TiN_x thin films are prepared by a r.f. reactive ion plating method. Structures and electrical and optical properties of them are investigated. Deposition conditions of the films and annealing effects in vacuum are discussed. As the depositionrate decreases, the structure of the film changes from a solid-solution of Ti and N to a TiN compound. After annealing, about a fivefold to tenfold increase of the resistivity of the TiN_x films is observed. Temperature coefficients of the resistivity are varied from positive to negative, and its value increases as increase of the resistivity. Hall coefficients of the solid-solution films of Ti and N are positive. On the other hand, those of the TiN films become negative. After annealing, the carrier density of the solid-solution film of Ti and N becomes tem-perature dependent and the activation energy is about 19 meV. Colors of the TiN_x films depend on the deposition conditions and the films with gold, silver or violet color are obtained. After annealing, silver or violet color changes to gold which is characteristic color of pure TiN.

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Recently, far-infrared heatings have been interested in the field of heating, because they are useful, not so expensive, and have excellent heating efficiency. The oxide-ceramics are generally used for the far-infrared radiation materials by their excellent radiation and heat-resisting properties.
The far-infrared properties on some single oxide-crystals were measured at the wavelength range between 5μm to 25μm, at the surface temperature of 150 and 250°C. Those radiation properties were compared with the far-infrared radiation properties of the oxide-ceramics, and it was found that there were little discrepancy between the both properties.

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The cathodeluminescence (CL) properties of semiconductor bariumtitanate ceramics quenched at any sintering stage and applied voltage have been investigated.
Oxygen vacancies (blight area) in grains were created at early sintering stage. High concentration of Ba vacancies of grainboundary diffuse towards inner grain.
The reoxidation occured in the region from middle sintering stage to tinal one. The phenomenon is explained by the peak height of CL spectra. The peak height of CL spectra is related with specific resistance.
The domain walls obserbed by CL image disappear when the temperature rises under the applied voltage condition. But there is no change for the grain boundary.

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The designing and the powder metallurgical fabrication of molybdenum/zirco nia functionally gradient material for high temperature use has been described. The process includes the precise control of the sintering rates of metal and ceramic powder mixtures, the determination of the thermal expansion coefficients and theelastic moduli, as well as the breaking strenght of the two phase composites, and the designing of the optimum compositional distribution on the basis of the finite element analysis of thermal stress, which is generated upon cooling from sintering temperature.
According to the optimum compositional gradient the sintered compact of the functionally gradient material of the combination of molybdenum and zirconia was successfully fabricated. The synthetic composite showed uniform structural transition from metal to ceramic phase and included neither thermal-stress crack nor microstructural defects.

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SiO₂-TiO₂ porous glasses were prepared from SiO₂-TiO₂-B₂O₃-Na₂O glasses by means of the phase separation method. In the porous glasses, TiO₂ existed as glass phase with SiO₂ at lower phase separation temperature and as crystal phase of anatase or rutile at higher temperature. The pore size of porous glasses increased with increase of phase separation temperature and time, but it decreased by reheat treatment of porous glasses.

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Dependence of the reaction rate on the particle size ratio as well as the molar ratio, which was unable to be interpreted by the Jander model, is explained by introducing the exactly evaluated number of contact points. In particular, a quasisteady state analysis shows that the reaction rate per contact point at an early stage in relation to the size ratio of both components depends clearly upon the diffusion mechanism i. e., unidirectional or counter diffusion. Experimental data confirm the above theory, from which possibility of determining the diffusing component is discussed for a specific solid-solid reaction system.

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One caking and four noncaking coals were hydropyrolyzed rapidly in a freefalltype pyrolyzer which enabled coal particles to be heated in an order of 10⁴°C/sec and accomplished a good extent of recovery of liquid products. Changeswere observed in volatile yield, caking property, and internal surface area withsuch short treatment times from ca. 0.1 to 0.6 sec. Devolatilization behavior waskinetically simulated assuming a hydropyrolysis mechanism.

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Decay behavior of photostimulated exoelectron emission (PSEE) from aluminumsurface after abrasion was examined under air and argon in a gas-tightchamber. Detection of PSEE was conducted by picoammeter under irradiationof an ultraviolet light. Wavelength of the light was controlled by a UV-filter.Effects of water and oxygen on the decay behavior were tested. Water and oxygenin argon were removed by a liquid oxygen trap and a furnace with titanium tips, respectively. Oxygen partial pressure was monitored continuously by a solid stateelectrolyte of zirconia. Decay process of PSEE under atmospheric pressure wasnot expressed by a simple kinetic equation. Although oxygen, impurity in argon, did not affect the decay behavior, water in air and argon promoted decay of PSEEleaving irreversible change on aluminum surface.

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The stability of a geothermal reservoir on an oblique fault plane in a hot dryrock during extraction of heat is considered The analys is is made on the basisof the two-dimensional theory of quasi-static thermoelasticity. By numericalcalculations, the upper and lower critical fluid pressures being necessary for thereservoir stability are determined. As a result, it is found that the domain ofstable fluid pressure extends with increasingo ftime.

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In examining powder materials for solid product especially in high technology, 1) the elucidation of the hierarchy between powder materials and each particlelevel (electoron or molecular) and 2) thermophysical one of powder level arepointed out to be the most fundamental two problems in developing functionalmaterials. That is, powder materials should be discussed thermophysically justlike electron or molecular particle system. In order to discuss this point, two typicalpowder behaviours of tapping operation and shearing slip are noticed thermophysically. As a result, two thermophysical conceptions of powder distribution function and chemical potential are, fundamentally and experimentally, shown to be sufficiently effective for powder behaviours above. And also thermophysicalequilibrium is exhibited fundamentally to be able to describe thefromation mechanism of powder inhomogeneity by shearing.

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