A trajectory analysis of electron transport properties are executed by using extended flight time integral(FTI) method under elastic and inelastic anisotropic scattering. The anisotropy in scattering gives large butregular changes on the electron transport properties in contrast that the elastic momentum transfer andinelastic integral cross sections are maintained constant. The multi-term analysis seems to provide samevalues of drift velocity and of mean energy as those by FTI method, but give quite different values oftransverse diffusion coefficient DT. The reason of discrepancy is discussed in relation to the kinetic theory.

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An impulse discharge material processing system was developed to prepare high temperature oxide superconductingY-Ba-Cu-O thin film on MgO substrate at room temperature. The impulse voltages of 1/300μs were applied between two Y-Ba-Cu-O targetsfaced each other in a vacuum chamber. Optical emission of the impulse discharge plasmas was investigated using a spectroscope witha spectrometric multichannel analyzer. Decomposition dynamics and plasma temperatures of Y, Ba and Cu species were elucidated.Constituent ratios of the deposited films were measured with a x-ray photoelectron spectroscopy. A laser ablation technique using532nm YAG laser was also attempted for the Y-Ba-Cu-O thin film preparation, and the plasma and quality of thin film by the impulsedischarge were compared with the results by the laser ablation.
As the results, Y, Y⁺, Ba, Ba⁺ and Cu species were identified during the impulse discharge. Average temperatures of the species Yand Y⁺ in the impulse discharge were found to be lower than those by the laser ablation. Y component in thin film deposited by theimpulse discharge method was less than Ba and Cu components.

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Thermoplastics polyimide (TPI) insulated coaxial cable for use under high temperature and radioactive conditions was developed and its electrical and mechanical properties were evaluated in comparison with cable insulated with polyetheretherketon (PEEK) which is known for its superior heat and radiation resistant characteristics. According to experiments, the electrical and mechanical properties of TPI insulated cable are stable over a wide temperature range in comparison with PEEK insulatcd cable even after a 1.2MGy of γ-ray irradiation and 6-months heat aging at 220°C, indicating that TPI is superior for use as a heatand radiation-resistant cables covering material. The electrical properties of TPI cable observed, were within actual use requnirements, even under γ-ray irradiation up to 1, 000Gy/h.

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The new application of Pulsed Electro-acoustic (PEA) method to measure the attenuation and dispersion characteristics of acoustic wave propagation in soft polymer is proposed. The PEA method has been applied to the measurement of space charge distribution formed in dielectric materials. In this method, charge distribution is detected as the acoustic wave signals which are generated by the charges existing in the sample under an applied pulse voltage. In a soft polymer sample such as low-density polyethylene (LDPE), however, the attenuation and dispersion distort the acoustic waveform during the propagation through the sample. To recover the wave form, it is necessary to study the attenuation and dispersion characteristics in the sample. In this paper, the attenuation and dispersion characteristics of LDPE in frequency domain were studied using the PEA method. It was proved through the experiment that PEA method has an excellent performance as an easy and precise measurement method for estimating the attenuation and dispersion characteristics of polymers.

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Lithium secondary batteries using carbon as negative electrode based on Li insertion have been developed. In the present paper vapor-grown carbon fibers (VGCF), as an ideal carbon material in structure, with different crystallographic structure are applied as a negative electrode for the lithium secondary batteries with 1 mol LiClO₄/propylene carbonate electrolyte. The battery performances of the fibrous electrode are characterized as a function of the microscopic structure of the carbon fibers. And the c-axis repeat distances of the TEM pictures of lithium charged as well as the host carbon fibers are treated by using image analysis system. It is shown that Li are stored to form the 1st stage three dimensional intercalation compounds in well-ordered VGCF, on the contrary, in disordered VGCF electrodes Li are inserted between carbon layers. VGCF has been evaluated as one of the promising negative electrode material for Li secondary battery.

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The authors have been investigating the change of γ ^p on the surface of the treated PTFE by the discharge in smaller pd region, named the low pressure discharge. The γ ^p values were 10 times larger than those for RF discharge treatement. It was assumed from the results of XPS analyses that the increased γ ^p was due to introduction of carbonyl or carboxyl gtroups on the treated surface.
The authors had assumed that the polar groups maybe formed with the assistance of nitrogen metastable molecules on the PTFE surface. Then, two experiments were carried out. First, a PTFE film was immersed in nitorgen metastable rich condition and the surface energy of immersed sample was measured. Secondly, a PTFE film was immersed in the low pressure discharge that the number of metastables was reduced by UV irradiation to the discharge area and surface energy was measured.
These results are surmmerized in this paper and a formula for introduction process of the polar groups on the surface is proposed.

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We have performed annealing of double P⁺ ion implanted GaAs layers using short-duration laser irradiation (within less than one second) on a small region of 1μmφ. The induced damages have been evaluated by RBS-channeling technique and micro-Raman scattering measurements as functions of ion dose and dose rate. The annealing behavior has been investigated also by the Raman scattering measurements as a function of annealing time, ion dose and dose rate. From characteristics of laser annealing, the ion dose are roughly classified into four regions. In the case of low doses (Φ≤2x10¹²P/cm², stageI) crystallinity is recovered almost perfectly, while in the case of high doses (10¹⁴P/cm²≤Φ≤10¹⁵P/cm², stageIII) crystallinity is nearly recovered by laser solid phase epitaxy. On the other hand, in the case of intermediate region (2x10¹²P/cm2 _??_ Φ _??_ 10¹⁴P/cm², stageII) and very high dose region (Φ _??_ 10¹⁵P/cm², stageIV), recovery is worse and the recovery process is somewhat complicated. It is found that the recovery of crystallinity strongly depends on the ion dose rate for the intermediate dose region. It is also demonstrated that short-duaration laser annealing is useful for implanted GaAs and that ion dose rate is very important parameter for the laser annealing.

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Pulsed power generators with an inductive energy storage system can be designed compactly and economically, Opening switches are indispensable to pulsed power generators using the inductive storage system. Fuses of metal foil or thin wires placed in tamper have been used as opening switches because of their simplicity and reasonable high performance.
Here, resistance variation of thin copper wires in water as an opening switch was studied to obtain the basic data for design of an inductive energy storage pulsed power generator. The dimensions of a wire influence the relation between the resistivity and the energy deposited in the wire of unit mass. Nevertheless, it is desirable that its relation can be represented regardless the wire dimensions. The dependence of the changing rate of wire resistivity on the resistivity was obtained using the energy balance equation about exploding wires, as a result, phases of wire exploding were clearly confirmed and the influence of the dimensions was removed from the relation between the resistivity and the deposited energy in an early phase of the wire vaporization.

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