Pub Date : 2009-03-27DOI: 10.1109/MEMSYS.2009.4805322
Q. Zhou, L. Lin
The conventional chemical vapor deposition system has been miniaturized to the micro scale, leading to several potential advantages for the synthesis of nanostructures. First, minute heat capacity leads to fast temperature stabilization. Second, tiny chamber volume helps for rapid gas species exchanges. Third, small Reynolds number ensures laminar flow for better control of deposition sources. Forth, small diffusion length near the chemical reaction surface enhances efficient gas mass transfer. As a demonstration of principle, high-quality single-walled carbon nanotubes (SWNTs) are synthesized while similar experimental parameters in a large scale system fail to construct good quality SWNTs.
{"title":"Micro Chemical Vapor Deposition System: Design and Verification","authors":"Q. Zhou, L. Lin","doi":"10.1109/MEMSYS.2009.4805322","DOIUrl":"https://doi.org/10.1109/MEMSYS.2009.4805322","url":null,"abstract":"The conventional chemical vapor deposition system has been miniaturized to the micro scale, leading to several potential advantages for the synthesis of nanostructures. First, minute heat capacity leads to fast temperature stabilization. Second, tiny chamber volume helps for rapid gas species exchanges. Third, small Reynolds number ensures laminar flow for better control of deposition sources. Forth, small diffusion length near the chemical reaction surface enhances efficient gas mass transfer. As a demonstration of principle, high-quality single-walled carbon nanotubes (SWNTs) are synthesized while similar experimental parameters in a large scale system fail to construct good quality SWNTs.","PeriodicalId":187850,"journal":{"name":"2009 IEEE 22nd International Conference on Micro Electro Mechanical Systems","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116200057","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 : 2009-03-27DOI: 10.1109/MEMSYS.2009.4805553
R. K. Dhull, I. Puchades, L. Fuller, Y. W. Lu
This paper presents a simple means that utilizes surface tension gradient to cause droplet deformation, and to tilt micro-objects. Thermocapillary or Marangoni effect, and contact angle hysteresis are employed to control the droplet shape and position. The device consists of a microplate placed onto a microdroplet, and can produce a 6.5° tilting angle when actuated at 30 V. It shows the potential applications in scanning micromirror and display technology.
{"title":"Optical Micromirror Actuation using Thermocapillary Effect in Microdroplets","authors":"R. K. Dhull, I. Puchades, L. Fuller, Y. W. Lu","doi":"10.1109/MEMSYS.2009.4805553","DOIUrl":"https://doi.org/10.1109/MEMSYS.2009.4805553","url":null,"abstract":"This paper presents a simple means that utilizes surface tension gradient to cause droplet deformation, and to tilt micro-objects. Thermocapillary or Marangoni effect, and contact angle hysteresis are employed to control the droplet shape and position. The device consists of a microplate placed onto a microdroplet, and can produce a 6.5° tilting angle when actuated at 30 V. It shows the potential applications in scanning micromirror and display technology.","PeriodicalId":187850,"journal":{"name":"2009 IEEE 22nd International Conference on Micro Electro Mechanical Systems","volume":"159 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114423895","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 : 2009-03-27DOI: 10.1109/MEMSYS.2009.4805316
F. Arai, S. Sakuma, Yoko Yamanishi, K. Onda
We succeeded in powerful noncontact actuation of magnetically driven microtool (MMT) by magnetizing it and focusing magnetic field in a microfluidic chip. Novelty of this paper is summarized as follows. (1) We employed neodium powder as the main component of MMT. The density of magnetic flux was improved about 100 times larger after magnetization. (2) We fabricated a pair of magnetic sharp needles in the chip by electroplating. MMT was placed between the needles and the density of magnetic flux was improved about 3 times larger. As a result, we succeeded in powerful actuation of MMT in the chip. Drive frequency was improved about 10 times faster (up to 180Hz).
{"title":"Powerful Actuation of Magnetized Microtool by Focused Magnetic Field on a Disposable Microfluidic Chip","authors":"F. Arai, S. Sakuma, Yoko Yamanishi, K. Onda","doi":"10.1109/MEMSYS.2009.4805316","DOIUrl":"https://doi.org/10.1109/MEMSYS.2009.4805316","url":null,"abstract":"We succeeded in powerful noncontact actuation of magnetically driven microtool (MMT) by magnetizing it and focusing magnetic field in a microfluidic chip. Novelty of this paper is summarized as follows. (1) We employed neodium powder as the main component of MMT. The density of magnetic flux was improved about 100 times larger after magnetization. (2) We fabricated a pair of magnetic sharp needles in the chip by electroplating. MMT was placed between the needles and the density of magnetic flux was improved about 3 times larger. As a result, we succeeded in powerful actuation of MMT in the chip. Drive frequency was improved about 10 times faster (up to 180Hz).","PeriodicalId":187850,"journal":{"name":"2009 IEEE 22nd International Conference on Micro Electro Mechanical Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127288678","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 : 2009-03-27DOI: 10.1109/MEMSYS.2009.4805569
M. Edamoto, Y. Suzuki, N. Kasagi, K. Kashiwagi, Y. Morizawa, T. Yokoyama, T. Seki, M. Oba
A vibration-driven electret generator has been developed for energy harvesting applications. By using parylene as the spring material, a low-resonant-frequency MEMS generator is realized. Electrostatic levitation is adopted for the gap control. Large in-plane amplitude of 0.5 mm at the resonant frequency as low as 21 Hz has been achieved. We also demonstrate electret-powered operation of LED using a low-power-consumption impedance conversion circuit.
{"title":"Low-Resonant-Frequency Micro Electret Generator for Energy Harvesting Application","authors":"M. Edamoto, Y. Suzuki, N. Kasagi, K. Kashiwagi, Y. Morizawa, T. Yokoyama, T. Seki, M. Oba","doi":"10.1109/MEMSYS.2009.4805569","DOIUrl":"https://doi.org/10.1109/MEMSYS.2009.4805569","url":null,"abstract":"A vibration-driven electret generator has been developed for energy harvesting applications. By using parylene as the spring material, a low-resonant-frequency MEMS generator is realized. Electrostatic levitation is adopted for the gap control. Large in-plane amplitude of 0.5 mm at the resonant frequency as low as 21 Hz has been achieved. We also demonstrate electret-powered operation of LED using a low-power-consumption impedance conversion circuit.","PeriodicalId":187850,"journal":{"name":"2009 IEEE 22nd International Conference on Micro Electro Mechanical Systems","volume":"72 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123526361","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 : 2009-03-27DOI: 10.1109/MEMSYS.2009.4805562
C. Shao, Y. Kawai, T. Ono, M. Esashi
A time-of-flight scanning force microscope (SFM) probe with an ability to switch the measurement mode using the electrostatically switching mechanism is designed, fabricated and demonstrated the performance of it. In order to achieve surface observation and chemical analysis simultaneously for imaging the chemical property of a material surface, this probe can switch the positions of the cantilever between SFM mode and time-of-flight mass analysis (TOF-MA) mode by integrating a couple of electrostatic actuator with curved electrode. This mechanism will be applied to pick up an atom or molecule under SFM mode, then emits them to TOF mass analyzer using field evaporation for analyzing its mass in TOF-MA mode. To switch the cantilever position at TOF-MA mode, the fabricated probe generated the 255¿m of maximum displacement at the end of cantilever at an actuation voltage of 180V. The cantilever is attracted with the electrode according to the curved shape using electrostatically pull-in effect. The front edge of the cantilever was aligned in front of integrated extraction electrode for emitting chemical species. In SFM mode, the cantilever was also attracted to another electrode. The fundamental resonant frequency of the cantilever is increased from 1.8kHz to 6.8kHz before and after actuation. A calculated spring constant is changed from 0.05N/m to 0.34N/m.
{"title":"Mass-Analysis Scanning Force Microscopy with Electrostatic Switching Mechanism","authors":"C. Shao, Y. Kawai, T. Ono, M. Esashi","doi":"10.1109/MEMSYS.2009.4805562","DOIUrl":"https://doi.org/10.1109/MEMSYS.2009.4805562","url":null,"abstract":"A time-of-flight scanning force microscope (SFM) probe with an ability to switch the measurement mode using the electrostatically switching mechanism is designed, fabricated and demonstrated the performance of it. In order to achieve surface observation and chemical analysis simultaneously for imaging the chemical property of a material surface, this probe can switch the positions of the cantilever between SFM mode and time-of-flight mass analysis (TOF-MA) mode by integrating a couple of electrostatic actuator with curved electrode. This mechanism will be applied to pick up an atom or molecule under SFM mode, then emits them to TOF mass analyzer using field evaporation for analyzing its mass in TOF-MA mode. To switch the cantilever position at TOF-MA mode, the fabricated probe generated the 255¿m of maximum displacement at the end of cantilever at an actuation voltage of 180V. The cantilever is attracted with the electrode according to the curved shape using electrostatically pull-in effect. The front edge of the cantilever was aligned in front of integrated extraction electrode for emitting chemical species. In SFM mode, the cantilever was also attracted to another electrode. The fundamental resonant frequency of the cantilever is increased from 1.8kHz to 6.8kHz before and after actuation. A calculated spring constant is changed from 0.05N/m to 0.34N/m.","PeriodicalId":187850,"journal":{"name":"2009 IEEE 22nd International Conference on Micro Electro Mechanical Systems","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123539301","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 : 2009-03-27DOI: 10.1109/MEMSYS.2009.4805574
E. Sarajlic, C. Yamahata, M. Cordero, H. Fujita
Circular data tracks in present-day hard disk drives (HDD) are accessed by a read/write head mounted on a support arm, which is swung by a voice coil drive. The orientation of the head relative to a data track varies with the radial position of the track, causing an increase in data track misregistration and limiting the performance of HDD. We present a rotary micromotor which can be used as a secondary stage actuator to maintain a constant orientation between the head and the tracks during disk operation. This electrostatic stepper micromotor, bulk micromachined in a standard monocrystalline silicon wafer, uses flexure pivots to avoid any frictional contact of the rotor, providing precise, repeatable and reliable bidirectional stepping motion without feedback control. The experimental characterization of a prototype having a diameter of 1.4 mm has demonstrated a rotational range of 26° (+/- 13°) at 75 V, a resolution of 1/6° in a coarse stepping mode and a maximum speed of 1.67°/ms.
{"title":"Electrostatic Rotary Stepper Micromotor for Skew Angle Compensation in Hard Disk Drive","authors":"E. Sarajlic, C. Yamahata, M. Cordero, H. Fujita","doi":"10.1109/MEMSYS.2009.4805574","DOIUrl":"https://doi.org/10.1109/MEMSYS.2009.4805574","url":null,"abstract":"Circular data tracks in present-day hard disk drives (HDD) are accessed by a read/write head mounted on a support arm, which is swung by a voice coil drive. The orientation of the head relative to a data track varies with the radial position of the track, causing an increase in data track misregistration and limiting the performance of HDD. We present a rotary micromotor which can be used as a secondary stage actuator to maintain a constant orientation between the head and the tracks during disk operation. This electrostatic stepper micromotor, bulk micromachined in a standard monocrystalline silicon wafer, uses flexure pivots to avoid any frictional contact of the rotor, providing precise, repeatable and reliable bidirectional stepping motion without feedback control. The experimental characterization of a prototype having a diameter of 1.4 mm has demonstrated a rotational range of 26° (+/- 13°) at 75 V, a resolution of 1/6° in a coarse stepping mode and a maximum speed of 1.67°/ms.","PeriodicalId":187850,"journal":{"name":"2009 IEEE 22nd International Conference on Micro Electro Mechanical Systems","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121618524","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 : 2009-03-27DOI: 10.1109/MEMSYS.2009.4805459
Z. Wang, P. Fiorini, C. van Hoof
This paper reports the design, modeling, fabrication and measurement of a CMOS-compatible surface-micromachined test structure for the determination of the thermal conductivity of thin films based on the Seebeck effect. The Seebeck effect-based temperature sensing is more advantageous for thin film materials with a relatively large Seebeck coefficient, such as lightly doped poly-Si and poly-SiGe. In this paper, the conceptual design is first analyzed and then verified with finite element modeling. The test structure is fabricated with poly-Si70% Ge30%. Its functionality is demonstrated from experimental results. The sources of the measurement error are discussed and the solutions to minimize the measurement error are proposed.
{"title":"CMOS-Compatible Surface-Micromachined Test Structure for Determination of Thermal Conductivity of Thin Film Materials based on Seebeck Effect","authors":"Z. Wang, P. Fiorini, C. van Hoof","doi":"10.1109/MEMSYS.2009.4805459","DOIUrl":"https://doi.org/10.1109/MEMSYS.2009.4805459","url":null,"abstract":"This paper reports the design, modeling, fabrication and measurement of a CMOS-compatible surface-micromachined test structure for the determination of the thermal conductivity of thin films based on the Seebeck effect. The Seebeck effect-based temperature sensing is more advantageous for thin film materials with a relatively large Seebeck coefficient, such as lightly doped poly-Si and poly-SiGe. In this paper, the conceptual design is first analyzed and then verified with finite element modeling. The test structure is fabricated with poly-Si70% Ge30%. Its functionality is demonstrated from experimental results. The sources of the measurement error are discussed and the solutions to minimize the measurement error are proposed.","PeriodicalId":187850,"journal":{"name":"2009 IEEE 22nd International Conference on Micro Electro Mechanical Systems","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121923929","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 : 2009-03-27DOI: 10.1109/MEMSYS.2009.4805388
K. Lien, Chien-Ju Liu, P. Kuo, Gwo-Bin Lee
This study presents a new magnetic bead-based microfluidic platform for genomic DNA (gDNA) extraction and rapid detection of genetic deletion from saliva samples by using micro-electro-mechanical-systems (MEMS)-based technologies. With the incorporation of several microfluidic devices, a charge-switchable, magnetic bead was used to extract gDNA released from the buccal cells in the saliva samples and collected by a built-in microcoils array. A new normally-closed micropump for liquid delivery and a new self-compensated micro temperature control module for on-chip PCR were all integrated into a single chip. Successful demonstration for detection of the patients with genetic deletion has been achieved by using the proposed microfluidic platform. Consequently, the integrated miniature saliva-based microfluidic system can provide a promising platform for rapid DNA extraction and fast detection of genetic diseases in a shorter period of time automatically.
{"title":"Bead-Based Microfluidic Platform Integrated with Optical Detection Devices for Rapid Detection of Genetic Deletion from Saliva","authors":"K. Lien, Chien-Ju Liu, P. Kuo, Gwo-Bin Lee","doi":"10.1109/MEMSYS.2009.4805388","DOIUrl":"https://doi.org/10.1109/MEMSYS.2009.4805388","url":null,"abstract":"This study presents a new magnetic bead-based microfluidic platform for genomic DNA (gDNA) extraction and rapid detection of genetic deletion from saliva samples by using micro-electro-mechanical-systems (MEMS)-based technologies. With the incorporation of several microfluidic devices, a charge-switchable, magnetic bead was used to extract gDNA released from the buccal cells in the saliva samples and collected by a built-in microcoils array. A new normally-closed micropump for liquid delivery and a new self-compensated micro temperature control module for on-chip PCR were all integrated into a single chip. Successful demonstration for detection of the patients with genetic deletion has been achieved by using the proposed microfluidic platform. Consequently, the integrated miniature saliva-based microfluidic system can provide a promising platform for rapid DNA extraction and fast detection of genetic diseases in a shorter period of time automatically.","PeriodicalId":187850,"journal":{"name":"2009 IEEE 22nd International Conference on Micro Electro Mechanical Systems","volume":"247 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123390198","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 : 2009-03-27DOI: 10.1109/MEMSYS.2009.4805445
Shoichi Akiyama, Y. T. Cheng, J. Fattaccioli, N. Takama, Peter Löw, C. Bergaud, Beomjoon Kim
In this paper we present the results of surface temperature control of silicon nanowires by using fluorescent thermometry at the nanometer scale. Rhodamine B is one of the stable fluorescent molecules, which rely on the characteristic of temperature-dependent change in fluorescent intensity, and it was used for nano-scale surface temperature sensing interface. The resistive heating on Si nanowires was carried out with applying voltage potential of 6 ~ 12 V. Surface-temperature measurement was performed by converting the changes in fluorescent intensity with calibration curve of Rhodamine B. The temperature at the central line along nanowires increasing from 30 degrees to 35~70 degrees was observed.
{"title":"Surface-Temperature Control of Silicon Nanowires in Dry and Liquid Conditions","authors":"Shoichi Akiyama, Y. T. Cheng, J. Fattaccioli, N. Takama, Peter Löw, C. Bergaud, Beomjoon Kim","doi":"10.1109/MEMSYS.2009.4805445","DOIUrl":"https://doi.org/10.1109/MEMSYS.2009.4805445","url":null,"abstract":"In this paper we present the results of surface temperature control of silicon nanowires by using fluorescent thermometry at the nanometer scale. Rhodamine B is one of the stable fluorescent molecules, which rely on the characteristic of temperature-dependent change in fluorescent intensity, and it was used for nano-scale surface temperature sensing interface. The resistive heating on Si nanowires was carried out with applying voltage potential of 6 ~ 12 V. Surface-temperature measurement was performed by converting the changes in fluorescent intensity with calibration curve of Rhodamine B. The temperature at the central line along nanowires increasing from 30 degrees to 35~70 degrees was observed.","PeriodicalId":187850,"journal":{"name":"2009 IEEE 22nd International Conference on Micro Electro Mechanical Systems","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123560802","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 : 2009-03-27DOI: 10.1109/MEMSYS.2009.4805350
S.-J. Park, B. Petzold, M. Goodman, B. Pruitt
Understanding how the mechanoreceptor neurons of Caenorhabditis elegans mediate mechanotransduction can unravel how touch works, but new tools are required to quantitatively analyze the relationship between mechanical loading and the physiological response. Here we present a piezoresistive cantilever-based force clamp system that can apply user-defined force profiles to C. elegans. We present a novel MEMS force-clamp system and demonstrate a piezoresistive cantilever with low 1/f noise, low noise floor and high force resolution suitable for these measurements. Initial studies enabled by the system are also discussed.
{"title":"Piezoresistive Cantilever-based Force-Clamp System for the Study of Mechanotransduction in C. Elegans","authors":"S.-J. Park, B. Petzold, M. Goodman, B. Pruitt","doi":"10.1109/MEMSYS.2009.4805350","DOIUrl":"https://doi.org/10.1109/MEMSYS.2009.4805350","url":null,"abstract":"Understanding how the mechanoreceptor neurons of Caenorhabditis elegans mediate mechanotransduction can unravel how touch works, but new tools are required to quantitatively analyze the relationship between mechanical loading and the physiological response. Here we present a piezoresistive cantilever-based force clamp system that can apply user-defined force profiles to C. elegans. We present a novel MEMS force-clamp system and demonstrate a piezoresistive cantilever with low 1/f noise, low noise floor and high force resolution suitable for these measurements. Initial studies enabled by the system are also discussed.","PeriodicalId":187850,"journal":{"name":"2009 IEEE 22nd International Conference on Micro Electro Mechanical Systems","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128297672","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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