Pub Date : 2006-09-01DOI: 10.1109/DEIV.2006.357336
R. Parashar, A. Baker, A. Sitzia
Vacuum interrupters form the key component of a medium voltage (MV) vacuum switchgear design. Vacuum interrupter technology is now well established and key manufacturers across the world are routinely producing interrupters for ratings up to 52kVrms. Manufacturers have focused on reducing the cost of interrupter components by adapting to more efficient contact geometry, improved contact materials, finite element modelling for improved field distribution and new processing techniques. However, these methods are now such that further cost reductions are becoming difficult. This may become a driving force to improve design capability with further scope for cost reductions. For example, in the low voltage (LV) sector (< lkV) vacuum interrupters are available at costs that are much higher than air break switches. Similarly, in the high voltage (HV) sector (52kV les Ur les 145kV) no efficient and cost effective designs are available, and in addition, radiation related safety concerns must be considered. This paper explores the existing switchgear portfolio in LV, MV and HV segments, corresponding demand and emerging market needs for vacuum interrupters and explores areas where the technology needs to be developed and new products brought to market
{"title":"Challenges For Vacuum Interrupter Design","authors":"R. Parashar, A. Baker, A. Sitzia","doi":"10.1109/DEIV.2006.357336","DOIUrl":"https://doi.org/10.1109/DEIV.2006.357336","url":null,"abstract":"Vacuum interrupters form the key component of a medium voltage (MV) vacuum switchgear design. Vacuum interrupter technology is now well established and key manufacturers across the world are routinely producing interrupters for ratings up to 52kVrms. Manufacturers have focused on reducing the cost of interrupter components by adapting to more efficient contact geometry, improved contact materials, finite element modelling for improved field distribution and new processing techniques. However, these methods are now such that further cost reductions are becoming difficult. This may become a driving force to improve design capability with further scope for cost reductions. For example, in the low voltage (LV) sector (< lkV) vacuum interrupters are available at costs that are much higher than air break switches. Similarly, in the high voltage (HV) sector (52kV les Ur les 145kV) no efficient and cost effective designs are available, and in addition, radiation related safety concerns must be considered. This paper explores the existing switchgear portfolio in LV, MV and HV segments, corresponding demand and emerging market needs for vacuum interrupters and explores areas where the technology needs to be developed and new products brought to market","PeriodicalId":369861,"journal":{"name":"2006 International Symposium on Discharges and Electrical Insulation in Vacuum","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125894766","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 : 2006-09-01DOI: 10.1109/DEIV.2006.357387
A. Fukamachi, M. Watanabe, A. Okino, K. Ko, E. Hotta
Non-thermal plasma technologies using electrical discharges or electron beam irradiation offer an energy- and cost-efficient approach to the decomposition of gaseous compounds. We have developed a low-energy secondary emission electron gun (SEEG) using wire ion plasma source (WIPS) for gaseous pollutant treatment. The devise has some inherent advantages such as compact in size, wide and uniform electron beam. In this work, divergence of electron beam energy was measured and NO removal characteristics have been studied under increasing gun voltage and changing dimension of gas treatment chamber. It has been observed that the smaller chamber gives better removal efficiency of NO and we are trying to apply this device to VOC treatment
{"title":"Application of low-energy secondary emission electron gun for VOC treatment","authors":"A. Fukamachi, M. Watanabe, A. Okino, K. Ko, E. Hotta","doi":"10.1109/DEIV.2006.357387","DOIUrl":"https://doi.org/10.1109/DEIV.2006.357387","url":null,"abstract":"Non-thermal plasma technologies using electrical discharges or electron beam irradiation offer an energy- and cost-efficient approach to the decomposition of gaseous compounds. We have developed a low-energy secondary emission electron gun (SEEG) using wire ion plasma source (WIPS) for gaseous pollutant treatment. The devise has some inherent advantages such as compact in size, wide and uniform electron beam. In this work, divergence of electron beam energy was measured and NO removal characteristics have been studied under increasing gun voltage and changing dimension of gas treatment chamber. It has been observed that the smaller chamber gives better removal efficiency of NO and we are trying to apply this device to VOC treatment","PeriodicalId":369861,"journal":{"name":"2006 International Symposium on Discharges and Electrical Insulation in Vacuum","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129935563","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 : 2006-09-01DOI: 10.1109/DEIV.2006.357415
H. Hayashi, M. Cho, H. Kuninaka
High specific impulse ion propulsion is of concern as primary propulsion system for various interplanetary explorers. A high specific impulse microwave discharge ion engine has been developed in Japan Aerospace Exploration Agency (JAXA) since 2003. The aim of this development is achieving a specific impulse of 10,000sec with an ion acceleration voltage of 15kV. New electro-static grid made of carbon-carbon composite material and various high voltage insulating components such as a DC block and a propellant isolator were developed. The authors fabricated a prototype model of the ion engine, and successfully operated it. The paper describes the outline and the experimental result of demonstration test of the high specific impulse microwave discharge ion engine
{"title":"High Specific Impulse Microwave Discharge Ion Engine for Interplanetary Explorer","authors":"H. Hayashi, M. Cho, H. Kuninaka","doi":"10.1109/DEIV.2006.357415","DOIUrl":"https://doi.org/10.1109/DEIV.2006.357415","url":null,"abstract":"High specific impulse ion propulsion is of concern as primary propulsion system for various interplanetary explorers. A high specific impulse microwave discharge ion engine has been developed in Japan Aerospace Exploration Agency (JAXA) since 2003. The aim of this development is achieving a specific impulse of 10,000sec with an ion acceleration voltage of 15kV. New electro-static grid made of carbon-carbon composite material and various high voltage insulating components such as a DC block and a propellant isolator were developed. The authors fabricated a prototype model of the ion engine, and successfully operated it. The paper describes the outline and the experimental result of demonstration test of the high specific impulse microwave discharge ion engine","PeriodicalId":369861,"journal":{"name":"2006 International Symposium on Discharges and Electrical Insulation in Vacuum","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130139345","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 : 2006-09-01DOI: 10.1109/DEIV.2006.357270
E. V. Lanen, R. Smeets, M. Popov, L. V. D. Sluis
High resolution measurements on the post-arc current in vacuum circuit breakers reveal a period, immediately following current-zero, in which the voltage remains practically zero. The most widely used model for simulating the interaction between the post-arc current with the electrical circuit lacks a proper explanation for this event, and hence it needs to be complemented. We demonstrate that the breaker's electrical behaviour during this zero-voltage period can be explained by using the theory of a Langmuir probe. Such probes are used to investigate plasma properties, such as the ion density and the electron temperature, and we extrapolate its theory to the vacuum circuit breaker. The simulation results obtained with this model are in good agreement with measured data
{"title":"Current-Zero Characteristics of a Vacuum Circuit Breaker at Short-Circuit Current Interruption","authors":"E. V. Lanen, R. Smeets, M. Popov, L. V. D. Sluis","doi":"10.1109/DEIV.2006.357270","DOIUrl":"https://doi.org/10.1109/DEIV.2006.357270","url":null,"abstract":"High resolution measurements on the post-arc current in vacuum circuit breakers reveal a period, immediately following current-zero, in which the voltage remains practically zero. The most widely used model for simulating the interaction between the post-arc current with the electrical circuit lacks a proper explanation for this event, and hence it needs to be complemented. We demonstrate that the breaker's electrical behaviour during this zero-voltage period can be explained by using the theory of a Langmuir probe. Such probes are used to investigate plasma properties, such as the ion density and the electron temperature, and we extrapolate its theory to the vacuum circuit breaker. The simulation results obtained with this model are in good agreement with measured data","PeriodicalId":369861,"journal":{"name":"2006 International Symposium on Discharges and Electrical Insulation in Vacuum","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129289693","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 : 2006-09-01DOI: 10.1109/DEIV.2006.357392
K. Chung, H.D. Jung, J. Park, Y. Hwang
A compact cylindrical neutron generator using RF (radio-frequency) inductively-coupled plasma has been developed in radially convergent ion beam extraction configuration. Since the RF plasma source has characteristics of high plasma density, low gas pressure, high mono-atomic fraction, and long lifetime, it is known to be suitable for generating high neutron yield with high efficiency. In order to increase neutron yield, the energy and the number of incident particles should be as large as possible. Since the cylindrical source can be operated as a line source configuration the extracted beam current can be increased easily. In this paper, experimental results with the cylindrical neutron generator are given and the operating characteristics of the device are discussed to improve neutron generation efficiency
{"title":"Development of a Cylindrical Neutron Generator using RF-driven Plasma","authors":"K. Chung, H.D. Jung, J. Park, Y. Hwang","doi":"10.1109/DEIV.2006.357392","DOIUrl":"https://doi.org/10.1109/DEIV.2006.357392","url":null,"abstract":"A compact cylindrical neutron generator using RF (radio-frequency) inductively-coupled plasma has been developed in radially convergent ion beam extraction configuration. Since the RF plasma source has characteristics of high plasma density, low gas pressure, high mono-atomic fraction, and long lifetime, it is known to be suitable for generating high neutron yield with high efficiency. In order to increase neutron yield, the energy and the number of incident particles should be as large as possible. Since the cylindrical source can be operated as a line source configuration the extracted beam current can be increased easily. In this paper, experimental results with the cylindrical neutron generator are given and the operating characteristics of the device are discussed to improve neutron generation efficiency","PeriodicalId":369861,"journal":{"name":"2006 International Symposium on Discharges and Electrical Insulation in Vacuum","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129490003","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 : 2006-09-01DOI: 10.1109/DEIV.2006.357412
H. Fujii, I. Kanja, T. Hasegawa, H. Osuga, K. Matsui
This paper deals with the surface flashover characteristics of dielectric material during electron beam irradiation in vacuum in order to design the conductive patterns on printed circuit boards used inside a spacecraft adequately. The dielectric material and the electrodes printed on it were irradiated with electrons of the energy of 3-10keV. DC high voltage was applied between the two electrodes during electron irradiation. The voltage was increased step-wisely until the surface flashover occurred on the dielectric. We obtained the result that the surface flashover voltage increased with the insulation distance between the electrodes. However, electron irradiation caused the flashover voltage to lower. The flashover voltage characteristics were obtained as parameters of the electrode distance and the energy of the electron beam
{"title":"Surface Flashover on Printed Circuit Boards in Vacuum under Electron Beam Irradiation","authors":"H. Fujii, I. Kanja, T. Hasegawa, H. Osuga, K. Matsui","doi":"10.1109/DEIV.2006.357412","DOIUrl":"https://doi.org/10.1109/DEIV.2006.357412","url":null,"abstract":"This paper deals with the surface flashover characteristics of dielectric material during electron beam irradiation in vacuum in order to design the conductive patterns on printed circuit boards used inside a spacecraft adequately. The dielectric material and the electrodes printed on it were irradiated with electrons of the energy of 3-10keV. DC high voltage was applied between the two electrodes during electron irradiation. The voltage was increased step-wisely until the surface flashover occurred on the dielectric. We obtained the result that the surface flashover voltage increased with the insulation distance between the electrodes. However, electron irradiation caused the flashover voltage to lower. The flashover voltage characteristics were obtained as parameters of the electrode distance and the energy of the electron beam","PeriodicalId":369861,"journal":{"name":"2006 International Symposium on Discharges and Electrical Insulation in Vacuum","volume":"120 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128024878","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 : 2006-09-01DOI: 10.1109/DEIV.2006.357373
Y. Sung, T. Yuji, T. Sakoda
Characteristics of radio-frequency (RF) plasma-enhanced vapor deposition (PE-CVD) for the growth of carbon nanotubes (CNTs) in a CH 4/N2 mixed gas were investigated through characterization of the prepared CNTs and a numerical simulation. The preparation of the CNTs was performed by the single chamber plasma process where the catalyst sputter deposition using a capacitively coupled plasma (CCP) and the PE-CVD using an inductively coupled plasma were carried out in the same discharge chamber. The plasma chemistry which is useful for optimizing preparation conditions was evaluated using the numerical code which could calculate the temporal evolution of particle densities in the plasma. The results showed the usefulness of the single chamber process system. It was also found that CH4, HCN and C2H6 radicals mainly contributed to the growth of CNTs
{"title":"RF PE-CVD Characteristics for the Growth of Carbon Nanotubes in a CH4/N2 mixed gas","authors":"Y. Sung, T. Yuji, T. Sakoda","doi":"10.1109/DEIV.2006.357373","DOIUrl":"https://doi.org/10.1109/DEIV.2006.357373","url":null,"abstract":"Characteristics of radio-frequency (RF) plasma-enhanced vapor deposition (PE-CVD) for the growth of carbon nanotubes (CNTs) in a CH 4/N2 mixed gas were investigated through characterization of the prepared CNTs and a numerical simulation. The preparation of the CNTs was performed by the single chamber plasma process where the catalyst sputter deposition using a capacitively coupled plasma (CCP) and the PE-CVD using an inductively coupled plasma were carried out in the same discharge chamber. The plasma chemistry which is useful for optimizing preparation conditions was evaluated using the numerical code which could calculate the temporal evolution of particle densities in the plasma. The results showed the usefulness of the single chamber process system. It was also found that CH4, HCN and C2H6 radicals mainly contributed to the growth of CNTs","PeriodicalId":369861,"journal":{"name":"2006 International Symposium on Discharges and Electrical Insulation in Vacuum","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128586392","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}
In this paper, a two-dimensional statistical model for a single cathode spot of vacuum arc with copper cathode has been established to simulate its random walk and retrograde motion under external transverse magnetic field. In this preliminary work, a parameter, A, which was not yet related with the strength of applied transverse magnetic field in present work, was used to denote the different probabilities of cathode spot motion in Amperes direction and retrograde direction. With this model, the distribution of the probability density of cathode spot occurring in different area on cathode surface was simulated at different arcing time
{"title":"Statistical Simulation on the Random and Retrograde Motion of Single Cathode Spot of Vacuum Arc","authors":"Z. Shi, Jia Xiao, S. Jia, Yue Zhang, Lijun Wang","doi":"10.3131/jvsj.50.337","DOIUrl":"https://doi.org/10.3131/jvsj.50.337","url":null,"abstract":"In this paper, a two-dimensional statistical model for a single cathode spot of vacuum arc with copper cathode has been established to simulate its random walk and retrograde motion under external transverse magnetic field. In this preliminary work, a parameter, A, which was not yet related with the strength of applied transverse magnetic field in present work, was used to denote the different probabilities of cathode spot motion in Amperes direction and retrograde direction. With this model, the distribution of the probability density of cathode spot occurring in different area on cathode surface was simulated at different arcing time","PeriodicalId":369861,"journal":{"name":"2006 International Symposium on Discharges and Electrical Insulation in Vacuum","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125050191","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 : 2006-09-01DOI: 10.1109/DEIV.2006.357346
Yundong Cao, Feng Li, Xiaoming Liu, Chunguang Hou
An intelligent releaser with embedded network control function is introduced. And the field bus technology, embedded technology, Ethernet technology and intelligent protection control technology are integrated and applied to the actual products. Based on the front edge of the world's intelligent electric appliance, the mining vacuum circuit breaker (VCB) of low voltage and large current, which has protective and communication function, has been developed. Moreover, the intelligent protection and control function, network communication and monitor function are implemented by adding the intelligent control module and adopting embedded system and TCP/IP protocol. The system covers the main functions, such as, the protection of short circuit, over-voltage, under voltage, overload and earthing, the real-time communication between Ethernet and terminal computer, the display about the current and voltage of circuit and faults information, the historical data review and print. In order to increase the efficiency, realize the monitoring on-line for remote distance, the intelligent VCB based on the network, communication, openness and compatibility has been developed
{"title":"Research on Intelligent Vacuum Circuit Breaker Controller based on Embedded Network Control System","authors":"Yundong Cao, Feng Li, Xiaoming Liu, Chunguang Hou","doi":"10.1109/DEIV.2006.357346","DOIUrl":"https://doi.org/10.1109/DEIV.2006.357346","url":null,"abstract":"An intelligent releaser with embedded network control function is introduced. And the field bus technology, embedded technology, Ethernet technology and intelligent protection control technology are integrated and applied to the actual products. Based on the front edge of the world's intelligent electric appliance, the mining vacuum circuit breaker (VCB) of low voltage and large current, which has protective and communication function, has been developed. Moreover, the intelligent protection and control function, network communication and monitor function are implemented by adding the intelligent control module and adopting embedded system and TCP/IP protocol. The system covers the main functions, such as, the protection of short circuit, over-voltage, under voltage, overload and earthing, the real-time communication between Ethernet and terminal computer, the display about the current and voltage of circuit and faults information, the historical data review and print. In order to increase the efficiency, realize the monitoring on-line for remote distance, the intelligent VCB based on the network, communication, openness and compatibility has been developed","PeriodicalId":369861,"journal":{"name":"2006 International Symposium on Discharges and Electrical Insulation in Vacuum","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131329639","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 : 2006-09-01DOI: 10.1109/DEIV.2006.357226
K. Nitta, S. Matsuoka, M. Chiba, K. Hidaka
This paper studies the discharge development in a micro gap between metal materials in air experimentally and analytically. As a high voltage side electrode is stressed by different voltages at a fixed gap length with UV irradiation, the electrical breakdown voltage is measured as a function of the time lag. The measured time lag until the spark breakdown ranges from 10-1 to 10-4 s between 190 Torr and 760Torr. Using the measured time lag to the breakdown, the formative time lag to breakdown is obtained and the formative time lag to breakdown is calculated by gammai, gammap and gammam. The calculation results of the formative time lag agree with the experiment results. The obtained values of gamma i, gammap and gammam are applied to the estimate the formative time lag to breakdown at various pressures, from 190 Torr to 760 Torr, between metal electrodes in a uniform electric field
{"title":"Formative Time Lag to Breakdown in Micro Gap at Low Atmospheric Pressure","authors":"K. Nitta, S. Matsuoka, M. Chiba, K. Hidaka","doi":"10.1109/DEIV.2006.357226","DOIUrl":"https://doi.org/10.1109/DEIV.2006.357226","url":null,"abstract":"This paper studies the discharge development in a micro gap between metal materials in air experimentally and analytically. As a high voltage side electrode is stressed by different voltages at a fixed gap length with UV irradiation, the electrical breakdown voltage is measured as a function of the time lag. The measured time lag until the spark breakdown ranges from 10-1 to 10-4 s between 190 Torr and 760Torr. Using the measured time lag to the breakdown, the formative time lag to breakdown is obtained and the formative time lag to breakdown is calculated by gammai, gammap and gammam. The calculation results of the formative time lag agree with the experiment results. The obtained values of gamma i, gammap and gammam are applied to the estimate the formative time lag to breakdown at various pressures, from 190 Torr to 760 Torr, between metal electrodes in a uniform electric field","PeriodicalId":369861,"journal":{"name":"2006 International Symposium on Discharges and Electrical Insulation in Vacuum","volume":"96 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130048999","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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