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Combustion of solid propellant charges in rocket propulsion systems usually occurs under conditions of intense flow of combustion products (solid rocket motor), gaseous oxidizer (hybrid rocket motor) or air (ramjets and air-breathers).This causes the so-called erosive burning effects, resulting in a change in the burning law under the influence of the gas flow. The main approaches to modeling the erosive burning of solid fuels in high-velocity gas flow are considered. Methods for the criterial description of the results of experimental studies of the erosive burning of solid fuels under transonic and supersonic flow conditions are analyzed.

Stability of diffusion combustion of fuel jets impacting on targets and interaction of two jets (pure propane-butane and the same fuel with addition of carbon dioxide) are experimentally studied. Data on combustion failure are obtained for various variants of jet interaction, as well as information about the composition of combustion products, air-to-fuel ratio, and completeness of combustion before combustion failure. It is shown that the domain of stable combustion of impacting and opposing jets is expanded by more than an order of magnitude as compared to combustion of individual free jets.

This paper presents the results of two large-scale tests performed to clarify the conditions for the detonation of propane-air compositions in model surface clouds in the absence and in the presence of confining rigid walls. Model clouds with sizes of 15 x 6 x 4.2 and 15 x 6 x 2 m were confined by plastic tents. A mixture of starting reactants in the cloud was ignited by the hot detonation products propagating along a perforated 0.82 x 23 m tube passing through the space of the tent. Hot detonation products were injected from the tube through holes of 20 and 40 mm diameters. Detonation of the propane-air mixture in the tube was initiated by explosion of an explosive charge placed at the tube end. Detonation occurred in the propane-air cloud bounded on one side by a rigid vertical wall, and no detonation was observed in the cloud with similar injection of hot products without a rigid wall. It is concluded that the divergence or convergence of the flows of hot detonation products play a key role in the process, being responsible for the presence or absence of detonation in the mixing region, respectively.

The activity of plates of CuO/Al2O3/FeAlO/FeAl ceramic metal structured catalysts is compared by varying the alumina content in them. The catalysts were prepared by impregnation of the ceramic metal carriers obtained by mechanochemical activation of powder mixtures of an alumina precursor (20-50% (wt.)), iron and aluminum, followed by hydrothermal treatment and calcination. It is shown that with increasing content of the alumina precursor (product of thermal activation of hydrargillite) increases the specific surface area of the carrier and meso- and macropore volume and reduces its mechanical strength. The content of the active component (CuO) also increases, resulting in an increase in the specific activity of the catalyst despite a reduction in the effectiveness of using the active component. The activity of catalysts with a medium concentration of alumina is sufficient to initiate oxidation of methane.

On the basis of physical concepts and the results of thermal theory of combustion, the qualitative analysis and mathematical simulation of transformation of steady temperature distributions along the length of the adiabatic reactor. It is revealed that, with a certain amplitude and a frequency of harmonic perturbations of the velocity of reagents, it is possible to increase the thermal stability of the process (obtain the pre-explosion heating).

Results of an experimental study of ignition of a water-coal fuel in a high-temperature air flow are presented. The fuel is obtained on the basis of the mark D coal or filtrational cake of the Severnaya dressing plant. Based on the experimental results, physical and mathematical models of the processes of thermal preparation and ignition of water-coal fuel particles are formulated, which take into account the joint proceeding of the most relevant physical and chemical transformations (which exert an essential effect on the ignition condition) and the processes of heat and mass transfer during the induction period. A comparison of the basic ignition characteristics (ignition delay time and limiting values of the gas medium temperature), which are obtained experimentally and theoretically (based on results of numerical simulations), leads to a conclusion that the water film affects the dynamics of the ignition process.

The elemental structure of green leaves of Siberian sea buckthorn (Hippophae rhamnoides L. ssp. mongolica Rousi) growing under endemic conditions of the West Siberia was studied. The simultaneous quantitative content of K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rd, Sr, Y, Zr, Nb, Mo, Pb in green leaves and soil, as well as coefficients of biological absorption of these elements were determined by the method of RFA-SR (X-ray fluorescence analysis using synchrotron radiation). Species-specific absorption features of elements by leaves of sea buckthorn were revealed, what was expressed in the increased accumulation of vitally necessary chrome and elements with unidentified biological role: niobium, scandium, titan, zirconium and strontium, relatively to the terrestrial phytomass. It was shown that leaves of Siberian sea buckthorn could serve a food source of vitally necessary chromium and manganese in the form of the easily digestible biogenic form. It was established that fruits of sea buckthorn do not concentrate toxic chemical elements: lead and arsenic.

An effect of ultrasonic treatment exerted on the structure and mechanical properties of polyacrylamide, polyhexene, polyethylene and oil paraffin solutions was investigated. Schemes are proposed for the destruction of polyhexene and polyethylene via a radical mechanism. It has been found that the acoustic impact on the oil paraffin solution in decane does not affect the nature of the molecular mass distribution for n-alkanes, but results in increasing the temperature of phase transitions and changing the shape of crystallites.

The effect of ozonation on the change of the componental composition of coal-tar crude benzene was studied. It was established that ozonation facilitated the decrease of the amount of unsaturated sulphur compounds and a relative increase in the share of benzene.

Processing method of fluorine-containing wastes of the aluminium industry aimed at the preparation of hydrogen fluoride was considered. Thermodynamic parameters of the sulphatisation process of fluorine-containing wastes were calculated. The necessity of the stage of the preliminary oxidative roasting of wastes for the removal of the carbon constituent that hinders the interaction of sulphuric acid with fluorine-containing particles was established. Kinetic characteristics and optimal conditions of the sulphatisation process of fluorine-containing wastes in the static mode were determined.