2020 Joint Conference of the IEEE International Frequency Control Symposium and International Symposium on Applications of Ferroelectrics (IFCS-ISAF)最新文献
Pub Date : 2020-07-01DOI: 10.1109/IFCS-ISAF41089.2020.9234876
T. Imaike, Akito Shirai
In this paper, we propose a new method to improve measurement resolution of QCM (quartz crystal microbalances). In the proposed method, the oscillation waveform of the crystal oscillator is directly captured by an analog to digital converters, and the phase is calculated by digital computation. The mass of the object is detected by calculating the instantaneous frequency by time differentiation of the time-series phase information. Therefore, compared to the method using a frequency counter, there is no waiting time due to the gate time, therefore high-speed mass detection is possible. As a result of the experiment, it was confirmed that the measurement resolution was improved compared to the method using the frequency counter.
{"title":"Fully Digital QCM using Twin Quartz Sensor","authors":"T. Imaike, Akito Shirai","doi":"10.1109/IFCS-ISAF41089.2020.9234876","DOIUrl":"https://doi.org/10.1109/IFCS-ISAF41089.2020.9234876","url":null,"abstract":"In this paper, we propose a new method to improve measurement resolution of QCM (quartz crystal microbalances). In the proposed method, the oscillation waveform of the crystal oscillator is directly captured by an analog to digital converters, and the phase is calculated by digital computation. The mass of the object is detected by calculating the instantaneous frequency by time differentiation of the time-series phase information. Therefore, compared to the method using a frequency counter, there is no waiting time due to the gate time, therefore high-speed mass detection is possible. As a result of the experiment, it was confirmed that the measurement resolution was improved compared to the method using the frequency counter.","PeriodicalId":6872,"journal":{"name":"2020 Joint Conference of the IEEE International Frequency Control Symposium and International Symposium on Applications of Ferroelectrics (IFCS-ISAF)","volume":"1 1","pages":"1-2"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83092727","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 : 2020-07-01DOI: 10.1109/IFCS-ISAF41089.2020.9234880
F. Constantin
Two-photon rotational spectroscopy of cold trapped HD+ ions may be exploited for characterization of the magnitude and orientation of a static magnetic field in the ion trap. The experimental setup and the approach for calibration of the magnetic field vector are described. A sensitivity at the 10−11 T level may be reached with Zeeman spectroscopy of a hyperfine component of the $(mathrm{v},mathrm{L}) =(0,0)rightarrow(0,2)$ transition. The orientation of a magnetic field with a magnitude at the $1 mu mathrm{T}$ level may be characterized with an uncertainty better than 30 mrad.
冷阱HD+离子的双光子旋转光谱可以用来表征离子阱中静态磁场的大小和方向。介绍了实验装置和磁场矢量的标定方法。用塞曼光谱对$(mathrm{v},mathrm{L}) =(0,0)rightarrow(0,2)$跃迁的超精细组分可以达到10−11 T水平的灵敏度。量级为$1 mu mathrm{T}$级的磁场的方向可以用优于30 mrad的不确定度来表征。
{"title":"Characterization of a Static Magnetic Field with Two-Photon Rotational Spectroscopy of Cold Trapped HD+","authors":"F. Constantin","doi":"10.1109/IFCS-ISAF41089.2020.9234880","DOIUrl":"https://doi.org/10.1109/IFCS-ISAF41089.2020.9234880","url":null,"abstract":"Two-photon rotational spectroscopy of cold trapped HD+ ions may be exploited for characterization of the magnitude and orientation of a static magnetic field in the ion trap. The experimental setup and the approach for calibration of the magnetic field vector are described. A sensitivity at the 10−11 T level may be reached with Zeeman spectroscopy of a hyperfine component of the $(mathrm{v},mathrm{L}) =(0,0)rightarrow(0,2)$ transition. The orientation of a magnetic field with a magnitude at the $1 mu mathrm{T}$ level may be characterized with an uncertainty better than 30 mrad.","PeriodicalId":6872,"journal":{"name":"2020 Joint Conference of the IEEE International Frequency Control Symposium and International Symposium on Applications of Ferroelectrics (IFCS-ISAF)","volume":"107 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73535826","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 : 2020-07-01DOI: 10.1109/IFCS-ISAF41089.2020.9234888
A. Hati, C. Nelson
Multipath interference can be a challenging problem in the determination of accurate outdoor and indoor localization. There are methods that exist to mitigate this problem by extracting the multipath parameters, namely, differential attenuation, carrier phase shift, and differential time-delay. One method is to transmit a narrow pulse and extract these parameters from the impulse response of the channel. Another well-established method is to use frequency dependent amplitude fading of a swept sinusoid for multipath parameters extraction. In this paper, we used the second technique for the suppression of multipath distortion. We implemented this scheme with an Ettus B120 software defined radio (SDR) and observed more than a factor of 8 (18 dB) reduction of multipath distortion under different indoor environments; our findings are supported by both simulation as well as experimental results.
{"title":"Multipath Parameter Extraction and Correction from Frequency Dependent Amplitude Fading","authors":"A. Hati, C. Nelson","doi":"10.1109/IFCS-ISAF41089.2020.9234888","DOIUrl":"https://doi.org/10.1109/IFCS-ISAF41089.2020.9234888","url":null,"abstract":"Multipath interference can be a challenging problem in the determination of accurate outdoor and indoor localization. There are methods that exist to mitigate this problem by extracting the multipath parameters, namely, differential attenuation, carrier phase shift, and differential time-delay. One method is to transmit a narrow pulse and extract these parameters from the impulse response of the channel. Another well-established method is to use frequency dependent amplitude fading of a swept sinusoid for multipath parameters extraction. In this paper, we used the second technique for the suppression of multipath distortion. We implemented this scheme with an Ettus B120 software defined radio (SDR) and observed more than a factor of 8 (18 dB) reduction of multipath distortion under different indoor environments; our findings are supported by both simulation as well as experimental results.","PeriodicalId":6872,"journal":{"name":"2020 Joint Conference of the IEEE International Frequency Control Symposium and International Symposium on Applications of Ferroelectrics (IFCS-ISAF)","volume":"164 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75339373","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 : 2020-07-01DOI: 10.1109/IFCS-ISAF41089.2020.9234857
W. Qin, Yulong Ge, Wei Wang, Xuhai Yang
The research on the mitigation on the jump of the day boundary is a perpetual topic for the time-filed scholars. Compared to GPS, the results operated by multiple Global Navigation Satellite Systems (GNSSs) may alleviate the jump not remove the jump. Focused on this problem, the new algorithm is proposed as here: three-stated clock model is added to the observation, the characteristic of clock is fully recovered. The ambiguity should be initialized in the first epoch of each day for constraining jump fiercely to the ambiguity parameter so as to get a clean receiver clock parameter. In order to validate whether the approach works, six kinds of combinations of three stations were analyzed. Compared to traditional solutions, the jump of three stations is removed completely. With respect to the frequency stability, the new model has an absolute superiority than that of traditional solution, particularly in the short-term, the maximal improvement is up to 80%.
{"title":"An Approach for Mitigating PPP Day Boundary with Clock Stochastic Model","authors":"W. Qin, Yulong Ge, Wei Wang, Xuhai Yang","doi":"10.1109/IFCS-ISAF41089.2020.9234857","DOIUrl":"https://doi.org/10.1109/IFCS-ISAF41089.2020.9234857","url":null,"abstract":"The research on the mitigation on the jump of the day boundary is a perpetual topic for the time-filed scholars. Compared to GPS, the results operated by multiple Global Navigation Satellite Systems (GNSSs) may alleviate the jump not remove the jump. Focused on this problem, the new algorithm is proposed as here: three-stated clock model is added to the observation, the characteristic of clock is fully recovered. The ambiguity should be initialized in the first epoch of each day for constraining jump fiercely to the ambiguity parameter so as to get a clean receiver clock parameter. In order to validate whether the approach works, six kinds of combinations of three stations were analyzed. Compared to traditional solutions, the jump of three stations is removed completely. With respect to the frequency stability, the new model has an absolute superiority than that of traditional solution, particularly in the short-term, the maximal improvement is up to 80%.","PeriodicalId":6872,"journal":{"name":"2020 Joint Conference of the IEEE International Frequency Control Symposium and International Symposium on Applications of Ferroelectrics (IFCS-ISAF)","volume":"11 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77066925","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 : 2020-07-01DOI: 10.1109/IFCS-ISAF41089.2020.9234922
K. Irie, Jun-ichi Arai, Manabu Ito, Toshiyuki Shinotsuka, Manabu Ishikawa, S. Wakamatsu
This paper describes a high stability ultra-miniature size OCXO operating within wide temperature range using a ASIC with a built-in oven for OCXO. The ASIC realized that the OCXO could be extremely downsized and the maximum operating temperature is getting higher because it has almost all functions including a built-in oven which OCXOs should have. We have achieved about +/−5 ppb in a range of −40 to +95 °C and obtained excellent temperature slope characteristics for $7.0times 5.0text{mm}$ size package.
{"title":"High Stability Ultra-Miniature Size OCXO Operating within Wide Temperature Range: Using ASIC with Built-in Oven for OCXO","authors":"K. Irie, Jun-ichi Arai, Manabu Ito, Toshiyuki Shinotsuka, Manabu Ishikawa, S. Wakamatsu","doi":"10.1109/IFCS-ISAF41089.2020.9234922","DOIUrl":"https://doi.org/10.1109/IFCS-ISAF41089.2020.9234922","url":null,"abstract":"This paper describes a high stability ultra-miniature size OCXO operating within wide temperature range using a ASIC with a built-in oven for OCXO. The ASIC realized that the OCXO could be extremely downsized and the maximum operating temperature is getting higher because it has almost all functions including a built-in oven which OCXOs should have. We have achieved about +/−5 ppb in a range of −40 to +95 °C and obtained excellent temperature slope characteristics for $7.0times 5.0text{mm}$ size package.","PeriodicalId":6872,"journal":{"name":"2020 Joint Conference of the IEEE International Frequency Control Symposium and International Symposium on Applications of Ferroelectrics (IFCS-ISAF)","volume":"2 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78409347","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 : 2020-07-01DOI: 10.1109/IFCS-ISAF41089.2020.9234873
M. Siccardi, T. T. Thai, D. Rovera, I. Sesia
Many timing laboratories employ the Two-Way Satellite Time and Frequency Transfer (TWSTFT) technique for the comparison of their high accuracy atomic clocks and time scales and contribute to the Coordinated Universal Time (UTC). Most laboratories use the SATRE (SAtellite Time and Ranging Equipment) modems developed by TimeTech, which is currently the sole European manufacturer of TWSTFT modems. Some laboratories also participate in the 2016 BIPM pilot study on the Software-Defined Radio (SDR) receiver for TWSTFT which was proven to reduce the diurnal variation seen on “traditional” SATRE links. In this work, we developed a prototype for transmitting TWSTFT signal which is compatible with both SATRE modems and SDR receivers and present a preliminary assessment of its compatibility and performance.
{"title":"A TWSTFT Transmitter Prototype Compatible with SDR Receivers and SATRE Modems","authors":"M. Siccardi, T. T. Thai, D. Rovera, I. Sesia","doi":"10.1109/IFCS-ISAF41089.2020.9234873","DOIUrl":"https://doi.org/10.1109/IFCS-ISAF41089.2020.9234873","url":null,"abstract":"Many timing laboratories employ the Two-Way Satellite Time and Frequency Transfer (TWSTFT) technique for the comparison of their high accuracy atomic clocks and time scales and contribute to the Coordinated Universal Time (UTC). Most laboratories use the SATRE (SAtellite Time and Ranging Equipment) modems developed by TimeTech, which is currently the sole European manufacturer of TWSTFT modems. Some laboratories also participate in the 2016 BIPM pilot study on the Software-Defined Radio (SDR) receiver for TWSTFT which was proven to reduce the diurnal variation seen on “traditional” SATRE links. In this work, we developed a prototype for transmitting TWSTFT signal which is compatible with both SATRE modems and SDR receivers and present a preliminary assessment of its compatibility and performance.","PeriodicalId":6872,"journal":{"name":"2020 Joint Conference of the IEEE International Frequency Control Symposium and International Symposium on Applications of Ferroelectrics (IFCS-ISAF)","volume":"204 1","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77030387","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 : 2020-07-01DOI: 10.1109/ifcs-isaf41089.2020.9234921
{"title":"Copyright","authors":"","doi":"10.1109/ifcs-isaf41089.2020.9234921","DOIUrl":"https://doi.org/10.1109/ifcs-isaf41089.2020.9234921","url":null,"abstract":"","PeriodicalId":6872,"journal":{"name":"2020 Joint Conference of the IEEE International Frequency Control Symposium and International Symposium on Applications of Ferroelectrics (IFCS-ISAF)","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78457383","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 : 2020-07-01DOI: 10.1109/IFCS-ISAF41089.2020.9234924
Dandan Liu, Jun Ruan, Sichen Fan, Hui Zhang, Yong Guan, Xinliang Wang, Junru Shi, Yan Yang, Yang Bai, Shougang Zhang
Frequency measurement and comparison with TAI of NTSC-F1 is presented in the paper. Automatical evaluation system of cesium fountain clock is designed to correct the systematic frequency biases in real time. The estimation of the average frequency between H-maser donated as 296 in Circular T report and NTSC-F1 is obtained over the frequency data after correcting all the shifts. Then the frequency offset between NTSC-F1 and TAI is given with the uncertainty of $2.9times 10^{-15}$ including the uncertainty between UTC and UTC(NTSC).
{"title":"Comparison with TAI of NTSC-F1","authors":"Dandan Liu, Jun Ruan, Sichen Fan, Hui Zhang, Yong Guan, Xinliang Wang, Junru Shi, Yan Yang, Yang Bai, Shougang Zhang","doi":"10.1109/IFCS-ISAF41089.2020.9234924","DOIUrl":"https://doi.org/10.1109/IFCS-ISAF41089.2020.9234924","url":null,"abstract":"Frequency measurement and comparison with TAI of NTSC-F1 is presented in the paper. Automatical evaluation system of cesium fountain clock is designed to correct the systematic frequency biases in real time. The estimation of the average frequency between H-maser donated as 296 in Circular T report and NTSC-F1 is obtained over the frequency data after correcting all the shifts. Then the frequency offset between NTSC-F1 and TAI is given with the uncertainty of $2.9times 10^{-15}$ including the uncertainty between UTC and UTC(NTSC).","PeriodicalId":6872,"journal":{"name":"2020 Joint Conference of the IEEE International Frequency Control Symposium and International Symposium on Applications of Ferroelectrics (IFCS-ISAF)","volume":"49 1","pages":"1-2"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80715940","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 : 2020-07-01DOI: 10.1109/IFCS-ISAF41089.2020.9234810
M. Šimėnas, S. Balčiu̅nas, Š. Svirskas, M. Kinka, V. Samulionis, R. Grigalaitis, J. Banys, A. Gągor, M. Ma̧czka, A. Garbaras, A. Sieradzki
Here, we present a multitechnique experimental study of structural phase transitions and dipolar dynamics in the novel mixed methylammonium (MA)/dimethylammonium (DMA) MA1-xDMAxPbBr3 hybrid perovskites. The obtained results demonstrate a suppression of the structural phase transitions and stabilization of the cubic phase even for a small amount of DMA cations. For high DMA concentration, we observe a disappearance of the structural phase transitions and emergence of a glassy phase of electric dipoles.
{"title":"Peculiarities of Dipolar Ordering in Mixed Cation Halide Perovskites","authors":"M. Šimėnas, S. Balčiu̅nas, Š. Svirskas, M. Kinka, V. Samulionis, R. Grigalaitis, J. Banys, A. Gągor, M. Ma̧czka, A. Garbaras, A. Sieradzki","doi":"10.1109/IFCS-ISAF41089.2020.9234810","DOIUrl":"https://doi.org/10.1109/IFCS-ISAF41089.2020.9234810","url":null,"abstract":"Here, we present a multitechnique experimental study of structural phase transitions and dipolar dynamics in the novel mixed methylammonium (MA)/dimethylammonium (DMA) MA1-xDMAxPbBr3 hybrid perovskites. The obtained results demonstrate a suppression of the structural phase transitions and stabilization of the cubic phase even for a small amount of DMA cations. For high DMA concentration, we observe a disappearance of the structural phase transitions and emergence of a glassy phase of electric dipoles.","PeriodicalId":6872,"journal":{"name":"2020 Joint Conference of the IEEE International Frequency Control Symposium and International Symposium on Applications of Ferroelectrics (IFCS-ISAF)","volume":"40 1","pages":"1-2"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81378952","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 : 2020-07-01DOI: 10.1109/IFCS-ISAF41089.2020.9234852
K. Bhosale, Gayathri Pillai, Sheng-Shian Li
In this work, we explore the generation of higher order harmonics in an electrostatically actuated wide-width beam resonator fabricated by a CMOS-MEMS Titanium Nitride Composite (TiN-C) platform. The explored TiN-C platform can achieve a gap of 400 nm with high transduction efficiency, low motional resistance ($R_{m}$) and enhanced frequency stability. A record-high Radius of Curvature (R.O.C of 11.9 cm) of the fabricated wide-width pseudo free-free beam is achieved among CMOS-MEMS counterparts. The fundamental mode is measured at a resonance frequency of 9.8 MHz. The second and the third higher order harmonics are observed when the resonator is excited at its fundamental flexural mode in the non-linear region. A varying AC voltage drives the resonator from the linear regime into non-linear regime for an applied DC bias of 80 V. The presence of harmonics is confirmed electrically and optically through measurement using the Spectrum Analyzer and the Laser Doppler Vibrometer (LDV) respectively.
{"title":"Nonlinearity Driven Higher Order Harmonics in CMOS-MEMS Resonators","authors":"K. Bhosale, Gayathri Pillai, Sheng-Shian Li","doi":"10.1109/IFCS-ISAF41089.2020.9234852","DOIUrl":"https://doi.org/10.1109/IFCS-ISAF41089.2020.9234852","url":null,"abstract":"In this work, we explore the generation of higher order harmonics in an electrostatically actuated wide-width beam resonator fabricated by a CMOS-MEMS Titanium Nitride Composite (TiN-C) platform. The explored TiN-C platform can achieve a gap of 400 nm with high transduction efficiency, low motional resistance ($R_{m}$) and enhanced frequency stability. A record-high Radius of Curvature (R.O.C of 11.9 cm) of the fabricated wide-width pseudo free-free beam is achieved among CMOS-MEMS counterparts. The fundamental mode is measured at a resonance frequency of 9.8 MHz. The second and the third higher order harmonics are observed when the resonator is excited at its fundamental flexural mode in the non-linear region. A varying AC voltage drives the resonator from the linear regime into non-linear regime for an applied DC bias of 80 V. The presence of harmonics is confirmed electrically and optically through measurement using the Spectrum Analyzer and the Laser Doppler Vibrometer (LDV) respectively.","PeriodicalId":6872,"journal":{"name":"2020 Joint Conference of the IEEE International Frequency Control Symposium and International Symposium on Applications of Ferroelectrics (IFCS-ISAF)","volume":"22 1","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81679185","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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