Energy Technology Data Exchange (ETDEWEB)

Effect of alcohol solvent in mixing process on process on the microstructure and sintering behavior of ceramic-based composites was inestigated in detail. The mixture of fine ceramic powders was prepared through the conventional ball-milling method with various alcohol media. The particle distributions of fine ceramic powders were strongly dependent on the kind of alcohol employed during ball-milling. Ceramic-based composites were fabricated by hot-pressing the mixture of fine ceramic powders. Their microstructures and some mechanical properties of the ceramic-based composites were evaluated. It was found that the viscosity of alcohol, surface tension and contat angle greatly affect the sinterbility and some of the mechanical properties of ceramic-based somposites. (author)

Energy Technology Data Exchange (ETDEWEB)

Semiconductive crystalline PZT powders doped with Bi and K were synthesized by hydrothermal reaction at 200{degree}C for 48 hours. The synthesis of the crystalline powders became difficult with an increase in doped amount of Bi and K, and in Zr/(Ti+Zr) ratio. Since substantial amounts of Pb remained in solution after hydrothermal reaction, the addition of Pb in excess of 25% was necessary to obtain the stoichiometric composition of the PZT solid solution. Bi contents in the powders were identical to those in starting materials, while K contents were less than expected ones. The electromechanical properties of the sintered bodies could be precisely measured by an admittance-curve-fitting method. The electromechanical coupling factor and piezoelectric coefficient of the sintered bodies varied with the Bi content like those of specimens prepared by solid state reaction, and showed the maximum values at a given Bi content. However, the change in conductivity with the Bi content was ...

Energy Technology Data Exchange (ETDEWEB)

The single-electrode capacitance of a nano-porous carbon electrode used as an electric double layer capacitor was measured. The charged state of the electrolyte ion was discussed from the results. Single-electrode capacitance was not proportional to the specific surface area of the electrode. This implies that the whole surface of the electrode is not effective for the formation of an electric double layer. It is considered that edge orientation of the carbon structure would give a dominant contribution to capacitance. For measurements with aqueous solutions of various electrolytes, capacitance was about the same value for each salt compound. For aqueous acid solution, on the other hand, capacitance was twice to three times as large as that for salt compounds. This difference, however, became negligibly small if the concentration of electrolyte solution was lowered. Taking account of the hydrated ionic radius of each ion, it was considered that ions in salt solutions attach onto carbon ...

Energy Technology Data Exchange (ETDEWEB)

Described herein are the results of the FY1994 research program for analysis and evaluation for thin film solar cells. The study on quantitative analysis of hydrogen atoms in a plasma determines quantity of hydrogen atoms in the plasma of monosilane diluted with hydrogen. It is found, contrary to expectation, that quantity of hydrogen atoms in the plasma decreases as it is more diluted with hydrogen. The study on light-induced degradation of the thin chlorine-base amorphous silicon films confirms that the plasma CVD method with 20% of dichlorosilane gas added to monosilane gas produces the thin amorphous silicon film 3 times faster than the conventional method. The thin film has essentially the same defect density as the one prepared by the conventional method, showing good photoelectric characteristics. The thin film of chlorinated amorphous silicon has a 1 digit lower defect density than the conventional one of amorphous silicon, as revealed by the accelerated degradation test with ...