Pub Date : 2020-08-01DOI: 10.1109/IMS30576.2020.9223773
Xenofon Konstantinou, Cristian J. Herrera-Rodriquez, A. Hardy, J. Albrecht, T. Grotjohn, J. Papapolymerou
This work focuses on the unique high-frequency power-handling capabilities of diamond Schottky Barrier Diodes (SBDs). We demonstrate the design, fabrication, and large-signal RF characterization, via active Load/Source-Pull (L/S-P), of a SBD on single-crystalline diamond (SCD). This is the first time a fully-integrated RF SBD has been fabricated and characterized via high-power impedance matching. The SBD was developed on a p−/p+ boron-doped SCD wafer. Active L/S-P was performed at 10 GHz for an input power (Pin) of 34 dBm, attaining an output power (Pout) of 33.3 dBm, yielding a loss of 0.7 dB under matching conditions and an RF power density of ~ 375 W/mm2. These RF power levels are higher than those available in the literature for SBDs and show that diode large-signal characterization via active L-P can potentially play a significant role in the design of multipliers, rectifiers, and detectors that aim to deliver high $mathrm{P}_{mathrm{out}}$ without thermal degradation.
{"title":"High-Power RF Characterization of Diamond Schottky Barrier Diodes at X-band","authors":"Xenofon Konstantinou, Cristian J. Herrera-Rodriquez, A. Hardy, J. Albrecht, T. Grotjohn, J. Papapolymerou","doi":"10.1109/IMS30576.2020.9223773","DOIUrl":"https://doi.org/10.1109/IMS30576.2020.9223773","url":null,"abstract":"This work focuses on the unique high-frequency power-handling capabilities of diamond Schottky Barrier Diodes (SBDs). We demonstrate the design, fabrication, and large-signal RF characterization, via active Load/Source-Pull (L/S-P), of a SBD on single-crystalline diamond (SCD). This is the first time a fully-integrated RF SBD has been fabricated and characterized via high-power impedance matching. The SBD was developed on a p−/p+ boron-doped SCD wafer. Active L/S-P was performed at 10 GHz for an input power (Pin) of 34 dBm, attaining an output power (Pout) of 33.3 dBm, yielding a loss of 0.7 dB under matching conditions and an RF power density of ~ 375 W/mm2. These RF power levels are higher than those available in the literature for SBDs and show that diode large-signal characterization via active L-P can potentially play a significant role in the design of multipliers, rectifiers, and detectors that aim to deliver high $mathrm{P}_{mathrm{out}}$ without thermal degradation.","PeriodicalId":6784,"journal":{"name":"2020 IEEE/MTT-S International Microwave Symposium (IMS)","volume":"100 1","pages":"297-300"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81391357","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 : 2020-08-01DOI: 10.1109/IMS30576.2020.9224111
T. Tseng, C. Tseng
In this paper, a compact 24-GHz continuous-wave radar sensor is developed to detect the wrist pulse waveform for blood pressure (BP) estimation. The systolic and diastolic BPs can be calculated by the reflective pulse transit time (R-PTT) using the BP computation algorithm. Instead of using conventional PTT, the R-PTT is re-defined as the propagation time interval between the forward and reflected pressure waves observed at the radial artery area in this paper. It can be then extracted from the wrist pulse waveform, which is remotely measured by the radar sensor. The BPs of a 23-year-old female have been continuously monitored for 8 days and compared with the commercial cuff-based BP monitor. The measured mean difference (MD) and standard deviation (SD) of the proposed BP radar sensor are O.55±5.45 mmHg (MD±SD) and -2.26±3.93 mmHg (MD±SD) for systolic and diastolic BPs, respectively.
{"title":"Noncontact Wrist Pulse Waveform Detection Using 24-GHz Continuous-Wave Radar Sensor for Blood Pressure Estimation","authors":"T. Tseng, C. Tseng","doi":"10.1109/IMS30576.2020.9224111","DOIUrl":"https://doi.org/10.1109/IMS30576.2020.9224111","url":null,"abstract":"In this paper, a compact 24-GHz continuous-wave radar sensor is developed to detect the wrist pulse waveform for blood pressure (BP) estimation. The systolic and diastolic BPs can be calculated by the reflective pulse transit time (R-PTT) using the BP computation algorithm. Instead of using conventional PTT, the R-PTT is re-defined as the propagation time interval between the forward and reflected pressure waves observed at the radial artery area in this paper. It can be then extracted from the wrist pulse waveform, which is remotely measured by the radar sensor. The BPs of a 23-year-old female have been continuously monitored for 8 days and compared with the commercial cuff-based BP monitor. The measured mean difference (MD) and standard deviation (SD) of the proposed BP radar sensor are O.55±5.45 mmHg (MD±SD) and -2.26±3.93 mmHg (MD±SD) for systolic and diastolic BPs, respectively.","PeriodicalId":6784,"journal":{"name":"2020 IEEE/MTT-S International Microwave Symposium (IMS)","volume":"39 1","pages":"647-650"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82492300","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 : 2020-08-01DOI: 10.1109/IMS30576.2020.9224020
Stefanos Bakirtzis, Xingqi Zhang, C. Sarris
With 5G communication systems along with several radar and imaging technologies employing millimeter waves, accurately modeling wave propagation at these frequencies is as important as ever. At these frequencies, surface roughness of waveguide components (a side effect of both standard fabrication and 3-D printing) has a pronounced role. Yet, in FDTD, this effect is still modeled through the time-consuming Monte-Carlo method. This paper presents a new approach with distinct advantages over the state of the art. Reflection and transmission through rough slabs is modeled with FDTD and an efficient polynomial chaos expansion of the statistical fields in and around the rough surface. We demonstrate the computational efficiency and accuracy of this technique, which can model both the usual excess attenuation due to small-scale roughness and diffuse scattering effects.
{"title":"Efficient Modeling of Wave Propagation Through Rough Slabs with FDTD","authors":"Stefanos Bakirtzis, Xingqi Zhang, C. Sarris","doi":"10.1109/IMS30576.2020.9224020","DOIUrl":"https://doi.org/10.1109/IMS30576.2020.9224020","url":null,"abstract":"With 5G communication systems along with several radar and imaging technologies employing millimeter waves, accurately modeling wave propagation at these frequencies is as important as ever. At these frequencies, surface roughness of waveguide components (a side effect of both standard fabrication and 3-D printing) has a pronounced role. Yet, in FDTD, this effect is still modeled through the time-consuming Monte-Carlo method. This paper presents a new approach with distinct advantages over the state of the art. Reflection and transmission through rough slabs is modeled with FDTD and an efficient polynomial chaos expansion of the statistical fields in and around the rough surface. We demonstrate the computational efficiency and accuracy of this technique, which can model both the usual excess attenuation due to small-scale roughness and diffuse scattering effects.","PeriodicalId":6784,"journal":{"name":"2020 IEEE/MTT-S International Microwave Symposium (IMS)","volume":"56 1","pages":"864-867"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78639116","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 : 2020-08-01DOI: 10.1109/IMS30576.2020.9223777
Peizhao Li, H. Ren, Y. Gu, B. Pejcinovic, B. Arigong
In this paper, a novel microstrip line symmetric ports 180° coupler is presented to feature arbitrary coupling ratio, transparent termination impedance and second harmonic frequency separation. The proposed coupler is composed of two quadrature hybrid couplers and two phase shifters. The analytical design equations are derived to determine the electrical length of two delay lines which control the coupling ratio and absolute phase delay of proposed coupler. To verify our design concept, six different types of couplers with 1/2 and 1/3 coupling ratio and termination impedance of 25 Ω, 50 Ω and 100 Ω are designed, fabricated and measured. Both simulation and measurement results are in good agreement to further demonstrated proposed design theory.
{"title":"A Second Harmonic Separation Symmetric Ports 180° Coupler with Arbitrary Coupling Ratio and Transparent Terminations","authors":"Peizhao Li, H. Ren, Y. Gu, B. Pejcinovic, B. Arigong","doi":"10.1109/IMS30576.2020.9223777","DOIUrl":"https://doi.org/10.1109/IMS30576.2020.9223777","url":null,"abstract":"In this paper, a novel microstrip line symmetric ports 180° coupler is presented to feature arbitrary coupling ratio, transparent termination impedance and second harmonic frequency separation. The proposed coupler is composed of two quadrature hybrid couplers and two phase shifters. The analytical design equations are derived to determine the electrical length of two delay lines which control the coupling ratio and absolute phase delay of proposed coupler. To verify our design concept, six different types of couplers with 1/2 and 1/3 coupling ratio and termination impedance of 25 Ω, 50 Ω and 100 Ω are designed, fabricated and measured. Both simulation and measurement results are in good agreement to further demonstrated proposed design theory.","PeriodicalId":6784,"journal":{"name":"2020 IEEE/MTT-S International Microwave Symposium (IMS)","volume":"11 1","pages":"908-911"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89259233","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 : 2020-08-01DOI: 10.1109/IMS30576.2020.9224085
E. Guerrero, Patricia Silveira, Ángel Triano, J. Verdú, P. de Paco
This paper explores how acoustic wave (AW) filters whose first resonator is in shunt configuration require particular phase conditions to ensure network feasibility. The position of the transmission zeros (TZs) might lead to non-feasible solutions with negative values of the static capacitance Co of the first and last resonators and, therefore, the role of the first TZ in this behaviour is investigated. A lowpass synthesis view of these issues is presented providing different approaches for designers to achieve feasible networks.
{"title":"Synthesis Considerations for Shunt-Starting Acoustic Wave Ladder Filters and Duplexers","authors":"E. Guerrero, Patricia Silveira, Ángel Triano, J. Verdú, P. de Paco","doi":"10.1109/IMS30576.2020.9224085","DOIUrl":"https://doi.org/10.1109/IMS30576.2020.9224085","url":null,"abstract":"This paper explores how acoustic wave (AW) filters whose first resonator is in shunt configuration require particular phase conditions to ensure network feasibility. The position of the transmission zeros (TZs) might lead to non-feasible solutions with negative values of the static capacitance Co of the first and last resonators and, therefore, the role of the first TZ in this behaviour is investigated. A lowpass synthesis view of these issues is presented providing different approaches for designers to achieve feasible networks.","PeriodicalId":6784,"journal":{"name":"2020 IEEE/MTT-S International Microwave Symposium (IMS)","volume":"17 1","pages":"920-923"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87796030","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 : 2020-08-01DOI: 10.1109/IMS30576.2020.9223892
J. Rautio, Matthew Thelen
Method of moments analysis of planar multi-layer circuits typically assumes conductors are infinitely thin and only surface currents need be modeled. Modern fabrication methods, especially for high frequency integrated circuits, can easily create structures that require modeling volume current. Combined with previous work, this paper presents, for the first time, a complete volume current based method of moments analysis of shielded multi-layer circuits. The new volume and the original surface subsections are all evaluated to full numerical precision by 2-D FFT and have little impact on analysis speed.
{"title":"A Volume Current Based Method of Moments Analysis of Shielded Planar 3-D Circuits in Layered Media","authors":"J. Rautio, Matthew Thelen","doi":"10.1109/IMS30576.2020.9223892","DOIUrl":"https://doi.org/10.1109/IMS30576.2020.9223892","url":null,"abstract":"Method of moments analysis of planar multi-layer circuits typically assumes conductors are infinitely thin and only surface currents need be modeled. Modern fabrication methods, especially for high frequency integrated circuits, can easily create structures that require modeling volume current. Combined with previous work, this paper presents, for the first time, a complete volume current based method of moments analysis of shielded multi-layer circuits. The new volume and the original surface subsections are all evaluated to full numerical precision by 2-D FFT and have little impact on analysis speed.","PeriodicalId":6784,"journal":{"name":"2020 IEEE/MTT-S International Microwave Symposium (IMS)","volume":"1978 1","pages":"146-149"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87796730","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 : 2020-08-01DOI: 10.1109/IMS30576.2020.9223955
Jordan Corsi, G. Rehder, L. Gomes, M. Bertrand, A. Serrano, E. Pistono, P. Ferrari
In this paper, the slow-wave effect and air-filled technology are combined to achieve a compact and efficient substrate integrated waveguide in the W-band. The MnM interposer technology, based on a nanoporous alumina membrane and copper nanowires, allowing a simple through substrate via fabrication, was used. A first partially-air-filled slow-wave substrate integrated waveguide was fabricated and measured, resulting in a reduction of the attenuation constant by 75% at 1.2 times the cut-off frequency as compared to the classic SIW, with Slimilar dimensions.
{"title":"Partially-Air-Filled Slow-Wave Substrate Integrated Waveguide in Metallic Nanowire Membrane Technology","authors":"Jordan Corsi, G. Rehder, L. Gomes, M. Bertrand, A. Serrano, E. Pistono, P. Ferrari","doi":"10.1109/IMS30576.2020.9223955","DOIUrl":"https://doi.org/10.1109/IMS30576.2020.9223955","url":null,"abstract":"In this paper, the slow-wave effect and air-filled technology are combined to achieve a compact and efficient substrate integrated waveguide in the W-band. The MnM interposer technology, based on a nanoporous alumina membrane and copper nanowires, allowing a simple through substrate via fabrication, was used. A first partially-air-filled slow-wave substrate integrated waveguide was fabricated and measured, resulting in a reduction of the attenuation constant by 75% at 1.2 times the cut-off frequency as compared to the classic SIW, with Slimilar dimensions.","PeriodicalId":6784,"journal":{"name":"2020 IEEE/MTT-S International Microwave Symposium (IMS)","volume":"111 3S 1","pages":"9-12"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88072789","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 : 2020-08-01DOI: 10.1109/IMS30576.2020.9224061
Shireen Warnock, Chang-Lee Chen, Jeffrey Knechtl, R. Molnar, D. Yost, M. Cook, C. Stull, Ryan Johnson, C. Galbraith, J. Daulton, Weilin Hu, G. Pinelli, J. Perozek, T. Palacios, Beijia Zhang, J. Herd, C. Keast
In this paper we present a fully CMOS-compatible fabrication process for GaN-on-Si monolithic microwave integrated circuits (MMICs) on 200-mm-diameter wafers. This process also enables wafer-level 3D integration of GaN MMICs with Si CMOS circuits to enhance performance and functionality while reducing the size, weight, power, as well as the cost. We demonstrate our progress towards full 3D integration, including a discussion on GaN HEMT fabrication and bonding with a Si CMOS wafer. With the use of an InA1N barrier layer we show a GaN-on-Si HEMT output power of 4.5 W/mm and PAE of 53% at 10 GHz.
{"title":"InAlN/GaN-on-Si HEMT with 4.5 W/mm in a 200-mm CMOS-Compatible MMIC Process for 3D Integration","authors":"Shireen Warnock, Chang-Lee Chen, Jeffrey Knechtl, R. Molnar, D. Yost, M. Cook, C. Stull, Ryan Johnson, C. Galbraith, J. Daulton, Weilin Hu, G. Pinelli, J. Perozek, T. Palacios, Beijia Zhang, J. Herd, C. Keast","doi":"10.1109/IMS30576.2020.9224061","DOIUrl":"https://doi.org/10.1109/IMS30576.2020.9224061","url":null,"abstract":"In this paper we present a fully CMOS-compatible fabrication process for GaN-on-Si monolithic microwave integrated circuits (MMICs) on 200-mm-diameter wafers. This process also enables wafer-level 3D integration of GaN MMICs with Si CMOS circuits to enhance performance and functionality while reducing the size, weight, power, as well as the cost. We demonstrate our progress towards full 3D integration, including a discussion on GaN HEMT fabrication and bonding with a Si CMOS wafer. With the use of an InA1N barrier layer we show a GaN-on-Si HEMT output power of 4.5 W/mm and PAE of 53% at 10 GHz.","PeriodicalId":6784,"journal":{"name":"2020 IEEE/MTT-S International Microwave Symposium (IMS)","volume":"128 1","pages":"289-292"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87965357","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 : 2020-08-01DOI: 10.1109/IMS30576.2020.9223972
H. Jia, R. Mansour
In this paper, we use a unique behavior of spiral inductors designed intentionally to have a large parasitic capacitance in the realization of a tunable band reject filter. It is shown that, regardless of the operating frequency, the conductivity of the metal strips forming the inductor has a significant impact on how the spiral inductor behaves as an inductor or a capacitor. The concept is used to demonstrate a band reject filter made out of niobium operating at 4K, whose conductivity can be changed with the application of a dc current. The same concept can be employed using other materials with conductivity that can be controlled either electrically, thermally or optically.
{"title":"Behavior of lossy Spiral Inductors and Their Applications to the Design of Tunable Band Reject Filters","authors":"H. Jia, R. Mansour","doi":"10.1109/IMS30576.2020.9223972","DOIUrl":"https://doi.org/10.1109/IMS30576.2020.9223972","url":null,"abstract":"In this paper, we use a unique behavior of spiral inductors designed intentionally to have a large parasitic capacitance in the realization of a tunable band reject filter. It is shown that, regardless of the operating frequency, the conductivity of the metal strips forming the inductor has a significant impact on how the spiral inductor behaves as an inductor or a capacitor. The concept is used to demonstrate a band reject filter made out of niobium operating at 4K, whose conductivity can be changed with the application of a dc current. The same concept can be employed using other materials with conductivity that can be controlled either electrically, thermally or optically.","PeriodicalId":6784,"journal":{"name":"2020 IEEE/MTT-S International Microwave Symposium (IMS)","volume":"39 1","pages":"815-817"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86819311","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 : 2020-08-01DOI: 10.1109/IMS30576.2020.9223914
M. Abdolrazzaghi, Nazli Kazemi, M. Daneshmand
Microfluidic sensing is conventionally conducted using passive substrate integrated waveguides (SIW) due to high-Q performance. The proposed sensor, in this work, converts the very resonator (Qu ~ 600) at 3.17 GHz into oscillatory sensor utilizing negative feedback resistance. The phase noise is measured -143.4 dBc/Hz @ 1MHz with figure of merit of -203 dBc/Hz @ 1MHz. This active cavity with an embedded microfluidic channel has preserved the sensitivity compared with passive cavity and performs stably in sensing ultra-high salinity of 25% - 150 % in salt-in-water solutions.
{"title":"An SIW Oscillator for Microfluidic Lossy Medium Characterization","authors":"M. Abdolrazzaghi, Nazli Kazemi, M. Daneshmand","doi":"10.1109/IMS30576.2020.9223914","DOIUrl":"https://doi.org/10.1109/IMS30576.2020.9223914","url":null,"abstract":"Microfluidic sensing is conventionally conducted using passive substrate integrated waveguides (SIW) due to high-Q performance. The proposed sensor, in this work, converts the very resonator (Qu ~ 600) at 3.17 GHz into oscillatory sensor utilizing negative feedback resistance. The phase noise is measured -143.4 dBc/Hz @ 1MHz with figure of merit of -203 dBc/Hz @ 1MHz. This active cavity with an embedded microfluidic channel has preserved the sensitivity compared with passive cavity and performs stably in sensing ultra-high salinity of 25% - 150 % in salt-in-water solutions.","PeriodicalId":6784,"journal":{"name":"2020 IEEE/MTT-S International Microwave Symposium (IMS)","volume":"43 1","pages":"221-224"},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86868561","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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