Pub Date : 2023-02-01DOI: 10.37538/0039-2383.2023.1.7.14
M. Sukhoterin, L. N. Kondratjeva, I. Voytko, E. M. Pastushok
To find the natural frequencies of antisymmetric oscillation patterns of a rectangular plate, two opposite sides of which are pinched and the other two are free (CFCF plate), a method of sorting frequency values («shooting method») in combination with the method of successive approximations is proposed. The deflection function is represented by two hyperbola-trigonometric series along two coordinates. When all the conditions of the boundary value problem are met, a homogeneous infinite system of linear algebraic equations is obtained with respect to the indeterminate coefficients of these series, which contains the oscillation frequency as a parameter. To find nontrivial solutions of the corresponding reduced system, an iterative process of parameter iteration is organized. Numerical results are obtained for the first two antisymmetric eigenforms. The influence of the number of series terms and the number of iterations on the accuracy of the results is investigated. A comparison with the results of other authors and experimental data is given.
{"title":"DETERMINATION OF THE FREQUENCY OF ANTISYMMETRIC FORMS OF FREE OSCILLATIONS OF A RECTANGULAR CFCF – PLATE","authors":"M. Sukhoterin, L. N. Kondratjeva, I. Voytko, E. M. Pastushok","doi":"10.37538/0039-2383.2023.1.7.14","DOIUrl":"https://doi.org/10.37538/0039-2383.2023.1.7.14","url":null,"abstract":"To find the natural frequencies of antisymmetric oscillation patterns of a rectangular plate, two opposite sides of which are pinched and the other two are free (CFCF plate), a method of sorting frequency values («shooting method») in combination with the method of successive approximations is proposed. The deflection function is represented by two hyperbola-trigonometric series along two coordinates. When all the conditions of the boundary value problem are met, a homogeneous infinite system of linear algebraic equations is obtained with respect to the indeterminate coefficients of these series, which contains the oscillation frequency as a parameter. To find nontrivial solutions of the corresponding reduced system, an iterative process of parameter iteration is organized. Numerical results are obtained for the first two antisymmetric eigenforms. The influence of the number of series terms and the number of iterations on the accuracy of the results is investigated. A comparison with the results of other authors and experimental data is given.","PeriodicalId":273885,"journal":{"name":"STRUCTURAL MECHANICS AND ANALYSIS OF CONSTRUCTIONS","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130614994","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 : 2022-08-28DOI: 10.37538/0039-2383.2022.4.36.42
E. Popov, V. V. Sopilov, B. Labudin, A.E. Zemcovskii, E.S. Tochilova
The mathematical model for the calculation of component elements with non-linear-flexible shear connections by deformations is presented. The algorithm is based on the theory of calculation of component rods by A. R. Rzhanitsyn, however, the rigidity of the shear connections is refined at each step for each connection, depending on shear force. It has been established that neglecting the actual nature of the connections deformation introduces a significant error in the assessment of the deformability of component beams with mechanical connections.
建立了非线性柔性剪切连接构件的变形计算数学模型。该算法基于A. R. Rzhanitsyn的构件杆计算理论，但根据剪力的不同，在每个连接的每一步都细化了剪切连接的刚度。研究表明，忽略连接变形的实际性质会导致对具有机械连接的构件梁的变形能力的评估出现重大误差。
{"title":"Calculation of Composite Bending Wooden Elements by Deformations Considering the Nonlinear Work of Shear Bonds","authors":"E. Popov, V. V. Sopilov, B. Labudin, A.E. Zemcovskii, E.S. Tochilova","doi":"10.37538/0039-2383.2022.4.36.42","DOIUrl":"https://doi.org/10.37538/0039-2383.2022.4.36.42","url":null,"abstract":"The mathematical model for the calculation of component elements with non-linear-flexible shear connections by deformations is presented. The algorithm is based on the theory of calculation of component rods by A. R. Rzhanitsyn, however, the rigidity of the shear connections is refined at each step for each connection, depending on shear force. It has been established that neglecting the actual nature of the connections deformation introduces a significant error in the assessment of the deformability of component beams with mechanical connections.","PeriodicalId":273885,"journal":{"name":"STRUCTURAL MECHANICS AND ANALYSIS OF CONSTRUCTIONS","volume":"120 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123238104","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 : 2022-08-28DOI: 10.37538/0039-2383.2022.4.29.35
T. Mukhamediev, S. Maiorov
The results of study of influence compressed fiber reinforced polymer bars on the capacity of eccentrically compressed elements are presented. The recommendations to assignment of yield strength for compressed fiber reinforced polymer bars are given. The dependence for strength calculation elements taking account the operation of compressed fiber reinforced polymer bars are suggest. The results of reliability verification of proposed method for calculating eccentrically compressed elements with experimental data are presented.
{"title":"Strength calculation of eccentrically compressed elements taking into account the operation of compressed fiber reinforced polymer bars","authors":"T. Mukhamediev, S. Maiorov","doi":"10.37538/0039-2383.2022.4.29.35","DOIUrl":"https://doi.org/10.37538/0039-2383.2022.4.29.35","url":null,"abstract":"The results of study of influence compressed fiber reinforced polymer bars on the capacity of eccentrically compressed elements are presented. The recommendations to assignment of yield strength for compressed fiber reinforced polymer bars are given. The dependence for strength calculation elements taking account the operation of compressed fiber reinforced polymer bars are suggest. The results of reliability verification of proposed method for calculating eccentrically compressed elements with experimental data are presented.","PeriodicalId":273885,"journal":{"name":"STRUCTURAL MECHANICS AND ANALYSIS OF CONSTRUCTIONS","volume":"190 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132681394","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 : 2022-08-28DOI: 10.37538/0039-2383.2022.4.43.49
G. Manuylov, S. B. Kositsyn, M. Begichev
When solving frame stability problems, replacing a distributed load acting on a frame element with an equivalent load in the form of concentrated forces that are applied in the frame nodes is often resorted to. This causes the bending equilibrium of the beam to become a non-bending tension-compression equilibrium. The buckling load for such frames can be either greater or less than the actual load.
{"title":"Problems of replacing nonbifurcational stability problems of elastic frames with bifurcational problems","authors":"G. Manuylov, S. B. Kositsyn, M. Begichev","doi":"10.37538/0039-2383.2022.4.43.49","DOIUrl":"https://doi.org/10.37538/0039-2383.2022.4.43.49","url":null,"abstract":"When solving frame stability problems, replacing a distributed load acting on a frame element with an equivalent load in the form of concentrated forces that are applied in the frame nodes is often resorted to. This causes the bending equilibrium of the beam to become a non-bending tension-compression equilibrium. The buckling load for such frames can be either greater or less than the actual load.","PeriodicalId":273885,"journal":{"name":"STRUCTURAL MECHANICS AND ANALYSIS OF CONSTRUCTIONS","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127531679","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 : 2022-08-28DOI: 10.37538/0039-2383.2022.4.50.54
A. Minasyan
The issues of general and local stability of multi-storey buildings and high-rise structures under emergency (explosions, earthquakes) loads are considered. Differential equations describing three-dimensional translational and three-dimensional rotational oscillations are given. Dependences of local and general stability estimation are obtained. A numerical example is given that takes into account local stability in higher forms of oscillation. At the same time, the behavior of a real 16-storey frame building in Leninakan during the earthquake in Spitak on December 7, 1988 is analyzed. The main causes of loss of stability and destruction are carried out.
{"title":"General and local stability of multi-storey buildings under dynamic and seismic influences","authors":"A. Minasyan","doi":"10.37538/0039-2383.2022.4.50.54","DOIUrl":"https://doi.org/10.37538/0039-2383.2022.4.50.54","url":null,"abstract":"The issues of general and local stability of multi-storey buildings and high-rise structures under emergency (explosions, earthquakes) loads are considered. Differential equations describing three-dimensional translational and three-dimensional rotational oscillations are given. Dependences of local and general stability estimation are obtained. A numerical example is given that takes into account local stability in higher forms of oscillation. At the same time, the behavior of a real 16-storey frame building in Leninakan during the earthquake in Spitak on December 7, 1988 is analyzed. The main causes of loss of stability and destruction are carried out.","PeriodicalId":273885,"journal":{"name":"STRUCTURAL MECHANICS AND ANALYSIS OF CONSTRUCTIONS","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116691831","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 : 2022-08-28DOI: 10.37538/0039-2383.2022.4.68.78
M. Farfel, L. S. Rozhkova
Before the reconstruction and restoration of the Eastern Wing of the General Staff, in order to install an atrium in the courtyard 4 for the premises of the State Hermitage Museum in St. Petersburg, the V.A. Kucherenko TSNIISK of JSC “SIC “Construction” tested a full-scale glass beam intended as a covering run. The article presents the test procedure, the design of the test stand, devices for applying the load and taking readings from the instruments. An analysis of the results of the experiment is presented, on the basis of which, instead of the proposed glass beams, metal beams and girders were installed on the courtyard covering. Recommendations are given for the use of glass beams as load-bearing structures.
{"title":"Testing of glass beams intended for coating runs atrium in St. Petersburg","authors":"M. Farfel, L. S. Rozhkova","doi":"10.37538/0039-2383.2022.4.68.78","DOIUrl":"https://doi.org/10.37538/0039-2383.2022.4.68.78","url":null,"abstract":"Before the reconstruction and restoration of the Eastern Wing of the General Staff, in order to install an atrium in the courtyard 4 for the premises of the State Hermitage Museum in St. Petersburg, the V.A. Kucherenko TSNIISK of JSC “SIC “Construction” tested a full-scale glass beam intended as a covering run. The article presents the test procedure, the design of the test stand, devices for applying the load and taking readings from the instruments. An analysis of the results of the experiment is presented, on the basis of which, instead of the proposed glass beams, metal beams and girders were installed on the courtyard covering. Recommendations are given for the use of glass beams as load-bearing structures.","PeriodicalId":273885,"journal":{"name":"STRUCTURAL MECHANICS AND ANALYSIS OF CONSTRUCTIONS","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123506782","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 : 2022-08-28DOI: 10.37538/0039-2383.2022.4.61.67
A. Kovalenko, D.V. Konin, P.V. Nahvalnov, D. Solovev
In order to confirm the slip factor, a series of experiments carried out on models of slip critical joints with contact surfaces subjected to shot blasting. The dependence of the slip factor on the technology of preparation of contact surfaces and the presence of a protective coating is established. The data obtained suggest that achieving the maximum guaranteed coefficient of friction of 0.58 requires careful control over the preparation of the contact surface. The absence of regulatory requirements for the technology of abrasive blasting and quality control of the friction surface is noted. Differences in approaches to the determination of the coefficient of friction between domestic and foreign methods are given. The expediency of revising the values of slip factor for various methods of surface treatment adopted in SP 16.13330.2017 for slip critical joints is substantiated.
{"title":"Experimental study of the coefficient of friction in slip critical bolt joints","authors":"A. Kovalenko, D.V. Konin, P.V. Nahvalnov, D. Solovev","doi":"10.37538/0039-2383.2022.4.61.67","DOIUrl":"https://doi.org/10.37538/0039-2383.2022.4.61.67","url":null,"abstract":"In order to confirm the slip factor, a series of experiments carried out on models of slip critical joints with contact surfaces subjected to shot blasting. The dependence of the slip factor on the technology of preparation of contact surfaces and the presence of a protective coating is established. The data obtained suggest that achieving the maximum guaranteed coefficient of friction of 0.58 requires careful control over the preparation of the contact surface. The absence of regulatory requirements for the technology of abrasive blasting and quality control of the friction surface is noted. Differences in approaches to the determination of the coefficient of friction between domestic and foreign methods are given. The expediency of revising the values of slip factor for various methods of surface treatment adopted in SP 16.13330.2017 for slip critical joints is substantiated.","PeriodicalId":273885,"journal":{"name":"STRUCTURAL MECHANICS AND ANALYSIS OF CONSTRUCTIONS","volume":"221 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123360284","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 : 2022-08-28DOI: 10.37538/0039-2383.2022.4.55.60
V. Utkin, Zh.V. Kosheleva, L. A. Sushev
The article considers the calculation of the effective length of an under-ream bored pile and a pile without broadening. The pile is located under axial compression conditions in a homogeneous ground of the base. Reducing the cost of piles is an important problem, since the manufacture of piles with broadening is characterized by increased cost. This can be achieved by identifying the value of the effective pile length. The length of the pile is considered effective if a stress in the ground is reached under its widened part equal to the calculated value R of the resistance of the ground of the base. The values of soil resistance are given in SP 24.13330.2011 (2021) for different soils at different depths of immersion of the Hc pile. In the paper, the tabular values of H and R are presented as a dependence of R on Hc (functions). The type of these functions is determined by the least squares method. In contrast to the instructions for the calculations of piles according to JV 24.13330.2011 (2021), a different design scheme for the operation of the pile in the ground of the base is proposed without bringing it to a “breakdown”. As a result, a calculation equation is presented to determine the effective length of the under-ream bored pile. Similar calculations are applicable for piles without broadening.
{"title":"Calculation of the effective length of hanging under-ream bored piles under compressive load in a homogeneous ground of the base","authors":"V. Utkin, Zh.V. Kosheleva, L. A. Sushev","doi":"10.37538/0039-2383.2022.4.55.60","DOIUrl":"https://doi.org/10.37538/0039-2383.2022.4.55.60","url":null,"abstract":"The article considers the calculation of the effective length of an under-ream bored pile and a pile without broadening. The pile is located under axial compression conditions in a homogeneous ground of the base. Reducing the cost of piles is an important problem, since the manufacture of piles with broadening is characterized by increased cost. This can be achieved by identifying the value of the effective pile length. The length of the pile is considered effective if a stress in the ground is reached under its widened part equal to the calculated value R of the resistance of the ground of the base. The values of soil resistance are given in SP 24.13330.2011 (2021) for different soils at different depths of immersion of the Hc pile. In the paper, the tabular values of H and R are presented as a dependence of R on Hc (functions). The type of these functions is determined by the least squares method. In contrast to the instructions for the calculations of piles according to JV 24.13330.2011 (2021), a different design scheme for the operation of the pile in the ground of the base is proposed without bringing it to a “breakdown”. As a result, a calculation equation is presented to determine the effective length of the under-ream bored pile. Similar calculations are applicable for piles without broadening.","PeriodicalId":273885,"journal":{"name":"STRUCTURAL MECHANICS AND ANALYSIS OF CONSTRUCTIONS","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132392806","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 : 2022-08-28DOI: 10.37538/0039-2383.2022.4.2.7
P. Alekseev, A. Trofimov
Currently beam vaulted floors of brick are not designed, but most of the existing buildings with this type of ceiling need to be reconstructed. Designers are faced with the problem of the lack of a normative method for calculating vaulted ceilings, which would take into account the composite action of beams with vaulted filling. In this regard, in order to determine the category of the technical condition of the ceilings, the checking calculation is made for a hinged metal beam with uniformly distributed load, which underrates the bearing capacity of the floor. In accordance with the results of an incorrect checking calculation for vaulted ceilings with metal beams, the technical condition category is reduced, which leads to unjustified strengthening of the ceiling or its dismantling. In this article, we developed the calculation method that takes into account the composite action of structural elements.
{"title":"Calculation vaulted floors of brick on metal beams «Sectors of the thick-walled ring» method","authors":"P. Alekseev, A. Trofimov","doi":"10.37538/0039-2383.2022.4.2.7","DOIUrl":"https://doi.org/10.37538/0039-2383.2022.4.2.7","url":null,"abstract":"Currently beam vaulted floors of brick are not designed, but most of the existing buildings with this type of ceiling need to be reconstructed. Designers are faced with the problem of the lack of a normative method for calculating vaulted ceilings, which would take into account the composite action of beams with vaulted filling. In this regard, in order to determine the category of the technical condition of the ceilings, the checking calculation is made for a hinged metal beam with uniformly distributed load, which underrates the bearing capacity of the floor. In accordance with the results of an incorrect checking calculation for vaulted ceilings with metal beams, the technical condition category is reduced, which leads to unjustified strengthening of the ceiling or its dismantling. In this article, we developed the calculation method that takes into account the composite action of structural elements.","PeriodicalId":273885,"journal":{"name":"STRUCTURAL MECHANICS AND ANALYSIS OF CONSTRUCTIONS","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129610852","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 : 2022-08-28DOI: 10.37538/0039-2383.2022.4.8.23
S. V. Bakushev
We consider the construction of coefficients of equilibrium differential equations in displacements for a three-dimensional physically and geometrically nonlinear theory of elasticity. Differential equations of equilibrium are done in a rectangular Cartesian coordinate system. Closing equations are variable modules of volumetric and shear deformation; physical relations are approximated by bilinear functions. Physical dependencies are recorded for four possible rules of continuum deformation in accordance with bilinear graphs of volume and shear deformation. The rules of deformation on each linear section of bilinear diagrams of volumetric and shear deformation are determined by the secant modules of bilinear graphs of volumetric and shear deformation diagrams. The analysis shows that the coefficients of differential equations of equilibrium in displacements, which are second-order partial differential equations of displacements along spatial coordinates, are quadratic functions of the first derivatives of displacements along spatial coordinates. The constructed three-dimensional differential equations of equilibrium in displacements can be applied in the calculation of structures using three-dimensional equilibrium equations of physically and geometrically nonlinear theory of elasticity in displacements, the closing equations of physical relations for which are approximated by bilinear functions.
{"title":"Displacement differential equations of equilibrium in three-dimensional geometrically and physically nonlinear theory of elasticity for discontinuous closing equations in the cartesian coordinate system","authors":"S. V. Bakushev","doi":"10.37538/0039-2383.2022.4.8.23","DOIUrl":"https://doi.org/10.37538/0039-2383.2022.4.8.23","url":null,"abstract":"We consider the construction of coefficients of equilibrium differential equations in displacements for a three-dimensional physically and geometrically nonlinear theory of elasticity. Differential equations of equilibrium are done in a rectangular Cartesian coordinate system. Closing equations are variable modules of volumetric and shear deformation; physical relations are approximated by bilinear functions. Physical dependencies are recorded for four possible rules of continuum deformation in accordance with bilinear graphs of volume and shear deformation. The rules of deformation on each linear section of bilinear diagrams of volumetric and shear deformation are determined by the secant modules of bilinear graphs of volumetric and shear deformation diagrams. The analysis shows that the coefficients of differential equations of equilibrium in displacements, which are second-order partial differential equations of displacements along spatial coordinates, are quadratic functions of the first derivatives of displacements along spatial coordinates. The constructed three-dimensional differential equations of equilibrium in displacements can be applied in the calculation of structures using three-dimensional equilibrium equations of physically and geometrically nonlinear theory of elasticity in displacements, the closing equations of physical relations for which are approximated by bilinear functions.","PeriodicalId":273885,"journal":{"name":"STRUCTURAL MECHANICS AND ANALYSIS OF CONSTRUCTIONS","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114358512","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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