Microflow driven by AC electrothermal pumping electrolytes with high conductivity fluid (ACET) effect is explored in order to seek new methods for (more than 0. 02 S/m) at microscale. Based on the ACET theory, a p...Microflow driven by AC electrothermal pumping electrolytes with high conductivity fluid (ACET) effect is explored in order to seek new methods for (more than 0. 02 S/m) at microscale. Based on the ACET theory, a physical model for particle trapping is established by a set of electrostatics, heat transfer and fluid dynamic equations. Further, fluid velocity fields are predicted using the software FEMLAB. Experiments are performed which verify the numerical results. The experimental results show that with appropriate electrode design, ACET effect can work on fluids with conductivity up to I. 53 S/m and trap particles at a low voltage. ACET devices can be readily integrated on chip into a microsystem. This offers insight into designing ACET lab-chips.展开更多
To explore the application of the characteristics of metallic microparticles, alternating current electric trapping of the SU-8 microrods coated with a thin gold layer by the chemical approach is investigated. Positiv...To explore the application of the characteristics of metallic microparticles, alternating current electric trapping of the SU-8 microrods coated with a thin gold layer by the chemical approach is investigated. Positive dielectrophoresis is used to absorb the gold-coated SU-8 microrods at the edge of the parallel electrodes, thereby forming chains to connect the electrodes. This is a fast automatic microcircuit formation process. Moreover, a non-charged molecule is modified on the surface of the gold-coated SU-8 microrod, and the modified microrods are controlled by the alternating electric field to form a number of chains. The different chains between the parallel electrodes consist of various parallel circuits. In order to compare these chains with different electric surfaces, the impedances of the metallic and modified microrods are measured and compared, and the results show that the gold-coated microrods act as pure resistors, while the microrods functionalized by a non-charged molecule behave as good capacitors.展开更多
基金US National Science Foundation ( No ECS-0448896)Tennessee Science Alliance Award
文摘Microflow driven by AC electrothermal pumping electrolytes with high conductivity fluid (ACET) effect is explored in order to seek new methods for (more than 0. 02 S/m) at microscale. Based on the ACET theory, a physical model for particle trapping is established by a set of electrostatics, heat transfer and fluid dynamic equations. Further, fluid velocity fields are predicted using the software FEMLAB. Experiments are performed which verify the numerical results. The experimental results show that with appropriate electrode design, ACET effect can work on fluids with conductivity up to I. 53 S/m and trap particles at a low voltage. ACET devices can be readily integrated on chip into a microsystem. This offers insight into designing ACET lab-chips.
基金supported by the National Natural Science Foundation of China(Grant No.51075087)the Funds from the State Key Laboratory of Fluid Power Transmission and Control,Zhejiang University,China(Grant Nos.GZKF-201107 and GZKF-201004)the Foundation from the China Scholarship Council(Grant No.2009612129)
文摘To explore the application of the characteristics of metallic microparticles, alternating current electric trapping of the SU-8 microrods coated with a thin gold layer by the chemical approach is investigated. Positive dielectrophoresis is used to absorb the gold-coated SU-8 microrods at the edge of the parallel electrodes, thereby forming chains to connect the electrodes. This is a fast automatic microcircuit formation process. Moreover, a non-charged molecule is modified on the surface of the gold-coated SU-8 microrod, and the modified microrods are controlled by the alternating electric field to form a number of chains. The different chains between the parallel electrodes consist of various parallel circuits. In order to compare these chains with different electric surfaces, the impedances of the metallic and modified microrods are measured and compared, and the results show that the gold-coated microrods act as pure resistors, while the microrods functionalized by a non-charged molecule behave as good capacitors.