Silica films were successfully prepared on a polybutyleneterephthalate (PBT) substrate by dip coating using a perhydropolysilazane (PHPS) / polydimethylsilazane (PDMS) solution. The effect of thermal treatment on conversion from PDMS / PHPS to silica was investigated in detail by using SEM and FT-IR. The prepared Silica film had a thickness of 160 nm with a smooth surface and was crack free at 50 mass% of PDMS. The color pollution on silica films was characterized using a color meter. The resistance to color pollution was highest when the PDMS content was 25 mass%. The mechanical properties of silica films were also examined by performing pencil hardness and Vickers hardness tests. The Vickers hardness of the silica film decreased with increasing PDMS content. The pencil hardness of the silica film was 9 H, regardless of the PMDS content.

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LiMn₂O₄ and Li_1.09Mn₂O₄ powders were prepared by spray pyrolysis with aqueous solution of manganese carbonate. The dispersion stability of manganese carbonate was influenced by pH of aqueous solution. The particle characteristics of LiMn₂O₄ and Li_1.09Mn₂O₄ powders were determined by XRD, SEM and BET. SEM photograph showed that LiMn₂O₄ powders had spherical morphology with porous microstructure and consisted of primary particles. XRD revealed that crystal phase of LiMn₂O₄ and Li_1.09Mn₂O₄ powders were good agreement with spinel phase. The dischargeable capacity of LiMn₂O₄ cathode was 125 mAh/g at 1C. The dischargeable capacity of Li_1.09Mn₂O₄ cathode was 107 mAh/g at 1C. The dischargeable capacity of Li_1.09Mn₂O₄ cathode exhibited high cycle stability compared with that of was LiMn₂O₄ cathode.

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Spherical C/LiMn_1-XM_XPO₄ (M=Mg, Zn X=0, 0.01, 0.05, 0.10) precursor powders were successfully prepared by ultrasonic spray pyrolysis. The C/LiMn_1-XM_XPO₄ were obtained by heating at 973 K for 3 hours under argon/hydrogen (5%) atmosphere. The crystal phases of all samples had an olivine structure with a Pmnb space group and the impurity phase peak was not observed. The average particle size was approximately 0.7 μm. The electrochemical properties of the C/LiMn_1-XM_XPO₄ cathode were estimated by the rechargeable capacity and cycle performance. Electrochemical measurement revealed that the discharge capacity was improved by doping foreign metal such as Mg and Zn ion. The first discharge capacity of C/LiMn_1-XZn_XPO₄ (X = 0.1) cathode was approximately 60 mAh/g at 0.1 C. It was steady cycling characteristics.

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The magneto-orientation of mordenite zeolite during slip casting processes in a 12 T strong magnetic field was investigated using a commercial powder. When the as-received commercial powder was used, no orientation was observed. On the other hand, the mordenite zeolite was preferentially b-axis-oriented in the compacted disk prepared from powder classified by sedimention. Particle size distribution measurements revealed that agglomerated secondary particles larger than 2.8 μm in size were removed by the sedimentation classification.

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TiO₂ nanotube array film was synthesized by anodic oxidation of a Ti plate in NH₄F electrolyte. The film was broken to nanotubes by ultrasonication. The nanotube powder was mixed into TiO₂ nanoparticle paste. The paste was used in ceramics porous electrodes dye-sensitized solar cells.

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Fine powder of LiCoO₂ was prepared by mechanical milling. The SEM photographs of the LiCoO₂ powder which was prepared by various treatments. By grinding, grain size became smaller than that of no grinding sample. The grain size of grinding for 5 h was between 100 nm and 5 μm. By sintering after grinding, fine particles showed grain growth. The particles were rounded at the corner and the plate structure was observed by sintering at 1073 K. In XRD measurements, the crystal is distorted after grinding and after sintering at 873 K. By sintering at 1073 K, however, the distortion was not observed and the crystal growth was proceed by sintering at higher temperature. In charge-discharge measurements, the discharge capacity was lower in all samples than no grinding sample at low current density. In the samples sintered at 1073 K, the discharge capacity was highest in all samples at high current density.

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The compaction of a SiAlON phosphor powder was performed by electrophoretic deposition (EPD). The SiAlON phosphor films were filled with SiO₂ for improved adhesion to the glass substrate. The TEOS (tetraethoxysilane Si(OC₂H₅)₄) or TEMOS (tetramethoxysilane Si(OCH₃)₄) sol-gel precursor was impregnated in the SiAlON deposited film, then thermally treated at 773 K. The optical and mechanical properties of the SiAlON phosphor-SiO₂ composite films were also characterized.

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Spontaneous amorphization of ibuprofen (IB) by the coexistence of its solvent vapor and polymeric matrix, hydroxypropyl methylcellulose (HPMC), were elucidated by combining X-ray diffractometry, mid- and near-IR spectroscopy, and thermal analyses, together with the stability test of the non-crystalline IB by prolonged exposure to water vapor. The non-crystalline state of IB was achieved by the recombination of hydrogen bonds from intracrystalline ones to intermolecular ones between IB and HPMC. Coexistence of the solvent molecular species, either methanol or ethanol, significantly increased the stability of the non-crystalline states of IB. Since IB globules of 20－50 nm were observed by TEM, IB in a non-crystalline state cannot be regarded as a perfect molecular dispersion. We therefore attributed the apparent stability increase to two aspects, i.e., (1) molecular interaction between IB and HPMC by abridging ethanol or methanol molecules via both hydrogen bonds and hydrophobic effects, and (2) retardation of nucleation and growth by suppression of IB molecular mobility by IB-HPMC network structure.

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  The SOFC cell composed of an LSGM solid electrolyte and LDC buffer layers was fabricated. The formation of the LDC/LSGM/LDC tri-layer on the NiO-YSZ substrate was performed by a sequential electrophoretic deposition (EPD) technique. The performance of the cells was evaluated at temperatures between 500 and 800 ℃ using H₂ and air as the fuel and oxidant, respectively. The cell's open circuit voltage (OCV) of about 0.8V is lower than 1.1V which is the theoretical OCV of the LSGM electrolyte. This suggests that the dense LDC layer may work as the electrolyte in place of the LSGM. It is considered that the microstructure of the LDC buffer layer should be controlled to improve the cell performance.

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