Pub Date : 2024-03-12DOI: 10.31040/2222-8349-2024-0-1-72-78
A. I. Filippov, O. V. Akhmetova
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.
{"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}
Pub Date : 2024-03-12DOI: 10.31040/2222-8349-2024-0-1-55-60
D.G. Bezymyannykh, N.G. Pugach, E. A. Sedov, K.Yu. Arutyunov, E. Ekomasov, B.G. Lvov
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.
{"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}
Pub Date : 2024-03-12DOI: 10.31040/2222-8349-2024-0-1-79-84
K.Yu. Arutyunov, Kh.T. Smaznova, V.V. Zavyalov, A. Yusupov, A. F. Galiev, A. N. Lachinov
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).
聚（邻苯二甲酸二苯酯）（PDP）是一种有机聚合物，它在基态时是一种电介质，但在可受外部干扰刺激的稳定状态下具有导电性。在这项研究中，我们对薄膜铟-PDP-铟 "三明治 "的传输特性进行了宽温度范围的实验研究。在 ~3.4 K 以下的温度下，观察到的特征可以用夹在两个大质量超导体（铟）之间的导电聚合物薄膜的诱导超导效应来解释。
{"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}
Pub Date : 2024-03-12DOI: 10.31040/2222-8349-2024-0-1-116-118
M. A. Ilgamov
No abstract required
无需摘要
{"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}
Pub Date : 2024-03-12DOI: 10.31040/2222-8349-2024-0-1-24-29
G. Akhtaryanova, U.K. Khidirov, R.N. Izmailov
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.
{"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}
Pub Date : 2024-03-12DOI: 10.31040/2222-8349-2024-0-1-91-95
L.V. Karpunina, M.V. Proskuryakova
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.
{"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}
Pub Date : 2024-03-12DOI: 10.31040/2222-8349-2024-0-1-30-34
M.S. Ishmukhametov, N.S. Bulankin, V.R. Karimov, A. F. Galiev
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).
该研究致力于对聚芳基酞酸酯--聚（二苯基酞酸酯）类电活性聚合物薄膜中的电荷转移过程进行实验研究。这项研究采用了聚合物薄膜阻抗分析方法。使用其他方法，如热刺激法、光学光谱法等，对这种材料进行了很好的研究。然而，频率测量主要是在确定电容-电压特性的领域进行的。既然聚合物具有电活性，我们就应该期望找出与交变场模式下电荷转移有关的特征。在这方面，这项研究在 0.1 至 106 Hz 的频率范围内对聚（二苯基酞）薄膜进行了阻抗分析。通常情况下，在阻抗分析中，除了交流场外，还要在金属/聚合物/金属结构上施加一个小的直流偏置电压。这样，在研究多层薄膜时，就可以获得有关表面极化、电荷载流子迁移率和麦克斯韦尔-瓦格纳效应的数据。不过，考虑到所研究材料的电活动，即使在交变电场中进行阻抗分析，但有效电压范围为 0.1 至 10 V，也能评估薄膜行为的一些电物理特性。研究发现，阻抗曲线的斜率取决于电荷载体在聚合物薄膜中的传输机制。当电压从 0.1 V 增加到 10 V 时，可以观察到曲线斜率的增加。随着有效电压幅度的增加，电荷载流子的传输机制从欧姆模式过渡到受陷阱限制的注入模式。当电压达到 2 V 时，观察到陷阱完全充满的模式，因此电压的增加不再影响频率响应的斜率。我们绘制了过渡频率 fc 与电压的关系曲线。该频率对应于阻抗从有源分量占主导地位向无源分量占主导地位的过渡。在这里，可以观察到外加电压的指数依赖性，这也表明电荷载流子在聚合物薄膜中的传输机制取决于电压（电场）。
{"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}
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