Pub Date : 1996-08-19DOI: 10.1109/ISEMC.1996.561220
K. Liu
It has been known that air gaps between ferrite tiles degrade the absorbing performance of the tile absorber wall installation. However, analysis of the effect has not been thoroughly well published. This paper presents two techniques to analyze gaps between ferrite tiles. A simplified magnetic circuit method is introduced to calculate the effective permeability of the tile wall with gaps. Then, a two-dimensional finite element method is used to analyze the same gap model to validate the simplified formula. The air gap formula is then incorporated into characterizing the ferrite tile absorber with or without a dielectric absorber as its matching element. The fully characterized ferrite absorbers can then be used to design EMC chambers. Design examples are, presented to demonstrate the correlation between calculated and measured normalized site attenuations for 10 m/3 m EMC semi-anechoic chambers.
众所周知，铁氧体瓦片之间的气隙降低了瓦片吸收器墙体装置的吸收性能。然而，对这种影响的分析还没有得到充分的发表。本文介绍了两种分析铁氧体瓦间隙的方法。介绍了一种简化的磁路法来计算有空隙的砖瓦墙体的有效磁导率。然后，采用二维有限元法对同一间隙模型进行了分析，验证了简化公式的正确性。然后将气隙公式纳入表征具有或不具有电介质吸收体作为其匹配元件的铁氧体瓦吸收体。充分表征的铁氧体吸收体可用于设计电磁兼容腔。文中给出了设计实例，以证明10 m/3 m EMC半消声室的归一化站点衰减的计算值与实测值之间的相关性。
{"title":"Analysis of the effect of ferrite tile gap on EMC chamber having ferrite absorber walls","authors":"K. Liu","doi":"10.1109/ISEMC.1996.561220","DOIUrl":"https://doi.org/10.1109/ISEMC.1996.561220","url":null,"abstract":"It has been known that air gaps between ferrite tiles degrade the absorbing performance of the tile absorber wall installation. However, analysis of the effect has not been thoroughly well published. This paper presents two techniques to analyze gaps between ferrite tiles. A simplified magnetic circuit method is introduced to calculate the effective permeability of the tile wall with gaps. Then, a two-dimensional finite element method is used to analyze the same gap model to validate the simplified formula. The air gap formula is then incorporated into characterizing the ferrite tile absorber with or without a dielectric absorber as its matching element. The fully characterized ferrite absorbers can then be used to design EMC chambers. Design examples are, presented to demonstrate the correlation between calculated and measured normalized site attenuations for 10 m/3 m EMC semi-anechoic chambers.","PeriodicalId":296175,"journal":{"name":"Proceedings of Symposium on Electromagnetic Compatibility","volume":"205 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122601711","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 : 1996-08-19DOI: 10.1109/ISEMC.1996.561424
S. Wakamatsu, F. Tilley, G. Hubers, Y. Sakamoto, T. Kaneko, H. Yamamoto, Y. Karokawa
With recent advances in telecommunications using GHz range communication technologies, it is necessary to ensure product immunity from high frequency radio waves. Conventionally, shielding and/or feed through capacitors have been used to suppress EMI noise in the GHz range. However, this method has difficulties since a feed through capacitor must be mounted in a metal plate or equivalent. Although surface mount ferrite beads are simple to mount, their performance is limited in the GHz range. Newly developed EMI filters which have improved performance in the GHz range and are able to be mounted without a shielding case are examined. The new EMI filters improve the noise suppression by approximately 20 dB around 1 GHz as compare to conventional EMI filters. Evaluations using actual equipment illustrate the superior performance of the new EMI filters as compared to conventional filters such as surface mount ferrite beads. These new EMI filters are expected to ensure product immunity from radio waves at frequencies greater than 1 GHz.
{"title":"To reinforce immunities around GHz frequencies by EMI noise suppression filters","authors":"S. Wakamatsu, F. Tilley, G. Hubers, Y. Sakamoto, T. Kaneko, H. Yamamoto, Y. Karokawa","doi":"10.1109/ISEMC.1996.561424","DOIUrl":"https://doi.org/10.1109/ISEMC.1996.561424","url":null,"abstract":"With recent advances in telecommunications using GHz range communication technologies, it is necessary to ensure product immunity from high frequency radio waves. Conventionally, shielding and/or feed through capacitors have been used to suppress EMI noise in the GHz range. However, this method has difficulties since a feed through capacitor must be mounted in a metal plate or equivalent. Although surface mount ferrite beads are simple to mount, their performance is limited in the GHz range. Newly developed EMI filters which have improved performance in the GHz range and are able to be mounted without a shielding case are examined. The new EMI filters improve the noise suppression by approximately 20 dB around 1 GHz as compare to conventional EMI filters. Evaluations using actual equipment illustrate the superior performance of the new EMI filters as compared to conventional filters such as surface mount ferrite beads. These new EMI filters are expected to ensure product immunity from radio waves at frequencies greater than 1 GHz.","PeriodicalId":296175,"journal":{"name":"Proceedings of Symposium on Electromagnetic Compatibility","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125247557","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 : 1996-08-19DOI: 10.1109/ISEMC.1996.561225
D. Kempf
Electromagnetic vulnerability (EMV) testing is typically performed on aircraft using a standard method where the aircraft is directly radiated by an antenna, with no mode-stirring. Since a standing wave pattern will cause peaks and nulls in the field inside the aircraft, many antenna aspect angles should be used to assure that all equipment on board the aircraft is exposed to the appropriate field. However, this is very time consuming and often not feasible. As a result, some equipment on the aircraft may not be exposed to the intended field level. Using mode-stirred techniques during EMV testing will provide improvement in the field distribution throughout the aircraft so that the need to use several aspect angles would be eliminated, and a more controlled and thorough test would result. This study was performed to demonstrate this, by comparing cable coupling and field level measurements on a P-3 and an E-2C during EMV testing using both the standard method and mode-stirring.
{"title":"EMV testing of aircraft: a comparison of the mode-stirred and standard methods","authors":"D. Kempf","doi":"10.1109/ISEMC.1996.561225","DOIUrl":"https://doi.org/10.1109/ISEMC.1996.561225","url":null,"abstract":"Electromagnetic vulnerability (EMV) testing is typically performed on aircraft using a standard method where the aircraft is directly radiated by an antenna, with no mode-stirring. Since a standing wave pattern will cause peaks and nulls in the field inside the aircraft, many antenna aspect angles should be used to assure that all equipment on board the aircraft is exposed to the appropriate field. However, this is very time consuming and often not feasible. As a result, some equipment on the aircraft may not be exposed to the intended field level. Using mode-stirred techniques during EMV testing will provide improvement in the field distribution throughout the aircraft so that the need to use several aspect angles would be eliminated, and a more controlled and thorough test would result. This study was performed to demonstrate this, by comparing cable coupling and field level measurements on a P-3 and an E-2C during EMV testing using both the standard method and mode-stirring.","PeriodicalId":296175,"journal":{"name":"Proceedings of Symposium on Electromagnetic Compatibility","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132661095","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 : 1996-08-19DOI: 10.1109/ISEMC.1996.561246
F. Fiori, T. Foti, V. Pozzolo
In this work the modified Gummel Poon model (MGPM), implemented in the SPICE 3F4 simulator, is used to predict the effects of an RF disturbance in bipolar circuits. In fact in the presence of the conducted RF disturbances, the monodimensional models currently used for circuit simulations (Ebers Moll, Gummel Poon), cannot provide the behaviour of the device with sufficient accuracy. In particular, the modified SPICE 3F4 simulator has been used to predict BJT circuit susceptibility, performing .OP, .DC, .AC and .TRAN analysis, for the following interference signals: continuous wave (CW), amplitude modulated (AM) or frequency modulated (FM) disturbances, with carrier frequency in the range 100 MHz-1 GHz and RF power level up to 0 dBm.
{"title":"Computer aided analysis of RF effects in BJT circuits","authors":"F. Fiori, T. Foti, V. Pozzolo","doi":"10.1109/ISEMC.1996.561246","DOIUrl":"https://doi.org/10.1109/ISEMC.1996.561246","url":null,"abstract":"In this work the modified Gummel Poon model (MGPM), implemented in the SPICE 3F4 simulator, is used to predict the effects of an RF disturbance in bipolar circuits. In fact in the presence of the conducted RF disturbances, the monodimensional models currently used for circuit simulations (Ebers Moll, Gummel Poon), cannot provide the behaviour of the device with sufficient accuracy. In particular, the modified SPICE 3F4 simulator has been used to predict BJT circuit susceptibility, performing .OP, .DC, .AC and .TRAN analysis, for the following interference signals: continuous wave (CW), amplitude modulated (AM) or frequency modulated (FM) disturbances, with carrier frequency in the range 100 MHz-1 GHz and RF power level up to 0 dBm.","PeriodicalId":296175,"journal":{"name":"Proceedings of Symposium on Electromagnetic Compatibility","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131809703","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 : 1996-08-19DOI: 10.1109/ISEMC.1996.561202
J. Muccioli, T. M. North, K. Slattery
This study was initiated in order to gain a better understanding of the basis for using a 1 GHz TEM cell to evaluate the radiated emissions from integrated circuits (ICs). The authors have been involved for several years with the effort to develop procedures and standards for evaluating the EMC of ICs. One of these standards, SAE J1752/3, is being used by the IC industry to characterize high speed VLSI ICs and survey the variation of RF emissions due to changes in IC process and package parameters. This standard specifies a radiated emissions measurement system using a 1 GHz TEM cell with the IC under test on a test board that is a part of the wall above the septum of the TEM cell. In order to investigate the theoretical basis for this procedure, a model of the IC lead frame as a current loop was developed and analyzed for coupling to the septum of the TEM cell at different orientations. Test boards with current loops orientated both parallel and orthogonal to the TEM cell wall were evaluated for correlation with the model. Using a microprocessor on a test board, a comparison was made of the measured data from the 1 GHz TEM cell, the EMSCANTM circuit board analysis system and radiated field measurements using an antenna. Methods for calibration of the TEM cell were also investigated.
{"title":"Investigation of the theoretical basis for using a 1 GHz TEM cell to evaluate the radiated emissions from integrated circuits","authors":"J. Muccioli, T. M. North, K. Slattery","doi":"10.1109/ISEMC.1996.561202","DOIUrl":"https://doi.org/10.1109/ISEMC.1996.561202","url":null,"abstract":"This study was initiated in order to gain a better understanding of the basis for using a 1 GHz TEM cell to evaluate the radiated emissions from integrated circuits (ICs). The authors have been involved for several years with the effort to develop procedures and standards for evaluating the EMC of ICs. One of these standards, SAE J1752/3, is being used by the IC industry to characterize high speed VLSI ICs and survey the variation of RF emissions due to changes in IC process and package parameters. This standard specifies a radiated emissions measurement system using a 1 GHz TEM cell with the IC under test on a test board that is a part of the wall above the septum of the TEM cell. In order to investigate the theoretical basis for this procedure, a model of the IC lead frame as a current loop was developed and analyzed for coupling to the septum of the TEM cell at different orientations. Test boards with current loops orientated both parallel and orthogonal to the TEM cell wall were evaluated for correlation with the model. Using a microprocessor on a test board, a comparison was made of the measured data from the 1 GHz TEM cell, the EMSCANTM circuit board analysis system and radiated field measurements using an antenna. Methods for calibration of the TEM cell were also investigated.","PeriodicalId":296175,"journal":{"name":"Proceedings of Symposium on Electromagnetic Compatibility","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122896056","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 : 1996-08-19DOI: 10.1109/ISEMC.1996.561243
C. James, J. Norgard
The surface charge densities and associated capacitances of a shielded twisted pair transmission line are found for quasi static conditions, under balanced and longitudinal excitations. The unknown charge density is expanded in a Fourier series. The series is used as basis functions for a method of moments solution to find the unknown series coefficients. This paper describes the geometric structure and the formation of the integral equation that describes the potential distribution as a function of the unknown charge densities. The simplifying approximations made are pointed out, as well as the limitations to the solution caused by the approximations.
{"title":"Use of the method of moments to find the charge densities and capacitances of a shielded twisted pair transmission line","authors":"C. James, J. Norgard","doi":"10.1109/ISEMC.1996.561243","DOIUrl":"https://doi.org/10.1109/ISEMC.1996.561243","url":null,"abstract":"The surface charge densities and associated capacitances of a shielded twisted pair transmission line are found for quasi static conditions, under balanced and longitudinal excitations. The unknown charge density is expanded in a Fourier series. The series is used as basis functions for a method of moments solution to find the unknown series coefficients. This paper describes the geometric structure and the formation of the integral equation that describes the potential distribution as a function of the unknown charge densities. The simplifying approximations made are pointed out, as well as the limitations to the solution caused by the approximations.","PeriodicalId":296175,"journal":{"name":"Proceedings of Symposium on Electromagnetic Compatibility","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124040634","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 : 1996-08-19DOI: 10.1109/ISEMC.1996.561271
A. Mahinfallah, R. Nelson
The effects of an electrostatic discharge (ESD) event on a CMOS timing circuit were investigated experimentally and using computer simulations. Results are provided for cases when an ESD pulse was imposed on the original timing circuit, as well as when various protection schemes were incorporated in the circuit. Voltage spikes and timing errors were observed in the original timing circuit in both computer simulations and laboratory experiments. The beneficial effects of using ESD suppression devices were also observed in both cases. Similarities and differences between results obtained from computer simulations and laboratory experiments are discussed.
{"title":"Simulated and experimental effects of ESD on CMOS timing circuits","authors":"A. Mahinfallah, R. Nelson","doi":"10.1109/ISEMC.1996.561271","DOIUrl":"https://doi.org/10.1109/ISEMC.1996.561271","url":null,"abstract":"The effects of an electrostatic discharge (ESD) event on a CMOS timing circuit were investigated experimentally and using computer simulations. Results are provided for cases when an ESD pulse was imposed on the original timing circuit, as well as when various protection schemes were incorporated in the circuit. Voltage spikes and timing errors were observed in the original timing circuit in both computer simulations and laboratory experiments. The beneficial effects of using ESD suppression devices were also observed in both cases. Similarities and differences between results obtained from computer simulations and laboratory experiments are discussed.","PeriodicalId":296175,"journal":{"name":"Proceedings of Symposium on Electromagnetic Compatibility","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125654067","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 : 1996-08-19DOI: 10.1109/ISEMC.1996.561416
M. Schwerdt, J. Berger, K. Petermann
For the first time to our knowledge we present an E-field measurement of the tangential component |E/sub x/| in the near-field of a dipole antenna, using an integrated optical E-field sensor based on a Mach-Zehnder interferometer in lithium niobate (LiNbO/sub 3/). In comparison with conventional sensors the advantages of an integrated optical E-field sensor are the omission of metallic leads and the relatively small dimensions, resulting in reduced field perturbations. Due to the high substrate permittivity the sensor is well suited for measurements in liquids.
{"title":"E-field measurements in the near-field of transmitting antennas using an integrated electro-optical sensor","authors":"M. Schwerdt, J. Berger, K. Petermann","doi":"10.1109/ISEMC.1996.561416","DOIUrl":"https://doi.org/10.1109/ISEMC.1996.561416","url":null,"abstract":"For the first time to our knowledge we present an E-field measurement of the tangential component |E/sub x/| in the near-field of a dipole antenna, using an integrated optical E-field sensor based on a Mach-Zehnder interferometer in lithium niobate (LiNbO/sub 3/). In comparison with conventional sensors the advantages of an integrated optical E-field sensor are the omission of metallic leads and the relatively small dimensions, resulting in reduced field perturbations. Due to the high substrate permittivity the sensor is well suited for measurements in liquids.","PeriodicalId":296175,"journal":{"name":"Proceedings of Symposium on Electromagnetic Compatibility","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131152610","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 : 1996-08-19DOI: 10.1109/ISEMC.1996.561236
L. Kolb
There have been many attempts to assess the reproducibility of EMC measurements between test sites, with varying degrees of success dependent upon implementation details. Hewlett-Packard has a successful program of site-to-site reproducibility evaluations using a custom-designed RF source as a reference, and applying statistical techniques to include the day-to-day variability of each site in the collected data. Comparing the sites to the average (for lack of a reference site), 95% of the measurements agree within 3.8 dB between 30 and 100 MHz and between 550 and 1000 MHz, and within 2.8 dB between 100 and 550 MHz. The program benefits the participating sites by answering the question of how much variability can be expected from day to day and from that site to another, as well as detecting and helping to identify sources of measurement error. The paper also includes evidence that a 1/r correction going from 3 m to 10 m test distance involves errors of about 8 dB.
{"title":"Statistical comparison of site-to-site measurement reproducibility","authors":"L. Kolb","doi":"10.1109/ISEMC.1996.561236","DOIUrl":"https://doi.org/10.1109/ISEMC.1996.561236","url":null,"abstract":"There have been many attempts to assess the reproducibility of EMC measurements between test sites, with varying degrees of success dependent upon implementation details. Hewlett-Packard has a successful program of site-to-site reproducibility evaluations using a custom-designed RF source as a reference, and applying statistical techniques to include the day-to-day variability of each site in the collected data. Comparing the sites to the average (for lack of a reference site), 95% of the measurements agree within 3.8 dB between 30 and 100 MHz and between 550 and 1000 MHz, and within 2.8 dB between 100 and 550 MHz. The program benefits the participating sites by answering the question of how much variability can be expected from day to day and from that site to another, as well as detecting and helping to identify sources of measurement error. The paper also includes evidence that a 1/r correction going from 3 m to 10 m test distance involves errors of about 8 dB.","PeriodicalId":296175,"journal":{"name":"Proceedings of Symposium on Electromagnetic Compatibility","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133823874","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 : 1996-08-19DOI: 10.1109/ISEMC.1996.561259
S. M. Apollonskii
A shielding system for obtaining high "magnetic" vacuum is proposed, containing two conducting electric current ferromagnetic shells. Shells are located in each other with air interspaces. For an increase of homogeneity of residual fields in the shielded domain the displacement of the inner shell concerning the external shell (creation of an eccentricity) depends on the character of falling fields. A calculation method is given for a structure of shielding shells in a orthogonal curvilinear system of coordinates.
{"title":"Non-traditional methods of screening in electromagnetic systems","authors":"S. M. Apollonskii","doi":"10.1109/ISEMC.1996.561259","DOIUrl":"https://doi.org/10.1109/ISEMC.1996.561259","url":null,"abstract":"A shielding system for obtaining high \"magnetic\" vacuum is proposed, containing two conducting electric current ferromagnetic shells. Shells are located in each other with air interspaces. For an increase of homogeneity of residual fields in the shielded domain the displacement of the inner shell concerning the external shell (creation of an eccentricity) depends on the character of falling fields. A calculation method is given for a structure of shielding shells in a orthogonal curvilinear system of coordinates.","PeriodicalId":296175,"journal":{"name":"Proceedings of Symposium on Electromagnetic Compatibility","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132207704","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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