Pub Date : 2006-05-14DOI: 10.1109/MODSYM.2006.365258
H. Akiyama, S. Katsuki, T. Namihira, T. Sakugawa, H. Imamura
Development of the high power EUV (extreme ultraviolet) source has been expected as a light source for the next generation lithography. There are two kinds of EUV sources: the discharge produced plasma (DPP) and the laser produced plasma (LPP). The DPP method is considered to be promising in easiness of radiating the high power EUV and in the cheapness of constructing the EUV source. The Z- pinch plasmas driven by pulsed power have been used mainly in the DPP method. Here, the research results of the DPP method at Kumamoto University are summarized.
{"title":"Extreme Ultraviolet Radiation from Z-pinch Plasmas for Next Generation Lithography","authors":"H. Akiyama, S. Katsuki, T. Namihira, T. Sakugawa, H. Imamura","doi":"10.1109/MODSYM.2006.365258","DOIUrl":"https://doi.org/10.1109/MODSYM.2006.365258","url":null,"abstract":"Development of the high power EUV (extreme ultraviolet) source has been expected as a light source for the next generation lithography. There are two kinds of EUV sources: the discharge produced plasma (DPP) and the laser produced plasma (LPP). The DPP method is considered to be promising in easiness of radiating the high power EUV and in the cheapness of constructing the EUV source. The Z- pinch plasmas driven by pulsed power have been used mainly in the DPP method. Here, the research results of the DPP method at Kumamoto University are summarized.","PeriodicalId":410776,"journal":{"name":"Conference Record of the 2006 Twenty-Seventh International Power Modulator Symposium","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116241688","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 : 2006-05-14DOI: 10.1109/MODSYM.2006.365173
H. Bosman, W. Tang, Y. Lau, R. Gilgenbach
The heating of dielectric microwave transmission windows places an effective upper limit on the amount of power that may be transmitted through the window. Lossy surface films are known to form on diamond gyrotron windows, while thin films of TiN are intentionally deposited on alumina klystron windows to protect against multipactor. A uniform thin film of contaminant on a microwave window may absorb up to 50% of the incident power, even if the film thickness is only a small fraction of its resistive skin depth. Typical values for power losses due to surface films are on the order of 0.1%. This paper also provides the most general theoretical treatment to date on the degree of ohmic heating of discrete particulates by the rf electric field and the rf magnetic field of an electromagnetic wave, with the only assumption being that the wavelength is large in comparison with the particulate size. In general, heating by the rf magnetic field is dominant whenever the resistive skin depth is less than the radius of the particulate. The analysis may form a theoretical basis in the heating phenomenology of particulates
{"title":"Power Absorption by Dielectric Contaminants in High Power Microwave Systems","authors":"H. Bosman, W. Tang, Y. Lau, R. Gilgenbach","doi":"10.1109/MODSYM.2006.365173","DOIUrl":"https://doi.org/10.1109/MODSYM.2006.365173","url":null,"abstract":"The heating of dielectric microwave transmission windows places an effective upper limit on the amount of power that may be transmitted through the window. Lossy surface films are known to form on diamond gyrotron windows, while thin films of TiN are intentionally deposited on alumina klystron windows to protect against multipactor. A uniform thin film of contaminant on a microwave window may absorb up to 50% of the incident power, even if the film thickness is only a small fraction of its resistive skin depth. Typical values for power losses due to surface films are on the order of 0.1%. This paper also provides the most general theoretical treatment to date on the degree of ohmic heating of discrete particulates by the rf electric field and the rf magnetic field of an electromagnetic wave, with the only assumption being that the wavelength is large in comparison with the particulate size. In general, heating by the rf magnetic field is dominant whenever the resistive skin depth is less than the radius of the particulate. The analysis may form a theoretical basis in the heating phenomenology of particulates","PeriodicalId":410776,"journal":{"name":"Conference Record of the 2006 Twenty-Seventh International Power Modulator Symposium","volume":"409 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116526505","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 : 2006-05-14DOI: 10.1109/MODSYM.2006.365265
C. Vicente, A.M. Perez, Á. Coves, G. Torregrosa, C. Tienda, J.L. Gomez, F. Quesada, V. Boria, B. Gimeno, R. Barco, Alejandro Álvarez Melcón
In this paper, we present several results in two types of microwave components: coaxial waveguides and strip lines. Moreover, a deep theoretical investigation is shown for the case of a two parallel metal plates partially filled with a dielectric film. Relevant results are found both for coaxial lines operating in standing wave, and for the partially filled dielectric parallel plates in which the first crossover energies of the metal and the dielectric significantly differ.
{"title":"Multipactor Analysis in Microwave Components for High-Power Satellite Applications","authors":"C. Vicente, A.M. Perez, Á. Coves, G. Torregrosa, C. Tienda, J.L. Gomez, F. Quesada, V. Boria, B. Gimeno, R. Barco, Alejandro Álvarez Melcón","doi":"10.1109/MODSYM.2006.365265","DOIUrl":"https://doi.org/10.1109/MODSYM.2006.365265","url":null,"abstract":"In this paper, we present several results in two types of microwave components: coaxial waveguides and strip lines. Moreover, a deep theoretical investigation is shown for the case of a two parallel metal plates partially filled with a dielectric film. Relevant results are found both for coaxial lines operating in standing wave, and for the partially filled dielectric parallel plates in which the first crossover energies of the metal and the dielectric significantly differ.","PeriodicalId":410776,"journal":{"name":"Conference Record of the 2006 Twenty-Seventh International Power Modulator Symposium","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126286725","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 : 2006-05-14DOI: 10.1109/MODSYM.2006.365267
R. Burdt, R. Curry
Recent experiments have demonstrated the potential for transmission line transformers to be employed as high frequency, high power, pulsed oscillators operating in the 10 to 100 MHz regime at peak power levels on the order of 10 MW. Researchers at the University of Missouri-Columbia have fabricated and tested a prototype system that generates a 28 MW damped sinusoidal waveform over a 3-25 MHz spectrum into a 200 resistive load. A SPICE model has been developed to accurately model circuit behavior and scaling laws have been identified to allow for circuit design at higher frequencies and higher peak power
{"title":"A Novel High Frequency, High Power, Pulsed Oscillator Based on Transmission Line Transformer Technology","authors":"R. Burdt, R. Curry","doi":"10.1109/MODSYM.2006.365267","DOIUrl":"https://doi.org/10.1109/MODSYM.2006.365267","url":null,"abstract":"Recent experiments have demonstrated the potential for transmission line transformers to be employed as high frequency, high power, pulsed oscillators operating in the 10 to 100 MHz regime at peak power levels on the order of 10 MW. Researchers at the University of Missouri-Columbia have fabricated and tested a prototype system that generates a 28 MW damped sinusoidal waveform over a 3-25 MHz spectrum into a 200 resistive load. A SPICE model has been developed to accurately model circuit behavior and scaling laws have been identified to allow for circuit design at higher frequencies and higher peak power","PeriodicalId":410776,"journal":{"name":"Conference Record of the 2006 Twenty-Seventh International Power Modulator Symposium","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126839071","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 : 2006-05-14DOI: 10.1109/MODSYM.2006.365304
J. Zirnheld, S. Olabisi, P. Strzempka, A. Halstead, B. Urbanczyk, H. Moore
The exploding wire phenomenon is well researched due to its vast and practical applications which include, but are not limited to, shock wave generation, pulsed power, Z pinch physics, plasma ignition, fuses, and fusing applications. However, the focus of this research is on a surrogate for exploding wires. In this research, metallized capacitor grade-polypropylene film was used as an alternative for the traditional wire of a uniform diameter. The films that were studied have a broad variety of thicknesses ranging from 7 micron to 5 mil, lengths ranging from 5.08 cm to 19.05 cm, and sheet resistances of 1 ohm/square and 7 ohms/square. These films were used to study the effect of film properties on the transient plasma generation mechanism when exposed to a rapid high voltage discharge. The effect of these properties can be seen in the current waveform, similar to that of a uniform diameter exploding wire. By precisely understanding how the film properties affect the transient plasma formation, one can fine tune these variables to control the resulting characteristic pulse wave shape to fit a desired application.
{"title":"Effect of Substrate Thickness on Exploding Films","authors":"J. Zirnheld, S. Olabisi, P. Strzempka, A. Halstead, B. Urbanczyk, H. Moore","doi":"10.1109/MODSYM.2006.365304","DOIUrl":"https://doi.org/10.1109/MODSYM.2006.365304","url":null,"abstract":"The exploding wire phenomenon is well researched due to its vast and practical applications which include, but are not limited to, shock wave generation, pulsed power, Z pinch physics, plasma ignition, fuses, and fusing applications. However, the focus of this research is on a surrogate for exploding wires. In this research, metallized capacitor grade-polypropylene film was used as an alternative for the traditional wire of a uniform diameter. The films that were studied have a broad variety of thicknesses ranging from 7 micron to 5 mil, lengths ranging from 5.08 cm to 19.05 cm, and sheet resistances of 1 ohm/square and 7 ohms/square. These films were used to study the effect of film properties on the transient plasma generation mechanism when exposed to a rapid high voltage discharge. The effect of these properties can be seen in the current waveform, similar to that of a uniform diameter exploding wire. By precisely understanding how the film properties affect the transient plasma formation, one can fine tune these variables to control the resulting characteristic pulse wave shape to fit a desired application.","PeriodicalId":410776,"journal":{"name":"Conference Record of the 2006 Twenty-Seventh International Power Modulator Symposium","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126845892","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 : 2006-05-14DOI: 10.1109/MODSYM.2006.365190
L. Guangjie, Wang Jue, Y. Ping, Zhang Shichang, Sun Yaohong
The insulator strength of the oil-immersed equipment is usually limited by surface flashover across the oil-solid surface. At the same time, the distributions of failure strengths have some statistical characteristics. In this paper, the flashover voltage electric strengths of several PMMA test samples are measured in transformer oil under nanosecond pulse voltage. Normal distribution is introduced to describe the statistical characteristics of the experimental data. The plot of the flashover dielectric strength on Weibull paper can also demonstrates the two-parameter Weibull distribution. The parameters of the distributions are presented and the more favorable distribution is discussed with the view of obtaining consistent results for the surface dielectric strength
{"title":"Experimental Study on Statistical Characteristics of Surface Flashover under Nanosecond Pulse in Transformer Oil","authors":"L. Guangjie, Wang Jue, Y. Ping, Zhang Shichang, Sun Yaohong","doi":"10.1109/MODSYM.2006.365190","DOIUrl":"https://doi.org/10.1109/MODSYM.2006.365190","url":null,"abstract":"The insulator strength of the oil-immersed equipment is usually limited by surface flashover across the oil-solid surface. At the same time, the distributions of failure strengths have some statistical characteristics. In this paper, the flashover voltage electric strengths of several PMMA test samples are measured in transformer oil under nanosecond pulse voltage. Normal distribution is introduced to describe the statistical characteristics of the experimental data. The plot of the flashover dielectric strength on Weibull paper can also demonstrates the two-parameter Weibull distribution. The parameters of the distributions are presented and the more favorable distribution is discussed with the view of obtaining consistent results for the surface dielectric strength","PeriodicalId":410776,"journal":{"name":"Conference Record of the 2006 Twenty-Seventh International Power Modulator Symposium","volume":"154 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130676480","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 : 2006-05-14DOI: 10.1109/MODSYM.2006.365172
J. Verboncoeur, H.C. Kim, Y. Chen, Y. Lau
Plasma breakdown at dielectric windows the output of high power microwave systems has become an important challenge with the advent of GW power level sources. In this work, we report a number of recent advances which have significantly improved understanding of the physics of vacuum multipactors and gaseous discharges driven by microwaves, and in the parameter space and physics associated with the transition from one regime to the other
{"title":"Modeling RF Window Breakdown: From Vacuum Multipactor to Volumetric Ionization Discharge","authors":"J. Verboncoeur, H.C. Kim, Y. Chen, Y. Lau","doi":"10.1109/MODSYM.2006.365172","DOIUrl":"https://doi.org/10.1109/MODSYM.2006.365172","url":null,"abstract":"Plasma breakdown at dielectric windows the output of high power microwave systems has become an important challenge with the advent of GW power level sources. In this work, we report a number of recent advances which have significantly improved understanding of the physics of vacuum multipactors and gaseous discharges driven by microwaves, and in the parameter space and physics associated with the transition from one regime to the other","PeriodicalId":410776,"journal":{"name":"Conference Record of the 2006 Twenty-Seventh International Power Modulator Symposium","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134647595","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 : 2006-05-14DOI: 10.1109/MODSYM.2006.365204
A. Karabegovic, R. O’Connell
Class E amplifier theoretical efficiency is 100%, but the practical results at 10 GHz are much lower. In this paper, we propose a Class E amplifier that uses a photoswitch as active device instead of a transistor. The photoswitch opening and closing is controlled by light pulses. We used Silvaco software to do simulations of such an amplifier. Using this design, our best simulated efficiency at 10 GHz is 62.5%
{"title":"Photoswitch-Controlled Class E RF Power Amplifier","authors":"A. Karabegovic, R. O’Connell","doi":"10.1109/MODSYM.2006.365204","DOIUrl":"https://doi.org/10.1109/MODSYM.2006.365204","url":null,"abstract":"Class E amplifier theoretical efficiency is 100%, but the practical results at 10 GHz are much lower. In this paper, we propose a Class E amplifier that uses a photoswitch as active device instead of a transistor. The photoswitch opening and closing is controlled by light pulses. We used Silvaco software to do simulations of such an amplifier. Using this design, our best simulated efficiency at 10 GHz is 62.5%","PeriodicalId":410776,"journal":{"name":"Conference Record of the 2006 Twenty-Seventh International Power Modulator Symposium","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134037595","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 : 2006-05-14DOI: 10.1109/MODSYM.2006.365235
X. Lu, M. Laroussi
To shift the electron energy distribution function to high values in non-equilibrium plasmas, sub-microsecond high-voltage pulses have been used. Higher electron energies lead to an enhanced degree of ionization and excitation. In this paper, nanoseconds high-voltage pulses are used to drive a dielectric barrier discharge, one of the widely used methods to generate non-equilibrium, atmospheric pressure plasmas. To study the ignition process of the discharge and its structure, a high-speed ICCD camera was used. Using a 5 ns exposure time, photos showed that there are two separate discharges, referred to in this paper as the primary discharge and the secondary discharge. The first discharge starts from the bulk of the gap and the whole gap reaches its maximum emission intensity within 20 ns. Before the secondary discharge starts, there are weak emission layers next to both electrodes. The secondary discharge develops from the anode and expands towards the cathode, with the marked presence of a dark space adjacent to a weakly luminous cathode layer. Since the agents responsible for the efficient plasma reactivity are the ultraviolet (UV) photons and the chemically reactive species, the UV radiation and reactive species generation efficiency are also studied. The emission spectra shows that most of the UV is emitted by excited NO radicals, where the oxygen atoms come from residual trace amounts of air. In addition to NO and NO2 , excited N2, N2 +, OH, and He are also present in the plasma
{"title":"Homogeneous Dielectric Barrier Discharge in He/N2 Mixtures Driven by Unipolar Sub-microsecond Square Pulses","authors":"X. Lu, M. Laroussi","doi":"10.1109/MODSYM.2006.365235","DOIUrl":"https://doi.org/10.1109/MODSYM.2006.365235","url":null,"abstract":"To shift the electron energy distribution function to high values in non-equilibrium plasmas, sub-microsecond high-voltage pulses have been used. Higher electron energies lead to an enhanced degree of ionization and excitation. In this paper, nanoseconds high-voltage pulses are used to drive a dielectric barrier discharge, one of the widely used methods to generate non-equilibrium, atmospheric pressure plasmas. To study the ignition process of the discharge and its structure, a high-speed ICCD camera was used. Using a 5 ns exposure time, photos showed that there are two separate discharges, referred to in this paper as the primary discharge and the secondary discharge. The first discharge starts from the bulk of the gap and the whole gap reaches its maximum emission intensity within 20 ns. Before the secondary discharge starts, there are weak emission layers next to both electrodes. The secondary discharge develops from the anode and expands towards the cathode, with the marked presence of a dark space adjacent to a weakly luminous cathode layer. Since the agents responsible for the efficient plasma reactivity are the ultraviolet (UV) photons and the chemically reactive species, the UV radiation and reactive species generation efficiency are also studied. The emission spectra shows that most of the UV is emitted by excited NO radicals, where the oxygen atoms come from residual trace amounts of air. In addition to NO and NO2 , excited N2, N2 +, OH, and He are also present in the plasma","PeriodicalId":410776,"journal":{"name":"Conference Record of the 2006 Twenty-Seventh International Power Modulator Symposium","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122228708","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 : 2006-05-14DOI: 10.1109/MODSYM.2006.365231
Dennis Okula
In pulsed radar transmitters, the modulator is the key interface to the vacuum electronic device. Modern modulators use the series connection of semiconductors for high voltage switches. Stacked IGBTs are used for high current and low repetition rate applications, and stacked MOSFETs are used for low current and high repetition rate. For reliable operation, a series stacked switch needs to have voltage balance during static and dynamic conditions. One approach to achieve this balance is to use voltage grading resistors and capacitors. However, if poorly selected, this approach may have high power losses and not be compact. Because of the need for compact designs, this paper describes methods to equalize the voltage distribution for each switch. For MOSFET switches, this paper describes modulator design, protection, Miller effect, voltage balance due to parasitic capacitance, and thermal design. For reliable designs over large operating temperature ranges, this paper identifies the need for an integrated design that addresses all of the power losses in the switch and describes a metric for efficient designs, dissipation density ratio
{"title":"Series Stacked Switches for Radar Transmitters","authors":"Dennis Okula","doi":"10.1109/MODSYM.2006.365231","DOIUrl":"https://doi.org/10.1109/MODSYM.2006.365231","url":null,"abstract":"In pulsed radar transmitters, the modulator is the key interface to the vacuum electronic device. Modern modulators use the series connection of semiconductors for high voltage switches. Stacked IGBTs are used for high current and low repetition rate applications, and stacked MOSFETs are used for low current and high repetition rate. For reliable operation, a series stacked switch needs to have voltage balance during static and dynamic conditions. One approach to achieve this balance is to use voltage grading resistors and capacitors. However, if poorly selected, this approach may have high power losses and not be compact. Because of the need for compact designs, this paper describes methods to equalize the voltage distribution for each switch. For MOSFET switches, this paper describes modulator design, protection, Miller effect, voltage balance due to parasitic capacitance, and thermal design. For reliable designs over large operating temperature ranges, this paper identifies the need for an integrated design that addresses all of the power losses in the switch and describes a metric for efficient designs, dissipation density ratio","PeriodicalId":410776,"journal":{"name":"Conference Record of the 2006 Twenty-Seventh International Power Modulator Symposium","volume":"29 22-23","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114044099","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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