Ural State Mining University

The reliability of mine ventilation fans plays a crucial role in aerological systems and is determined by a combination of various geological, mining-technological, and structural factors, most of which are stochastic in nature. The problem of quantifying the reliability indicators of mine fan installations is addressed using various mathematical methods for modeling random processes. This study considers the possibility of applying Markov process theory to develop a methodology for calculating the operational reliability of centrifugal main mine ventilation fans, using the VShTs-16 as an example. The limitations of applying Markov processes to reliability analysis are demonstrated, particularly due to the condition of stochastic independence of failures. The use of homogeneous Markov processes has its constraints, since the transition intensities between individual system states are not always constant. In such cases, it is impossible to construct a system of differential equations with time-dependent coefficients. When stochastic dependence is present in failure flows of mechanical systems, the application of Markov process theory remains possible, but the most effective tool for reliability analysis in such cases is the Monte Carlo numerical simulation method.

The subject of the research is budgetary and debt instruments for ensuring sustainable development of the subjects of the Russian Federation. The purpose of the work is to assess the compliance of the instruments available to the subjects of the Russian Federation in the form of regional budget resources with sustainable development goals. Based on a comparison of the volume of budget resources of the constituent entities of the Russian Federation and the regional ranking indicators for achieving the Sustainable Development Goals, there is no direct link between budget revenue parameters and the results of activities in the field of sustainable development, meaning that any subject of the Russian Federation can successfully solve their tasks within the available capabilities. The article evaluates the compliance of expenditures of the budgets of the subjects of the Russian Federation according to the current budget classification with the goals of sustainable development and proves that based on the grouping of expenditures by sections of the budget classification, it is possible to verify only their indirect compliance. The directions of influence of regional budgets on the sustainable development of municipalities are determined. The assessment of debt instruments available to the subjects of the Russian Federation in modern conditions to ensure the achievement of sustainable development goals is given. It is concluded that the orientation of expenditures of the budgets of the constituent entities of the Russian Federation towards financing the Sustainable Development Goals implies an expansion of approaches to the classification of expenditures, as well as the development of accounting methods that will more clearly demonstrate the achievements of the regions in financial support of sustainable development.

The present paper considers the geological position and mineral composition of rare-metal (RM) pegmatoid metasomatic rocks, which form lenticular bodies. The single bodies of RM metasomatic rocks are spatially and genetically related to carbonatites. In addition, these bodies are spatially related with industrial vein, granular quartz bodies and have the same geological position. Unlike carbonatites, metasomatic rocks are crushed and boudined. These metasomatic rocks are unique due to the presence of unusually large xenotime crystals. Most minerals involved in the structure of these rocks contain abnormally high isomorphic yttrium impurity. In the composition of Y-bearing epidote and Y-bearing titanite, its amount is about 8 wt % Y2O3. Fergusonite-(Y) and a mineral with the idealized formula YAlSiO5 are present as inclusions in yttrium titanite. In apatite-II, which formed locally during recrystallization (granulation) of apatite-I, the total Y + HREE content significantly exceeds 10 wt %. Fergusonite-(Y) and a microinclusion, corresponding to a complex oxide with the formula Ca2Y2O5, are present as inclusions at the grain boundary of apatite-II. The unusual composition of metasomatic rocks and the specific structure of RM metasomatic rocks indicate a long process of their formation and metasomatic origin. At present, metasomatic lenses occur in rocks that experienced amphibolite-facies metamorphism.

The authors analyze the Palestinian-Israeli confrontation in the Gaza Strip and the growing tension in the Middle East region, as the main center of global instability, and offer their forecasts for achieving peace between the parties.

The paper presents the results of study of the magnetic structure of nonequilibrium gold–cobalt alloys obtained by high pressure torsion under different thermomechanical conditions in terms of temperature and strain magnitude. X-ray diffraction data analysis by Rietveld method has revealed incomplete dissolution of cobalt after 10 anvil revolutions at 300 K. In contrast, the same shear deformation at 80 K leads to complete dissolution of cobalt, accompanied by the formation of two solid solutions with different cobalt contents. The use of magnetic force microscopy has revealed that specimens subjected to mechanosynthesis at 300 K possess the stripe domain structure that is not observed in specimens after cryo-deformation. Vibrational magnetometry of the synthesized alloys has revealed a decrease in the saturation magnetization with increasing shear strain and decreasing temperature of mechanical alloying.

Abstract—Nitriding is the oxidation of UN-based nitride fuel by nitrogen at elevated temperatures. In this case, uranium mononitride UN is oxidized to sesquinitride U2N3, and the fcc structure of UN changes into a less dense bcc structure of U2N3, which is accompanied by an increase in mass by about 4% and an increase in fuel volume by more than 30%. The replacing one crystal structure with another and increasing the fuel volume lead to fuel fragmentation and the expansion of fuel-element cladding. The next operation is to remove part of nitrogen and to perform the reverse U2N3 → UN transformation (denitriding). Higher uranium nitrides are known to be unstable upon heating in an inert medium. The transformation from U2N3 to UN, which is again accompanied by a change in the crystal structure and a decrease in the fuel volume, occurs at elevated temperatures in an argon atmosphere. This process further contributes to the dispersion of fuel and its separation from fuel-element cladding fragments, the diameter of which was increased at the nitriding stage. Crushing of the fuel and a twofold change in its structure promotes the release of volatile fission products, such as inert gases, Cs, CsI, and Cd. Another advantage of this method is that nitrogen does not interact with the cladding and, hence, the cladding components do not pollute the fuel. In this work, the theoretical aspects of nitriding and denitriding are considered and thermodynamic modeling is performed. The next work in this series will present the results of an experimental test of the proposed method.