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Microfluidic device embedding electrodes realizes cell manipulation with the help of dielectrophoresis. Cell manipulation is an important technology for cell sorting and cell population purification. Till now, the theory of dielectrophoresis has been greatly developed. Microfluidic devices with various arrangements of electrodes have been reported from the beginning of the single non‐uniform electric field to the later multiple physical fields. This paper reviews the research status of microfluidic device embedding electrodes for cell manipulation based on dielectrophoresis. Firstly, the working principle of dielectrophoresis is explained. Next, cell manipulation approaches based on dielectrophoresis are introduced. Then, different types of electrode arrangements in the microfluidic device for cell manipulation are discussed, including planar, multilayered and microarray dot electrodes. Finally, the future development trend of the dielectrophoresis with the help of microfluidic devices is prospected. With the rapid development of microfluidic technology, in the near future, high precision, high throughput, high efficiency, multifunctional, portable, economical and practical microfluidic dielectrophoresis will be widely used in the fields of biology, medicine, agriculture and so on.

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A carbon fiber-type Cu-Sn negative electrode was prepared for use in the Li-ion battery. The Cu 6 Sn 5 alloy layer was formed on the carbon fibers by electroplating methods. After heat-treatment at 400 • C, the as-plated Cu 6 Sn 5 was transformed into multiple phases composed of Cu 3 Sn, SnO 2 and Cu 6 Sn 5 phases. The resultant Cu-Sn-400 fiber-type electrode exhibited better cycle-life and high-rate performances than the Cu 6 Sn 5 alloy based one. Even after 300 cycles, 72% of the initial discharge capacity was maintained. The phase compositions of the charged and discharged electrodes were investigated by a synchrotron XRD analysis.For more than two decades, lithium-ion (Li-ion) batteries have been widely used as the power source of consumer electric devices, such as mobile phones, laptop computers and power tools. The research and development of this battery is now focused on applications in a hybrid electric vehicle (HEV) and electric vehicle (EV) because of its superior high energy-density. 1,2 Total energy management, which involves the energy storage and supply between a plug-in hybrid electric vehicle (PHEV) with a Li-ion battery and the power grid, is examined and introduced. 3,4 Furthermore, the demand of large-scale battery systems capable of delivering several hundreds of kWhs is gradually being extended to industrial applications, such as a battery-driven train, a wayside energy storage system for railways and stabilization of natural power generation. Verification tests have been carried out using the Li-ion battery 5-7 as well as a nickel-metal hydride (Ni-MH) one. [8][9][10] Meanwhile, enhancements in the battery performances, such as power, cycle-life, safety and costs, are the crucial issues for Li-ion batteries in order to realize its widespread use in industrial applications.At present, a copper(Cu) foil is typically used for the negative current collectors of the Li-ion battery. A slurry containing the activematerial powder is coated on a Cu foil substrate. To improve the energy density and cycle-life performance of the Li-ion battery, Ni-foam substrates have been used. 11 Moreover, a proposed three-dimensional (3-D) micro-battery design, in which the number of electrodes is configured in a non-planar geometry, offers a solution for highrate capability due to the effectively increased electrode/electrolyte interface. 12,13 These advanced 3D electrode configurations would lead to enhanced battery performances.Recently, fiber-type Ni(OH) 2 electrodes were developed for the Ni-MH battery using the electrodeposition method. 14,15 In these electrodes, individual carbon fibers were coated with a Ni(OH) 2 layer. The test cell using the fiber-type electrodes exhibited better highrate and cycle-life performances than that of the conventional one. In order to realize the 3D micro-battery, both the positive and negative electrodes would be expected to change to fiber-type electrodes. However, for the Ni-MH battery, it would be very difficult to prepare a fiber-type negative alloy electrode using the ele...

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The electrical characteristics of biological tissue is evaluated by establishing an electrical equivalent circuit with electrical impedance spectroscopy. The least squares method is used to realize electrical equivalent circuit fitting by using the developed portable electrical impedance spectroscopy system. The EIS system is used to obtain the impedance spectrum data of the measured biological tissue. In the experiment, the impedance spectrum data of eggs under different heating time were measured, and the established equivalent circuit model of eggs was fitted by nonlinear least squares fitting algorithm. Moreover, the electrical characteristics of the biological tissue are also revealed by numerical simulation with HANAI model. The experimental and simulation results show that the extracted equivalent electrical parameters can clearly characterize the variation of the internal change of components of biological tissues.