Pub Date : 2016-12-01DOI: 10.1109/IMARC.2016.7939620
Kinjal Parmar, Shailendra Singh
This paper reports the design of 50–60 GHz probe type waveguide to microstrip transition on LTCC substrate, which acts as an initial development towards integrated MMIC hermetic packaging in millimeter-wave systems. The transition shows a simulated return loss better than 15 dB and insertion loss less than 0.4 dB in back to back configuration. The measured insertion loss is 1.2 to 1.8 dB with return loss bettering 12 dB in the range of 50–60 GHz.
{"title":"50–60 GHz waveguide to microstrip transition on LTCC for enabling integrated MMIC packaging","authors":"Kinjal Parmar, Shailendra Singh","doi":"10.1109/IMARC.2016.7939620","DOIUrl":"https://doi.org/10.1109/IMARC.2016.7939620","url":null,"abstract":"This paper reports the design of 50–60 GHz probe type waveguide to microstrip transition on LTCC substrate, which acts as an initial development towards integrated MMIC hermetic packaging in millimeter-wave systems. The transition shows a simulated return loss better than 15 dB and insertion loss less than 0.4 dB in back to back configuration. The measured insertion loss is 1.2 to 1.8 dB with return loss bettering 12 dB in the range of 50–60 GHz.","PeriodicalId":341661,"journal":{"name":"2016 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125377617","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 : 2016-12-01DOI: 10.1109/IMARC.2016.7939623
Sohni Jain, Vuk Vojisaveljevic, E. Pirogova
This experimental study evaluates the effects of low power microwave radiation on the growth rate of yeast Saccharomyces cerevisiae strains type II, exposed to the microwaves (MW) at the frequencies of 1800 MHz and 2100 MHz and the selected powers of −10 dBm, 0 dBm and 17 dBm using the Transverse Electro-Magnetic (TEM) cell. A comparative analysis of changes, induced by MW exposures at the particular frequencies and powers, on the growth rate of the irradiated yeast cells vs. control group was performed. The findings reveal that the selected MW exposures affected the rate of yeast cells growth. To evaluate the dependence of yeast cell growth rate on MW exposures' frequency and power, Chi-square Test was performed. The results showed that the MW radiations parameters (frequency and power) contribute independently to modulating effects observed in the yeast cells growth.
{"title":"The effects of low power microwaves at 1800 MHz and 2100 MHz on yeast cells growth","authors":"Sohni Jain, Vuk Vojisaveljevic, E. Pirogova","doi":"10.1109/IMARC.2016.7939623","DOIUrl":"https://doi.org/10.1109/IMARC.2016.7939623","url":null,"abstract":"This experimental study evaluates the effects of low power microwave radiation on the growth rate of yeast Saccharomyces cerevisiae strains type II, exposed to the microwaves (MW) at the frequencies of 1800 MHz and 2100 MHz and the selected powers of −10 dBm, 0 dBm and 17 dBm using the Transverse Electro-Magnetic (TEM) cell. A comparative analysis of changes, induced by MW exposures at the particular frequencies and powers, on the growth rate of the irradiated yeast cells vs. control group was performed. The findings reveal that the selected MW exposures affected the rate of yeast cells growth. To evaluate the dependence of yeast cell growth rate on MW exposures' frequency and power, Chi-square Test was performed. The results showed that the MW radiations parameters (frequency and power) contribute independently to modulating effects observed in the yeast cells growth.","PeriodicalId":341661,"journal":{"name":"2016 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134430690","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 : 2016-12-01DOI: 10.1109/IMARC.2016.7939626
D. Ghosh, G. Kumar
This paper proposes two new tightly coupled 6 dB microstrip couplers for two different frequency bands with high isolation and good load dynamic range. The couplers employ quadrature mode and odd mode suppression to achieve high isolation. The first proposed coupler uses modified three branch couplers, while the second coupler uses Wilkinson power divider and rat race coupler. The measured isolation of the first coupler is above 40 dB from 723MHz to 1.2GHz, and the second coupler has isolation better than 35 dB from 1.6 to 2.6 GHz. The couplers have load dynamic ranges of 28—45 dB and 21—32 dB, from 750MHz to 1.15 GHz, and 1.7 to 2.6 GHz, respectively. The high dynamic range of these two couplers make them suitable for load sensing applications.
{"title":"Asymmetric high isolation 6 dB microstrip couplers for load sensing applications","authors":"D. Ghosh, G. Kumar","doi":"10.1109/IMARC.2016.7939626","DOIUrl":"https://doi.org/10.1109/IMARC.2016.7939626","url":null,"abstract":"This paper proposes two new tightly coupled 6 dB microstrip couplers for two different frequency bands with high isolation and good load dynamic range. The couplers employ quadrature mode and odd mode suppression to achieve high isolation. The first proposed coupler uses modified three branch couplers, while the second coupler uses Wilkinson power divider and rat race coupler. The measured isolation of the first coupler is above 40 dB from 723MHz to 1.2GHz, and the second coupler has isolation better than 35 dB from 1.6 to 2.6 GHz. The couplers have load dynamic ranges of 28—45 dB and 21—32 dB, from 750MHz to 1.15 GHz, and 1.7 to 2.6 GHz, respectively. The high dynamic range of these two couplers make them suitable for load sensing applications.","PeriodicalId":341661,"journal":{"name":"2016 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124479447","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 : 2016-12-01DOI: 10.1109/IMARC.2016.7939627
B. Biswas, G. Kumar
Design and development of a 14.25 GHz to 57 GHz frequency quadrupler has been presented in this paper using GaAs/InGaAs/AlGaAs based pseudomorphic High Electron Mobility Transistor (pHEMT) in a single-stage, Monolithic Microwave Integrated Circuit (MMIC). Fabricated MMIC chip has achieved 5.2 dB of conversion loss at 57 GHz for 0 dBm of input power at 14.25 GHz. Saturated output power is −4.5 dBm without any output amplifier stage. Fractional bandwidth has been obtained as 7%, while output power variation is within 5 dB. DC power consumption of the circuit is only 60 mW. Fundamental and other unwanted harmonic rejection is in excess of 25 dBc. Highly stable and high quality output spectrum of the frequency quadrupler makes it suitable for Millimeter Wave (MMW) transceiver application.
{"title":"A V-band High performance single-stage MMIC frequency quadrupler","authors":"B. Biswas, G. Kumar","doi":"10.1109/IMARC.2016.7939627","DOIUrl":"https://doi.org/10.1109/IMARC.2016.7939627","url":null,"abstract":"Design and development of a 14.25 GHz to 57 GHz frequency quadrupler has been presented in this paper using GaAs/InGaAs/AlGaAs based pseudomorphic High Electron Mobility Transistor (pHEMT) in a single-stage, Monolithic Microwave Integrated Circuit (MMIC). Fabricated MMIC chip has achieved 5.2 dB of conversion loss at 57 GHz for 0 dBm of input power at 14.25 GHz. Saturated output power is −4.5 dBm without any output amplifier stage. Fractional bandwidth has been obtained as 7%, while output power variation is within 5 dB. DC power consumption of the circuit is only 60 mW. Fundamental and other unwanted harmonic rejection is in excess of 25 dBc. Highly stable and high quality output spectrum of the frequency quadrupler makes it suitable for Millimeter Wave (MMW) transceiver application.","PeriodicalId":341661,"journal":{"name":"2016 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130952030","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 : 2016-12-01DOI: 10.1109/IMARC.2016.7939631
C. Viegas, B. Alderman, C. Pérez-Moreno, J. Powell, C. Duff, R. Sloan
This paper presents the design and thermal analysis of a high-power Schottky diode frequency doubler at 160 GHz. The design is capable of achieving ∼10% 3 dB bandwidth with a peak conversion efficiency of ∼25% for an input power of 100 mW at 295 K. Thermal characterization of the design includes modelling and measurement of the power dissipation in the discrete diode under different temperatures. The results obtained from the experiments have been validated by a physics-based electro-thermal simulator for Schottky diodes.
{"title":"Design and thermal analysis of a high-power frequency doubler at 160 GHz","authors":"C. Viegas, B. Alderman, C. Pérez-Moreno, J. Powell, C. Duff, R. Sloan","doi":"10.1109/IMARC.2016.7939631","DOIUrl":"https://doi.org/10.1109/IMARC.2016.7939631","url":null,"abstract":"This paper presents the design and thermal analysis of a high-power Schottky diode frequency doubler at 160 GHz. The design is capable of achieving ∼10% 3 dB bandwidth with a peak conversion efficiency of ∼25% for an input power of 100 mW at 295 K. Thermal characterization of the design includes modelling and measurement of the power dissipation in the discrete diode under different temperatures. The results obtained from the experiments have been validated by a physics-based electro-thermal simulator for Schottky diodes.","PeriodicalId":341661,"journal":{"name":"2016 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121797898","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 : 2016-12-01DOI: 10.1109/IMARC.2016.7939635
Satyajit Panda, Z. Akhter, M. Akhtar
A novel artificial neural network (ANN) based approach for the microwave subsurface imaging of reinforced concrete structures is proposed. The proposed technique facilitates the detection of the inner configuration of test structures, and is based on measurement of reflection data using a Ka-band waveguide (WR-28) along with the network analyzer. The waveguide is directly placed in contact with the test structure, and the whole sample is scanned by moving the waveguide holder along its surface in order to measure the reflection data at various positions. The training data for the ANN is generated by simulating the complete measurement setup in the CST Microwave Studio with a typical concrete specimen. The actual measured reflection data is then fed to the previously trained ANN to produce the subsurface image of the test structure. The proposed system is validated by imaging different concrete samples using both simulated and experimental data.
{"title":"Subsurface imaging of concrete structures using neural network approach","authors":"Satyajit Panda, Z. Akhter, M. Akhtar","doi":"10.1109/IMARC.2016.7939635","DOIUrl":"https://doi.org/10.1109/IMARC.2016.7939635","url":null,"abstract":"A novel artificial neural network (ANN) based approach for the microwave subsurface imaging of reinforced concrete structures is proposed. The proposed technique facilitates the detection of the inner configuration of test structures, and is based on measurement of reflection data using a Ka-band waveguide (WR-28) along with the network analyzer. The waveguide is directly placed in contact with the test structure, and the whole sample is scanned by moving the waveguide holder along its surface in order to measure the reflection data at various positions. The training data for the ANN is generated by simulating the complete measurement setup in the CST Microwave Studio with a typical concrete specimen. The actual measured reflection data is then fed to the previously trained ANN to produce the subsurface image of the test structure. The proposed system is validated by imaging different concrete samples using both simulated and experimental data.","PeriodicalId":341661,"journal":{"name":"2016 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133298845","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 : 2016-12-01DOI: 10.1109/IMARC.2016.7939637
P. K. Varshney, N. Tiwari, M. Akhtar
A novel SIW cavity based RF sensor is designed and developed for non-destructive testing (NDT) of dielectric and advanced composites at 1.5 GHz using the TE101 mode. The proposed sensor is fabricated on low cost FR-4 substrate, and excitation of fabricated sensor is done with 3.5mm SMA connectors. The material testing is performed using the cavity perturbation theory for real part of the permittivity, while the loss tangent is calculated using the numerical curve fitting technique. Several standard dielectrics are tested using the proposed sensor, and the results are compared with their reported values. The designed sensor is compact having more sensitivity in comparison to other SIW sensors reported in the past with error in the real permittivity within 5%.
{"title":"SIW cavity based compact RF sensor for testing of dielectrics and composites","authors":"P. K. Varshney, N. Tiwari, M. Akhtar","doi":"10.1109/IMARC.2016.7939637","DOIUrl":"https://doi.org/10.1109/IMARC.2016.7939637","url":null,"abstract":"A novel SIW cavity based RF sensor is designed and developed for non-destructive testing (NDT) of dielectric and advanced composites at 1.5 GHz using the TE101 mode. The proposed sensor is fabricated on low cost FR-4 substrate, and excitation of fabricated sensor is done with 3.5mm SMA connectors. The material testing is performed using the cavity perturbation theory for real part of the permittivity, while the loss tangent is calculated using the numerical curve fitting technique. Several standard dielectrics are tested using the proposed sensor, and the results are compared with their reported values. The designed sensor is compact having more sensitivity in comparison to other SIW sensors reported in the past with error in the real permittivity within 5%.","PeriodicalId":341661,"journal":{"name":"2016 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124481770","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 : 2016-12-01DOI: 10.1109/IMARC.2016.7939610
N. Subramani, J. Nallatamby, A. Sahoo, R. Sommet, R. Quéré, B. Bindu
A simple analytical model which validates both intrinsic and extrinsic current-voltage characteristics of AlGaN/GaN HEMT is presented. The dependence of spontaneous and piezoelectric polarization effects at the heterointerface, applied gate bias and Al mole fraction of AlGaN layer have been taken into account for estimating the two-dimensional electron gas (2DEG) density and current characteristics. The polynomial approximation which relates EF and sheet carrier density simplifies the model for all regions of operation i.e., from subthreshold to strong inversion region. The effect of parasitic source and drain resistance are considered to predict the extrinsic HEMT characteristics. The results obtained from the analytical model are compared with experimental data and TCAD numerical simulation results, and shows good agreement, thereby proving the validity of the model.
{"title":"A physics based analytical model and numerical simulation for current-voltage characteristics of microwave power AlGaN/GaN HEMT","authors":"N. Subramani, J. Nallatamby, A. Sahoo, R. Sommet, R. Quéré, B. Bindu","doi":"10.1109/IMARC.2016.7939610","DOIUrl":"https://doi.org/10.1109/IMARC.2016.7939610","url":null,"abstract":"A simple analytical model which validates both intrinsic and extrinsic current-voltage characteristics of AlGaN/GaN HEMT is presented. The dependence of spontaneous and piezoelectric polarization effects at the heterointerface, applied gate bias and Al mole fraction of AlGaN layer have been taken into account for estimating the two-dimensional electron gas (2DEG) density and current characteristics. The polynomial approximation which relates EF and sheet carrier density simplifies the model for all regions of operation i.e., from subthreshold to strong inversion region. The effect of parasitic source and drain resistance are considered to predict the extrinsic HEMT characteristics. The results obtained from the analytical model are compared with experimental data and TCAD numerical simulation results, and shows good agreement, thereby proving the validity of the model.","PeriodicalId":341661,"journal":{"name":"2016 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"146 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116730318","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 : 2016-12-01DOI: 10.1109/IMARC.2016.7939622
S. Bhattacharjee, M. Mitra, S. Chaudhuri
A novel uni-planar artificial magnetic conductor (AMC) structure ground plane with optimum sensitivity to incident angle is proposed for body centric communications over the industrial scientific medical (ISM) band (2.4–2.5 GHz) and 4G (Long-term evolution) LTE band 7 (2.5–2.69 GHz). The small variation of the reflection phase with different incidence angle is favorable for approximately stable radiation performance near the prescribed band with maximized in-phase reflections for TE and TM polarizations. The impedance mismatch is minimized considerably when the antenna is placed over human body with the reduction of coupling between them through the AMC grounded structure. Overall the structure is successful in reducing the specific absorption rate (SAR) and enhancing the bandwidth over the singly antenna.
{"title":"Improved matching and SAR reduction with little angular instable AMC based ground plane","authors":"S. Bhattacharjee, M. Mitra, S. Chaudhuri","doi":"10.1109/IMARC.2016.7939622","DOIUrl":"https://doi.org/10.1109/IMARC.2016.7939622","url":null,"abstract":"A novel uni-planar artificial magnetic conductor (AMC) structure ground plane with optimum sensitivity to incident angle is proposed for body centric communications over the industrial scientific medical (ISM) band (2.4–2.5 GHz) and 4G (Long-term evolution) LTE band 7 (2.5–2.69 GHz). The small variation of the reflection phase with different incidence angle is favorable for approximately stable radiation performance near the prescribed band with maximized in-phase reflections for TE and TM polarizations. The impedance mismatch is minimized considerably when the antenna is placed over human body with the reduction of coupling between them through the AMC grounded structure. Overall the structure is successful in reducing the specific absorption rate (SAR) and enhancing the bandwidth over the singly antenna.","PeriodicalId":341661,"journal":{"name":"2016 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125385072","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 : 2016-12-01DOI: 10.1109/IMARC.2016.7939636
Muhammed Shafi K. T., Abhishek Kumar Jha, M. Akhtar
In this paper, a non destructive technique is presented for detection of adulteration in common edible oils using the proposed microwave planar resonant sensor. The proposed sensor is operating in the ISM (industrial, scientific and medical) frequency band of 5.85 GHz. The sensor is designed using the full wave electromagnetic solver, the CST Microwave Studio, and an empirical model of the proposed sensor is developed for the accurate calculation of complex permittivity of standard edible oil samples under test in terms of the resonant frequency under loaded condition. The developed model is then used to detect the percentage adulteration of contaminants in the pure edible oil samples. The designed resonant sensor is fabricated on a 1.6 mm FR4 substrate. A sample container made of borosilicate glass is specially designed to make the overall procedure to be non-contacting and nondestructive. The fabricated sensor is finally tested for detecting adulteration with different concentration levels in edible oils.
{"title":"Nondestructive technique for detection of adulteration in edible oils using planar RF sensor","authors":"Muhammed Shafi K. T., Abhishek Kumar Jha, M. Akhtar","doi":"10.1109/IMARC.2016.7939636","DOIUrl":"https://doi.org/10.1109/IMARC.2016.7939636","url":null,"abstract":"In this paper, a non destructive technique is presented for detection of adulteration in common edible oils using the proposed microwave planar resonant sensor. The proposed sensor is operating in the ISM (industrial, scientific and medical) frequency band of 5.85 GHz. The sensor is designed using the full wave electromagnetic solver, the CST Microwave Studio, and an empirical model of the proposed sensor is developed for the accurate calculation of complex permittivity of standard edible oil samples under test in terms of the resonant frequency under loaded condition. The developed model is then used to detect the percentage adulteration of contaminants in the pure edible oil samples. The designed resonant sensor is fabricated on a 1.6 mm FR4 substrate. A sample container made of borosilicate glass is specially designed to make the overall procedure to be non-contacting and nondestructive. The fabricated sensor is finally tested for detecting adulteration with different concentration levels in edible oils.","PeriodicalId":341661,"journal":{"name":"2016 IEEE MTT-S International Microwave and RF Conference (IMaRC)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125524390","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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