The effect of grinding on physicochemical stability of mefenamic acid polymorphs was investigated by using powder X-ray diffraction （PXRD）, differential scanning calorimetry （DSC） and fourier transform infrared spectra （FT-IR） methods. The relative humidity （RH） in a centrifugal ball mill was controlled at 4, 50, 75 and 97％ RH during the grinding. It was found that form I transformed into form II through the amorphous solid during the grinding and the crystalline transformation was affected by the environmental humidity. On the other hand, form II reduced the crystallinity and showed equilibrium after reversible repeating of crystallization and amorphization at the all humidity conditions.

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In order to prepare a crack-free and continuous photocatalytic film by a simple process, simultaneous electrophoretic deposition （EPD） of TiO₂ nanoparticles with submicron-sized Al₂O₃ particles to obtain their composite film was investigated. Generally, a deposit film of nanoparticle without cracking is not easily obtained by EPD ; however, it was found that mixing of the two starting particles with different size inhibited cracking during drying after deposition. Amount of TiO₂ in the composite films was almost the same as the starting suspensions. Although the durability of the film in water just after EPD was relatively low, it was largely improved by firing at 200～400℃. The composite films containing smaller amount of TiO₂ in this study showed similar level of photocatalytic property to those containing larger amount. It would be due to the porous microstructure of the films containing smaller amount of TiO₂ nanoparticles.

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Delayed coker is one of the most popular upgrading processes of heavy residue. The coke produced from delayed coker is usually regarded as petroleum coke for fuel. On the other hand, careful selection of feedstocks allows production of needle coke. Needle coke is one of the highest value-added products from the upgrading process of heavy residue. And it is applied for making graphite electrodes for electric arc furnaces because of high crystalline and purities. These days high performance needle coke is also applied for carbon materials for EDLC.

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