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The paper deals with the problem of ascertaining the value of air flow velocity necessary to prevent electric current through the motion of ionized air between two asymmetrical electrodes. By means of this experiment, the authors aim to prove the ion basis for the phenomenon of a mechanical force generated by a system of asymmetrical electrodes connected to high voltage. Particle image velocimetry (PIV) is used to precisely map the vector field of the air flow around the electrodes. The calculated and measured values of air flow velocity are compared, and good agreement between them is found.

A Couette flow of liquid, described by a modified Vinogradov-Pokrovsky model with a non-monotonic flow curve is simulated. It is shown that the analytical solution of the stationary problem has an infinite set of solutions. The time-dependent problem is numerically simulated in the assumption that the components of the structural tensor take values corresponding to a current change in the velocity field. It is determined that the time it takes for the plate velocity to reach a given value significantly affects the velocity profile and the dependence of tangential stresses on an operating shear rate. It is shown that, as this time decreases, the shear banding of the flow is observed not only for shear rates corresponding to the downward branch of the flow curve, but also in the entire domain of its ambiguity.

The purpose of this study is to prepare specimens of 10 and 20% nano Al₂O₃ particle reinforced LM25 metal matrix composites (MMCs) by stir casting. Another goal is to develop models using the response surface methodology (RSM) approach for predicting the surface roughness parameters and cutting force components during machining of the MMCs by a CBN7020 tool. With the help of the model developed, comparisons of 10 and 20 wt. % nano Al₂O₃ particle reinforced LM25 MMCs are performed. Combined effects of three cutting parameters (cutting speed, feed rate, and depth of cut) on the surface roughness parameters and cutting force components are explored by using the analysis of variance (ANOVA). The resultant values of the parameters are found to agree well with available experimental values.

The main regularities of the degradation of the strength properties of structural materials (metals and alloys) resulting in a decrease in long-term strength were investigated. A mathematical model describing the viscoplastic deformation and damage accumulation in polycrystalline structural alloys in creep was developed using the equations of the mechanics of damaged media. The paper presents the results of experimental studies of the short-term creep of 12Kh18N9 steel and VZh-159 high-temperature alloy at constant temperatures and different stresses set in the samples and the results of experimental studies of creep recovery in some structural steels. The deformation and damage accumulation were studied numerically and the results were compared with the data of field experiments.

Four brittle materials are subjected to shock tests: gabbrodiabase, two modifications of cast iron, melted quartz, and beryllium. An interferometer is used to locally probe a free surface in order to calculate its velocity, thereby determining the criterion of the initial stage of brittle fracture of all materials tested - the formation of horizontal steps at the forefront of a compression pulse, which indicate the presence of local sources of fracture of the material. It is determined that the brittle material resists the shock compression as long as it has the reversible transfer of momentum and energy of the processes occurring at meso- and macrolevels.

Based on the elastic theory and the seepage flow theory, a new analytical solution with consideration of the seepage force is proposed to determine the external stress on the lining of a circular TBM tunnel. According to this solution, the relationships between the permeability coefficient of rock masses and the maximum allowable drainage flow are studied. The influence of the controlled drainage flow and the elastic modulus of surrounding rocks on the external stress is discussed. Moreover, in order to validate the results obtained from the elastic analytical solution developed in this paper, a comparison between the results obtained from the solution considering the seepage force and that without consideration of the seepage force is performed.

Based on the analysis of peculiarities of Siberia’s colonization during the period prior to 1917, the article discusses the issue on “colonial” status of Siberia, as well as economic and political- administrative factors which gave the birth to the colonial syndrome in its development. Historical analysis allows assertion that the notion “colony” when used in relation to Siberia isn’t quite relevant to the existing, habitual and established, meanings of this term. On the one hand, colonial syndrome should be seen as the inevitable development stage in the “life cycle” of newly developing territory, on the other hand, it had been conditioned by the deeper reasons of political nature concerned with the so called “minimalist” approach to managing the Siberian development. In significant part, these problems were the logical consequence of the structural weaknesses of the Russian economy in itself.

The article analyzes the views of N. M. Yadrintsev, who was of the largest researchers of Siberia and a representative of regionalism, his assessment of conditions and results of the Siberia development and peopling, colonization policy towards the region in historical retrospect and as compared to the European expansion in other regions of the world, his arguments in favor of voluntary colonization as opposed to other colonization models, his seeing of the most urgent problems of developing Siberia, such as Siberian indigenous peoples issues, use of natural resources, Siberian industry development, a sad state of education and culture, dominated state of trade monopolies in the region, and regional governance. The paper shows that N. M. Yadrintsev’s ideas became widespread in the intellectual environment and partly received support by government circles. While many problems have been solved, however, a vision of the region as a raw material colony, an object of external control, and some other aspects still remain challenging.

The article examines some different definitions of the Arctic supporting zone in the national legislative instruments and names zones’ main features. They are: general and social functions - to develop communication and resource potential, to improve quality of life; organizational setting - “project of projects” on the “special territory”; economic model - government-private partnership; spatial structure - transport and industrial framework, consisting of mail lines, hubs and various centers; type - the level of natural resource development, the maturity of specialization, the center and periphery ratio, the specifics of financial mechanisms. The authors have made the first comparative-rating analysis of those zones. The Methodology includes choice of a municipality as an operating unit, calculation of zones’ indicators summation of municipal indicators, use of the Municipal Passports data, rating calculation for each indicator and average overall. The rating allowed determining the factors of strong zone differentiation, which affect the socio-economic development of the Arctic regions. The region’s proposals for the projects in zones are considered. The authors find important to analyze of the mechanisms for the implementation of anchor and other investment projects.

The article discusses the historical and sociological aspects of the transformation of the image of Siberia in the public consciousness of Russians in the XIX - XXI centuries. Based on the analysis of the texts of historians and philosophers of the past, as well as modern researchers, the reasons for the ambivalent perception of the region are shown. It is concluded that the integration of Siberia into the sociocultural space of Russia is the result of the latter’s self-colonization. Modern exotisation of Siberia allows us to conclude that this process has not yet been fully completed.