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Dear authors, colleagues and readers of the magazine! Before you the third issue of the journal "Vocational education in the modern world." The structure of the journal still includes three sections: philosophy, pedagogy, psychology. In contrast to the previously presented materials to the scientific and pedagogical communities, the general line of this issue is "through" consideration of problems related to the continuity of the vertical to university and university education proper. This is not accidental, since the conference that represents the conference in November (November 23-24) is devoted to the most acute, in the opinion of the editorial staff of the journal, a set of issues related to the state, technologies and risks of managing educational processes in the modern educational space of Russia. The problem of the unity of the educational space is closely intertwined with questions of continuity. This is clearly evidenced by the materials coming to the discussion site. Increasing the competitiveness of Russian education, which was the subject of the first discussion platform, is impossible without the creation of a single educational space based on the principles of continuity and optimality of management. It is these principles with professionalization that will be the focus of the 3rd and 4th issues of the magazine and the upcoming conference. Dear authors, colleagues and readers! We invite you to express your point of view on the state and prospects for the development of educational management in the Russian educational space in the pages of our magazine. Regards.

Moscow held Moscow international educational fair - 2017 on 12-15^th April,, 2017. This fair was organized by the Ministry of Education and Science of the Russian Federation, under the UNESCO patronage. The paper highlights the main materials of the special project «Career guidance» which was organized for pupils by career guidance companies and institutions, psychological centers and consulting organizations. The project focuses on interraction between education system and labor market. It is the guidebook on education and career possibilitieas, which gives an opportunity to ask mportant questions in the area of education and labor markets, to realize different possibilities and ways, to understand how modern professions are being developed and what skills should the pupils have for being successful in the labor market.

Interest in the combustion chemistry of multi-fuel mixtures is related to the need to study the combustion of natural gas, which is known to be a mixture of alkanes. It has been found by molecular beam mass spectrometry studies and numerical simulation that the width of the zones of consumption of hydrogen and methane in the H₂/CH₄/C₃H₈/O₂/Ar flame and the width of the zones of consumption of methane and propane in the CH₄/C₃H₈/C₄H₁₀/O₂/Ar flame differ significantly from each other. The causes of this phenomenon were determined by analyzing the simulation results. It has been found that in the presence of heavier compounds, lighter fuels, such as H₂ and CH₄, are formed which reduces the rate of their consumption and, hence expands the zone of their consumption in the flame. The influence of the presence of hydrogen in the fuel mixture on the concentration of C₂ hydrocarbons has also been studied. It has been established that the addition of hydrogen reduces the maximum concentration of ethane, ethylene, and acetylene in the flame, while the fraction of unsaturated C₂ hydrocarbons with respect to saturated ones also decreases.

An oxygen-diluted partially premixed/oxygen-enriched supplemental combustion (ODPP/OESC) counterflow flame is studied in this paper. Flame images are obtained through experiments and numerical simulations with the GRI-Mech 3.0 chemistry. The oxygen dilution effects are revealed by comparing the flame structures and emissions with those of a premixed flame and partially premixed flame (PPF) at the same equivalence ratio ( f _= 0.95 and f _f = 1.4). The results show that both PPF and ODPP/OESC flames have distinct double flame structures; however, the location of the premixed combustion zone and the distance between premixed/nonpremixed combustion zone are significantly different for these two cases. For the ODPP/OESC flame, the temperature in the premixed combustion zone is lower and the premixed zone itself is located farther downstream from the fuel nozzle, which leads to reduction of NO and CO emissions, as compared to those of the PPF. Therefore, by adjusting the distribution of the oxygen concentration in the premixed and nonpremixed combustion zones, the ODPP/OESC can effectively balance the chemical reaction rate in the entire combustion zone and, consequently, reduce emissions.

This paper describes the numerical modeling of gas flow in a plane vortex chamber by using the Navier-Stokes equations. The model is based on the laws of conservation of mass, momentum, and energy for nonstationary two-dimensional compressible gas flow in the case of axial symmetry with a tangential component of the gas velocity. The processes of viscosity, thermal conductivity, and turbulence are accounted for. It is shown that the transition of the kinetic energy of gas into thermal energy as a result of the transfer processes leads to the formation of hot spots in the boundary layers near the walls of the chamber. The gas temperature at these hot spots can exceed the gas ignition temperature, while the gas remains rather cold in the neighboring regions. This could be the reason for the cold gas self-ignition observed in the experiments. The turbulence of the flow and the processes of mixing and diffusion of the components make a significant contribution to the capacity of gas self-ignition.

A high-speed camera system is used to observe the diffusion flame of a Bunsen burner in linear motion. The resultant sequence of instantaneous motion pictures of the flame accelerating at 3.60 m/s² is processed and used to study the change in the flame area and specific floor area of the flame over different temperature ranges. The results indicate that the total flame area increases in the fuel control zone as the velocity increases over the range of experimental speeds employed (< 0.90 m/s); then the total area quickly decreases in the transition region and is stable in the cross-flow wind control zone. As the velocity of the fire source increases, the low-temperature and specific floor areas adopt more dominant positions in the low-speed fuel control zone. In the high-speed cross-flow wind control zone, the area of the high-temperature zone and specific floor area take the dominant positions. The transformation between the two situations occurs in the transition zone. The cross-flow wind increases the high-temperature specific floor area of the fire compared to that of a stationary fire; the consumption in the moving fire also becomes correspondingly more concentrated and fierce.

The effect of preliminary injection (pre-injection) of a gas (heated air, methane, or ethylene) ahead of the entrance of a three-dimensional inlet in a supersonic flow with Mach numbers M_¥ = 2-4, stagnation temperature T * = 300 K, and flow rates of the injected gas corresponding to 0-6% of the flow rate of air through the inlet is numerically studied. The gas is injected through orifices located behind the end faces of pylons mounted upstream of the inlet entrance. The computations are performed by the ESI-FASTRAN software package, which allows one to calculate three-dimensional viscous turbulent gas flows by a time-dependent method with the use of the Reynolds-averaged Navier-Stokes equations. Experimental investigations of pre-injection are performed with the use of small-scale and large-scale inlet models at M_¥ = 3-4 and 6. A positive effect of pre-injection on stable (without stalling) deceleration of the incident flow in the case of mass supply and on initiation of ignition and stable combustion in the combustion chamber is confirmed.

A new criterion for thermal explosion in exothermic reacting systems for the case of arbitrary one-step conversions. The method of calculation is based on the analysis of the equation of maximum temperatures obtained for closed systems with the consumption of reagents taken into account. The dependence of the maximum temperature on the Semenov and Todes parameters is bistable and the critical conditions are determined by the extremum conditions on the relevant parametric diagrams. The demarcation lines of ignition in the Todes criterion-Semenova criterion parametric plane are calculated for second-order exothermic reactions. Comparison of numerical and analytical calculations showed that they are in satisfactory agreement

The mathematical model of thermal explosion and synthesis of products in a mechanically activated 3Ni + Al mixture is simulated in a macroscopic approximation. It is shown that activation of original components significantly increases the formation rate of a Ni₃Al intermetallide. The experimental data are used to determine the thermophysical and kinetic constants of the process.

A model for the gasification of solid propellants containing a two-phase medium in an intermediate stage. The formation of the gas phase proceeds in two ways: chemical reactions result in gas products, which, in turn, initiate the formation of bubbles, in which vapor forms from the liquid phase of the fuel. Gas products play an important role only at the earliest stage of bubble development; the minimum size of gas-phase nuclei is determined from their minimum pressure. The he bubble volume grows primarily by evaporation of the liquid phase. A kinetic equation for the bubble concentration and the necessary boundary conditions are formulated. Arguments are given to suggest that a maximum temperature cannot be formed in the gasification zone and that natural turbulence can be generated by collapsing bubbles. The sound produced by burning solid rocket propellants is explained by the collapse of a huge number of microscopic bubbles. If the processes in the two-phase zone are neglected, the formulated system of equations goes over into the Belyaev-Zel'dovich model equations.