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The method of acid hydraulic fracturing has been actively used in recent years, for the deposits of the Vereysky horizon of the Moscowian strata in the south-east of Tatarstan. Design development and the use of hydraulic fracturing requires full-fledged studies of the geomechanical characteristics of rocks, including the prediction of the propagation of emerging fractures. It is considered the main geomechanical characteristics for reservoir rocks and dense rocks involved in the structure of the sections, on the example of the study of polyfacial reservoirs of the Vereysky horizon of the Ivinskoye oil field. It was revealed that the carbonate reservoir rocks of the middle and upper parts of the Vereysky horizon (C2 vr3 and C2 vr5) have the least strength properties and a greater susceptibility to fracturing. More durable were sandstones of the upper part of the horizon, marls and mudstones of the middle and upper parts of the horizon, as well as mudstone and dense packstone, typical for the lower part of the Vereysky horizon. The presented data can be valid for most of the sections of the Vereysky horizon of the southeast of Tatarstan and are used for the choice of optimal solutions when applying the hydraulic fracturing technology.

Domanic type deposits generally is abundant in Tatarstan Republic and other territories. They are feature with oil-source rocks (black shales), which partly generated hydrocarbons. However, due to their high hydrocarbon contain, domanic type deposits construing as unconventional reservoir rocks, that may be commercial significant. Based on Russian and foreign experience in the development of such deposits, the prospects for their exploitation are associated with the searching for formations with increased reservoir properties and light oil.In this work we are analyzed the stratigraphic distribution of domanic type deposits in the Kama-Kinel system of depressions and beyond them. It is shown that such deposits in the Kama-Kinel system of depressions have a thickness about 300 m and cover the stratigraphic range from semiluk horizon of the Frasnian stage to Tournaisian stage. But out of depressions these rocks occurred only in semiluk horizon. The reason of it is high dissection of the bottom of the Domanic sedimentation basin in the Late Frasnian-Tournaisian ages due to the evolution of the Kama-Kinel system of depressions in the east of the Russian Plate.The results of our own research show that carbonate and carbonate-siliceous rocks enriched in organic matter are the most common lithotypes in the Domanic type deposits. Also, we constantly found carbonate breccias and less secondary dolomites in the studied geological columns. In the last two types of rocks, we found higher values of porosity, openness, and a lighter composition of hydrocarbons. Based on the results of the author’s research and the literature observation, it follows that the development of carbonate breccias and secondary dolomites will be in the sides of the Kama-Kinel system of depressions. We consider that they are as the most promising objects for the search for industrial profit in the Domanic type deposits.

The results of integrated sedimentology, petrography, and petrophysical study of the Upper Devonian (Middle Famennian) Dankovo-Lebedyansky carbonates from Southeast Tatarstan of the Volga-Ural Basin revealed a variety of microfacies and diagenetic events that impacted the reservoir quality. Although our earlier study documented microfacies analysis and depositional environments, none of the studies focused on diagenesis, microfacies interaction, and their controls on the studied sediment's reservoir quality. Based on petrographic and microfacies analyses, the seven identified microfacies types are peloidal grainstone MF 1, cemented bioclastic peloidal grainstone MF 2, echinoderm-concentrated packstone MF 3, algae packstone MF 4, bioclastic wackestone MF 5, whole-fossil wackestone MF 6, and dolomite MF 7. For the investigated sediments, a gently deepening carbonate ramp depositional model with an inner, middle, and outer ramp setting is proposed. The observed diagenetic events in this study include micritization, calcite cementation (six cement types), dolomitization (six dolomite types), dissolution (fabric and non-fabric-selective dissolution), compaction, and microfracturing. The identified microfacies were classified into three distinct classes based on their petrophysical characteristics. MF 1 and MF 7 are microfacies types with the best reservoir quality. MF 3 and MF 4 are microfacies types of moderate reservoir quality. MF 2, MF 5, and MF 6 are microfacies types with poor or non-reservoir quality. Calcite cementation, micritization, and compaction are the primary diagenetic modifications responsible for porosity reduction. Moldic pores created by dissolution are a significant porosity-improving process. Porosity is locally enhanced by stylolite and microfractures. Dolomitization improved reservoir quality by creating intercrystalline and vuggy porosity. Understanding the impact of microfacies and diagenesis on reservoir quality is crucial for understanding reservoir properties in nearby fields with similar settings.

The Upper Devonian, Middle Famennian Dankovo-Lebedyansky sediments in Southeast Tatarstan territory are a carbonate sequence composed of limestone and dolomite, which is important hydrocarbon reservoir units, therefore, it is necessary to conduct in-depth study on its microfacies and depositional environment. In this study, a multidisciplinary approach that combines core observation with thin section examination is used. The limestone contains abundant skeletal grains (echinoderms, foraminifera, algae, gastropods, and calcispheres), as well as non-skeletal grains (intraclasts and peloids). On the basis of detailed petrographic investigations, six sedimentary microfacies can be identified, including (i) peloidal grainstone (MF 1), (ii) cemented bioclastic peloidal grainstone (MF 2), (iii) echinoderm-concentrated packstone (MF 3), (iv) algae packstone (MF 4), (v) bioclastic wackestone (MF 5), (vi) whole-fossil wackestone (MF 6), as well as dolomite or dolostone as diagenetic facies (MF 7). Based on microfacies analysis, the Dankovo-Lebedyansky sediments were deposited in three distinct sedimentary facies belts (shoal, lagoon and open marine environment). In order to reflect dispositional energy condition, the microfacies were grouped into facies associations: (i) low-energy microfacies associations including MF 5 and MF 6, (ii) moderate energy microfacies associations including MF 1, MF 2, MF 3, and MF 4. The dolomite, or diagenetic facies (MF 7), is the result of slightly to extensively dolomitization of limestone in the Dankovo-Lebedyansky sediments. Most of frequent dolostone types are euhedral planar-e and subhedral planar-s. According to petrographic characteristic of the dolostone, a seepage reflux model can be used to explain the dolomitization process of Dankovo-Lebedyansky sediments.

The article shows the main types of structures of the porosity of the Tournaisian reservoirs from the southeast of Tatarstan. The main type of pore space is intergrain porosity, while the fractures have a subordinate significance. They are analyzed in detail main factors of the origin of the pore space of the Tournaisian reservoir rock. There are include depositional, diagenetic, structural and tectonically factors. The depositional factor is the selectivity of rock types as reservoirs, only two lithological types of limestone have industrially significant reservoir properties and represented by peloidal and crinoid-peloidal packstones. The diagenetic factor realizes via secondary leaching of carbonate rocks during burial diagenesis of rocks. Leaching processes provide the main increase in rock porosity. On the one hand, the structural and tectonic factor provides the possibility of oil charge in the structure, on the other hand, it shows the heterogeneity of the distribution of porosity depending on the position of the reservoir rocks on the structure. The highest porosity values are characteristic for the crest part, lower for the flanks and minimal for the deflections of the oil-bearing structures.

The work carried out a study of core material from oil source rocks of the Sarailinsky depression, located between the southern and northern domes of the Tatar arch within the Tatarstan Republic. The well sections of the Sarailinsky strata are dominated by carbonate rocks, represented by packstones, wackestones and mudstones. Among the limestones lie interlayers of carbonate-siliceous rocks and mudstones. All rock lithotypes are enriched to varying degrees in sapropelic organic matter, which allows them to be classified as oil source deposits. There is a tendency for the relative content of organic matter to increase in the series: limestone → carbonate-siliceous rocks → mudstones. Judging by the interlayering of rocks of different composition in the section, the formation of the Sarailinsky strata took place in a marine sedimentation basin, with periodically changing environmental conditions. Under normal conditions, limestone was formed, under abnormal conditions, carbonate-siliceous rocks enriched in organic matter were formed, and when the removal of terrigenous material from the continent intensified, argillites were formed.

We present a simplified version of an average-atom collisional-radiative model employing both local-thermodynamic-equilibrium average-atom and isolated-ion atomic data. The simplifications introduced do not lead to any substantial errors, and they significantly speed up calculations compared with the basic average-atom model involving direct solution of the self-consistent-field equations. Average ion charges, charge state distributions, and emission spectra of non-local-thermodynamic-equilibrium (NLTE) gold plasmas calculated using various modifications of the average-atom collisional-radiative model are compared with those obtained using the THERMOS model with the detailed configuration accounting approach. We also propose an efficient method to calculate thermodynamic functions of NLTE plasmas in the context of the simplified average-atom collisional-radiative model.

One of the strategic ways of the old oil-producing regions is to further prospecting for potentially promising areas for hydrocarbon. One of these exploration areas is the Volga-Ural region. These reservoirs consist of Carboniferous carbonate rocks, which contain high viscous hydrocarbons and are characterized by complex facies architecture and reservoir properties influenced by diagenesis. The high degree of facies variability in the studied area does not allow reliable distribution of potential reservoir rocks not only between different areas but even within the same oil field. Based on textural and compositional features of carbonate facies, 5 main facies associations were identified and characterized with respect to the depositional settings in the Bashkirian basin. The facies associations correspond to: distal middle ramp facies, open marine proximal middle ramp facies, high-energy innershoal facies, inner ramp facies of restricted lagoons, facies of affected by subaerial exposures. From west to east in the study the following trends in facies characterare identified: 1) a decrease open marine middle ramp facies and in the total thickness of the Bashkirian sections; 2) an increase in evidences of sub aerial exposures; 3) a decrease in the proportion of potential reservoir rocks. A general shallowing of the depositional setting was identified in an eastward direction, where potentially promising reservoir facies of shallow high-energy environments were replaced by facies of restricted lagoon and facies affected by subaerial exposures and meteoric diagenesis (palaeosols, dissolution). The applied approach based on detailed carbonate facies analysis allows predicting the distribution of potentially promising cross-sections within the region.

Two algorithms of few-view tomography are compared, specifically, the iterative Potts minimization algorithm (IPMA) and the algebraic reconstruction technique with TV-regularization and adaptive segmentation (ART-TVS). Both aim to reconstruct piecewise-constant structures, use the compressed sensing theory, and combine image reconstruction and segmentation procedures. Using a numerical experiment, it is shown that either algorithm can exactly reconstruct the Shepp-Logan phantom from as small as 7 views with noise characteristic of the medical applications of X-ray tomography. However, if an object has a complicated high-frequency structure (QR-code), the minimal number of views required for its exact reconstruction increases to 17–21 for ART-TVS and to 32–34 for IPMA. The ART-TVS algorithm developed by the authors is shown to outperform IPMA in reconstruction accuracy and speed and in resistance to abnormally high noise as well. ART-TVS holds good potential for further improvement.

In this study, Nd1.6Ca0.4Ni1−yCuyO4+δ-based electrode materials for intermediate temperature solid oxide fuel cells (IT-SOFCs) are investigated. Materials of the series (y = 0–0.4) are obtained by pyrolysis of glycerol-nitrate compositions. The study of crystal structure and high-temperature stability in air and under low oxygen partial pressure atmospheres are performed using high-resolution neutron and in situ X-ray powder diffraction. All the samples under the study assume a structure with Bmab sp.gr. below 350 °C and with I4/mmm sp.gr. above 500 °C. A transition in the volume thermal expansion coefficient values from 7.8–9.3 to 9.1–12.0 × 10−6, K−1 is observed at approximately 400 °C in air and 500 °C in helium.The oxygen self-diffusion coefficient values, obtained using isotope exchange, monotonically decrease with the Cu content increasing, while concentration dependence of the charge carriers goes through the maximum at x = 0.2. The Nd1.6Ca0.4Ni0.8Cu0.2O4+δ electrode materialdemonstrates chemical compatibility and superior electrochemical performance in the symmetrical cells with Ce0.8Sm0.2O1.9, BaCe0.8Sm0.2O3−δ, BaCe0.8Gd0.19Cu0.1O3−δ and BaCe0.5Zr0.3Y0.1Yb0.1O3−δ solid electrolytes, potentially for application in IT-SOFCs.

In the article, two main tasks of accounting are considered, which were formulated by Italian professor Vincenzo Giitti at the end of the nineteenth century, namely, the task of creating a scientifically sound accounting theory, and the task of developing accounting methods that meet the needs of modern enterprises. It is noted that at the present stage of development of accounting, these tasks have not lost their relevance. Despite all the attempts made, the generally recognized scientific theory of accounting has not yet been created, and the existing methods of accounting do not correspond to the needs of organizations created in the form of large integrated structures. The conducted research has shown that presently in the economy of the Russian Federation the significant share is occupied by the organizations carrying out financial and economic activity through affi ed and dependent societies. Organizations with a branched, integrated structure that includes subsidiaries and affiliates, as well as affiliated persons, account for at least 37% of the aggregate output of Russian organizations (total revenue of organizations) and a significant share of the capitalization of Russian organizations. The author argues that the existing consolidation methods provided for by international fi reporting standards are outside the accounting methodology, which, in turn, actualizes the problem of developing consolidated accounting methodology.

This work presents the results from a study of the structure and transport properties of Ca-doped La2NiO4+δ. La2−xCaxNiO4+δ (x = 0–0.4) materials that were synthesized via combustion of organic-nitrate precursors and characterized by X-ray diffraction (XRD), in situ XRD using synchrotron radiation, thermogravimetric analysis (TGA) and isotope exchange of oxygen with C18O2. The structure was defined as orthorhombic (Fmmm) for x = 0 and tetragonal (I4/mmm) for x = 0.1–0.4. Changes that occurred in the unit cell parameters and volume as the temperature changed during heating were shown to be caused by the excess oxygen loss. Typical for Ruddlesden–Popper phases, oxygen mobility and surface reactivity decreased as the Ca content was increased due to a reduction in the over-stoichiometric oxygen content with the exception of x = 0.1. This composition demonstrated its superior oxygen transport properties compared to La2NiO4+δ due to the enhanced oxygen mobility caused by structural features. Electrochemical data obtained showed relatively low polarization resistance for the electrodes with a low Ca content, which correlates well with oxygen transport properties.

This paper presents the study of electrophoretic deposition (EPD) of a proton-conducting electrolyte of BaCe0.89Gd0.1Cu0.01O3-δ (BCGCuO) on porous cathode substrates of LaNi0.6Fe0.4O3−δ (LNFO) and La1.7Ba0.3NiO4+δ (LBNO). EPD kinetics was studied in the process of deposition of both a LBNO sublayer on the porous LNFO substrate and a BCGCuO electrolyte layer. Addition of iodine was shown to significantly increase the deposited film weight and decrease the number of EPD cycles. During the deposition on the LNFO cathode, Ba preservation in the electrolyte layer after sintering at 1450 °C was achieved only with a film thickness greater than 20 μm. The presence of a thin LBNO sublayer (10 μm) did not have a pronounced effect on the preservation of Ba in the electrolyte layer. When using the bulk LBNO cathode substrate as a Ba source, Ba was retained in a nominal amount in the BCGCuO film with a thickness of 10 μm. The film obtained on the bulk LBNO substrate, being in composition close to the nominal composition of the BCGCuO electrolyte, possessed the highest electrical conductivity among the films deposited on the various cathode substrates. The technology developed is a base step in the adaptation of the EPD method for fabrication of cathode-supported Solid Oxide Fuel Cells (SOFCs) with dense barium-containing electrolyte films while maintaining their nominal composition and functional characteristics.