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We studied the cytotoxic effect of gadolinium nanocomposite on cultured mouse fibroblasts 3T3-SV40 and histological changes in the liver tissue of albino rats after its administration. For in vitro experiment, gadolinium nanocomposite on the natural matrix of arabinogalactan (nGd-AG) was dissolved in DMEM nutrient medium to concentrations of 0.005, 0.02, 0.5, 2, and 5 mM. In in vivo experiment, a nGd-AG solution was orally administered to rats through a tube in a dose of 500 μg Gd/kg in 1 ml of 0.9% NaCl for 10 days. The pattern and degree of influence of the gadolinium nanocomposite on the studied cell culture depended on the concentration and duration of exposure. IC 50 of nGd-AG determined after cell incubation for 24, 48, and 72 h were 616 μg/kg (3.9 mM), 302 μg/kg (1.9 mM), and 222 μg/kg (1.4 mM), respectively. Histological changes in the liver of white rats induced by exposure to nanocomposite attested to the development of a compensatory reaction of the organ.

The article is devoted to the use of residual products of combined thermo- and hydrocracking of heavy resid and vacuum gas oil into high-demand marketable petroleum products (into bitumen products) in conformity with Russian and international quality standards.

The article is devoted to the experience of TAIF-NK JSC in the field of efficient, environment-friendly, and technological processing of residual products of combined thermo- and hydrocracking process with a comparative analysis of the merits and demerits of each method. It is shown experimentally that, taking into account the specific features of the residual products of hydrocracking and the associated increased tendency to precipitation of asphaltenes and coking, it is necessary to carry out further processing of residual products under milder conditions in order to get products that are in demand in metallurgy.

The article is devoted to experience of TAIF-NK JSC in use of combined thermo- and hydrocracking process for conversion of oil distillation heavy residues (heavy resid and vacuum gas oil). As a result, the TAIF-NK JSC complex for heavy residue processing is the only one in the world, which allows heavy residue conversion with maximum yield of high-quality light oil products. Implementation of the VCC-based combined thermo- and hydrocracking process at TAIF-NK JSC refinery complex ensured 85.1 % conversion depth and 80.7 % yield of light oil products in 2021. The dynamics of the indicators of oil conversion depth and yield of light oil products due to implementation of the process are reviewed.

An asymmetric satellite equipped with control momentum gyroscopes (CMGs) with the center of mass of the system moving uniformly in a circular orbit was considered. The stability of a relative equilibrium attitude of the satellite was analyzed using Lyapunov’s direct method. The Lyapunov function V is a positive definite integral of the total energy of the perturbed motion of the system. The asymptotic stability analysis of the stationary motion of the conservative system was based on the Barbashin–Krasovskii theorem on the nonexistence of integer trajectories of the set , which was obtained using the differential equations of motion of the satellite with CMGs. By analyzing the sign definiteness of the quadratic part of V , it was found earlier by V.V. Sazonov that the stability region is described by four strict inequalities. The asymptotic stability at the stability boundary was analyzed by sequentially turning these inequalities into equalities with terms of orders higher than the second taken into account in V . The sign definiteness analysis of the inhomogeneous function V at the stability boundary involved a huge amount of computations related to the multiplication, expansion, substitution, and factorization of symbolic expressions. The computations were performed by applying a computer algebra system on a personal computer.

The proposed methodology has been developed in order to focus on the search for a specific failed track element and rolling stock or other inconsistency, as well as the technological component of ensuring the transportation process (placement and fastening of cargo, formation of train composition, choice of train driving mode) on the quality of functioning, which depends on the prevention of gatherings. In the developed methodology, the types of technical component, technological components or the corresponding groups of causes of rolling stock derailments indicated above are called classes. The class distribution can be attributed to a statistical classification, i.e., during an internal investigation, the data of each class K (“path”, “wagon” and “locomotive”) They can be represented by a set of pnk parameters of the next descent, which are input data for solving the classification problem. The result of solving this problem should be the attribution or degree of involvement of each of the classes in a specific meeting.

The technique provides an analytical criterion for selecting the one set of numerical data most involved in an emergency out of several ones which are the relative deviations of the main factors from the critical ones in transport. The criterion is based on finding the theoretical left boundary of the interval of each set of deviations. The sets under study are reduced to normal distribution laws using a well-known method. The analysis uses basic numerical characteristics similar to those used in probability theory and mathematical statistics. The proposed method is based on finding the central theoretical moments up to the third order inclusive. Explanatory demonstration examples are provided.

When burning fuel in a diesel internal combustion engine, soot is an undesirable product. To reduce the soot content in the exhaust gases, it is necessary to know the physical and chemical bases of the process of soot formation and soot burnout. Due to the determining role of acetylene in the formation of polycyclic aromatic hydrocarbons in rich mixtures in the low-temperature zone and the key role of acetylene in the surface growth of a particle in the high-temperature zone, it is concluded that the rate of surface growth of a particle is proportional to the concentration of acetylene in the reaction zone, which can be determined by the gas-kinetic method, numerically solving a system of differential equations for the components of the gas mixture under consideration.

We studied the reproductive function of albino male rats after long-term exposure to wildfire smoke and the species-specific behavior of their sexually mature offspring. After the end of exposure, the mean number of spermatogonia and the relative number of Leydig cells in rat testes decreased and the index of spermatogenesis decreased. The offspring of exposed males mated with intact females demonstrated impaired cognitive abilities and disturbances of species-specific behavior. The severity of these changes depended on time interval between the end of the inhalation exposure and mating.

The article presents a comparative assessment of various processes of demetallization of heavy petroleum feedstock (HPF). By the example of TAIF-NK JSC, which operates a slurry hydrocracking unit based on VCC process, the possibility of mastering secondary processes aimed at deepening oil refining is shown.