A method of analyses for the position resolved electron velocity distribution and transport properties in Skeady State Townsend (SST) conditions has been developed. In this method, the dispersion functions in position and energy are used in a similar manner as those in the flight time integral (FTI) method. Analyses to obtain the SST data are carried out in CF₄ at two values of E/N, 20Td and 50Td. The spatial variation of local transport properties are reasonably obtained throughout the position space between the cathode and the anode regardless of the equilibrium and the non-equilibrium situation even under the influence of electron attachment.

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An Electron Cyclotron Resonance (ECR) ion source using a reentrant coaxial cavity was newly developed. The reentrant coaxial cavity force microwaves to propagate into the plasma from an annular window of a discharge chamber side wall. Four ring magnets were settled on a center conductor to produce a ring-cusp shaped magnetic field. Microwaves of 2.45 GH_z were introduced into the discharge chamber from stronger side of the magnetic field. The ion source of 8cm diameter discharge chamber was tested in this experiment. The minimum flow rate of sustaining plasma was 2 sccm for Ar and 10 sccm for N₂ and O₂ with high coupling efficiencies above 80%. The plasma density was higher than the cutoff density for Ar but lower for O₂ and N₂. The maximum ion beam current of 1.26mA/cm² was obtained at a forward power of 304W of Ar.

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In order to get a new electroconductive composite, the vapor-grown carbon fiber (VGCF) has been applied to the thermoplastic resin composite, as a conductive filler. The stability of electrical conductivity of the composite is investigated.
The reslstivity of VGCF composite is 1.7×10^-1Ω•cm at room temperature which is one order smaller than that of commercial grade composites with carbon filler. The stability of electrical conductivity, under temperature change (-35-+60°C) and for exposure tests (at room temperature and at 60°C), the VGCF composites have high degree of stability. The stability of electrical conductivity of the present composites are superior to those of conventional carbon fibers such as PAN-based, under tensile stresses and bending stresses.It is suggested that the fine conductive networks in the present composites give rise to these desirable performances.

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The various properties of polyethylenes used for XLPE cable insulations were evaluated, and followings were cleared out. At first, as for the rheological characteristics, the molecular weight distribution is different among the polyethylenes which show the same MFR values. Secondly, as for the crosslinking characteristics, the number of several chemical functional groups in polyethylene molecules are different between that of before and after the crosslinking. And relations are observed between the crosslinking reactivity and the number of some specific double bond. Melting temperature decreases in contrast with the increase of the degree of crosslinking, which is due to the decrease of crystallinity of polyethylene. Thirdly, in terms of breakdown strengthes, they are also affected with the degree of crosslinking, especially in the high temperature regions. This is due to the increase of elastic modulus brought by the network formation with crosslinking reaction.

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With the progress of polymer chemistry in recent years, polypropylene and polyethylene of crystalline polymers have been used as the insulating materials, as a power cable and a power condenser owing to the high performance of electric insulation. But the spherulites are formed on the process of cooling these polymer materials after being melted. It has been said that there might be some relations between this spherulite and treeing degradation.
We made the specimens with different degrees of spherulites on the various colling conditions and we made tree occur by applying an alternating current high voltage to every specimens. In this paper, we examined about tree growth in a spherulite by means of an image processing technique.
The main results obtained are as follows:
(1) The shape of spherulite was clear after about 6.7 seconds when the nucleus occurred.
(2) It was possible to stop the growth of spherulite when the specimen was cooled in the water of 0°C immediately after it was melted in homoiothermal box and taken out.
(3) There were differences in tree shape and growth according to the positions of a needle point of electrode.
(4) Relations between the spherulite and tree became more distinct by using a pseudo color processing.

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Diamond-like carbon (DLC) films are deposited in a dc vacuum arc plasma with a graphite cathode. The arc current, the flow rate of hydrogen gas and the pressure are 50A, 10ml/min and O.05Pa, respectively. The substrate materials are Si (111), soda-glass and Mo. Process parameters are deposition time (3-30min). The films are analyzed by the laser raman spectroscopy and surface appearance of the films are observed with an optical microscope.
The results are as follows: (1) The films deposited under these conditions have diamond-like carbon structure. (2) The films deposited for 3min on Si or Mo and for 5min on glass wrinkle on the substrates. (3) The films deposited for more than 10min on Si and for more than 15min on glass crack and flake off the substrates. (4) The films deposited for more than 10min on Mo plainly stick on the substrate without any wrinkles or flakes.
It is found that plain DLC films are able to be produced by the vacuum arc deposition method if the deposition time is appropriately selected, while never by the conventional plasma CVD method.

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