Izvestia Ufimskogo Nauchnogo Tsentra RAN最新文献

{"title":"ILGAMOV CRITERIA","authors":"S.F. Urmancheev","doi":"10.31040/2222-8349-2024-0-1-112-114","DOIUrl":"https://doi.org/10.31040/2222-8349-2024-0-1-112-114","url":null,"abstract":"No abstract required","PeriodicalId":507799,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140248513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"THE PROBLEM OF A NONLINEAR FILTRATION PRESSURE FIELD IN AN ENVIRONMENT WITH A WEAKLY COMPRESSIBLE SKELETON","authors":"A. I. Filippov, O. V. Akhmetova","doi":"10.31040/2222-8349-2024-0-1-72-78","DOIUrl":"https://doi.org/10.31040/2222-8349-2024-0-1-72-78","url":null,"abstract":"The solution of the problem of the pressure field during filtration of a compressible fluid in a porous medium with an incompressible skeleton in the presence of high-amplitude disturbances is presented. The equation describing pressure changes during field development takes into account the compressibility of the fluid and is presented in a nonlinear form. The known dependences of the density of the filtered medium on the pressure are approximated by a linear function. The movement is assumed to be one-dimensional and horizontal. The porosity, density and permeability of the porous medium skeleton, as well as the viscosity of the filtered medium are considered constant. The solution of the problem is found using an asymptotic expansion by a formal parameter added in the problem as a factor to the compressibility of the fluid. An approximate analytical solution of the nonlinear problem of the filtration pressure field in the zero and first approximations is found. The zero and first coefficients are represented by solutions of quasi-stationary equations, in which time is included as a parameter through the dimensions of the perturbation zone determined by the law of conservation of mass. It is established that taking into account the nonlinearity leads to a decrease in the size of the zone of disturbances of the pressure field. An approach to determining the upper boundary of the perturbation zone in nonlinear problems of this kind, which is based on the use of conservation laws, is proposed. It is shown that the special case of the zero approximation coincides with the solution of the linear problem obtained by the method of changing successive stationary states. The expressions found expand the possibilities of studying high-amplitude filtration processes, and the proposed approach removes the limitations of classical approaches associated with neglecting the dependence of fluid density on pressure in the divergent term of the continuity equation. The method used makes it possible to construct analytical expressions for decomposition coefficients orders of magnitude higher than the first, in addition, it creates the possibility of studying the contribution of nonlinearity caused by the dependence of permeability and viscosity on pressure.","PeriodicalId":507799,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140248590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"QUANTUM SIZE EFFECT IN CLEAN ALUMINUM FILMS","authors":"D.G. Bezymyannykh, N.G. Pugach, E. A. Sedov, K.Yu. Arutyunov, E. Ekomasov, B.G. Lvov","doi":"10.31040/2222-8349-2024-0-1-55-60","DOIUrl":"https://doi.org/10.31040/2222-8349-2024-0-1-55-60","url":null,"abstract":"In the modern world, there's a notable trend towards the active miniaturization of electronic devices. With technological advances enabling the manipulation of nanostructures, there's an increasing focus on exploring quantum effects pivotal to such designs. One distinguishing feature of nanostructures is the quantum nature of the electron's energy spectrum. This spectrum becomes discrete in directions where electrons move. Depending on the direction of this confinement, structures can be categorized as nanoplates, quantum wires, or quantum dots. The properties of such structures can significantly differ from those observed in large-scale systems. When discussing superconductivity, particular emphasis is placed on its macroscopic quantum properties.The influence on electronic wave functions is reflected in the characteristics of the superconducting state on broader scales. The Bardeen-Cooper-Schrieffer (BCS) theory is frequently utilized to analyze these nanostructures. The Gor’kov equations method serves as a potent tool for tasks related to the BCS theory. For instance, it can determine the parameters of the superconducting state, critical temperature, and current. Components of these equations, like Green's functions, are associated with various system properties. Research in the early stages of superconductivity studies revealed that the critical temperature (Tc ) – the temperature at which a material transitions to a superconducting state – can differ significantly between thin films and bulk materials. Intriguingly, reducing the film's thickness can both decrease (e.g., in niobium) and increase (e.g., in aluminum) the Tc value. This study delves into the quantum size effect in thin aluminum films, paving the way for materials with higher transition temperatures. Such advancements can simplify and make the maintenance of superconducting systems more cost-effective. In this study, a theoretical relationship between the critical temperature of a thin aluminum film and its thickness was derived. The Green's function method was chosen, which hadn't been previously employed for this computation. This approach offers greater potential compared to other superconductivity theory methods, presenting extensive avenues for theoretical exploration in this domain. The authors are confident that this work will contribute to further research on quantum dimensional effects in low-dimensional superconducting structures.","PeriodicalId":507799,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140249429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ELECTRICAL CONDUCTIVITY OF INDIUM–POLY(DIPHENYLENE PHTHALIDE)–INDIUM LAYERED STRUCTURES AT LOW TEMPERATURES","authors":"K.Yu. Arutyunov, Kh.T. Smaznova, V.V. Zavyalov, A. Yusupov, A. F. Galiev, A. N. Lachinov","doi":"10.31040/2222-8349-2024-0-1-79-84","DOIUrl":"https://doi.org/10.31040/2222-8349-2024-0-1-79-84","url":null,"abstract":"Poly(diphenylene phthalide) (PDP) is an organic polymer that is a dielectric in the ground state, but exhibits electrical conductivity in a metastable state, which can be stimulated by external disturbance. In this work, the transport properties of thin-film indium – PDP – indium “sandwiches” were experimentally studied over a wide temperature range. At temperatures below ~3.4 K, features are observed that can be explained by the effect of induced superconductivity in a thin film of conducting polymer sandwiched between two massive superconductors (indium).","PeriodicalId":507799,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140249153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"M.A. ILGAMOV – ORGANIZER AND EDITOR-IN-CHIEF","authors":"G. Khusainova","doi":"10.31040/2222-8349-2024-0-1-115-115","DOIUrl":"https://doi.org/10.31040/2222-8349-2024-0-1-115-115","url":null,"abstract":"No abstract required","PeriodicalId":507799,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140249575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TO THE 110TH ANNIVERSARY OF THE BIRTH YUSUPOV GARUN VALEEVICH","authors":"A. Akhatov","doi":"10.31040/2222-8349-2024-0-1-102-104","DOIUrl":"https://doi.org/10.31040/2222-8349-2024-0-1-102-104","url":null,"abstract":"No abstract required","PeriodicalId":507799,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140248973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"XTRACTS FROM DOCUMENTS AND LETTERS OF DIFFERENT YEARS","authors":"M. A. Ilgamov","doi":"10.31040/2222-8349-2024-0-1-116-118","DOIUrl":"https://doi.org/10.31040/2222-8349-2024-0-1-116-118","url":null,"abstract":"No abstract required","PeriodicalId":507799,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140249403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"MICROLENSING BY HARKO-KOVACS-LOBO PHANTOM WORMHOLE","authors":"G. Akhtaryanova, U.K. Khidirov, R.N. Izmailov","doi":"10.31040/2222-8349-2024-0-1-24-29","DOIUrl":"https://doi.org/10.31040/2222-8349-2024-0-1-24-29","url":null,"abstract":"This work investigates gravitational microlensing by a phantom wormhole. Gravitational microlensing is the effect of light bending in a gravitational field, in which one or more images of a light source appear and, in a particular case, an Einstein ring may appear. Gravity microlensing can be used as a possible observation method to detect or rule out the existence of wormholes. In this work, the Harko–Kovax–Lobo (HKL) wormhole will be examined as a lens. Using the lens equation and the definition of the Einstein radius, we find the angular positions of the physical image inside and outside the Einstein ring. The work contains a comparative analysis of the light curves of the Schwarzschild black hole and the HKL wormhole.","PeriodicalId":507799,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140248940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"INFLUENCE OF LECTIN Paenibacillus polymyxa 1460 (LII) ON LIPID SPECTRUM PROFILE OF MALE RATS UNDER IN ANTIBIOTIC-ASSOCIATED DYSBACTERIOSIS","authors":"L.V. Karpunina, M.V. Proskuryakova","doi":"10.31040/2222-8349-2024-0-1-91-95","DOIUrl":"https://doi.org/10.31040/2222-8349-2024-0-1-91-95","url":null,"abstract":"Paenibacillus polymyxa 1460 lectin (LII) isolated from the surface of soil nitrogen-fixing bacteria were shown to, contributes to the optimization of lipid metabolism in the organism of male albino rats with antibiotic-associated dysbacteriosis leading to the normal are important biochemical parameters in blood such as total cholesterol (TC), high density lipoproteins (HDL-C), low density lipoprotein (TC-LDL), lipoprotein very low density (XC-VLDL). The study of the effect of Paenibacillus polymyxa 1460 (LII) lectin on animal metabolism is important for understanding the mechanisms underlying the metabolic activity of these substances, and reveals the possibilities of its application in the practice of biomedical research with the prospect of its use as biologically active substances.","PeriodicalId":507799,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140250681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"IMPEDANCE ANALYSIS OF CHARGE TRANSFER PROCESSES IN A METAL/POLYMER/METAL STRUCTURE","authors":"M.S. Ishmukhametov, N.S. Bulankin, V.R. Karimov, A. F. Galiev","doi":"10.31040/2222-8349-2024-0-1-30-34","DOIUrl":"https://doi.org/10.31040/2222-8349-2024-0-1-30-34","url":null,"abstract":"The reaserch is devoted to the experimental study of charge transfer processes in thin films of an electroactive polymer from the class of polyarylene phthalides – poly (diphenylene phthalide). The method of impedance analysis of thin polymer films was used in this work. The material is quite well studied using other methods, such as thermally stimulated methods, optical spectroscopy, etc. However, frequency measurements were carried out mainly only in the field of determining capacitance-voltage characteristics. And since the polymer is electroactive, we should expect to identify features associated with charge transfer in the alternating field mode. In this regard, the work carried out an impedance analysis of thin films of poly (diphenylene phthalide) in the frequency range from 0.1 to 106 Hz. Typically, in impedance analysis, in addition to an ac field, a small DC bias voltage is applied to the metal/polymer/metal structure. This makes it possible to obtain data on surface polarization, charge carrier mobility, and the Maxwell-Wagner effect in the case of studying multilayer films. However, taking into account the electrical activity of the studied material, even impedance analysis in an alternating field, but with an effective voltage range from 0.1 to 10 V, made it possible to evaluate some of the electrophysical characteristics of the behavior of thin films. It was found that the slope of the impedance curve depends on the mechanism of transport of charge carriers in the polymer film. As the voltage increases from 0.1 to 10 V, an increase in the slope of the graph is observed. With an increase in the magnitude of the effective voltage, a transition occurs from the ohmic to the injection mechanism of transport of charge carriers limited by traps. When reaching 2 V, a mode of complete filling of the traps is observed, as a result of which an increase in voltage ceases to affect the slope of the frequency response. The dependence of the transition frequency fc on voltage has been plotted. This frequency corresponds to the transition from the predominance of the active to the reactive component of the impedance. Here, an exponential dependence on the magnitude of the applied voltage is observed, which also indicates the dependence of the mechanisms of transport of charge carriers in the polymer film on voltage (electric field).","PeriodicalId":507799,"journal":{"name":"Izvestia Ufimskogo Nauchnogo Tsentra RAN","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140249152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}