Pub Date : 2018-12-01DOI: 10.13189/UJPA.2018.120402
G. Kochemasov
As all cosmic bodies in Universe move in several orbits with very different orbiting frequencies they are affected by modulated waves. Very low orbiting frequencies of Galaxy and assemblies of galaxies in Universe modulate orbiting frequencies of smaller cosmic bodies with production of short, fine and finest radio and gamma rays. They appear as predicted by radio wave physics. The modulation is division and multiplication of the higher frequency by the lower one. As a result along with main frequencies appear two side frequencies with corresponding those tectonic granules. Examples are on surfaces of Saturn, Pluto, the Moon, Titan, Ceres, Phobos, Churyumov-Gerasimenko comet core. Lost mass and dark energy possibly are related to the shortest not yet measured oscillations.
{"title":"Modulated Wave Frequencies in the Solar System and Universe","authors":"G. Kochemasov","doi":"10.13189/UJPA.2018.120402","DOIUrl":"https://doi.org/10.13189/UJPA.2018.120402","url":null,"abstract":"As all cosmic bodies in Universe move in several orbits with very different orbiting frequencies they are affected by modulated waves. Very low orbiting frequencies of Galaxy and assemblies of galaxies in Universe modulate orbiting frequencies of smaller cosmic bodies with production of short, fine and finest radio and gamma rays. They appear as predicted by radio wave physics. The modulation is division and multiplication of the higher frequency by the lower one. As a result along with main frequencies appear two side frequencies with corresponding those tectonic granules. Examples are on surfaces of Saturn, Pluto, the Moon, Titan, Ceres, Phobos, Churyumov-Gerasimenko comet core. Lost mass and dark energy possibly are related to the shortest not yet measured oscillations.","PeriodicalId":23443,"journal":{"name":"Universal Journal of Physics and Application","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84196301","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 : 2018-12-01DOI: 10.13189/ujpa.2018.120403
M. Harland, Tim B Berberich, M. Katsnelson, A. Lichtenstein
We investigate the phenomenon of high-temperature superconductivity within a strong coupling perspective. The occurence is traced to a quantum critical point that is in the phase diagram of the plaquette's t; t0-Hubbard model. We develop a bottom-up approach combining several methods, i.e. exact diagonalization of an isolated plaquette, the Lanczos-method for a plaquette within a bath and cluster dynamical Mean-Field theory with continuous time quantum Monte-Carlo solver to embedd the plaquette in a lattice environment. The quantum critical point is located where the N = 2; 3; 4-sectors of the plaquette cross. This point is also found to show optimal doping. The wave order turns out to be largest at the localized-itinerant transition of the electrons. Furthermore, we present an explenation for the pseudo-gap phenomenon, that is explained by a soft mode related to local singlets of the plaquette. The theory presented here is similar to the resonating valence bond theory, but stresses the importance of local singlets.
{"title":"Plaquette Valence Bond Theory of Cuprate High-Temperature Superconductivity","authors":"M. Harland, Tim B Berberich, M. Katsnelson, A. Lichtenstein","doi":"10.13189/ujpa.2018.120403","DOIUrl":"https://doi.org/10.13189/ujpa.2018.120403","url":null,"abstract":"We investigate the phenomenon of high-temperature superconductivity within a strong coupling perspective. The occurence is traced to a quantum critical point that is in the phase diagram of the plaquette's t; t0-Hubbard model. We develop a bottom-up approach combining several methods, i.e. exact diagonalization of an isolated plaquette, the Lanczos-method for a plaquette within a bath and cluster dynamical Mean-Field theory with continuous time quantum Monte-Carlo solver to embedd the plaquette in a lattice environment. The quantum critical point is located where the N = 2; 3; 4-sectors of the plaquette cross. This point is also found to show optimal doping. The wave order turns out to be largest at the localized-itinerant transition of the electrons. Furthermore, we present an explenation for the pseudo-gap phenomenon, that is explained by a soft mode related to local singlets of the plaquette. The theory presented here is similar to the resonating valence bond theory, but stresses the importance of local singlets.","PeriodicalId":23443,"journal":{"name":"Universal Journal of Physics and Application","volume":"60 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83773452","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 : 2018-12-01DOI: 10.13189/UJPA.2018.120401
I. Asfour, D. Rached, S. Didier, A. soraya
The present work includes a first principle study of the electronic structure, elastic, magnetic and thermal properties of Co-based ternary full-Heusler alloys Co 2 C r X (x=Al,Ga). The lattice constant, bulk modulus, magnetic moment and density of states are studied using the full-potential linearized augmented plane wave method with the Generalized Gradient Approximation (GGA) as functional of exchange and correlation. This shows that the magnetic properties of the compound are dependent on electron concentration of main group element and all concentrations are magnetic in their equilibrium L2 1 structure. The calculations show that the alloys with all concentration are true half-metallic materials and exhibit 100% spin polarization at the Fermi level where it can be shifted within the energy-gap. In addition, the quasi-harmonic Debye model is applied to determine the thermal properties of the alloy.
本文主要研究了Co基三元全heusler合金Co 2 C r X (X =Al,Ga)的电子结构、弹性、磁性和热性能的第一性原理。采用广义梯度近似(GGA)作为交换和相关的泛函，利用全势线性化增广平面波方法研究了晶格常数、体模量、磁矩和态密度。这表明化合物的磁性与主族元素的电子浓度有关，所有浓度在其平衡L2 1结构中都具有磁性。计算表明，所有浓度的合金都是真正的半金属材料，并且在费米能级上表现出100%的自旋极化，可以在能隙内移动。此外，采用准谐波Debye模型确定了合金的热性能。
{"title":"Theoretical Study of the Electronic and Thermodynamic Properties of Co2CrZ (Z=Ga,Al)","authors":"I. Asfour, D. Rached, S. Didier, A. soraya","doi":"10.13189/UJPA.2018.120401","DOIUrl":"https://doi.org/10.13189/UJPA.2018.120401","url":null,"abstract":"The present work includes a first principle study of the electronic structure, elastic, magnetic and thermal properties of Co-based ternary full-Heusler alloys Co 2 C r X (x=Al,Ga). The lattice constant, bulk modulus, magnetic moment and density of states are studied using the full-potential linearized augmented plane wave method with the Generalized Gradient Approximation (GGA) as functional of exchange and correlation. This shows that the magnetic properties of the compound are dependent on electron concentration of main group element and all concentrations are magnetic in their equilibrium L2 1 structure. The calculations show that the alloys with all concentration are true half-metallic materials and exhibit 100% spin polarization at the Fermi level where it can be shifted within the energy-gap. In addition, the quasi-harmonic Debye model is applied to determine the thermal properties of the alloy.","PeriodicalId":23443,"journal":{"name":"Universal Journal of Physics and Application","volume":"2016 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86700034","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 : 2018-09-01DOI: 10.13189/ujpa.2018.120304
F. D’Auria, N. Debrecin, H. Glaeser
In the present paper a proposal is formulated to improve the safety of existing and future nuclear reactors. The idea is based upon the introduction of a new safety barrier against the release of radioactivity generated by the fission chain process. The proposal aims at fixing bases for possible strengthening of current Nuclear Reactor Safety by combining the logical frameworks associated with the concepts As-Low-As-Reasonably-Achievable (ALARA), Best-Estimate-Plus-Uncertainty (BEPU), Extended-Safety-Margin (E-SM), Independent-Assessment (IA) and Emergency-Rescue-Team (ERT). The expected impact of the new barrier upon selected nuclear accidents is outlined. The cost for the implementation of the additional barrier is expected to be affordable from a financial viewpoint and to contribute to restoring the public confidence towards nuclear technology.
{"title":"Introduction of an Additional Safety Barrier for Nuclear Power Reactors","authors":"F. D’Auria, N. Debrecin, H. Glaeser","doi":"10.13189/ujpa.2018.120304","DOIUrl":"https://doi.org/10.13189/ujpa.2018.120304","url":null,"abstract":"In the present paper a proposal is formulated to improve the safety of existing and future nuclear reactors. The idea is based upon the introduction of a new safety barrier against the release of radioactivity generated by the fission chain process. The proposal aims at fixing bases for possible strengthening of current Nuclear Reactor Safety by combining the logical frameworks associated with the concepts As-Low-As-Reasonably-Achievable (ALARA), Best-Estimate-Plus-Uncertainty (BEPU), Extended-Safety-Margin (E-SM), Independent-Assessment (IA) and Emergency-Rescue-Team (ERT). The expected impact of the new barrier upon selected nuclear accidents is outlined. The cost for the implementation of the additional barrier is expected to be affordable from a financial viewpoint and to contribute to restoring the public confidence towards nuclear technology.","PeriodicalId":23443,"journal":{"name":"Universal Journal of Physics and Application","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91372675","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 : 2018-09-01DOI: 10.13189/ujpa.2018.120301
William B. Maier II
{"title":"A New Approach to Classical Electrodynamics: Covariant Second-Order Field Variations","authors":"William B. Maier II","doi":"10.13189/ujpa.2018.120301","DOIUrl":"https://doi.org/10.13189/ujpa.2018.120301","url":null,"abstract":"","PeriodicalId":23443,"journal":{"name":"Universal Journal of Physics and Application","volume":"64 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73207446","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 : 2018-09-01DOI: 10.13189/ujpa.2018.120303
A. K. Kohli
The gamma irradiator technology has served the radiation processing industry very well. It has continued to progress despite number of challenges it has faced. Number of improvements in safety features helped it to quell the earlier challenges. Later 60 Co shortages and accelerator based X-ray systems becoming more competitive, considerably halted growth of gamma irradiators. But higher running expenditure, non-availability of appropriate irradiation volumes and reliable power supply at places particularly in rural areas did not make them as an automatic choice. The recent challenge due to heightened security concerns because of presence of intense 60 Co radioactive sources in gamma irradiators is quite daunting. Possibility of theft, or attack on gamma irradiator itself or transport container and high decommissioning costs for return of sources to the supplier for safe disposal is making it difficult for gamma irradiator technology to compete. Due to some inherent advantages, X-ray based technology has made the road ahead tough for gamma irradiator technology. However, X-ray system's lower efficiency of conversion of energy to electromagnetic radiation, its higher maintenance costs and its huge dependence on availability of economic and reliable power supply will eventually decide the time at which it replaces the gamma irradiator technology fully in any part of the world.
{"title":"Gamma Irradiator Technology: Challenges and Future Prospects","authors":"A. K. Kohli","doi":"10.13189/ujpa.2018.120303","DOIUrl":"https://doi.org/10.13189/ujpa.2018.120303","url":null,"abstract":"The gamma irradiator technology has served the radiation processing industry very well. It has continued to progress despite number of challenges it has faced. Number of improvements in safety features helped it to quell the earlier challenges. Later 60 Co shortages and accelerator based X-ray systems becoming more competitive, considerably halted growth of gamma irradiators. But higher running expenditure, non-availability of appropriate irradiation volumes and reliable power supply at places particularly in rural areas did not make them as an automatic choice. The recent challenge due to heightened security concerns because of presence of intense 60 Co radioactive sources in gamma irradiators is quite daunting. Possibility of theft, or attack on gamma irradiator itself or transport container and high decommissioning costs for return of sources to the supplier for safe disposal is making it difficult for gamma irradiator technology to compete. Due to some inherent advantages, X-ray based technology has made the road ahead tough for gamma irradiator technology. However, X-ray system's lower efficiency of conversion of energy to electromagnetic radiation, its higher maintenance costs and its huge dependence on availability of economic and reliable power supply will eventually decide the time at which it replaces the gamma irradiator technology fully in any part of the world.","PeriodicalId":23443,"journal":{"name":"Universal Journal of Physics and Application","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81649889","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 : 2018-06-01DOI: 10.13189/UJPA.2018.120202
A. Belyaev
Gas clouds in outer space always lose energy due to electromagnetic radiation, i.e., are non-isolated thermodynamic systems. Under certain conditions, the energy loss of the gas cloud can lead to replacement of the process of dispersion by the process of spontaneous gravitational compression. Under these conditions of the initiation process of spontaneous compression, the gravitational energy released by the compression of the cloud will correspond to losses due to electromagnetic radiation it experiences. Furthermore, the cloud will shrink with a decrease in internal energy with constant enthalpy. As a result, the process of spontaneous gravitational compression of a gas cloud in outer space will be accompanied by a decrease in the temperature of the cloud. This mechanism of compression of a gas cloud with simultaneous cooling could, at a certain stage of the evolution of the universe, govern one of the possible processes of formation of a hidden mass of galaxies.
{"title":"The Possibility of Spontaneous Gravitational Contraction of a Gas Cloud in Outer Space with Simultaneous Cooling of the Cloud","authors":"A. Belyaev","doi":"10.13189/UJPA.2018.120202","DOIUrl":"https://doi.org/10.13189/UJPA.2018.120202","url":null,"abstract":"Gas clouds in outer space always lose energy due to electromagnetic radiation, i.e., are non-isolated thermodynamic systems. Under certain conditions, the energy loss of the gas cloud can lead to replacement of the process of dispersion by the process of spontaneous gravitational compression. Under these conditions of the initiation process of spontaneous compression, the gravitational energy released by the compression of the cloud will correspond to losses due to electromagnetic radiation it experiences. Furthermore, the cloud will shrink with a decrease in internal energy with constant enthalpy. As a result, the process of spontaneous gravitational compression of a gas cloud in outer space will be accompanied by a decrease in the temperature of the cloud. This mechanism of compression of a gas cloud with simultaneous cooling could, at a certain stage of the evolution of the universe, govern one of the possible processes of formation of a hidden mass of galaxies.","PeriodicalId":23443,"journal":{"name":"Universal Journal of Physics and Application","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81921595","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 : 2018-04-01DOI: 10.13189/UJPA.2018.120102
Dessalegn Kenate, S. Shewamare, G. Melese
In this work we have studied the effect of interfacial layer on the refractive index, and propagation of waves in small spherical metal/dielectric composite separated by interfacial layers which is randomly embedded in a linear dielectric host matrix. The theoretical, and numerical descriptions are in terms of the interfacial factor (I) by incorporating Taylor expansion and Drude model. The result shows that both the interfacial layer property, and the percentage of the volume fraction of the metallic particles in the composite has an effect on the refractive index, and propagation of waves of the composite when the dielectric functions of the interfacial layer is more metal-like property than dielectric-like property.
{"title":"Effects of Interfacial Layer on Refractive Index and Propagation of Waves in Small Spherical Metal/ Dielectric Composite","authors":"Dessalegn Kenate, S. Shewamare, G. Melese","doi":"10.13189/UJPA.2018.120102","DOIUrl":"https://doi.org/10.13189/UJPA.2018.120102","url":null,"abstract":"In this work we have studied the effect of interfacial layer on the refractive index, and propagation of waves in small spherical metal/dielectric composite separated by interfacial layers which is randomly embedded in a linear dielectric host matrix. The theoretical, and numerical descriptions are in terms of the interfacial factor (I) by incorporating Taylor expansion and Drude model. The result shows that both the interfacial layer property, and the percentage of the volume fraction of the metallic particles in the composite has an effect on the refractive index, and propagation of waves of the composite when the dielectric functions of the interfacial layer is more metal-like property than dielectric-like property.","PeriodicalId":23443,"journal":{"name":"Universal Journal of Physics and Application","volume":"1 1","pages":"11-17"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90068017","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 : 2018-04-01DOI: 10.13189/ujpa.2018.120101
C. Opara, O. Adizua, J. Ebeniro
Seismic refraction was used to image the near-surface, using a3D seismic data acquired from an onshore Niger Delta field. The objective of the study was to build a near-surface model of the earth in terms of sub-weathering layer thicknesses and seismic wave velocities and highlight the near-surface seismic wave velocity variation in the region. A velocity-depth model consisting of the weathering layer and three consolidated (sub-weathering) layers was first estimated. The first-breaks were picked and used as input for this study. The models were generally consistent in terms of their large-scale features, demonstrating the robustness of refraction data inversion in general. Results support confidence in the reliability and robustness of the refraction inversion method. The method of analysis and resolution for 3-layer models adopted in this study may be used in resolving such cases observed during processing of seismic reflection data from the Niger-Delta Basin.
{"title":"Near-surface Seismic Velocity Model Building from First Arrival Travel-times - A Case Study from an Onshore, Niger Delta Field","authors":"C. Opara, O. Adizua, J. Ebeniro","doi":"10.13189/ujpa.2018.120101","DOIUrl":"https://doi.org/10.13189/ujpa.2018.120101","url":null,"abstract":"Seismic refraction was used to image the near-surface, using a3D seismic data acquired from an onshore Niger Delta field. The objective of the study was to build a near-surface model of the earth in terms of sub-weathering layer thicknesses and seismic wave velocities and highlight the near-surface seismic wave velocity variation in the region. A velocity-depth model consisting of the weathering layer and three consolidated (sub-weathering) layers was first estimated. The first-breaks were picked and used as input for this study. The models were generally consistent in terms of their large-scale features, demonstrating the robustness of refraction data inversion in general. Results support confidence in the reliability and robustness of the refraction inversion method. The method of analysis and resolution for 3-layer models adopted in this study may be used in resolving such cases observed during processing of seismic reflection data from the Niger-Delta Basin.","PeriodicalId":23443,"journal":{"name":"Universal Journal of Physics and Application","volume":"104 1","pages":"1-10"},"PeriodicalIF":0.0,"publicationDate":"2018-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89004867","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 : 2017-12-01DOI: 10.13189/UJPA.2017.110605
A. Belyaev
In this paper, it examines the trends of stellar evolution reflected in modern physics, identifying the uncertainties present in the established schemes. It explains that during spontaneous contraction of gas clouds the process of heating up cannot be replaced by cooling without qualitative changes in the structure of the clouds. It is shown that the luminous objects can be resistant to decay due to the gravitational interactions, even at low mass; that the outcome of stellar evolution does not yet have a clear description; that spontaneous gravitational contraction of gas clouds in space is largely concluded by the formation of structures resistant to gravitational forces. The recognition of structures resistant to the forces of gravity is a very important element of understanding, which will help in future theoretical research.
{"title":"Trends of Stellar Evolution in Modern Physics","authors":"A. Belyaev","doi":"10.13189/UJPA.2017.110605","DOIUrl":"https://doi.org/10.13189/UJPA.2017.110605","url":null,"abstract":"In this paper, it examines the trends of stellar evolution reflected in modern physics, identifying the uncertainties present in the established schemes. It explains that during spontaneous contraction of gas clouds the process of heating up cannot be replaced by cooling without qualitative changes in the structure of the clouds. It is shown that the luminous objects can be resistant to decay due to the gravitational interactions, even at low mass; that the outcome of stellar evolution does not yet have a clear description; that spontaneous gravitational contraction of gas clouds in space is largely concluded by the formation of structures resistant to gravitational forces. The recognition of structures resistant to the forces of gravity is a very important element of understanding, which will help in future theoretical research.","PeriodicalId":23443,"journal":{"name":"Universal Journal of Physics and Application","volume":"77 1","pages":"247-263"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87065127","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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