The rapid increase in the usage of flat panel display brought its low cost and high performance electronic materials essential to the display. In particular, photosensitive silver pastes used for forming fine electrodes of large size Plasma Display Panels (PDP) should form thin and highly-uniform structures with a low electrical impedance. The present work studied the formation of silver paste film electrodes on a large plasma display panel. In order to prevent ‘side etching’ and ‘edge curl’ the film morphology was optimized. The absorbance and the ‘shading rate’ of the solid components of the film were examined for optimization. Photosensitive silver paste films with uniform thickness of about 1.5μm were prepared without the edge curl.

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Microporous silica glass powder was fabricated by thermal decomposition of phenyl functions in organic-inorganic hybrid glass derived from tetraethyl orthosilicate (TEOS) and phenyltriethoxysilane (PTES). Micropores smaller than 1μm were mainly formed after the phenyl functions were completely removed by the thermal decomposition in air at 600°C. Mesopores with pore radius of 4 to 10nm were partly formed because of partial segregation of phenyl functions in the hybrid glass. Macroscopic segregation of the phenyl functions could be prevented because each phenyl functions were directly covalently bonded to silicon atoms constituting the siloxane skeleton structure of the microporous glass powder. The porosity increased with the added molar fraction of PTES to TEOS because of the increase in the phenyl functions. Nevertheless, the porosity was constant irrespective of the molar fraction of PTES when it was above 40% since a certain volume fraction of the siloxane structure was required for retaining the percolated structure of the siloxane bondings.

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For a plug transportation in gas-solid two-phase flow, the prediction equations on particle velocity in a plug and pressure drop in a vertical pipe were formulated by considering fluidized particles. These equations well predicted the experimental data obtained with various solid-air mass flow rates, pipe diameters, and types of particles with the error within around 10%.
In order to confirm the validity of the suppositions introduced in deriving these equations, the particle velocity distributions within a plug in the axial and transversial directions of flow were analyzed by a high speed camera and PIV. As a result, there was very little distribution in particle velocity in a plug, indicating that the particles in a plug are fixed relative to each other and therefore they all move with the same velocity.

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The mechanical properties of a powder are determined from the yield locus. The yield locus is often determined by approximating the results of shear tests by Coulomb equation, or by Warren-Spring equation. Meanwhile, the yield characteristics of a powder are expressed by Roscoe condition diagram. In this diagram, the yield locus appears orthogonal to the normal stress axis at both ends. However, yield locus approximated by the Coulomb and Warren-Spring equations is not orthogonal to the normal stress axis at both ends. So, the abovementioned mechanical properties obtained from the yield locus are likely to be affected by the approximate expression of the yield locus.
In this paper, I propose an approximation equation for a yield locus which expresses both the shape of yield locus in Roscoe condition diagrams and the experimental results. Then, these yield loci obtained by our equation, Coulomb and Warren-Spring equations are used to determine the mechanical and flow properties of powder beds. These values are compared with each other in order to discuss the effect of an approximation equation on mechanical properties.

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Much attention has been drawn to “Biodiesel” as a renewable liquid fuel, but the production using alkali hydroxide resolving in the reactant is always accompanied by environmentally malign effluents. This problem is evitable by using calcium oxide as the solid base catalyst. The strong basic property under the reacting condition of including a trace amount of moisture enhanced the catalytic activity for the chemical reaction to produce biodiesel. For preparing the practical catalyst, calcium oxide was anchored onto silica. The composite powder can be formed into macro-porous pellet by controlling the densification, which may further enhance the catalytic effectiveness factor.

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