The behavior of nitrogen metastable molecules N₂ (A^₃∑+ μ)between parallel plane electrodes has been analyzed by solving the diffusion equation using the third kind boundary condition. Reasonable agreement between our theory and experimental results, has been obtained. In this paper, we extend the analysis for largely different reflection coefficients at each of electrodes. The relation among effective lifetime of metastables, reflection coefficients and gas pressure are discussed in detail.

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The characteristics of the L=2 modular sterallator designed by "the helical wind back method" has been calculated in detail. The results show that it has a relatively deep (-%) and wide (more than half of the radius of the outermost magnetic surface) magnetic well, and moderate magnetic shear for period of helical coil winding, M₁=18, M₂=3, and coil aspect ratio A=7. For this typical example, the number of moduler coils reduces to 42 from 54 of the original proposed modnzler coil system (M₁=24, M₂=3).

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MIM samples of Al/Polyimide LB Film/Au are prepared and DC voltage of several hundreds milivolts generated in the MIM samples is analyzed in the temperature range of about 30-70°C. It is indicated that the voltage generation is due to the difference of work functions between Al and Au, and the diffusion of carriers in LB film. The diffusion constant and the diffusion current of the carriers are calculated analytically. Furthermore, the conduction current due to generated voltage is analyzed. Using the diffusion current and conduction current mentioned above, DC voltage generated in the MIM samples can be analyzed in the cases of inserting the resistances 10⁸, 10⁹, 10¹⁰ and 10¹¹Ω in the outer circuit of the MIM, and the results of the analys coincides with the results of measurements of the voltage. There is no temperature dependence of the conduction current of the MIM sample, because polyimide film is very thin (about 30Å) and the thickness of the insulating layer is about 60Å (addition of thickness of Al₂O₃ natural oxide film of about 30Å).

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Amorphous and polycrystalline zincphtalocyanine thin films were deposited in this study, on indium tin oxide (ITO) substrates by means of a vacuum evaporation technique, and their electrochromic properties were investigated in the electrolytic solution of 0.5M natriumchloride solved in thyleneglycol. Basic characteristics of electrochromism were measured and observed as following: cyclic voltammetry, electron and anion behavior, VIS spectroscopy, coloration efficiency, memory properties and response time. The color transition was observed from blue to purple upon oxidation and from purple to blue upon rereduction. When potential was swept in a potentiogalvanostat, charge compensation was attained upon oxidation by injection of anions from the electrolyte to the thin film and upon rereduction by expulsion of anions. As anions may be more easily injected in amorphous films, those showed electrochromism more clearly in comparison with polycrystalline films. Coloration efficiency of 250.3cm²/C was obtained at 20°C. This value was independent on the structure of the thin film, and was large in comparison with that of WO₃. Coloration officiency of more than 200cm²/C was obtained in the electrolyte temperature range from 20 to 70°C. The oxidized state with a purple color of zincphthalocyanine was stably stored even in air.

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The circuit for compensating r. f. potential disturbance essentially consists of a capacitive probe and a feedback loop of its signal to the probe circuit has been developed. Output from the capacitive probe was fed through a phase shifter and an amplifier. The phase and the amplitude of the signal were adjusted until the probe characteristic curve is shifted toward the most positive voltage side. This was done by sweeping the probe current at a fixed d. c. probe voltage superimposed by r. f. voltage and by finding the phase and the amplitude to give the minimum current. We have analyzed the spectrum components of the plasma potential detected by the capacitive probe, which include up to 5th harmonics. Features of the present research are to expand the frequency band of the phase-shifter and the amplifier to 40MHz equivalent to the frequency of 3rd harmonics and to apply the compensation processes at every probe bias instead of compensating only at the floating potential.

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The radiation patterns of a line current near the dielectric elliptic cylinder have been analyzed as a boundary-value problem for the two-dimensional electromagnetic wave equation using Mathieu functions and modified Mathieu functions. No reports based on exact calculation of Mathieu functions with consideration of their convergence have been published because the complex eigenvalues of Mathieu functions cannot be calculated easily. Recently, computational programs for calculating the complex eigenvalues have been derived. Developing these programs we can prepare the computational programs for calculating the analytic solutions of the boundary-value problem for the radiation and scattering of a lossy dielectric elliptic cylinder by a line current. We describe, in this paper, the method of calculating complex eigenvalues of Mathieu functions, the convergence of the series of Mathieu functions and the radiation-pattern characteristics of an infinitely long filament of an electric current source parallel to the elliptic cylinder which has the complex relative permittivity ε_r ∗.

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The paper describes the discharge phenomena of a small air gap with ceramics composite-plane electrodes under pulse voltages. The discharge voltage decreases with increasing projection distance of ceramics from a comb-shaped metal electrode. Even if the projection distance is zero, the discharge voltage is lower than that of comb-shaped metal electrode. This shows that the discharge is extremely sensitive to the local high field caused by a triple junction. The surface discharge on ceramics occurs after the gap discharge, and it always initiates at the negative side irrespective of the polarity of the applied pulse voltage. These anomalous discharge characteristics are discussed on the basis of the experimental results.

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The propagation characteristics of a negative surface discharge having a rectilinear channel configuration were experimentally investigated under atomospheric conditions. To obtain such propagation, we employed a needle to knife-edged electrode system incorporating a thin dielectric film (PET, δ=50μm) and applied a negative impulse voltage (-8kV, 0.23/24μs) to the needle. Unlike the well-known surface discharge which indiscriminately spreads out in a stream from an electrode, in our system the discharge rectilinearly propagates along the knife-edged electrode. Moreover, a fairly large current flows along the channel and strong illumination occurs. A high-voltage probe was set up at half the length of the generated channel, being capable of measuring its potential distribution. The resistance of the channel was estimated using a relation between its potential difference and a current. The capacitance was also estimated using a relation between the charge and the potential distribution. In addition, e briefly discuss a model describing the propagation behavior of the rectilinearly channeled negative surface discharge.

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The flashover characteristics and process in air gap with floating metallic objects are investigated experimentally in the presence of unipolar ion flow field. In the present work, needle-to-plane electrodes of 120mm in gap length were used as the main gap electrodes and the shape of tested metallic objects was spheres with the radius of2, 10 and 15mm or needles of 5 to 40mm in length.
The experimental results show that the first corona is originated from the needle electrodes and the corona inception voltage is almost independent of the location of the floating objects, the gap between the floating metal and the plane electrode is locally bridged by spark when the floating metal is in the vicinity of the plane electrode, and the characteristics of flashover voltage versus the location of the floating metal are different completely with the shape of the floating metal and polarity of the applied voltage.

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In the case of a precision ac-resistance measurement, it is important to determine the change of resistance between ac and dc for the error factors refer to angular frequency ω because the resistance is normally calibrated at dc. The change of the resistance may be evaluated by the use of an ac-dc transfer resistor, of which frequency characteristics are calculable from the dimensions and the materials. This paper describes a parallel-wire-type ac-dc transfer resistor developed at the ETL using Ni-Cr alloy wire-resistor. The change of the resistance from dc up to 2kHz was estimated to be less than 1 part in 10^-8.

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A high-current plasma source using TiO₂ ceramics was fabricated and the performance characteristics were compared with the plasma source using Ni-Zn ferrite. It was found that the TiO₂ ceramics could be operated with lower inter-electrode voltage and the time lag in discharge, τ, was one tenth of Ni-Zn ferrite. The filament temperature immediately before the plasma was formed was estimated to be 770°C. This meant that the initial electron was emitted at a lower temperature. Therefore, the thermal loss due to diffusion was thought to be small and these results suggested that the TiO₂ ceramics was a suitable material for a high-current plasma source.

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Electrical breakdown strength of polypropylene film is measured with gold (Au) or aluminum (Al) evaporated electrode by applying linearly rising voltage at 100°C. The breakdown strengths strongly depended on anode metal, rather than the cathode metal. The samples with the Au anode give lower electrical breakdown strengths than those with Al anode. These experimental results are discussed in terms of the previous proposed numerical breakdown model based on the transient space-charge behavior caused by bulk-generated, electrode-injected and extraction carriers. The simulation suggested the electrical breakdown of polypropylene film at high temperature region was affected hetero-space charge formation at the anode, which is consisted of the carrier injection carriers from cathode, migrated to anode. The height of interfacial potential barriers between anode and film strongly influenced the formation of hetero-space charge through the carrier extraction to the anode, leading to the results that, electrical breakdown strengths of polypropylene film are strongly affected by anode metal rather than cathode metal.

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It is well known that treeing is one of the main causes of breakdown of CV cables. It has been also considered that the interface exists between two solid insulation materials become a weak point on the electrical strength of CV cables. Therefore, it is important to reseach on the tree growing properties when there exists an interface. For evaluating the interface effect on the AC tree growth, an experimental investigation has been carried out by preparing an interface between two cross-linked polyethylene(XLPE) blocks. This paper describes the experimental results under various interface conditions. It was found that the interface had a great influence on the tree growth. The time to breakdown was reduced by the interface in the present test conditions. Painting the silicone oil on the interface, not only reduced the time to breakdown but also prevented the breakdown through the surface of spec imen(B). And the pressure applied on the interface had a slight effect on the time to breakdown but on the tree growth pattern. With the increasing of applied voltage, phenomena above mentioned were more significant It is proposed that the discharge column activities and the gas pressure reduction in the tree channels play important roles in the present situation.

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Tetragonal zirconia films were prepared by RF sputtering on thermally grown SiO₂ layer. Films were characterized by X-ray diffraction and were found to be consist of polycrystalline tetragonal zirconia. The grain size increased as increasing substrate temperature up to 700°C. The oxygen sensor was fabricated with the zirconia film. The current increased as increasing the oxygen concentration. The films deposited by this method was found to be useful as the ion conductor of a thin film oxygen sensor.

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The effect of acid rain on the tracking resistance of organic insulating materials was studied by the IEC Publication 587 method in this paper. PP, PC, ABS, PS and PVC are evaluated each other after soaked in the solution of artificial acid rain for 20 and 45 days. Time to failure and the contact angle of the samples are investigated. The micro structure of sample surface is observed by SEM. And the tracking process is monitored by thermal video system. Test results show that the longer soaked period in the solution of artificial acid rain, the shorter time to failure and the smaller the contact angle of the samples. The mechanism of the effect of acid rain on the tracking resistance of materials is discussed furthermore. It's suggested that the acid rain can result in severe erosion damages which is mainly caused by the increasing of wetting and the decreasing of thermal resistance of test samples after soaked in acid rain solution.

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The water dissolution into the insulating oils deteriorates the insulating performance of the oils. Although we are paid attention to dissolving of the water into the oils, the situation or state of water has not been well investigated. Then the effect of water on the electrical properties had been discussed by the total amount of water without confirming the transportation of the water state under the electrical field.
In recent years, the relation between IR spectrum of a water molecule in liquid materials and its state has been studied, then it has become possible to observe directly not only the state of the water in the oils but also the transportation of the water state under the electrical field. In this paper, we measured the IR spectra of water in Di-Octhyle-Phtharate (DOP) before and after the electrical field was applied. As a result, the water behaved as a water cluster bound by DOP molecules. Over the 90% water clusters behaved as a water dimer, and the other was a water trimer or polymer. As comparing both of the IR spectra measured before and after the electrical field was applied, such the state of the water does not change under the electrical filed (20-100[kV/cm]). It means that the conduction current or tan δ can be determined by the content of the bound water clusters without considering the transportation of the water state.

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Simultaneous incorporation and deposition of Si by KrF excimer laser beam irradiation in a silane (SiH₄) gas ambient realize to form functionally gradient structure in stainless-steel 304. The process is referred to as the laser implant-deposition (LID). The basic model to achieve such a gradient structure is investigated by analyzing Si depth profiles and total quantities of supplied Si atoms (Si dose) for various experimental conditions. The theories of this model involve both of the photodecomposition of SiH₄ gas by KrF excimer laser photons and liquid-phase difusion of the dissociated Si atoms into the stainless-steel. The Si dose is empirically estimated by taking account of the photodecomposition and the mass transport theory. The Si depth profiles are calculated by the liquid-phase diffusion model using the estimated Si dose, showing good agreement with the experimental results. In addition, the hardness, the corrosin property, and the thermal stability of the gradient structure are discussed.

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