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The paper aims to compare the CO2, CO, CH, and O2 concentrations in the exhaust gases of Cummins KTA 50 diesel engines of BelAZ 75131 mining dump trucks equipped with an onboard cryogenic fuel system and running on diesel and gas-diesel fuel at coal mines of Kuzbass (Russia). The research novelty lies in determining ecological efficiency when using liquefied natural gas (methane) as a motor fuel for heavy-duty mining dump trucks. In the near future, the use of this type of motor fuel will minimize the anthropogenic impact on the environment by reducing harmful emissions and provoking the environmental safety of the region where a large amount of mining equipment is used in coal mining enterprises. The demand for mining dump trucks, their operating conditions, and the world experience in converting mining equipment to liquefied natural gas (methane) were briefly analyzed. The use of alternative fuel sources for heavy-duty mining trucks is a promising way to reduce harmful emissions into the atmosphere. This paper presents a research technique. The data on the study of the CO2, CO, and CH groups and O2 concentrations in the exhaust gases of Cummins KTA 50 diesel engines of BelAZ 75131 mining dump trucks hauling rock mass are presented. The obtained data on the CO2, CO, and CH groups and O2 concentrations during diesel and gas-diesel operation of empty and laden BelAZ 75131 mining dump trucks when going uphill and downhill were substantiated. The results of calculating the average weighted emissions of the CO2, CO, and CH groups in the exhaust gases of Cummins KTA 50 diesel engines were presented.

Problem statement . The strength of cement stone has a significant impact on the properties of concrete. Therefore, much attention is paid to the formation of the structure and properties of cement stone. Improvement of the properties is achieved by activating the hardening of the cement paste in various ways. One of such methods is the processing of cement paste in electromagnetic field mixing with water or cement suspension of low concentration. When processing concentrated cement suspension in an alternating electromagnetic field, there is the intensification of dissolution, dispergation, hydration of the cement components and the formation of a cohesively dispersed structure of cement stone. The given paper gives research results of the impact of the processing concentrated cement suspension containing lime in an alternating electromagnetic field on hardening and strength processes of cement stone. The purpose of the article is to study the joint influence of alternating electromagnetic field and Са(ОН) 2 on the properties of cement stone. Conclusion . The impact of the alternating electromagnetic field on the concentrated cement suspension, containing Са(ОН) 2 as the result of synergetic effect enables to intensify hardening process and increasing the physical and mechanical properties of cement stone.

Problem statement. At the beginning of the week, in Ukraine the transfer is more significant in concrete consolidation. Especially important is the need to lower the supply of concrete and concrete, with the change in portability, without any loss of strength. The purpose of the article . For increased concrete and concrete strength, when changing the number of Portland cement, it is necessary to consolidate the various methods of the concrete concrete process. The most common are methods of heat exposure, as well as the use of various chemical additives. Electrophysical methods of influence are used to a lesser extent, namely intensification with the help of electric and electromagnetic fields. Purpose. To improve the quality and strength of concrete, while reducing the use of Portland cement, it is necessary to use various methods to intensify the concrete preparation process. Methodology. From the electrophysical methods of intensifying concrete preparation processes, the method of electromagnetic treatment of concentrated cement slurry, which was passed through an alternating electromagnetic field and was used to prepare the concrete mixture, is promising. Results. The performed tests showed that when an electromagnetic field is infused, a positive effect is induced to concentrate on a concentrated cement suspension in the process of structural adjustment and reduction of physical and mechanical power to concrete. It has been established that, as a result of processing, there is a greater variety, dispersion and better storage of cement and a form of cemented stone structure. Conclusion. Outlined above allows us to assert that electromagnetic processing of cement paste has a positive effect in the process of structure formation and the improvement of physico-mechanical properties of concrete based on the processed in the electromagnetic field of the cement paste.

The state-of-the-art of relevance and prospects of using alternative fuels for heavy-duty dump trucks as an effective way to reduce the anthropologic impact on the environment is considered. The analysis of the combination of factors (economic, technological, engineering, safety) determining the possibility and prospects of using alternative fuels in the operation of heavy-duty dump trucks in mining industry is carried out. The data are presented on the available experience of using environmentally friendly (alternative) fuels for heavy-duty dump trucks: electric energy, liquefied petroleum gas (LPG), com-pressed natural gas (CNG), liquefied natural gas (LNG). The studies conducted show that liquefied natural gas (LNG), for a number of objective reasons, seems to be the most promising alternative to diesel of all possible fuels in the segment of heavy-duty haulage vehicles. It is said that in Russia, in the Kemerovo region, for the first time, within the framework of one group of companies, an integrated project for the production of liquefied natural gas and its consumption by BelAZ heavy-duty dump trucks was successfully implemented.

Data are submitted of examination of 480 patients with myasthenia. The host protective mechanisms were studied, with the immunodeficiency (both cellular and humoral) having been ascertained. The above event were found out to be associated with severity of myasthenia, being more apparent in gravely ill patients.

In intravenous administration of magnesium sulphate, the postoperative shivering was cupped off in 87.8% of the patients. The mean effective dosage of the preparation was 32.2 mg/kg of body weight. In rapid intravenous administration of the preparation, in 3% of the patients, the nausea and vomiting+ occurred. Hypotension (3% of cases) and ++re-curarization of the mandibular muscles (3%) were eliminated by means of the intravenous administration of calcium chloride. Cupping off the shivering permitted to prevent the hypothermal reaction after the operation and narcosis.

Rotational analysis of theA 6Σ−X 6Σ (3-0 and 4-0) bands of crf was carried out. The anomalous spin-splitting in the upper states was interpreted by taking into account the combined effect of the centrifugal distortion and the perturbations by close lying6Π terms.