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The features of the oil-bearing capacity of the productive strata of Permian deposits in the interval of 117.5-188.6 m along the section of individual wells of the Ashal’cha field of heavy superviscous oil (Tatarstan) were revealed depending on the content, composition, and thermal effects of organic matter (OM) oxidation in the rocks. It is shown that the rocks are very heterogeneous in their mineral composition and in the content of both free hydrocarbons by extraction with organic solvents and insoluble OM closely associated with the rock. The total content of OM in rocks varies from 1.72 to 9.12%. The features of group and hydrocarbon composition of extracts from rocks are revealed depending on their mineral composition and the content of organic matter in them. According to the molecular mass distribution of alkanes of normal and isoprenoid structure, extracts from rocks are differentiated according to three chemical types of oil: type A1, in which n-alkanes of composition C14 and above are present, and types A2 and B2, in which n-alkanes are destroyed to varying degrees by processes microbial destruction, which indicates a different intensity of biochemical processes in productive strata of Permian sediments. These processes lead to a decrease in the amount of OM in the rocks and an increase in the content of resins and asphaltenes in the oil extracted from them, as well as an increase in the viscosity of the oil. Using the method of differential scanning calorimetry of high pressure, it was found that the studied rock samples differ from each other in quantitative characteristics of exothermic effects in both low-temperature (LTO) 200-350°С and high-temperature (HTO) 350-600°С zones of OM oxidation. The total thermal effect of destruction processes of OM depends on the content of OM in the rocks and its composition. The research results show that when heavy oil is extracted using thermal technologies, the Permian productive strata with both low and high OM contents will be involved in the development, and the general thermal effect of the oxidation of which will contribute to increased oil recovery.

In the article titled “The Oil-Bearing Strata of Permian Deposits of the Ashal’cha Oil Field Depending on the Content, Composition, and Thermal Effects of Organic Matter Oxidation in the Rocks” [1], the first author, Galina P. Kayukova, and corresponding author, Dr. Alexey V. Vakhin, requested to remove the second affiliation, “Institute of Geology and Petroleum Technologies, Kazan Federal University, Kazan 420008, Russia,” for the first author Galina P. Kayukova.

Safe separation of the rocket payload fairing is one of the most important factors that affect the success of a flight mission. In recent years, composite materials instead of aluminum alloys are widely used in rocketry. Such materials must satisfy a number of requirements that include the certainty of a local failure due to the action of a cumulative charge of the given power. To analyze this process numerical research is an advisable approach. The model of a composite rocket fairing separating due to the action of a cumulative charge has been developed. The properties of the composite material have been modeled based on the averaged characteristics obtained experimentally. The cumulative charge has been modeled by impulse loading having parameters adequate to the charge type. The time of action of the impulse, maximum pressure and width of the loading area are determined from the charge properties and geometry. The rocket fairing is considered as a composite shell composed of conical and cylindrical parts. A technique for 3D numerical analysis of the dynamic strength and structural failure has been developed. The mathematical model of the structure deformation and failure takes into account the dynamical properties of the material. The maximum plastic deformation is used as a failure criterion. The results of numerical simulation for the typical rocket payload fairing are presented.

Modern rocketry widely employs a method of gasodynamic impulse destruction of bondings which may occur at high variety of temperatures. To design fasteners correctly it is necessary to have the ability to calculate fastener’s destruction time at a given pressure. Numerical research is an expedient approach to this problem. A mathematical model of a high-speed deformation and failure in fastening elements of special rocket structures due to gasodynamic wave-impact impulse loading is developed. A technique for numerical analysis of the deformation of fasteners and failure duration is proposed. To perform such analysis a set of factors such as: static stress-strain state due to assembling; thermo-elastic deformation of fasteners due to environment temperature; high-speed dynamical elastic-plastic failure of fastening elements are taken into consideration. The failure model due to the plastic flow considers dynamical material properties. As a criterion of failure maximum plastic deformation is chosen. The technique is implemented for several types of fasteners. Numerical simulation using finite elements method is conducted. The results of the numerical research are well-correlated with experimental data.

On the example of 50 heavy oil fields prepared by PJSC ?Tatneft? for pilot development in the territory of Tatarstan, the relationships of the changes in their properties: density, sulfur and paraffin content with the oil-bearing area, effective average oil-saturated thickness of reservoir productive rocks, as well as with coefficient of their sand content, permeability and porosity were investigated. The analysis showed differentiation of technological properties of heavy oils within the same productive layers, characterized, in turn, by heterogeneity of oil-generation and filtration-capacitive characteristics. Average oil-saturated effective thickness of the seams and the area of their oil-bearing capacity at their maximum and minimum values practically do not coincide. For most of the deposits, the density of the oil decreases with increasing bed depth and oil reservoir area, but does not depend on their average effective oil-saturated thickness. The smaller the depth of productive rocks, the more their permeability. However, the porosity of productive layers is not directly dependent on the depth of their occurrence, which indicates a complex and heterogeneous structure of reservoirs within the structural zones of the Permian system. The coincidence of these two parameters, according to the maximum values, is observed only in individual oil fields, including Ashalchinskoye and Mordovo-Karmalskoye, which is currently in experimental development, which indicates the distinctive conditions for the formation of hydrocarbon deposits in them. Clear dependences of the change in the density of the investigated oils, the content of sulfur and paraffin in them from the filtration-capacity properties of the rocks were not revealed. The main part of the oils of the investigated sediments is characterized by low paraffin content (0.07-3%). Only a clear differentiation of crude oil by technological parameters into two groups is revealed by their belonging to rocks differing in the values of the coefficient of sand content. Thus, the conducted studies have shown that the oil and bitumen formation process in the surface sediments of the sedimentary thickness of the Permian system is a region of complex phenomena occurring under the influence of difficultly controlled factors, leading to a disruption of the regular relationships between the fluid parameters under study and with parameters of sediments containing them. These features of the formation of hydrocarbon deposits of specific deposits should be taken into account when choosing the directions of geological exploration and the methods of their development.

Featuring a number of distinguished essays by internationally known Russian cultural historians Boris Uspenskij and Victor Zhivov, this collection encompasses various ground-breaking works appearing in English for the first time. Focusing on several of the most interesting and problematic aspects of Russia’s cultural development, these essays examine the survival and reconceptualization of Russia’s past in later systems, and some of the key transformations of Russian cultural consciousness. This volume contains important examples of cultural semiotics and indispensable contributions to the history of Russian civilization.