Pub Date : 2009-10-30DOI: 10.1109/ASEMD.2009.5306677
Yongjun Huang, G. Wen, Tianqian Li, K. Xie
The tunneling effect in a left handed metamaterial (LHM) consisting of ferrites and wire array is presented. The ferrites based LHM exhibits a near perfect transmission with very low losses and reflections due to the ε = − ε0 and μ = − μ0. Based on the theoretical results of effective permeability and permittivity of the LHM, the parameter conditions of perfect tunneling effect through a LHM slab is analyzed. Numerically simulated results indicated that the tunneling effect can be found in the microwave frequencies and demonstrated aforementioned theoretical results very well.
{"title":"Tunneling effect in ferrites based left handed metamaterial","authors":"Yongjun Huang, G. Wen, Tianqian Li, K. Xie","doi":"10.1109/ASEMD.2009.5306677","DOIUrl":"https://doi.org/10.1109/ASEMD.2009.5306677","url":null,"abstract":"The tunneling effect in a left handed metamaterial (LHM) consisting of ferrites and wire array is presented. The ferrites based LHM exhibits a near perfect transmission with very low losses and reflections due to the ε = − ε<inf>0</inf> and μ = − μ<inf>0</inf>. Based on the theoretical results of effective permeability and permittivity of the LHM, the parameter conditions of perfect tunneling effect through a LHM slab is analyzed. Numerically simulated results indicated that the tunneling effect can be found in the microwave frequencies and demonstrated aforementioned theoretical results very well.","PeriodicalId":354649,"journal":{"name":"2009 International Conference on Applied Superconductivity and Electromagnetic Devices","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120972603","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 : 2009-10-30DOI: 10.1109/ASEMD.2009.5306634
Shi Jin, Fengge Zhang, Xiuping Wang
Based on speed sensorless technology, a direct torque control strategy suitable for variable speed constant frequency brushless doubly-fed wind power generator is proposed in this paper. An advanced flux observation method is presented to avoid flux drift phenomenon. Furthermore, the synchronous rotating speed and slip speed are estimated by observing the rotor flux to obtain the generator speed, and further to implement speed sensorless control. Simulations show that the proposed observation method can enhance flux and speed observation precision, and greatly improve low speed performance of speed sensorless direct torque control system, which is helpful to the direct-drive type development of brushless doubly-fed wind power generation system and to the utilization of low speed wind power.
{"title":"Speed sensorless direct torque control of brushless doubly-fed generator for wind power generation","authors":"Shi Jin, Fengge Zhang, Xiuping Wang","doi":"10.1109/ASEMD.2009.5306634","DOIUrl":"https://doi.org/10.1109/ASEMD.2009.5306634","url":null,"abstract":"Based on speed sensorless technology, a direct torque control strategy suitable for variable speed constant frequency brushless doubly-fed wind power generator is proposed in this paper. An advanced flux observation method is presented to avoid flux drift phenomenon. Furthermore, the synchronous rotating speed and slip speed are estimated by observing the rotor flux to obtain the generator speed, and further to implement speed sensorless control. Simulations show that the proposed observation method can enhance flux and speed observation precision, and greatly improve low speed performance of speed sensorless direct torque control system, which is helpful to the direct-drive type development of brushless doubly-fed wind power generation system and to the utilization of low speed wind power.","PeriodicalId":354649,"journal":{"name":"2009 International Conference on Applied Superconductivity and Electromagnetic Devices","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125096426","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 : 2009-10-30DOI: 10.1109/ASEMD.2009.5306612
Y. Xin, H. Hui, W. Gong, F. Ye, J. Z. Wang, B. Tian, A. Ren, M. Zi
We have undertaken research and development of superconducting cables and superconducting fault current limiters and have made significant progress in the last six years. At Puji Substation of Southern China Power Grid, a 35 kV superconducting cable system was installed and energized in 2004. In 2007, a 35 kV superconducting fault current limiter (FCL) was installed in the substation. After field tests and trial operation, this device was commissioned to live-grid operation in 2008. As of now, Puji Substation is the only substation in the world that has both superconducting cable and superconducting FCL operating in its network. The cable system consists of three 33.5 m warm dielectric superconducting cables, six terminations, and a closed cycle liquid nitrogen cooling station. Up to date, it has delivered more than 400,000,000kW·h of electricity to the customers, including 4 factories and a residential population of about 100,000. The FCL is a saturated magnetic type superconducting fault current limiter. Its performance has been tested under live-grid operation conditions. The testing results show that the FCL has low impedance at normal power transmission and reliable fault current limiting capability in a short-circuit situation. These results are in good agreement with the design expectations. Technical details of the installation, operation and some testing data for the cable and fault current limiter are reported in this article.
{"title":"Superconducting cable and superconducting fault current limiter at Puji Substation","authors":"Y. Xin, H. Hui, W. Gong, F. Ye, J. Z. Wang, B. Tian, A. Ren, M. Zi","doi":"10.1109/ASEMD.2009.5306612","DOIUrl":"https://doi.org/10.1109/ASEMD.2009.5306612","url":null,"abstract":"We have undertaken research and development of superconducting cables and superconducting fault current limiters and have made significant progress in the last six years. At Puji Substation of Southern China Power Grid, a 35 kV superconducting cable system was installed and energized in 2004. In 2007, a 35 kV superconducting fault current limiter (FCL) was installed in the substation. After field tests and trial operation, this device was commissioned to live-grid operation in 2008. As of now, Puji Substation is the only substation in the world that has both superconducting cable and superconducting FCL operating in its network. The cable system consists of three 33.5 m warm dielectric superconducting cables, six terminations, and a closed cycle liquid nitrogen cooling station. Up to date, it has delivered more than 400,000,000kW·h of electricity to the customers, including 4 factories and a residential population of about 100,000. The FCL is a saturated magnetic type superconducting fault current limiter. Its performance has been tested under live-grid operation conditions. The testing results show that the FCL has low impedance at normal power transmission and reliable fault current limiting capability in a short-circuit situation. These results are in good agreement with the design expectations. Technical details of the installation, operation and some testing data for the cable and fault current limiter are reported in this article.","PeriodicalId":354649,"journal":{"name":"2009 International Conference on Applied Superconductivity and Electromagnetic Devices","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116075134","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 : 2009-10-30DOI: 10.1109/ASEMD.2009.5306662
Lingshun Liu, Kai Zhang, Shutuan Zhang
Taking core loss into account has import effect to improving the torque performance of direct field oriented control for induction motors. In this paper, the transient mathematical model of induction motor with core loss is proposed. The method is presented to minimize the loss in a variable speed and torque at the rotating coordinate, and simulated results show that the efficiency is improved evidently at light load.
{"title":"Optimal efficiency control of induction motor with, core loss","authors":"Lingshun Liu, Kai Zhang, Shutuan Zhang","doi":"10.1109/ASEMD.2009.5306662","DOIUrl":"https://doi.org/10.1109/ASEMD.2009.5306662","url":null,"abstract":"Taking core loss into account has import effect to improving the torque performance of direct field oriented control for induction motors. In this paper, the transient mathematical model of induction motor with core loss is proposed. The method is presented to minimize the loss in a variable speed and torque at the rotating coordinate, and simulated results show that the efficiency is improved evidently at light load.","PeriodicalId":354649,"journal":{"name":"2009 International Conference on Applied Superconductivity and Electromagnetic Devices","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116231595","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 : 2009-10-30DOI: 10.1109/ASEMD.2009.5306646
Jun Cai, Z. Deng, Zheyuan Liu, Tian Yao, Yuyang Mao
Accurate calculation of the flux linkage characteristics is the basis of design and control of bearingless switched reluctance motor (BSRM). In this paper, flux linkage of main-and suspended windings for a BSRM were calculated by using 3D finite element method (FEM). A new subregional fitting algorithm was proposed and a novel mathematical model of flux linkage was built by using fourier series and Levenberg-Marquardt(LM) optimization method. Based on the new model, the incremental inductance, back-emf factor and instantaneous torque were obtained. This will provide important theoretical basis for the analysis, design and control of the BSRM.
{"title":"A new flux-linkage model for bearingless switched reluctance motor","authors":"Jun Cai, Z. Deng, Zheyuan Liu, Tian Yao, Yuyang Mao","doi":"10.1109/ASEMD.2009.5306646","DOIUrl":"https://doi.org/10.1109/ASEMD.2009.5306646","url":null,"abstract":"Accurate calculation of the flux linkage characteristics is the basis of design and control of bearingless switched reluctance motor (BSRM). In this paper, flux linkage of main-and suspended windings for a BSRM were calculated by using 3D finite element method (FEM). A new subregional fitting algorithm was proposed and a novel mathematical model of flux linkage was built by using fourier series and Levenberg-Marquardt(LM) optimization method. Based on the new model, the incremental inductance, back-emf factor and instantaneous torque were obtained. This will provide important theoretical basis for the analysis, design and control of the BSRM.","PeriodicalId":354649,"journal":{"name":"2009 International Conference on Applied Superconductivity and Electromagnetic Devices","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124639372","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 : 2009-10-30DOI: 10.1109/ASEMD.2009.5306652
Wenbo Wang, Lin Lei
In this paper, we propose a modified SPIHT algorithm based on the Texture Preservation. First, make a pretreatment of piecewise linear transformation to the coefficients of designated high-frequency subbands. By the addition of this step, the small coefficients in texture subband to some extent can be retained. Then improved SPIHT algorithm's ability of label important coefficients. Experiments show that even at low bit-rate modified SPIHT algorithm has good performance on the Texture Preservation.
{"title":"Image compression algorithm based on the texture preservation","authors":"Wenbo Wang, Lin Lei","doi":"10.1109/ASEMD.2009.5306652","DOIUrl":"https://doi.org/10.1109/ASEMD.2009.5306652","url":null,"abstract":"In this paper, we propose a modified SPIHT algorithm based on the Texture Preservation. First, make a pretreatment of piecewise linear transformation to the coefficients of designated high-frequency subbands. By the addition of this step, the small coefficients in texture subband to some extent can be retained. Then improved SPIHT algorithm's ability of label important coefficients. Experiments show that even at low bit-rate modified SPIHT algorithm has good performance on the Texture Preservation.","PeriodicalId":354649,"journal":{"name":"2009 International Conference on Applied Superconductivity and Electromagnetic Devices","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114359043","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 : 2009-10-30DOI: 10.1109/ASEMD.2009.5306613
Yi Xie, V. Selvamanickam, M. Marchevsky, Yimin Chen, X. Xiong, A. Rar, K. Lenseth, Y. Qiao, D. Hazelton, A. Knoll, J. Dackow
REBa2Cu3O7−δ (REBCO) coated conductor, namely second generation high-temperature (2G HTS) wire, holds enormous promise for many real world applications such as electrical power transmission cables, superconducting magnets, energy storage, fault current limiters, motors, generators and medical devices. SuperPower is developing and manufacturing high-performance 2G HTS wire based on two high-throughput processes: IBAD-MgO for texture buffer and MOCVD for the HTS layer. Tremendous progress has been made in 2G HTS wire technology development and manufacturing in the past few years. In this paper, we report our overall achievements in kilometer long wire fabrication reaching a minimum Ic of 282 A/cm-w over 1,065 m, practical conductor development for ac application and recent achievement in high-field coils and quench detection technique.
REBa2Cu3O7−δ (REBCO)涂层导体，即第二代高温(2G HTS)电线，在许多现实世界的应用中具有巨大的前景，例如电力传输电缆，超导磁体，储能，故障电流限制器，电机，发电机和医疗设备。SuperPower正在开发和制造基于两种高吞吐量工艺的高性能2G HTS线:用于纹理缓冲的IBAD-MgO和用于HTS层的MOCVD。在过去的几年里，2G高温超导线材技术的开发和制造取得了巨大的进步。在本文中，我们报告了我们在达到最小Ic为282 a /cm-w / 1065 m的千米长导线制造方面的总体成就，交流应用的实用导体的开发以及在高场线圈和淬火检测技术方面的最新成就。
{"title":"Second-generation HTS wire manufacturing and technology advancement at superpower","authors":"Yi Xie, V. Selvamanickam, M. Marchevsky, Yimin Chen, X. Xiong, A. Rar, K. Lenseth, Y. Qiao, D. Hazelton, A. Knoll, J. Dackow","doi":"10.1109/ASEMD.2009.5306613","DOIUrl":"https://doi.org/10.1109/ASEMD.2009.5306613","url":null,"abstract":"REBa2Cu3O7−δ (REBCO) coated conductor, namely second generation high-temperature (2G HTS) wire, holds enormous promise for many real world applications such as electrical power transmission cables, superconducting magnets, energy storage, fault current limiters, motors, generators and medical devices. SuperPower is developing and manufacturing high-performance 2G HTS wire based on two high-throughput processes: IBAD-MgO for texture buffer and MOCVD for the HTS layer. Tremendous progress has been made in 2G HTS wire technology development and manufacturing in the past few years. In this paper, we report our overall achievements in kilometer long wire fabrication reaching a minimum Ic of 282 A/cm-w over 1,065 m, practical conductor development for ac application and recent achievement in high-field coils and quench detection technique.","PeriodicalId":354649,"journal":{"name":"2009 International Conference on Applied Superconductivity and Electromagnetic Devices","volume":"111 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115849574","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 : 2009-10-30DOI: 10.1109/ASEMD.2009.5306619
Danny Sutanto, K. Ding
This paper described a novel design of a hybrid fuel cell and energy storage system using high temperature superconducting energy storage system (HT-SMES) or batteries to meet fast changing load. The power electronic switches in the converter of the energy storage system are controlled in such a way that the amplitude and waveform of the inverter output current from the fuel cell is tightly regulated to follow a sinusoidal reference waveform. In this way, the energy storage system is used to supply the fast changing part of the load and the fuel cell system continuously supplies a constant full load demand. The SABER simulation results during motor starting will be presented and discussed.
{"title":"Hybrid fuel cell and energy storage systems using superconducting coil or batteries for clean electricity generation","authors":"Danny Sutanto, K. Ding","doi":"10.1109/ASEMD.2009.5306619","DOIUrl":"https://doi.org/10.1109/ASEMD.2009.5306619","url":null,"abstract":"This paper described a novel design of a hybrid fuel cell and energy storage system using high temperature superconducting energy storage system (HT-SMES) or batteries to meet fast changing load. The power electronic switches in the converter of the energy storage system are controlled in such a way that the amplitude and waveform of the inverter output current from the fuel cell is tightly regulated to follow a sinusoidal reference waveform. In this way, the energy storage system is used to supply the fast changing part of the load and the fuel cell system continuously supplies a constant full load demand. The SABER simulation results during motor starting will be presented and discussed.","PeriodicalId":354649,"journal":{"name":"2009 International Conference on Applied Superconductivity and Electromagnetic Devices","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132988421","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 : 2009-10-30DOI: 10.1109/ASEMD.2009.5306637
Ye Yang, C. Ke, Lei Wang, Huihui Sun, Cuihua Cheng, Yong Zhao
Mg1−xFexB2 superconductor was prepared by in situ solid state reaction to study the effects of nano-iron doping on the superconductivity of MgB2. Two kinds of nano-iron sources were used: nano-iron particles and nano-iron wires. It was found that crystal structure was not affected by nano-iron doping for either form of dopant source. Tc, Jc, and Hirr were severely suppressed by iron nano-particles doping. In contrast, with iron nano-wires doping, Tc of the MgB2 superconductors were not changed remarkably, while their Jc and Hirr were slightly enhanced at all the temperature ranges investigated in this work. Under 4 T field, the sample doped with 1 % wt iron nano-wires reached the highest Jc of 1.1×104 A/cm2 at 10 K and 2.2×102 A/cm2 at 20 K, respectively. It was argued that the Fe nano-wires may be introduced into MgB2 as external pinning centers in high field region.
{"title":"The effects of nano-scale iron doping on superconductivity and microstructure of MgB2 bulk","authors":"Ye Yang, C. Ke, Lei Wang, Huihui Sun, Cuihua Cheng, Yong Zhao","doi":"10.1109/ASEMD.2009.5306637","DOIUrl":"https://doi.org/10.1109/ASEMD.2009.5306637","url":null,"abstract":"Mg<inf>1−x</inf>Fe<inf>x</inf>B<inf>2</inf> superconductor was prepared by in situ solid state reaction to study the effects of nano-iron doping on the superconductivity of MgB<inf>2</inf>. Two kinds of nano-iron sources were used: nano-iron particles and nano-iron wires. It was found that crystal structure was not affected by nano-iron doping for either form of dopant source. T<inf>c</inf>, J<inf>c</inf>, and H<inf>irr</inf> were severely suppressed by iron nano-particles doping. In contrast, with iron nano-wires doping, T<inf>c</inf> of the MgB<inf>2</inf> superconductors were not changed remarkably, while their J<inf>c</inf> and H<inf>irr</inf> were slightly enhanced at all the temperature ranges investigated in this work. Under 4 T field, the sample doped with 1 % wt iron nano-wires reached the highest J<inf>c</inf> of 1.1×10<sup>4</sup> A/cm<sup>2</sup> at 10 K and 2.2×10<sup>2</sup> A/cm<sup>2</sup> at 20 K, respectively. It was argued that the Fe nano-wires may be introduced into MgB<inf>2</inf> as external pinning centers in high field region.","PeriodicalId":354649,"journal":{"name":"2009 International Conference on Applied Superconductivity and Electromagnetic Devices","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133385671","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 : 2009-10-30DOI: 10.1109/ASEMD.2009.5306649
Zeyuan Liu, Z. Deng, Jun Cai, Yuanyuan Wu, Shishan Wang
This paper presents a method of optimizing number of turns of the main and radial force winding for a bearingless switched reluctance motor (BSRM) with 12/8 teeth configuration based on its mathematical model. The radial force and torque of BSRM are analyzed on condition of different combinations of the magnetomotive force of two kinds of windings. The winding configuration has a strongly influence on the performance of BSRM. Effects of two kind of winding arrangements on mutual inductances for BSRM are analyzed, and its optimal winding structures are proposed.
{"title":"Optimal design of a bearingless switched reluctance motor","authors":"Zeyuan Liu, Z. Deng, Jun Cai, Yuanyuan Wu, Shishan Wang","doi":"10.1109/ASEMD.2009.5306649","DOIUrl":"https://doi.org/10.1109/ASEMD.2009.5306649","url":null,"abstract":"This paper presents a method of optimizing number of turns of the main and radial force winding for a bearingless switched reluctance motor (BSRM) with 12/8 teeth configuration based on its mathematical model. The radial force and torque of BSRM are analyzed on condition of different combinations of the magnetomotive force of two kinds of windings. The winding configuration has a strongly influence on the performance of BSRM. Effects of two kind of winding arrangements on mutual inductances for BSRM are analyzed, and its optimal winding structures are proposed.","PeriodicalId":354649,"journal":{"name":"2009 International Conference on Applied Superconductivity and Electromagnetic Devices","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127820819","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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