Pub Date : 1996-05-13DOI: 10.1109/PVSC.1996.564407
W. Knaupp
Photovoltaic energy in the building environment is a very interesting application. On existing building roofs, the installation of photovoltaic generators is a common mounting configuration. It is important to assess and predict the operational behaviour regarding energy output, power rating and critical operation limits of such modules. This contribution summarizes some detailed experimental and theoretical examinations regarding the operational behaviour of roof-installed PV power system modules. Reverse ventilation was analyzed on the basis of buoyancy forces and pressure loss mechanisms. The correlations were transferred to a computer program PVROOF and verified in the ZSW test site, Germany. Experimental and simulation results regarding the influence of roof cover and the distance between the roof and the PV module are shown. With such results, roof-mounted PV power system installations can be optimized with respect to electrical and thermal energy output.
{"title":"Operation behaviour of roof installed photovoltaic modules","authors":"W. Knaupp","doi":"10.1109/PVSC.1996.564407","DOIUrl":"https://doi.org/10.1109/PVSC.1996.564407","url":null,"abstract":"Photovoltaic energy in the building environment is a very interesting application. On existing building roofs, the installation of photovoltaic generators is a common mounting configuration. It is important to assess and predict the operational behaviour regarding energy output, power rating and critical operation limits of such modules. This contribution summarizes some detailed experimental and theoretical examinations regarding the operational behaviour of roof-installed PV power system modules. Reverse ventilation was analyzed on the basis of buoyancy forces and pressure loss mechanisms. The correlations were transferred to a computer program PVROOF and verified in the ZSW test site, Germany. Experimental and simulation results regarding the influence of roof cover and the distance between the roof and the PV module are shown. With such results, roof-mounted PV power system installations can be optimized with respect to electrical and thermal energy output.","PeriodicalId":410394,"journal":{"name":"Conference Record of the Twenty Fifth IEEE Photovoltaic Specialists Conference - 1996","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126592356","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 : 1996-05-13DOI: 10.1109/PVSC.1996.564424
C. Jennings, B. Farmer, T. Townsend, P. Hutchinson, T. Reyes, C. Whitaker, J. Gough, D. Shipman, W. Stolte, H. Wenger, T. Hoff
Photovoltaics for Utility Scale Applications (PVUSA) is a national cooperative research and development project with a mission to acquire information through field installation and testing of grid-connected photovoltaic (PV) technologies and to provide the information to utilities and other participants. This paper updates the project's progress and summarizes performance, cost, and value results obtained in the 10 years since project inception.
{"title":"PVUSA-the first decade of experience","authors":"C. Jennings, B. Farmer, T. Townsend, P. Hutchinson, T. Reyes, C. Whitaker, J. Gough, D. Shipman, W. Stolte, H. Wenger, T. Hoff","doi":"10.1109/PVSC.1996.564424","DOIUrl":"https://doi.org/10.1109/PVSC.1996.564424","url":null,"abstract":"Photovoltaics for Utility Scale Applications (PVUSA) is a national cooperative research and development project with a mission to acquire information through field installation and testing of grid-connected photovoltaic (PV) technologies and to provide the information to utilities and other participants. This paper updates the project's progress and summarizes performance, cost, and value results obtained in the 10 years since project inception.","PeriodicalId":410394,"journal":{"name":"Conference Record of the Twenty Fifth IEEE Photovoltaic Specialists Conference - 1996","volume":"183 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126779566","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 : 1996-05-13DOI: 10.1109/PVSC.1996.564276
M. Schmitt, U. Rau, J. Parisi, W. Riedl, J. Rimmasch, F. Karg
Within a systematic study, the authors investigate the frequency, temperature and bias voltage dependence of the complex admittance of Cu(In,Ga)Se/sub 2/ solar cells prepared by rapid thermal processing. Measured admittance spectra performed in a frequency range between 100 Hz and 13 MHz and a temperature range from 5 K to 300 K uncover distinct loss peaks related to a series of impurity states in the cell material. The temperature dependence of the peak frequency shows thermal activation. Four different activation energies could be identified with values of about 260 meV, 195 meV, 44 meV, and 22 meV corresponding to the energetic position of four distinct trap levels within the Cu(In,Ga)Se/sub 2/ material. From the dependence of the admittance on the voltage bias, it is possible to distinguish between majority carrier and minority carrier traps. The authors also demonstrate that the defect structure of the Cu(In,Ga)Se/sub 2/ cells displays metastable behavior.
{"title":"Dielectric spectroscopy of relaxation processes in Cu(In,Ga)Se/sub 2/ solar cells","authors":"M. Schmitt, U. Rau, J. Parisi, W. Riedl, J. Rimmasch, F. Karg","doi":"10.1109/PVSC.1996.564276","DOIUrl":"https://doi.org/10.1109/PVSC.1996.564276","url":null,"abstract":"Within a systematic study, the authors investigate the frequency, temperature and bias voltage dependence of the complex admittance of Cu(In,Ga)Se/sub 2/ solar cells prepared by rapid thermal processing. Measured admittance spectra performed in a frequency range between 100 Hz and 13 MHz and a temperature range from 5 K to 300 K uncover distinct loss peaks related to a series of impurity states in the cell material. The temperature dependence of the peak frequency shows thermal activation. Four different activation energies could be identified with values of about 260 meV, 195 meV, 44 meV, and 22 meV corresponding to the energetic position of four distinct trap levels within the Cu(In,Ga)Se/sub 2/ material. From the dependence of the admittance on the voltage bias, it is possible to distinguish between majority carrier and minority carrier traps. The authors also demonstrate that the defect structure of the Cu(In,Ga)Se/sub 2/ cells displays metastable behavior.","PeriodicalId":410394,"journal":{"name":"Conference Record of the Twenty Fifth IEEE Photovoltaic Specialists Conference - 1996","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126807358","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 : 1996-05-13DOI: 10.1109/PVSC.1996.564013
R. Dally, J.R. Kululka, J. Schwartz
Bypass diodes are integrated onto GaAs/Ge solar cells by selectively thinning a pocket into the backside of the solar cell's germanium substrate, electrically connecting the two devices via insulated metal foil tabs (Ag, Ag/Kovar or Ag/Mo) attached by thermal compression bonding (welding) and/or soldering and bonding the 3 mm thick silicon diode chip into the germanium pocket with a standard space qualified adhesive. This efficient and synergistic method of integration maintains the modularity of the solar cell unit, minimizes active area obscuration, heat sinks the diode and eliminates the need for discrete bypass diode wiring at the solar panel level. The approach is also applicable to future high efficiency, multijunction solar cells. Qualification status, performance results and manufacturing capabilities are discussed.
{"title":"The design, qualification and use of bypass diode integration onto GaAs/Ge solar cells","authors":"R. Dally, J.R. Kululka, J. Schwartz","doi":"10.1109/PVSC.1996.564013","DOIUrl":"https://doi.org/10.1109/PVSC.1996.564013","url":null,"abstract":"Bypass diodes are integrated onto GaAs/Ge solar cells by selectively thinning a pocket into the backside of the solar cell's germanium substrate, electrically connecting the two devices via insulated metal foil tabs (Ag, Ag/Kovar or Ag/Mo) attached by thermal compression bonding (welding) and/or soldering and bonding the 3 mm thick silicon diode chip into the germanium pocket with a standard space qualified adhesive. This efficient and synergistic method of integration maintains the modularity of the solar cell unit, minimizes active area obscuration, heat sinks the diode and eliminates the need for discrete bypass diode wiring at the solar panel level. The approach is also applicable to future high efficiency, multijunction solar cells. Qualification status, performance results and manufacturing capabilities are discussed.","PeriodicalId":410394,"journal":{"name":"Conference Record of the Twenty Fifth IEEE Photovoltaic Specialists Conference - 1996","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128783391","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 : 1996-05-13DOI: 10.1109/PVSC.1996.564045
U. Rau, T. Meyer, A. Goldbach, R. Brendel, J. H. Werner
We investigate the optical and electronic properties of thin-film silicon solar cells by means of numerical simulations. The optical design under investigation is the encapsulated-V texture which is capable of absorbing sunlight corresponding to a maximum short circuit current density of 35 mA/cm/sup 2/. Since the layer thickness can be restricted to only 4 /spl mu/m, the encapsulated-V structure provides also a good collection efficiency for photogenerated charge carriers. Practical efficiencies around 12% can be expected for Si material with a minority carrier lifetime as low as 10 ns. Increased lifetimes of 100 ns allow for about 14% efficiency. The benefit of multiple junctions strongly depends on surface recombination. The efficiency of a single junction cell can be improved from 10% to 13% by a three junction device if the surface recombination velocity is as high as 10/sup 5/ cm/s. For moderate surface recombination the gain is only 1%.
{"title":"Numerical simulation of innovative device structures for silicon thin-film solar cells","authors":"U. Rau, T. Meyer, A. Goldbach, R. Brendel, J. H. Werner","doi":"10.1109/PVSC.1996.564045","DOIUrl":"https://doi.org/10.1109/PVSC.1996.564045","url":null,"abstract":"We investigate the optical and electronic properties of thin-film silicon solar cells by means of numerical simulations. The optical design under investigation is the encapsulated-V texture which is capable of absorbing sunlight corresponding to a maximum short circuit current density of 35 mA/cm/sup 2/. Since the layer thickness can be restricted to only 4 /spl mu/m, the encapsulated-V structure provides also a good collection efficiency for photogenerated charge carriers. Practical efficiencies around 12% can be expected for Si material with a minority carrier lifetime as low as 10 ns. Increased lifetimes of 100 ns allow for about 14% efficiency. The benefit of multiple junctions strongly depends on surface recombination. The efficiency of a single junction cell can be improved from 10% to 13% by a three junction device if the surface recombination velocity is as high as 10/sup 5/ cm/s. For moderate surface recombination the gain is only 1%.","PeriodicalId":410394,"journal":{"name":"Conference Record of the Twenty Fifth IEEE Photovoltaic Specialists Conference - 1996","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129138944","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 : 1996-05-13DOI: 10.1109/PVSC.1996.564041
O. Breitenstein, K. Iwig, I. Konovalov
Dynamical Precision Contact Thermography has been used to map the forward current in the dark of 10/spl times/10 cm/sup 2/ sized multicrystalline solar cells made of block-cast silicon material. Moreover, local I-V-characteristics have been measured thermally. Extended regions of increased current density as well as local shunts at the edges, under, and between grid lines have been observed. In shunt positions the cells have been investigated in detail using scanning electron microscope techniques. Only some of the local shunts are related to accumulations of grain boundaries, others are pn-junction defects. The dominant shunts often have been found at the edges of the cells. The dependence of the shunt strength on elastic deformation of the cells, which is sometimes observed, indicates that mechanical stress may influence certain shunts. The quantitative influence of shunts on the efficiency is shown to increase to above 30% for illuminations below 0.2 suns.
{"title":"Identification of factors reducing Voc in MC silicon solar cells","authors":"O. Breitenstein, K. Iwig, I. Konovalov","doi":"10.1109/PVSC.1996.564041","DOIUrl":"https://doi.org/10.1109/PVSC.1996.564041","url":null,"abstract":"Dynamical Precision Contact Thermography has been used to map the forward current in the dark of 10/spl times/10 cm/sup 2/ sized multicrystalline solar cells made of block-cast silicon material. Moreover, local I-V-characteristics have been measured thermally. Extended regions of increased current density as well as local shunts at the edges, under, and between grid lines have been observed. In shunt positions the cells have been investigated in detail using scanning electron microscope techniques. Only some of the local shunts are related to accumulations of grain boundaries, others are pn-junction defects. The dominant shunts often have been found at the edges of the cells. The dependence of the shunt strength on elastic deformation of the cells, which is sometimes observed, indicates that mechanical stress may influence certain shunts. The quantitative influence of shunts on the efficiency is shown to increase to above 30% for illuminations below 0.2 suns.","PeriodicalId":410394,"journal":{"name":"Conference Record of the Twenty Fifth IEEE Photovoltaic Specialists Conference - 1996","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127344500","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 : 1996-05-13DOI: 10.1109/PVSC.1996.564001
P. Stella, R. Ross, B.S. Smith, G. Glenn, K.S. Sharmit
The MGS mission is one of the first major planetary missions conducted under the new NASA Faster, Better, Cheaper guidelines. Ironically, mission requirements make the MGS solar array one of the most challenging designs built for NASA. Not only will the array include silicon and GaAs/Ge panels, but the solar array will be used to aerobrake the spacecraft in the upper regions of the Martian atmosphere. Consequently, even though a mission to Mars is normally typified by cold temperatures, aerobraking imposes a high temperature requirement of nearly 180/spl deg/C, higher than that experienced by any previous array. The array size is tightly constrained by mass and area. Since the aerobraking occurs early in the mission, it is necessary to subsequently survive up to 20000 lower temperature thermal cycles. Furthermore, the location of a magnetometer directly on the array structure requires the minimization of circuit induced magnetic moments. This paper provides an overview of the array design and performance. In addition, the high temperature capable design and development are discussed in detail.
{"title":"Mars Global Surveyor (MGS) high temperature survival solar array","authors":"P. Stella, R. Ross, B.S. Smith, G. Glenn, K.S. Sharmit","doi":"10.1109/PVSC.1996.564001","DOIUrl":"https://doi.org/10.1109/PVSC.1996.564001","url":null,"abstract":"The MGS mission is one of the first major planetary missions conducted under the new NASA Faster, Better, Cheaper guidelines. Ironically, mission requirements make the MGS solar array one of the most challenging designs built for NASA. Not only will the array include silicon and GaAs/Ge panels, but the solar array will be used to aerobrake the spacecraft in the upper regions of the Martian atmosphere. Consequently, even though a mission to Mars is normally typified by cold temperatures, aerobraking imposes a high temperature requirement of nearly 180/spl deg/C, higher than that experienced by any previous array. The array size is tightly constrained by mass and area. Since the aerobraking occurs early in the mission, it is necessary to subsequently survive up to 20000 lower temperature thermal cycles. Furthermore, the location of a magnetometer directly on the array structure requires the minimization of circuit induced magnetic moments. This paper provides an overview of the array design and performance. In addition, the high temperature capable design and development are discussed in detail.","PeriodicalId":410394,"journal":{"name":"Conference Record of the Twenty Fifth IEEE Photovoltaic Specialists Conference - 1996","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133549630","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 : 1996-05-13DOI: 10.1109/PVSC.1996.564347
J.-H. Zhao, A. Wang, E. Abbaspour-Sani, F. Yun, M. Green, D. King
This paper reports a recent result of 22.3% solar cell module efficiency independently confirmed at Sandia National Laboratories. This is the highest confirmed module efficiency for a module of this size achieved by solar cells made on any material. Modified double layer antireflection coated PERL (passivated emitter, rear locally-diffused) solar cells of 23% efficiency are used in this module. This double layer coating, together with the redesigned solar cell structure and a shingled encapsulation technique, considerably contributed to this efficiency improvement.
{"title":"22.3% efficient silicon solar cell module","authors":"J.-H. Zhao, A. Wang, E. Abbaspour-Sani, F. Yun, M. Green, D. King","doi":"10.1109/PVSC.1996.564347","DOIUrl":"https://doi.org/10.1109/PVSC.1996.564347","url":null,"abstract":"This paper reports a recent result of 22.3% solar cell module efficiency independently confirmed at Sandia National Laboratories. This is the highest confirmed module efficiency for a module of this size achieved by solar cells made on any material. Modified double layer antireflection coated PERL (passivated emitter, rear locally-diffused) solar cells of 23% efficiency are used in this module. This double layer coating, together with the redesigned solar cell structure and a shingled encapsulation technique, considerably contributed to this efficiency improvement.","PeriodicalId":410394,"journal":{"name":"Conference Record of the Twenty Fifth IEEE Photovoltaic Specialists Conference - 1996","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130466685","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 : 1996-05-13DOI: 10.1109/PVSC.1996.564016
V. Grilikhes, V. Rumyantsev, M. Shvarts
The use of a high-efficiency space concentrator photovoltaic (PV) modules requires a development of the testing methods and a measuring equipment for their laboratory inspection. In this case it is necessary to take into account the specific behaviour of module elements under operating conditions as well as interaction between optical and electrogenerating parts. The aim of this work is to develop the laboratory (indoor) testing procedure for concentrator PV modules, to predict their characteristics during the space flight experiment, to apply the developed methods to the lens concentrator PV modules and to check indoor results in preliminary terrestrial (outdoor) experiment.
{"title":"Indoor and outdoor testing of space concentrator AlGaAs/GaAs photovoltaic modules with Fresnel lenses","authors":"V. Grilikhes, V. Rumyantsev, M. Shvarts","doi":"10.1109/PVSC.1996.564016","DOIUrl":"https://doi.org/10.1109/PVSC.1996.564016","url":null,"abstract":"The use of a high-efficiency space concentrator photovoltaic (PV) modules requires a development of the testing methods and a measuring equipment for their laboratory inspection. In this case it is necessary to take into account the specific behaviour of module elements under operating conditions as well as interaction between optical and electrogenerating parts. The aim of this work is to develop the laboratory (indoor) testing procedure for concentrator PV modules, to predict their characteristics during the space flight experiment, to apply the developed methods to the lens concentrator PV modules and to check indoor results in preliminary terrestrial (outdoor) experiment.","PeriodicalId":410394,"journal":{"name":"Conference Record of the Twenty Fifth IEEE Photovoltaic Specialists Conference - 1996","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116554665","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 : 1996-05-13DOI: 10.1109/PVSC.1996.563981
D. Marvin, M. Gates
Gallium arsenide on germanium (GaAs/Ge) solar cells are being used on an increasing fraction of space missions because of their increased efficiency over silicon solar cells. Three recent flight experiments in orbits that rapidly accumulate radiation exposure have included GaAs-containing cells of various designs. The data from these experiments presented in this paper verify the radiation degradation models for these solar cells and give confidence in their projected performance in proton-dominated orbits.
{"title":"Results of three recent GaAs flight experiments: Ascot, PASP-Plus, and STRV-1b","authors":"D. Marvin, M. Gates","doi":"10.1109/PVSC.1996.563981","DOIUrl":"https://doi.org/10.1109/PVSC.1996.563981","url":null,"abstract":"Gallium arsenide on germanium (GaAs/Ge) solar cells are being used on an increasing fraction of space missions because of their increased efficiency over silicon solar cells. Three recent flight experiments in orbits that rapidly accumulate radiation exposure have included GaAs-containing cells of various designs. The data from these experiments presented in this paper verify the radiation degradation models for these solar cells and give confidence in their projected performance in proton-dominated orbits.","PeriodicalId":410394,"journal":{"name":"Conference Record of the Twenty Fifth IEEE Photovoltaic Specialists Conference - 1996","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130968585","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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