Pub Date : 2016-07-03DOI: 10.1109/ICD.2016.7547595
M. Badard, L. Flandin, A. Combessis, A. Allais
This paper describes the effect of electric field on the structuration of carbon nanotubes in silicone oil. The particles have been dispersed in the liquid by ultrasounds and diluted in order to vary the filler content. Electrical measurements were performed under different electric fields and over time on each filler content, in order to probe the particles structuration. From a critical value, the electric field was found to both increase the conductivity of the composite and reduce percolation threshold. This effect is further enhanced with time. Spectacular percolation thresholds, as low as 22 ppm have been evidenced. This result was attributed to a strengthening effect between filler contacts. More surprisingly, the conductivity remained high after the electric field was stopped, showing the irreversible nature of this effect. In addition, an analytical model has been developed to describe the conductivity of the composite as a function of three parameters: nanotubes content, time and electric field.
{"title":"A 22 ppm ultralow percolation threshold with MWCNT","authors":"M. Badard, L. Flandin, A. Combessis, A. Allais","doi":"10.1109/ICD.2016.7547595","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547595","url":null,"abstract":"This paper describes the effect of electric field on the structuration of carbon nanotubes in silicone oil. The particles have been dispersed in the liquid by ultrasounds and diluted in order to vary the filler content. Electrical measurements were performed under different electric fields and over time on each filler content, in order to probe the particles structuration. From a critical value, the electric field was found to both increase the conductivity of the composite and reduce percolation threshold. This effect is further enhanced with time. Spectacular percolation thresholds, as low as 22 ppm have been evidenced. This result was attributed to a strengthening effect between filler contacts. More surprisingly, the conductivity remained high after the electric field was stopped, showing the irreversible nature of this effect. In addition, an analytical model has been developed to describe the conductivity of the composite as a function of three parameters: nanotubes content, time and electric field.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"378 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127386690","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547758
Zhong Zheng, Wenbo Gong, Yu Zhi-cheng, H. Du, Wei Li, Lei Shi
Detection of crackle discharge on GIS spacer from the interferences such as corona in SF6 and surface discharge is of great interests in the evaluation of GIS health conditions. The spacer insulation deteriorates quickly when such discharges occur along small crackles on spacer surface. This paper presents two approaches to differentiate three types of discharges, i.e., corona in SF6, surface discharge and crackle discharge. The former can be distinguished from the latter two by analyzing the phase resolved partial discharge pattern. Further analysis of the decomposed gases accumulated from discharges reveals that CF4 is a useful indicator for discharge on spacer, and H2 occurs only with crackle discharge. Thus the combination of the above two measures provides powerful aids in the detection of crackle discharge in GIS.
{"title":"Crackle discharge detection on GIS spacer through partial discharge test and decomposed gas analysis of SF6","authors":"Zhong Zheng, Wenbo Gong, Yu Zhi-cheng, H. Du, Wei Li, Lei Shi","doi":"10.1109/ICD.2016.7547758","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547758","url":null,"abstract":"Detection of crackle discharge on GIS spacer from the interferences such as corona in SF6 and surface discharge is of great interests in the evaluation of GIS health conditions. The spacer insulation deteriorates quickly when such discharges occur along small crackles on spacer surface. This paper presents two approaches to differentiate three types of discharges, i.e., corona in SF6, surface discharge and crackle discharge. The former can be distinguished from the latter two by analyzing the phase resolved partial discharge pattern. Further analysis of the decomposed gases accumulated from discharges reveals that CF4 is a useful indicator for discharge on spacer, and H2 occurs only with crackle discharge. Thus the combination of the above two measures provides powerful aids in the detection of crackle discharge in GIS.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114510846","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547768
K. Hencken, A. Abbasi
This paper investigates the necessary steps required to analyze the results of a PEA measurement. It is shown, that in a mixed frequency-space presentation it can be seen as a two-step process of deconvolution of the signal and reconstruction of the space charge using the acoustic Green's function. It is discussed how the knowledge of the expected signal can be used to improve the deconvolution and how attenuation and dispersion effects can be taken into account in an analytic approach. The techniques are finally applied to both simulated and real measurement data.
{"title":"Analysis of the deconvolution and reconstruction of PEA signals for HV insulation materials","authors":"K. Hencken, A. Abbasi","doi":"10.1109/ICD.2016.7547768","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547768","url":null,"abstract":"This paper investigates the necessary steps required to analyze the results of a PEA measurement. It is shown, that in a mixed frequency-space presentation it can be seen as a two-step process of deconvolution of the signal and reconstruction of the space charge using the acoustic Green's function. It is discussed how the knowledge of the expected signal can be used to improve the deconvolution and how attenuation and dispersion effects can be taken into account in an analytic approach. The techniques are finally applied to both simulated and real measurement data.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121909958","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547763
Yanghcun Cheng, W. Chang, J. Bi, Xiaohua Pan
The Frequency Response Analysis (FRA) method is used widely in the windings deformation diagnostics of power transformers. But until recently, the FRA method can only be used off line, because it need injecting signal into the windings. For operating transformers, it is almost impossible to inject directly the signal into the windings which are under high potential. Therefore, before applying FRA on operating transformer, the signal injection problem should be solved at first. A new signal injection method is put forward to conduct online FRA. The sweep frequency signal is injected into the neutral pinot grounding line of the windings, by the magnetic coupling of a Rogowski coil. In our laboratory, on an offline 220 kV transformer, the sweep frequency signal was injected into the bushing tap or the neutral point, and the response voltage signal and current signal on the tap or the neutral point were measured. The transfer function curves were calculated and contrasted. The results of the experiments show that injecting signal into the neutral point grounding line has the same effect as injecting voltage signal into the bushing tap. So, injecting signal from the neutral grounding line through a Rogowski coil is feasible, and the online FRA method can be used without breaking the grounding line of the bushing tap or the neutral point.
{"title":"Signal injection by magnetic coupling for the online FRA of transformer winding deformation diagnosis","authors":"Yanghcun Cheng, W. Chang, J. Bi, Xiaohua Pan","doi":"10.1109/ICD.2016.7547763","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547763","url":null,"abstract":"The Frequency Response Analysis (FRA) method is used widely in the windings deformation diagnostics of power transformers. But until recently, the FRA method can only be used off line, because it need injecting signal into the windings. For operating transformers, it is almost impossible to inject directly the signal into the windings which are under high potential. Therefore, before applying FRA on operating transformer, the signal injection problem should be solved at first. A new signal injection method is put forward to conduct online FRA. The sweep frequency signal is injected into the neutral pinot grounding line of the windings, by the magnetic coupling of a Rogowski coil. In our laboratory, on an offline 220 kV transformer, the sweep frequency signal was injected into the bushing tap or the neutral point, and the response voltage signal and current signal on the tap or the neutral point were measured. The transfer function curves were calculated and contrasted. The results of the experiments show that injecting signal into the neutral point grounding line has the same effect as injecting voltage signal into the bushing tap. So, injecting signal from the neutral grounding line through a Rogowski coil is feasible, and the online FRA method can be used without breaking the grounding line of the bushing tap or the neutral point.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122205126","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547772
Zheng Dianchun, Wei Hongqing, Zhu Bo, Li Wei, Ren Zhigang
In order to absolutely understand the microscopic process of discharge development at atmospheric pressure, the experiment of 5mm air gap discharge in the condition of rod-plate electrode is carried out, and not only the images of discharge process are recorded by intensification charge-coupled device, but also the discharge spectrum is captured. Furthermore, the hydrodynamic model is also adopted to reveal the microscopic mechanism of the 5mm air gap discharge. According to experimental results, electron temperature is estimated to be about 3.15eV. On the other hand, the simulation results show that the discharge process of the 5mm air gap could be divided into three stages: the electron avalanche stage, the streamer formation stage and streamer development stage according to the change of the peak value of the electron density.
{"title":"Research on microscopic process of 5mm air gap discharge at atmospheric pressure","authors":"Zheng Dianchun, Wei Hongqing, Zhu Bo, Li Wei, Ren Zhigang","doi":"10.1109/ICD.2016.7547772","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547772","url":null,"abstract":"In order to absolutely understand the microscopic process of discharge development at atmospheric pressure, the experiment of 5mm air gap discharge in the condition of rod-plate electrode is carried out, and not only the images of discharge process are recorded by intensification charge-coupled device, but also the discharge spectrum is captured. Furthermore, the hydrodynamic model is also adopted to reveal the microscopic mechanism of the 5mm air gap discharge. According to experimental results, electron temperature is estimated to be about 3.15eV. On the other hand, the simulation results show that the discharge process of the 5mm air gap could be divided into three stages: the electron avalanche stage, the streamer formation stage and streamer development stage according to the change of the peak value of the electron density.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122577451","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547701
P. Bokoro, I. Jandrell
The continued presence of harmonic frequencies in modern power systems raises the fundamental question of suspected aggravation of ageing or degradation process of zinc oxide (ZnO) varistors under constant operating voltage mode. In this study, the long-term effect of power system harmonics on the ageing of ZnO varistor samples is analysed on the basis of the reference or the varistor voltage and the coefficient of non-linearity, which are measured from the voltage-current charactristic (V - I). The results obtained indicate that for an increase in the total harmonic distortion (THD) from 1.5 % to 8.47 % in the continuously applied voltage, at a constant temperature of 135°C, a decrease of 66.29 % in the reference voltage, and that of 76.92 % in the coefficient of non-linearity are observed in the varistor units exposed to higher content of harmonic-distortion.
{"title":"The impact of harmonics on the V − I characteristic of ZnO varistors","authors":"P. Bokoro, I. Jandrell","doi":"10.1109/ICD.2016.7547701","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547701","url":null,"abstract":"The continued presence of harmonic frequencies in modern power systems raises the fundamental question of suspected aggravation of ageing or degradation process of zinc oxide (ZnO) varistors under constant operating voltage mode. In this study, the long-term effect of power system harmonics on the ageing of ZnO varistor samples is analysed on the basis of the reference or the varistor voltage and the coefficient of non-linearity, which are measured from the voltage-current charactristic (V - I). The results obtained indicate that for an increase in the total harmonic distortion (THD) from 1.5 % to 8.47 % in the continuously applied voltage, at a constant temperature of 135°C, a decrease of 66.29 % in the reference voltage, and that of 76.92 % in the coefficient of non-linearity are observed in the varistor units exposed to higher content of harmonic-distortion.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126233965","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547632
S. Boggs, A. Kumada, T. Yoshimitsu
The semiconductive armor tape (CAT) which covers a form wound stator bar within the slot extends beyond the slot in the end turn region to provide for connection to the nonlinear end turn stress grading (SG). At power frequency, the CAT acts as a conductor, but during PWM waveform transitions, substantial potential can drop across the CAT between the slot edge and the SG which can reduce the dissipation at the CAT-SG interface. We develop analytical approximations for grading during PWM transitions.
{"title":"Rotating machine end turn grading during PWM transitions","authors":"S. Boggs, A. Kumada, T. Yoshimitsu","doi":"10.1109/ICD.2016.7547632","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547632","url":null,"abstract":"The semiconductive armor tape (CAT) which covers a form wound stator bar within the slot extends beyond the slot in the end turn region to provide for connection to the nonlinear end turn stress grading (SG). At power frequency, the CAT acts as a conductor, but during PWM waveform transitions, substantial potential can drop across the CAT between the slot edge and the SG which can reduce the dissipation at the CAT-SG interface. We develop analytical approximations for grading during PWM transitions.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125731849","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547738
Hua Li, P. Lewin, J. Fothergill
Safety capacitors (usually denoted as X1, X2 or Y) are metallized film capacitors (MFC). Two kinds of capacitance loss mechanism typically occur in this metallized film structure: (1) caused by self-healing resulting in a very small electrode area loss; (2) caused by electrode oxidation by electrochemical corrosion under ac stress in a humid environment. This study focuses on the aging mechanism of X2 film capacitors working in high temperature and high humidity environments. Two types of X2 film capacitors have been stressed under an applied voltage of 270Vac at 85 ¼C, 78.68%RH. Capacitance and equivalent series resistance (ESR) were monitored during the experiment as parametric parameters that reflect the aging process. The aging mechanism including moisture ingress time were calculated and comprehensively analyzed with the capacitance change characteristics. It was found that capacitors with lower aluminum metallization has a better capacitance stability, the mean corrosion rate of Type2 (9.7% aluminum metallization) is more than 3 times of the Type1(6.9% aluminum metallization).The ingress time calculated by capacitance change and normalized ESR show reasonable agreement.
{"title":"Aging mechanisms of X2 metallized film capacitors in a high temperature and humidity environment","authors":"Hua Li, P. Lewin, J. Fothergill","doi":"10.1109/ICD.2016.7547738","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547738","url":null,"abstract":"Safety capacitors (usually denoted as X1, X2 or Y) are metallized film capacitors (MFC). Two kinds of capacitance loss mechanism typically occur in this metallized film structure: (1) caused by self-healing resulting in a very small electrode area loss; (2) caused by electrode oxidation by electrochemical corrosion under ac stress in a humid environment. This study focuses on the aging mechanism of X2 film capacitors working in high temperature and high humidity environments. Two types of X2 film capacitors have been stressed under an applied voltage of 270Vac at 85 ¼C, 78.68%RH. Capacitance and equivalent series resistance (ESR) were monitored during the experiment as parametric parameters that reflect the aging process. The aging mechanism including moisture ingress time were calculated and comprehensively analyzed with the capacitance change characteristics. It was found that capacitors with lower aluminum metallization has a better capacitance stability, the mean corrosion rate of Type2 (9.7% aluminum metallization) is more than 3 times of the Type1(6.9% aluminum metallization).The ingress time calculated by capacitance change and normalized ESR show reasonable agreement.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127651578","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547535
S. Diaham, F. Saysouk, M. Locatelli, T. Lebey
The impact of boron nitride (BN) nanofillers on the electrical conduction of polyimide/BN (PI/BN) nanocomposite films is investigated at high temperature from 200 to 350 °C. This paper shows that BN nanofillers largely reduce the mobility of ionic charge carriers. While neat PI exhibits space charge on the transient charging currents in this temperature range, PI/BN nanocomposites show a return to normal polarization currents. The nanostructuration of PI films enables to increase the mean free path for mobile ions by decreasing the ionic hopping distance. The consequence of the improvement of the trapping is a large decrease in the conduction current density for PI/BN nanocomposite films in a large electric field range. This study shows the possibility to extend both the electric field and temperature working ranges of PI films for HV insulation applications.
{"title":"Electrical conduction in polyimide/BN nanocomposites","authors":"S. Diaham, F. Saysouk, M. Locatelli, T. Lebey","doi":"10.1109/ICD.2016.7547535","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547535","url":null,"abstract":"The impact of boron nitride (BN) nanofillers on the electrical conduction of polyimide/BN (PI/BN) nanocomposite films is investigated at high temperature from 200 to 350 °C. This paper shows that BN nanofillers largely reduce the mobility of ionic charge carriers. While neat PI exhibits space charge on the transient charging currents in this temperature range, PI/BN nanocomposites show a return to normal polarization currents. The nanostructuration of PI films enables to increase the mean free path for mobile ions by decreasing the ionic hopping distance. The consequence of the improvement of the trapping is a large decrease in the conduction current density for PI/BN nanocomposite films in a large electric field range. This study shows the possibility to extend both the electric field and temperature working ranges of PI films for HV insulation applications.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130207331","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 : 2016-07-03DOI: 10.1109/ICD.2016.7547530
V. Belko, O. Emelyanov, I. Ivanov
Metallized film capacitors have an ability to withstand the breakdown of dielectric film due to a “self-healing” feature. The optimal design of metallized electrodes' patterns guarantees high reliability of metallized film capacitors. This paper presents the results of numerical simulation of the intersegment gate current destruction during self-healing by means of COMSOL Multiphysics software. The model takes into consideration the heat flow from metal layer to polymer film since it has significant influence on destruction process dynamics. The simulation results were shown to be in good agreement with the experimental data.
{"title":"The experimental investigation and numerical simulation of self-healing in metallized film capacitors","authors":"V. Belko, O. Emelyanov, I. Ivanov","doi":"10.1109/ICD.2016.7547530","DOIUrl":"https://doi.org/10.1109/ICD.2016.7547530","url":null,"abstract":"Metallized film capacitors have an ability to withstand the breakdown of dielectric film due to a “self-healing” feature. The optimal design of metallized electrodes' patterns guarantees high reliability of metallized film capacitors. This paper presents the results of numerical simulation of the intersegment gate current destruction during self-healing by means of COMSOL Multiphysics software. The model takes into consideration the heat flow from metal layer to polymer film since it has significant influence on destruction process dynamics. The simulation results were shown to be in good agreement with the experimental data.","PeriodicalId":306397,"journal":{"name":"2016 IEEE International Conference on Dielectrics (ICD)","volume":" 27","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113952117","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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