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The Bachat earthquake ( M = 6.1) with the epicenter coordinates of 54.29° N, 86.17° E occurred on June, 18 2013 near the Bachatsky coal strip mine, is the world’s largest earthquake induced while mining solid minerals. More than 5000 aftershocks were registered and the spatial volumetric structure of the aftershock area was investigated. The Bachat coal field is located in the Salair zone of the Kuznetsk Depression and is represented by a brachysynclinal fold of a very complex structure characterized by the damage and fracturing behaviors of rocks. The main event is confined to the coal-mine pit wall, with the greatest density of aftershocks observed in its middle portion. In the cross section, aftershocks form a wide area with its deepened portion shifted towards the Kuznetsk Depression, while large faults bounding the depression dip down under the Salair Ridge. In the exposed pit wall, at a depth of 4 km, the activated area resembles a rhombus whose horizontal diagonal line runs across the entire length of the mine pit and decreases both in upward and downward directions. The area is seismically activated to a depth of 6 km, with more intense activation of rock mass observed within the 1-3 km depth interval. Results of the study of the mechanisms of aftershock sources revealed a disagreement between the stress state of rock mass of the Bachatsky open-pit coal mine modeled from the mechanisms of aftershocks, and the mainshock mechanism of the Bachat earthquake.

The digital elevation model (SRTM03) of the central part of the Lower Amur province is analyzed. The Limuri-Amgun ring structure is identified on the basis of a set of features, and it is also the location of the Pilda-Limuri and Kherpuchin-V’yunsky gold-ore regions, as well as the Albazino deposit, known for large industrial gold deposits and many small deposits and ore occurrences. The distribution of linear and ring elements of the relief is analyzed and geologically interpreted, and its spatial relationship with gold deposits and ore occurrences is shown. The relationship between the morphological severity of the ring structure and the deep structure of the region is shown. It is revealed that the structure is magmatic and characterized by a high concentration of intrusive bodies. According to the reference data on the age and composition of the igneous complexes of the region, the formation of the ring structure is associated with the processes of neoformation and transformation of the Earth’s crust and upper mantle during the end of the Late Cretaceous and the beginning of the Paleocene in a suprasubduction geodynamic setting.

The physical processes of crystallization of melt droplets in water have been studied using the droplet granulation and melt centrifugation methods. A mathematical model has been developed that makes it possible to determine the cooling and crystallization rates and dendritic structural parameter of aluminum alloy granules from the initial data of the process, the diameter of melt droplets, and cooling conditions. Predicting the dendritic parameter of the microstructure of granules allows one to predict the level of microstructure dispersion and hence the strength properties of the granulate material. The model parameters take into account the speed of droplet motion, features of heat removal processes, and the temperature dependence of the thermophysical parameters of the media. An application program implementing the developed mathematical model has been developed. Implementation of the developed mathematical model has been carried out using the Microsoft Visual C++ programming language. The mathematical model has been tested in the granulation of highly alloyed aluminum alloys (D1 and D16 alloys of the Al-Cu-Mg system, and B95 and B96Ts alloys of the Al-Zn-Mg-Cu system) obtained by centrifugal melt spraying and the droplet methods with cooling in water. Crystallization rate in full-scale samples has been measured based on an analysis of the dendritic structural parameter of the material. Analysis of the calculated values of the dendritic parameter and its measurements for real granule samples has shown that there is good agreement between the simulation and measurement results.

The deposition of a nickel-based cermet coating containing 60 % tungsten carbide has been studied. The effect of substrate preheating up to 500 °С on the intensity of the in-situ synthesis of secondary ceramic particles obtained by dissolving the initial particles in a metallic matrix has been investigated. It has been shown that preheating contributes to the prevention of cracks and pores in the coating. Using synchrotron radiation, it has been found that additional heating of the sample during surfacing to a temperature of 500 °С does not cause significant changes in the phase composition of the resulting composite.

The influence of substrate preheating on the structure of a cermet-coating obtained by direct metal deposition from Ti64 alloy reinforced with B₄C particles. Coatings containing 15 %. B₄C were obtained for the first time. It has been shown that the use of substrate preheating makes it possible to produce cermet coatings without cracks. It has been found that in tribological tests, that the scratch volume of the cermet coating decreases by a factor of eight compared to the coating with the content of B₄C 10 %.

Results on a nanoparticle collision with a target calculated by the molecular dynamics method are presented. The first problem being solved is a nanoparticle collision with a target under the conditions of cold gas-dynamic spraying. The second problem deals with nanoparticle extension, which adheres to the target due to the collision. It is shown that a chemical bond between the nanoparticle and target due to the collision. The bond in the case of titanium nanoparticle impingement onto an aluminum target is found to be stronger than that in the case of aluminum nanoparticle impingement onto a titanium target. The reason is that the titanium nanoparticle penetrates into the aluminum target to a greater depth.

The centrally symmetric problem of determining the velocity field in a continuous elastoplastic medium under a camouflage explosion has been solved using the assumptions of the unoscillatory nature of the motion and the incompressibility of the medium in the regions of plasticity and elasticity. The solution was found using a camouflage equation-the relation for determining the pressure on the contact surface of an expanding explosion cavity. The solution allows one to estimate the dimensions of the expansion and plastic deformation regions and the impact of explosive disturbances on objects

A nitrogen jet expanding during its exhaustion from a nozzle into a vacuum chamber is numerically simulated by a hybrid approach. The flow parameters in the nozzle and in the near field of the jet are determined by solving the Navier-Stokes equations by using the ANSYS Fluent software. The gas flow at large distances from the nozzle exit is modeled by the Direct Simulation Monte Carlo method by using the SMILE software system. Such an approach makes it possible to perform sufficiently accurate simulations in the near field of the jet; moreover, the temperature nonequilibrium of the expanding gas jet and other effects of rarefaction in the far field of the jet are taken into account. The approach is verified by using various approximate analytical models of gas exhaustion into vacuum. A comparison of the numerical results with available experimental data shows that they are in good agreement.

The flow in a far plane momentumless turbulent wake is described using a mathematical model obtained from the algebraic Rodi model of Reynolds stresses. The model is similar to the two-parameter ( k ̶ ε ) turbulence model in the far-wake approximation with a modified empirical constant in the diffusion terms of the equations. A group-theoretical analysis of the mathematical model of the wake was carried out and and a self-similar reduction of the equations of models to a system of ordinary differential equations was performed. An approximate solution of the corresponding boundary value problem is constructed using an asymptotic expansion of the solution in the neighborhood of the singular point.

A passive method for reducing the drag of cylinder by installing a flat plate behind it at a Reynolds number Re=10⁵ has been studied. The paper presents the results of an ANSYS Fluent simulation of the flow around the cylinder-plate system, including the velocity and pressure fields, streamlines, and the dependences of the drag coefficient and the position of the separation point on the surface of the cylinder on the relative length of the plate. It has been found that the drag coefficient of the cylinder-plate system can be reduced by approximately 40% compared to the case of an isolated cylinder.