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Although conversion of coal fly ash to zeolitic materials have been performed, using its main elements such as Si and Al, unburned carbon of 10-20 mass% in the coal fly ash has not been used. In this study, we tried to prepare composite materials with zeolite and activated carbon, noting main elements and unburned carbon in the coal fly ash.

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The recycling technology of water purification sludge using hydrothermal treatment was investigated. The sludge was mixed with 0-20mass% of Ca(OH)₂. The mixtures were formed by uniaxial pressing and hydrothermally treated under saturated steam pressure at 220^oC for 10 h. The flexural strength of the specimens increased with amount of added Ca(OH)₂ to 5mass% and reached the maximum value of 13.0MPa. The nanostructures formed through the hydrothermal treatment influenced on the strength development. TEM-EDX results showed the nanostructures consisted of mainly SiO₂ and Al₂O₃ with Ca/(Al+Si)=0.02 and Al/(Al+Si)=0.57. Nitrogen gas adsorption porosimetry showed the specimen had 4-7 nm mesopores. The high specific surface area of 157m²/g suggests an application as a self-humidity conditioning material.

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Hydrogen is regarded as the new generation energy carrier. Hydrogen is mainly made by steam reforming of methane at high temperature. It is well known that the efficiency of this reaction could be improved by selectively separating out hydrogen from the reactor. With this purpose, we have developed hydrogen separation membranes with Si-N ceramics, which can be used at high temperatures. Usually, ceramic membrane is supported by porous ceramic substrates. Important features for substrates are sharp pore size distribution and porosity. So we tried to control the pore size distribution and porosity of porous silicon nitride substrates by reaction sintering.

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Hydrogen is mainly made by steam methane-reforming at high temperature. The efficiency of this reaction could be improved by selectively separating out hydrogen from the reactor. We have succeeded in production of molecular sieve membranes starting from Si-N organic precursor, polysilazane. The processing of microporous membranes were carried out by the controlled pyrolysis of polysilazane. High-temperature gas permeation studies were performed using the membranes and H2/N2 selectivity values above 100 were measured.

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The most optimum conditions of hydrolysis for preparation of raw powder of titania was studied. The Ti(OH)4 precipitated from TiCl4-HCl solution by adding NH4OH, then filtered and washed, adjusted the amount of water contained in Ti(OH)4 cake by a centrifuge. Slurries were added conc. HCl to adjust Cl-/Ti4+ ratio. The slurry was heated at 40C for 24 hours. At Cl-/Ti4+ ratio=1 synthesis ratio was 98%, specific surface area was 83 m2/g, and the relative density of >98% was attained by firing at 950C for 3 hours.

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The grain morphology and sinterability of zirconia formed from concentrated ZrOCl2 solutions was studied. Sealed double structured vessels, in which a reactive alumina powder packed in the outer vessel, were used. The zirconia powder composed of spherical aggregates of 1.0 micro-meter in diameter was obtained by hydrolysis of the concentrated solution. The diameter of the aggregates decreased with adding some other chloride hydrates. The relative density of 94% was attained by firing at 1350C for 2 hours using aggregates of 0.5 micro-meter in diameter with 3 mol% Y2O3 added.

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Nanosheets of crystalline tin dioxide with ca. 20 nm in thickness were grown on a glass substrate at 60 degree C in aqueous solution of tin difluoride containing urea. The c axis of the crystal was perpendicular to the surface covered with fluorine. Cellular porous films were prepared though further growth of the nanosheets on the substrate.

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Layered polysilicate octosilicate (Na₈[Si₃₂O₆₄(OH)₈‚32H₂O], Na-Oct) was modified with methanol as a course of our study on nanoscaled inorganic-organic hybrids. The interlayer sodium ions were exchanged with protons by acid treatment and the H-type octosilicate was allowed to reat with methanol to form methoxy-modified octosilicate. The immobilization of methoxy groups onto the interlayer silanol groups was confirmed by XRD, ¹³C CP/MAS NMR,and TG-DTA.

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A silica-like layer was grafted on polymer surface and self-assembled monolayers (SAMs) were fabricated on the polymer substrate. The SAMs were modified into templates and micropattern of functional membranes was deposited on the substrate. To suppress the undesired contaminating, barrier effect was employed by using shielding reagent. Super site-selective micropattern of functional membranes was successfully obtained on polymer substrate.

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Energy conversion using solid state ionic conductor such as fuel cell (SOFC) is focusing to future technology. Especially, low temperature drive and scale down are important on SOFC applications. For the purpose of developing ionic conductive micro-tube reactor, we are carried out preparing Gd doped CeO2 micro-tube by solution chemical processing.

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Production of carbon nanoparticles from benzene-derivatives in an ultrasound field have been studied. In the presence of metal particles, such as zinc, nickle, cobalt, or iron, the raw material liquid showed a marked darkning due to the occurrence of polymerization. We confirmed nanotubes, flake-like particles, amorphous and so on by SEM and TEM observations.

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We have been studied on the inorganic-organic hybridized luminescent material and reported that GaOOH modified with organic polymer had a good luminescence property. In this study, we examined the experimental conditions for the synthesis of GaOOH modified with polyacrylate (PAA) by several methods. The GaOOH-PAA hybrid material with good luminescence property was successfully synthesized by the addition of 20 mass percent PAA. It was also confirmed that the chemical bond between GaOOH and PAA is required for electron transfer.

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Silver/gamma alumina catalyst prepared by the solvothermal process showed lower active temperature and higher conversion of NO.It can be attributed to the relatively uniform distribution of silver on the support.

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A development of micro patterning technique is very important to create new electrical or optical devices. It is well known that materials consisting of three dimensionally ordered microspheres, which is so-called colloidal crystal or artificial opal, show an interesting optical nature due to the Bragg diffraction of a light. The materials have a high potential for micro optical device applications. In this report, we fabricated the micro patterning consisting of three dimensionally ordered monodisperse polystyrene spherical particles by a micro electrophoretic deposition method using a micro printed electrode.

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Macroporous zirconia ceramics with a well-ordered pore structure and high surface area have attracted interest due to their unique catalytic properties. The method using coated PS (polystyrene) particles as templates and then removing PS by heat treatment was developed on preparing silica and other macroporous materials. In the present research, a simple deposition method for the production of zirconia coating on polystyrene particles had been performed. SEM and TEM micrographics show that the zirconia precursor had been evenly coated on polystyrene particles.

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Hollow calcium carbonate might find a variety of uses in catalysis, pharmaceutical and agrochemical as controlled release particles. For these applications, it is required to dope fine functional particles into the hollow particle. In the previous study, hollow calcium carbonates were successfully synthesized by CO₂ bubbling in aqueous solution of calcium chloride with the presence of ammonia at room temperature. The precipitation was carried out by controlling the pH, temperature and CO₂ flow rate. In this method, CO₂ bubbles beside as reactant, they also have a role as template of hollow particle formation. Obtained hollow particle was mainly vaterite phase and spheres morphology in diameter about 1-7 micrometer. The aim of the present study is to develop the doping method of the fine powder into hollow calcium carbonate.

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