Pub Date : 2006-05-08DOI: 10.1109/MEMSYS.2006.1627848
E. J. van der Wouden, D. Liang, D. Hermes, J. Gardeniers, A. van den Berg
Electroosmotic flow (EOF) in a microchannel can be controlled electronically by use of an electrode embedded in the wall of the channel. By setting a voltage to the electrode, the zeta-potential at the wall can be changed locally. Thus, the electrode acts as a "gate" for liquid flow, in analogy with a gate in a field-effect transistor. This paper describes the control of EOF by the synchronized switching of the gate potential with the channel axial potential. The advantage of this procedure is that potential gas formation by electrolysis at the electrodes that provide the axial electric field is suppressed, while the direction and magnitude of the EOF can be maintained. The results show that the flow velocity is linearly dependent on the applied gate potential and varies with the phase difference between the applied gate and channel potential. An analysis of the time constants involved in the charging of the insulator, and therewith the switching of the zeta potential, is made in order to predict the maximum operating frequency.
{"title":"Field-effect control of electro-osmotic flow with synchronized AC-switching of channel and gate potentials","authors":"E. J. van der Wouden, D. Liang, D. Hermes, J. Gardeniers, A. van den Berg","doi":"10.1109/MEMSYS.2006.1627848","DOIUrl":"https://doi.org/10.1109/MEMSYS.2006.1627848","url":null,"abstract":"Electroosmotic flow (EOF) in a microchannel can be controlled electronically by use of an electrode embedded in the wall of the channel. By setting a voltage to the electrode, the zeta-potential at the wall can be changed locally. Thus, the electrode acts as a \"gate\" for liquid flow, in analogy with a gate in a field-effect transistor. This paper describes the control of EOF by the synchronized switching of the gate potential with the channel axial potential. The advantage of this procedure is that potential gas formation by electrolysis at the electrodes that provide the axial electric field is suppressed, while the direction and magnitude of the EOF can be maintained. The results show that the flow velocity is linearly dependent on the applied gate potential and varies with the phase difference between the applied gate and channel potential. An analysis of the time constants involved in the charging of the insulator, and therewith the switching of the zeta potential, is made in order to predict the maximum operating frequency.","PeriodicalId":250831,"journal":{"name":"19th IEEE International Conference on Micro Electro Mechanical Systems","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126713741","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 : 2006-05-08DOI: 10.1109/MEMSYS.2006.1627762
S. Haeberle, N. Schmitt, R. Zengerle, J. Ducrée
This paper describes a novel gas micropump on a centrifugal microfluidic platform. The pump is integrated on a passive and microstructured polymer disk which is sealed with an elastomer lid featuring paramagnetic inlays. The rotational motion of this hybrid disk over a stationary magnet induces a designated sequence of volume displacements of the elastic lid, leading to a net transport of gas. The pumping pressure scales linearly with the frequency, with a maximum observable pressure of 4.1 kPa. The first application of this rotary device is the production of gas-liquid flows by pumping ambient air into a continuous centrifugal flow of liquid. The injected gas volume segments the liquid stream into a series of liquid compartments. Apart from such multi-phase flows, the new pumping technique supplements a generic air-to-liquid sampling method to centrifugal microfluidic platforms.
{"title":"A Centrifugo-Magnetically Actuated Gas Micropump","authors":"S. Haeberle, N. Schmitt, R. Zengerle, J. Ducrée","doi":"10.1109/MEMSYS.2006.1627762","DOIUrl":"https://doi.org/10.1109/MEMSYS.2006.1627762","url":null,"abstract":"This paper describes a novel gas micropump on a centrifugal microfluidic platform. The pump is integrated on a passive and microstructured polymer disk which is sealed with an elastomer lid featuring paramagnetic inlays. The rotational motion of this hybrid disk over a stationary magnet induces a designated sequence of volume displacements of the elastic lid, leading to a net transport of gas. The pumping pressure scales linearly with the frequency, with a maximum observable pressure of 4.1 kPa. The first application of this rotary device is the production of gas-liquid flows by pumping ambient air into a continuous centrifugal flow of liquid. The injected gas volume segments the liquid stream into a series of liquid compartments. Apart from such multi-phase flows, the new pumping technique supplements a generic air-to-liquid sampling method to centrifugal microfluidic platforms.","PeriodicalId":250831,"journal":{"name":"19th IEEE International Conference on Micro Electro Mechanical Systems","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126845830","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 : 2006-05-08DOI: 10.1109/MEMSYS.2006.1627889
W. Sung, J.Y. Lee, J.G. Lee, T. Kang
In this paper, we present a new approach for performance enhancement of MEMS vibratory gyroscope by means of automatic mode control scheme. The suggested method automatically tunes resonant frequencies of two lateral modes to be identically matched. This draws sensitivity improvement of the sensor and removes manual tuning effort, which are desirable features to achieve a high performance for the mass productive sensor like vibratory gyroscopes. In this paper, we designed and fabricated an electrostatically tunable gyro structure of parallel-type sensing electrodes and automatic mode tuning circuit that utilizes a PLL-based two self-oscillation loops for both driving and sensing mode.
{"title":"Design And Fabrication of Anautomatic Mode Controlled Vibratory Gyroscope","authors":"W. Sung, J.Y. Lee, J.G. Lee, T. Kang","doi":"10.1109/MEMSYS.2006.1627889","DOIUrl":"https://doi.org/10.1109/MEMSYS.2006.1627889","url":null,"abstract":"In this paper, we present a new approach for performance enhancement of MEMS vibratory gyroscope by means of automatic mode control scheme. The suggested method automatically tunes resonant frequencies of two lateral modes to be identically matched. This draws sensitivity improvement of the sensor and removes manual tuning effort, which are desirable features to achieve a high performance for the mass productive sensor like vibratory gyroscopes. In this paper, we designed and fabricated an electrostatically tunable gyro structure of parallel-type sensing electrodes and automatic mode tuning circuit that utilizes a PLL-based two self-oscillation loops for both driving and sensing mode.","PeriodicalId":250831,"journal":{"name":"19th IEEE International Conference on Micro Electro Mechanical Systems","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123308399","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 : 2006-05-08DOI: 10.1109/MEMSYS.2006.1627810
X. Xiong, M. Gungormus, C. Tamerler, M. Sarikaya, B. Parviz
We present a controllable self-assembly method for guiding and positioning nano-scale objects onto a microfabricated template mediated by a genetically engineered polypeptide. Inspired by nature, our group has adapted the different molecular biology based protocols to identify and tailor polypeptides that can recognize and specifically bind to inorganic surfaces. In this paper, we show a three-repeat form of a cell surface selected gold binding polypeptide (GBP1:MHGKTQATSGTIQS). We delineate the procedures including how to identify the polypeptide; how to use this polypeptide for the bottom up self-assembly of semiconducting quantum dots (QDs) onto microfabricated patterns; and finally how to achieve a further level of control over the binding of the polypeptide to microstructures via application of a bias voltage. Our approach opens a new venue for bridging the biological and inorganic domains, and guiding self-assembly of structures and devices from the bottom up.
{"title":"Electronic Control of Binding of Genetically Engineered Polypeptides to Microfabricated Structures","authors":"X. Xiong, M. Gungormus, C. Tamerler, M. Sarikaya, B. Parviz","doi":"10.1109/MEMSYS.2006.1627810","DOIUrl":"https://doi.org/10.1109/MEMSYS.2006.1627810","url":null,"abstract":"We present a controllable self-assembly method for guiding and positioning nano-scale objects onto a microfabricated template mediated by a genetically engineered polypeptide. Inspired by nature, our group has adapted the different molecular biology based protocols to identify and tailor polypeptides that can recognize and specifically bind to inorganic surfaces. In this paper, we show a three-repeat form of a cell surface selected gold binding polypeptide (GBP1:MHGKTQATSGTIQS). We delineate the procedures including how to identify the polypeptide; how to use this polypeptide for the bottom up self-assembly of semiconducting quantum dots (QDs) onto microfabricated patterns; and finally how to achieve a further level of control over the binding of the polypeptide to microstructures via application of a bias voltage. Our approach opens a new venue for bridging the biological and inorganic domains, and guiding self-assembly of structures and devices from the bottom up.","PeriodicalId":250831,"journal":{"name":"19th IEEE International Conference on Micro Electro Mechanical Systems","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123464183","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 : 2006-05-08DOI: 10.1109/MEMSYS.2006.1627895
C. Peng, Xianxiang Chen, Q. Bai, L. Luo, S. Xia
This paper reports a high performance micromechanical resonant electrostatic field sensor (EFS) that is fabricated with a three-layer polysilicon surface micromachining process. The EFS has a high resolution of 100V/m when used in ambient air at room temperature. The driving voltage is 25V DC and 0.3Vp-p AC lower than other reported electrostatic comb driven devices. Experimental results show that the EFS can be succeeded in atmospheric electric field detecting.
{"title":"A Novel High Performance Micromechanical Resonant Electrostatic Field Sensor Used In Atmospheric Electric Field Detection","authors":"C. Peng, Xianxiang Chen, Q. Bai, L. Luo, S. Xia","doi":"10.1109/MEMSYS.2006.1627895","DOIUrl":"https://doi.org/10.1109/MEMSYS.2006.1627895","url":null,"abstract":"This paper reports a high performance micromechanical resonant electrostatic field sensor (EFS) that is fabricated with a three-layer polysilicon surface micromachining process. The EFS has a high resolution of 100V/m when used in ambient air at room temperature. The driving voltage is 25V DC and 0.3Vp-p AC lower than other reported electrostatic comb driven devices. Experimental results show that the EFS can be succeeded in atmospheric electric field detecting.","PeriodicalId":250831,"journal":{"name":"19th IEEE International Conference on Micro Electro Mechanical Systems","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121342449","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 : 2006-05-08DOI: 10.1109/MEMSYS.2006.1627805
M. Rabold, A. Doll, F. Goldschmidtboing, P. Woias
This paper presents a novel test method for a non-destructive strength characterization of bonded silicon wafer pairs. The test is based on a controlled crack generation at the bond interface using a modified blister test method. An analytical model was used to establish an essential design parameter. Therewith, different test structures were analyzed and important information about crack generation and crack propagation were gained. Finally, the theory of controlled crack generation was verified and demonstrated by a modified blister test.
{"title":"Non-Destructive Strength Characterization of Full-Wafer Bonds Using a Modified Blister Test Method","authors":"M. Rabold, A. Doll, F. Goldschmidtboing, P. Woias","doi":"10.1109/MEMSYS.2006.1627805","DOIUrl":"https://doi.org/10.1109/MEMSYS.2006.1627805","url":null,"abstract":"This paper presents a novel test method for a non-destructive strength characterization of bonded silicon wafer pairs. The test is based on a controlled crack generation at the bond interface using a modified blister test method. An analytical model was used to establish an essential design parameter. Therewith, different test structures were analyzed and important information about crack generation and crack propagation were gained. Finally, the theory of controlled crack generation was verified and demonstrated by a modified blister test.","PeriodicalId":250831,"journal":{"name":"19th IEEE International Conference on Micro Electro Mechanical Systems","volume":"177 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121432502","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 : 2006-05-08DOI: 10.1109/MEMSYS.2006.1627828
Kuo‐Hoong Lee, Y. Su, Shean-Jen Chen, Gwo-Bin Lee
This paper reports a novel microfluidic chip integrated with arrayed molecular imprinting polymer (MIP) films for surface plasmon resonance (SPR) phase imaging of specific bio-samples. The SPR imaging system uses a surface-sensitive optical technique to detect two-dimensional spatial phase variation caused by bio-molecules absorbed on a sensing surface composed of highly-specific MIP films. The developed system has a high resolution and a high-throughput screening capability and has been successfully applied to the analysis of multiple bio-molecules without the need for additional labeling in long-term measuring. The innovative microfluidic chip is capable of transporting a specific amount of multiple bio-samples inside multiple microchannels using micropumps/microvalves to the sensing regions where arrayed MIP films are locally deposited such that highly-sensitive, highly-specific bio-sensing can be achieved.
{"title":"2-Dimensional SPR Detection System Integrated with Molecular Imprinting Polymer Microarrays Using Microfluidic Technology","authors":"Kuo‐Hoong Lee, Y. Su, Shean-Jen Chen, Gwo-Bin Lee","doi":"10.1109/MEMSYS.2006.1627828","DOIUrl":"https://doi.org/10.1109/MEMSYS.2006.1627828","url":null,"abstract":"This paper reports a novel microfluidic chip integrated with arrayed molecular imprinting polymer (MIP) films for surface plasmon resonance (SPR) phase imaging of specific bio-samples. The SPR imaging system uses a surface-sensitive optical technique to detect two-dimensional spatial phase variation caused by bio-molecules absorbed on a sensing surface composed of highly-specific MIP films. The developed system has a high resolution and a high-throughput screening capability and has been successfully applied to the analysis of multiple bio-molecules without the need for additional labeling in long-term measuring. The innovative microfluidic chip is capable of transporting a specific amount of multiple bio-samples inside multiple microchannels using micropumps/microvalves to the sensing regions where arrayed MIP films are locally deposited such that highly-sensitive, highly-specific bio-sensing can be achieved.","PeriodicalId":250831,"journal":{"name":"19th IEEE International Conference on Micro Electro Mechanical Systems","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122336914","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 : 2006-05-08DOI: 10.1109/MEMSYS.2006.1627759
M. Agarwal, K.K. Park, M. Hopcroft, S. Chandorkar, R. Candler, B. Kim, R. Melamud, G. Yama, B. Murmann, T. Kenny
Micromechanical Resonator based oscillators are a promising technology for replacing quartz crystal based oscillators. In this work, we will report the effects of mechanical vibrations and bias voltage noise on the phase noise performance of electrostatic MEMS resonator based oscillators. Accurate models for both these effects are discussed along with their experimental verification using a 1.3MHz, epi-silicon encapsulated Single Anchored Double Ended Tuning Fork (DETF) resonator. The acceleration sensitivity of the resonator was found to be < 10ppb/g which is better than many low cost crystal resonators, and shows potential for improvement to get performance which is at par or better than quartz crystal oscillators.
{"title":"Effects of Mechanical Vibrations and Bias Voltage Noise on Phase Noise of MEMS Resonator Based Oscillators","authors":"M. Agarwal, K.K. Park, M. Hopcroft, S. Chandorkar, R. Candler, B. Kim, R. Melamud, G. Yama, B. Murmann, T. Kenny","doi":"10.1109/MEMSYS.2006.1627759","DOIUrl":"https://doi.org/10.1109/MEMSYS.2006.1627759","url":null,"abstract":"Micromechanical Resonator based oscillators are a promising technology for replacing quartz crystal based oscillators. In this work, we will report the effects of mechanical vibrations and bias voltage noise on the phase noise performance of electrostatic MEMS resonator based oscillators. Accurate models for both these effects are discussed along with their experimental verification using a 1.3MHz, epi-silicon encapsulated Single Anchored Double Ended Tuning Fork (DETF) resonator. The acceleration sensitivity of the resonator was found to be < 10ppb/g which is better than many low cost crystal resonators, and shows potential for improvement to get performance which is at par or better than quartz crystal oscillators.","PeriodicalId":250831,"journal":{"name":"19th IEEE International Conference on Micro Electro Mechanical Systems","volume":"204 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121243349","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 : 2006-05-08DOI: 10.1109/MEMSYS.2006.1627949
Y. Takei, K. Hoshino, K. Matsumoto, I. Shimoyama
We have achieved the density control of carbon nanotubes (CNTs) by changing ethanol vapor flow speed in chemical vapor deposition (CVD). We calculated the ethanol mean free path under the CVD condition. From the calculation we estimated the minimum width of the flow channel that ethanol molecules can act as continuum. We fabricated the flow channels on a silicon wafer where ethanol vapor runs with its speed changing. Holes which CNTs can bridge were fabricated at the bottom of the flow channels. After the CVD process, we observed CNTs bridging the holes with scanning electron microscope (SEM). As a result, we observed that density of the synthesized CNTs, in other words, total length of the CNTs bridging the holes, increased with increasing the ethanol vapor flow speed.
{"title":"Density Control of Carbon Nanotubes Using Ethanol Vapor Flow","authors":"Y. Takei, K. Hoshino, K. Matsumoto, I. Shimoyama","doi":"10.1109/MEMSYS.2006.1627949","DOIUrl":"https://doi.org/10.1109/MEMSYS.2006.1627949","url":null,"abstract":"We have achieved the density control of carbon nanotubes (CNTs) by changing ethanol vapor flow speed in chemical vapor deposition (CVD). We calculated the ethanol mean free path under the CVD condition. From the calculation we estimated the minimum width of the flow channel that ethanol molecules can act as continuum. We fabricated the flow channels on a silicon wafer where ethanol vapor runs with its speed changing. Holes which CNTs can bridge were fabricated at the bottom of the flow channels. After the CVD process, we observed CNTs bridging the holes with scanning electron microscope (SEM). As a result, we observed that density of the synthesized CNTs, in other words, total length of the CNTs bridging the holes, increased with increasing the ethanol vapor flow speed.","PeriodicalId":250831,"journal":{"name":"19th IEEE International Conference on Micro Electro Mechanical Systems","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114301427","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 : 2006-05-08DOI: 10.1109/MEMSYS.2006.1627761
J. Oberhammer, G. Stemme
Firstly, this paper discusses why the “ conventional”, most-commonly used electrostatic switch concept based on a deflected cantilever is not very suitable for soft metal contact materials, since it creates only a weak release force not sufficient for overcoming the adhesion force between soft metal contacts, and its contact force is typically stronger than necessary for soft contact materials. Secondly, this paper presents a mechanically bi-stable, electrostatically actuated switch concept with a large active opening force and a small passive closing force, adapted to the contact and adhesion force requirements of soft contact materials such as gold. The theoretical discussion of the two concepts is supported by simulation results, by measurements of fabricated devices, and by an analysis of switches published in the literature.
{"title":"Passive Contact Force and Active Opening Force Electrostatic Switches for Soft Metal Contact Materials","authors":"J. Oberhammer, G. Stemme","doi":"10.1109/MEMSYS.2006.1627761","DOIUrl":"https://doi.org/10.1109/MEMSYS.2006.1627761","url":null,"abstract":"Firstly, this paper discusses why the “ conventional”, most-commonly used electrostatic switch concept based on a deflected cantilever is not very suitable for soft metal contact materials, since it creates only a weak release force not sufficient for overcoming the adhesion force between soft metal contacts, and its contact force is typically stronger than necessary for soft contact materials. Secondly, this paper presents a mechanically bi-stable, electrostatically actuated switch concept with a large active opening force and a small passive closing force, adapted to the contact and adhesion force requirements of soft contact materials such as gold. The theoretical discussion of the two concepts is supported by simulation results, by measurements of fabricated devices, and by an analysis of switches published in the literature.","PeriodicalId":250831,"journal":{"name":"19th IEEE International Conference on Micro Electro Mechanical Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131395280","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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