Electric baseboard heaters have been widely used to provide convenient and economical heating in residential rooms. For old heaters that were installed many years ago, a secondary enclosure can be installed to cover the old heater for aesthetic and preventing scalding by the hot elements. The enclosure increases the thermal resistance for heating, which results in high temperature on the top surface of the enclosure. There is a significant lack of the information and work on the thermal design of enclosure for electric baseboard heaters. Developing an effective enclosure design that is able to keep the surface temperature within safe-to-touch range is the objective of this research. In this project, computational fluid dynamics simulation using COMSOL Multiphysics is the major methodology. Three approaches are taken to develop the new enclosure design. The first approach is to change material’s thermal properties: thermal conductivity, surface emissivity. It was found that the surface temperature decreased with reducing the thermal conductivity of the material. Moreover, the surface temperature can be effectively reduced by using the high surface emissivity coating material on the outer surface and the low surface emissivity coating material on the inner surface. The second approach is to modify mechanical design to facilitate air flow. It was discovered that increasing the openings for air inlet and outlet can effectively reduce the surface temperature. The third approach is to use thermoelectric fan to provide passively-powered forced convection heat transfer. It was found that the thermoelectric fan can be used to not only enhance the airflow through the heater but also to reduce the top surface temperature of the enclosure. The three approaches will be combined to develop effective and safe enclosures for electric baseboard heaters.
{"title":"Thermal Design Of Enclosure For Electric Baseboard Heaters","authors":"Ruoyao Li, Ri Li","doi":"10.32393/csme.2021.121","DOIUrl":"https://doi.org/10.32393/csme.2021.121","url":null,"abstract":"Electric baseboard heaters have been widely used to provide convenient and economical heating in residential rooms. For old heaters that were installed many years ago, a secondary enclosure can be installed to cover the old heater for aesthetic and preventing scalding by the hot elements. The enclosure increases the thermal resistance for heating, which results in high temperature on the top surface of the enclosure. There is a significant lack of the information and work on the thermal design of enclosure for electric baseboard heaters. Developing an effective enclosure design that is able to keep the surface temperature within safe-to-touch range is the objective of this research. In this project, computational fluid dynamics simulation using COMSOL Multiphysics is the major methodology. Three approaches are taken to develop the new enclosure design. The first approach is to change material’s thermal properties: thermal conductivity, surface emissivity. It was found that the surface temperature decreased with reducing the thermal conductivity of the material. Moreover, the surface temperature can be effectively reduced by using the high surface emissivity coating material on the outer surface and the low surface emissivity coating material on the inner surface. The second approach is to modify mechanical design to facilitate air flow. It was discovered that increasing the openings for air inlet and outlet can effectively reduce the surface temperature. The third approach is to use thermoelectric fan to provide passively-powered forced convection heat transfer. It was found that the thermoelectric fan can be used to not only enhance the airflow through the heater but also to reduce the top surface temperature of the enclosure. The three approaches will be combined to develop effective and safe enclosures for electric baseboard heaters.","PeriodicalId":446767,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 4","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132633956","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}
{"title":"Mechanically Induced Structural Adaptations Of Cranial Sutures","authors":"T. Khurelbaatar, M. Doschak, D. Romanyk","doi":"10.32393/csme.2021.103","DOIUrl":"https://doi.org/10.32393/csme.2021.103","url":null,"abstract":"","PeriodicalId":446767,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 4","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115462102","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}
{"title":"Parameter Estimation Of Groundwater Virus Transport Using Deep Neural Network","authors":"M. Shamsuzzaman, M. Satish","doi":"10.32393/csme.2021.125","DOIUrl":"https://doi.org/10.32393/csme.2021.125","url":null,"abstract":"","PeriodicalId":446767,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 4","volume":"241 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115600274","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}
{"title":"Design Optimization Of Autonomous Steering Control Schemes For Articulated Vehicles","authors":"Jiangtao Yu, Tarun Sharma, Yuping He","doi":"10.32393/csme.2021.215","DOIUrl":"https://doi.org/10.32393/csme.2021.215","url":null,"abstract":"","PeriodicalId":446767,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 4","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115118786","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}
Extracting hydrogen from nature is an arduous and energy intensive process and the challenge is aggravated as most of the current H2 production methods are not eco-friendly. A promising alternative is the copper-chlorine (Cu-Cl) cycle in which the constituents are recycled internally on continuous basis without emitting pollutants into the atmosphere. The Cu-Cl cycle is one of the hydrogen (H2) production methods, in which cuprous chloride (CuCl) salt is cooled down from 500 °C to 80 °C and reacted with hydrochloric acid (HCl) in stoichiometric proportions to produce the anolyte for the H2 production step of the cycle. This paper focuses on enhancing the overall thermal efficiency of the Cu-Cl cycle by recovering heat from molten CuCl salt, the output of one of the cycle’s three reactors. It has been determined that approximately 350 kJ of waste heat energy can be recovered during the production of 1kg of hydrogen. A novel numerical method is adopted to analyze the quenching process to estimate the heat that could be recovered and the temperature distribution of the CuCl droplet with its surroundings at different timesteps. The interactions between droplets with the nitrogen (N2) are modeled numerically in COMSOL Multiphysics for various droplet sizes of CuCl and silver chloride (AgCl), as the droplets are cooling, and the salts are changing phase from molten to solid. The heat recovery analysis shows that the average internal temperature of the droplet does not change significantly with droplet diameter and quenching height. To validate the results the heat distribution around a droplet of AgCl has been modelled since the thermophysical properties of AgCl are widely available. As a result of this study it has been determined that the heat transfer rates are significantly higher for AgCl compared to CuCl for identical droplet diameters since AgCl has higher thermal diffusivity.
{"title":"Numerical Thermal Model Of Liquid-To-Solid Phase Change Of Free Falling Cucl And Agcl Droplets","authors":"B. Rajasekaran, O. Jianu","doi":"10.32393/csme.2021.152","DOIUrl":"https://doi.org/10.32393/csme.2021.152","url":null,"abstract":"Extracting hydrogen from nature is an arduous and energy intensive process and the challenge is aggravated as most of the current H2 production methods are not eco-friendly. A promising alternative is the copper-chlorine (Cu-Cl) cycle in which the constituents are recycled internally on continuous basis without emitting pollutants into the atmosphere. The Cu-Cl cycle is one of the hydrogen (H2) production methods, in which cuprous chloride (CuCl) salt is cooled down from 500 °C to 80 °C and reacted with hydrochloric acid (HCl) in stoichiometric proportions to produce the anolyte for the H2 production step of the cycle. This paper focuses on enhancing the overall thermal efficiency of the Cu-Cl cycle by recovering heat from molten CuCl salt, the output of one of the cycle’s three reactors. It has been determined that approximately 350 kJ of waste heat energy can be recovered during the production of 1kg of hydrogen. A novel numerical method is adopted to analyze the quenching process to estimate the heat that could be recovered and the temperature distribution of the CuCl droplet with its surroundings at different timesteps. The interactions between droplets with the nitrogen (N2) are modeled numerically in COMSOL Multiphysics for various droplet sizes of CuCl and silver chloride (AgCl), as the droplets are cooling, and the salts are changing phase from molten to solid. The heat recovery analysis shows that the average internal temperature of the droplet does not change significantly with droplet diameter and quenching height. To validate the results the heat distribution around a droplet of AgCl has been modelled since the thermophysical properties of AgCl are widely available. As a result of this study it has been determined that the heat transfer rates are significantly higher for AgCl compared to CuCl for identical droplet diameters since AgCl has higher thermal diffusivity.","PeriodicalId":446767,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 4","volume":"156 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123897329","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}
{"title":"Free-Standing Thin Film Using Reduced Graphene Oxide With Low Sheet Resistance","authors":"Fangyan Sun, S. Sivoththaman, Z. Tan","doi":"10.32393/csme.2021.4","DOIUrl":"https://doi.org/10.32393/csme.2021.4","url":null,"abstract":"","PeriodicalId":446767,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 4","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123971108","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}
L. Morrissey, O. Tucker, R. Killen, D. Savin, D. Domingue, S. Nakhla
{"title":"Simulating Ion Irradiation Of Surfaces","authors":"L. Morrissey, O. Tucker, R. Killen, D. Savin, D. Domingue, S. Nakhla","doi":"10.32393/csme.2021.60","DOIUrl":"https://doi.org/10.32393/csme.2021.60","url":null,"abstract":"","PeriodicalId":446767,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 4","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125944405","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 paper, we study mechanics of bubbles in a yield stress fluid. This scenario can be found in a wide range of industrial and natural settings including natural and man-made ponds, oil well drilling and well-control applications, and nuclear waste storage. The original motivation of the study stems from relevant observations in oil sands tailings ponds. Recent studies indicate that anaerobic microorganisms contribute to the degradation of naphtha hydrocarbons and naphthenic acids in the FFT/MFT layers of oil sands tailings ponds, which leads to methane emissions from the ponds. The FFT and MFT layers are colloidal suspensions, which behave like viscoplastic fluids with time-dependent rheology: changing both with age and depth in the pond. The key feature of a viscoplastic fluid is its yield stress: the material flows only if the imposed stress exceeds the yield stress. This raises questions regarding the stability of bubbles that are trapped in a yield stress fluid, that we try to answer in this research through a series of targeted experiments. A vacuum chamber system was used to control the concentration and size of bubbles trapped in the fluid. A series of experiments have been performed to investigate the stability of both bubble clouds, and a single bubble. Our results show that the rheology of the material as well as interaction between bubbles affect the onset of motion significantly. According to our findings, a single bubble starts to rise in a solution with higher polymer concentration, i.e. higher yield stress and elastic modulus, at a larger size and with a larger aspect ratio. Furthermore, our results confirm that bubble clouds become unstable at a smaller bubble size in comparison with that of a single bubble. We believe this is related to the interaction of stress fields around the bubbles. To further clarify this point, we extend our study by looking at more fundamental scenarios, i.e. two or three bubbles at different orientations and separation distances. We examine this problem using both an experimental and a numerical approach to demonstrate how the stress fields around neighbouring bubbles interfere with each other and how this affects their onset of motion in a yield stress fluid. Acknowledgement This research was made possible by funding from NSERC and COSIA/IOSI (project numbers CRDPJ 537806-18 and IOSI Project #2018-10).
{"title":"Mechanics Of Bubbles In A Yield Stress Fluid","authors":"M. Daneshi, Miguel Eagleton, M. Zare, I. Frigaard","doi":"10.32393/csme.2021.9","DOIUrl":"https://doi.org/10.32393/csme.2021.9","url":null,"abstract":"In this paper, we study mechanics of bubbles in a yield stress fluid. This scenario can be found in a wide range of industrial and natural settings including natural and man-made ponds, oil well drilling and well-control applications, and nuclear waste storage. The original motivation of the study stems from relevant observations in oil sands tailings ponds. Recent studies indicate that anaerobic microorganisms contribute to the degradation of naphtha hydrocarbons and naphthenic acids in the FFT/MFT layers of oil sands tailings ponds, which leads to methane emissions from the ponds. The FFT and MFT layers are colloidal suspensions, which behave like viscoplastic fluids with time-dependent rheology: changing both with age and depth in the pond. The key feature of a viscoplastic fluid is its yield stress: the material flows only if the imposed stress exceeds the yield stress. This raises questions regarding the stability of bubbles that are trapped in a yield stress fluid, that we try to answer in this research through a series of targeted experiments. A vacuum chamber system was used to control the concentration and size of bubbles trapped in the fluid. A series of experiments have been performed to investigate the stability of both bubble clouds, and a single bubble. Our results show that the rheology of the material as well as interaction between bubbles affect the onset of motion significantly. According to our findings, a single bubble starts to rise in a solution with higher polymer concentration, i.e. higher yield stress and elastic modulus, at a larger size and with a larger aspect ratio. Furthermore, our results confirm that bubble clouds become unstable at a smaller bubble size in comparison with that of a single bubble. We believe this is related to the interaction of stress fields around the bubbles. To further clarify this point, we extend our study by looking at more fundamental scenarios, i.e. two or three bubbles at different orientations and separation distances. We examine this problem using both an experimental and a numerical approach to demonstrate how the stress fields around neighbouring bubbles interfere with each other and how this affects their onset of motion in a yield stress fluid. Acknowledgement This research was made possible by funding from NSERC and COSIA/IOSI (project numbers CRDPJ 537806-18 and IOSI Project #2018-10).","PeriodicalId":446767,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 4","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124697629","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}
Kenneth Hukpati, Ali Eliasu, S. Boakye-Yiadom, A. Czekanski
316L stainless steel alloy is widely used in hostile environments structural components due to attractive mechanical properties including good corrosion resistance and exceptional strength at high temperatures. The emergence of 3D-printing provides flexibility of 316L stainless steel alloy parts for various structural applications. A decent mix of metal powders, a combination of special printing parameters and printing orientation are however needed to improve the properties of the 3D-printed parts. Therefore, in the current studies, the effect of printing parameters and the build orientation on the microstructure and high strain rate properties of 3D-printed 316L stainless steel alloy was investigated. Printing parameters such as hatch spacing, laser power, scan speed as well as build direction have effect on the high strain rate compressive properties and microstructure of 316L stainless steel alloy. The microstructure will be characterized utilizing Optical Microscopy (OM) and Scanning Electron Microscopy (SEM) for final printed samples. Direct Impact Hopkinson Pressure Bar (DIHPB) will be used to examine the high strain rate deformation and failure modes. The microstructure of the samples was further characterized with Optical Microscopy (OM) and Scanning Electron Microscopy (SEM) post impact.
{"title":"Effect Of Printing Parameters On The High Strain Rate Compressive Behaviour Of Additively Manufactured 316L Stainless Steel Alloy","authors":"Kenneth Hukpati, Ali Eliasu, S. Boakye-Yiadom, A. Czekanski","doi":"10.32393/csme.2021.216","DOIUrl":"https://doi.org/10.32393/csme.2021.216","url":null,"abstract":"316L stainless steel alloy is widely used in hostile environments structural components due to attractive mechanical properties including good corrosion resistance and exceptional strength at high temperatures. The emergence of 3D-printing provides flexibility of 316L stainless steel alloy parts for various structural applications. A decent mix of metal powders, a combination of special printing parameters and printing orientation are however needed to improve the properties of the 3D-printed parts. Therefore, in the current studies, the effect of printing parameters and the build orientation on the microstructure and high strain rate properties of 3D-printed 316L stainless steel alloy was investigated. Printing parameters such as hatch spacing, laser power, scan speed as well as build direction have effect on the high strain rate compressive properties and microstructure of 316L stainless steel alloy. The microstructure will be characterized utilizing Optical Microscopy (OM) and Scanning Electron Microscopy (SEM) for final printed samples. Direct Impact Hopkinson Pressure Bar (DIHPB) will be used to examine the high strain rate deformation and failure modes. The microstructure of the samples was further characterized with Optical Microscopy (OM) and Scanning Electron Microscopy (SEM) post impact.","PeriodicalId":446767,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 4","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129869575","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 RADSAT-SK CubeSat project is a joint venture between The University of Saskatchewan, Saskatchewan Polytechnic, and the University of Saskatchewan Space Design Team. Funded in part by the Canadian Space Agency through the Canadian CubeSat Project, the RADSAT-SK satellite aims to fulfill research and educational objectives. The RADSAT-SK satellite carries three payloads on board. The first is a remote sensing optical payload which will capture grayscale images of the Earth to be used for outreach purposes stemming from the project. The second payload uses a novel method for monitoring the total dosage of radiation the satellite experiences using floating gate MOSFET devices. Lastly, the third payload is a novel method of blocking radiation by covering electronic components in compounds containing high concentrations of the amino-acid melanin. From the inception of the project, the RADSAT-SK project has been unique in that it is the only fully-student designed CubeSat in Canada, aside from faculty oversight regarding project finances and advice on management. The team currently consists of one faculty supervisor serving as the project’s principal investigator, and approximately 70 students, over 90% of whom are undergraduates. This unique team composition has led to the development of a project management structure in which students (largely undergraduates) are responsible for all aspects of the project. This structure has proven to be successful for RADSAT-SK, however the lack of experienced graduate students or extra faculty supervisors does pose a risk to project success as team member turnover is high, and undergraduate students are often not knowledgeable about the complexities relating to space mission designs. To mitigate this risk, the RADSAT-SK team has chosen a leadership structure where three project managers (technology, finance, HR/outreach) oversee seven team-leads who each individually manage one subsystem of the satellite. This structure has proven to have two benefits. The first is that executive members can remain focused on one specific subsystem
{"title":"Project Management Structure of a Fully Student Designed Cube-Satellite","authors":"Christopher Elash, S. Maw, Christoper A Amaya","doi":"10.32393/csme.2021.238","DOIUrl":"https://doi.org/10.32393/csme.2021.238","url":null,"abstract":"The RADSAT-SK CubeSat project is a joint venture between The University of Saskatchewan, Saskatchewan Polytechnic, and the University of Saskatchewan Space Design Team. Funded in part by the Canadian Space Agency through the Canadian CubeSat Project, the RADSAT-SK satellite aims to fulfill research and educational objectives. The RADSAT-SK satellite carries three payloads on board. The first is a remote sensing optical payload which will capture grayscale images of the Earth to be used for outreach purposes stemming from the project. The second payload uses a novel method for monitoring the total dosage of radiation the satellite experiences using floating gate MOSFET devices. Lastly, the third payload is a novel method of blocking radiation by covering electronic components in compounds containing high concentrations of the amino-acid melanin. From the inception of the project, the RADSAT-SK project has been unique in that it is the only fully-student designed CubeSat in Canada, aside from faculty oversight regarding project finances and advice on management. The team currently consists of one faculty supervisor serving as the project’s principal investigator, and approximately 70 students, over 90% of whom are undergraduates. This unique team composition has led to the development of a project management structure in which students (largely undergraduates) are responsible for all aspects of the project. This structure has proven to be successful for RADSAT-SK, however the lack of experienced graduate students or extra faculty supervisors does pose a risk to project success as team member turnover is high, and undergraduate students are often not knowledgeable about the complexities relating to space mission designs. To mitigate this risk, the RADSAT-SK team has chosen a leadership structure where three project managers (technology, finance, HR/outreach) oversee seven team-leads who each individually manage one subsystem of the satellite. This structure has proven to have two benefits. The first is that executive members can remain focused on one specific subsystem","PeriodicalId":446767,"journal":{"name":"Progress in Canadian Mechanical Engineering. Volume 4","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127425828","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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