Pub Date : 1991-07-08DOI: 10.1109/ICPADM.1991.172167
A. Bognár, G. Csépes, L. Kalocsai, I. Kispál
A novel test method for the assessment of the bulk dielectric properties of oil-paper insulation has been developed. Specifically, the authors describe a simple on-site DC testing and apparatus for the determination of the polarization spectrum in the polarization time-constant domain of 10/sup -3/ to 10/sup 4/ s. In this range the so-called interface polarization phenomena of long time constant are active, which are highly influenced by the water content of oil-impregnated paper insulation and the adsorption of byproducts of aging. The method can be regarded as a complementary diagnosis method of dissolved gas analysis and other analytical methods and gives information on the general state and dielectric aging of the impregnated paper insulation. The test method and apparatus have been successfully and widely used on high-voltage power transformers of the Hungarian Electricity Board.<>
{"title":"Spectrum of polarization phenomena of long time-constant as a diagnostic method of oil-paper insulating systems","authors":"A. Bognár, G. Csépes, L. Kalocsai, I. Kispál","doi":"10.1109/ICPADM.1991.172167","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172167","url":null,"abstract":"A novel test method for the assessment of the bulk dielectric properties of oil-paper insulation has been developed. Specifically, the authors describe a simple on-site DC testing and apparatus for the determination of the polarization spectrum in the polarization time-constant domain of 10/sup -3/ to 10/sup 4/ s. In this range the so-called interface polarization phenomena of long time constant are active, which are highly influenced by the water content of oil-impregnated paper insulation and the adsorption of byproducts of aging. The method can be regarded as a complementary diagnosis method of dissolved gas analysis and other analytical methods and gives information on the general state and dielectric aging of the impregnated paper insulation. The test method and apparatus have been successfully and widely used on high-voltage power transformers of the Hungarian Electricity Board.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"30 1","pages":"723-726 vol.2"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77226322","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 : 1991-07-08DOI: 10.1109/ICPADM.1991.172042
K. Imai, A. Kanematsu, M. Nawata, M. Zahn
Kerr electro-optic field mapping measurements using the sensitive AC modulation method were made in liquid nitrogen. The steady-state electric fields between parallel stainless steel electrodes that had a gap of 7 mm are shown to be essentially uniform for voltages up to 70 kV with no significant space charge distortion. The Kerr constant B of liquid nitrogen is constant over the AC modulation frequency range of 1-20 kHz, while increasing above 20 kHz. This change of B with the modulation frequency coincides with the frequency-amplitude gain characteristic of the lock-in amplifier used, so that B is independent of the AC modulation frequency within the range of this study. B monotonically decreases with increasing temperature, T, thus decreasing liquid nitrogen density, rho , so that B is related linearly to rho /T. The polarizability anisotropy of liquid nitrogen is evaluated to be 8.3*10/sup -41/ F-m/sup 2/ from the slope of the B-( rho /T) characteristic, obtained from a simple physical model.<>
{"title":"Kerr constant frequency dependence in liquid nitrogen","authors":"K. Imai, A. Kanematsu, M. Nawata, M. Zahn","doi":"10.1109/ICPADM.1991.172042","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172042","url":null,"abstract":"Kerr electro-optic field mapping measurements using the sensitive AC modulation method were made in liquid nitrogen. The steady-state electric fields between parallel stainless steel electrodes that had a gap of 7 mm are shown to be essentially uniform for voltages up to 70 kV with no significant space charge distortion. The Kerr constant B of liquid nitrogen is constant over the AC modulation frequency range of 1-20 kHz, while increasing above 20 kHz. This change of B with the modulation frequency coincides with the frequency-amplitude gain characteristic of the lock-in amplifier used, so that B is independent of the AC modulation frequency within the range of this study. B monotonically decreases with increasing temperature, T, thus decreasing liquid nitrogen density, rho , so that B is related linearly to rho /T. The polarizability anisotropy of liquid nitrogen is evaluated to be 8.3*10/sup -41/ F-m/sup 2/ from the slope of the B-( rho /T) characteristic, obtained from a simple physical model.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"322 1","pages":"280-283 vol.1"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80269078","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 : 1991-07-08DOI: 10.1109/ICPADM.1991.172237
M. Hammam, S. Ochiai, C. Burns
The influence of accumulated charges on a polymer insulated surface on the 50% lightning impulse (1.2-50 mu s) has been investigated. The 50% flashover voltage was measured for three different conditions: under dry environment, immediately after immersing the upper shed and body of the insulator in saline water, and immediately after completely immersing the insulator in saline water. The negative polarity 50% flashover voltage under the dry condition is the highest. This shows that negative charges accumulated on the air-insulator interface under the triple junction and in voids near the triple junction suppress the progress of the streamer. The 50% flashover voltage for the positive polarity case under dry conditions is lower than that for the negative case. This shows that the amount of positive charges accumulated on the insulator surface under the triple junction and in voids near the triple junction is less than that under negative polarity. It also suggests that positive charges generated around the stripped cable-insulator interface diffuse onto the shed surface more extensively.<>
{"title":"Effect on 50% flashover voltage due to accumulated charges on the surface of polymer insulators","authors":"M. Hammam, S. Ochiai, C. Burns","doi":"10.1109/ICPADM.1991.172237","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172237","url":null,"abstract":"The influence of accumulated charges on a polymer insulated surface on the 50% lightning impulse (1.2-50 mu s) has been investigated. The 50% flashover voltage was measured for three different conditions: under dry environment, immediately after immersing the upper shed and body of the insulator in saline water, and immediately after completely immersing the insulator in saline water. The negative polarity 50% flashover voltage under the dry condition is the highest. This shows that negative charges accumulated on the air-insulator interface under the triple junction and in voids near the triple junction suppress the progress of the streamer. The 50% flashover voltage for the positive polarity case under dry conditions is lower than that for the negative case. This shows that the amount of positive charges accumulated on the insulator surface under the triple junction and in voids near the triple junction is less than that under negative polarity. It also suggests that positive charges generated around the stripped cable-insulator interface diffuse onto the shed surface more extensively.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"26 1","pages":"981-984 vol.2"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83081019","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 : 1991-07-08DOI: 10.1109/ICPADM.1991.172284
M. Nagao, K. Takano, Y. Mizuno, M. Kosaki
The intrinsic AC electrical breakdown of low-density polyethylene film was studied above room temperature under the partial-discharge-free condition using McKeown-type specimens. The dependence of AC electric strength on the temperature, the rise rate, and the frequency of applied electric field suggests that, under AC voltage application, the thermal process might be dominant rather than the electronic process. The results are also discussed in terms of the dependence of the high-field dielectric dissipation factor on the applied electric field and the voltage application time.<>
{"title":"Intrinsic AC breakdown of low-density polyethylene film above room temperature","authors":"M. Nagao, K. Takano, Y. Mizuno, M. Kosaki","doi":"10.1109/ICPADM.1991.172284","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172284","url":null,"abstract":"The intrinsic AC electrical breakdown of low-density polyethylene film was studied above room temperature under the partial-discharge-free condition using McKeown-type specimens. The dependence of AC electric strength on the temperature, the rise rate, and the frequency of applied electric field suggests that, under AC voltage application, the thermal process might be dominant rather than the electronic process. The results are also discussed in terms of the dependence of the high-field dielectric dissipation factor on the applied electric field and the voltage application time.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"34 1","pages":"1165-1168 vol.2"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86498148","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 : 1991-07-08DOI: 10.1109/ICPADM.1991.172029
M. Fukuzawa, I. Mitsumasa
The authors measured the TSC (thermally stimulated current) and TSSP (thermally stimulated surface potential) on low-density polyethylene (LDPE) films sandwiched between needle electrodes and plane electrodes, and then evaluated the space charges. To confirm that injection occurs from needle electrodes and that injection space charges are trapped around the needle tips, the experiments were carried out with different numbers of needle electrodes, e.g. 20. Finally, the authors examined the influence of the space charges on the mechanisms of treeing in an LDPE film by measuring the inception voltage of treeing in the film.<>
{"title":"Thermally stimulated electrical measurement of an LDPE film stressed under a nonuniform electric field: influence of the space charge on treeing","authors":"M. Fukuzawa, I. Mitsumasa","doi":"10.1109/ICPADM.1991.172029","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172029","url":null,"abstract":"The authors measured the TSC (thermally stimulated current) and TSSP (thermally stimulated surface potential) on low-density polyethylene (LDPE) films sandwiched between needle electrodes and plane electrodes, and then evaluated the space charges. To confirm that injection occurs from needle electrodes and that injection space charges are trapped around the needle tips, the experiments were carried out with different numbers of needle electrodes, e.g. 20. Finally, the authors examined the influence of the space charges on the mechanisms of treeing in an LDPE film by measuring the inception voltage of treeing in the film.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"26 1","pages":"121-126 vol.1"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88815173","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 : 1991-07-08DOI: 10.1109/ICPADM.1991.172208
S. Ochiai, H. Iwasaki, M. Ieda, T. Mizutani
The electrical properties and oil/polymer interaction for an alkylbenzene/polypropylene (PP) composite insulator with chemically etched polymer (PPc) were investigated with the thermally stimulated current (TSC), surface roughness, and FT-IR (Fourier transform infrared) methods. The etched rough surface was obtained by the dissolution of the amorphous part of the PP surface in sulfuric acid. The TSC obtained on an oil/PPc specimen has four clear peaks. The comparison in TSC between oil/PP (virgin) and oil/PPc revealed that impurities in PP exist near the surface of PP and that PPc has shallower ion traps than PP. It is concluded that the wettability of the polymer surface was improved by the chemical etching. In other words, the chemical etching of the polymer surface produces an optimum polymer surface for the impregnation of oil.<>
{"title":"TSC of oil/polymer film composite insulator with chemically etched polymer film","authors":"S. Ochiai, H. Iwasaki, M. Ieda, T. Mizutani","doi":"10.1109/ICPADM.1991.172208","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172208","url":null,"abstract":"The electrical properties and oil/polymer interaction for an alkylbenzene/polypropylene (PP) composite insulator with chemically etched polymer (PPc) were investigated with the thermally stimulated current (TSC), surface roughness, and FT-IR (Fourier transform infrared) methods. The etched rough surface was obtained by the dissolution of the amorphous part of the PP surface in sulfuric acid. The TSC obtained on an oil/PPc specimen has four clear peaks. The comparison in TSC between oil/PP (virgin) and oil/PPc revealed that impurities in PP exist near the surface of PP and that PPc has shallower ion traps than PP. It is concluded that the wettability of the polymer surface was improved by the chemical etching. In other words, the chemical etching of the polymer surface produces an optimum polymer surface for the impregnation of oil.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"26 1","pages":"875-878 vol.2"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89412859","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 : 1991-07-08DOI: 10.1109/ICPADM.1991.172129
M. Ieda, H. Karner, Y. Suzuoka
The authors summarize interfacial phenomena involved mainly in solid insulating systems. Emphasis is placed on charge injection and accumulation, electrochemical reaction, carrier transport, carrier trapping, mechanical stress, swelling, and streaming electrification. It is pointed out that various kinds of interfacial effects manifest themselves in various ways in affect the electrical properties of composites. The discussion is limited to interfaces inside solids or solid-liquid composites.<>
{"title":"Fundamental aspects of interfacial phenomena in solid insulating systems","authors":"M. Ieda, H. Karner, Y. Suzuoka","doi":"10.1109/ICPADM.1991.172129","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172129","url":null,"abstract":"The authors summarize interfacial phenomena involved mainly in solid insulating systems. Emphasis is placed on charge injection and accumulation, electrochemical reaction, carrier transport, carrier trapping, mechanical stress, swelling, and streaming electrification. It is pointed out that various kinds of interfacial effects manifest themselves in various ways in affect the electrical properties of composites. The discussion is limited to interfaces inside solids or solid-liquid composites.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"19 1","pages":"598-603 vol.1"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88808752","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 : 1991-07-08DOI: 10.1109/ICPADM.1991.172039
K. Kojima, A. Maeda, M. Ieda
Electroluminescence and electrical conduction in TCNQ (tetracyanoquinodimethane) thin films prepared by the vacuum-evaporation technique were investigated. The electrical properties depended strongly on the thin film deposition conditions, such as deposition rate and/or temperature and substrate temperature. The conduction currents were also affected by the electrode materials. Higher conductivity was observed in the specimen with a Cu anode than in that with Au or Al. The thermally stimulated current showed two peaks, at -120 and -20 degrees C. The trap depths were estimated as 0.10 and 0.22 eV, respectively. X-ray diffraction studies showed that the specimen prepared at 280 degrees C was crystalline, but the one prepared at 180 degrees C was amorphous. An infrared absorption analysis showed that the main chemical composition of TCNQ has been largely preserved in the vacuum-evaporated films.<>
{"title":"Electrical properties of TCNQ evaporated thin films","authors":"K. Kojima, A. Maeda, M. Ieda","doi":"10.1109/ICPADM.1991.172039","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172039","url":null,"abstract":"Electroluminescence and electrical conduction in TCNQ (tetracyanoquinodimethane) thin films prepared by the vacuum-evaporation technique were investigated. The electrical properties depended strongly on the thin film deposition conditions, such as deposition rate and/or temperature and substrate temperature. The conduction currents were also affected by the electrode materials. Higher conductivity was observed in the specimen with a Cu anode than in that with Au or Al. The thermally stimulated current showed two peaks, at -120 and -20 degrees C. The trap depths were estimated as 0.10 and 0.22 eV, respectively. X-ray diffraction studies showed that the specimen prepared at 280 degrees C was crystalline, but the one prepared at 180 degrees C was amorphous. An infrared absorption analysis showed that the main chemical composition of TCNQ has been largely preserved in the vacuum-evaporated films.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"25 1","pages":"185-188 vol.1"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84003404","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 : 1991-07-08DOI: 10.1109/ICPADM.1991.172048
C. Mazzetti, M. Pompili, E. Forster
Some studies have suggested that there may exist a relationship between conduction and electrical breakdown. Before such a correlation between these phenomena and partial discharges (PDs) can be investigated, it is necessary to produce reproducible PD data. For this reason an investigation was undertaken to study the behavior of some well-defined dielectric fluids such as phenyl xylene ethane, ditolyl ether, mono and dibenzyl toluene, and perfluoro polyether in the pure state. Some preliminary results of this study are presented, and their significance is discussed in detail.<>
{"title":"Electric conduction breakdown and partial discharges in dielectric fluids. I. Partial discharges","authors":"C. Mazzetti, M. Pompili, E. Forster","doi":"10.1109/ICPADM.1991.172048","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172048","url":null,"abstract":"Some studies have suggested that there may exist a relationship between conduction and electrical breakdown. Before such a correlation between these phenomena and partial discharges (PDs) can be investigated, it is necessary to produce reproducible PD data. For this reason an investigation was undertaken to study the behavior of some well-defined dielectric fluids such as phenyl xylene ethane, ditolyl ether, mono and dibenzyl toluene, and perfluoro polyether in the pure state. Some preliminary results of this study are presented, and their significance is discussed in detail.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"45 9 1","pages":"261-263 vol.1"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82742734","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 : 1991-07-08DOI: 10.1109/ICPADM.1991.172352
S. Bamji, A. Bulinski, Y. Chen, R. Densley
A mechanism of degradation in polymeric insulation at fields lower than required for hot-electron transport is shown. Cable grade low-density polyethylene was aged under divergent and uniform fields, using needle-plane and dimple-plane geometries, respectively. It is shown that, at points of electric stress enhancement in the polymer, the light emitted during the initiation phase of electrical treeing is not due to hot-electron impact but is due to the recombination of electrons and holes injected into the material. The spectra of the emitted light are in the visible and ultraviolet ranges. The ultraviolet light can photodegrade the polymer and lead to electrical treeing. Long-term aging of polyethylene, under divergent and uniform fields, indicates that treeing does not occur at fields below the light inception level. However, above this level an electrical tree always develops and the time to treeing depends on the voltage applied to the polymer.<>
{"title":"Photodegradation versus hot-electron impact for electrical tree inception at low electric fields","authors":"S. Bamji, A. Bulinski, Y. Chen, R. Densley","doi":"10.1109/ICPADM.1991.172352","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172352","url":null,"abstract":"A mechanism of degradation in polymeric insulation at fields lower than required for hot-electron transport is shown. Cable grade low-density polyethylene was aged under divergent and uniform fields, using needle-plane and dimple-plane geometries, respectively. It is shown that, at points of electric stress enhancement in the polymer, the light emitted during the initiation phase of electrical treeing is not due to hot-electron impact but is due to the recombination of electrons and holes injected into the material. The spectra of the emitted light are in the visible and ultraviolet ranges. The ultraviolet light can photodegrade the polymer and lead to electrical treeing. Long-term aging of polyethylene, under divergent and uniform fields, indicates that treeing does not occur at fields below the light inception level. However, above this level an electrical tree always develops and the time to treeing depends on the voltage applied to the polymer.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"1 1","pages":"51-54 vol.1"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82965759","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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