The irradiation of ultrasonic waves to liquid causes liquid flow toward the propagation direction of the ultrasonic waves. This paper proposes the application of this phenomenon, called acoustic streaming, to the development of micro-actuators such as micro-manipulators for small particles and micro-pumps for liquid. Since high-frequency ultrasonic waves induce acoustic streaming very efficiently only in the vicinity of the transducer, micro-manipulators are shown to be realised by using a two-dimensional ultrasonic transducer array and controlling electrical power supplied to each transducer. It is also concluded that micro-pumps could be developed by combining a transducer array with a topographic channel structure for liquid flow.

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We tried to synthesize a new class of MC60 compounds with M=Rb, Sr and Y by an electrolysis process from solution. Two kinds of solution, 1.5mmol/l-C60 Toluene and 0.1mol/l-M(ClO4)x (x=1, M=Rb; x=2, M=Sr; x=3, M=Y) N, N-Dimethylformamide, were filled in the cathode cell and the anode cell, respectively. An ion exchange membrane separated the solution. Electrochemical properties were measured for the electrolyte solution. A black film was deposited on a silver cathode plate after the electrolysis. Raman spectra revealed that C60 molecules existed and were polymerized in the films. Characteristic shape of particles were observed in the obtained film. The coexistence of both C60 and metal was confirmed in the particles by an energy dispersive x-ray spectrometer. The film was crystallized after a post annealing at 160°C in a vacuum. The film slowly cooled after the annealing had a polymeric body-centered orthorhombic M1C60 phase, while the rapidly cooled film revealed a face centered cubic phase. The polymeric Sr1C60 and YIC60 were new materials obtained in this work, though the polymeric Rb1C60 has been well known.

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Gas sensors for detecting SF₆ decomposition products are being actively pursued as low cost instrumentation for detecting and locating faults in Gas Insulated Switchgear (GIS). We developed an ampero-, potentiometric-, hybrid- solid state ionic sensor using high ionic conductive solid. The sensor responded to the changes in HF concentration ranging from 1 to 10wt. ppm in SF6 gas at 1 atm. as amperometric response, from 1 to 1000wt. ppm as potentiometric response. We have revealed that amperometric response for low HF concentration, and potentiometric response for wide range HF concentration on the same solid state ionic sensor.

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We have developed a microscope using a dynamic focusing lens suitable for micro parts assembling. With the microscope, real-time observation of three-dimensional micro parts was achieved. The dynamic focusing lens consists of a thin glass diaphragm having a specific thickness profile, a metal diaphragm with a glass plate, transparent liquid, and PZT unimorph actuators. When the actuators push the metal diaphragm, the pressure of the transparent liquid bends the glass diaphragm. Therefore, the curvature of the lens is changed according to the applied voltage of the actuators. When the actuator is activated at high frequency, the focal plane of the lens is rapidly shifted, and many images of different focus are obtained in a short time. When the lens is activated at 60Hz, an image of the entire object is obtained, as if the depth of field is expanded. It is caused by the afterimage effect of the human eye. By the mechanism, the depth of field is expanded about four times.

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Interactions between a lipid-protein membrane and taste substances were investigated using SPR (surface plasmon resonance). The used membrane was the LB (Langmuir-Blodgett) multi-layered film composed of DHP (dihexadecyl phosphate) and the sugar-binding protein ConA. The LB membrane including ConA showed larger responses to almost all the taste substances, such as quinine, caffeine, sucrose and NaCl than the LB membrane without ConA. Suggestion was also made on the interactions of astringent and pungent substances with the charged lipid LB membrane.

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Recently, some types of micromachined gyroscopes (angular rate sensor) have been reported. Micromachined gyroscopes are suitable for familiar products such as a VTR, auto mobile and toy, where cost effective and mass production are required. However, it seems that many of problems and difficulties for designing the micro gyroscopes still remain. This study deals with such design problems on micromachined gyroscopes. The paper includes discussions about the analysis of the mass movement according to applied angular rate, optimum design respect to product of the sensitivity and response frequency, some problems in peripheral circuitry, acceleration sensitivity, a method to drive a mass, and a problems on the temperature dependence.

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