Pub Date : 1994-12-05DOI: 10.1109/WCPEC.1994.520029
R. Martins, E. Fortunato, A. Bicho, G. Lavareda
The aim of this work is to interpret the role of the lateral leakage current on the a-Si:H solar cell performances (J-V characteristics, responsivity and the apparent device degradation behaviour), under low illumination conditions.
{"title":"Role of the lateral leakage current on amorphous silicon solar cells","authors":"R. Martins, E. Fortunato, A. Bicho, G. Lavareda","doi":"10.1109/WCPEC.1994.520029","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.520029","url":null,"abstract":"The aim of this work is to interpret the role of the lateral leakage current on the a-Si:H solar cell performances (J-V characteristics, responsivity and the apparent device degradation behaviour), under low illumination conditions.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82157807","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 : 1994-12-05DOI: 10.1109/WCPEC.1994.519995
T. J. McMahon, M. Bennett
The transitory and erratic nature of shunt currents, whether caused by light-soaking or electrical biasing, in amorphous Si (a-Si) single- and triple-junction solar cells has been a real puzzle and made the study of these cells difficult. The authors present a careful study of the time/voltage dependence of these current transients in several different a-Si solar cell structures and find they reveal more about the basic shunt mechanism. In single-junction cells, they see stepwise current changes that increase in size and number with reverse bias and can be removed with forward bias. This stepwise, on and off switching suggests a discrete shunt path conduction mechanism. The kinetics of these metastable shunt paths show that both the "on-state" and "off-state" possess memory. Cells without (Al)ZnO show no metastable switching. The authors associate the stepwise features with the textured substrate and the switching metastability with contact to (Al)ZnO. Switching in triple-junction cells occurs with hundreds of oscillations at each step.
{"title":"Metastable shunt paths in a-Si solar cells","authors":"T. J. McMahon, M. Bennett","doi":"10.1109/WCPEC.1994.519995","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.519995","url":null,"abstract":"The transitory and erratic nature of shunt currents, whether caused by light-soaking or electrical biasing, in amorphous Si (a-Si) single- and triple-junction solar cells has been a real puzzle and made the study of these cells difficult. The authors present a careful study of the time/voltage dependence of these current transients in several different a-Si solar cell structures and find they reveal more about the basic shunt mechanism. In single-junction cells, they see stepwise current changes that increase in size and number with reverse bias and can be removed with forward bias. This stepwise, on and off switching suggests a discrete shunt path conduction mechanism. The kinetics of these metastable shunt paths show that both the \"on-state\" and \"off-state\" possess memory. Cells without (Al)ZnO show no metastable switching. The authors associate the stepwise features with the textured substrate and the switching metastability with contact to (Al)ZnO. Switching in triple-junction cells occurs with hundreds of oscillations at each step.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82208146","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 : 1994-12-05DOI: 10.1109/WCPEC.1994.520218
M. Keevers, M. Green
Sub-bandgap spectral response measurements on silicon solar cells are used to characterise the infrared response of present devices, and to investigate the impurity photovoltaic (IPV) effect for improving their infrared response. The former has, aside from establishing a baseline case, led to an improved determination of the subgap absorption coefficient of crystalline silicon. Absorption coefficient values as low as 10/sup -7/ cm/sup -1/ have been determined, revealing structure due to 3- and 4-phonon assisted absorption. The influences of free carrier absorption, bandgap narrowing, and the Franz-Keldysh effect on cell infrared response are considered. Investigation of the IPV effect of indium in high efficiency bulk and thin film cells reveals that indium improves their infrared response. The cross-section for electron photoemission from the indium level, a crucial parameter for modelling indium's IPV effect, is determined.
{"title":"Extended infrared response of silicon solar cells and the impurity photovoltaic effect","authors":"M. Keevers, M. Green","doi":"10.1109/WCPEC.1994.520218","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.520218","url":null,"abstract":"Sub-bandgap spectral response measurements on silicon solar cells are used to characterise the infrared response of present devices, and to investigate the impurity photovoltaic (IPV) effect for improving their infrared response. The former has, aside from establishing a baseline case, led to an improved determination of the subgap absorption coefficient of crystalline silicon. Absorption coefficient values as low as 10/sup -7/ cm/sup -1/ have been determined, revealing structure due to 3- and 4-phonon assisted absorption. The influences of free carrier absorption, bandgap narrowing, and the Franz-Keldysh effect on cell infrared response are considered. Investigation of the IPV effect of indium in high efficiency bulk and thin film cells reveals that indium improves their infrared response. The cross-section for electron photoemission from the indium level, a crucial parameter for modelling indium's IPV effect, is determined.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78948654","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 : 1994-12-05DOI: 10.1109/WCPEC.1994.519825
S. Niki, Y. Makita, A. Yamada, H. Shibata, P. Fons, A. Obara, T. Kurafuji, S. Chichibu, N. Nakanishi
CuInSe/sub 2/ epitaxial films with near stoichiometric compositions have been grown on GaAs (001) by molecular beam epitaxy, and radiative recombination processes in these films have been characterized by means of low temperature photoluminescence (PL) spectroscopy. Temperature dependent PL measurements on such epitaxial films have made possible the identification of conduction band to acceptor and donor-acceptor pair transitions. Well-defined emission lines were present near the bandgap, and the emissions at 1.0386 eV and at 1.0311 eV were found to be due to the ground-state free exciton and the excitons bound to neutral acceptors, respectively. The bandgap of CuInSe/sub 2/ is also determined to be E/sub g/=1.0462 eV at 2 K.
{"title":"Optical characterization of CuInSe/sub 2/ grown by molecular beam epitaxy","authors":"S. Niki, Y. Makita, A. Yamada, H. Shibata, P. Fons, A. Obara, T. Kurafuji, S. Chichibu, N. Nakanishi","doi":"10.1109/WCPEC.1994.519825","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.519825","url":null,"abstract":"CuInSe/sub 2/ epitaxial films with near stoichiometric compositions have been grown on GaAs (001) by molecular beam epitaxy, and radiative recombination processes in these films have been characterized by means of low temperature photoluminescence (PL) spectroscopy. Temperature dependent PL measurements on such epitaxial films have made possible the identification of conduction band to acceptor and donor-acceptor pair transitions. Well-defined emission lines were present near the bandgap, and the emissions at 1.0386 eV and at 1.0311 eV were found to be due to the ground-state free exciton and the excitons bound to neutral acceptors, respectively. The bandgap of CuInSe/sub 2/ is also determined to be E/sub g/=1.0462 eV at 2 K.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87453900","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 : 1994-12-05DOI: 10.1109/WCPEC.1994.519988
Yiwei Lu, Sangbo Kim, I. Chen, Yeeheng Lee, C. Fortmann, C. Wronski, R. Collins
Real time spectroscopic ellipsometry (RTSE) has been applied to characterize the p and i layers that compose amorphous silicon-based solar cells prepared in the superstrate configuration using a single-chamber reactor system. In this study, 106-point spectra (1.5-4.5 eV) in the ellipsometry angles (/spl Psi/, /spl Delta/) are obtained during solar cell preparation with acquisition and repetition times as short as 160 ms and 1 s, respectively. With the spectroscopic capability, the evolution of the microstructure can be determined, including void densities, and surface roughness and bulk layer thicknesses, the latter with submonolayer sensitivity. In addition, the complex dielectric function and optical gap of the individual layers can be determined. An ultrathin (mass thickness /spl sim/4 /spl Aring/) narrow gap interface layer is observed to form during an Ar flushing period between the growth of the p and i layers, which may reduce the open-circuit voltage and short-circuit current of the solar cell.
{"title":"Real time characterization of the preparation of amorphous silicon-based solar cells","authors":"Yiwei Lu, Sangbo Kim, I. Chen, Yeeheng Lee, C. Fortmann, C. Wronski, R. Collins","doi":"10.1109/WCPEC.1994.519988","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.519988","url":null,"abstract":"Real time spectroscopic ellipsometry (RTSE) has been applied to characterize the p and i layers that compose amorphous silicon-based solar cells prepared in the superstrate configuration using a single-chamber reactor system. In this study, 106-point spectra (1.5-4.5 eV) in the ellipsometry angles (/spl Psi/, /spl Delta/) are obtained during solar cell preparation with acquisition and repetition times as short as 160 ms and 1 s, respectively. With the spectroscopic capability, the evolution of the microstructure can be determined, including void densities, and surface roughness and bulk layer thicknesses, the latter with submonolayer sensitivity. In addition, the complex dielectric function and optical gap of the individual layers can be determined. An ultrathin (mass thickness /spl sim/4 /spl Aring/) narrow gap interface layer is observed to form during an Ar flushing period between the growth of the p and i layers, which may reduce the open-circuit voltage and short-circuit current of the solar cell.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87823725","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 : 1994-12-05DOI: 10.1109/WCPEC.1994.520730
Shotaro Saito, Yoshio Hashimoto, Kentara Ito
Heterojunction solar cells consisting of an atom beam sputtered transparent conductive window layer/chemical bath deposited CdS buffer layer/p-type InP single crystal structure were studied. A total area cell efficiency up to 17.8% was obtained at AM 1.5 and was expected to reach as high as 23% based on this structure. The buffer layer 45 to 240 nm thick plays a key role to reduce sputter damages which would be formed at the surface of InP without this layer. It was found that the the choice of window materials has an important effect on the aging properties of the cell. When ZnO is used as a window material, the fill factor of the cell was particularly degraded by aging. Using an atom beam sputtered In/sub 2/O/sub 3/ window layer, the authors have been able to obtain more reliable solar cells.
{"title":"Efficient ZnO/CdS/InP heterojunction solar cell","authors":"Shotaro Saito, Yoshio Hashimoto, Kentara Ito","doi":"10.1109/WCPEC.1994.520730","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.520730","url":null,"abstract":"Heterojunction solar cells consisting of an atom beam sputtered transparent conductive window layer/chemical bath deposited CdS buffer layer/p-type InP single crystal structure were studied. A total area cell efficiency up to 17.8% was obtained at AM 1.5 and was expected to reach as high as 23% based on this structure. The buffer layer 45 to 240 nm thick plays a key role to reduce sputter damages which would be formed at the surface of InP without this layer. It was found that the the choice of window materials has an important effect on the aging properties of the cell. When ZnO is used as a window material, the fill factor of the cell was particularly degraded by aging. Using an atom beam sputtered In/sub 2/O/sub 3/ window layer, the authors have been able to obtain more reliable solar cells.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87104231","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 : 1994-12-05DOI: 10.1109/WCPEC.1994.519977
Wei Guang-pu, Zhang Zhi-lin, Zhao Wei-ming, Gao Xiang-Hong, Chen Wei-Qun, H. Tanamura, M. Yamaguchi, H. Noguchi, T. Nagatomo, O. Omoto
Tin sulfide (SnS) solar cell semiconductor thin films were prepared by an RF sputtering method. The component, crystal structure, optical properties and electrical properties of SnS films were measured. The relationship between the SnS films properties and the sputtering condition was discussed. Using Sb as a dopant and combining thermal annealing at elevated temperatures (about 400/spl deg/C), n-type SnS homojunction solar cell thin films were obtained.
{"title":"Investigation on SnS film by RF sputtering for photovoltaic application","authors":"Wei Guang-pu, Zhang Zhi-lin, Zhao Wei-ming, Gao Xiang-Hong, Chen Wei-Qun, H. Tanamura, M. Yamaguchi, H. Noguchi, T. Nagatomo, O. Omoto","doi":"10.1109/WCPEC.1994.519977","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.519977","url":null,"abstract":"Tin sulfide (SnS) solar cell semiconductor thin films were prepared by an RF sputtering method. The component, crystal structure, optical properties and electrical properties of SnS films were measured. The relationship between the SnS films properties and the sputtering condition was discussed. Using Sb as a dopant and combining thermal annealing at elevated temperatures (about 400/spl deg/C), n-type SnS homojunction solar cell thin films were obtained.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87158624","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 : 1994-12-05DOI: 10.1109/WCPEC.1994.519856
T. Nii, I. Sugiyama, T. Kase, M. Sato, Y. Kaniyama, S. Kuriyagawa, K. Kushiya, H. Takeshita
A ZnO buffer layer by a chemical-bath deposition (CBD) method is developed in this study to improve the interface quality between the n-ZnO window layer and p-CuInSe/sub 2/ (CIS) thin-film absorber in CIS thin-film solar cells as one of the approaches to the fabrication of Cd-free thin-film solar cells. The optimization of the fabrication conditions of CBD-ZnO leads to an efficiency of about 10%. These results indicate that the CBD-ZnO buffer layer has a rather high capability to fabricate high-efficiency CIS thin-film solar cells.
{"title":"Effects of Cd-free buffer layer for CuInSe/sub 2/ thin-film solar cells","authors":"T. Nii, I. Sugiyama, T. Kase, M. Sato, Y. Kaniyama, S. Kuriyagawa, K. Kushiya, H. Takeshita","doi":"10.1109/WCPEC.1994.519856","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.519856","url":null,"abstract":"A ZnO buffer layer by a chemical-bath deposition (CBD) method is developed in this study to improve the interface quality between the n-ZnO window layer and p-CuInSe/sub 2/ (CIS) thin-film absorber in CIS thin-film solar cells as one of the approaches to the fabrication of Cd-free thin-film solar cells. The optimization of the fabrication conditions of CBD-ZnO leads to an efficiency of about 10%. These results indicate that the CBD-ZnO buffer layer has a rather high capability to fabricate high-efficiency CIS thin-film solar cells.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87562766","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 : 1994-12-05DOI: 10.1109/WCPEC.1994.519964
G. Willeke, P. Fath, E. Bucher
Details of the design of the POWER silicon solar cell as well as process sequences are given for both a high efficiency and low cost approach. The status of the technological developments is outlined. Computer-based model calculations demonstrate the far superior performance of this design with respect to conventional structures, particularly as a starting material with small diffusion lengths. Results of a ray tracing analysis of the POWER structure with respect to optimum groove angles are also presented.
{"title":"Progress on the POWER silicon solar cell concept","authors":"G. Willeke, P. Fath, E. Bucher","doi":"10.1109/WCPEC.1994.519964","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.519964","url":null,"abstract":"Details of the design of the POWER silicon solar cell as well as process sequences are given for both a high efficiency and low cost approach. The status of the technological developments is outlined. Computer-based model calculations demonstrate the far superior performance of this design with respect to conventional structures, particularly as a starting material with small diffusion lengths. Results of a ray tracing analysis of the POWER structure with respect to optimum groove angles are also presented.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88108235","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 : 1994-12-05DOI: 10.1109/WCPEC.1994.520560
L. Broman, J. Marks
Wood fuel has a high energy density, 18.3 MJ/kg dry matter, and it is combustible also in existing oil furnaces (in the range 1-15 MW) with little alteration. In principle, wood powder would be a possible fuel for small scale combustion, and the authors are in the process of developing such a furnace. During the last few months, they have constructed and tested a feeding mechanism and a combustion chamber that seem very promising. As of November 1994, they have reached 1481 K and been able to keep the temperature around 1400 K for any length of time at the time in one of their two prototype burners. A joint thermophotovoltaic (TPV) R&D program, in which they cooperate with researchers at National Renewable Energy Laboratory, Golden, CO, USA, is in the planning, aiming at cogeneration of electricity and heat from refined wood fuel.
{"title":"Development of a TPV converter for co-generation of electricity and heat from combustion of wood powder","authors":"L. Broman, J. Marks","doi":"10.1109/WCPEC.1994.520560","DOIUrl":"https://doi.org/10.1109/WCPEC.1994.520560","url":null,"abstract":"Wood fuel has a high energy density, 18.3 MJ/kg dry matter, and it is combustible also in existing oil furnaces (in the range 1-15 MW) with little alteration. In principle, wood powder would be a possible fuel for small scale combustion, and the authors are in the process of developing such a furnace. During the last few months, they have constructed and tested a feeding mechanism and a combustion chamber that seem very promising. As of November 1994, they have reached 1481 K and been able to keep the temperature around 1400 K for any length of time at the time in one of their two prototype burners. A joint thermophotovoltaic (TPV) R&D program, in which they cooperate with researchers at National Renewable Energy Laboratory, Golden, CO, USA, is in the planning, aiming at cogeneration of electricity and heat from refined wood fuel.","PeriodicalId":20517,"journal":{"name":"Proceedings of 1994 IEEE 1st World Conference on Photovoltaic Energy Conversion - WCPEC (A Joint Conference of PVSC, PVSEC and PSEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1994-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83878918","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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