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This study was investigated for the thermal conductivity measurement of grains of the very-high-thermal-conductivity aluminum nitride ceramic by thermo-reflectance technique. AlN ceramic with a thermal conductivity value of 272 W/m∙K was fabricated by firing at 1900 ^oC with sintering aid of 1 mol% Y₂O₃ under a reducing N₂ atmosphere for 100h.

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Fully dense multi-wall carbon nanotube (MWCNT)-silica-based nanocomposites with MWCNT contents ranging from 5 to 10 vol.% have been processed by spark plasma sintering (SPS), and their thermal conductivities were measured at room temperature by laser flash technique. The thermal conductivity of the nanocomposites was improved due to incorporation of MWCNT compared with pure SiO2 matrix. The improvement in thermal conductivity was enhanced with increasing MWCNT. In addition, the increases in both sintering temperature and time enhanced heat transport in the nanocomposites. A maximum conductivity of 4.1 W/m.K was obtained for 10 vol.% MWCNT nanocomposites sintered at 1050°C for 10 min.

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In order to investigate effects of rare earth metals-doping for Ca on thermoelectric properties of layered cobalt oxide Ca3Co4O9, a series of (Ca,Re)3Co4O9 polycrystalline samples (Re = rare earth metals such as Dy, Ho, Er and Lu) are prepared and their high-temperature thermoelectric properties are systematically investigated.

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Thermal shock resistances of Sc-stablized zirconia as used for the elecrolyte of Solid Oxide Fuel Cell (SOFC) were evaluated by infrared radiation heating (IRH) technique. Thermal shock strength of thin disk specimens (t=0.15mm) fabricated by pressureless sintering or post-HIP were estimated experimentally and theoretically using the IRH technique. Temperature dependence of thermal properties of the materials was taken into account for the temperature and the thermal stress analysis. Experimental values of thermal shock strength decreased with the contet of Sc and increased with HIPed time.

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SiC nano-sized powder with high specific surface area is potentially of considerable interest to form fully dense SiC ceramics at lower sintering conditions (temperature/pressure). Surface structure of six kinds of commercially available SiC nano-sized powders produced by three different venders was analyzed in detail by X-ray photoelectron spectroscopy (XPS). Surface structure of nano-sized powders included one of three impurity phases: (1) free carbon, (2) silica and (3) silicon oxycarbide. Furthermore, the influence of surface structure by XPS was systematically investigated on basic powder characteristics, such as chemical composition, morphology, particle density and primary particle size. It was revealed that the basic powder characteristics had a close relationship to the surface structure of nano-sized powder each impurity.

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Al-Si arrangement was investigated by molecular dynamics simulation. Under 5 GPa of tension, higher Al-Si ordering glass showed longer fracture time and larger fracture strain compared to lower ordering glass. Because of higher homogeneous distribution of Al ions in the highly ordered glass, Al ions were easily re-combined with non-bridging oxygen ions after Al-O bonds were broken.

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Correlation between basicity and structure of borosilicate glass was investigated based on a regression analysis, where the fraction of four-fold borons (B4) was expressed by glass basicity,  as an explanatory variable. When B4 fraction against the sum of Si content multiplied by a coefficient f and B content, B4/(B+Sif ) was used as an induced variable, the regression formula given as a function of basicity showed high correlation coefficient > 0.8.

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Magnetite, Fe₃O₄, was deposited on the layer-by-layer (LbL) assembled polyelectrolyte multilayer films by the aqueous solution process. Fe₃O₄ particles were deposited on Pd catalysts which were adsorbed to the -NH₂-terminated surface of LbL multilayer, in an aqueous solution containing iron nitrate and dimethylamine-borane. Pd colloid catalyst particles were adhered to the amino group of polyelectrolyte by electrostatic interaction. Furthermore, hybrid hollow capsules composed with polyelectrolyte multilayer and Fe₃O₄ were also successfully fabricated via the aqueous solution process combined with the colloid template technique.

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In this study, we have proposed a technique to fabricate a thin film of smectite using EPD, which is a simple ceramic processing carried out under an ambient condition. The smectite is an exfoliated flat particle which has a negative charge in a basic aqueous solution. With applying a DC voltage between two electrodes in the solution, the smectite particles move to the positive electrode, on which a layer is eventually formed. The surface and cross-section of stacked smectite layers were observed and characterized by SEM with EDS. The thickness of the layers increased with increasing the applied voltage.

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Layered double hydroxides (LDHs) are well-known as hydrotalcite-like clays, and have been studied over the past several decade since they have large potentials for the applications of anion-exchanger, catalysts, and immobilization hosts of biological materials by intercalation of various anionic matters into the layers. Most of studies used powder samples of LDH. For the application of optical and electronic devices, coatings of LDHs on substrates should be much suitable. Here, LDH coating films were directly prepared by the aqueous solution process using sol-gel-derived Al₂O₃ gel films. This process achieved synthesis LDH coatings at low temperature less than 100 °C. In this study, we focused on Zn-Al LDH coating and investigated the effects of concentration, temperature, and pH of zinc acetate solution and reaction time for the formation of LDH from Al₂O₃ gel films.

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