Alumina bicrystals were fabricated by a diffusion bonding technique in air to obtain the pyramidal sigma-13 twin grain boundaries. We observed the grain boundary structures by high-resolution transmission electron microscopy(HREM). And also we performed first principle calculation for the atomic structures and static lattice calculation for segregation behavior of Lu. As a result, it was supposed that Lu segregate specific site at grain boundary core region.

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Interface strength, chemical bonding, and O-K ELNES of Cu/Al2O3(0001) interface was calculated by using the first principles band structure calculations. The origin of the weakeness of the on-top configuration can be ascribed to be the strong anti-bonding interaction between the interfacial oxygen and the 2nd near neighbor Cu. It was found that the pre-peak feature of O-K ELNES is related to the chemical bonding of the interface.

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Effects of Y2O3-CaO addition having composition of Ca12Al14O33 on low temperature sintering behavior and thermal conductivity of AlN ceramics were investigated by measurements of shrinkage, density, identifying phases by XRD, AlN crystal lattice c and thermal conductivity by the Laser Flash method. Density of samples with borides are higher than that of sample added without the borides sintered at 1550 -1650C for 2h. AlN crystal lattice c expanded at lower temperature in the case with borides sintered for 2h. Thermal conductivities of the samples with borides are higher than the sample added just Y2O3-CaO sintered for 4h.

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According to both the first principle and materials chemistry, an innovative method for fabricating of the Ca1-xSrxTiO3 ceramics was investigated. Ca1-xSrxTiO3 was sintered at temperatures as low as 980 Degree C by adding 1.0 wt % Li2Si2O5 without forming a grain boundary phase. It was considered that the sintering was promoted by self-accelerated diffusion due to the formation of point defects caused by doping with Li2Si2O5. Consequently, a new concept of non-stoichiometrically activated sintering, which is enhanced by point defects without the help of a grain boundary phase, is systematically studied for the first time in the Ca1-xSrxTiO3- Li2Si2O5 system.

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The new type of hermetically sealed high intensity discharge lamp, made of Mo-SiO2 functionally graded material (FGM) were investigated to accomplish the highly reliability. As a result of investigations, we found that Mo-SiO2 FGM was successfully fabricated using combined sedimentation and pressurized slip casting method with perfect grading from the conductive part (Mo-rich phase) to the sealing part (SiO2-rich phase) and attained the concept 'Unify the thermal expansion behavior of Lamps'. This made it possible to produce various features of lamps, for example, tolerates large numbers of heat cycles, or no explosion of lamp takes place.

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Influence of particle size distributions with various geometrical standard deviations on platelike alumina grain growth in submicron alumina powder compacts was investigated. Nine kinds of alumina powders doped Si/Al=500ppm and Ca/Al=50ppm with same median diameter (D=530nm) and different geometrical standard deviations (Shigma=1.2-2.0) in lognormal particle size distributions were prepared. Relative densities of sintered bodies increased with decreasing Shigma. Platelike grains were observed in over 1.4 of shigma compacts. Number and size of platelike grain increased with increasing shigma.

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SiC of 800 nm diameter, SiC of 30 nm diameter and Al2O3 of 200 nm diameter were mixed in a 0.05-0.6M-Y(NO3)3 solution. The SiC compact consolidated by filtration was hot-pressed at 1950oC in an Ar atmosphere. Addition of 30 nm SiC and alumina (1.2 vol%) to 800 nm SiC with Y2O3 enhanced the flexural strength to 1070-1080 MPa. The fracture toughness of the SiC decreased with increasing Y2O3 content.

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Si3N4/5-wt% carbon nano/nano-composite was successfully fabricated for the first time by high-energy mechanical milling followed by spark plasma sintering. The milling promoted the amorphization of starting powders; most of the carbon particles were transformed into nano-size and embedded in the amorphous phase. This, combined with low sintering temperature and rapid densification rate, prevented the reactions between carbon and other starting powders, leading to a nano/nano composite microstructure. The nano-sized carbon grains with average diameter of about 10 nm were homogeneously dispersed in nano-sized (about 70 nm) silicon nitride grain boundaries. The hardness of obtained nano-ceramics is comparable with that of conventional silicon nitride, whereas Youngs modulus is significantly decreased.

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The questionnaire survey concerning the current status of the creativity development classes in Tokyo Institute of Technology had been done. Percentages of the creativity development classes in the whole classes were 6.0 and 2.4 % for undergraduate school and graduate school, respectively. Most popular teaching method was discussion-oriented teaching. The method to develop the creativity during experiment was next popular method for undergraduate school, but the design-oriented classes for graduate school. The satisfaction survey of the students had attended to the creativity development classes showed the delicate differences by the lecture styles and the disciplines.

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Phosphors of M2Si5N8:Eu2+(M=Ca,Sr) were synthesized by using the graphite powder as a reductant ("Carbothermal Reduction and Nitrogenation Method") and the luminescence properties were characterized for the applicable use as the red phosphor for white LEDs.

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The development of white-light LED in near-UV region with phosphors is one of the significant topics recently. However, the efficiency improvement at red interval is specially emphasized. In this study, SiO3-based phosphors doped by Eu3+ was synthesized via sol-gel method. Effects of calcinations conditions, contents of Eu3+ on microstructure and photoluminescence ( PL ) properties by 383nm pmping source of synthesized phosphors were investigated. The results shows the absorption or exaction wavelength of MgSiO3:Eu3+ phosphors is between 350~420nm as the emission peak is at 613nm. Relative emission intensity of MgSiO3:Eu3+ phosphors increased with the increase of the holding time for calcinations and the contents of Eu3+ doped, decreased after grinding process.

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Bio-imaging is a key technology for prevention, diagnosis and therapy in medical science and technology. One of the most important problem among current ones for the bio-imaging is breaching of organic phosphor. To prevent the breaching and the reduction of light scattering, inorganic upconversion phosphor excitable by infrared light is investigated to be adopted into the bio-system. As the upconversion phosphor, Er doped Y2O3 was nominated. To achieve the adoption and dispersion of the phosphor, Y2O3 nano-particles successfully adsorbed poly acrylic acid and acetal-PEG-block-PAMA on the surface with a layer-by-layer structure..

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Highly crystalline NixZnyCozFe3-x-y-zO4-δ films (x=0.1-0.4, y=0.2-0.8, z=0.02-0.03) were prepared by spin spray technique at a very low temperature of 900C without any post annealing. The magnetic properties like Hc, Ms and permeability were found to depend widely on the compositional variation of the films. A small addition of Co in the film was found to help in obtaining a high permeability. A maximum real permeability of about 180 and resonance frequency of 80 MHz were obtained for Ni0.17Zn0.6Co0.02Fe2.2O4-δ film.

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