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The state of the art in the field of initiation of combustible mixtures is overviewed. Recommendations on using various formulas for estimating the critical energy (of both ignition of the mixture and initiation of detonation) are given. The importance of the spatial and temporal components in the energy release law is noted, especially for initiation optimization. Unsolved and new problems of the theory of combustion and detonation are formulated.

The current status of experimental research of continuous detonation of fuel-air mixtures in flow-type annular combustors is described. Experimental data for C₂H₂—air, H₂—air, and CO/H₂—air mixtures are analyzed, systematized, and generalized. Basic specific features of continuous spin detonation and the influence of geometric parameters of flow-type combustors are described. The effect of physical and chemical parameters on the domain of continuous detonation formation is analyzed. It is concluded that the fundamental knowledge of continuous detonation processes in hydrogen and hydrocarbon fuels gained up to now allows one to consider the possibility of using them in air-breathing detonation engines.

Three-dimensional detonation in channels of different cross sections and spinning detonation in channels of circular cross sections are numerically studied. A possibility of galloping detonation in a supersonic flow of a mixture with a variable fuel concentration over a plane channel width is discussed. Conditions of detonation formation under the action of moving boundaries of the flow region due to rotation of an elliptical cylinder and in a variable-size square chamber are obtained. Formation of three-dimensional detonation in a supersonic flow in a helical channel of elliptical cross section and in a variable-size square channel is calculated.

Analytical solutions of the problem of collapsing of a spherical shell or cavity in an ideal compressible liquid having a constant density during its motion are constructed. The influence of the gas located in the cavity on the motion of the cavity boundary is studied. A quantitative characteristic of energy cumulation is proposed. An expression for energy cumulation in the case of shell or cavity collapsing is derived. The energy cumulation obtained in this study is compared with Zababakhin's results.

This paper presents an analytical review of modern quasihomogeneous and discrete models of gasless combustion. Particular attention is given to experiments that make it possible to distinguish between homogeneous and microheterogeneous regimes of this process. It is shown that in the cases where different theoretical models predict different behavior of the combustion wave at the macroscopic or microscopic level, experiments provide data in support of discrete models. The development of these models allows for a fresh look at the problem of controlling the propagation parameters of gasless combustion waves and the development of reaction compositions with specified strictly reproducible characteristics.

This paper presents a review of studies of the characteristics of condensed explosives in the reaction zone of which the distribution of parameters does not correspond to the classical detonation theory. An increase in the pressure and particle velocity behind a shock in liquid explosives and the possiblity of the existence of a stationary detonation wave without a Von Neumann spike in pressed explosives are interpreted withi the framework of models that take into account the possibility of chemical reactions directly at the shock wave front. It is noted that in the absence of the Von Neumann spike, both Chapman-Jouguet detonation or an underdriven detonation regime can occur.

A phase-plane method is proposed to model flow fields bounded by constant-velocity detonation waves propagating in TNT charges. Similarity transformations are used to formulate the problem in the phase plane of non-dimensional sound speed Z versus non-dimensional velocity F . The formulation results in two coupled ordinary differential equations that are solved simultaneously. The solution corresponds to an integral curve Z(F) in the phase plane, starting at the Chapman-Jouguet (CJ) point and terminating at the singularity A, which is the sonic point within the wave. The system is closed by computing thermodynamic variables along the expansion isentrope passing through the CJ point, forming, in effect, the complete equation of state of the thermodynamic system. The CJ condition and isentropic states are computed by the Cheetah thermodynamic code. Solutions are developed for planar, cylindrical, and spherical detonations. Species profiles are also computed; carbon graphite is found to be the predominant component (≈10 mol/kg). The similarity solution is used to initialize a 1D gas-dynamic simulation that predicts the initial expansion of the detonation products and the formation of a blast wave in air. Such simulations provide an insight into the thermodynamic states and species concentrations that create the initial optical emissions from TNT fireballs.

This paper generalizes the experimental data of the authors on the production and properties of thin-layer nanostructured explosives obtained by thermal vacuum sublimation. The method involves sublimation of explosive under heating in high vacuum, followed by deposition (condensation) of the explosive vapor on the substrate. Under these conditions, it has been shown that nanostructured polycrystalline layers of explosives containing a large number of micro-defects (pores and dislocations) are formed. In the explosive transformation in the deposited explosive layer, nano- and submicron-sized defects of the structure act as hot spots. The result is a significant reduction in the critical detonation dimensions. The nanostructured explosives studied by the authors are able to detonate at a layer thickness of 20–100 μm. Furthermore, their detonation velocity is substantially less dependent on the layer thickness than that of charges of the same explosives made by traditional technologies. Nanostructured explosives can also be used as components of explosive compositions with improved detonability.

In the article, the possibilities of plein air practice for the development of creative activities of the future art teachers are considered. In this context, there is emphasizes the task of forming a picturesque idea of the future image that includes the emotional image assessment, painting and expressive possibilities of specific painting materials, as well as the direction of the painting actions. The main objective of plein air practice consists in deepening and consolidation of theoretical and practical knowledge of the art disciplines received in the course of training. It is necessary to teach students to transfer in the works the integrity of landscape motives, taking into account the general tone and color condition of illumination, to compare colors of nature with respect to the color tone, lightness and saturation, to maintain the tone and color scale. An effective condition of painting training in the plein air is the organization of the process of vocational training on the basis of the principles of activity approach to training, in which such qualities of the personality are realized as independence and creative activity necessary for the artist-teacher for successful work. Special tasks on the change of color accents in composition with several color spots orient students towards the development of original system of interaction of spots in the color space of landscape motive, which activates the creative activity of the future artist-teacher. The technique of training of landscape painting needs to be based on understanding of creative activity as a fundamental incentive of mastering the landscape art. The pedagogical orientations should be aimed at the formation of an initial picturesque plan which realization has to include the entire process: from the search for a composition, through the etude work in the plein air and up to a final solution in the material.

The article is devoted to the analysis of specificity of ethnosocial and ethnocultural processes in the Altay Republic. Using the achievements of the Novosibirsk ethnosociological school, the authors apply the concept of «interethnic community» as a key concept, emphasizing its subjective (the subject of self-organization, formed as a result of stable interethnic cooperation at a local level, such as the municipal and regional level) and objective (the object of state administration which seeks to regulate interethnic relations) components. This methodological position allows us considering the region under study as a systemic integrity in view of its multi-ethnicity, multi-religious character and multi-culturalism. In the article, the economic, social, political and cultural characteristics of the region are given; the areas of inter-ethnic tensions are designated. In particular, since the Kosh-Agach district is a specific area of interethnic tensions, this causes increased interest of the authors to the analysis of ethnosocial processes in this area. On the basis of empirical sociological research conducted in the Altai Republic in the period of 2013–2014 years, the authors examine the characteristics of ethnosocial processes and interethnic relations in the region. The ethnosocial and ethnocultural specifics of the region is reflected in the analysis of the opinions of the respondents and experts community from the region about government; about the attitudes to the influx of migrant workers and specificity of their interaction with the local habitants of the republic, about specificity of internal migration in the Altai Republic; about tourism business in the region and consequences of its impact on the local population, about tourism-related changes in the economic behavior of the inhabitants of the Altai, the relations of Altai people with the tourists; in addition, the respondents' opinions about the problems of indigenous peoples living in the territory of the Republic are analyzed, and in particular, the views about the problems of preservation of cultures of indigenous peoples and the crisis of Altai culture in general.