Pub Date : 2020-06-14DOI: 10.1109/PVSC45281.2020.9300979
Niranjan Kumar, A. R. Shaik, T. Walker, T. Nietzold, B. Lai, E. Colegrove, M. Stuckelberger, M. Bertoni
For decades, copper has been used to improve the performance of cadmium telluride thin film solar cells. However, it has also been shown to be the main cause of metastability in CdTe. Recently a low activation energy has been reported for the thermal diffusion of Cu in CdTe explaining the ease of motion that it has under moderate temperatures. The community consensus is that copper segregates to the absorber grain boundaries, where it's either beneficial or detrimental to device performance depending on its concentration. Using nanoscale X-ray micrsocopy and a two-dimensional drift-diffusion model we present a preliminary correlation between local copper distribution and electrical performance of a single-junction CdTe/CdS solar cell.
{"title":"Mapping Current Collection in Cross Section: The case of Copper- doped CdTe Solar Cells","authors":"Niranjan Kumar, A. R. Shaik, T. Walker, T. Nietzold, B. Lai, E. Colegrove, M. Stuckelberger, M. Bertoni","doi":"10.1109/PVSC45281.2020.9300979","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300979","url":null,"abstract":"For decades, copper has been used to improve the performance of cadmium telluride thin film solar cells. However, it has also been shown to be the main cause of metastability in CdTe. Recently a low activation energy has been reported for the thermal diffusion of Cu in CdTe explaining the ease of motion that it has under moderate temperatures. The community consensus is that copper segregates to the absorber grain boundaries, where it's either beneficial or detrimental to device performance depending on its concentration. Using nanoscale X-ray micrsocopy and a two-dimensional drift-diffusion model we present a preliminary correlation between local copper distribution and electrical performance of a single-junction CdTe/CdS solar cell.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85801725","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 : 2020-06-14DOI: 10.1109/PVSC45281.2020.9300483
O. Gunawan, S. Pae, Douglas M. Bishop, B. Shin, Yudistira Virgus, D. Mitzi
Majority and minority carrier properties such as type, density and mobility represent fundamental yet difficult to access parameters governing semiconductor device performance, most notably solar cells. Obtaining this information simultaneously under light illumination would unlock many critical parameters such as recombination lifetime, recombination coefficient, and diffusion length; while deeply interesting for optoelectronic devices, this goal has remained elusive. We demonstrate here a new carrier-resolved photo-Hall technique that rests on a new equation relating hole-electron mobility difference ($Deltamu$), Hall coefficient ($H$), and conductivity ($sigma$), and a rotating parallel dipole line ac-field Hall system with Fourier/lock-in detection for clean Hall signal measurement [1]. We successfully apply this technique to recent world-record-quality perovskite film and map the results against varying light intensities, demonstrating unprecedented simultaneous access to the above-mentioned parameters.
{"title":"Carrier-Resolved Photo-Hall Effect: Unlocking a 140-year-old secret in Hall effect","authors":"O. Gunawan, S. Pae, Douglas M. Bishop, B. Shin, Yudistira Virgus, D. Mitzi","doi":"10.1109/PVSC45281.2020.9300483","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300483","url":null,"abstract":"Majority and minority carrier properties such as type, density and mobility represent fundamental yet difficult to access parameters governing semiconductor device performance, most notably solar cells. Obtaining this information simultaneously under light illumination would unlock many critical parameters such as recombination lifetime, recombination coefficient, and diffusion length; while deeply interesting for optoelectronic devices, this goal has remained elusive. We demonstrate here a new carrier-resolved photo-Hall technique that rests on a new equation relating hole-electron mobility difference ($Deltamu$), Hall coefficient ($H$), and conductivity ($sigma$), and a rotating parallel dipole line ac-field Hall system with Fourier/lock-in detection for clean Hall signal measurement [1]. We successfully apply this technique to recent world-record-quality perovskite film and map the results against varying light intensities, demonstrating unprecedented simultaneous access to the above-mentioned parameters.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85837584","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 : 2020-06-14DOI: 10.1109/PVSC45281.2020.9300996
M. Drees, C. Stender, R. Chan, M. Osowski, N. Pan
MicroLink has developed highly flexible solar sheets that exhibit high specific power and are suitable for stratospheric flight applications. Here we present reliability test data as well as actual stratospheric flight data of these solar sheets. Data from the 24-hour high-altitude balloon flight that was performed in September 2019 out of Baltic, SD at an altitude of 19km showed peak power output of 421W/m2 of MicroLink's panel at an operating temperature of 24°C. This translates into a specific power of the solar sheets of 1,668 W/kg including top sheet and adhesive layers.
{"title":"Highly Flexible Solar Sheets With High Specific Power for Stratospheric Flight Applications","authors":"M. Drees, C. Stender, R. Chan, M. Osowski, N. Pan","doi":"10.1109/PVSC45281.2020.9300996","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300996","url":null,"abstract":"MicroLink has developed highly flexible solar sheets that exhibit high specific power and are suitable for stratospheric flight applications. Here we present reliability test data as well as actual stratospheric flight data of these solar sheets. Data from the 24-hour high-altitude balloon flight that was performed in September 2019 out of Baltic, SD at an altitude of 19km showed peak power output of 421W/m2 of MicroLink's panel at an operating temperature of 24°C. This translates into a specific power of the solar sheets of 1,668 W/kg including top sheet and adhesive layers.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84185408","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 : 2020-06-14DOI: 10.1109/PVSC45281.2020.9300860
J. T. D. de Guzman, V. Markevich, S. Hammersley, I. Hawkins, I. Crowe, N. Abrosimov, R. Falster, J. Binns, P. Altermatt, M. Halsall, A. Peaker
Minority carrier traps in Czochralski-grown (Cz) silicon crystals doped with either boron, aluminum, gallium, or indium impurity atoms have been investigated by means of deep-level transient spectroscopy and other junction-related techniques. The experimental data have suggested that minority carrier trapping effects in Cz-Si samples doped with different acceptor impurities are associated with complexes incorporating a substitutional group-III impurity atom and two oxygen atoms, which are found to be negative-U defects with close locations of E(-/+) occupancy level at about Eu + 0.32 eV. We have determined the energy barriers and frequency factors for the reversible transformations of the complexes between deep donor and shallow acceptor states. These parameters are discussed in relation to light-induced degradation behavior of solar cells on p-type Cz-Si crystals.
{"title":"Minority carrier traps in Czochralski-grown p-type silicon crystals doped with B, Al, Ga, or In impurity atoms","authors":"J. T. D. de Guzman, V. Markevich, S. Hammersley, I. Hawkins, I. Crowe, N. Abrosimov, R. Falster, J. Binns, P. Altermatt, M. Halsall, A. Peaker","doi":"10.1109/PVSC45281.2020.9300860","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300860","url":null,"abstract":"Minority carrier traps in Czochralski-grown (Cz) silicon crystals doped with either boron, aluminum, gallium, or indium impurity atoms have been investigated by means of deep-level transient spectroscopy and other junction-related techniques. The experimental data have suggested that minority carrier trapping effects in Cz-Si samples doped with different acceptor impurities are associated with complexes incorporating a substitutional group-III impurity atom and two oxygen atoms, which are found to be negative-U defects with close locations of E(-/+) occupancy level at about Eu + 0.32 eV. We have determined the energy barriers and frequency factors for the reversible transformations of the complexes between deep donor and shallow acceptor states. These parameters are discussed in relation to light-induced degradation behavior of solar cells on p-type Cz-Si crystals.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77912601","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 : 2020-06-14DOI: 10.1109/PVSC45281.2020.9300480
M. Springer, N. Bosco
This paper presents our continued work on developing a degradation model for electrically conductive adhesive (ECA) interconnects in photovoltaic modules. Here, we characterize the fracture mechanics properties of an epoxy based ECA, for both critical and subcritical loading conditions. Emphasis is put on the influence of different environmental conditions such as temperature and humidity. We found that high levels of humidity not only weaken the adhesive joint but also promote subcritical debonding at significantly lower driving forces than in dry environments.
{"title":"Environmental Influence on Fracture and Delamination of Electrically Conductive Adhesives","authors":"M. Springer, N. Bosco","doi":"10.1109/PVSC45281.2020.9300480","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300480","url":null,"abstract":"This paper presents our continued work on developing a degradation model for electrically conductive adhesive (ECA) interconnects in photovoltaic modules. Here, we characterize the fracture mechanics properties of an epoxy based ECA, for both critical and subcritical loading conditions. Emphasis is put on the influence of different environmental conditions such as temperature and humidity. We found that high levels of humidity not only weaken the adhesive joint but also promote subcritical debonding at significantly lower driving forces than in dry environments.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72889439","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 : 2020-06-14DOI: 10.1109/PVSC45281.2020.9300914
J. Buencuerpo, J. Geisz, M. Young, Talysa R Klein, W. McMahon, E. Warren, A. Tamboli
Tandem devices are well known to surpass single junctions. However, the limitations of current-matching is a concern for changing spectra in terrestrial applications. Three terminal tandem (3T) devices can be more robust to these variations resulting in higher energy yield than single junction devices and two terminal series-connected tandems. We fabricate one-sun 3T tandem devices made of inverted grown III-V tandem (GaInP/GaAs) as a prototype of 3T tandems for stringing and measurement demonstrations. We demonstrate 3T tandem measurements that can be used to understand the use of 3T tandems in various constrained configurations.
{"title":"Stringing monolithic three terminal III-V tandems","authors":"J. Buencuerpo, J. Geisz, M. Young, Talysa R Klein, W. McMahon, E. Warren, A. Tamboli","doi":"10.1109/PVSC45281.2020.9300914","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300914","url":null,"abstract":"Tandem devices are well known to surpass single junctions. However, the limitations of current-matching is a concern for changing spectra in terrestrial applications. Three terminal tandem (3T) devices can be more robust to these variations resulting in higher energy yield than single junction devices and two terminal series-connected tandems. We fabricate one-sun 3T tandem devices made of inverted grown III-V tandem (GaInP/GaAs) as a prototype of 3T tandems for stringing and measurement demonstrations. We demonstrate 3T tandem measurements that can be used to understand the use of 3T tandems in various constrained configurations.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80421228","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 : 2020-06-14DOI: 10.1109/PVSC45281.2020.9300783
Dhruba B. Khadka, Yashihiro Shirai, M. Yanagida, K. Miyano
A number of non- toxic candidates such as Sn, Ge, Bi, and Sb based halide perovskites, etc. have been explored as Pb free HaPSCs Among these alternatives, Sn-based halide perovskites (Sn-HaP) are promising alternatives. The oxidative instability of tin-based halide perovskite (Sn-HaP) deteriorates the device performance. In this report, we have explored the role of Rb insertion in FASnI3lattice for device performance. The Rb incorporation in crystal lattice facilitates uniform morphology with better crystal quality and suppression of oxidation of Sn2+. The device analysis showed higher diffusion potential and mitigation of defect activities with RbCl additive in Sn-HaPSCs. This leads to the improvement in device performance and stability with the power conversion efficiency of ~3 % for pure FASnI3to 6 % for Rb incorporated FASnI3.
{"title":"Passivation of the Recombination Activities with Rubidium incorporation for Efficient and Stable Sn- HaP Solar Cells","authors":"Dhruba B. Khadka, Yashihiro Shirai, M. Yanagida, K. Miyano","doi":"10.1109/PVSC45281.2020.9300783","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300783","url":null,"abstract":"A number of non- toxic candidates such as Sn, Ge, Bi, and Sb based halide perovskites, etc. have been explored as Pb free HaPSCs Among these alternatives, Sn-based halide perovskites (Sn-HaP) are promising alternatives. The oxidative instability of tin-based halide perovskite (Sn-HaP) deteriorates the device performance. In this report, we have explored the role of Rb insertion in FASnI3lattice for device performance. The Rb incorporation in crystal lattice facilitates uniform morphology with better crystal quality and suppression of oxidation of Sn2+. The device analysis showed higher diffusion potential and mitigation of defect activities with RbCl additive in Sn-HaPSCs. This leads to the improvement in device performance and stability with the power conversion efficiency of ~3 % for pure FASnI3to 6 % for Rb incorporated FASnI3.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77196037","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 : 2020-06-14DOI: 10.1109/PVSC45281.2020.9300543
Meriç Fırat, H. S. Radhakrishnan, M. R. Payo, F. Duerinckx, Rajiv Sharma, J. Poortmans
The potential of in situ phosphorus (P)-doped polycrystalline silicon (poly-Si) films by low pressure chemical vapor deposition (LPCVD) was studied for the realization of poly-Si/SiOx passivating contacts. In situ doping of poly-Si, as an alternative to ex situ methods, could enable simpler fabrication of industrial solar cells featuring these passivating contacts. With this approach, recombination current densities down to 1.7 fA/cm2 and 3.5 fA/cm2 were achieved on saw-damage removed and textured Cz-Si surfaces, respectively. It was found that the use of thermal SiOx, high active doping in the poly-Si, and hydrogenation improve the passivation quality. In addition, while post-LPCVD annealing was also beneficial, dopant loss from poly-Si at high annealing thermal budgets was observed to be detrimental to the specific contact resistivity and passivation quality, thus making it crucial to mitigate such dopant losses.
{"title":"In Situ Phosphorus-Doped Poly-Si by Low Pressure Chemical Vapor Deposition for Passivating Contacts","authors":"Meriç Fırat, H. S. Radhakrishnan, M. R. Payo, F. Duerinckx, Rajiv Sharma, J. Poortmans","doi":"10.1109/PVSC45281.2020.9300543","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300543","url":null,"abstract":"The potential of in situ phosphorus (P)-doped polycrystalline silicon (poly-Si) films by low pressure chemical vapor deposition (LPCVD) was studied for the realization of poly-Si/SiOx passivating contacts. In situ doping of poly-Si, as an alternative to ex situ methods, could enable simpler fabrication of industrial solar cells featuring these passivating contacts. With this approach, recombination current densities down to 1.7 fA/cm2 and 3.5 fA/cm2 were achieved on saw-damage removed and textured Cz-Si surfaces, respectively. It was found that the use of thermal SiOx, high active doping in the poly-Si, and hydrogenation improve the passivation quality. In addition, while post-LPCVD annealing was also beneficial, dopant loss from poly-Si at high annealing thermal budgets was observed to be detrimental to the specific contact resistivity and passivation quality, thus making it crucial to mitigate such dopant losses.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81650954","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 : 2020-06-14DOI: 10.1109/PVSC45281.2020.9300472
P. Hsieh, Ming-Hsien Li, Wei-Chiao Hung, C. Yang, Peter Chen, I. Chen
In this article, we demonstrate mechanically stacked four-terminal perovskite-silicon tandem solar cells. N-type C-Si solar cell with PERT structure were used as the bottom cell and the perovskite solar cell on FTO glass substrate was used for top cell under 1.02 cm2 active area. In order to increase the FF for PSC, we introduce a metal mesh design for connecting TCO layers. With the metal mesh inside, the best power conversion efficiency (PCE) of 20.46% with 1.02cm2 was performed.
{"title":"Large Area (>1cm2) Efficient Perovskite/N type C-Si Tandem Solar Cell","authors":"P. Hsieh, Ming-Hsien Li, Wei-Chiao Hung, C. Yang, Peter Chen, I. Chen","doi":"10.1109/PVSC45281.2020.9300472","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300472","url":null,"abstract":"In this article, we demonstrate mechanically stacked four-terminal perovskite-silicon tandem solar cells. N-type C-Si solar cell with PERT structure were used as the bottom cell and the perovskite solar cell on FTO glass substrate was used for top cell under 1.02 cm2 active area. In order to increase the FF for PSC, we introduce a metal mesh design for connecting TCO layers. With the metal mesh inside, the best power conversion efficiency (PCE) of 20.46% with 1.02cm2 was performed.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81863286","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 : 2020-06-14DOI: 10.1109/PVSC45281.2020.9300415
C. Camus, C. Kaspari, J. Rappich, V. Blank, N. Nickel
In this paper a novel method for in-situ monitoring of a complete perovskite fabrication process by means of highspeed spectral reflectance measurements is introduced. Firstly, the spin-coating deposition and secondly, the annealing process is monitored. The results clearly show that this method is capable to fully characterize the perovskite growth kinetics and the phase transitions during thin film annealing. Thereby in-situ reflectance constitutes an ideal method for monitoring perovskite formation, which as of today often suffers from poor reproducibility. This paper focuses on the experimental implementation of the in-situ- reflectance measurements during spin-coating.
{"title":"Going beyond Alchemy: In-situ Analysis of Perovskite Growth by Optical Reflectance","authors":"C. Camus, C. Kaspari, J. Rappich, V. Blank, N. Nickel","doi":"10.1109/PVSC45281.2020.9300415","DOIUrl":"https://doi.org/10.1109/PVSC45281.2020.9300415","url":null,"abstract":"In this paper a novel method for in-situ monitoring of a complete perovskite fabrication process by means of highspeed spectral reflectance measurements is introduced. Firstly, the spin-coating deposition and secondly, the annealing process is monitored. The results clearly show that this method is capable to fully characterize the perovskite growth kinetics and the phase transitions during thin film annealing. Thereby in-situ reflectance constitutes an ideal method for monitoring perovskite formation, which as of today often suffers from poor reproducibility. This paper focuses on the experimental implementation of the in-situ- reflectance measurements during spin-coating.","PeriodicalId":6773,"journal":{"name":"2020 47th IEEE Photovoltaic Specialists Conference (PVSC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82057068","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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