The characteristics of electrokinetic flow in a microchannel depend on both the nature of the surface potential, i.e. whether it is uniform or nonuniform, and the electric potential distribution along the channel. In this paper, the nonlinear Poisson-Boltzmann equation is used to model the electrical double layer and the Lattice Boltzmann Model coupled with the constraint of current continuity is used to simulate the flow field in a rectangular microchannel with step change surface potential. The results show that step change ion distribution caused by step change surface potential will influence significantly the electric potential distribution along the channel, the velocity profiles and the volumetric flow rate. This may indicate that if disturbance on the ion distribution due to nonuniform surface potential and velocity distortion is large and not negligible, the electric potential distribution along the channel in both pressure-driven and electroosmotic flow may not be linear.
{"title":"Lattice Boltzmann Simulation of Microfluidics with Non-uniform Zeta Potentials: Requirements of Flow Rate and Current Continuities","authors":"F. Tian, Baoming Li, D. Kwok","doi":"10.1109/ICMENS.2004.85","DOIUrl":"https://doi.org/10.1109/ICMENS.2004.85","url":null,"abstract":"The characteristics of electrokinetic flow in a microchannel depend on both the nature of the surface potential, i.e. whether it is uniform or nonuniform, and the electric potential distribution along the channel. In this paper, the nonlinear Poisson-Boltzmann equation is used to model the electrical double layer and the Lattice Boltzmann Model coupled with the constraint of current continuity is used to simulate the flow field in a rectangular microchannel with step change surface potential. The results show that step change ion distribution caused by step change surface potential will influence significantly the electric potential distribution along the channel, the velocity profiles and the volumetric flow rate. This may indicate that if disturbance on the ion distribution due to nonuniform surface potential and velocity distortion is large and not negligible, the electric potential distribution along the channel in both pressure-driven and electroosmotic flow may not be linear.","PeriodicalId":344661,"journal":{"name":"2004 International Conference on MEMS, NANO and Smart Systems (ICMENS'04)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116715221","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}
We have studied the influence of π-coupling on electronic and structural properties of self-assembled 1,4-dithiol benzene (HSC₆H₄SH) molecule with the first principle DFT-KS method. The isolated molecule shows well defined electronic properties, which drastically change once the molecule is packed into a dense 1-D molecular wire. The HOMO-LUMO gap for a dimer decreases by 1.2 eV when intermolecular distance changes from 6.9 to 3.3 Å, while it sharply decreases by 2.2 eV for a wire containing seven (7) molecular units. It is found that intermolecular distances between molecular units, as well as the number of molecules in the molecular wire are the two main correlated factors that influence the magnitude of the changes. In fact, the two parameters that influence the electronic structure properties of the wires are clearly related to magnitude of π-electron interaction in the vicinity of the HOMO-LUMO gap region.
{"title":"The Effect of π-Coupling on the Electronic Properties of 1,4-Dithiol Benzene Stacking","authors":"M. Layachi, Y. Savaria, A. Rochefort","doi":"10.1109/ICMENS.2004.141","DOIUrl":"https://doi.org/10.1109/ICMENS.2004.141","url":null,"abstract":"We have studied the influence of π-coupling on electronic and structural properties of self-assembled 1,4-dithiol benzene (HSC₆H₄SH) molecule with the first principle DFT-KS method. The isolated molecule shows well defined electronic properties, which drastically change once the molecule is packed into a dense 1-D molecular wire. The HOMO-LUMO gap for a dimer decreases by 1.2 eV when intermolecular distance changes from 6.9 to 3.3 Å, while it sharply decreases by 2.2 eV for a wire containing seven (7) molecular units. It is found that intermolecular distances between molecular units, as well as the number of molecules in the molecular wire are the two main correlated factors that influence the magnitude of the changes. In fact, the two parameters that influence the electronic structure properties of the wires are clearly related to magnitude of π-electron interaction in the vicinity of the HOMO-LUMO gap region.","PeriodicalId":344661,"journal":{"name":"2004 International Conference on MEMS, NANO and Smart Systems (ICMENS'04)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125104444","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}
This paper presents a new design of a closed-loop sigma-delta accelerometer using an acceleration prediction feedback element. Thanks to a Kalman state estimator associated with a Linear-Quadratic-Gaussian (LQG) controller, the proof mass is maintained near its position of equilibrium. Consequently, operating on the relatively small proof mass displacement makes it possible to enhance the performance of the sigma-delta converter. This architecture shows an increase of more than 20 dB in signal quantization noise ratio compared to conventional sigma-delta accelerometers and has the advantage of being a completely digital solution.
{"title":"Resolution Enhancement of a Sigma-Delta Micro-Accelerometer Using Signal Prediction","authors":"É. Colinet, J. Juillard, S. Guessab, R. Kielbasa","doi":"10.1109/ICMENS.2004.127","DOIUrl":"https://doi.org/10.1109/ICMENS.2004.127","url":null,"abstract":"This paper presents a new design of a closed-loop sigma-delta accelerometer using an acceleration prediction feedback element. Thanks to a Kalman state estimator associated with a Linear-Quadratic-Gaussian (LQG) controller, the proof mass is maintained near its position of equilibrium. Consequently, operating on the relatively small proof mass displacement makes it possible to enhance the performance of the sigma-delta converter. This architecture shows an increase of more than 20 dB in signal quantization noise ratio compared to conventional sigma-delta accelerometers and has the advantage of being a completely digital solution.","PeriodicalId":344661,"journal":{"name":"2004 International Conference on MEMS, NANO and Smart Systems (ICMENS'04)","volume":"88 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122853435","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}
A monolithically packaged SAW (Surface Acoustic Wave) radio transponder and pressure sensor is developed for the application to a TPMS (Tire Pressure Monitoring System). The device contains the wireless transponder, which converts analog signal into digital one without any auxillary electronic circuits and then transmits the converted data wirelessly. No power sources are needed for wireless transponder and pressure sensor. The touch-mode pressure sensor converts externally applied pressure into a capacitance, and the SAW radio transponder radiates sensor values as pulse train to the interrogation (measurement) unit. The realization of the mechanical A/D conversion is possible since the SAW radio transponder has been connected to the touch-mode capacitive pressure sensor. The SAW radio transponder and touch-mode sensor have been fabricated using a surface micromachining and a bulk micromachining technologies, respectively. The performance of the integrated, passive and wireless pressure sensor meets the design specifications such as linearity, sensitivity and noise figure. Finally, experimental results on the radio transponder and sensor without power source are presented.
{"title":"A Monolithically Packaged Cordless Sensor System Embedding MEMS A/D Converter and Saw Transponder","authors":"Jae-Geun Oh, Bumkyoo Choi, Seung-Yop Lee","doi":"10.1109/ICMENS.2004.12","DOIUrl":"https://doi.org/10.1109/ICMENS.2004.12","url":null,"abstract":"A monolithically packaged SAW (Surface Acoustic Wave) radio transponder and pressure sensor is developed for the application to a TPMS (Tire Pressure Monitoring System). The device contains the wireless transponder, which converts analog signal into digital one without any auxillary electronic circuits and then transmits the converted data wirelessly. No power sources are needed for wireless transponder and pressure sensor. The touch-mode pressure sensor converts externally applied pressure into a capacitance, and the SAW radio transponder radiates sensor values as pulse train to the interrogation (measurement) unit. The realization of the mechanical A/D conversion is possible since the SAW radio transponder has been connected to the touch-mode capacitive pressure sensor. The SAW radio transponder and touch-mode sensor have been fabricated using a surface micromachining and a bulk micromachining technologies, respectively. The performance of the integrated, passive and wireless pressure sensor meets the design specifications such as linearity, sensitivity and noise figure. Finally, experimental results on the radio transponder and sensor without power source are presented.","PeriodicalId":344661,"journal":{"name":"2004 International Conference on MEMS, NANO and Smart Systems (ICMENS'04)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131526221","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}
This paper presents a novel Ion Sensitive Field Effect Transistor (ISFET), as a pH sensor, read-out circuit that uses three Operational Floating Current Conveyors (OFCC). This read-out circuit provides a linear sensitivity to pH over a wide range (pH values 2-12). Moreover, it provides an output current that is linearly related to the measured pH. It uses only one type of active element (i.e. OFCC) that makes this circuit easier to be both integrated and fabricated using a conventional CMOS process. Our simulation results demonstrate that the read-out circuit works reliably and can be a suitable sensor read-out circuit for lab on a chip biomedical applications.
{"title":"A Novel pH Sensor Current Mode Read-Out Circuit Using Operational Floating Current Conveyor","authors":"Y. Ghallab, Wael Badawy","doi":"10.1109/ICMENS.2004.16","DOIUrl":"https://doi.org/10.1109/ICMENS.2004.16","url":null,"abstract":"This paper presents a novel Ion Sensitive Field Effect Transistor (ISFET), as a pH sensor, read-out circuit that uses three Operational Floating Current Conveyors (OFCC). This read-out circuit provides a linear sensitivity to pH over a wide range (pH values 2-12). Moreover, it provides an output current that is linearly related to the measured pH. It uses only one type of active element (i.e. OFCC) that makes this circuit easier to be both integrated and fabricated using a conventional CMOS process. Our simulation results demonstrate that the read-out circuit works reliably and can be a suitable sensor read-out circuit for lab on a chip biomedical applications.","PeriodicalId":344661,"journal":{"name":"2004 International Conference on MEMS, NANO and Smart Systems (ICMENS'04)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127775614","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}
In 1978 Marty et al. described for the first time the preparation of gelatin nanoparticles using desalting or desolvating agents. The desolvation process using acetone or other non-solvents works only with very low concentrations of gelatin (0.1%) [1]. By increasing the gelatin concentration in the solution the formation of aggregations during desolvation and cosslinking also dramatically increases. In 1985 the molecular weight of gelatin was described to be between 60000-90000 Da [2]. With improved analytical equipment, the specification of the molecular weight of one of the largest gelatin producers worldwide (DGF Stoess AG, Eberbach, Germany) is today from below 20000 to over 400000 Da. This shows the heterogeneity of gelatin and makes it more understanding why there are many difficulties in the preparation of nanoparticles from this substance.
{"title":"New Biocompatible Nanoparticles Based on Fractionized Gelatin as Drug Delivery Systems for Nucleic Acids and Peptides","authors":"C. Coester","doi":"10.1109/ICMENS.2004.113","DOIUrl":"https://doi.org/10.1109/ICMENS.2004.113","url":null,"abstract":"In 1978 Marty et al. described for the first time the preparation of gelatin nanoparticles using desalting or desolvating agents. The desolvation process using acetone or other non-solvents works only with very low concentrations of gelatin (0.1%) [1]. By increasing the gelatin concentration in the solution the formation of aggregations during desolvation and cosslinking also dramatically increases. In 1985 the molecular weight of gelatin was described to be between 60000-90000 Da [2]. With improved analytical equipment, the specification of the molecular weight of one of the largest gelatin producers worldwide (DGF Stoess AG, Eberbach, Germany) is today from below 20000 to over 400000 Da. This shows the heterogeneity of gelatin and makes it more understanding why there are many difficulties in the preparation of nanoparticles from this substance.","PeriodicalId":344661,"journal":{"name":"2004 International Conference on MEMS, NANO and Smart Systems (ICMENS'04)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134500581","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}
In this paper, we report the fabrication and characterization of electro-chemical actuator using platinum nanowire networks. Reversible strain amplitudes of ~ 0.04% have been observed by controlling the surface electronic charge density of the nanowire network through an applied voltage in an electrolyte solution. Displacement amplitudes of up to 3mm was observed for an applied voltage of only ±3 V, much smaller compared to most commercial piezoceramic materials. These results indicate the potential application of platinum nanowires for construction of artificial muscles and materials with tunable electronic properties.
{"title":"A Platinum Nanowires Actuator: Metallic Nano-Muscles","authors":"Shaoxin Lu, B. Panchapakesan","doi":"10.1109/ICMENS.2004.20","DOIUrl":"https://doi.org/10.1109/ICMENS.2004.20","url":null,"abstract":"In this paper, we report the fabrication and characterization of electro-chemical actuator using platinum nanowire networks. Reversible strain amplitudes of ~ 0.04% have been observed by controlling the surface electronic charge density of the nanowire network through an applied voltage in an electrolyte solution. Displacement amplitudes of up to 3mm was observed for an applied voltage of only ±3 V, much smaller compared to most commercial piezoceramic materials. These results indicate the potential application of platinum nanowires for construction of artificial muscles and materials with tunable electronic properties.","PeriodicalId":344661,"journal":{"name":"2004 International Conference on MEMS, NANO and Smart Systems (ICMENS'04)","volume":"96 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134526760","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}
J. Mizuno, T. Harada, T. Glinsner, M. Ishizuka, T. Edura, K. Tsutsui, H. Ishida, S. Shoji, Y. Wada
We have fabricated and evaluated the mechanical, optical and fluidic characteristics a 50µm wide and a 30µm deep micro-channel device produced by hot emboss and direct bonding of PMMA plate with dimensions of 20mm × 20mm × 1mm. The fabricated micro-channel device was evaluated the bond strength, which was confirmed to be high enough for practical use as well as for quite severe cleaning conditions as ultrasonic cleaning in pure water. The optical loss around bonded interface was also evaluated and no increase in the light absorption was observed. The above results confirmed that the hot emboss and direct bonding technologies for micro-channel manufacturing using the PMMA plates realizes high performance micro channel devices.
{"title":"Fabrications of Micro-Channel Device by Hot Emboss and Direct Bonding of PMMA","authors":"J. Mizuno, T. Harada, T. Glinsner, M. Ishizuka, T. Edura, K. Tsutsui, H. Ishida, S. Shoji, Y. Wada","doi":"10.1109/ICMENS.2004.66","DOIUrl":"https://doi.org/10.1109/ICMENS.2004.66","url":null,"abstract":"We have fabricated and evaluated the mechanical, optical and fluidic characteristics a 50µm wide and a 30µm deep micro-channel device produced by hot emboss and direct bonding of PMMA plate with dimensions of 20mm × 20mm × 1mm. The fabricated micro-channel device was evaluated the bond strength, which was confirmed to be high enough for practical use as well as for quite severe cleaning conditions as ultrasonic cleaning in pure water. The optical loss around bonded interface was also evaluated and no increase in the light absorption was observed. The above results confirmed that the hot emboss and direct bonding technologies for micro-channel manufacturing using the PMMA plates realizes high performance micro channel devices.","PeriodicalId":344661,"journal":{"name":"2004 International Conference on MEMS, NANO and Smart Systems (ICMENS'04)","volume":"35 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114021938","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}
Recent three topics of Nanotechnology Glass Project were described. (1) A proton-conducting hybrid material was fabricated using a glass plate with nano-pores. The conductivity of the hybrid glass plate was comparable to Nafion, and no corrosion or degradation observed up to 120°C. (2) Nano-particles of CdTe were synthesized in a water solution and embedded in the glass matrix using a sol-gel method. The emission quantum efficiency pf 3% was attained. (3) Deep dry etching followed by overcladding buried the DOE with a deep groove inside a Si0₂ plate, which was used for fabrication of an ultra small demultiplexer.
{"title":"New Functions Elaborated in Oxide Glasses by Nanotechnology","authors":"J. Nishii, K. Hirao","doi":"10.1109/ICMENS.2004.114","DOIUrl":"https://doi.org/10.1109/ICMENS.2004.114","url":null,"abstract":"Recent three topics of Nanotechnology Glass Project were described. (1) A proton-conducting hybrid material was fabricated using a glass plate with nano-pores. The conductivity of the hybrid glass plate was comparable to Nafion, and no corrosion or degradation observed up to 120°C. (2) Nano-particles of CdTe were synthesized in a water solution and embedded in the glass matrix using a sol-gel method. The emission quantum efficiency pf 3% was attained. (3) Deep dry etching followed by overcladding buried the DOE with a deep groove inside a Si0₂ plate, which was used for fabrication of an ultra small demultiplexer.","PeriodicalId":344661,"journal":{"name":"2004 International Conference on MEMS, NANO and Smart Systems (ICMENS'04)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117237539","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}
A miniaturized piezoresistive six-degree of freedom (6DOF) accelerometer has been developed and fabricated using bulk micromachining technology. Most accelerometers developed so far, sense accelerations in only three axial directions. This accelerometer measures three components of linear acceleration and three components of angular acceleration on three orthogonal axes in the frequency bandwidth of 300Hz. The average measured sensitivities of the fabricated sensor for linear accelerations and angular accelerations show a cross-axis sensitivity of <2%. Comparison of the obtained experimental results and finite element simulation shows good agreement. The sensor is ideal for use in biomechanical research applications such as the study of human gesture recognition systems.
{"title":"Design & Fabrication of Piezoresistive Six Degree of Freedom Accelerometer for Biomechanical Applications","authors":"R. Amarasinghe, D. Dao, T. Toriyama, S. Sugiyama","doi":"10.1109/ICMENS.2004.48","DOIUrl":"https://doi.org/10.1109/ICMENS.2004.48","url":null,"abstract":"A miniaturized piezoresistive six-degree of freedom (6DOF) accelerometer has been developed and fabricated using bulk micromachining technology. Most accelerometers developed so far, sense accelerations in only three axial directions. This accelerometer measures three components of linear acceleration and three components of angular acceleration on three orthogonal axes in the frequency bandwidth of 300Hz. The average measured sensitivities of the fabricated sensor for linear accelerations and angular accelerations show a cross-axis sensitivity of <2%. Comparison of the obtained experimental results and finite element simulation shows good agreement. The sensor is ideal for use in biomechanical research applications such as the study of human gesture recognition systems.","PeriodicalId":344661,"journal":{"name":"2004 International Conference on MEMS, NANO and Smart Systems (ICMENS'04)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123167479","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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