Pub Date : 2002-04-07DOI: 10.1109/ELINSL.2002.995911
P. Werle, A. Akbari, H. Borsi, E. Gockenbach
In this contribution different digital filtering algorithms, which use new approaches like the wavelet transform as well as a new introduced adaptive frequency rejection filter in the frequency domain, are investigated concerning their ability to suppress different kinds of noise as they appear during online partial discharge (PD) measurements on power transformers. Therefore various investigations on measured PD signals in the laboratory superimposed by synthetically generated noises have been performed leading to recommendations how different noise types can be efficiently suppressed.
{"title":"Enhanced online PD evaluation on power transformers using wavelet techniques and frequency rejection filter for noise suppression","authors":"P. Werle, A. Akbari, H. Borsi, E. Gockenbach","doi":"10.1109/ELINSL.2002.995911","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995911","url":null,"abstract":"In this contribution different digital filtering algorithms, which use new approaches like the wavelet transform as well as a new introduced adaptive frequency rejection filter in the frequency domain, are investigated concerning their ability to suppress different kinds of noise as they appear during online partial discharge (PD) measurements on power transformers. Therefore various investigations on measured PD signals in the laboratory superimposed by synthetically generated noises have been performed leading to recommendations how different noise types can be efficiently suppressed.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"33 1","pages":"195-198"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72943194","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 : 2002-04-07DOI: 10.1109/ELINSL.2002.995940
Peiping Wei, L. Dong, Shuyu Han, Xiaochun Chi, Jia-xiang Yang
In this paper a novel type of a water film corona discharge experiment model is designed. The reactor is composed of needle-plate electrodes that are placed in a glass container filled with the flue gas, (the plate electrode is immersed in the water). The mechanism of the formation of corona discharge in the pollution flue gas containing sulfur dioxide (SO/sub 2/) and nitrogen oxides (NO/sub x/) is investigated under the conditions that there are different concentration of sulfur dioxide and nitrogen oxides of the flue gas and different applied voltages. Based on this the emphasis is on studying the influence of water on corona discharge in flue gas. The experimental results show that the corona wind forming between high-voltage electrode and water film by corona discharge enhances the cleansing efficiency of the flue gas because of the existence of the water film, and the cleaning efficiency will increase with the increase of the voltage under a definite range of applied voltage. According to this effect a water film electrical corona reactor that we design is used to treat the flue gas of the boiler, and the result shows it not only makes the removal efficiency of dust up to 100%, but also makes about 98% of SO/sub 2/ and 85% of NO/sub x/ removal respectively under suitable conditions. This project is very significant for the prevention of acid rain and the treatment of dust of flue gas and the improvement on the traditional electrical dust precipitator.
{"title":"The influence of water on corona discharge in the flue gas","authors":"Peiping Wei, L. Dong, Shuyu Han, Xiaochun Chi, Jia-xiang Yang","doi":"10.1109/ELINSL.2002.995940","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995940","url":null,"abstract":"In this paper a novel type of a water film corona discharge experiment model is designed. The reactor is composed of needle-plate electrodes that are placed in a glass container filled with the flue gas, (the plate electrode is immersed in the water). The mechanism of the formation of corona discharge in the pollution flue gas containing sulfur dioxide (SO/sub 2/) and nitrogen oxides (NO/sub x/) is investigated under the conditions that there are different concentration of sulfur dioxide and nitrogen oxides of the flue gas and different applied voltages. Based on this the emphasis is on studying the influence of water on corona discharge in flue gas. The experimental results show that the corona wind forming between high-voltage electrode and water film by corona discharge enhances the cleansing efficiency of the flue gas because of the existence of the water film, and the cleaning efficiency will increase with the increase of the voltage under a definite range of applied voltage. According to this effect a water film electrical corona reactor that we design is used to treat the flue gas of the boiler, and the result shows it not only makes the removal efficiency of dust up to 100%, but also makes about 98% of SO/sub 2/ and 85% of NO/sub x/ removal respectively under suitable conditions. This project is very significant for the prevention of acid rain and the treatment of dust of flue gas and the improvement on the traditional electrical dust precipitator.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"44 1","pages":"317-319"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74328571","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 : 2002-04-07DOI: 10.1109/ELINSL.2002.995907
J. van Bolhuis, E. Gulski, J. Smit, D. Pepper
Much has been said about the reliability and interpretation of recovery voltage method (RVM) measurements. It has been shown in literature that the RVM method can be used to detect local moisture ingress in transformers, but also it has been shown that the old interpretation of the 'dominant time constant' has been found wanting. An important failure of the 'dominant time constant' interpretation is that it both focusses the user on a too simple interpretation and neglects data on other quantities that have also been recorded during this measurement. This paper deals with the all quantities that are recorded during an RVM measurement and shows how to use them so that they can form the basis of a better way to interpret RVM measurements.
{"title":"Interpretation of RVM measurements, beyond the polarisation spectrum","authors":"J. van Bolhuis, E. Gulski, J. Smit, D. Pepper","doi":"10.1109/ELINSL.2002.995907","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995907","url":null,"abstract":"Much has been said about the reliability and interpretation of recovery voltage method (RVM) measurements. It has been shown in literature that the RVM method can be used to detect local moisture ingress in transformers, but also it has been shown that the old interpretation of the 'dominant time constant' has been found wanting. An important failure of the 'dominant time constant' interpretation is that it both focusses the user on a too simple interpretation and neglects data on other quantities that have also been recorded during this measurement. This paper deals with the all quantities that are recorded during an RVM measurement and shows how to use them so that they can form the basis of a better way to interpret RVM measurements.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"57 1","pages":"179-182"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79805418","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 : 2002-04-07DOI: 10.1109/ELINSL.2002.995934
Yang Cao, S. Boggs
The effect of fluid impregnation in polyethylene is studied by electroluminescence using a semi-conducting polymer needle molded into a plaque sample. The threshold voltage for electroluminescence is measured for two impregnating fluids which do not impair semiconductor conductivity and is correlated with the soaking time. The mechanism of the dielectric improvement by liquid impregnation is discussed.
{"title":"Electroluminescence study of fluid-impregnated polymeric dielectric","authors":"Yang Cao, S. Boggs","doi":"10.1109/ELINSL.2002.995934","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995934","url":null,"abstract":"The effect of fluid impregnation in polyethylene is studied by electroluminescence using a semi-conducting polymer needle molded into a plaque sample. The threshold voltage for electroluminescence is measured for two impregnating fluids which do not impair semiconductor conductivity and is correlated with the soaking time. The mechanism of the dielectric improvement by liquid impregnation is discussed.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"31 1","pages":"294-297"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81644459","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 : 2002-04-07DOI: 10.1109/ELINSL.2002.995891
Z. Zheng, S. Boggs
Computation of partial discharge signal propagation along power cables with concentric neutral wires and ground plane is investigated. A distributed RLC network model of the cable is formed to simulate this phenomenon. The electromagnetic parameters of the power cable are calculated with a finite element method. Employing the three-line transmission theory, the waveform propagation in both time and frequency domain is formulated. Simulation results are presented and discussed.
{"title":"Partial discharge propagation in concentric neutral power cable over a ground plane","authors":"Z. Zheng, S. Boggs","doi":"10.1109/ELINSL.2002.995891","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995891","url":null,"abstract":"Computation of partial discharge signal propagation along power cables with concentric neutral wires and ground plane is investigated. A distributed RLC network model of the cable is formed to simulate this phenomenon. The electromagnetic parameters of the power cable are calculated with a finite element method. Employing the three-line transmission theory, the waveform propagation in both time and frequency domain is formulated. Simulation results are presented and discussed.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"22 1","pages":"104-107"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84600466","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 : 2002-04-07DOI: 10.1109/ELINSL.2002.995948
C. Krause, W. Goetz, B. Heinrich
This study reports on the effect of processing conditions on the static clamping force of transformer windings and on the variation of the clamping force with time. Small scale disc winding models were submitted to various drying and oil impregnation procedures, as well as different clamping and temperature conditions. The results confirm the importance of properly controlled processing parameters. Furthermore, the impact of time, and of temperature variation as they typically occur at load cycles, was investigated. Significant change of the clamping force was observed, which means that the static force deviated considerably from the value as set initially, prior to oil impregnation. Even within a short period of 10 days, a slight overall decrease of the clamping pressure was measured.
{"title":"The impact of drying and oil impregnation conditions and of temperature cycles on the clamping force of power transformer windings","authors":"C. Krause, W. Goetz, B. Heinrich","doi":"10.1109/ELINSL.2002.995948","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995948","url":null,"abstract":"This study reports on the effect of processing conditions on the static clamping force of transformer windings and on the variation of the clamping force with time. Small scale disc winding models were submitted to various drying and oil impregnation procedures, as well as different clamping and temperature conditions. The results confirm the importance of properly controlled processing parameters. Furthermore, the impact of time, and of temperature variation as they typically occur at load cycles, was investigated. Significant change of the clamping force was observed, which means that the static force deviated considerably from the value as set initially, prior to oil impregnation. Even within a short period of 10 days, a slight overall decrease of the clamping pressure was measured.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"9 1","pages":"350-353"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76745555","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 : 2002-04-07DOI: 10.1109/ELINSL.2002.995991
M. Dyer
Summary form only given, as follows. This paper investigates the "Mystery of the Corroding Switchgear" and provides an explanation of the cause. These results have been used by an electric utility to re-evaluate the service entrance cable requirements.
{"title":"Electrical cable loading and the degradation of PVC conduit","authors":"M. Dyer","doi":"10.1109/ELINSL.2002.995991","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995991","url":null,"abstract":"Summary form only given, as follows. This paper investigates the \"Mystery of the Corroding Switchgear\" and provides an explanation of the cause. These results have been used by an electric utility to re-evaluate the service entrance cable requirements.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"60 1","pages":"539-"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82141153","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 : 2002-04-07DOI: 10.1109/ELINSL.2002.995900
K. Raja, T. Floribert
This publication deals with UHF and acoustic partial discharge (PD) detection sensitivity assessment of paper/oil insulation configurations which are typical of power transformers. Even though the basis of this topic has been developed some time ago, the knowledge of the accuracy and limits of the sensitivity is of increasing importance for large power transformer test engineers who are confronted not only of reliable measurement of PD but also locating the source of discharges. Discharges representative of that occurring in a transformer were recorded by simulating them in a 220 kV test tank. The models simulated the basic insulation configuration of a transformer with multiple pressboard barriers and oil gaps. The influence of the effect of barriers on the sensitivity of UHF and acoustic PD detection were studied. Classical phase-resolved PD patterns were recorded alongside for analyzing the results of experiments. Experimental outcomes on these models were further verified on a 220 kV winding in a 400 kV test tank. Studies reveal that acoustic. sensitivity is seriously impaired by the presence of barriers, i.e. sensitivity of discharges shielded by insulating barriers is low as compared to those discharges in open oil volumes. For comparable distances, this sensitivity limitation is absent for UHF PD detection. Furthermore, merits and limits of individual methods are discussed that may lead to future research.
{"title":"Comparative investigations on UHF and acoustic PD detection sensitivity in transformers","authors":"K. Raja, T. Floribert","doi":"10.1109/ELINSL.2002.995900","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995900","url":null,"abstract":"This publication deals with UHF and acoustic partial discharge (PD) detection sensitivity assessment of paper/oil insulation configurations which are typical of power transformers. Even though the basis of this topic has been developed some time ago, the knowledge of the accuracy and limits of the sensitivity is of increasing importance for large power transformer test engineers who are confronted not only of reliable measurement of PD but also locating the source of discharges. Discharges representative of that occurring in a transformer were recorded by simulating them in a 220 kV test tank. The models simulated the basic insulation configuration of a transformer with multiple pressboard barriers and oil gaps. The influence of the effect of barriers on the sensitivity of UHF and acoustic PD detection were studied. Classical phase-resolved PD patterns were recorded alongside for analyzing the results of experiments. Experimental outcomes on these models were further verified on a 220 kV winding in a 400 kV test tank. Studies reveal that acoustic. sensitivity is seriously impaired by the presence of barriers, i.e. sensitivity of discharges shielded by insulating barriers is low as compared to those discharges in open oil volumes. For comparable distances, this sensitivity limitation is absent for UHF PD detection. Furthermore, merits and limits of individual methods are discussed that may lead to future research.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"46 1","pages":"150-153"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82145354","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 : 2002-04-07DOI: 10.1109/ELINSL.2002.995917
Nancy E. Frost, Krenceski
Silicone polymer-based high voltage insulators enjoy an inherent advantage in their rapid return to a hydrophobic surface after electrical discharge. This work describes a close scrutiny of the factors that influence the level of surface breakdown (corona discharge time, intensity, distance of application) as well as the subsequent evaluation of the recovery (contact angle measurement technique, operator). Six sigma tools were used to identify the factors influencing test results. A reproducibility and repeatability study identified the contribution of the equipment and operator to the test results. By controlling key instrument and test method parameters, it was possible to develop a novel analysis model to predict the time to return to hydrophobic behavior that is useful in formulation development testing.
{"title":"Hydrophobicity recovery in silicone insulators: a closer look at testing","authors":"Nancy E. Frost, Krenceski","doi":"10.1109/ELINSL.2002.995917","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995917","url":null,"abstract":"Silicone polymer-based high voltage insulators enjoy an inherent advantage in their rapid return to a hydrophobic surface after electrical discharge. This work describes a close scrutiny of the factors that influence the level of surface breakdown (corona discharge time, intensity, distance of application) as well as the subsequent evaluation of the recovery (contact angle measurement technique, operator). Six sigma tools were used to identify the factors influencing test results. A reproducibility and repeatability study identified the contribution of the equipment and operator to the test results. By controlling key instrument and test method parameters, it was possible to develop a novel analysis model to predict the time to return to hydrophobic behavior that is useful in formulation development testing.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"2007 1","pages":"220-223"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82482457","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 : 2002-04-07DOI: 10.1109/ELINSL.2002.995943
H. Gill, R. Doney, E.K. Althoff, W. J. Sarjeant
Very fast dV/dt pulsing influences the amount of subpicocoulomb microdischarges observed in reconstituted mica paper capacitors. These microdischarges are analyzed by means of a new aging diagnostic technique. This new approach involves the measurement of the microdischarge inception voltage-the point when microdischarges reach approximately 0.5 pC-and its dependence on the quantity and magnitude of high dV/dt stressing. Taking into account mica's robust nature in thermal environments, little effect from high dV/dt pulses is observed in the material. However, aging does occur at the electrode-mica interface. The Energy Systems Institute (ESI) has developed, over many years, research oriented diagnostic tools for measuring microdischarges on various materials. The Biddle Micro Discharge Analyzer (/spl mu/DA), developed at the ESI in conjunction with AVO-Biddle, accurately measures subpicocoulomb levels of charge on a sample up to at least 20 kV AC+DC. The Model-9 MIT Hard Tube Pulser (MOD-9) has been updated and improved to voltage stress various samples up to a megavolt per microsecond. The focus of this research combines the abilities of the Biddle /spl mu/DA, with the high dV/dt MOD-9 for looking into the relationship of insulation aging as a function of very fast voltage pulses. As more applications move to pulse power, specifically in the military, there is a critical need to evaluate the ability of certain dielectric materials to survive the transition from traditional DC and/or AC power to high rep-rate pulsed power.
{"title":"New aging diagnostics for microdischarge assessment of high dV/dt stressed mica paper capacitors","authors":"H. Gill, R. Doney, E.K. Althoff, W. J. Sarjeant","doi":"10.1109/ELINSL.2002.995943","DOIUrl":"https://doi.org/10.1109/ELINSL.2002.995943","url":null,"abstract":"Very fast dV/dt pulsing influences the amount of subpicocoulomb microdischarges observed in reconstituted mica paper capacitors. These microdischarges are analyzed by means of a new aging diagnostic technique. This new approach involves the measurement of the microdischarge inception voltage-the point when microdischarges reach approximately 0.5 pC-and its dependence on the quantity and magnitude of high dV/dt stressing. Taking into account mica's robust nature in thermal environments, little effect from high dV/dt pulses is observed in the material. However, aging does occur at the electrode-mica interface. The Energy Systems Institute (ESI) has developed, over many years, research oriented diagnostic tools for measuring microdischarges on various materials. The Biddle Micro Discharge Analyzer (/spl mu/DA), developed at the ESI in conjunction with AVO-Biddle, accurately measures subpicocoulomb levels of charge on a sample up to at least 20 kV AC+DC. The Model-9 MIT Hard Tube Pulser (MOD-9) has been updated and improved to voltage stress various samples up to a megavolt per microsecond. The focus of this research combines the abilities of the Biddle /spl mu/DA, with the high dV/dt MOD-9 for looking into the relationship of insulation aging as a function of very fast voltage pulses. As more applications move to pulse power, specifically in the military, there is a critical need to evaluate the ability of certain dielectric materials to survive the transition from traditional DC and/or AC power to high rep-rate pulsed power.","PeriodicalId":10532,"journal":{"name":"Conference Record of the the 2002 IEEE International Symposium on Electrical Insulation (Cat. No.02CH37316)","volume":"24 1","pages":"327-330"},"PeriodicalIF":0.0,"publicationDate":"2002-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82536324","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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