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The causative agent of acute rheumatism has not been found. The peculiar reaction of the macroorganism with allergic biases, noted during the process, suggests that, even when the pathogen is found, the macroorganism will attract no less attention. Therefore, attempts to use means that enhance the protective forces of him have their raison d'etre, although their (means) action would be hypothetical.

During the combustion of high-energy condensed systems, the formation of an intermediate structure - a skeleton layer, is possible, which has a significant effect on the combustion process. An experimental study was carried out to determine the nature of the effect of the curing of the binder on forming this structure. The article shows the specific role of the used hardener, polyethylene polyamine, presents the solutions for simulating the phenomena in the surface layer in the presence and absence of a skeleton layer, as well as shows the possibility of predicting the characteristics of the combustion process.

The article is devoted to a simulation of evolution of high-temperature chemical reacting multiphase combustion products flow with condensed phase particles of different sizes. The gas phase is a mixture of different oxidizing, neutral and fuel components. The particles include two main fractions – smoke oxide particles and agglomerates. The agglomerates have a complex structure. They consist of metal, oxide and gas inclusions. The agglomerates evolution process includes several chemical-physical phenomena, which affect properties of the agglomerates and the whole multiphase flow. The evolution of smoke oxide particles is associated with changes of concentration and size of the particles. The article contains results of a parametric study of the model. Factors affecting properties of the condensed phase in the combustion products flow are described.

A mathematical model of the evolution of multiphase combustion products flow for propulsion systems has been developed. It is based on the physical picture of the process formulated on the basis of the available experimental data. In accordance with this picture, agglomerates are the main source of evolution. A variety of physicochemical transformations of these particles and their relationship with gas phase and smoke oxide particles (SOP) properties are considered. The analysis of the phenomena that have the most significant effect on slag-formation has been carried out. It is shown that vapor-phase burning of agglomerate metal is one of the most significant phenomenon in this regard. It has been determined that properties of SOP most significantly affect two-phase losses of specific impulse. It is established that size of the SOP particles in the process of evolution increases significantly. The results of the study allow suggest that the evolution process has a significant impact on motor performance.

The model of evolution of the condensed products as a part of a flow of combustion products of solid propellant is developed. The model includes the description of physical and chemical transformations for two basic fractions of the condensed products: agglomerates and smoke oxide particles (SOPs). Model testing is carried out using experimental data about evolution of the condensed products for two compositions in the conditions of a one-dimensional flow. These compositions differ considerably in properties of combustion products at a surface of burning propellant. The results of testing give the grounds to draw a conclusion about high enough quality of modeling.

Actual tasks of ladle desulphurization of hot metal are discussed. Main advantages and disadvantages of existing technologies of hot metal desulphurization are analyzed. Most perspective technologies of hot metal desulfurization for Ukrainian steelmaking plants are determined., Розглянуто актуальні питання позапічної десульфурації рідкого чавуну. У ній проаналізовано основні переваги та недоліки існуючих технологій видалення сірки з чавуну. Визначені найбільш перспективні технології позапічної десульфурації чавуну для вітчизняних підприємств.

The present work is devoted development of model of agglomerating process for propellants based on ammonium perchlorate (AP), ammonium dinitramide (ADN), HMX, inactive binder, and nanoaluminum. Generalization of experimental data, development of physical picture of agglomerationfor listed propellants, development and analysis of mathematicalmodelsarecarriedout. Synthesisofmodelsofvariousphenomena taking place at agglomeration implementation allows predicting of size and quantity, chemical composition, structure of forming agglomerates and its fraction in set of condensed combustion products. It became possible in many respects due to development of new model of agglomerating particle evolution on the surface of burning propellant. Obtained results correspond to available experimental data. It is supposedthatanalogicalmethodbasedonanalysisofmathematicalmodels of particular phenomena and their synthesis will allow implementing of the agglomerating process modeling for other types of metalized solid propellants.