Temperature rises of a birefringent substrate (LiNbO₃) have been measured in an argon RF discharge plasma. The measurement method is based on monitoring the variation of natural birefringence with temperature by laser interferometry. Using this method, the dependence of substrate temperature rise on applied RF power and gas pressure has been investigated. The evaluation of the temperature curves shows that heat flux from the plasma towards the substrate is independent of time and temperature. The magnitude of the flux differs largely from the applied power, and approximately 0.4‰ of the power. By measuring electron density, electron temperature and plasma potential with Langmuir probe, the energy of the ions incident on the substrate is estimated. The ion flux towards the substrate is calculated from the energy of ions and is compared with the measured heat flux. The dependence on the applied power is in approximate agreement between those fluxes. The temperature distribution over the substrate thickness is simulated numerically using the finite difference method.

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This paper presents the removal of nitrogen dioxide (NO₂) in air by dielectric-barrier discharge. Using an electrode with needles, the discharge plasma was produced at remarkably low voltage. The discharge onset voltage is in a range of 2-3kV in effective value at atmospheric pressure. In this experiment, air was added with gas mixture of N₂ and NO₂ with the NO₂ concentration of 979 or 1, 056ppm. The NO₂ removal rate was almost attained to 100‰ at the flow rate of 4l/min under a condition that applied voltage and frequency are 2.8kV and 20kHz, respectively. The results show that there exists in applied voltage and frequency a certain region where this method is applicable to the NO_x removal.

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This paper describes the effect of barrier upon creeping discharge characteristics in SF₆, N₂ and their mixture. The barrier height effect on the discharge voltage was investigated under the positive pulse voltage. The discharge voltage increased as increasing the barrier height in SF₆ gas. On the other hand, the discharge voltage hardly changed with the barrier height in N₂ gas. In order to make clear the mechanism of the initial creeping corona, it was observed with the optical technique such as ultra-high speed electronic imaging system(IMACON 468).
As the result, creeping corona path revealed the difference in images under various barrier height. And the charge accumulated on the barrier induced with the initial corona in SF₆ gas could suppress the development of the later creeping corona in contrast with N₂ gas.

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Excimer sources which emit UV or VUV ray in the energy range of 5-10eV have a number of interesting applications. Especially, it is expected to apply photochemical reactions, for example, the photolytic deposition on semiconductor, because they are possible to cut most chemical bonds without any thermal reaction. Recently excimer lamp is paid attention to use at the large area surface modification.
In the case of excimer lasers, He, Ne or He/Ne diluent are generally used as a buffer gas for forming inverted population and stable laser operation. On the other hand, buffer gas plays an important role on excimer generation via three body reaction. As a silent discharge holds back to turn into an arc discharge, it is expected that dominant effect of buffer gas will be shown on excimer generation via three body reaction.
In this paper, effect of buffer gas on excimer generation is studied using some rare gases (Ar, He, Ne and Kr) as a diluent. As a result, intense excimer KrF^* radiation was observed in Ar or Kr diluent. For this reason, energy level in buffer gases is important factor on excimer generation. Then, it is concluded that contribution on excimer formation of buffer gas is mainly absorption of surplus energy on three body reaction.

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The efficiency of ozonizer using silent discharge is very low as compared with the theoretical value. Therefore, many researches have been carried out in order to improve the efficiency of ozonizers. But, we cannot expect to improve the efficiency without changing the process of ozone generation.
In this study, two high voltages are applied to the ozonizer which has three electrodes (the central, surface and outer electrodes) arranged coaxially, and the phase difference between applied voltages can be changed. The silent and surface discharges are superposed in the same space of the ozonizer.
In this paper, the optimum experimental conditions to improve the efficiency of ozonizer using the discharge superposition method are discussed. As a result, the followings are obvious. When two kinds of discharges are superposed under the condition using the central electrode as a common-grounded electrode, the maximum ozone yield efficiency is obtained, especially at the phase difference of about 180°. However, under the condition using the surface electrode as a common-grounded electrode, the ozone efficiency is higher at the phase difference of about 90° or 270° than at the other angles.

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The motion of bubbles in liquid nitrogen (LN₂) in a non-uniform electric field are observed in a microgravity environment just after release from the terrestrial gravity, The dynamic behavior of the bubbles is analyzed considering the electrohydrodynamics and thermodynamics, and is explained consistently by a theory including these forces. The shrink of the bubbles in supercooled LN₂ is discussed.

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In recent years, with the development of television and portable telephone, the wide-band transformer tends to be miniaturized. In this paper, the wide-band transformer is analized with the distributed coupled-line theory. As a main result of the analysis, the balance and unbalance transmission characteristics of the balun are remarkably improved in high-frequency range using delay line element for compensation. If the connected point S_w between coil winding and delay line is off the ground, the balance transmission band is increased about twice in low-frequency range. If the point S_w is grounded and if the impedance ratio m² is the less, the higher degree of unbalance attenuation can be obtained. The better balance transmission characteristic can be get, When the matching factor K→1/2 (optimum).
In addition, we describe that the inphase or anti-phase transformer can be made on the basis of our isolation wide-band transformer. The equivalent circuits of inphase and anti-phase wide-band n:1 transformers are obtained with our theoretical analysis and these can be made of the same transformer. The transmission characteristics of inphase and anti-phase wide-band thansformers are analized and the improved characteristics are obtained in the high-frequency range. The theoretical and experemantal values agree well over the wide frequency range 100KHz-1000MHz.

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The degradation mechanisms with absorption of water boiling are explored for epoxy composite filled with silica particles. The relations between volume fraction of silica particles and dynamic Young's modulus for epoxy composite are measured with the function of square root at boiling time. The silane coupling agents are used for improvent of degradation at interface between epoxy resin and silica partitles with water boiling. The adhesive effects between epoxy resin and silica particles for boiling of epoxy composites are evaluated with the reinforcing model for rubber-particles system.

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Photochemical etching (PE) treatment was performed on thick porous silicon (PS) after prepared by using anodization technique. The depth profile of photoluminescence (PL) was measured for these of PE treated PS wafer. The PL of PS without PE treatment was observed at near surface, however, this luminescence region was transferred from the surface to PS/Si substrate interface by the increase in the PE treatment time.
PS morphology and crystallinity were evaluated by scanning electron microscope (SEM) and Raman spectroscopy, respectively. It was clarified that PS had cylindrical pores, which consisted of honeycomb structure holding crystallinity, filled with microparticles inside of them. It was concluded that although the microparticle regions dominated the PL of PS, these were etched from the surface by PE treatment and then PL region shifted from the surface toward the PS/Si substrate.

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