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Conductive heat losses from the base of a lean methane--air inverted flame stabilized behind the trailing edge of a thin rod have been experimentally evaluated. The results favor the view that the heat losses to the flame holder play a crucial role in the inverted flame stabilization and blow-off. Simple estimations have been performed, which indicate that the well-established correlation between the mixture composition and the boundary velocity gradient at the flame holder, usually considered as a proof of the flame stretch theory of blow-off, can be explained without involving the flame stretch concept. The suggested explanation of this correlation is based on the assumption that the heat loss to the flame holder is the main factor that determines the inverted flame blow-off behavior and on the similarity between the mechanisms of energy and momentum diffusion in gases (Pr ≈ 1).

A possibility of using some kinetic models for the description of detonation of a gaseous hydrogen-air mixture is justified. A hierarchy of mathematical models from the simplest model of combustion under static conditions to the model of unsteady nonequilibrium gas dynamics is numerically constructed. Verification is performed on the basis of experimental data on the ignition delay time as a function of temperature and on the detonation wave velocity as a function of dilution of the mixture by argon or nitrogen. A mathematical technology for the description of cellular detonation propagation in channels of various engineering devices is developed on the basis of detailed and reduced kinetic mechanisms of nonequilibrium chemical transformations within the framework of the ANSYS Fluent commercial software system. It is demonstrated that the cell size in a mixture diluted by argon by 92% in a channel 30 mm wide is in good agreement with experimental data.

Thermokinetic data on the oxidation of ASD-4 powder modified by impregnation with V₂O₅ gel were obtained by thermogravimetry and differential scanning calorimetry under heating in air to 1250 °C at a rate of 10 deg/min. The phase formation process directly during oxidation of the modified ASD-4 was studied by powder x-ray diffraction method using a synchrotron radiation source. A mechanism for the effect of V₂O₅ on the oxidation of ASD-4 is proposed on the basis of literature data and analysis of the results of the studies performed.

The effect of preliminary mechanical activation of low-calorific-value powdered formulations in a planetary ball mill on the main parameters of the subsequent thermal explosion has been studied. It has been found that in mechanically activated compositions, the initiation temperature of thermal explosion is reduced by hundreds of degrees. The maximum decrease (1300 °C) is observed for the Ti + 4 wt.% C system. Regimes of preliminary mechanical activation of reaction mixtures and the subsequent thermal explosion conditions producing Ti₃Al and Ni₃Al single-phase intermetallic compounds with nanometer grain size were determined. For the 3Ni + Al composition, the energy accumulated during mechanical activation was evaluated. It is shown that the initiation temperature of thermal explosion in the MA compositions studied can be used to estimate the temperature that develops in the mill drums.

The article presents argumentation in favor of transition to high bench stripping in open pit mines in Kuzbass, which will increase coal production and improve mine performance. The authors find functional connection between the duration of the transition to high bench stripping and the increase in the finite depth of an open pit mine. Substantiation is given to choosing the height of a bench based on the change in relationship of operating costs and a cut layer height. The practical significant of the research is development of a new approach to validating expediency of high benches for mining with truck&shovel and creation of a procedure to find increment in ultimate pit contour in transition to stripping with high benches.

Advanced technologies and modern high-production machines for underground mining of thick gently dipping coal demand strict adherence to technological discipline, reduction in operational loss and selection of optimized ventilation modes. The authors analyze ventilation schemes used in working areas in thick gently dipping seams in order to reveal influence exerted by the schemes, methods and parameters of ventilation on distribution of air loss in mined-out areas.

The article reports research findings in the area of open pit coal mining and substantiates alternative technologies based on new technological and organizational principles of open pit mining. Using the method of geometrical analysis of an open pit mine field and technological design of mining systems, stage-wise mining technologies have been developed for the case when mining front advance is changed. Such technologies ensure the improvement of a wide range of technical-and-economical and ecological performance of an open pit mine. The main flow charts of the mining sequences are interconnected with natural-technological groups of deposits, that influence cross-wise configuration of an open pit (ultimate contour) and structural characteristics (parameters) of working areas and generate geometrical type of an open pit field.

Under discussion is the equipment for open pit mining of limited coal reserves. Methods of overburden dumping are systematized. A new dumping method is offered; it allows reducing land withdrawal by means of utilizing adjacent open pit. The author presents relations for area of internal dumping, considering coefficient of dumping in the adjacent open pit and the volume of the adjacent open pit. The feasibility of overburden placement in mined-out pits is analyzed.

In focus is fuel briquetting using coal mining and processing waste. The authors present an integrated technology of coal and coke dust processing, including oil agglomeration of input components and fuel briquetting using binder. The optimal binder is chosen to be heavy coal-tar. Influence of a type of compaction and content of different binders on strength of fuel briquettes is analyzed. The quality characteristics of concentrate obtained from dressed coal and coke dust and fuel briquettes made of the concentrate are presented.

The authors review methods to assess reliability of forecasting of peak vibration velocities under large-scale production blasting using statistical analysis of regression residuals. The regression analysis of experimental data and the subsequent statistical analysis of the regression residuals is exemplified.