Pub Date : 2013-08-01DOI: 10.1109/3M-NANO.2013.6737382
Yu Hou, Zuobin Wang, Jiaojiao Song, Dayou Li, Y. Yue, C. Maple
This paper presents a method to make magnetic surface patterns by non-destructive laser interference, and periodic magnetic fringes produced on magnetic material surfaces are investigated by magnetic force microscopy (MFM). Various thermal effects are obtained by two beam laser interference with different exposure times and pulse energies. The experimental results have shown that magnetic patterns can be made on magnetic materials by laser interference without any damage to the surfaces. The method provides a way for the rapid producing of magnetic marks or recording magnetic data in a large area on a magnetic material surface, and it could be useful for biological, material, optical, electronic and information engineering applications.
{"title":"Magnetic surface patterns made by non-destructive laser interference","authors":"Yu Hou, Zuobin Wang, Jiaojiao Song, Dayou Li, Y. Yue, C. Maple","doi":"10.1109/3M-NANO.2013.6737382","DOIUrl":"https://doi.org/10.1109/3M-NANO.2013.6737382","url":null,"abstract":"This paper presents a method to make magnetic surface patterns by non-destructive laser interference, and periodic magnetic fringes produced on magnetic material surfaces are investigated by magnetic force microscopy (MFM). Various thermal effects are obtained by two beam laser interference with different exposure times and pulse energies. The experimental results have shown that magnetic patterns can be made on magnetic materials by laser interference without any damage to the surfaces. The method provides a way for the rapid producing of magnetic marks or recording magnetic data in a large area on a magnetic material surface, and it could be useful for biological, material, optical, electronic and information engineering applications.","PeriodicalId":120368,"journal":{"name":"2013 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale","volume":"208 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122771767","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 : 2013-08-01DOI: 10.1109/3M-NANO.2013.6737380
F. Zhang, X. Zhang, L. Yuan, W. Zhang, D. Huo, Y. Y. Wang, C. Peng
Superhydrophobic and self-cleaning are the key properties of some species of plant leaves due to the micro-and nano-structures on the surface. In this paper, Berberis thunbergii leaves with nano-hairy and micro-trichomes structures, was used as template for replication. The negative replica was fabricated by casting PDMS on the template, and then positive replica was fabricated by casting UV-photoresist on the PDMS replica. Contact angle of 141° was achieved with the positive replica.
{"title":"Superhydrophobic micro-nano structures transferred from Berberis thunbergii leaves","authors":"F. Zhang, X. Zhang, L. Yuan, W. Zhang, D. Huo, Y. Y. Wang, C. Peng","doi":"10.1109/3M-NANO.2013.6737380","DOIUrl":"https://doi.org/10.1109/3M-NANO.2013.6737380","url":null,"abstract":"Superhydrophobic and self-cleaning are the key properties of some species of plant leaves due to the micro-and nano-structures on the surface. In this paper, Berberis thunbergii leaves with nano-hairy and micro-trichomes structures, was used as template for replication. The negative replica was fabricated by casting PDMS on the template, and then positive replica was fabricated by casting UV-photoresist on the PDMS replica. Contact angle of 141° was achieved with the positive replica.","PeriodicalId":120368,"journal":{"name":"2013 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale","volume":"356 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122162041","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 : 2013-08-01DOI: 10.1109/3M-NANO.2013.6737384
Jing Li, Jinkai Xu, Feng Du, Chengyu Xu, Huadong Yu
The phenomena that biological functions originate from biological coupling are the important biological foundation of multiple bionics and the significant discoveries in the bionic fields. In this paper, the multiple coupling characteristics and the superhydrophobic properties of the upper surface of the lotus leaf and artificial biomimetic surfaces were investigated through laser scanning confocal microscope, scanning electron microscopy and contact angle measurement. The results indicate that the multiple factors including morphology and/or microstructure and materials coupling by certain coupling mechanisms may carry out to produce superhydrophobic surfaces. By learning from and mimicking what was found, more bionic surfaces with similar properties can be created and find their applications where superhydrophobicity is required.
{"title":"Superhydrophobic properties of multiple coupling","authors":"Jing Li, Jinkai Xu, Feng Du, Chengyu Xu, Huadong Yu","doi":"10.1109/3M-NANO.2013.6737384","DOIUrl":"https://doi.org/10.1109/3M-NANO.2013.6737384","url":null,"abstract":"The phenomena that biological functions originate from biological coupling are the important biological foundation of multiple bionics and the significant discoveries in the bionic fields. In this paper, the multiple coupling characteristics and the superhydrophobic properties of the upper surface of the lotus leaf and artificial biomimetic surfaces were investigated through laser scanning confocal microscope, scanning electron microscopy and contact angle measurement. The results indicate that the multiple factors including morphology and/or microstructure and materials coupling by certain coupling mechanisms may carry out to produce superhydrophobic surfaces. By learning from and mimicking what was found, more bionic surfaces with similar properties can be created and find their applications where superhydrophobicity is required.","PeriodicalId":120368,"journal":{"name":"2013 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129296193","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 : 2013-08-01DOI: 10.1109/3M-NANO.2013.6737428
Qili Zhao, Mingzhu Sun, Maosheng Cui, Jin Yu, Xin Zhao
Cell weighing has great potential applications in probing the cellular composition and quantifying material interaction of the cell. In this paper, a novel and simple robotic weighing approach for spherical cells is proposed to avoid high cost of involved devices in traditional methods. According physical knowledge, the spherical cells released in enormous liquid environment tends to fall at a constant speed. The density of cell can be estimated from this constant speed, and in consequence, the mass of cell can be derived. Based on this point, the constant falling speed detection process is realized robotically on a traditional micro-operation system in this paper. Experimental results demonstrate that the detected density of sheep oocyte is accordance with the known water-percentage of biological cells, which proves the feasibility of the proposed weighing method. Furthermore, the proposed approach is proved to detect the tiny mass-variation of the cell (less than 2%), which proves the high sensitivity of our method.
{"title":"Robotic weighing for spherical cells based on falling speed detection","authors":"Qili Zhao, Mingzhu Sun, Maosheng Cui, Jin Yu, Xin Zhao","doi":"10.1109/3M-NANO.2013.6737428","DOIUrl":"https://doi.org/10.1109/3M-NANO.2013.6737428","url":null,"abstract":"Cell weighing has great potential applications in probing the cellular composition and quantifying material interaction of the cell. In this paper, a novel and simple robotic weighing approach for spherical cells is proposed to avoid high cost of involved devices in traditional methods. According physical knowledge, the spherical cells released in enormous liquid environment tends to fall at a constant speed. The density of cell can be estimated from this constant speed, and in consequence, the mass of cell can be derived. Based on this point, the constant falling speed detection process is realized robotically on a traditional micro-operation system in this paper. Experimental results demonstrate that the detected density of sheep oocyte is accordance with the known water-percentage of biological cells, which proves the feasibility of the proposed weighing method. Furthermore, the proposed approach is proved to detect the tiny mass-variation of the cell (less than 2%), which proves the high sensitivity of our method.","PeriodicalId":120368,"journal":{"name":"2013 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale","volume":"302 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124304721","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 : 2013-08-01DOI: 10.1109/3M-NANO.2013.6737452
C. Rong, X. Gu, W.P. Liu, W. Zhang, F. Zhang, L. Yuan, Y. Y. Wang, C. Peng
Periodic pyramid and random nanostructure binary structures of single-crystal silicon wafer was fabricated by chemical etching method. Much lower reflectance of silicon wafer with these structures was obtained compared with that of single pyramid arrays. The morphology and reflectivity of these structures, as well as the influence on nanostructures caused by rapid thermal annealing (RTA) time and temperature of gold film, were studied. An average reflectance of 1.97% was obtained under optimized condition.
{"title":"Fabrication of micro- and nano- structures for antireflection by chemical etching method","authors":"C. Rong, X. Gu, W.P. Liu, W. Zhang, F. Zhang, L. Yuan, Y. Y. Wang, C. Peng","doi":"10.1109/3M-NANO.2013.6737452","DOIUrl":"https://doi.org/10.1109/3M-NANO.2013.6737452","url":null,"abstract":"Periodic pyramid and random nanostructure binary structures of single-crystal silicon wafer was fabricated by chemical etching method. Much lower reflectance of silicon wafer with these structures was obtained compared with that of single pyramid arrays. The morphology and reflectivity of these structures, as well as the influence on nanostructures caused by rapid thermal annealing (RTA) time and temperature of gold film, were studied. An average reflectance of 1.97% was obtained under optimized condition.","PeriodicalId":120368,"journal":{"name":"2013 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale","volume":"124 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127413192","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}
Through the molecular dynamics simulations, the ionic currents in physically realistic nanochannels with consideration of the thermal motion of channel walls are observed. It is found that the ionic current changes a little as the surface charge density increases from 0 to -0.3C/m2 with a huge decrease at -0.3C/m2 when the electric filed strength is 0.25V/nm. The Cl-ion current shows a decrease-increase profile as the surface charge density increases, while there is an increase-decrease trend in the Na+ ion current with the turning point at -0.075C/m2. By the statistic of the concentration and velocity distributions, the location of Na+ ions which provide main contribution to the current moves from the center of the channel to the charged surface as surface charge density increases from 0 to -0.225C/m2. The two parts included in current carriers have different concentrations and mobility. So the different contributions of the two parts Na+ ions and Cl-ions cause the feature of ionic current.
{"title":"Ionic current investigation in silicon nanochannels with molecular dynamics simulations","authors":"Yinghua Qiu, Jian Ma, W. Guo, Wei Si, Qiyan Tan, Yunfei Chen","doi":"10.1109/3M-NANO.2013.6737442","DOIUrl":"https://doi.org/10.1109/3M-NANO.2013.6737442","url":null,"abstract":"Through the molecular dynamics simulations, the ionic currents in physically realistic nanochannels with consideration of the thermal motion of channel walls are observed. It is found that the ionic current changes a little as the surface charge density increases from 0 to -0.3C/m2 with a huge decrease at -0.3C/m2 when the electric filed strength is 0.25V/nm. The Cl-ion current shows a decrease-increase profile as the surface charge density increases, while there is an increase-decrease trend in the Na+ ion current with the turning point at -0.075C/m2. By the statistic of the concentration and velocity distributions, the location of Na+ ions which provide main contribution to the current moves from the center of the channel to the charged surface as surface charge density increases from 0 to -0.225C/m2. The two parts included in current carriers have different concentrations and mobility. So the different contributions of the two parts Na+ ions and Cl-ions cause the feature of ionic current.","PeriodicalId":120368,"journal":{"name":"2013 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114309239","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 : 2013-08-01DOI: 10.1109/3M-NANO.2013.6737397
W. Lijun, D. Wei, Du Zhijiang, Zhan Yuchun
Flexible needle insertion is a promising technique in biopsy therapy and intervention treatment. In this paper, a novel flexible needle system is proposed based on mechatronics system design and synthesis. The proposed flexible needle system is separated into two parts, i.e. a needle body and an actuated tip. The needle tip is actuated by the shear piezoelectric actuators based on stick-slip motion principle. In the conventional design, the needle tip can be rotated since the needle body transmits the motion from the needle base. However, the rotation accuracy suffers from the friction torque which is generated between the needle body and the surrounding tissue. One of the main advantages of the proposed design indicates that the needle tip is directly driven at tip end instead of at base end, which avoids the uncertainties such as friction disturbance. In this paper, the conceptual design of the proposed system is introduced first, and based on that, a detailed dynamic model is also discussed, which is validated by the numerical simulation.
{"title":"Motion modeling and simulation of a flexible needle system with a piezo-actuated tip","authors":"W. Lijun, D. Wei, Du Zhijiang, Zhan Yuchun","doi":"10.1109/3M-NANO.2013.6737397","DOIUrl":"https://doi.org/10.1109/3M-NANO.2013.6737397","url":null,"abstract":"Flexible needle insertion is a promising technique in biopsy therapy and intervention treatment. In this paper, a novel flexible needle system is proposed based on mechatronics system design and synthesis. The proposed flexible needle system is separated into two parts, i.e. a needle body and an actuated tip. The needle tip is actuated by the shear piezoelectric actuators based on stick-slip motion principle. In the conventional design, the needle tip can be rotated since the needle body transmits the motion from the needle base. However, the rotation accuracy suffers from the friction torque which is generated between the needle body and the surrounding tissue. One of the main advantages of the proposed design indicates that the needle tip is directly driven at tip end instead of at base end, which avoids the uncertainties such as friction disturbance. In this paper, the conceptual design of the proposed system is introduced first, and based on that, a detailed dynamic model is also discussed, which is validated by the numerical simulation.","PeriodicalId":120368,"journal":{"name":"2013 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127248171","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 : 2013-08-01DOI: 10.1109/3M-NANO.2013.6737396
D. Wei, Shi Ruochong, Sun Pengfei, Du Zhijiang, S. Li-ning
A flexible parallel manipulator was proposed for high-precision pointing, which employed flexure hinges as passive joints and oriented its moving platform along all six degrees of freedom by means of six independent piezoelectric actuators. A right-circular flexure hinge with high motion accuracy and large displacement was designed based on performance analysis. The parameters of parallel mechanism were optimized by multi-objective optimization on the foundation of inverse kinematics. Moreover, workspace determination and simulation analysis were performed based on the final designed mechanism. Finally, a high-precision pointing system was built up and the performance tests had been implemented, which validated the proposed system satisfied the requirement of design targets. The concept and approach outlined can be extended to a variety of applications.
{"title":"Development of a piezo-actuated high-precision flexible parallel mechanism","authors":"D. Wei, Shi Ruochong, Sun Pengfei, Du Zhijiang, S. Li-ning","doi":"10.1109/3M-NANO.2013.6737396","DOIUrl":"https://doi.org/10.1109/3M-NANO.2013.6737396","url":null,"abstract":"A flexible parallel manipulator was proposed for high-precision pointing, which employed flexure hinges as passive joints and oriented its moving platform along all six degrees of freedom by means of six independent piezoelectric actuators. A right-circular flexure hinge with high motion accuracy and large displacement was designed based on performance analysis. The parameters of parallel mechanism were optimized by multi-objective optimization on the foundation of inverse kinematics. Moreover, workspace determination and simulation analysis were performed based on the final designed mechanism. Finally, a high-precision pointing system was built up and the performance tests had been implemented, which validated the proposed system satisfied the requirement of design targets. The concept and approach outlined can be extended to a variety of applications.","PeriodicalId":120368,"journal":{"name":"2013 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131083460","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 : 2013-08-01DOI: 10.1109/3M-NANO.2013.6737390
Wenrong Wang, C. Liang, Tie Li, Yuelin Wang
In this paper, graphene films were synthesized by chemical vapor deposition. Raman spectra and transmission electron microscope indicated the graphene films were few-layer. Al2O3 films were grown directly onto the surface of graphene transferred on SiO2/Si by H2O-based atomic layer deposition method. Experiments revealed that the distribution of physically adsorbed H2O molecules on the surface of graphene decided the morphology of Al2O3 film, and the O/Al ratio was close to stoichiometric condition of 1.5.
{"title":"Studies on H2O-based Al2O3 deposited on as-grown CVD graphene","authors":"Wenrong Wang, C. Liang, Tie Li, Yuelin Wang","doi":"10.1109/3M-NANO.2013.6737390","DOIUrl":"https://doi.org/10.1109/3M-NANO.2013.6737390","url":null,"abstract":"In this paper, graphene films were synthesized by chemical vapor deposition. Raman spectra and transmission electron microscope indicated the graphene films were few-layer. Al<sub>2</sub>O<sub>3</sub> films were grown directly onto the surface of graphene transferred on SiO<sub>2</sub>/Si by H<sub>2</sub>O-based atomic layer deposition method. Experiments revealed that the distribution of physically adsorbed H<sub>2</sub>O molecules on the surface of graphene decided the morphology of Al<sub>2</sub>O<sub>3</sub> film, and the O/Al ratio was close to stoichiometric condition of 1.5.","PeriodicalId":120368,"journal":{"name":"2013 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130856994","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 : 2013-08-01DOI: 10.1109/3M-NANO.2013.6737426
N. Ferreira, D. Metz, A. Dietzel, S. Buttgenbach, T. Krah, K. Kniel, F. Hartig
Three-dimensional micro probing systems based on silicon force sensors allow force measurements in the range of several μN. Their high sensitivity enables tactile measurements of three-dimensional micro- and nanostructures without leaving strong traces on the probed surfaces. However, their small sizes of 6.5 mm × 6.5 mm do not allow an easy handling and can lead to a breakage of the complete system rapidly. To improve the handling and the integration of these micro probing systems a new kind of probe head and an appropriate assembling method have been developed. In order to show the performance and the high reproducibility of microprobes for their use in coordinate metrology, many measurements have been carried out with a customary gear measuring instrument on a calibrated spur gear. The results have been compared to calibration values and the deviations are in the range of maximum some 100 nm.
{"title":"3D micro probing systems for gear measurements with nanometer-scale deviation","authors":"N. Ferreira, D. Metz, A. Dietzel, S. Buttgenbach, T. Krah, K. Kniel, F. Hartig","doi":"10.1109/3M-NANO.2013.6737426","DOIUrl":"https://doi.org/10.1109/3M-NANO.2013.6737426","url":null,"abstract":"Three-dimensional micro probing systems based on silicon force sensors allow force measurements in the range of several μN. Their high sensitivity enables tactile measurements of three-dimensional micro- and nanostructures without leaving strong traces on the probed surfaces. However, their small sizes of 6.5 mm × 6.5 mm do not allow an easy handling and can lead to a breakage of the complete system rapidly. To improve the handling and the integration of these micro probing systems a new kind of probe head and an appropriate assembling method have been developed. In order to show the performance and the high reproducibility of microprobes for their use in coordinate metrology, many measurements have been carried out with a customary gear measuring instrument on a calibrated spur gear. The results have been compared to calibration values and the deviations are in the range of maximum some 100 nm.","PeriodicalId":120368,"journal":{"name":"2013 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123364805","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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