Polyimide LB film (PI), heterofilm of arachidic acid LB film (C₂₀) and 2-pentadecyl-7, 7', 8, 8'-tetracyanoquinodimethane LB film (C₁₅•TCNQ) were used for preparation of the following MIM structures.
Al/Al₂O₃/PI (4L)/Au, Al/Al₂O₃/C₂₀(12L)/C₁₅•TCNQ(4L)/C₂₀(12L)/Al
The voltage was generated in the present MIM in the case of connection of the resistance of 1011 Ω between the electrodes of the MIM. The voltage generation continues for more than 2 years and is continuing now.
Accordingly energy RI2 (R: resistance, I: current through the resistance) is consumed in the resistance R and the integrated value of the energy amount to 10-5 J which is much more than the energy 10-9 J stored at the initial stage in the MIM {10-9 J was calculated by (1/2) Cυ2 (C is capacity and υ is the generated voltage of the MIM)}.
Furthemore, it is discussed that there is the existance of finite generated voltage in stationary state in balance between diffusion current and conduction current.

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Voltage was generated in metal-insulator-metal (MIM) structure of Al/polyimide Langmuir-Blodgett (LB) insulating film/Au which was fabricated in 1986. It was shown in the present paper that temperature decrease caused by the voltage generation was ascertained by noncontact temperature measurement using a Vacuun Avalanche Photodiode. Temperature decrease of the MIM was O.026°C at 0.3 Vin voltage generation. This value of temperature decrease about coincides with theoretical value which was calculated assuming specific heat and specific gravity of polyimide LB film as 1 Jg^-1K^-1 and 1g/cm³. Therefore, the present MIM seems to be a energy converter which convert thermal energy to electrical energy.

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A new analysis of the up-and-down method is considered when sampled data give us not only the 2-valued information of breakdown and non-breakdown but also the values of breakdown voltages or flashover voltages. The conventional up-and-down method requires more than 40 trials and suitably tuned up-and-down distance to the standard deviation of an underlying normal distribution in advance; there may be chances that the estimates of the parameters of a normal distribution cannot be obtained numerically; the estimates of the standard deviation is highly biased when sample size is small.
The proposed analysis method gives us four major advantages; (1) only 10 trials are required if we need the same confidence interval of the estimate of the standard deviation by using the new analysis method as the confidence interval by using the conventional 40 trials up-and-down sequence; (2) a careful tuning of the upand-down distance is not needed; (3) the estimates of the parameters can be obtained whenever the sample size is larger than 10; (4) the biases of the estimates of the standard deviation and the low-percentile breakdown voltage are smaller than those obtained from the conventional up-and-down method.

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Space charge accumulation characteristics of chemically modified polyethylenes which were grafted with acrylates like acrylic acid and n-butylacrylate using reactive extrusion were investigated. In LDPE-g-Acrylic Acid (LDPE-g-AA), it was showed that the heterocharge found in low-density polyethylenes (LDPE) decreased with the increase of acrylic acid graft ratio and changed to the homocharge formation above 0.1wt% due to the introduction of carbonyls. Conduction currents and charge mobilities of LDPE-g-AA decreased with the increase of AA graft ratio, while the conduction mechanism remains unchanged. However, in the LDPE-g-n-Buthylacrylate (LDPE-g-nBA), the change of space charge accumulation characteristics were not observed and charge mobilities of them not affected by the graft ratio. The differences of space charge formation between two grafted polyethylenes were closely related to the ability of trap site in monomer grafted to LDPE and the chemical structure of it.

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Partial TSC curves have been limited in their evaluation method. In this paper, a new evaluation method is originally proposed. Three parameters that enable us to determine a TSC curve accurately can be determined through the method reconstructing some full curves from some partial curves. Especially, two parameters of escape frequency factor and charge density have first been evaluated from the objective partial TSC curves. Simulated result gives good accuracy for three parameters.

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To expand the field of ozone application, efficient ozone generation is the most important problem. A double discharge method, which generates diffuse glow discharge at atmospheric pressure, is used in the present research. This method has a larger discharge volume comparing with one of conventional method, such as silent discharge, surface discharge and so on. Thus we expect that it is possible to get a higher concentration and to be more efficient for ozone generation due to its discharge volume.
An O₂/N₂ mixture (air) was employed as a raw gas for ozone generation and adjusted at 2.0 [l/min] for all measurements. To get the diffuse glow discharge a rapid rise time over 0.8 [kV/ns] was required for the applied voltage and this value gave good agreement with that obtained in previous investigations. The generated ozone concentration increased with discharge repetition frequency and at 35 [Hz], where the deposited power of 1.4 [W], the maximum generated ozone concentration of about 550 [ppm] was obtained. The mean ozone yield was 95-110[gO₃/kWh] for all measurements. The limit of deposited power was 1.2-1.4 [W] due to the appearance of arcing.

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Hybrid ceramic type and normal type bearings used for a 3kHz high-repetition-rate XeCl excimer laser, which contained a high speed three-stage axial blower and a magnetic coupling whose rotating speed were 2, 000rpm to 8, 000rpm typically 3, 000rpm, have been evaluated in excimer laser gas and atmosphere, respectively. These bearings were tested from Dec./1987 to Mar./1991, actual using time was over 5, 000hours.
Only a few erosions in sintering additive alumina Al₂O₃ and yttria Y₂O₃ of a silicon nitride Si₃N₄ ceramic ball have been observed with a SEM photograph and an EDS method, but didn't affect for a long time operation. No corrosion in a flouried grease BARRIERTA IEL/V has been detected with FT-IR technique which indicated the ingredients of oil. A heavy erosion in inner and outer raceways made by SUS440C with Ni coating on the surface has been detected. Two of four hybrid ceramic type bearings were rocked between inner raceway and ceramic balls and all Ni coating of them were split away. Two normal type bearings used in atmosphere did indicate no erosion and no abrasion at just the same rotating speed and the using time.
For a long time operation, it is necessary to reconsider about the materials of the raceways, but the silicon nitride Si₃N₄ ceramic balls and the flouried grease BARRIERTA IEL/V are possible to use.

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In general, electromagnetic waves are reflected and refracted on the different kind of boundary phase such as solid/liquid. When ac voltage is applied to cell suspensions, the electric current wave is effected by the biological activity of cell membranes so that it becomes to include some harmonic components specific to the cells. This phenomenon is called nonlinear dielectric properties. Here we describe the nonlinear dielectric properties of Saccharomyces cerevisiae in some growth phase. The results showed that there were little harmonics late induction phase but apparent even-numbered harmonics for yeast suspensions in early stationary phase.

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Loss processes of the nitrogen metastable molecule N₂(A³Σ+u) in plane parallel electrodes have been investigated by us previously by solving the diffusion equation. Our procedure is based on an analysis using the third kind of boundary condition which can take account of finite values for the density of N₂(A³Σ+u)at the electrode surfaces. The values of the effective lifetime of N₂(A³Σ+u) calculated from this analysis were reasonably consistent with our experiments.
This paper describes the behavior of the effective lifetimes of N₂(A³Σ+u) in a cylindrical cavity. The analitical treatment of the diffusion equation for N₂(A³Σ+u) proposed by us is extended to the three dimensional space. We report the nature of the effective lifetimes of metastable molecule in the cylindrical cavity systematically.

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The carbon rod placed on the axis of two stub pipes was heated by microwave discharge in helium gas at the atmospheric pressure. When the length of carbon rod inside the stub pipe was adjusted to 1/4 of wavelength of microwaves, the matching condition for microwave power input was satisfied well. The high density plasma was produced around the open ends of stub pipes and the carbon rod was heated to the temperature higher than 3000K. As a result, a part of carbon rod was completely evaporated within a few minutes after the application of microwave power of 1.2kW.

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High-pressure, pulsed glow discharge has been studied for the excitation discharge in TEA gas lasers. Various instabilities occur in the subsequent discharge, which induce the arc and collapse for the highly-repetitive operation. In this paper, the influences of the gas density depletion on the high-pressure, pulsed glow discharge have been investigated eliminating the other instabilities such as shock waves, residual ions, discharge products and electrode heating. The gas density depletion was produced by utilizing a subsonic flow between the curved electrodes. The comparison has been made on the discharge occurred in the presence of the gas density depletion with that by the doublepulse experiment in a stable gas. The big gas density non-uniformity tends to cause the arc without the shocks, ions, discharge products and electrode heating. The transition from glow to arc discharge discontinuously occurs with respect to the gas density depletion. On the other hand, the second discharge in the double-pulse experiment becomes arc in much smaller gas density non-uniformity, and the transition from glow to arc occurs gradually. The arc discharge might be driven by some factors other than the gas density depletion.

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The authors discussed the effects of types of carbonyl groups on high-field conduction and breakdown for low density polyethylene (LDPE) films. LDPE films with carbonyl groups of terminal ester type were found to have a lower high-field current at 90°C than LDPE films with carbonyl groups in main chain. The do breakdown strength at 90°C of the former was slightly higher than that of the latter, but the impulse breakdown strength did not depend on the types of carbonyl groups. The breakdown strength depended on film density and melting point. Since the size of crystalline region in the latter was suggested to be larger than that in the former from the DSC measurement, it is concluded that the high-field conduction in LDPE films is explained by the conduction process through the sites in the interface region between crystalline and amorphous parts. However, the breakdown process in LDPE was not related to the type of carbonyl groups probably because the breakdown in LDPE is concerned with a filamentary thermal breakdown in a weak point in the amorphous region.

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This paper describes some factors of mica-alumina combined insulation deterioration based on breakdown tests, aging tests and material analysis at elevated temperature range of 550-825 Aé. The initial breakdown voltage of specimens were measured with an improved breakdown test method having less data scatter than conventional ones. The effect of applied voltage was quantitatively clarified through the difference of the life time among the specimens deteriorated with voltage stress and without voltage stress at elevated temperature. It is found that the more the electrode metal diffusion layer grows the lower the breakdown voltage becomes. It is found that the breakdown voltage can be estimated through the thickness of undiffused layer. The metal diffusion was estimated with an EPMA. Based on the experimental results, it is concluded that the metal diffusion into insulation is the primary factor of dielectric deterioration in mica-alumina combined insulation at elevated temperature.

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The semiconducting glaze insulators show excellent electrical performance under contaminated condition. In order to make mass production of such type of insulators, it is first necessary to determine the kind of the materials to develop such a semiconducting property and to decide an optimum resistivity of the semiconducting glaze from practical manufacturing technology point of view.
This paper describes the results of a series of investigation into the macroscopic surface resistivity to develop the expected superior electrical characteristics of insulators, the optimization of the volume resistivity of glaze itself, the optimum distribution of volume resistivity of the glaze over the actual insulator surface, etc. The chemical composition of the glaze ingredients and the manufacturing conditions are essential for the resultant glaze characteristics.

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Organic static induction transistors(SIT) are fabricated using copper-phthalocyanine (CuPc) evaporated films. The slit type Al gate electrode of the device is sandwiched by the CuPc films. Schottky junction is formed at the interface between Al gate electrode and CuPc films. From the experimental results, it is found that source-drain current can be controlled by the bias voltage applied to Al gate electrode. The device characteristics depend on the gate bias voltage and structure of Al electrode. Good static and dynamic characteristics of the transistors are obtained by choosing a proper slit structure of Al electrode.

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When we try to form a very low magnetic field environment using a superconducting wall like a cylinder, we expect magnetic flux is expelled from the superconductor under the cooling process by Meissner effect. It has been believed that, at least, if we cool a superconductor in a zero field environment, the superconductor has no magnetic fluxsoid. However, we found that, in actual, a self generating magnetic flux under the cooling process result in a magnetic field so larger than we expect to form a very low magnetic field enviromment. In this paper, we describe experiments and the mechanism of the self- generation of magnetic flux under the cooling process.

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