Pub Date : 2017-10-01DOI: 10.23919/EUMIC.2017.8230654
K. Ahmeda, B. Ubochi, K. Kalna, B. Benbakhti, S. Duffy, W. Zhang, A. Soltani
The interplay of self-heating and polarization affecting the current is studied in Al0.32Ga0.68N/AlN/GaN/Al0.1Ga0.9N Transmission Line Model (TLM) heterostructures with a scaled source-drain distance. The study is based on meticulously calibrated TCAD simulations against I-V experimental characteristics using an electro-thermal model. The electro-thermal simulations show hot-spots at the edge of the drain contact due to a large electric field affecting the device reliability. Due to the applied electrical stress, the total polarization, relative to the 18 pm heterostructure, decreases by 7 %, 10 % and 17% during a reduction of the source-to-drain distance to the 12 pm, 8 pm, and 4 pm, respectively, as a result of the additional strain induced by electrical stress. This additional stress on source/drain contacts reduces the polarization at the surface as a result of the inverse piezoelectric effect.
{"title":"Self-heating and polarization effects in AlGaN/AlN/GaN/AlGaN based devices","authors":"K. Ahmeda, B. Ubochi, K. Kalna, B. Benbakhti, S. Duffy, W. Zhang, A. Soltani","doi":"10.23919/EUMIC.2017.8230654","DOIUrl":"https://doi.org/10.23919/EUMIC.2017.8230654","url":null,"abstract":"The interplay of self-heating and polarization affecting the current is studied in Al0.32Ga0.68N/AlN/GaN/Al0.1Ga0.9N Transmission Line Model (TLM) heterostructures with a scaled source-drain distance. The study is based on meticulously calibrated TCAD simulations against I-V experimental characteristics using an electro-thermal model. The electro-thermal simulations show hot-spots at the edge of the drain contact due to a large electric field affecting the device reliability. Due to the applied electrical stress, the total polarization, relative to the 18 pm heterostructure, decreases by 7 %, 10 % and 17% during a reduction of the source-to-drain distance to the 12 pm, 8 pm, and 4 pm, respectively, as a result of the additional strain induced by electrical stress. This additional stress on source/drain contacts reduces the polarization at the surface as a result of the inverse piezoelectric effect.","PeriodicalId":120932,"journal":{"name":"2017 12th European Microwave Integrated Circuits Conference (EuMIC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128912814","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 : 2017-10-01DOI: 10.23919/EUMIC.2017.8230670
Chun-Yu Fan, M. Wei, R. Negra
This paper presents a new simplified 4-port deembedding method using one thru dummy structure. In the proposed method, the probe pads and feeding lines, are acquired and decomposed from measurement of a thru dummy. The method does not rely on an equivalent-circuit model. Thus good accuracy can be obtained due to no parameter extraction for a model. Besides, the feeding structure has fewer geometrical restriction compared to other 4-port de-embedding methods. Three test keys, which have different feeding structures, are fabricated to demonstrate the method. Experiments confirm that the proposed method is able to perform de-embedding properly. In addition, the thru dummy needed in the proposed de-embedding method consumes small area.
{"title":"Simplified thru-only 4-port de-embedding method","authors":"Chun-Yu Fan, M. Wei, R. Negra","doi":"10.23919/EUMIC.2017.8230670","DOIUrl":"https://doi.org/10.23919/EUMIC.2017.8230670","url":null,"abstract":"This paper presents a new simplified 4-port deembedding method using one thru dummy structure. In the proposed method, the probe pads and feeding lines, are acquired and decomposed from measurement of a thru dummy. The method does not rely on an equivalent-circuit model. Thus good accuracy can be obtained due to no parameter extraction for a model. Besides, the feeding structure has fewer geometrical restriction compared to other 4-port de-embedding methods. Three test keys, which have different feeding structures, are fabricated to demonstrate the method. Experiments confirm that the proposed method is able to perform de-embedding properly. In addition, the thru dummy needed in the proposed de-embedding method consumes small area.","PeriodicalId":120932,"journal":{"name":"2017 12th European Microwave Integrated Circuits Conference (EuMIC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130597204","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 : 2017-10-01DOI: 10.23919/EUMIC.2017.8230688
Chen-Wei Wu, Tzu-Yuan Huang, Yuan-Hung Hsiao, Yi-Ching Wu, Huei Wang
This paper presents a signal-reused technique for distributed amplifier (DA) by using feedback transformers between the cascaded gain stages. With a proper coupling coefficient (k) of the feedback transformer, the gain-bandwidth (GBW) product of DA can be improved by extending the bandwidth of DA while maintaining the same average gain without increasing the power consumption. The DA is realized by 0.18-pm CMOS technology and it achieves an average small-signal gain of 12-dB and a small-signal bandwidth of 33.5 GHz with total dc power of 69 mW. The chip size is 0.72 mm2 including the pads.
{"title":"A compact and low DC power distributed amplifier with cascaded gain stages using signal-reused technique in 0.18-pm CMOS","authors":"Chen-Wei Wu, Tzu-Yuan Huang, Yuan-Hung Hsiao, Yi-Ching Wu, Huei Wang","doi":"10.23919/EUMIC.2017.8230688","DOIUrl":"https://doi.org/10.23919/EUMIC.2017.8230688","url":null,"abstract":"This paper presents a signal-reused technique for distributed amplifier (DA) by using feedback transformers between the cascaded gain stages. With a proper coupling coefficient (k) of the feedback transformer, the gain-bandwidth (GBW) product of DA can be improved by extending the bandwidth of DA while maintaining the same average gain without increasing the power consumption. The DA is realized by 0.18-pm CMOS technology and it achieves an average small-signal gain of 12-dB and a small-signal bandwidth of 33.5 GHz with total dc power of 69 mW. The chip size is 0.72 mm2 including the pads.","PeriodicalId":120932,"journal":{"name":"2017 12th European Microwave Integrated Circuits Conference (EuMIC)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126252527","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 : 2017-10-01DOI: 10.23919/EUMIC.2017.8230709
P. R. Vazquez, J. Grzyb, N. Sarmah, B. Heinemann, U. Pfeiffer
This paper presents a fully-integrated direct-conversion fundamentally-operated mixer-first quadrature receiver chip working at 240 GHz. It has been implemented in a 0.13-μm SiGe HBT technology with fT/fmax of 350/550 GHz. The chip includes an LO path based on a x16 multiplier with a 3-stage PA, driven externally from the PCB at 14–18 GHz. The LO signal is split in quadrature by a broadband coupler. It drives two double-balanced fundamentally-operated mixers with their RF ports connected directly to a wideband lens-integrated linearly-polarized on-chip ring antenna. For low-cost packaging, the chip-on-lens assembly is wire-bonded onto a high-speed PCB, where an on-board 8-section step-impedance microstrip-line low-pass filter has been implemented to compensate the wire-bond inductance at the IF outputs. The 3-dB RF/LO operation BW (with fixed IF) is 47 GHz with peak CG of 7.8 dB, and minimum SSB NF of 11.3 dB, whereas a 3-dB IF bandwidth is at least 12 GHz. All measurement results have been taken at the board-level and include the implementation losses of both the antenna and the on-board high-speed interconnects. The receiver IQ amplitude imbalance is below 1.58 dB for the 210–280 GHz band. In combination with a 9-mm silicon lens, the receiver module provides a directivity of 25.2 to 27.04 dBi from 210 to 280 GHz.
{"title":"A 219–266 GHz fully-integrated direct-conversion IQ receiver module in a SiGe HBT technology","authors":"P. R. Vazquez, J. Grzyb, N. Sarmah, B. Heinemann, U. Pfeiffer","doi":"10.23919/EUMIC.2017.8230709","DOIUrl":"https://doi.org/10.23919/EUMIC.2017.8230709","url":null,"abstract":"This paper presents a fully-integrated direct-conversion fundamentally-operated mixer-first quadrature receiver chip working at 240 GHz. It has been implemented in a 0.13-μm SiGe HBT technology with fT/fmax of 350/550 GHz. The chip includes an LO path based on a x16 multiplier with a 3-stage PA, driven externally from the PCB at 14–18 GHz. The LO signal is split in quadrature by a broadband coupler. It drives two double-balanced fundamentally-operated mixers with their RF ports connected directly to a wideband lens-integrated linearly-polarized on-chip ring antenna. For low-cost packaging, the chip-on-lens assembly is wire-bonded onto a high-speed PCB, where an on-board 8-section step-impedance microstrip-line low-pass filter has been implemented to compensate the wire-bond inductance at the IF outputs. The 3-dB RF/LO operation BW (with fixed IF) is 47 GHz with peak CG of 7.8 dB, and minimum SSB NF of 11.3 dB, whereas a 3-dB IF bandwidth is at least 12 GHz. All measurement results have been taken at the board-level and include the implementation losses of both the antenna and the on-board high-speed interconnects. The receiver IQ amplitude imbalance is below 1.58 dB for the 210–280 GHz band. In combination with a 9-mm silicon lens, the receiver module provides a directivity of 25.2 to 27.04 dBi from 210 to 280 GHz.","PeriodicalId":120932,"journal":{"name":"2017 12th European Microwave Integrated Circuits Conference (EuMIC)","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126828670","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 : 1900-01-01DOI: 10.23919/eumc.2017.8231051
E. D. de Oliveira, L. P. Pontes, Crislane P. N. da Silva, M. T. de Melo, B. D. de Oliveira, I. Llamas-Garro
This paper presents the design and simulated results of a Phase Shifter where the delay lines have been designed using the Hilbert's Fractal Line. Simulated results for fractal lines' group delay and PIN diode switch are also presented. Using the fractal lines allowed for a much more compact design when compared to traditional delay lines. Phase shift simulated results are in good accordance with theory.
{"title":"Microstrip fractal-based phase shifter: An UHF phase shifter based on with Hilbert's fractal delay lines","authors":"E. D. de Oliveira, L. P. Pontes, Crislane P. N. da Silva, M. T. de Melo, B. D. de Oliveira, I. Llamas-Garro","doi":"10.23919/eumc.2017.8231051","DOIUrl":"https://doi.org/10.23919/eumc.2017.8231051","url":null,"abstract":"This paper presents the design and simulated results of a Phase Shifter where the delay lines have been designed using the Hilbert's Fractal Line. Simulated results for fractal lines' group delay and PIN diode switch are also presented. Using the fractal lines allowed for a much more compact design when compared to traditional delay lines. Phase shift simulated results are in good accordance with theory.","PeriodicalId":120932,"journal":{"name":"2017 12th European Microwave Integrated Circuits Conference (EuMIC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130777174","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 : 1900-01-01DOI: 10.23919/eumc.2017.8231029
P. Pursula, A. Lamminen, M. Kantanen, J. Saarilahti, V. Ermolov
We demonstrate first results towards sub-THz integration system based on micromachined waveguides on Silicon. The demonstrated components at 270 GHz include waveguides, filters and vias, as well as a loss-low transition between the waveguide and the MMIC. The developed process relies on well known MEMS manufacturing methods and Silicon wafer substrates, promising scalable and cost efficient system integration method for future communication and sensing applications.
{"title":"Sub-THz micromachined waveguides for wafer level integration of MMICs","authors":"P. Pursula, A. Lamminen, M. Kantanen, J. Saarilahti, V. Ermolov","doi":"10.23919/eumc.2017.8231029","DOIUrl":"https://doi.org/10.23919/eumc.2017.8231029","url":null,"abstract":"We demonstrate first results towards sub-THz integration system based on micromachined waveguides on Silicon. The demonstrated components at 270 GHz include waveguides, filters and vias, as well as a loss-low transition between the waveguide and the MMIC. The developed process relies on well known MEMS manufacturing methods and Silicon wafer substrates, promising scalable and cost efficient system integration method for future communication and sensing applications.","PeriodicalId":120932,"journal":{"name":"2017 12th European Microwave Integrated Circuits Conference (EuMIC)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125542513","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 : 1900-01-01DOI: 10.23919/eumc.2017.8231045
C. Crespo-Cadenas, J. Reina-Tosina, M. J. Madero-Ayora, J. A. Becerra-González
The main contribution of this paper is the derivation of theoretical relationships between the impairments in an I/Q modulator and their impact on the structure of the kernels of a Volterra behavioral model. The analysis is focused on the imperfections produced by I/Q gain imbalance and quadrature error and shows how the model coefficients depend on the impairment strength. Closed-form expressions are experimentally validated with a commercial I/Q modulator for which artificially-added impairments were swept and modeled through a general complexvalued Volterra model. The excellent correspondence between measurements and analysis can help to the joint modeling of a modulator and a power amplifier connected in cascade.
{"title":"Relationship between a pruned volterra model structure and impairments in an I/Q modulator","authors":"C. Crespo-Cadenas, J. Reina-Tosina, M. J. Madero-Ayora, J. A. Becerra-González","doi":"10.23919/eumc.2017.8231045","DOIUrl":"https://doi.org/10.23919/eumc.2017.8231045","url":null,"abstract":"The main contribution of this paper is the derivation of theoretical relationships between the impairments in an I/Q modulator and their impact on the structure of the kernels of a Volterra behavioral model. The analysis is focused on the imperfections produced by I/Q gain imbalance and quadrature error and shows how the model coefficients depend on the impairment strength. Closed-form expressions are experimentally validated with a commercial I/Q modulator for which artificially-added impairments were swept and modeled through a general complexvalued Volterra model. The excellent correspondence between measurements and analysis can help to the joint modeling of a modulator and a power amplifier connected in cascade.","PeriodicalId":120932,"journal":{"name":"2017 12th European Microwave Integrated Circuits Conference (EuMIC)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115195526","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 : 1900-01-01DOI: 10.23919/eumc.2017.8231028
Zhijian Yu, Wei Wang
In the paper, experimental results of a novel dualband DPD model based on CPWL functions [4] are provided. With the feature of CPWL functions that is a minimal formulation requiring minimal amount of memory to store the parameters, the CPWL-based DPD model can release the requirement for huge number of coefficients for concurrent dual-band DPD systems. Our test results show the CPWL-based DPD model achieves similar performance as the GMP model ever it only has 15% of number of coefficients of the GMP model.
{"title":"Concurrent dual-band digital predistortion based on canonical piecewise linear functions","authors":"Zhijian Yu, Wei Wang","doi":"10.23919/eumc.2017.8231028","DOIUrl":"https://doi.org/10.23919/eumc.2017.8231028","url":null,"abstract":"In the paper, experimental results of a novel dualband DPD model based on CPWL functions [4] are provided. With the feature of CPWL functions that is a minimal formulation requiring minimal amount of memory to store the parameters, the CPWL-based DPD model can release the requirement for huge number of coefficients for concurrent dual-band DPD systems. Our test results show the CPWL-based DPD model achieves similar performance as the GMP model ever it only has 15% of number of coefficients of the GMP model.","PeriodicalId":120932,"journal":{"name":"2017 12th European Microwave Integrated Circuits Conference (EuMIC)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124596246","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 : 1900-01-01DOI: 10.23919/eumc.2017.8231035
A. Prasetiadi, M. Jost, B. Schulz, M. Quibeldey, T. Rabe, R. Follmann, R. Jakoby
A 30 GHz liquid-crystal-based amplitude tuner is proposed for the first time. The amplitude of a signal can be controlled by using the interference principle. An input signal is divided into a tunable liquid crystal phase shifter and a fixed transmission line. Later, the divided signals are combined together at the output port. The output amplitude depends on the phase difference between the tunable and the fixed line. The low temperature co-fired ceramic technology is utilized to fabricate the device. The measurement shows an attenuation range of 11 dB to 30 dB with a maximum biasing voltage of 100 V.
{"title":"Liquid-crystal-based amplitude tuner fabricated in LTCC technology","authors":"A. Prasetiadi, M. Jost, B. Schulz, M. Quibeldey, T. Rabe, R. Follmann, R. Jakoby","doi":"10.23919/eumc.2017.8231035","DOIUrl":"https://doi.org/10.23919/eumc.2017.8231035","url":null,"abstract":"A 30 GHz liquid-crystal-based amplitude tuner is proposed for the first time. The amplitude of a signal can be controlled by using the interference principle. An input signal is divided into a tunable liquid crystal phase shifter and a fixed transmission line. Later, the divided signals are combined together at the output port. The output amplitude depends on the phase difference between the tunable and the fixed line. The low temperature co-fired ceramic technology is utilized to fabricate the device. The measurement shows an attenuation range of 11 dB to 30 dB with a maximum biasing voltage of 100 V.","PeriodicalId":120932,"journal":{"name":"2017 12th European Microwave Integrated Circuits Conference (EuMIC)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126362727","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 : 1900-01-01DOI: 10.23919/eumc.2017.8231037
R. Reese, E. Polat, M. Jost, M. Nickel, R. Jakoby, H. Maune
This work presents a simple approach for a continuously tunable phase shifter design based on liquid crystal (LC) technology for the V-band. The main component of the phase shifter is a partially dielectric filled parallel-plate waveguide. For continuous tunability, liquid crystal is inserted inside the dielectric slab. This assembly, being fed by WR15 waveguides, maintains a simple and efficient way to realize the necessary electric biasing in comparison to hollow waveguide based LC phase shifter. A novel stepped impedance design, which is fabricated on an Ultralam 3850HT substrate is presented. The electrode design is based on Babinet's principle to obtain a homogeneous distribution of the biasing field. Using a voltage of ±150 V, a maximum differential phase shift of 380°, accompanied with an insertion loss between 2.4 to 3.6 dB could be achieved, yielding a high figure of merit of around 113 °/dB at 68 GHz.
{"title":"Liquid crystal based phase shifter in a parallel-plate dielectric waveguide topology at V-band","authors":"R. Reese, E. Polat, M. Jost, M. Nickel, R. Jakoby, H. Maune","doi":"10.23919/eumc.2017.8231037","DOIUrl":"https://doi.org/10.23919/eumc.2017.8231037","url":null,"abstract":"This work presents a simple approach for a continuously tunable phase shifter design based on liquid crystal (LC) technology for the V-band. The main component of the phase shifter is a partially dielectric filled parallel-plate waveguide. For continuous tunability, liquid crystal is inserted inside the dielectric slab. This assembly, being fed by WR15 waveguides, maintains a simple and efficient way to realize the necessary electric biasing in comparison to hollow waveguide based LC phase shifter. A novel stepped impedance design, which is fabricated on an Ultralam 3850HT substrate is presented. The electrode design is based on Babinet's principle to obtain a homogeneous distribution of the biasing field. Using a voltage of ±150 V, a maximum differential phase shift of 380°, accompanied with an insertion loss between 2.4 to 3.6 dB could be achieved, yielding a high figure of merit of around 113 °/dB at 68 GHz.","PeriodicalId":120932,"journal":{"name":"2017 12th European Microwave Integrated Circuits Conference (EuMIC)","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124725647","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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