Pub Date : 1991-07-08DOI: 10.1109/ICPADM.1991.172096
Chen Kuan, Liu De-kuan, Wang Xin, Xia Tong-Jia
The hot-ageing of electrical insulating paper made of oxygen-alkali (O-A) kenaf bast fibre was investigated. After hot kinetic stress, the mechanical strength of the kenaf bast fibre decreases somewhat, but the electrical properties do not change throughout the whole process. Either in air or in a transformer, the kenaf bast fibre electric insulating paper and press board's deterioration rate of the hot-ageing property is similar to that of NUKP electric insulating paper and press board. Because the initial value of this property is greater for the kenaf bast fibre pulp, its absolute value after ageing is also greater.<>
{"title":"The hot-ageing property of electric insulating paper and press board of O-A kenaf bast fibre","authors":"Chen Kuan, Liu De-kuan, Wang Xin, Xia Tong-Jia","doi":"10.1109/ICPADM.1991.172096","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172096","url":null,"abstract":"The hot-ageing of electrical insulating paper made of oxygen-alkali (O-A) kenaf bast fibre was investigated. After hot kinetic stress, the mechanical strength of the kenaf bast fibre decreases somewhat, but the electrical properties do not change throughout the whole process. Either in air or in a transformer, the kenaf bast fibre electric insulating paper and press board's deterioration rate of the hot-ageing property is similar to that of NUKP electric insulating paper and press board. Because the initial value of this property is greater for the kenaf bast fibre pulp, its absolute value after ageing is also greater.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"106 1","pages":"458-461 vol.1"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85259305","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.1991.172188
Jae-Hyung Lee, K. Lim, K. Chung, Boen-Heup Kim, Myungsung Kang
Copper-ion conducting glasses were prepared in the system (CuI,CuCl)-Cu/sub 2/O-MoO/sub 3/ using a rapid quenching technique. These glasses have high ionic conductivities at room temperature in the range of 10/sup -4/ to 10/sup -2/ S-m/sup -1/, and the conductivities increase with increasing CuI content but decrease with increasing CuCl content. The increase in the conductivity can be explained in terms of a decrease in the activation energy for conduction, and the activation energies for conduction are 0.19-0.39 eV. The electronic conductivities were measured by the Wagner polarization method. The ion transport numbers are 0.995-0.997, and it is shown that the transport number of Cu/sup +/ ions in these glasses is practically unity. The dielectric relaxation time is in the range of 3.7*10/sup -4/ to 1.2*10/sup -3/ s. The activation energies for ion jumping are 0.18-0.36 eV, and these are similar to those for conduction.<>
{"title":"Electrical properties of the glasses in the system (CuI,CuCl)-Cu/sub 2/O-MoO/sub 3/","authors":"Jae-Hyung Lee, K. Lim, K. Chung, Boen-Heup Kim, Myungsung Kang","doi":"10.1109/ICPADM.1991.172188","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172188","url":null,"abstract":"Copper-ion conducting glasses were prepared in the system (CuI,CuCl)-Cu/sub 2/O-MoO/sub 3/ using a rapid quenching technique. These glasses have high ionic conductivities at room temperature in the range of 10/sup -4/ to 10/sup -2/ S-m/sup -1/, and the conductivities increase with increasing CuI content but decrease with increasing CuCl content. The increase in the conductivity can be explained in terms of a decrease in the activation energy for conduction, and the activation energies for conduction are 0.19-0.39 eV. The electronic conductivities were measured by the Wagner polarization method. The ion transport numbers are 0.995-0.997, and it is shown that the transport number of Cu/sup +/ ions in these glasses is practically unity. The dielectric relaxation time is in the range of 3.7*10/sup -4/ to 1.2*10/sup -3/ s. The activation energies for ion jumping are 0.18-0.36 eV, and these are similar to those for conduction.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"46 1","pages":"160-163 vol.1"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85284662","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.1991.172194
A. Kojima, S. Sato, N. Iijima, M. Sone, H. Mitsui
A micro-channel plate (MCP) was used to measure the minute emission current within the range of 1*10/sup -19/ A to 1*10/sup -14/ A in a high vacuum (1.3*10/sup -5/ Pa). By a Fowler-Nordheim plot, it is found that the effective field strength for initial electron emission is mostly constant between 10/sup 7/ and 10/sup 8/ V/cm under any gap length. The effective field strength is held constant between 10/sup 7/ and 10/sup 8/ V/cm, independent of the current under any gap length. With this result, a model which shows the choice of minute projection is suggested. In order to certify this model, an MCP phosphor-anode is used. As a result, it is found that the minute projections which emit electrons melt with heat and are chosen when the voltage rises.<>
{"title":"Effect of gap length on effective field strength","authors":"A. Kojima, S. Sato, N. Iijima, M. Sone, H. Mitsui","doi":"10.1109/ICPADM.1991.172194","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172194","url":null,"abstract":"A micro-channel plate (MCP) was used to measure the minute emission current within the range of 1*10/sup -19/ A to 1*10/sup -14/ A in a high vacuum (1.3*10/sup -5/ Pa). By a Fowler-Nordheim plot, it is found that the effective field strength for initial electron emission is mostly constant between 10/sup 7/ and 10/sup 8/ V/cm under any gap length. The effective field strength is held constant between 10/sup 7/ and 10/sup 8/ V/cm, independent of the current under any gap length. With this result, a model which shows the choice of minute projection is suggested. In order to certify this model, an MCP phosphor-anode is used. As a result, it is found that the minute projections which emit electrons melt with heat and are chosen when the voltage rises.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"14 1","pages":"824-827 vol.2"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85363787","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.1991.172088
Y. Kito, N. Hayakawa, T. Sakai, H. Okubo
When a large amount of electric power is directly supplied through superconducting power cables from a satellite power plant to a future computer-based city center, they can be operated under lightning-surge-free circumstances. The insulation thickness necessary to withstand a lightning surge is left out of the consideration of such a condition. The authors point out that the reduction of insulation thickness is very effective in helping decrease not only the AC loss, but also the total transmission loss in the superconducting cable. Quantitative investigations are carried out with respect to a liquid-nitrogen-cooled high-T/sub c/ superconducting cable. A reduction of 20-30% of the insulation thickness is shown to result in a decrease of 15% of the total loss for a 3000-MVA, 275-kV cable. For a transmission capacity of 5000 MVA the reduction rate of the total transmission loss of a 275-kV superconducting cable is 35%.<>
{"title":"Reduction of insulation thickness and AC loss in a superconducting cable under lightning-surge-free circumstances","authors":"Y. Kito, N. Hayakawa, T. Sakai, H. Okubo","doi":"10.1109/ICPADM.1991.172088","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172088","url":null,"abstract":"When a large amount of electric power is directly supplied through superconducting power cables from a satellite power plant to a future computer-based city center, they can be operated under lightning-surge-free circumstances. The insulation thickness necessary to withstand a lightning surge is left out of the consideration of such a condition. The authors point out that the reduction of insulation thickness is very effective in helping decrease not only the AC loss, but also the total transmission loss in the superconducting cable. Quantitative investigations are carried out with respect to a liquid-nitrogen-cooled high-T/sub c/ superconducting cable. A reduction of 20-30% of the insulation thickness is shown to result in a decrease of 15% of the total loss for a 3000-MVA, 275-kV cable. For a transmission capacity of 5000 MVA the reduction rate of the total transmission loss of a 275-kV superconducting cable is 35%.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"18 1","pages":"426-429 vol.1"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85386601","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.1991.172198
A. Bolozdynya
It is experimentally shown that transport of hot quasifree electrons through an interface of condensed krypton in the gas phase has a threshold character in a stationary electric field E. Near the triple point the emission probability is on the order of 1 at E>E/sub o/ and <1% at E>
{"title":"Transport of excess electrons through and along a condensed krypton interface","authors":"A. Bolozdynya","doi":"10.1109/ICPADM.1991.172198","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172198","url":null,"abstract":"It is experimentally shown that transport of hot quasifree electrons through an interface of condensed krypton in the gas phase has a threshold character in a stationary electric field E. Near the triple point the emission probability is on the order of 1 at E>E/sub o/ and <1% at E<E/sub o/, where E/sub o/=1600 and 980 V/cm in liquid and solid K/sub r/, respectively. At E<E/sub o/, unemitted electrons localize under the interface in the normal direction and they keep a quasifree state in the tangential plane.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"58 2 Suppl 1 1","pages":"841-844 vol.2"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77753830","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.1991.172212
V. Arakelyan, L.A. Daryan, A. Lokhanin
Results of an experimental investigation of gas formation due to the decomposition of some insulating liquids under the stress of PD (partial discharges), heat, and ultrasonics are given. The investigation was performed on a special device providing full analysis of gaseous decomposition products. This device excludes losses of the gases formed, allows the possibility of liquid mixing and provides for the insulating liquid test for chromatographic analysis. It is proposed that the method of ultrasonic stress be used for primary evaluation of insulating liquids for their application in high-voltage capacitors.<>
{"title":"Gas formation in insulating liquids under the stress of partial discharges, heat and ultrasonics; diagnostics of their behavior","authors":"V. Arakelyan, L.A. Daryan, A. Lokhanin","doi":"10.1109/ICPADM.1991.172212","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172212","url":null,"abstract":"Results of an experimental investigation of gas formation due to the decomposition of some insulating liquids under the stress of PD (partial discharges), heat, and ultrasonics are given. The investigation was performed on a special device providing full analysis of gaseous decomposition products. This device excludes losses of the gases formed, allows the possibility of liquid mixing and provides for the insulating liquid test for chromatographic analysis. It is proposed that the method of ultrasonic stress be used for primary evaluation of insulating liquids for their application in high-voltage capacitors.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"310 1","pages":"890-893 vol.2"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76349426","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.1991.172243
K. Iida, S. Nakamura, G. Sawa
The electrical conduction of various kinds of polyethylene (PE) has been studied above its melting point. PEs were characterized by the amount and types of branches, double bonds, and oxygen-containing groups. Two components of the conduction currents were found; one obeyed Ohm's law in the low field range while the other was proportional to the square of the field at lower temperatures in the high field range, and was also inversely proportional to sample thickness at a constant field. The conduction mechanism of the latter component is ascribed to space-charge-limited current (SCLC). Among the features of PE molecular structures, only the oxygen-containing groups were well correlated with the SCLC. In fact, the oxygen-containing groups reduced the SCLC, suggesting that they act as traps even in the molten state. Branches and double bonds are known to act as traps in the solid state, but they bore no consistent relation to the electrical conduction in the molten state.<>
{"title":"Effects of molecular structure on electrical conduction in molten polyethylene","authors":"K. Iida, S. Nakamura, G. Sawa","doi":"10.1109/ICPADM.1991.172243","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172243","url":null,"abstract":"The electrical conduction of various kinds of polyethylene (PE) has been studied above its melting point. PEs were characterized by the amount and types of branches, double bonds, and oxygen-containing groups. Two components of the conduction currents were found; one obeyed Ohm's law in the low field range while the other was proportional to the square of the field at lower temperatures in the high field range, and was also inversely proportional to sample thickness at a constant field. The conduction mechanism of the latter component is ascribed to space-charge-limited current (SCLC). Among the features of PE molecular structures, only the oxygen-containing groups were well correlated with the SCLC. In fact, the oxygen-containing groups reduced the SCLC, suggesting that they act as traps even in the molten state. Branches and double bonds are known to act as traps in the solid state, but they bore no consistent relation to the electrical conduction in the molten state.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"71 1","pages":"1007-1010 vol.2"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81403535","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.1991.172347
M. Matsudo, T. Saito, Y. Ehara, O. Kishida, T. Ito
An experiment was carried out to diagnose the deterioration of PMMA insulation with a needle void by analyzing partial discharge and the discharge luminescence. It was shown that, by using image analysis of the discharge luminescence, the state of the discharge could be minutely observed. At the early and the intermediate stages of the deterioration, a swarming pulsed microdischarge occurred. After the occurrence of the tree, the discharge magnitude and the number of pulses are rapidly increased, and the correlation of the discharge luminescence and the maximum discharge magnitude is marked.<>
{"title":"Relationships between partial discharge magnitude and discharge luminescence of insulation","authors":"M. Matsudo, T. Saito, Y. Ehara, O. Kishida, T. Ito","doi":"10.1109/ICPADM.1991.172347","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172347","url":null,"abstract":"An experiment was carried out to diagnose the deterioration of PMMA insulation with a needle void by analyzing partial discharge and the discharge luminescence. It was shown that, by using image analysis of the discharge luminescence, the state of the discharge could be minutely observed. At the early and the intermediate stages of the deterioration, a swarming pulsed microdischarge occurred. After the occurrence of the tree, the discharge magnitude and the number of pulses are rapidly increased, and the correlation of the discharge luminescence and the maximum discharge magnitude is marked.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"1 1","pages":"31-34 vol.1"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90046022","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.1991.172296
Ying Li, M. Yasuda, T. Takada
The pulsed electroacoustic method was used to analyze the influence of cross-linking agent residues on the spatial charge distribution in XLPE (cross-linked polyethylene) plates. With the change of the content of residues in samples, one can determine the following. Heterocharges dominate in the charge distribution when the content of residues is high. Homocharges dominate in the charge distribution when the content of residues is low. Heterocharges and homocharges alternately dominate in the charge distribution when the content of residue is not very high and not very low, respectively. Heterocharge distribution is due to the movement of residues in the sample, and homocharge distribution is due to the injection of electrons and holes from the cathode and anode. Electron injection from the cathode is easier than hole injection from the anode.<>
{"title":"Influence on spatial charge distribution of cross-linking agent residues in XLPE","authors":"Ying Li, M. Yasuda, T. Takada","doi":"10.1109/ICPADM.1991.172296","DOIUrl":"https://doi.org/10.1109/ICPADM.1991.172296","url":null,"abstract":"The pulsed electroacoustic method was used to analyze the influence of cross-linking agent residues on the spatial charge distribution in XLPE (cross-linked polyethylene) plates. With the change of the content of residues in samples, one can determine the following. Heterocharges dominate in the charge distribution when the content of residues is high. Homocharges dominate in the charge distribution when the content of residues is low. Heterocharges and homocharges alternately dominate in the charge distribution when the content of residue is not very high and not very low, respectively. Heterocharge distribution is due to the movement of residues in the sample, and homocharge distribution is due to the injection of electrons and holes from the cathode and anode. Electron injection from the cathode is easier than hole injection from the anode.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"1 1","pages":"1210-1213 vol.2"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89729532","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}
The influence of uniaxial and biaxial orientation on polarization phenomena of polyethylene terephthalate (PET) films has been investigated. Thermally stimulated current (TSC) spectroscopy has been applied to the study of the kinetics of polarization phenomena in unoriented and in uniaxially and biaxially oriented PET films. Around 50 degrees C, a relaxation mode that seems to be a precursor of the glass transition is observed. This sub-T/sub g/ mode has been attributed to free volume diffusion. Around the glass transition temperature (T/sub g/) a relaxation mode is observed in all samples: in unoriented PET, it is located at 82 degrees C, while in uniaxially oriented PET, is is shifted to 85 degrees C, and in biaxially oriented PET, it reaches 100 degrees C. These complex relaxation modes have been analyzed by using the technique of fractional polarizations, and the kinetics of the elementary depolarizations has been characterized by activation enthalpies and entropies. Around the crystallization temperature, a spontaneous TSC peak due to pyrocurrent is observed in unoriented and uniaxially oriented PET. It has been associated with the dielectric manifestation of the crystallization.<>
{"title":"Influence of molecular orientation on polarization phenomena in polyethylene terephthalate films","authors":"A. Bernès, D. Chatain, C. Lacabanne","doi":"10.1109/14.142708","DOIUrl":"https://doi.org/10.1109/14.142708","url":null,"abstract":"The influence of uniaxial and biaxial orientation on polarization phenomena of polyethylene terephthalate (PET) films has been investigated. Thermally stimulated current (TSC) spectroscopy has been applied to the study of the kinetics of polarization phenomena in unoriented and in uniaxially and biaxially oriented PET films. Around 50 degrees C, a relaxation mode that seems to be a precursor of the glass transition is observed. This sub-T/sub g/ mode has been attributed to free volume diffusion. Around the glass transition temperature (T/sub g/) a relaxation mode is observed in all samples: in unoriented PET, it is located at 82 degrees C, while in uniaxially oriented PET, is is shifted to 85 degrees C, and in biaxially oriented PET, it reaches 100 degrees C. These complex relaxation modes have been analyzed by using the technique of fractional polarizations, and the kinetics of the elementary depolarizations has been characterized by activation enthalpies and entropies. Around the crystallization temperature, a spontaneous TSC peak due to pyrocurrent is observed in unoriented and uniaxially oriented PET. It has been associated with the dielectric manifestation of the crystallization.<<ETX>>","PeriodicalId":6450,"journal":{"name":"[1991] Proceedings of the 3rd International Conference on Properties and Applications of Dielectric Materials","volume":"71 1","pages":"800-803 vol.2"},"PeriodicalIF":0.0,"publicationDate":"1991-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89801962","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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