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Thermobaric conditions in oil and gas wells require the use of backfill materials with special physical and chemical properties. Cement composites are subject to the requirements of fluidity (to ensure uninterrupted delivery to the cementing site), timely formation of the necessary mechanical strength (to prevent the interaction between the cement glass and reservoir fluids), corrosion resistance, impermeability and durability. Therefore, the composition of the cement slurry should be selected based on the mining and geological characteristics of the well.Wellbores wall are reinforced with protective pipes, which are attached to the well with cement or cement slurry. It is needed to protect wellbores wall from rock falls, gas, oil and water shows and to isolate productive formations. If this operation is carried out qualitatively, then the outer part of the casing string will be protected from the impact of the formation fluid. Otherwise, pipe corrosion may occur, which can lead to the destruction of the cement stone and, as a result, to accidents.

It draws our attention to the processes of interaction between the well and the penetrated permeable formations during its construction, which are largely determined by geological and thermobaric conditions, types of fluid saturating the formation, used technologies and technical means. The article deals with the main problems of well construction intended for the high-viscosity oil production. Laboratory and experimental studies have been conducted to solve these issues, they will help to scientifically substantiate and implement new technologies and technical means to increase productivity and durability of wells intended for production of high-viscosity oil from productive formations with complex thermobaric conditions. In this work, the authors conducted a study of the formulations of flushing fluids to penetrate productive horizons with high-viscosity formation fluids. Based on the results of the laboratory tests, it was decided to use a fresh polycationic solution.

The features of nonstationary heat transfer of one layer of balls of the same size were studied in a fixed layer of liquid. The experiments were carried out in a cylindrical thermostat with a diameter of 128.9 mm filled with glass balls of 8.9 and 16.0 mm diam and polyoxymethylene balls of 9.0 mm diam with the highest possible packing density. The ball packing was filled with distilled water to a level of 0.1-0.2 mm higher than the ball diameter. The temperature of the ball packing surface was measured using a NEC 7100 thermal imager with a step change in temperature at the outer boundary of the packing. It is shown that, for a monolayer of balls of the same size in a stationary liquid, the temperature field is symmetrical relative to the packing center and the value of the effective thermal conductivity coefficient is constant over the packing cross section, both during heating and cooling. It has been found that the heat transfer coefficient and the time for establishing thermal equilibrium of a ball packing in a layer of stationary liquid at the same temperature difference depend on the heat flux direction at the packing boundary. The numerical values of the characteristic time of thermal equilibrium establishment in the heating and cooling regimes differ from each other by several times; whereas in the water layer without balls, this difference does not exceed 30%.

On the basis of metallographic analysis and test results of samples of welded junctions of aluminum alloys AMg6 and D16T, made by friction stir welding, for static stretching, it is shown that destruction occurs in the zone of thermo-mechanical action for the AMg6 alloy and in the zone of thermal influence for the D16T alloy. At the same time, the dependence of the temporary resistance value of the welded junction on the state of the seam weld face has not been revealed. Tests for low-cycle fatigue have shown that the endurance limit is clearly dependent on the amount of seam weld face roughness. The value of the roughness of the seam weld face for the studied alloys has been determined, in which the nature of the fracture during the low-cycle fatigue test changes from multi-stage to single-stage.

This article contains the microparticle accelerator scheme, the methods, and the results of practical study of magnetic field induction and electromagnetic radiation formed during explosion product ionization and energy accumulation during explosive charge detonation, as well as the influence of some process parameters on its change. The purpose of this work is to study the influence of accelerator energy parameters and silicon carbide microparticle sizes on the change in magnetic field induction during their acceleration. The influence of technological parameters on the electrodynamic properties of the ionization process of a complex chemical system, which is condensed EXPLOSIVES, was studied by the developed method based on the Hall effect with the use of the developed semiconductor Hall sensors and a special measuring complex. The average magnetic field induction value is 48 MT. The influence of the energy parameters of the accelerator (explosive charge mass), as well as of the size of microparticles introduced into the explosion products (PV) on the electrodynamic properties of the processes of ionization and acceleration of microparticles was determined by measuring and calculating magnetic field induction. Practical results were obtained and confirmed the particle size influence on the plasma state. With an increase in the particle size from 20 to 100 microns, the induction value increases to 50 MT and decreases sharply with a change in the size from 150 to 300 microns. The obtained dependences are the technological characteristics of the process of processing materials by high-speed flows of microparticles with the use of explosion energy, which can be adjusted to make the process manageable.

The article discusses the main technological processes of well construction for the production of high-viscosity hydrocarbons from productive lowporosity reservoirs with high temperature and pressure conditions, which include shale deposits of Bazhenov formation. According to the results of the review and analysis of existing solutions in the development of this deposits, the following measures were justified and proposed: construction of branched multi-hole azimuth horizontal wells, implementation of selective multi-stage hydraulic fracturing in the productive formation; the use of oil-based process fluids when opening the reservoir, the use of plugging materials for isolation of the reservoir, the hardening product of which is represented by thermally stable hydrate phases (hydrobasic hydrosilicates). Вranched wells have a long horizontal end (about 1 000 meters or more). Only a part of the horizontal section works effectively, which is the basis for the development and application of the staged, both in time and along the strike, hydraulic fracturing method. At the level of the invention, a method and apparatus for carrying out multistage selective hydraulic fracturing in wells with horizontal completion have been developed. The article describes a method for implementing multistage selective hydraulic fracturing, comparing this method with the existing ones. Much attention is given to the need to use hydrocarbon-based solutions for the initial opening the reservoir, to use cement slurries from composite materials to separate the reservoir, the hardening product of which is a stone formed by low-basic calcium hydrosilicate.

The article presents the results of studies of titanium alloy VT20 in ultrafine-grained (UFG), subfine-grained (SMG), fine-grained (MZ) and mesopolycrystalline (MPC) states, obtained, including by methods of plastic deformation and subsequently subjected to ion implantation. The effect of grain size on the structural-phase state of the titanium alloy surface and mechanical properties is shown.

The article presents the results of the influence of the structural state of titanium alloys VT1-0 (α-alloy), VT20 (pseudo-α-alloy), VT6 (α + β) -alloy of the martensitic class) and VT15 (pseudo-β-alloy) on the penetration depth ions of nitrogen, aluminum, copper and the cathode of the alloy 50% Cu – 50% Fe. It is shown that the structural class of titanium alloys selected for the study, when exposed to ion implantation by both gases and metals, does not significantly affect the depth of their penetration.

It is shown that the appearance of foreign metal inclusions in the seams of aluminium alloys created by friction stir welding is a consequence of the interaction of the working tool with the metal ...

The significance of the study of philosophic aspects of building a new game universe in an RPG, abbreviation for a role-playing game, stems from the popularity of this type of virtual reality entertainment. The paper gives an analysis of the anti-world, a key concept of role-playing gaming, basing on the RPG project The Witcher (Ved’mak). The game is founded on the original series of works under the same title created by Polish fantasy writer Andrzej Sapkowski. The case under consideration serves as a good example for looking into the patterns of forming the space of the game universe that can be equally regarded as a moment when a cultural landscape of virtual entertainment is formed. In this case, RPG can be considered as a socio-cultural practice of the global information society and/or one of the variants of the performance society. The methodological basis of the study is comparative analysis, which implies the identification of borrowings in the process of developing a culture of virtual entertainment and requires learning about basic cultural codes and archetypal designs that are specific to RPG. As a result of the research, the specificity of the new imagery form inherent in the game universe of The Witcher was revealed. The cultural landscape created in the game includes elements of the medieval laughter culture integrated into the unique system of dynamic images and meanings, constantly evolving and functioning in a way analogous with the established cultural and symbolic reality. The effect of the double symbolic analogy is determined by the creative nature of the game, in which players in addition to participating in the gaming process also contribute to the creation of the game. The introduction of game images into the language and thinking of the players causes the emergence of new forms of dialects, fixing the peculiarities of perception by the group (sociolect) and the individual (idiolect) of both primary and secondary reality. These dialects are geographically localized and at the same time multicultural. The article substantiates the conclusion that the instrumentalization of the performance society occurs due to the active use of grotesque symbolism, which, due to its archetypal nature, ensures the formation of a new social mythology that enables the discovery of Eastern Europe by the rest of the world. Thus, the anti-world of the new universe turns into an integral part of the modern information space.

The mechanical properties and the structure of the butt joints of Al–Mg–Si alloys made by friction stir welding are investigated. The ultimate tensile strength of the joints is found to be 0.82–0.87 depending on the alloy grade after welding. Fracture is shown to occur through the thermomechanical action zone on the side of tool motion. The bending angle of the joints (170°–180°) significantly exceeds the values typical of fusion welding. The hardness distribution in the joints has a W-shape characteristic of these alloys. Artificial aging after welding is shown to cause an increase in the strength coefficient of the joints to 0.92–0.96 at a bending angle of 160°–170°. Complete heat treatment, including quenching and artificial aging, is found to cause noticeable buckling of the welded joints and to be accompanied by a decrease in the strength and plastic properties of the joints because of grain growth in the mixing and thermomechanical action zones. After this treatment, the microhardness distribution within the welded joints is found to decrease and level off.

The article presents studies of the structure and phase composition of aluminum alloys after ion implantation. It is shown that the effect of accelerated ions (Cu + Pb) (E = 30 keV, j = 100 μA / cm2) on an alloy without a cladding layer already at a dose of 1016cm- 2leads to the formation of a developed subgrain structure in the initially deformed alloy. With an increase in the ion current density and radiation dose, the cellular structure of the implanted aluminum alloys becomes more regular - well-formed cells are observed practically throughout the entire volume of the sample under study. The average width of the dislocation-free regions reaches 2.5 μm with the width of the boundaries not exceeding 0.6 μm.

The effect of high-dose aluminum implantation on the structural-phase state of the surface layer of titanium alloy VT6 with a fine structure (average grain size 2.3 μm) on the mechanical and corrosion properties has been investigated. It is shown that, as a result of ion irradiation, polyphase implanted layers based on α-titanium grains are formed, containing an intermetallic Ti3Al phase along the grain boundaries of α-titanium. The modified surface layers are characterized by improved mechanical properties and corrosion resistance. The noted effect is enhanced by the use of preliminary helium implantation with a dose of 1.3 × 1017ion / cm2.

The article considers the motor activity of non-physical students in conventional and distance learning. The importance of the discipline “Physical Culture and Sport (Selective Discipline) is shown” in terms of the formation of physical culture of the individual, the ability to target the use of physical culture and sports in order to promote health. A comparative analysis of the weekly volume of motor activity of students, the duration of training sessions, shows the most popular types of independent physical education classes before the introduction of restrictive measures related to COVID-19 and during distance learning.

The theoretical and experimental data determining the similarities and differences between the defect formation processes under the conditions of neutron and imitation ion irradiation are analyzed. The analysis involves such factors as the type and energy of cascade-forming particles, the composition and structure of irradiated materials, and the irradiation temperature. A number of proven procedures for calculating the concentration of radiation defects and the number of displacements per atom for cascade-forming types of irradiation are revised. The key factors ensuring the similarity of full-scale and simulation experiments are considered, with the following two of them singled out as the principal factors: the damaging dose accumulation rate (flux) and the temperature, which determine the course of relaxation processes. Simple methods are proposed for estimating the number of primary knocked-on atoms (PKA) under neutron irradiation and the fraction of elastic energy losses spent on defect formation. The substantiation of a unified fractal structure of atomic displacement cascades in a given target is provided, regardless of the nature and energy of the cascade-forming types of irradiation.

The effect of 15-keV Ar+ ions on the structure of austenitic chromium-nickel steel in the 3.1 × 1017–7.5 × 1017 cm–2 fluence range has been investigated in this work. X-ray diffraction analysis indicates a nonmonotonous change in the lattice parameter and the level of microstresses in some crystallographic directions with increasing fluence. The anisotropy appearance of these stresses gradually decreases and the texture becomes weaker. These processes are associated with radiation defects at the initial stage of irradiation and their radiation-induced annealing as the fluence increases. Transmission electron microscopy has revealed atomic separation in the solid solution and a decrease in the dislocation density in the steel starting from a fluence of 5 × 1017 cm–2 (40 dpa). Similar data have been obtained when steel of a similar composition has been exposed to high-energy ions. No pore formation has been detected under the used irradiation conditions, since the swelling threshold (according to known estimates, ~70 dpa) has not been reached.

To study the influence and selection of rational elastic-dissipative parameters for under wing pylon-mounted engine suspension, a mathematical model of aeroelasticity of a large-sized transport aircraft has been developed by taking into account the kinetic moment of the engine rotors and specially designed engine attachment points to the pylons. It is shown that the elastic-dissipative parameters of the attachment points, which implement the concept of a released engine, have a significant effect on the integral aeroelastic and strength characteristics of the aircraft. Schematic diagrams of the engine mounts to the pylon are proposed. The usefulness of the concept of a released engine for increasing aeroelastic stability and reduce the level of fatigue damage of the aircraft structural elements has been proved.

Transient processes are experimentally investigated at the initial stage of heat and mass transfer with steam absorption on the surface of 57.8 % water solution of lithium bromide in a bath with a diameter of 70 mm. The experiments were carried out both with a pure solution and with a solution where n-octanol surfactant was added. It is shown that with a sharp steam pressure increase in the volume above the surface of an absorbing solution, local temperature inhomogeneities are generated on the solution surface. The growth rate of these inhomogeneities is proportional to the growth rate of the steam pressure. It was found that, in contrast to the solution without surfactant, where convective flow is observed only during a short time interval after steam supply to the absorber, in a fixed layer of water-LiBr solution with surfactant addition, there is stable thermocapillary convection in the near-surface layer of solution during absorption. It is shown that for variable bottom topography, there can be space-localized zones, where the temperature on the solution surface is determined by the shape of bottom topography.

The article considers the effect of ultrasonic exposure after the ion implantation of titanium alloys VT1-0 and VT6 silver on the thickness of the ion-leged layer, the distribution of silver by the thickness of this layer and the scalar density of dislocations in the subsurface layer. It has been established that for the alloy VT6 at the same parameters of the implantation regime there is a deeper penetration of silver ions compared to the alloy VT1-0. Directly under the ion-leged layer is formed a layer with an increased rocky density of dislocations. The ultrasonic treatment of the implanted layer on the alloys studied contributed to the deeper penetration of silver ions and the alignment of its concentration by the thickness of the surface layer of titanium alloys.

A study was carried out on the photovoltaic and photoconductive properties of fi lm composites of a styrene copolymer with nonyl methacrylate and polyNepoxypropylcarbazole doped with lanthanide complexes Ln2L6·PS (Ln = Nd, Eu, Gd, Yb), HL is the carbacylamidophosphate ligand, CCl3C(O)N(H)P(O)(NEt2)2, N-[bis(diethylamino) phosphoryl]2,2,2-trichloroacetamide; PS is 3,6-dipyridin-2-yl-1,2,4,5-tetrazine, C5H4N–C2N4–C5H4N). In the visible spectral range, these composites were found to have holetype photoconductivity. The internal photoelectric effect is a function of the photogeneration of charge carriers from the metal complex molecules and the sensitizer. EPR was used to study the kinetics of the formation and relaxation of the photogenerated charge carriers. We conclude that the metal complex molecules in the polymer composite enhance the efficiency of photogeneration of nonequilibrium charge carriers and thereby affect the photovoltaic properties of the composites.

The interaction of a charged particle and a rotating fullerene molecule in a fullerite crystal is investigated. The mathematical model was constructed and implemented for fullerene rotation frequencies up to 1014Hz and velocities of an incident charged particle of the order of 103m s1. The study was carried out using the methods of classical molecular physics. The characteristics of the motion of the C 60 fullerene molecule were determined using the laws of classical mechanics, Euler ’ s approach, and a step-by-step numerical method of a high order of accuracy. The influence of the action of a charged particle on the nature of the motion of a rotating fullerene was analyzed according to the results of the performed numerical experiments.

—The magnetoresistive characteristics of magnetic metallic Fe/Cr and Co90Fe10/Cu superlattices subjected to irradiation with accelerated Аr+ ion beams with an energy of 10 keV at the fluences F = 1013–1016 cm–2 are studied in this work. It was found that, at F ≤ 6 × 1014 cm–2, the studied superlattices retain their functional characteristics. Causes for a decrease in the magnetoresistance of superlattices with a subsequent increase in the fluence are discussed. It was concluded that the radiation stability of the advanced modern Co90Fe10/Cu superlattices is higher than that of the model Fe/Cr superlattices.