Pub Date : 1994-07-03DOI: 10.1109/ICPADM.1994.413926
U. Gafvert, E. Ildstad
The purpose of this paper is to analyse voltage return measurements starting from a theoretical analysis of a series combination of several dielectric materials. Each material is characterised by its conductivity, permittivity and dielectric response function. Computer simulations have been performed in order to interpret results of laboratory experiments performed on a test cell consisting of transformer press board in series with oil insulation. For short (<1000 s) charging and discharging times the return voltage is mainly determined by interfacial polarisation. To obtain information about the dielectric relaxation and polarisation properties of the bulk of the pressboard insulation it is important to use long measuring times.<>
{"title":"Modelling return voltage measurements of multi-layer insulation systems","authors":"U. Gafvert, E. Ildstad","doi":"10.1109/ICPADM.1994.413926","DOIUrl":"https://doi.org/10.1109/ICPADM.1994.413926","url":null,"abstract":"The purpose of this paper is to analyse voltage return measurements starting from a theoretical analysis of a series combination of several dielectric materials. Each material is characterised by its conductivity, permittivity and dielectric response function. Computer simulations have been performed in order to interpret results of laboratory experiments performed on a test cell consisting of transformer press board in series with oil insulation. For short (<1000 s) charging and discharging times the return voltage is mainly determined by interfacial polarisation. To obtain information about the dielectric relaxation and polarisation properties of the bulk of the pressboard insulation it is important to use long measuring times.<<ETX>>","PeriodicalId":331058,"journal":{"name":"Proceedings of 1994 4th International Conference on Properties and Applications of Dielectric Materials (ICPADM)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122592759","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 : 1994-07-03DOI: 10.1109/ICPADM.1994.414052
M. Farzaneh, J. Kienicki, R. Martin
This paper presents the results of a laboratory study of AC flashover performance of an EPDM (ethylene propylene diene monomer) composite insulator covered with wet-grown ice formed from supercooled droplets. Withstand voltage (V/sub ws/) of the insulator string was determined using a method based on IEC 507. The results of V/sub ws/ obtained using EPDM were compared to those measured using IEEE standard insulators iced under similar conditions. This study is of particular usefulness in the design of compact lines using composite insulators.<>
{"title":"A laboratory investigation of the flashover performance of outdoor insulators covered with ice","authors":"M. Farzaneh, J. Kienicki, R. Martin","doi":"10.1109/ICPADM.1994.414052","DOIUrl":"https://doi.org/10.1109/ICPADM.1994.414052","url":null,"abstract":"This paper presents the results of a laboratory study of AC flashover performance of an EPDM (ethylene propylene diene monomer) composite insulator covered with wet-grown ice formed from supercooled droplets. Withstand voltage (V/sub ws/) of the insulator string was determined using a method based on IEC 507. The results of V/sub ws/ obtained using EPDM were compared to those measured using IEEE standard insulators iced under similar conditions. This study is of particular usefulness in the design of compact lines using composite insulators.<<ETX>>","PeriodicalId":331058,"journal":{"name":"Proceedings of 1994 4th International Conference on Properties and Applications of Dielectric Materials (ICPADM)","volume":"99 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124984804","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 : 1994-07-03DOI: 10.1109/ICPADM.1994.414096
C. R. Evert, P. de Klerk
The major electricity utility in South Africa, Eskom has addressed the problem of fire induced faults and in particular, sugar cane fires, in the 275 kV and 400 kV transmission network by means of early detection with the aid of appropriate HF background noise identification. Fires under these lines cause increased levels of conductor corona which generate, inter alia, increased levels of background radio noise detectable in the carrier system communication channels. A brief overview of previous work done is presented followed by Eskom's latest research and developments related to both a prototype fire detection device and monitoring other deficiencies in the substation and transmission network.<>
{"title":"Corona noise as a diagnostic tool","authors":"C. R. Evert, P. de Klerk","doi":"10.1109/ICPADM.1994.414096","DOIUrl":"https://doi.org/10.1109/ICPADM.1994.414096","url":null,"abstract":"The major electricity utility in South Africa, Eskom has addressed the problem of fire induced faults and in particular, sugar cane fires, in the 275 kV and 400 kV transmission network by means of early detection with the aid of appropriate HF background noise identification. Fires under these lines cause increased levels of conductor corona which generate, inter alia, increased levels of background radio noise detectable in the carrier system communication channels. A brief overview of previous work done is presented followed by Eskom's latest research and developments related to both a prototype fire detection device and monitoring other deficiencies in the substation and transmission network.<<ETX>>","PeriodicalId":331058,"journal":{"name":"Proceedings of 1994 4th International Conference on Properties and Applications of Dielectric Materials (ICPADM)","volume":"86 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123774288","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 : 1994-07-03DOI: 10.1109/ICPADM.1994.414079
R. Włodek, Z. Florkowski, P. Zydroń
In some cases of partial discharge (PD) measurements it is necessary to improve the signal-to-noise and disturbance ratio, particularly when the measurements are to be carried out on large capacitance objects. The paper presents the partial discharge measurement method based on signal theory. The measuring system presented in the paper can be used in such conditions. It is based on the method of multiple accumulation and averaging of the detected signal, which is the sum of the disturbance signal and of the partial discharge one. After such averaging the PD signal-to-noise-and-disturbance ratio increases and the phase location of the partial discharge signal can be distinguished from the disturbances and noises. The essential theoretical conditions of application of this method are discussed. The computer-aided system for data acquisition and following evaluation is described. The measurement results obtained in controlled model conditions are presented. The discussion of resultant improvement of signal-to-noise and disturbance ratio is given. The critical comparison with other methods which are being used for this aim is presented.<>
{"title":"Improvement of signal to noise ratio in partial discharge measurements","authors":"R. Włodek, Z. Florkowski, P. Zydroń","doi":"10.1109/ICPADM.1994.414079","DOIUrl":"https://doi.org/10.1109/ICPADM.1994.414079","url":null,"abstract":"In some cases of partial discharge (PD) measurements it is necessary to improve the signal-to-noise and disturbance ratio, particularly when the measurements are to be carried out on large capacitance objects. The paper presents the partial discharge measurement method based on signal theory. The measuring system presented in the paper can be used in such conditions. It is based on the method of multiple accumulation and averaging of the detected signal, which is the sum of the disturbance signal and of the partial discharge one. After such averaging the PD signal-to-noise-and-disturbance ratio increases and the phase location of the partial discharge signal can be distinguished from the disturbances and noises. The essential theoretical conditions of application of this method are discussed. The computer-aided system for data acquisition and following evaluation is described. The measurement results obtained in controlled model conditions are presented. The discussion of resultant improvement of signal-to-noise and disturbance ratio is given. The critical comparison with other methods which are being used for this aim is presented.<<ETX>>","PeriodicalId":331058,"journal":{"name":"Proceedings of 1994 4th International Conference on Properties and Applications of Dielectric Materials (ICPADM)","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131574581","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 : 1994-07-03DOI: 10.1109/ICPADM.1994.414049
M. Ishida, Y. Ikeda, N. Naohara, H. Mitsui, T. Kuroki
Development of sodium immersed type electro-magnetic pumps (EMP) is expected to improve the reliability, safety, maintainability, and construction cost of FBR compared with the conventional mechanical pumps. To realize electro-magnetic pumps, establishment of a high-temperature-resist electrical insulating system is indispensable. The authors had selected a mica-alumina combination for the insulating system at temperatures higher than 500/spl deg/C. Using this insulating system, an ageing pre-test was performed. The ageing condition was to apply 1.5 kV AC voltage in a nitrogen atmosphere at 550/spl deg/C for 4000 hours. The dielectric properties before and after ageing were measured to understand the tendency of temporal change in ageing. In this result, dielectric performance after ageing was improved compared with the initial one. This phenomenon was clarified to be caused by a decrease of organic component in the insulation. Also, the possibility of the thermal runaway was considered to be higher as a dielectric breakdown mechanism.<>
{"title":"Development of insulating system for FBR electro-magnetic pump","authors":"M. Ishida, Y. Ikeda, N. Naohara, H. Mitsui, T. Kuroki","doi":"10.1109/ICPADM.1994.414049","DOIUrl":"https://doi.org/10.1109/ICPADM.1994.414049","url":null,"abstract":"Development of sodium immersed type electro-magnetic pumps (EMP) is expected to improve the reliability, safety, maintainability, and construction cost of FBR compared with the conventional mechanical pumps. To realize electro-magnetic pumps, establishment of a high-temperature-resist electrical insulating system is indispensable. The authors had selected a mica-alumina combination for the insulating system at temperatures higher than 500/spl deg/C. Using this insulating system, an ageing pre-test was performed. The ageing condition was to apply 1.5 kV AC voltage in a nitrogen atmosphere at 550/spl deg/C for 4000 hours. The dielectric properties before and after ageing were measured to understand the tendency of temporal change in ageing. In this result, dielectric performance after ageing was improved compared with the initial one. This phenomenon was clarified to be caused by a decrease of organic component in the insulation. Also, the possibility of the thermal runaway was considered to be higher as a dielectric breakdown mechanism.<<ETX>>","PeriodicalId":331058,"journal":{"name":"Proceedings of 1994 4th International Conference on Properties and Applications of Dielectric Materials (ICPADM)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131810432","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 : 1994-07-03DOI: 10.1109/ICPADM.1994.413928
M.S.A. Minhas, D. Hoch, J. Reynders
The results of an experimental investigation into the heat transfer, flame retardency and partial discharge extinction properties of an optimum mixture of pure transformer oil with perchlorethylene are presented. When transformer oil is mixed with perchlorethylene the heat transfer, partial discharge properties as well as the flame retardency of the mixture are enhanced. Two different mixtures were used in temperature rise tests on distribution transformers. The partial discharge performance was assessed by refurbishing a HV current transformer with excessive partial discharge levels, simply by flushing and filling with an optimum mixture. The partial discharge level was then measured and found to have decreased significantly. Some simple observations are presented which show that the mixture possess enhanced flame retardency. The purpose of this work is to present much needed practical data on the application of mixtures in typical engineering situations.<>
{"title":"Enhancing the flame, thermal and partial discharge performance of mineral oil","authors":"M.S.A. Minhas, D. Hoch, J. Reynders","doi":"10.1109/ICPADM.1994.413928","DOIUrl":"https://doi.org/10.1109/ICPADM.1994.413928","url":null,"abstract":"The results of an experimental investigation into the heat transfer, flame retardency and partial discharge extinction properties of an optimum mixture of pure transformer oil with perchlorethylene are presented. When transformer oil is mixed with perchlorethylene the heat transfer, partial discharge properties as well as the flame retardency of the mixture are enhanced. Two different mixtures were used in temperature rise tests on distribution transformers. The partial discharge performance was assessed by refurbishing a HV current transformer with excessive partial discharge levels, simply by flushing and filling with an optimum mixture. The partial discharge level was then measured and found to have decreased significantly. Some simple observations are presented which show that the mixture possess enhanced flame retardency. The purpose of this work is to present much needed practical data on the application of mixtures in typical engineering situations.<<ETX>>","PeriodicalId":331058,"journal":{"name":"Proceedings of 1994 4th International Conference on Properties and Applications of Dielectric Materials (ICPADM)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128309164","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 : 1994-07-03DOI: 10.1109/ICPADM.1994.413983
B. Ryu, K. Lim, S. Kwon, J.H. Lee, B. Kim
When metal-oxide-semiconductor (MOS) device is exposed to radiation, the resultant effects can cause the modulation and/or degradation in device characteristics and its operating life. In this paper, the irradiation effects on MOS structure were investigated by the measurements of C-V, D-V, and I-V characteristics. From the experimental results, it is confirmed that the peak of dissipation factor is due to the interaction between majority carriers and interface states which induced by radiation. We also found that the measurements of dissipation factor could be very useful method as the evaluation tool of irradiation effects in MOS structure. The I-V characteristics could be explained by traps in the oxide created by radiation, and charges trapped at interface of Si-SiO/sub 2/.<>
{"title":"Dielectric and conduction properties in MOS capacitor irradiated under Co-60 gamma ray","authors":"B. Ryu, K. Lim, S. Kwon, J.H. Lee, B. Kim","doi":"10.1109/ICPADM.1994.413983","DOIUrl":"https://doi.org/10.1109/ICPADM.1994.413983","url":null,"abstract":"When metal-oxide-semiconductor (MOS) device is exposed to radiation, the resultant effects can cause the modulation and/or degradation in device characteristics and its operating life. In this paper, the irradiation effects on MOS structure were investigated by the measurements of C-V, D-V, and I-V characteristics. From the experimental results, it is confirmed that the peak of dissipation factor is due to the interaction between majority carriers and interface states which induced by radiation. We also found that the measurements of dissipation factor could be very useful method as the evaluation tool of irradiation effects in MOS structure. The I-V characteristics could be explained by traps in the oxide created by radiation, and charges trapped at interface of Si-SiO/sub 2/.<<ETX>>","PeriodicalId":331058,"journal":{"name":"Proceedings of 1994 4th International Conference on Properties and Applications of Dielectric Materials (ICPADM)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122222026","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 : 1994-07-03DOI: 10.1109/ICPADM.1994.414085
M. Mukai, T. Okano, M. Kawakami, S. Nishimoto, I. Kitani, K. Arii
Insulation degradation diagnoses by measuring partial discharges (PD) has been studied actively. The most important task in the study is development of new PD measuring methods where diagnostic accuracy is improved. One of these methods is the acoustic emission (AE) measuring method. By taking notice of the sound waves emitted by a PD, we are studying the relationship with the signals of sound waves and the insulation degradation in the case of using polyethylene terephthalate (PET). This paper confirms that sound waves are emitted by PD in PET and shows that the power spectrum of the measured sound waves is transformed to the frequency domain by a fast Fourier transform (FFT).<>
{"title":"Degradation diagnosis of solid insulation using sound waves emitted by partial discharge","authors":"M. Mukai, T. Okano, M. Kawakami, S. Nishimoto, I. Kitani, K. Arii","doi":"10.1109/ICPADM.1994.414085","DOIUrl":"https://doi.org/10.1109/ICPADM.1994.414085","url":null,"abstract":"Insulation degradation diagnoses by measuring partial discharges (PD) has been studied actively. The most important task in the study is development of new PD measuring methods where diagnostic accuracy is improved. One of these methods is the acoustic emission (AE) measuring method. By taking notice of the sound waves emitted by a PD, we are studying the relationship with the signals of sound waves and the insulation degradation in the case of using polyethylene terephthalate (PET). This paper confirms that sound waves are emitted by PD in PET and shows that the power spectrum of the measured sound waves is transformed to the frequency domain by a fast Fourier transform (FFT).<<ETX>>","PeriodicalId":331058,"journal":{"name":"Proceedings of 1994 4th International Conference on Properties and Applications of Dielectric Materials (ICPADM)","volume":"91 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120835522","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 : 1994-07-03DOI: 10.1109/ICPADM.1994.414050
Y. Mizuno, Y. Mitsuyama, M. Nagao, M. Kosaki
The effect of additives such as crosslinking agent and fillers on tan /spl delta/ of ethylene-propylene rubber (EPR) was examined at temperatures between 4.2 K and 300 K. Thickness dependence of tan /spl delta/ was also evaluated by using EPR films of different thickness and an extruded EPR insulated cable sample. The results show that additives increase tan /spl delta/ of relatively thin EPR films even in cryogenic temperature region, whereas the thicker samples practical to cable insulation do not give intolerable dielectric loss. The remedy to tan /spl delta/ increase due to the polymer contraction relative to shielding wires has been established.<>
在4.2 K ~ 300 K温度范围内考察了交联剂和填料等添加剂对乙丙橡胶(EPR) tan /spl delta/的影响。通过使用不同厚度的EPR薄膜和挤压的EPR绝缘电缆样品，评估了tan /spl / delta/的厚度依赖性。结果表明，即使在低温区，添加剂也会增加相对较薄的EPR薄膜的tan /spl δ /，而用于电缆绝缘的较厚样品不会产生不可容忍的介电损耗。针对聚合物相对于屏蔽丝的收缩而导致的tan /spl δ /增加，建立了补救措施。
{"title":"Dielectric properties of ethylene-propylene rubber in cryogenic temperature region","authors":"Y. Mizuno, Y. Mitsuyama, M. Nagao, M. Kosaki","doi":"10.1109/ICPADM.1994.414050","DOIUrl":"https://doi.org/10.1109/ICPADM.1994.414050","url":null,"abstract":"The effect of additives such as crosslinking agent and fillers on tan /spl delta/ of ethylene-propylene rubber (EPR) was examined at temperatures between 4.2 K and 300 K. Thickness dependence of tan /spl delta/ was also evaluated by using EPR films of different thickness and an extruded EPR insulated cable sample. The results show that additives increase tan /spl delta/ of relatively thin EPR films even in cryogenic temperature region, whereas the thicker samples practical to cable insulation do not give intolerable dielectric loss. The remedy to tan /spl delta/ increase due to the polymer contraction relative to shielding wires has been established.<<ETX>>","PeriodicalId":331058,"journal":{"name":"Proceedings of 1994 4th International Conference on Properties and Applications of Dielectric Materials (ICPADM)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132600762","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 : 1994-07-03DOI: 10.1109/ICPADM.1994.414099
U. Fromm, E. Gulski
In this paper the relation between successive partial discharges in insulating materials at DC voltage is discussed. Based on a few assumptions a DC voltage model, based on an RC-circuit, is presented and experimentally verified. Measurements of partial discharges have been made on samples containing air filled voids. For discharges of a small magnitude the model proved to be valid. Based on the model the characteristic discharge parameter mean time lag t, and mean recovery time t, have been obtained. For discharges of larger magnitude, the model is not valid. This is probably due to a different discharge mechanism, the 'streamer like' mechanism. Therefore the model could possibly be used for a recognition of the dominant discharge mechanism.<>
{"title":"Statistical behaviour of internal partial discharges at DC voltage","authors":"U. Fromm, E. Gulski","doi":"10.1109/ICPADM.1994.414099","DOIUrl":"https://doi.org/10.1109/ICPADM.1994.414099","url":null,"abstract":"In this paper the relation between successive partial discharges in insulating materials at DC voltage is discussed. Based on a few assumptions a DC voltage model, based on an RC-circuit, is presented and experimentally verified. Measurements of partial discharges have been made on samples containing air filled voids. For discharges of a small magnitude the model proved to be valid. Based on the model the characteristic discharge parameter mean time lag t, and mean recovery time t, have been obtained. For discharges of larger magnitude, the model is not valid. This is probably due to a different discharge mechanism, the 'streamer like' mechanism. Therefore the model could possibly be used for a recognition of the dominant discharge mechanism.<<ETX>>","PeriodicalId":331058,"journal":{"name":"Proceedings of 1994 4th International Conference on Properties and Applications of Dielectric Materials (ICPADM)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131044449","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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