and biotic interactions in technogenic bodies. The presence of hydrocarbons and oxygen-containing organic compounds is, most likely, associated with bacterial transformations of organic matter (residual vegetation, wood, microalgae, and fungi). At the same time, carbon disulfide and sulfur dioxide are indicators of active inorganic reactions of decomposition of the sulfide matrix.

The main types of reservoir rocks have been identified within the Bazhenov-Abalak complex. To assess the geological resources of hydrocarbons, it is proposed to formally divide the entire set of lithological rock types comprising the Bazhenov-Abalak complex into two main varieties: fluid seals and reservoirs. We argue that it is possibile to distinguish between potentially productive and productive rocks, represented by siliceous and carbonate varieties, according to logging data. A possible mechanism for the formation of reservoir rocks within the Bazhenov-Abalak complex as a result of the tectonic-hydrothermal impact on these deposits has been reconstructed. An original methodology for identifying perspective zones of various categories of hydrocarbon accumulation in the Bazhenov-Abalak complex through integrating seismic data and tectonophysical modeling carried out on their basis has been proposed. For example, an assessment of the predicted geological resources of hydrocarbons contained in the Bazhenov-Abalak complex within the limits of 3D seismic exploration of the Yem-Yegovskaya area has been carried out. The necessity of assessing the prospects for oil content and calculating the predicted geological resources of hydrocarbons in the whole Bazhenov-Abalak complex, and not only in the Bazhenov Formation, is substantiated, based on a single mechanism of formation of reservoir rocks of tectonic-hydrothermal origin in them.

The article presents the results of pulse heating measurements for the thermal resistances of contacts of liquid lead with Al₂O₃ ceramics and steel in gaps, modeling a heat conducting liquid-metal sublayer in the developed fuel rods of fast reactors of a new generation. The method of obtaining and processing experimental data is described, the results of estimating the measurement error are presented, and the dependence of thermal resistances of liquid lead contacts in model gaps on temperature and number of melting and crystallization of lead is investigated. Based on the experimental results, the thermal resistance of a heat conducting liquid-metal sublayer in fuel rods is evaluated.

The experimental results on the structure of the two-phase “liquid metal-gas” medium in vertical channels depending on the gas flow rate and channel diameter are presented. Lead-bismuth melt at a temperature of 160°С was used as a liquid medium, and argon was used as a gas phase. Data were obtained on the shape of gas bubbles, temporary changes in the gas content in channels, histograms of gas content distribution, and features of the slug flow of gas in the metal melt.

The results of an analytical solution to the problem of heat distribution inside a massive solid sample with concentrated heat supply to this sample surface are presented. Analytical expressions for the non-stationary temperature distribution inside the body are obtained using the integral cosine Fourier transform and the Hankel transform. Examples of solution application for estimating the characteristic times of reaching the Chernov points Ac₁ and Ac₃ in model hypoeutectoid steels under the effect of laser radiation are presented. The application of this solution to calculating the cooling dynamics of ceramic Al₂O₃ and SiO₂ samples, affected by the air and water jets, is demonstrated.

The structure of a gas-liquid flow and interfacial mass transfer during the transition from the slug to the bubbly flow of ethanol-CO₂ mixture in a horizontal straight microchannel were experimentally studied. The experiments were performed for a channel with a rectangular cross section of 141×385 μm in the range of superficial gas and liquid velocities J_G = 0.16 - 0.8 m/s and J_L = 0.22 - 0.5 m/s. To determine a change in the volume of the elongated bubble along the microchannel length due to CO₂ absorption, the method of high-speed visualization with subsequent image processing was applied. The bubble frequency, velocity, size, and change in the volume of gas slugs and bubbles along the channel were measured, and volumetric coefficient of mass transfer from liquid k _L a was calculated. The measured volumetric mass transfer coefficient was compared with the known correlations and a new correlation was proposed for the transition from the slug to the bubbly flow due to interfacial mass transfer.

Numerical studies of aerodynamics and heat transfer in a vortex burner during flame oxygen combustion of pulverized coal are presented. The proposed numerical method has been tested using experimental data on oxygen combustion of coal in a flow. The influence of oxygen concentration in the blast on the processes of ignition and combustion of coal dust in a nitrogen-free environment has been considered. It has been established that for the burner under study, an increase in oxygen concentration from 40.1 to 66.7 vol. % leads to a change in the flow structure, an extension of the flame size, and an increase in the average value of unburned solid carbon concentration from 0.00136 to 0.4 g/m³ at a distance of 1.5 m from the burner.

The flow around a stationary gas Taylor bubble at downward flow velocities from 0.15 to 0.3 m/s in a vertical tube with a diameter of 20 mm was experimentally and numerically studied. Three-dimensional calculations were performed using the VOF (volume of fluid) method in the OpenFOAM package with application of the unsteady κ-ω SST turbulence model. Hydrodynamic characteristics of the flow were experimentally studied using the electrodiffusion method. The effect of flow velocity on the change in the shape of the gas Taylor bubble nose was shown. The calculated and experimental data were compared and their good agreement was shown. The distribution of velocities in liquid and gas was studied as well as the distribution of the liquid film thickness around a gas Taylor bubble. It is shown that the wall shear stress in the liquid film around a gas Taylor bubble does not depend on the downward flow velocity.

The results of thermodynamic calculations and experimental studies on hydrocarbon gas pyrolysis at atmospheric pressure in a combined plasma-chemical reactor with the production of hydrogen and carbon black with nano-carbon structures are presented. The plasma pyrolysis technology consists of heating hydrocarbon gas in an electric arc combined reactor to a temperature that ensures its dissociation into hydrogen and carbon black in a single techno-logical process.

Gas-driven atomization is the major approach for production of metal powders. This method gives up to 70 % of the entire metal powder production. However, modern trends demonstrate new requirements to the particle size distribution. This drives the development of novel methods for power production. Here we present the plasma-jet atomization method.