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The ability of carbon to form a plethora of compounds through C-C bonding is unique, however, bonding is confined to s and p electrons. Metallic elements on the other hand offer a greater versatility in covalent M-M bonding as they provide s, p, d and f electrons besides the fact that the majority of elements is metallic. The materials aspect of metal-rich phases is ample. A few structure-property relations will be addressed, e.g. magnetic order and disorder in low-dimensional and frustrated systems, giant magnetoresistance, superconductivity and low work function.

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Complex metal oxides are normally synthesized by high-temperature ceramic method. As a result, an oxygen coordination form around a metal is restricted to those which are thermodynamically stable. We recently obtained SrFeO2 by extracting 1/3 of oxygen atoms from the Perovskite precursor phase SrFeO3, by using low temperautre hydride reduction (Nature 450, 1072 (2007)). SrFeO2 is isostructural with the high Tc cuprate SrCuO2, and has an unsusual square-planar coordination. In my talk, reaction mechanism, electronic state, and magnetic properties will be reviewed.

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As a way for improving the cathode performance of IT-SOFC, catalyst infiltration technique into the existing (ready-made) electrodes was studied; one is a modified LSM-YSZ electrode in which particles of oxide ion conductors are distributed in nano-size, and the other is the LSCF electrode in which small silver particles are distributed. In both cases, the significant improvement of the electrode performance was observed.

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ADMIRE PROJECT at Institute of Advanced Energy (IAE) in Kyoto University is a MEXT supported program for 5 years to delivery of science and technology from Kyoto University to companies. development of excellent total performance SiC fiber-reinforced SiC matrix (SiC/SiC) composite components will be presented as a part of accomplishment though ADMIRE project. Tailoring of raw materials and selection of fabrication temperature/applied stress are emphasized as the important technical key issues. MUSTER (Multi-scale testing and evaluation research), such as FE-TEM, TEM, FE-SEM and hot-pressing equipment will provide the special innovation on fusion and fission materials research and development (R & D).

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Micro-damage will be generated in porous ceramic materials when compression processing is preformed on it. A non-linear relationship between stress and strain containing information of micro-damage generating and evolution is usually available, which is called strain-stress curve. This research presents a theory to deduce and gain the micro-damage generating and evolution process from the stress-strain curve. The probability density function of damage strain is calculated according to this theory and contrasted with the acoustic emission (AE) signal and they fit well with each other. Moreover, the damage principle of porous ceramic material is discussed based on this theory.

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Ultrahigh porous silicon carbide (SiC) with oriented micrometer-sized cells was prepared by novel gelcasting method. Gelation agent, water and SiC powder were mixed and gelled. The resultant gel obtained was frozen, dried, degreased at 600C and sintered at 1800C for 2hr. The porous SiC showed ultra highly porosity around 87-93%. SEM observations showed the microstructure of orderly uni-directionally oriented micrometer-sized cell. The cell in the cross section had the size around 40um in the diameter and the wall thickness of 5-15um. Number of cell was about 500-800cells/mm2. The pore size measured by Hg porosimetry showed a bimodal distribution due to cell and space among particles.

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Safety Gears, which stop elevators by mechanical braking in emergency states, are indispensable to all elevators. Shoes in the safety gears are pressed against the guide rails of the elevators to brake. Consequently, the temperature of the shoes rises with the speed of elevators. Toshiba developed world's fastest elevator running at the speed of 1010 m/min. In this speed, the temperature of the shoes was estimated to be over 1000 C by the friction, which implied that the conventional metal shoes could not be used. Accordingly, the development of ceramic shoes was essential. Based on many friction data of various ceramics, ceramic composites were designed to achieve high thermal shook resistance and high friction coefficient at high temperatures and the world's fastest elevator was achieved. This elevator is running in the Taipei 101 building.

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The nitridation behavior of silicon powder added with three kinds of particle size ZrO₂ was studied in order to assess the nitridation behaviour of silicon on the formation of reaction bonded silicon nitride, using high purity silicon powder and monoclinic zirconia as starting materials. Thermogravimetric analysis revealed that the addition of ZrO₂ to Si powder reduced the temperature of the main nitridation reaction, and increased the amount of silicon converted to silicon nitride at a given temperature.

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The chemically modified silica gel was prepared using tetraethoxysilane, methyltrimethoxysilane and n-propyltriethoxysilane. The adsorption isotherms for nitrogen gas (at 77 K), water vapor (at 298 K) and toluene vapor (at 298 K) of chemically modified silica gel were measured. The effects of chemically modified compound on the water and toluene vapor adsorption properties were investigated.

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