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Globalization arises the problems among nations and confessions and they become more acute, which requires strong focus of the state and society. Untimely responses to these problems and negative societal attitudes towards migrants tend to develop into nationalistic ones, which can lead to serious consequences. Due to this fact, it is particularly important to analyze the situation in concern of tolerance in society towards migrants, especially among young people. The article considers the results of the research conducted among university students in order to highlight a tolerant attitude to migrants. The author used the research results of the American Institute of Public Opinion Gallup in order to make comparative analysis. The average level of tolerance among students was determined, and it was significantly lower than the global Migrant Acceptance Index. This indicates the poor situation and relevance of the relations with migrants. The author proposes the measures aimed at shaping tolerant consciousness in society, creating friendly atmosphere on the part of the local population to migrants, to people of different nationalities, who in their turn should accept the values of the other society and obey the national laws.

Within the framework of the classical one-dimensional theory of detonation based on conservation laws, the lower branch of the adiabat of energy release of the combustible mixture as a geometric place of the points of the final state of the system admits a solution; for combustion waves whose propagation velocity is D_fl, this solution stays in the range from zero to the deflagration velocity: 0 ≤ D_fl ≤ D_def . The normal combustion wave propagation velocity S_u is located in this interval (0 ≤ S_u ≤ D_def), but it is traditionally calculated with the use of the thermal theory of combustion rather than detonation theory. Various approaches to choosing the final state point on the lower branch of the energy release adiabat for the normal flame are analyzed in the present paper. An analysis is performed and estimates are provided both for the degree of correspondence of the predicted and experimental velocities of flame propagation and for the degree of correspondence of the qualitative behavior of these dependences on the basis parameters of the mixture. For most hydrocarbon fuels considered in the study, the best agreement with the experimental data on S_u is provided by the formula defining the flame velocity D_fl as the mean geometric value between the diffusion velocity S_diff and deflagration velocity D_def .

A two-stage reduced model of chemical kinetics of detonation combustion of a mixture of two fuels, i.e., hydrogen and carbon oxide (syngas), with an oxidizer is proposed. Based on this model, a two-dimensional numerical calculation of the parameters of an irregular cellular structure of the detonation wave in the considered binary mixture of two fuels with an oxidizer is performed.

Initiating explosive charges in a cylindrical tube with one end face being plugged, vortex rings with diameters of the order of 1 m and initial velocity of motion greater than 100 m/s are obtained. Such rings emit a clearly heard acoustic signal, which is of interest for studying generation of acoustic waves by vortices and scaling mechanisms of noise generation. Vortex rings are generated due to exhaustion of a high-velocity gas jet formed after shock wave propagation over the tube. The measured vortex velocities are found to be weakly dependent on the explosive mass, i.e., as the mass increases, the fraction of energy transformed to the vortex ring energy becomes smaller.

This paper presents a physicomathematical model and the results of numerical solution of the spark ignition problem of a suspension of a bidisperse aluminum powder in air. The critical ignition conditions of the aluminum powder suspension in air are determined numerically as a function of on the particle size and mass concentration and the content of large and small particles in the suspension. The study has shown the effect of the fine fraction of particles in the bidisperse aluminum powder on the critical spark ignition conditions of the aluminum powder suspension in air with the subsequent establishment of a steady regime of combustion front propagation.

The differential thermal analysis is applied to study the influence of activated charcoal with multilayer graphenes (three and more layers) on the thermal decomposition of a substance based on hydroxyl ammonium nitrate and carboxyl methyl cellulose. It is demonstrated that addition of activated charcoal with multilayer graphenes lead to an increase in the burning rate of hydroxyl ammonium nitrate up to four times. Addition of activated charcoal at the stage of thermal decomposition leads to a decrease in temperature and time of the chemical reaction until complete decomposition of ammonium nitrate.

Comparative results of experiments aimed at studying the evolution of dust-laden jets induced by the presence of structural elements and grooves on the surface of loaded specimens are reported. The results are obtained with the use of pulsed X-ray radiography and synchrotron radiation. Information on dust density changes in synchrotron diagnostics is obtained by using multiframe filming. In the case of single-frame recording by means of pulsed X-ray radiography, a glancing detonation wave was used for studying the dust behavior instead of the normal wave.

An analytical model of the equation of state is developed based on theoretical ideas about the structure of TATB. The model is validated against experimental data obtained in static and dynamic experiments. The theoretically sound equation of state was used to match different experimental data in order to maximize the use of empirical information. It is expected that the application of the obtained equation of state will increase the accuracy of description thermodynamic parameters of unreacted TATB in numerical simulations of shock-wave and detonation processes.

The detonation pressure of an emulsion explosive sensitized by polymer microballoons was determined for normal and oblique incidence of a detonation wave on the target. The initial density of the explosive ranged from 0.2 to 1.2 g/cm³. The obtained pressure values are in good agreement with the calculated values known from the literature and are compared with the detonation pressure values of an emulsion explosive sensitized by glass microballoons. The reaction time and isentropic exponent of the emulsion explosive used were calculated.