Polymer Blend Precursors for Si-C-O ceramics were prepared from Polycarbosilane (widely used for ceramic fiber precursor) and methyl hydrogen silicone oil (Industrial popular material). Reflux treatment was effective to increase substantial ceramic yields beyond the expectation of composite law. Shift of Si-H band after the reflux treatment is also observed. The chemical interaction between different polymers during the treatment is suggested. Melt spinning of the prepared precursors was also possible. The shape and thickness of the obtained fiber, however, highly depended on the preparation conditions of the starting precursors.

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Fine particles of amorphous SiO2 with TiO2 coating were prepared from industrially-wasted silica powder by alkoxide method. Titania layer on the particle surface was anatase phase even after heat treatment at 1200 degree, meaning that the phase transformation of anatase to rutile was retarded in this system. The product exhibited the high ability for decomposition of methylene blue in water.

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TiO₂-SiO₂ wet gel was prepared by hydrolysis of Ti(n-OC₃H₇)₄ and Si(OC₃H₇)₄ in a 2-propanol solution with acid catalyst. The solvent in the wet gels was supercritically extracted in CO₂ at 60^oC and 22Mpa. The as-extracted aerogel with particle diameter about 5nm, BET specific surface area of 365m²/g and total pore volume of 0.20cm³/g contained anatase nanoparticles. The anatase phase was stable after calcinations at temperatures up to 1000^oC, and BET specific surface area, total pore volume and average pore diameter did not change significantly after calcinations at temperatures up to 900^oC. Effects of SiO₂ on stability of anatase TiO₂ and on the microstructure of the calcined aerogels were discussed.

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Zeolite-carbon composites were successfully synthesized by a combined process of calcination and carbonization in the N2 atmosphere followed by a hydrothermal treatment in alkaline aqueous solution from industrial wastes. It was found that the composites had micropores and mesopores with the ability toadsorb water vapor up to an amount of 20 mass%. The composites also demonstrated the capacity to absorb electromagnetic wave in the W-band frequency range (75-110 GHz) characterized as a reflection loss higher than 20 dB at the resonant frequencies. The resulting composites have potentials to be used as high value-added environmental materials such as building material with heat-insulating and humidity-controlling capacity, exhaust gas purification component, metal ion and organic pollutant adsorbing material and so on.

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Ni-based catalyst for CH₄ dry reforming has been developing yet because of Ni sintering and low resistance against coking for this reaction. In this study, conversion of the waste into CH₄ reforming catalyst and its performance have been investigated. Ni-based sample prepared from this waste prevented from Ni sintering and also had relatively high CH₄ conversion and stability.

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Yttria film was synthesized by laser chemical vapor deposition (LCVD) using Y-dpm (dpm = dipivaloymethanate) precursor. The influence of substrate pre-heating (Tpre) on the deposition rate R was studied. From R.T. to 773 K Tpre and laser power (PL) from 205 - 250 W, deposited films were dense with equiaxed grains increased with Lp. The influence of the deposition conditions on the film deposition rate was also studied and the deposition rate increased with Tpre and PL. So far, the highest growth rate of 300 um/h was achieved at Lp = 250 W and Tpre =773 K.

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Analysis of the change in the state of chemical bond at phase transition of dielectrics is important to control the dielectric properties. However, there are not enough investigation results of those. The change in the state of chemical bond around phase transition temperature of BaTiO3 as typical dielectrics were investigated. Observed O1s peak was able to deconvolut to two peaks. Peak position was shifted to high binding energy and FWHM was changed to small value respectively with increasing temperature from 120C to 150C. Furthermore, the values of changes between deconvoluted two peaks were different. It was considered that those changes were owing to the structure change of BaTiO3 at around phase transition.

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Analysis and control of crystallization process of glasses are important to tailor the dielectric properties of glass-ceramics. In general, differential scanning calorimeter (DSC) or differential thermo analysis (DTS) are applied to analyze crystallization process. However those methods can't analyze the change in the state of chemical bond. It is expecting that the high temperature measurement of XPS spectrum is excellent method to analyze the change in the state of chemical bond. In this study, possibility of high temperature measurement was verified using Li-B-O glass as the sample. The peak positions and FWHMs of O1s and B1s peaks were shown different relationships from 200C to 500C of measurement temperature. Those changes owing to the structure change of glass during glass transition and crystallization was considered.

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Aluminum nitride (AlN) is a promising AE sensor element for high temperature environments like gas turbines and other plants because AlN maintains its piezoelectricity up to 1200˚C. Highly c-axis-oriented AlN thin film sensor elements were prepared on silicon single crystal by rf magnetron sputtering. High temperature AE sensors were developed using these elements. The sensor characteristics were evaluated at elevated temperatures from 200 to 600˚C. It was confirmed that the AE sensor worked at 600˚C and was not deteriorated after elevation to 600˚C. But its sensitivity was still low and the structure of the AE sensor case should be improved.

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Aluminum nitride (AlN) is a promising pressure sensor element for high temperature environment like a cylinder of an automobile engine and other plants because AlN maintains its excellent durability and heat-resistance. Highly c-axis-oriented AlN thin film sensor elements were prepared on silicon single crystal by rf magnetron sputtering. The evaluation apparatuses for pressure sensors at a room temperature and high temperatures were developed and the sensor characteristics were evaluated. The linearity and good frequency characteristics were confirmed at pressures from 0.1 MPa to 1.6 MPa at a room temperature compared with those of a commercial pressure sensor with quartz element. The signal of the pressure sensor was acquired up to 400ºC.

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