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The analysis of the engineering process of reforming dead catalysts for the extraction of platinum group metals has been carried out. Fully-dead catalyst, having passed several cycles of regeneration and entitled to utilization, has the considerable carbonaceous deposits, both on external and internal surfaces. Their content averages 5.0% of the mass of the catalyst. The research objectively consisted in selection of the sweet roasting modes, promoting the fullest removal of the dense carbonaceous deposits from the surface of the dead platinum-rhenium catalysts. The kinetics research of carbonaceous removal deposits from the surface of the catalyst was carried out in a pipe-still heater; oxygen content, duration and temperature of sweet roasting being varied. The maximum temperature during the research reached 950°C, the maximum duration of isothermal holding didn't exceed 6 hours. The extent of carbonaceous deposits removal was calculated by changing sample weight. The kinetic curves were approximated by high-order polynomials, which made it possible to obtain a diagram, illustrating the degree of organic deposits removal, depending on temperature and firing time. It is shown that in the environment enriched to 30-35 vol. % oxygen, the engineering process of catalysts for regeneration is possible to be carried out at 650 °C, with holding for 2 hours at a specified temperature. The alternative of sweet roasting is the air blowing of dead catalysts at temperature of 800 °C within an hour. Both modes guarantee the complete removal of the dense carbonaceous deposits from the surface of the dead catalyst.

A total of 1410 patients with ischemic stroke (IS) of four main clinical and pathogenic subtypes, viz., atherothrombotic, cardioembolic, hemodynamic, and lacunar strokes, were studied. We analyzed the dependence of the pathogenic subtype of the stroke, its background pathologies, and stroke risk factors on the age and gender of the patients. It was found that senior patients were more susceptible to atherothrombotic ischemic strokes and patients of working age more frequently suffered from lacunar and hemodynamic strokes, although cases of atherothrombotic strokes in this age cohort were more often observed in male patients. The significance of arterial hypertension in the development of ischemic stroke decreases with age but the role of cerebral arteriosclerosis, coronary artery disease, and cardiac arrhythmias greatly expands. At retirement age, the prevalent risk factors of ischemic stroke are lack of physical exercise, being overweight, and dyslipidemia, with reducing roles of smoking and stress, which are more relevant to the working ages. The occurrence of particular risk factors and IS background diseases is age specific but in different age periods and for different pathogenic subtypes of ischemic stroke this dependence changes, while at the retirement ages it is less distinct than for the working-age cohort.

Abstract: The promoting effect of potassium included in Cr/MgO catalysts for the synthesis of nitriles from acetonitrile and methanol was found. The 5% Cr-0.5% K/MgO catalyst exhibited the highest activity in the synthesis of nitriles.

In this article we present the method of creation of spare parts warehouse, conditions for ensuring the best reliability of warehouse with lowest total cost of spare parts storage. The method is based on Poisson-law distribution of probability of consumption of each part in a given period of time. The calculation program was developed for use on a personal computer.

The results of testing motor and transmission oils for thermal-oxidative stability, including optical density and coefficient of thermal-oxidative stability, are presented. According to the results of the study, the temperature range of application of the oils was determined. The method of testing engine and transmission oils with cyclic temperature changes is presented, which allows comparing oils of the same purpose by the number of cycles of raising and lowering the test temperature, as well as identifying them for compliance with the classification according to performance properties groups.

The paper considers the problem of accumulation and disposal of oil sludge including a resistant water-oil emulsion, oil sludge classification and treatment methods are presented. Detailed studies have revealed that stability giving to the emulsion system consisting of two immiscible liquids requires presence of the third component which performs function of a stabilizer. These stabilizers create boundary adsorption films which are a structural and mechanical barrier to contact and coalescence dispersed water globules. The structure of intermediate layer and lower sublayer is considered, the reasons for their formation are determined.

The paper considers the problem of accumulation and disposal of oil sludge including a resistant water-oil emulsion, oil sludge classification and treatment methods are presented. Detailed studies have revealed that stability giving to the emulsion system consisting of two immiscible liquids requires presence of the third component which performs function of a stabilizer. These stabilizers create boundary adsorption films which are a structural and mechanical barrier to contact and coalescence dispersed water globules. The structure of intermediate layer and lower sublayer is considered, the reasons for their formation are determined.

The results of testing motor and transmission oils for thermal-oxidative stability, including optical density and coefficient of thermal-oxidative stability, are presented. According to the results of the study, the temperature range of application of the oils was determined. The method of testing engine and transmission oils with cyclic temperature changes is presented, which allows comparing oils of the same purpose by the number of cycles of raising and lowering the test temperature, as well as identifying them for compliance with the classification according to performance properties groups.

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