In recent years, research and development of the micro-fluid systems have been activated in the field of chemical technology and biotechnology. Micro-fluid systems are realized by micromachine technology and MEMS technology. Micro pump is an essential element for miniaturization of chemical analysis reaction systems. The aim of this research is development of a micro linear pump which will be built into micro-fluid systems. This pump aims to take a sample of very-small-quantity of liquids. Taking a sample of very-small-quantity of liquids reduce the amount used and waste fluid of a reagent. Full length and diameter of this pump are 32.5mm and 6mm respectively. The features of this pump are (1) the pump is built with actuator, (2) the gap of 7μm between piston and cylinder is achieved through fine machining process, and (3) micro check-valves of 2mm diameter made of stainless-steel film are fabricated and integrated. In this paper, the structure and the characteristics of this pump were shown. And the characteristics after improvement of micro check-valves were shown.

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Efficient uniform mixing is an essential process for chemical reaction. However, it is difficult to fabricate many tiny stirrers on reactor chips. This paper shows a new method promoting high-efficient chemical reaction in micro chamber. To stir chemicals and to accelerate reaction catalytic particles are driven electrostatically in micro chamber. Two driving methods have been evaluated; AC drive and DC drive. Evaluation of chemical reactions revealed the effect of this developed devices. In addition conveyance system of catalytic particles is necessary for particles exchange.

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We propose optically controlled micromanipulation tools that can work in sealed micro space. The micromanipulation tools constructed with several optically driven micromachines such as manipulators and separators. The optically driven micromachines were produced by high-speed two-photon microstereolithography. The micromachines are simultaneously controlled by an optical trapping technique based on radiation pressure of a focused laser beam. We have developed a laser-scanning manipulation system for the synchronized control of multiple micromachines. By using the manipulation system, we examined the driving performance of the manipulators changing the laser power, scale and thickness of the manipulators. We also evaluated the torque of micromanipulators. In addition, the synchronized driving of micromanipulators and a microseparator were demonstrated in a micro channel. Such cooperative control of optically driven micromachines offers versatile and powerful tools for micro total analysis systems for biological applications.

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A strain gauge based thrust measurement system has been developed, by fabricating a thrust balance with four columns. In order to compare the performance of the different types of strain gauges for ion thrust measurement, foil type strain gauges were bonded to the first column and semiconductor strain gauges were bonded to the second column. Whereas, thin film strain gauges of NiCr and Pt-W materials were deposited on to the third and fourth columns respectively. The strain gauges of a particular type in each column, connected in Wheatstone bridge configuration, were calibrated to measure the thrust produced using Lami's principle and the performance was studied. Strain gauge bridge sensitivities varied from about 6μV/mN to 115μV/mN and the non-linearity varied from about 0.98 % to 2.84 % for bridges formed by the different types of strain gauges. Details on the calibration and simultaneous comparative performance study of the system developed have been presented

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The present work is concerned on developing high sensitive and high performance SnO₂-based gas sensors for detecting indoor air pollutant formaldehyde gas. The film was deposited on an alumina substrate using R.F. Induction Plasma Deposition technique. Physical properties of sensing films were examined by SEM, XRD method. The sensors showed high sensitivity to typical HCHO gas at an extremely low gas concentration of 20 parts-per-billion (ppb) with quick response and recovery time at several minutes. The effect of the doping of various metallic additives on the gas-sensing properties and operating temperature dependency were also investigated in the work.

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