Pub Date : 2015-04-12DOI: 10.1109/FCS.2015.7138948
K. Liang, A. Zhang, Zhiqiang Yang, Weiliang Chen, Weibo Wang, Long Bai, Guitao Fu
TWOTFT has been studied and implemented according to the similar principles to those of TWSTFT. We initially constructed the experiment system for TWOTFT and done some experiments such as time and frequency transfer through the laboratory optical fiber and the real optical fiber links including the real link with 109 km length at NIM. We can get the time stability of less than 6 ps/s and 0.9 ps/100s, and the standard uncertainty of less than 200 ps for time transfer.
{"title":"Preliminary time transfer through optical fiber at NIM","authors":"K. Liang, A. Zhang, Zhiqiang Yang, Weiliang Chen, Weibo Wang, Long Bai, Guitao Fu","doi":"10.1109/FCS.2015.7138948","DOIUrl":"https://doi.org/10.1109/FCS.2015.7138948","url":null,"abstract":"TWOTFT has been studied and implemented according to the similar principles to those of TWSTFT. We initially constructed the experiment system for TWOTFT and done some experiments such as time and frequency transfer through the laboratory optical fiber and the real optical fiber links including the real link with 109 km length at NIM. We can get the time stability of less than 6 ps/s and 0.9 ps/100s, and the standard uncertainty of less than 200 ps for time transfer.","PeriodicalId":57667,"journal":{"name":"时间频率公报","volume":"1 1","pages":"742-746"},"PeriodicalIF":0.0,"publicationDate":"2015-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91295842","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 : 2015-04-12DOI: 10.1109/FCS.2015.7138841
L. Sliwczynski, P. Krehlik, M. Lipinski, K. Turza, A. Binczewski
In the paper we are presenting the results of the experiments we performed with sending the frequency signals (10 MHz) to the remote location exploiting the optical dense wavelength division multiplexed telecommunication network. To stabilize the phase of the frequency signal we applied the approach with the electronic stabilization of the propagation delay. We measured the residual instability resulting from the fact that in a telecommunication network the signals in the forward and backward direction do not share the same fiber and are transmitted through different pieces of equipment when passing through reconfigurable optical add drop multiplexers or optical amplifiers. Our experiments show that results may depend substantially on the route of the link. For all tested links, however, the stability was better than the stability of the signal generated by commercial 5071A cesium standard. In case of one link even the stability better than stability of H-maser was observed for averaging times longer than 1000 s.
{"title":"Frequency distribution in delay-stabilized optical DWDM network over the distance of 3000 km","authors":"L. Sliwczynski, P. Krehlik, M. Lipinski, K. Turza, A. Binczewski","doi":"10.1109/FCS.2015.7138841","DOIUrl":"https://doi.org/10.1109/FCS.2015.7138841","url":null,"abstract":"In the paper we are presenting the results of the experiments we performed with sending the frequency signals (10 MHz) to the remote location exploiting the optical dense wavelength division multiplexed telecommunication network. To stabilize the phase of the frequency signal we applied the approach with the electronic stabilization of the propagation delay. We measured the residual instability resulting from the fact that in a telecommunication network the signals in the forward and backward direction do not share the same fiber and are transmitted through different pieces of equipment when passing through reconfigurable optical add drop multiplexers or optical amplifiers. Our experiments show that results may depend substantially on the route of the link. For all tested links, however, the stability was better than the stability of the signal generated by commercial 5071A cesium standard. In case of one link even the stability better than stability of H-maser was observed for averaging times longer than 1000 s.","PeriodicalId":57667,"journal":{"name":"时间频率公报","volume":"44 1","pages":"280-283"},"PeriodicalIF":0.0,"publicationDate":"2015-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85733946","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 : 2015-04-12DOI: 10.1109/FCS.2015.7138861
Qinghua Wang, F. Droz, P. Rochat
A robust clock ensemble is proposed for the time and frequency reference system to improve the robustness and performance of the system. Studies on the feasibility of hardware and algorithm approaches have been conducted. All clocks in the ensemble are locked in phase and frequency via the steering loop. The system performs corrections on the master clock in function of weighted averaging of clocks to generate one ensemble output, and the clock fault detection and compensation is implemented in real time with minimum three clocks powered. As the design has been demonstrated on an elegant breadboard of the Robust Onboard Frequency Reference Subsystem, this concept is proposed for the next-generation of Precise Timing Facility. Simulation results have demonstrated its capability and simplicity to provide a smooth and reliable timing or frequency output even in presence of clock feared events.
{"title":"Robust clock ensemble for time and frequency reference system","authors":"Qinghua Wang, F. Droz, P. Rochat","doi":"10.1109/FCS.2015.7138861","DOIUrl":"https://doi.org/10.1109/FCS.2015.7138861","url":null,"abstract":"A robust clock ensemble is proposed for the time and frequency reference system to improve the robustness and performance of the system. Studies on the feasibility of hardware and algorithm approaches have been conducted. All clocks in the ensemble are locked in phase and frequency via the steering loop. The system performs corrections on the master clock in function of weighted averaging of clocks to generate one ensemble output, and the clock fault detection and compensation is implemented in real time with minimum three clocks powered. As the design has been demonstrated on an elegant breadboard of the Robust Onboard Frequency Reference Subsystem, this concept is proposed for the next-generation of Precise Timing Facility. Simulation results have demonstrated its capability and simplicity to provide a smooth and reliable timing or frequency output even in presence of clock feared events.","PeriodicalId":57667,"journal":{"name":"时间频率公报","volume":"98 1","pages":"374-378"},"PeriodicalIF":0.0,"publicationDate":"2015-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73529147","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 : 2015-04-12DOI: 10.1109/FCS.2015.7138963
I. Procházka, J. Blažej, J. Kodet
Laser time transfer is and attractive technique to transfer time ground to space with picosecond precision and systematic errors on the level of tens of picoseconds. Recently the European Laser Timing experiment is under construction in the frame of the European Space Agency mission Atomic Clock Ensemble in Space. The objective of this laser time transfer is synchronization of the ground based clocks and the clock on board the International Space Station with picosecond precision and the accuracy better than 50 picoseconds We are reporting on a progress in identification and calibration of the biases associated to both ground and space segment. To characterize the delays of a ground segment the Calibration Device has been developed and tested. It enables to calibrate the ground based laser systems for their systematic timing biases. As a result the ground to ground time transfer in an ELT experiment should be accomplished with systematic errors not higher than 25 picoseconds. To determine the delays of a space segment the new calibration procedure has been designed and tested as well. The calibration test results will be presented.
{"title":"Identification and calibration of ground system biases in ground to space laser time transfer","authors":"I. Procházka, J. Blažej, J. Kodet","doi":"10.1109/FCS.2015.7138963","DOIUrl":"https://doi.org/10.1109/FCS.2015.7138963","url":null,"abstract":"Laser time transfer is and attractive technique to transfer time ground to space with picosecond precision and systematic errors on the level of tens of picoseconds. Recently the European Laser Timing experiment is under construction in the frame of the European Space Agency mission Atomic Clock Ensemble in Space. The objective of this laser time transfer is synchronization of the ground based clocks and the clock on board the International Space Station with picosecond precision and the accuracy better than 50 picoseconds We are reporting on a progress in identification and calibration of the biases associated to both ground and space segment. To characterize the delays of a ground segment the Calibration Device has been developed and tested. It enables to calibrate the ground based laser systems for their systematic timing biases. As a result the ground to ground time transfer in an ELT experiment should be accomplished with systematic errors not higher than 25 picoseconds. To determine the delays of a space segment the new calibration procedure has been designed and tested as well. The calibration test results will be presented.","PeriodicalId":57667,"journal":{"name":"时间频率公报","volume":"17 1","pages":"804-807"},"PeriodicalIF":0.0,"publicationDate":"2015-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86131407","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 : 2015-04-12DOI: 10.1109/FCS.2015.7138891
F. Fang, Weiliang Chen, Kun Liu, Nianfeng Liu, R. Suo, Tian-chu Li
We report the design of a new cesium fountain clock NIM6, which is under construction in NIM. Besides some improvements on the vacuum system, Ramsey cavity and microwave synthesizer to reduce the Type B uncertainty. Another major improvement on NIM6 is to collect more atoms from a MOT loading optical molasses and optical pumping to get a better signal to noise ratio at the detection. The atom distribution will be more uniform compared with a 2D MOT loading optical molasses, and the diameter of the cloud can be adjusted by the intensity and detuning of lights during the post cooling to keep the collisional-induced frequency shift low. The atom numbers can be further increased by a new de-pumping - optical pumping procedure to pump atoms to the |F=3, mF=0> clock state directly. With a new cryogenic sapphire oscillator (CSO) based frequency synthesizer, NIM6 is aiming to reach the quantum projection noise, thus leading to a reduced Type A uncertainty compared with NIM5.
{"title":"Design of the new NIM6 fountain with collecting atoms from a 3D MOT loading optical molasses","authors":"F. Fang, Weiliang Chen, Kun Liu, Nianfeng Liu, R. Suo, Tian-chu Li","doi":"10.1109/FCS.2015.7138891","DOIUrl":"https://doi.org/10.1109/FCS.2015.7138891","url":null,"abstract":"We report the design of a new cesium fountain clock NIM6, which is under construction in NIM. Besides some improvements on the vacuum system, Ramsey cavity and microwave synthesizer to reduce the Type B uncertainty. Another major improvement on NIM6 is to collect more atoms from a MOT loading optical molasses and optical pumping to get a better signal to noise ratio at the detection. The atom distribution will be more uniform compared with a 2D MOT loading optical molasses, and the diameter of the cloud can be adjusted by the intensity and detuning of lights during the post cooling to keep the collisional-induced frequency shift low. The atom numbers can be further increased by a new de-pumping - optical pumping procedure to pump atoms to the |F=3, mF=0> clock state directly. With a new cryogenic sapphire oscillator (CSO) based frequency synthesizer, NIM6 is aiming to reach the quantum projection noise, thus leading to a reduced Type A uncertainty compared with NIM5.","PeriodicalId":57667,"journal":{"name":"时间频率公报","volume":"52 1","pages":"492-494"},"PeriodicalIF":0.0,"publicationDate":"2015-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84993459","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 : 2015-04-12DOI: 10.1109/FCS.2015.7138893
V. Kalinin
Statistical simulation is used to evaluate performance of four different frequency estimators for interrogation of resonant wireless SAW sensors. The first one is based on DFT and quadratic interpolation, the second one employs a weighted least-squares estimate of the phase difference between signal samples. The third and the fourth methods use singular value decomposition and apply a weighted linear predictor in the case of constant sine wave amplitude and an iterative least squares method in the case of decaying sine wave. Numerical receiver model includes additive and phase noises, SAW response limiting, non-linear phase distortions and parasitic SAW responses. Experimental results are also obtained for all the four frequency estimators.
{"title":"Comparison of frequency estimators for interrogation of wireless resonant SAW sensors","authors":"V. Kalinin","doi":"10.1109/FCS.2015.7138893","DOIUrl":"https://doi.org/10.1109/FCS.2015.7138893","url":null,"abstract":"Statistical simulation is used to evaluate performance of four different frequency estimators for interrogation of resonant wireless SAW sensors. The first one is based on DFT and quadratic interpolation, the second one employs a weighted least-squares estimate of the phase difference between signal samples. The third and the fourth methods use singular value decomposition and apply a weighted linear predictor in the case of constant sine wave amplitude and an iterative least squares method in the case of decaying sine wave. Numerical receiver model includes additive and phase noises, SAW response limiting, non-linear phase distortions and parasitic SAW responses. Experimental results are also obtained for all the four frequency estimators.","PeriodicalId":57667,"journal":{"name":"时间频率公报","volume":"12 1","pages":"498-503"},"PeriodicalIF":0.0,"publicationDate":"2015-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85036790","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 : 2015-04-12DOI: 10.1109/FCS.2015.7138784
Yoshinori Takizawa, T. Shibata, Shinji Kashiwada, Yasuo Yamamoto, M. Esashi, Shuji Tanaka
SAW device is widely used in the various passive sensing application such as temperature, mechanical force and other various measurements. The SAW devices have relatively high the temperature dependency, thus in some applications, the multiple SAW sensors are used for the temperature compensation. In such a case, the communication between the sensor and controller is highly important. This paper describes the one channel communication with multiple SAW resonators for the measurement applications. The final target of this research is to investigate the near magnetic field wireless passive sensing capability using the continuous wave for higher response speed.
{"title":"Multiple SAW resonance sensing through one communication channel with multiple phase detectors","authors":"Yoshinori Takizawa, T. Shibata, Shinji Kashiwada, Yasuo Yamamoto, M. Esashi, Shuji Tanaka","doi":"10.1109/FCS.2015.7138784","DOIUrl":"https://doi.org/10.1109/FCS.2015.7138784","url":null,"abstract":"SAW device is widely used in the various passive sensing application such as temperature, mechanical force and other various measurements. The SAW devices have relatively high the temperature dependency, thus in some applications, the multiple SAW sensors are used for the temperature compensation. In such a case, the communication between the sensor and controller is highly important. This paper describes the one channel communication with multiple SAW resonators for the measurement applications. The final target of this research is to investigate the near magnetic field wireless passive sensing capability using the continuous wave for higher response speed.","PeriodicalId":57667,"journal":{"name":"时间频率公报","volume":"39 1","pages":"17-20"},"PeriodicalIF":0.0,"publicationDate":"2015-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85091812","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 : 2015-04-12DOI: 10.1109/FCS.2015.7138785
C. Affolderbach, G. Du, T. Bandi, A. Horsley, P. Treutlein, G. Mileti
We use a Ramsey-type interaction scheme to measure spatially-resolved images of the static magnetic field (C-field) amplitude Bdc applied across the Rb cell in the physics package of a high-performance vapor-cell atomic clock. Low field variations of <; 0.5% are found across the recorded images, and Fourier analysis of the data indicates low variations of Bdc also along the direction of laser propagation. Images of the T2 relaxation time are obtained in a similar way, and show a distribution that correlates with the Bdc distribution. This indicates inhomogeneous dephasing due to C-field gradients, which also results in spatial variation of the T2 time for the clock transition.
{"title":"Imaging the static magnetic field distribution in a vapor cell atomic clock","authors":"C. Affolderbach, G. Du, T. Bandi, A. Horsley, P. Treutlein, G. Mileti","doi":"10.1109/FCS.2015.7138785","DOIUrl":"https://doi.org/10.1109/FCS.2015.7138785","url":null,"abstract":"We use a Ramsey-type interaction scheme to measure spatially-resolved images of the static magnetic field (C-field) amplitude Bdc applied across the Rb cell in the physics package of a high-performance vapor-cell atomic clock. Low field variations of <; 0.5% are found across the recorded images, and Fourier analysis of the data indicates low variations of Bdc also along the direction of laser propagation. Images of the T2 relaxation time are obtained in a similar way, and show a distribution that correlates with the Bdc distribution. This indicates inhomogeneous dephasing due to C-field gradients, which also results in spatial variation of the T2 time for the clock transition.","PeriodicalId":57667,"journal":{"name":"时间频率公报","volume":"40 1","pages":"21-24"},"PeriodicalIF":0.0,"publicationDate":"2015-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87247605","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 : 2015-04-12DOI: 10.1109/FCS.2015.7138865
T. Kalkur, Milad Hmeda, A. Mansour, P. Alpay, Nick Sbockey, G. Tompa
A solidly mounted tunable barium strontium GaN/Sapphire substrate using a metalorganic solution deposition (MOSD) technique. An acoustic Bragg reflector was first formed on the GaN/sapphire substrate consisting of alternating layers of silicon dioxide and tantalum oxide deposited using a-spin on technique. Lower and upper electrodes were fabricated using sputter deposited platinum. The resonant frequency of the resonator could be tuned from 5.17 GHz to 5.20 GHz by applying a voltage of 8 V, resulting in tunability of about 0.6%. The quality factor of the resonator was found to depend on the applied voltage, with a maximum quality factor of 216 observed for an applied bias voltage of 8 V. The effective electromechanical coupling coefficient (kt2) of the resonator was found to be 13.1% at 8 V.
{"title":"Switchable and tunable resonators with barium strontium titanate on GaN/Sapphire substrates","authors":"T. Kalkur, Milad Hmeda, A. Mansour, P. Alpay, Nick Sbockey, G. Tompa","doi":"10.1109/FCS.2015.7138865","DOIUrl":"https://doi.org/10.1109/FCS.2015.7138865","url":null,"abstract":"A solidly mounted tunable barium strontium GaN/Sapphire substrate using a metalorganic solution deposition (MOSD) technique. An acoustic Bragg reflector was first formed on the GaN/sapphire substrate consisting of alternating layers of silicon dioxide and tantalum oxide deposited using a-spin on technique. Lower and upper electrodes were fabricated using sputter deposited platinum. The resonant frequency of the resonator could be tuned from 5.17 GHz to 5.20 GHz by applying a voltage of 8 V, resulting in tunability of about 0.6%. The quality factor of the resonator was found to depend on the applied voltage, with a maximum quality factor of 216 observed for an applied bias voltage of 8 V. The effective electromechanical coupling coefficient (kt2) of the resonator was found to be 13.1% at 8 V.","PeriodicalId":57667,"journal":{"name":"时间频率公报","volume":"44 1","pages":"392-395"},"PeriodicalIF":0.0,"publicationDate":"2015-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84424988","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 : 2015-04-12DOI: 10.1109/FCS.2015.7138901
Z. Ramshani, B. B. Narakathu, A. S. G. Reddy, M. Atashbar, J. T. Wabeke, S. Obare
In this study, a shear horizontal mode surface acoustic wave (SH-SAW) sensor, was designed and fabricated for the detection of heavy metals. The SH-SAW sensor was photolithographically fabricated by patterning gold (Au) interdigitated electrodes (IDE) and reflectors on the surface of a 64° YX-LiNbO3 based piezoelectric substrate. A flow cell, with a reservoir volume of 3 μl, which employs inlet and outlet ports for the microfluidic chamber and polydimethylsiloxane (PDMS) based microfluidic channels, was also designed and fabricated using acrylic material. Phenol and naphtho[2,3-a]dipyrido[3,2-h:2'3'-f] phenazine-5,18-dione (QDPPZ) were employed as the sensing layers for mercury and nickel ions, respectively. The frequency based response of the SH-SAW sensor demonstrated picomolar level detection for mercury nitrate (Hg(NO3)2) and nickel nitrate (Ni(NO3)2).
{"title":"SH-SAW-based sensor for heavy metal ion detection","authors":"Z. Ramshani, B. B. Narakathu, A. S. G. Reddy, M. Atashbar, J. T. Wabeke, S. Obare","doi":"10.1109/FCS.2015.7138901","DOIUrl":"https://doi.org/10.1109/FCS.2015.7138901","url":null,"abstract":"In this study, a shear horizontal mode surface acoustic wave (SH-SAW) sensor, was designed and fabricated for the detection of heavy metals. The SH-SAW sensor was photolithographically fabricated by patterning gold (Au) interdigitated electrodes (IDE) and reflectors on the surface of a 64° YX-LiNbO3 based piezoelectric substrate. A flow cell, with a reservoir volume of 3 μl, which employs inlet and outlet ports for the microfluidic chamber and polydimethylsiloxane (PDMS) based microfluidic channels, was also designed and fabricated using acrylic material. Phenol and naphtho[2,3-a]dipyrido[3,2-h:2'3'-f] phenazine-5,18-dione (QDPPZ) were employed as the sensing layers for mercury and nickel ions, respectively. The frequency based response of the SH-SAW sensor demonstrated picomolar level detection for mercury nitrate (Hg(NO3)2) and nickel nitrate (Ni(NO3)2).","PeriodicalId":57667,"journal":{"name":"时间频率公报","volume":"18 1","pages":"536-540"},"PeriodicalIF":0.0,"publicationDate":"2015-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87325994","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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