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The paper analyzes the contemporary ecological situation in Russia, characterized as steadily negative. It presents a forecast of the environmental load for the period 2016-2020 obtained using the dynamic input-output model with an ecological module. We consider two Russian economic development scenarios: one was designed at the Institute of Economic Forecasting, RAS, the other at the Institute of Economics and Industrial Engineering, SB RAS. According to the forecast for both scenarios, the environmental load will further increase. We estimate the necessary size of ecological taxes for negative impacts on the environment and provide a rationale for some ways of improving the government environmental policy.

The article deals with the development of transregional interaction between the Republic of Belarus and the Russian Federation. Basing on the analysis of Russian andBelarusian regions' experience, we reveal the main problems of such a cooperation. It is shown that, within the context of the Union State, the major obstacle to making contacts between regions and creating transregional connections in economy, culture, science, and education is the complications resulting from of the countries' federative and unitary structures. We discover that current contacts are geographically diversified. We give our recommendations for the development of foundations for cooperation in innovative sectors of the economy.

The article analyzes modern problems of local government, their dynamics, and guidelines for their solution. Based on annual surveys conducted among heads of municipalities in Russia, we reveal trends implying a changing role of local government in the economic crisis. The existing regulatory framework is shown as imperfect as it is limiting the opportunities of local government. We also discuss the results of the latest stage of municipal reform. By analyzing the change trends for organizational forms of local government, we discover a reorientation from direct elections of heads of municipalities to competitive job substitution procedures. We study the benefits and drawbacks to various models of local government organization envisioned by the newest stage of municipal construction. The article demonstrates divergences between legislatively established and the most expedient (from the standpoint of heads of municipalities) models. The conclusion is that there is a need to monitor the effectiveness of the changes to the legislation and consider the opinions of heads of municipalities when designing a research-based development concept for the system of local government.

The Rayleigh-Benard convection in a chemically active gas in the chemical equilibrium state is numerically studied in the Boussinesq approximation. A flat layer with isothermal horizontal boundaries free from shear stresses is considered. Thermodynamic parameters of the gas (hydrogen-oxygen mixture) are calculated by the previously proposed model of chemical equilibrium. It is shown that the allowance for recombination and dissociation processes leads to the emergence of an additional factor at the Rayleigh number. An expression for the growth rate of infinitesimal perturbations and a relation for the critical Rayleigh number as a function of temperature are derived. It is found that the neutral curves consist of the upper (instability due to heating from below) and lower (instability due to heating from above) branches. Results calculated for a nonlinear steady mode are reported.

The interaction between natural convection and the heat explosion in porous media is studied. The model consists of a nonlinear heat equation coupled with the Darcy equation for the motion of an incompressible fluid in a porous medium. Numerical simulations are performed using the alternate direction finite difference method and the fast Fourier transform method. A complex behavior of solutions is observed, including periodic and aperiodic oscillations and an oscillating heat explosion. It is shown that convection can decrease the risk of the explosion due to additional mixing and heat loss, but it can also facilitate the explosion due to temperature oscillations arising as a result of instability of stationary convective regimes.

The characteristics of soot particles formed during combustion of liquid hydrocarbons in a laboratory version of an original burner with injection of a superheated steam jet into the combustion region are experimentally studied. The concentration and particle size of soot formed in the burner plume are measured by a diffusion aerosol spectrometer. It is shown that the majority of the primary particles have sizes ranging from 20 to 60 nm. The particle concentration in the external flame rapidly decreases with distance from the burner exit from 10⁸ to 5x10⁶ cm^-3. The images obtained by transmission electron microscopy demonstrate a chain-branching (fractal-like) structure of aggregates. The primary particles composing these aggregates have a bulbous structure with the interplane distance between the layers smaller than 1 nm. Compact aggregates with sizes up to 500 nm are observed in cooled combustion products. The content of soot in combustion products is 35 mg/m³, and the mean particle mass is 7x10^-12 mg. Results measured in the combustion modes with injection of a superheated steam jet and with injection of an air jet are compared.

Issues of explosion and fire safety of silane during its transportation and storage are intimately related to its possible catastrophic leak off from tanks if they become cracked. It turned out that silane self-ignition is possible at some leak off velocities. The interest of the aerospace industry to problems of ignition and combustion of silane combined with other fuels should be also noted. Experimental investigations of such problems, which are rather expensive and labor-consuming, provide primary information for the development and verification of mathematical models of physical and chemical processes, capable of predicting the characteristics of silane mixing, ignition, and combustion induced by its exhaustion. Recent experiments of Prof. Chen and his colleagues from Taiwan allowed them to determine the critical length of the silane jet (distance from the tube exit where ignition of exhausting silane occurred) and the time of silane ignition. In the present work, an attempt is made to simulate these phenomena within the framework of the concept of the critical concentration of silane with studying the dynamics of silane leak off from a tube.

This paper presents experimental dependences of the temperature, thermo-emf, speed and width of the combustion wave of a heterogeneous mixture of 5Ti + 3Si on the pressure of quasi-isostatic compression. Combustion parameters are calculated from measurements of the temperature gradient and the difference between the electrical potentials in the combustion wave. It is shown that under quasi-isostatic compression conditions, the maximum burning rate is 90 mm/s and the width of the combustion wave is 10 mm. It is found that the voltage-temperature characteristic of combustion of a heterogeneous mixture of 5Ti + 3Si has a hysteresis shape. The cause of the hysteresis related to a change in the bulk concentration of electric charge carriers in the combustion wave is discussed.

This work demonstrates that the heating of fracture fragments of rods made of VT1-0 commercial titanium and its alloys OT4-1 and PT3V in gaseous oxygen at a pressure p _O2, which is accepted in this paper and in the works of other researchers as critical pressure p *, only leads to melting of individual regions of the formed juvenile surface, which differ from each other only by obstructed heat sink, and the metalì-oxygen interaction does not transfer into combustion. However, this interaction does transfer into combustion during which the bulk of the metal burns out at a slightly higher pressure p **, which can be calculated from the thermal explosion equation for temperature T * that is equal to the melting point of titanium, with account for the dissociative absorption of oxygen molecules on the melt surface and the heat exchange coefficient corresponding to the case where the heat is transferred from the melt hemisphere to the semibounded solid body.

The ignition mechanism and the dependence of the composition of the products of combustion or thermal explosion in a mixture of 2Zr + Al + C on the initiation temperature and heat transfer conditions were studied. Heat transfer conditions were changed by varying the size of the samples and the gaseous medium in which the experiments were performed. Two contusion regimes were found: a low-temperature regime in which zirconium aluminides formed and carbon and part of the zirconium remained unreacted and a high-temperature regime in which the reaction products were carbide and zirconium aluminide. Upon re-initiation, the low-temperature combustion products reacted in the high-temperature combustion mode. The observed dependences are due to parallel reactions in the three-component system.