Pub Date : 1998-06-07DOI: 10.1109/BEAMS.1998.817001
A. Goncharov, I. Litovko, I. Protsenko
The magnetically insulated diode gap in the plasma optical mode (MDG) is a special case of the one-dimensional DG with magnetized electrons and free ions.
等离子体光模中磁绝缘二极管隙是一维等离子体光模中具有磁化电子和自由离子的特殊情况。
{"title":"Magnetically insulated ion diode in plasma optical mode","authors":"A. Goncharov, I. Litovko, I. Protsenko","doi":"10.1109/BEAMS.1998.817001","DOIUrl":"https://doi.org/10.1109/BEAMS.1998.817001","url":null,"abstract":"The magnetically insulated diode gap in the plasma optical mode (MDG) is a special case of the one-dimensional DG with magnetized electrons and free ions.","PeriodicalId":410823,"journal":{"name":"12th International Conference on High-Power Particle Beams. BEAMS'98. Proceedings (Cat. No.98EX103)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124281395","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 : 1998-06-07DOI: 10.1109/BEAMS.1998.822413
A. Gordeev, A.S. Chuvatin, H. Ghalila
In this paper, a simple theoretical model of the launched electrons (LE) equilibrium will be presented. The model allows simpler understanding of the nature of LE. It will be shown that appearance of the LE in the magnetic insulation transmission lines (MITL) gap may be preferable from the point of view of the minimum energy principle. PIC numerical simulations were also performed to investigate conditions under which the LE may appear.
{"title":"The launched electrons: simple theoretical modeling and numerical simulations","authors":"A. Gordeev, A.S. Chuvatin, H. Ghalila","doi":"10.1109/BEAMS.1998.822413","DOIUrl":"https://doi.org/10.1109/BEAMS.1998.822413","url":null,"abstract":"In this paper, a simple theoretical model of the launched electrons (LE) equilibrium will be presented. The model allows simpler understanding of the nature of LE. It will be shown that appearance of the LE in the magnetic insulation transmission lines (MITL) gap may be preferable from the point of view of the minimum energy principle. PIC numerical simulations were also performed to investigate conditions under which the LE may appear.","PeriodicalId":410823,"journal":{"name":"12th International Conference on High-Power Particle Beams. BEAMS'98. Proceedings (Cat. No.98EX103)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125101477","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 : 1998-06-07DOI: 10.1109/BEAMS.1998.822419
K. Masugata, E. Chishiro, K. Yatsui
The effect of the irradiation of leakage electrons on the anode is evaluated by using two types of different magnetic field geometry of an applied B, magnetically insulated diode. For the geometry of Type 1 where leakage electrons are is rare, the diode turns on with large delay time and the efficiency was worse. For Type 2 where initial electron irradiation of the anode occurs, the turn on delay was reduced and a high current density ion beam was obtained with higher efficiency. From the result we see that electron bombardment strongly promotes the production of an anode plasma on the flashboard. The characteristic of the magnetically insulated diode in a multi-shot operation is investigated. Ion current density (J/sub i/) decreases with increasing number of shots. The reduction of J/sub i/ is found to be mainly due to the accumulation of conductive stick matter on the flashboard.
{"title":"Characteristics of flashover ion sources in magnetically insulated ion diode","authors":"K. Masugata, E. Chishiro, K. Yatsui","doi":"10.1109/BEAMS.1998.822419","DOIUrl":"https://doi.org/10.1109/BEAMS.1998.822419","url":null,"abstract":"The effect of the irradiation of leakage electrons on the anode is evaluated by using two types of different magnetic field geometry of an applied B, magnetically insulated diode. For the geometry of Type 1 where leakage electrons are is rare, the diode turns on with large delay time and the efficiency was worse. For Type 2 where initial electron irradiation of the anode occurs, the turn on delay was reduced and a high current density ion beam was obtained with higher efficiency. From the result we see that electron bombardment strongly promotes the production of an anode plasma on the flashboard. The characteristic of the magnetically insulated diode in a multi-shot operation is investigated. Ion current density (J/sub i/) decreases with increasing number of shots. The reduction of J/sub i/ is found to be mainly due to the accumulation of conductive stick matter on the flashboard.","PeriodicalId":410823,"journal":{"name":"12th International Conference on High-Power Particle Beams. BEAMS'98. Proceedings (Cat. No.98EX103)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130127069","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 : 1998-06-07DOI: 10.1109/BEAMS.1998.822498
C. Munz, P. Omnes, R. Schneider, E. Sonnendrucker, E. Stein, U. Voß, T. Westermann
Pulsed-power diodes have been developed at the Forschungszentrum Karlsruhe and are the objects of extensive experimental as well as numerical investigations. The electrical behavior of the diodes is substantially influenced by a charged particle flow forming a non-neutral plasma inside these devices. A detailed understanding of the fundamental time-dependent phenomena (e.g., the origin of instabilities) caused by this plasma requires the solution of the Maxwell-Lorentz equations for realistic configurations with a very accurate replica of the border of the domain, where several kinds of boundary conditions are imposed. An attractive method to attack this non-linear equations numerically is the particle-in-cell (PIC) technique. As a preliminary to use the PIC approach, the relevant diode domain has to be covered by an appropriate computational mesh. Therefore, we adopt a grid model based on boundary-fitted coordinates resulting in a quadrilateral mesh zone arrangement with regular data structure. The numerical solution of the Maxwell equations in time domain is obtained by using a finite-volume (FV) approach on a non-rectangular quadrilateral mesh in two space dimensions. A very favorable property of these modern FV schemes consists in the fact that they combine inherent robustness at steep gradients with accurate resolution. In the context of self-consistent charged particle simulation in electromagnetic fields the coupling of a high-resolution FV Maxwell solver with the PIC method is a new way of approximation.
{"title":"KAD12D-a particle-in-cell code based on finite-volume methods","authors":"C. Munz, P. Omnes, R. Schneider, E. Sonnendrucker, E. Stein, U. Voß, T. Westermann","doi":"10.1109/BEAMS.1998.822498","DOIUrl":"https://doi.org/10.1109/BEAMS.1998.822498","url":null,"abstract":"Pulsed-power diodes have been developed at the Forschungszentrum Karlsruhe and are the objects of extensive experimental as well as numerical investigations. The electrical behavior of the diodes is substantially influenced by a charged particle flow forming a non-neutral plasma inside these devices. A detailed understanding of the fundamental time-dependent phenomena (e.g., the origin of instabilities) caused by this plasma requires the solution of the Maxwell-Lorentz equations for realistic configurations with a very accurate replica of the border of the domain, where several kinds of boundary conditions are imposed. An attractive method to attack this non-linear equations numerically is the particle-in-cell (PIC) technique. As a preliminary to use the PIC approach, the relevant diode domain has to be covered by an appropriate computational mesh. Therefore, we adopt a grid model based on boundary-fitted coordinates resulting in a quadrilateral mesh zone arrangement with regular data structure. The numerical solution of the Maxwell equations in time domain is obtained by using a finite-volume (FV) approach on a non-rectangular quadrilateral mesh in two space dimensions. A very favorable property of these modern FV schemes consists in the fact that they combine inherent robustness at steep gradients with accurate resolution. In the context of self-consistent charged particle simulation in electromagnetic fields the coupling of a high-resolution FV Maxwell solver with the PIC method is a new way of approximation.","PeriodicalId":410823,"journal":{"name":"12th International Conference on High-Power Particle Beams. BEAMS'98. Proceedings (Cat. No.98EX103)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129783186","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 : 1998-06-07DOI: 10.1109/BEAMS.1998.822447
Y. Adamyan, V. Vasilevsky, S.N. Kolgatin, G. Shneerson
Experiments on wire explosions in strong longitudinal magnetic fields have shown that the electrical characteristics of conductor explosions are affected by the field. The presence of a longitudinal field with the induction 50-70 T shifts the moment of the explosion and changes the qualitative dependency of voltage vs. time. Previously the possibility of essential heating and acceleration of plasma caused by the generation of azimuthal currents at electrical explosion in longitudinal magnetic field has been shown. Here a one-dimensional analytic plane model illustrating the possibility and explaining the effects of acceleration and conducting media heating under its expansion across the given external field is discussed. Also the description of the experiments is presented in which this effect at the expansion of the low density gas area forming around the wire during its electrical explosion in the vacuum was observed.
{"title":"Forming of high-speed radial plasma flow due to its heating by induced azimuthal current in electrical explosion of wires in extra-high magnetic field","authors":"Y. Adamyan, V. Vasilevsky, S.N. Kolgatin, G. Shneerson","doi":"10.1109/BEAMS.1998.822447","DOIUrl":"https://doi.org/10.1109/BEAMS.1998.822447","url":null,"abstract":"Experiments on wire explosions in strong longitudinal magnetic fields have shown that the electrical characteristics of conductor explosions are affected by the field. The presence of a longitudinal field with the induction 50-70 T shifts the moment of the explosion and changes the qualitative dependency of voltage vs. time. Previously the possibility of essential heating and acceleration of plasma caused by the generation of azimuthal currents at electrical explosion in longitudinal magnetic field has been shown. Here a one-dimensional analytic plane model illustrating the possibility and explaining the effects of acceleration and conducting media heating under its expansion across the given external field is discussed. Also the description of the experiments is presented in which this effect at the expansion of the low density gas area forming around the wire during its electrical explosion in the vacuum was observed.","PeriodicalId":410823,"journal":{"name":"12th International Conference on High-Power Particle Beams. BEAMS'98. Proceedings (Cat. No.98EX103)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127629385","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 : 1998-06-07DOI: 10.1109/BEAMS.1998.817026
Y. Novoselov, G. V. Denisov, A. Suslov
Carbon bisulfide as a toxic impurity is present in large amounts in the gaseous waste produced by a number of industries, specifically in the production of viscose. One of the ways to lower the carbon bisulfide content of waste gases is by treating these with pulsed electron beams. Removing from air exposed to microsecond-duration electron beams is possible with low expenditures of energy, less than the bond breaking energy of this molecule. In the present communication, we furnish results of experimental studies on the removal, by use of pulsed electron beams, of the carbon bisulphide impurity from a gas mixture simulating the composition of actual industrial wastes.
{"title":"Pulsed electron beams for removal of CS/sub 2/ from air","authors":"Y. Novoselov, G. V. Denisov, A. Suslov","doi":"10.1109/BEAMS.1998.817026","DOIUrl":"https://doi.org/10.1109/BEAMS.1998.817026","url":null,"abstract":"Carbon bisulfide as a toxic impurity is present in large amounts in the gaseous waste produced by a number of industries, specifically in the production of viscose. One of the ways to lower the carbon bisulfide content of waste gases is by treating these with pulsed electron beams. Removing from air exposed to microsecond-duration electron beams is possible with low expenditures of energy, less than the bond breaking energy of this molecule. In the present communication, we furnish results of experimental studies on the removal, by use of pulsed electron beams, of the carbon bisulphide impurity from a gas mixture simulating the composition of actual industrial wastes.","PeriodicalId":410823,"journal":{"name":"12th International Conference on High-Power Particle Beams. BEAMS'98. Proceedings (Cat. No.98EX103)","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121821766","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 : 1998-06-07DOI: 10.1109/BEAMS.1998.822445
S. Semushin, A. Chuvatin
The numerical simulations of a plasma opening switch (POS) involve a lot of complex physical problems. Here the two temperature magnetohydrodynamic model (MHD) is used. The computations with such model are not so time consuming, as for the particle codes, and they give reasonable results. The effect of the Hall term in MHD equations is essential for correct physical description of the process. Another essential point is in the physically correct description of plasma-vacuum boundary, where the magnetic field detaches the plasma current carrier and passes to the load. The two stages can be separated in POS dynamics. The first one is conductivity, when plasma ports the current. It is well described by MHD equations. Second stage, the opening, can be described by MHD equation, but with the attentive analysis of applicability of such a model. The simulations were concentrated mainly on the different types of POS behaviour. Such an approach can be used for optimisation of the composite plasma configuration of POS, which had been proposed to be one of the possible ways of improvement of the POS performance.
{"title":"Hall MHD simulation of plasma behaviour in an opening switch","authors":"S. Semushin, A. Chuvatin","doi":"10.1109/BEAMS.1998.822445","DOIUrl":"https://doi.org/10.1109/BEAMS.1998.822445","url":null,"abstract":"The numerical simulations of a plasma opening switch (POS) involve a lot of complex physical problems. Here the two temperature magnetohydrodynamic model (MHD) is used. The computations with such model are not so time consuming, as for the particle codes, and they give reasonable results. The effect of the Hall term in MHD equations is essential for correct physical description of the process. Another essential point is in the physically correct description of plasma-vacuum boundary, where the magnetic field detaches the plasma current carrier and passes to the load. The two stages can be separated in POS dynamics. The first one is conductivity, when plasma ports the current. It is well described by MHD equations. Second stage, the opening, can be described by MHD equation, but with the attentive analysis of applicability of such a model. The simulations were concentrated mainly on the different types of POS behaviour. Such an approach can be used for optimisation of the composite plasma configuration of POS, which had been proposed to be one of the possible ways of improvement of the POS performance.","PeriodicalId":410823,"journal":{"name":"12th International Conference on High-Power Particle Beams. BEAMS'98. Proceedings (Cat. No.98EX103)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121312597","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 : 1998-06-07DOI: 10.1109/BEAMS.1998.822406
K. Takata, Y. H. Chin, H. Mizuno, S. Fukuda, S. Tokumoto, S. Michizono, S. Matsumoto, H. Tsutsui, S. Kazakov
X-band klystrons (XB-72K) designed for the Next Linear Collider (NLC) are described. Klystrons having traveling-wave output structures in order to reduce the electric fields and an RF output power of around 70 MW have been obtained. A new klystron-simulation code using "MAGIC" has been developed at KEK, and the simulation results agree well with the experimental data. The next klystron was designed using the code; an RF output of 120 MW is obtained in the simulation. The klystron is being manufactured and it will be tested this November.
{"title":"X-band klystron development at KEK","authors":"K. Takata, Y. H. Chin, H. Mizuno, S. Fukuda, S. Tokumoto, S. Michizono, S. Matsumoto, H. Tsutsui, S. Kazakov","doi":"10.1109/BEAMS.1998.822406","DOIUrl":"https://doi.org/10.1109/BEAMS.1998.822406","url":null,"abstract":"X-band klystrons (XB-72K) designed for the Next Linear Collider (NLC) are described. Klystrons having traveling-wave output structures in order to reduce the electric fields and an RF output power of around 70 MW have been obtained. A new klystron-simulation code using \"MAGIC\" has been developed at KEK, and the simulation results agree well with the experimental data. The next klystron was designed using the code; an RF output of 120 MW is obtained in the simulation. The klystron is being manufactured and it will be tested this November.","PeriodicalId":410823,"journal":{"name":"12th International Conference on High-Power Particle Beams. BEAMS'98. Proceedings (Cat. No.98EX103)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127792994","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 : 1998-06-07DOI: 10.1109/BEAMS.1998.816997
M.A. Zavjalov, V.I. Perevodchikov, A. Shapiro
The main aspects of the problem of high-power broad-band gas-plasma-filled microwave device designed as a sealed tube, including beam-plasma processes, gas-dynamic system, electron optical system and cathode ion protection, are discussed. A non-relativistic beam-plasma microwave amplifier has been created to operate at output power up to 20 kW, electron efficiency 30% and pass-band width up to 30%.
{"title":"Problems of cathode design and breakdown avoidance relevant to high-power broadband gas-plasma-filled microwave sources","authors":"M.A. Zavjalov, V.I. Perevodchikov, A. Shapiro","doi":"10.1109/BEAMS.1998.816997","DOIUrl":"https://doi.org/10.1109/BEAMS.1998.816997","url":null,"abstract":"The main aspects of the problem of high-power broad-band gas-plasma-filled microwave device designed as a sealed tube, including beam-plasma processes, gas-dynamic system, electron optical system and cathode ion protection, are discussed. A non-relativistic beam-plasma microwave amplifier has been created to operate at output power up to 20 kW, electron efficiency 30% and pass-band width up to 30%.","PeriodicalId":410823,"journal":{"name":"12th International Conference on High-Power Particle Beams. BEAMS'98. Proceedings (Cat. No.98EX103)","volume":"245 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127536151","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 : 1998-06-07DOI: 10.1109/BEAMS.1998.822404
W. Urbanus, W. Bongers, V. Bratman, M. Caplan, G. Denisov, C. van der Geer, P. Manintveld, J. Plomp, J. Pluygers, A. Poelman, A. Savilov, P. Smeets, F. Schuller, A. Varfolomeev, A. Verhoeven
At the FOM Institute for Plasma Physics "Rijnhuizen", The Netherlands, an electrostatic high power free-electron maser is operated at various frequencies. An output power of 730 kW at 206 GHz is generated by a 7.2 A, 1.77 MeV electron beam, and 360 kW at 167 GHz is generated by a 7.0 A, 1.61 MeV electron beam. The lower output power at the latter frequency is due to relatively high losses in the present mm-wave cavity. It is shown experimentally and by simulations that, depending on the electron beam energy, the FEM can operate in single-frequency regime. So far, the pulse length was limited to some 12 /spl mu/S. Nevertheless, many aspects of generation of mm-wave power have been explored, such as the dependency on electron beam current and energy and settings of the mm-wave cavity.
{"title":"The Dutch free-electron maser: 730 kW, 200 GHz","authors":"W. Urbanus, W. Bongers, V. Bratman, M. Caplan, G. Denisov, C. van der Geer, P. Manintveld, J. Plomp, J. Pluygers, A. Poelman, A. Savilov, P. Smeets, F. Schuller, A. Varfolomeev, A. Verhoeven","doi":"10.1109/BEAMS.1998.822404","DOIUrl":"https://doi.org/10.1109/BEAMS.1998.822404","url":null,"abstract":"At the FOM Institute for Plasma Physics \"Rijnhuizen\", The Netherlands, an electrostatic high power free-electron maser is operated at various frequencies. An output power of 730 kW at 206 GHz is generated by a 7.2 A, 1.77 MeV electron beam, and 360 kW at 167 GHz is generated by a 7.0 A, 1.61 MeV electron beam. The lower output power at the latter frequency is due to relatively high losses in the present mm-wave cavity. It is shown experimentally and by simulations that, depending on the electron beam energy, the FEM can operate in single-frequency regime. So far, the pulse length was limited to some 12 /spl mu/S. Nevertheless, many aspects of generation of mm-wave power have been explored, such as the dependency on electron beam current and energy and settings of the mm-wave cavity.","PeriodicalId":410823,"journal":{"name":"12th International Conference on High-Power Particle Beams. BEAMS'98. Proceedings (Cat. No.98EX103)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133759689","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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