Georgios Charalampopoulos, Ilias Maniatis, Maria Daletou
The replacement of unsustainable noble-metal catalysts with platinum group metal (PGM)-free catalysts for oxygen reduction reaction (ORR) is essential for material wise and market value viable PEMFCs. Despite the tremendous efforts involved in their development, many drawbacks persist that include poor design of the architecture and chemical composition, control over the synthesis and poor stability, which seriously degrades their performance. These challenges are universally recognized and lead to a strong focus on designing alternative catalysts. Among the investigated candidates, Me–N-C catalysts are the most promising. In this work, the synthesis, characterization and evaluation of several Fe–N–C materials are presented. The synthetic approach involves templating using silicon-based materials. Structural, physicochemical, and electrochemical characterization in terms of ORR activity is also performed.
{"title":"Non-PGM Cathode Electrocatalysts for PEM Fuel Cells","authors":"Georgios Charalampopoulos, Ilias Maniatis, Maria Daletou","doi":"10.1149/11204.0335ecst","DOIUrl":"https://doi.org/10.1149/11204.0335ecst","url":null,"abstract":"The replacement of unsustainable noble-metal catalysts with platinum group metal (PGM)-free catalysts for oxygen reduction reaction (ORR) is essential for material wise and market value viable PEMFCs. Despite the tremendous efforts involved in their development, many drawbacks persist that include poor design of the architecture and chemical composition, control over the synthesis and poor stability, which seriously degrades their performance. These challenges are universally recognized and lead to a strong focus on designing alternative catalysts. Among the investigated candidates, Me–N-C catalysts are the most promising. In this work, the synthesis, characterization and evaluation of several Fe–N–C materials are presented. The synthetic approach involves templating using silicon-based materials. Structural, physicochemical, and electrochemical characterization in terms of ORR activity is also performed.","PeriodicalId":11473,"journal":{"name":"ECS Transactions","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135243238","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}
To achieve high power density operation of polymer electrolyte fuel cells (PEFCs), it is required to realize higher performance catalyst layer. Because dispersion structure of catalyst ink strongly affects the catalyst layer structure, it is crucial to understand the dispersion mechanism of PEFC catalyst ink. Though water/ethanol solution is used as solvent of the catalyst ink, decomposition of ethanol by Platinum catalyst strongly affect dispersion of the catalyst ink. In this study, influence of ethanol decomposition on dispersion of catalyst inks were investigated. Among the decomposition byproducts of ethanol, results of rheology characteristics and direct observation by scanning electron assisted dielectric microscopy clearly showed that acetaldehyde has a significant impact on aggregation of catalyst ink. To reveal the mechanism of aggregation, particle size measurement and ionomer adsorption fraction measurement of the catalyst ink were carried out. The results suggested that the acetaldehyde impede adsorption of the ionomer on Platinum catalyst.
{"title":"Influence of Ethanol Decomposition on Dispersion of PEFC Catalyst Ink","authors":"Takashi Sasabe, Toshihiko Ogura, Koki Okada, Haruto Oka, Katsunori Sakai, Shuichiro Hirai","doi":"10.1149/11204.0093ecst","DOIUrl":"https://doi.org/10.1149/11204.0093ecst","url":null,"abstract":"To achieve high power density operation of polymer electrolyte fuel cells (PEFCs), it is required to realize higher performance catalyst layer. Because dispersion structure of catalyst ink strongly affects the catalyst layer structure, it is crucial to understand the dispersion mechanism of PEFC catalyst ink. Though water/ethanol solution is used as solvent of the catalyst ink, decomposition of ethanol by Platinum catalyst strongly affect dispersion of the catalyst ink. In this study, influence of ethanol decomposition on dispersion of catalyst inks were investigated. Among the decomposition byproducts of ethanol, results of rheology characteristics and direct observation by scanning electron assisted dielectric microscopy clearly showed that acetaldehyde has a significant impact on aggregation of catalyst ink. To reveal the mechanism of aggregation, particle size measurement and ionomer adsorption fraction measurement of the catalyst ink were carried out. The results suggested that the acetaldehyde impede adsorption of the ionomer on Platinum catalyst.","PeriodicalId":11473,"journal":{"name":"ECS Transactions","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135243868","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}
To keep the scaling progress going, we must go three dimensional (3D). This paper outlines some technology challenges and solutions to integrate Ge p-type MOSFETs sequentially on Si CMOS. Such a solution addresses the grand challenge to enable increased device density. However, the device itself does not have to scale but at the same time innovative solutions are suggested for low supply voltage operation enabling energy efficient integrated circuits (ICs) that will not be dominated by energy consumption in interconnects. By stacking the transistors on top of each other, and connecting them with inter-tier via, the density of transistors per unit area increases. This approach demands that transistors are fabricated at a lower temperature than today’s Si CMOS technology. Here, we have focused on Ge based transistors, which have an inherently lower process temperature compared to Si transistors. Several technological and design breakthroughs towards realizing Ge based sequential 3D circuits are discussed.
{"title":"(Invited) Sequential 3D Integration of Ge Transistors on Si CMOS","authors":"Mikael Ostling, Per-Erik Hellstrom","doi":"10.1149/11201.0013ecst","DOIUrl":"https://doi.org/10.1149/11201.0013ecst","url":null,"abstract":"To keep the scaling progress going, we must go three dimensional (3D). This paper outlines some technology challenges and solutions to integrate Ge p-type MOSFETs sequentially on Si CMOS. Such a solution addresses the grand challenge to enable increased device density. However, the device itself does not have to scale but at the same time innovative solutions are suggested for low supply voltage operation enabling energy efficient integrated circuits (ICs) that will not be dominated by energy consumption in interconnects. By stacking the transistors on top of each other, and connecting them with inter-tier via, the density of transistors per unit area increases. This approach demands that transistors are fabricated at a lower temperature than today’s Si CMOS technology. Here, we have focused on Ge based transistors, which have an inherently lower process temperature compared to Si transistors. Several technological and design breakthroughs towards realizing Ge based sequential 3D circuits are discussed.","PeriodicalId":11473,"journal":{"name":"ECS Transactions","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135243873","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}
Abhas Mehta, Hisashi Shichijo, Jungwoo Joh, Chang Suh, Moon Kim
This work describes the cause-effect-based degradation process of the p-GaN gate in Enhancement-mode (E-mode) GaN High Electron Mobility Transistors (HEMTs) using gate stressing and failure analysis (FA). We found no correlation between time-to-fail and initial gate current (I G0 ). Instead, a higher impact of temperature was found on the gate current of the device (I G ) and time-to-fail at 100 °C. Gate failure at constant voltage stress was a single-stage failure. Under constant current stress, the gate shows a multi-stage failure. The breakdown starts with increased gate current leading to Schottky barrier leakage and finally to catastrophic contact failure. The metal/p-GaN interface at the gate finger becomes the weakest part of the gate stack. Metal/p-GaN interface and surface defects develop as percolation paths acting as leakage sources, and nano-cracks have been observed in the gate cap. FA also shows physical degradation at the metal/p-GaN cap due to electrical stress.
{"title":"Degradation and Failure Mechanism of p-GaN Gate E-Mode GaN HEMTs","authors":"Abhas Mehta, Hisashi Shichijo, Jungwoo Joh, Chang Suh, Moon Kim","doi":"10.1149/11202.0009ecst","DOIUrl":"https://doi.org/10.1149/11202.0009ecst","url":null,"abstract":"This work describes the cause-effect-based degradation process of the p-GaN gate in Enhancement-mode (E-mode) GaN High Electron Mobility Transistors (HEMTs) using gate stressing and failure analysis (FA). We found no correlation between time-to-fail and initial gate current (I G0 ). Instead, a higher impact of temperature was found on the gate current of the device (I G ) and time-to-fail at 100 °C. Gate failure at constant voltage stress was a single-stage failure. Under constant current stress, the gate shows a multi-stage failure. The breakdown starts with increased gate current leading to Schottky barrier leakage and finally to catastrophic contact failure. The metal/p-GaN interface at the gate finger becomes the weakest part of the gate stack. Metal/p-GaN interface and surface defects develop as percolation paths acting as leakage sources, and nano-cracks have been observed in the gate cap. FA also shows physical degradation at the metal/p-GaN cap due to electrical stress.","PeriodicalId":11473,"journal":{"name":"ECS Transactions","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135244053","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}
Screen-printing is a cheap and easy thin film deposition technique utilized in energy devices fabrication, specifically, in solid oxide electrochemical cells (SOCs). In this study, LSM-YSZ, a promising component material for SOCs application was deposited on YSZ electrolyte via screen-printing. Specifically, the study aimed to investigate the effect of the solvent used in screen-printing and the effect of varying ink formulation on the quality of the deposited film. LSM-YSZ precursor powders synthesized via glycine-nitrate combustion process (GNP) were screen-printed on YSZ substrate using ethanol and alpha-terpineol solvents. The structure and morphology of LSM-YSZ thin films using two solvents were compared. Results showed that both solvents produced a rhombohedral LSM and cubic YSZ thin films and the use of a-terpineol solvent with higher solid content produced a desired uniform and porous morphology with homogenous pore distribution as revealed by XRD and SEM morphological results.
{"title":"(Digital Only Presentation) Effects of Ink Solvent on the Screen-Printing Fabrication and Morphology of LSM-YSZ Thin Films Deposited on YSZ Substrate for Solid Oxide Electrochemical Cells","authors":"Jessa Hablado, Rinlee Cervera","doi":"10.1149/11205.0169ecst","DOIUrl":"https://doi.org/10.1149/11205.0169ecst","url":null,"abstract":"Screen-printing is a cheap and easy thin film deposition technique utilized in energy devices fabrication, specifically, in solid oxide electrochemical cells (SOCs). In this study, LSM-YSZ, a promising component material for SOCs application was deposited on YSZ electrolyte via screen-printing. Specifically, the study aimed to investigate the effect of the solvent used in screen-printing and the effect of varying ink formulation on the quality of the deposited film. LSM-YSZ precursor powders synthesized via glycine-nitrate combustion process (GNP) were screen-printed on YSZ substrate using ethanol and alpha-terpineol solvents. The structure and morphology of LSM-YSZ thin films using two solvents were compared. Results showed that both solvents produced a rhombohedral LSM and cubic YSZ thin films and the use of a-terpineol solvent with higher solid content produced a desired uniform and porous morphology with homogenous pore distribution as revealed by XRD and SEM morphological results.","PeriodicalId":11473,"journal":{"name":"ECS Transactions","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135244640","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}
Yohei Nagatomo, Yuya Tachikawa, Stephen Matthew Lyth, Junko Matsuda, Kazunari Sasaki
Reversible solid oxide cells (r-SOCs) are electrochemical energy devices that can reversibly switch between power generation by solid oxide fuel cells (SOFCs), and hydrogen production by solid oxide electrolysis cells (SOECs) the reverse operation of SOFCs. For the development of high-performance and durable r-SOCs, it is essential to understand not only the I-V characteristics but also the electrode reaction processes systematically. Here in this study, Ni-GDC cermet fuel electrodes, a composite of Ni and mixed-conducting Gd-doped ceria (GDC), were prepared at different sintering temperatures and electrode thicknesses. Electrochemical impedance measurements and distribution of relaxation times (DRT) analysis were performed in both SOFC and SOEC modes to investigate the influence of fabrication conditions on the fuel electrode reaction processes.
{"title":"Distribution of Relaxation Times of Fuel Electrodes for Reversible Solid Oxide Cells Fabricated Under Various Conditions","authors":"Yohei Nagatomo, Yuya Tachikawa, Stephen Matthew Lyth, Junko Matsuda, Kazunari Sasaki","doi":"10.1149/11205.0121ecst","DOIUrl":"https://doi.org/10.1149/11205.0121ecst","url":null,"abstract":"Reversible solid oxide cells (r-SOCs) are electrochemical energy devices that can reversibly switch between power generation by solid oxide fuel cells (SOFCs), and hydrogen production by solid oxide electrolysis cells (SOECs) the reverse operation of SOFCs. For the development of high-performance and durable r-SOCs, it is essential to understand not only the I-V characteristics but also the electrode reaction processes systematically. Here in this study, Ni-GDC cermet fuel electrodes, a composite of Ni and mixed-conducting Gd-doped ceria (GDC), were prepared at different sintering temperatures and electrode thicknesses. Electrochemical impedance measurements and distribution of relaxation times (DRT) analysis were performed in both SOFC and SOEC modes to investigate the influence of fabrication conditions on the fuel electrode reaction processes.","PeriodicalId":11473,"journal":{"name":"ECS Transactions","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135245713","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}
In this study, an unsteady numerical simulation of PEFCs using the VOF method was performed to investigate the relationship between wettability of gas diffusion layer (GDL) substrates and liquid water drainage. The simulations were conducted with contact angle of 60°, 90°, 110°, 150°. The simulation results showed that the more hydrophobic is, the more liquid water movement was facilitated. Also, in the case of higher contact angles, the contact area between liquid water and substrates was decreased, and the area of gas-liquid interface was increased, and it was observed that the curvature of gas-liquid interface increased.
{"title":"Numerical Simulation of Liquid Water Behavior in PEFCs with Different GDL Wettability","authors":"Hiroshi Naito, Shuichiro Hirai","doi":"10.1149/11204.0037ecst","DOIUrl":"https://doi.org/10.1149/11204.0037ecst","url":null,"abstract":"In this study, an unsteady numerical simulation of PEFCs using the VOF method was performed to investigate the relationship between wettability of gas diffusion layer (GDL) substrates and liquid water drainage. The simulations were conducted with contact angle of 60°, 90°, 110°, 150°. The simulation results showed that the more hydrophobic is, the more liquid water movement was facilitated. Also, in the case of higher contact angles, the contact area between liquid water and substrates was decreased, and the area of gas-liquid interface was increased, and it was observed that the curvature of gas-liquid interface increased.","PeriodicalId":11473,"journal":{"name":"ECS Transactions","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135199837","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}
A shorter switching time and smaller conduction and switching losses are the key advantages of GaN power devices over Si technology. Further improvements of GaN HEMT technology will require new design approaches including SiC and even, possibly, diamond substrates, gate and drain edge engineering (beyond just using field plates) for optimizing the voltage distribution in the drain-to-gate spacing to using perforated channel design and a low conducting passivation for smoothing or even eliminating the sharp maximum of the electric field in the vicinity of the gate and field plate edges on switching time.
{"title":"(Invited) Switching Characteristics of GaN Power Transistors","authors":"Michael Shur, Xueqing Liu, Trond Ytterdal","doi":"10.1149/11202.0045ecst","DOIUrl":"https://doi.org/10.1149/11202.0045ecst","url":null,"abstract":"A shorter switching time and smaller conduction and switching losses are the key advantages of GaN power devices over Si technology. Further improvements of GaN HEMT technology will require new design approaches including SiC and even, possibly, diamond substrates, gate and drain edge engineering (beyond just using field plates) for optimizing the voltage distribution in the drain-to-gate spacing to using perforated channel design and a low conducting passivation for smoothing or even eliminating the sharp maximum of the electric field in the vicinity of the gate and field plate edges on switching time.","PeriodicalId":11473,"journal":{"name":"ECS Transactions","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135199846","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}
Two Surface Activated Bonding (SAB) methods will be proposed to enable low-temperature hybrid bonding for 3D integration. A modified one involves surface activation processes using Ar fast-atom-beam bombardment with simultaneous co-sputtering of Si nano-adhesion layer, followed by sequential plasma irradiation with N2 radicals. In the other one, we will connect two device wafers not in a hybrid but all-Cu bonding. A small insulation area surrounds the Cu pads on the wafer, while the rest is covered with Cu solid layers. These solid layers constitute the ground plane, power plane, or their paired layers and may contribute to heat dissipation when connected to thermal vias. The two wafers are connected only by bonding on the Cu electrodes and solid layers. Cu-Cu direct bonding is possible at room temperature by applying the standard SAB directly. Room-temperature bonding is overwhelmingly advantageous for bonding heterogeneous devices and wafers.
{"title":"(Invited) Modified SAB Methods for Hybrid and All-Cu Bonding for 3D Integration below 200ºC","authors":"Tadatomo Suga, Kanji Otsuka","doi":"10.1149/11203.0103ecst","DOIUrl":"https://doi.org/10.1149/11203.0103ecst","url":null,"abstract":"Two Surface Activated Bonding (SAB) methods will be proposed to enable low-temperature hybrid bonding for 3D integration. A modified one involves surface activation processes using Ar fast-atom-beam bombardment with simultaneous co-sputtering of Si nano-adhesion layer, followed by sequential plasma irradiation with N2 radicals. In the other one, we will connect two device wafers not in a hybrid but all-Cu bonding. A small insulation area surrounds the Cu pads on the wafer, while the rest is covered with Cu solid layers. These solid layers constitute the ground plane, power plane, or their paired layers and may contribute to heat dissipation when connected to thermal vias. The two wafers are connected only by bonding on the Cu electrodes and solid layers. Cu-Cu direct bonding is possible at room temperature by applying the standard SAB directly. Room-temperature bonding is overwhelmingly advantageous for bonding heterogeneous devices and wafers.","PeriodicalId":11473,"journal":{"name":"ECS Transactions","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135243253","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 gas diffusion layer (GDL) enables and influences the internal transport of fuel, oxygen, electricity, heat and water. The GDL is made up of the macroporous substrate and the microporous layer. To achieve the hydrophobicity required for water management, the two layers are typically treated with polytetrafluoroethylene (PTFE). Degradation of GDL, including carbon corrosion and PTFE loss, affects water management, conductivity and mass transport. GDLs were subjected to accelerated stress tests by immersing them in Fenton's reagent for 24 hours. Analysis of hydrophobic properties through contact angle measurements, thermogravimetry, and energy dispersive X-ray spectroscopy indicated that the hydrophobicity of the GDL exposed to Fenton's reagent decreased. This loss of hydrophobicity is associated with surface oxidation and PTFE degradation.
{"title":"Investigation of Gas Diffusion Layer Degradation in Polymer Electrolyte Fuel Cell Via Chemical Oxidation","authors":"Joel Mata Edjokola, Viktor Hacker, Merit Bodner","doi":"10.1149/11204.0265ecst","DOIUrl":"https://doi.org/10.1149/11204.0265ecst","url":null,"abstract":"The gas diffusion layer (GDL) enables and influences the internal transport of fuel, oxygen, electricity, heat and water. The GDL is made up of the macroporous substrate and the microporous layer. To achieve the hydrophobicity required for water management, the two layers are typically treated with polytetrafluoroethylene (PTFE). Degradation of GDL, including carbon corrosion and PTFE loss, affects water management, conductivity and mass transport. GDLs were subjected to accelerated stress tests by immersing them in Fenton's reagent for 24 hours. Analysis of hydrophobic properties through contact angle measurements, thermogravimetry, and energy dispersive X-ray spectroscopy indicated that the hydrophobicity of the GDL exposed to Fenton's reagent decreased. This loss of hydrophobicity is associated with surface oxidation and PTFE degradation.","PeriodicalId":11473,"journal":{"name":"ECS Transactions","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135243675","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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