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It was experimentally shown that the reaction of the combustion of hydrogen-air mixtures in a detonation wave virtually completely (with an accuracy of 1%) occurs by a branched-chain mechanism; it is this mechanism that determines the characteristics of the detonation wave. [ABSTRACT FROM AUTHOR]

Changes in the phase composition of the 20 vol % TiSiC-Cu composite during detonation spraying as well as corresponding microstructure formation processes in the sprayed coatings have been studied. It was demonstrated that when the amount of the explosive acetylene+oxygen mixture is kept constant (under the constant filled volume fraction of the barrel of the detonation gun of a CCDS2000 facility), the phase composition of the coating depends on the composition of the explosive mixture. The TiSiC-Cu system is prone to interfacial interaction; therefore, in order to produce a dense coating preserving the phase composition, oxygen-depleted explosive mixtures should be used and small filled fractions of the barrel. As the temperature of the sprayed particles increases with increasing oxygen content in the explosive mixture, titanium silicon carbide reacts with copper, which results in the formation of the titanium carbide phase and dissolution of the de-intercalated silicon in the copper matrix leading to the formation of TiC-Cu〈Si〉 coatings. [ABSTRACT FROM AUTHOR]

Minor amounts of propane effectively inhibit the detonation of hydrogen-air mixtures at atmospheric pressure. Controlled variation of the amount of the admixture provides means to break up the steady-state detonation wave at a preset distance from the place of its origination and to regulate its velocity in a certain range. This is possible due to the branched chain character of the combustion reaction in the detonation mode. Propane is not inferior to propylene in the effectiveness of action on detonation and, owing to its low cost and higher availability, is preferable as a means of preventing the explosion and detonation of hydrogen-air mixtures. [ABSTRACT FROM AUTHOR]

The article presents a research study that analyzes the detonation of air and hydrogen mixture at atmospheric pressure. The study is undertaken through the use of an exhaust unit, mixers that will be used in the preparation of gas mixtures, and a data processing system. The results of the study show that propane is preferred than propene in terms of hydrogen explosion and detonation.

Minor admixtures of the simplest hydrocarbons can prevent detonation and break down a steady-state detonation wave in hydrogen-air mixtures at atmospheric and higher pressures. Therefore, the determining role in the appearance and propagation of the detonation wave is played by the branched mechanism and, accordingly, by the competing chain branching and termination reactions. Without taking into account these reactions, combustion theory cannot explain the basic regularities of the process, including the concentration limits of detonation. [ABSTRACT FROM AUTHOR]

The article presents a study on the role of a chain avalanche in a stationary detonation wave in hydrogen-air mixtures by examining the effect of inhibitors and the dependence of detonation characteristics on the inhibitor's molecular structure. It was found that inhibitors changed the detonation characteristics and terminated the reaction chains. It was concluded that chain branching and termination plays a significant role, which allows the inhibitors to affect the detonation characteristics.