A Probabilistic model is used to derive the tension-softening relation for short-fiber-reinforced composites. By the use of the tension-softening relation, the fracture energy and the load-displacement relation can be obtained. We applied it to a short-fiber-reinforced SMC composite at low temperature. From the results, we realized quantitatively that the fracture energy increased and the SMC composite was strengthened at low temperature.

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The result of our investigation whether it is possible or not to anticipate the electrical breakdown of magnet coils used in magnet relays is reported. We employed the method of counting partial discharge pulses. Magnet relays used in various power facilities sometimes come to brekdown. It is faborable if we anticipate the failure of magnet coils beforehand. We examined the current pulse characteristics of partial discharges. From our experiment and statistical treatment of the data we concluded that the discharge pulse counting method is useful for anticipating the failure of magnet coils used in power systems.

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Vapour pressures of PbS in the pure PbS, FeS-PbS and Cu₂S-PbS systems were measured by the transportation method within a temperature range from 1115 to 1170°C, and the activities of the components in the two binary systems were calculated. Also, the phase diagrams of the FeS-PbS and Cu₂S-PbS systems were determined by the DTA method to compare with the experimental date of activities.
The experimental results obtained are summarized as follows:
(1) The vapour pressure of PbS in the range of 1115-117°C was given as: log P_PbS/atm=-9193/T+5.69
and the boiling point and heat of vaporization of PbS calculated from the equation of vapour pressure were 1341°C and 42. 0kcal/mol, respectively.
(2) The activities of FeS and PbS in the FeS-PbS system at 1150°C exhibited nearly the ideal behavior, and the calculated activities from the phase diagram supposing a regular solution agreed with the experimental results.
(3) The activities of Cu₂S and PbS in the Cu₂S-PbS system in the range of 1130-1170°C showed negative deviation from the Raoult's law, and they were little changed by differences in temperature. The activity coefficients at the infinite dilution of the components in the system were estimated 0.04 and 0.22 for Cu₂S and PbS at 1150°C, respectivery.

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Recently, The ceramics which show interesting electric, magnetic and optic functions are used and taken notice in various fields. Then, electro ceramics manufacturing process becomes important in industry. The electoro ceramics manufacturing process consists of various kinds of unit operation such as weighing. mixing, crushing, firing and so on. Electrical properties of electro ceramics as final product depend upon each unit operation. However, the thermophysical relation between them has not yet been elucidated up to now.
Then in this paper, the relation between intermediate or final material properties and the operation conditions of electro ceramics maunfacturing process is discussed from the view point of thermophysics. And it can be point out that thermophysical three concepts such as entropy energy, free energy and carnot cycle can be effectively applied to elucidate the relation mention above electro ceramics manufacturing process.

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The high temperature corrosion of Ni with molten carbonates coating was studied under 33%O₂-67%CO₂ atmosphere at the temperature range 873K-1073K.
The corrosion behavior depended on the impurities of Ni specimen. For 99.997% Ni the hot corrosion occurred below 1023K. For 99.7% Ni that contained 43 ppm Fe the hot corrosion took place below 973K. However, for 99.7% Ni that contained more than 335 ppm Fe the severe corrosion could not be obser ved at any temperature.
The hot corrosion was closely related to the solubility of NiO in the carbonate melt. The iron impurity in Ni might suppress the solubility of NiO.

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Recently it is expected that the technology using magnetic tracer will enable to measure subsurface fractures. The magnetic tracer to be used in the above case is a suspension of magnetic particles and it must be thermally stable and possess high initial magnetic permeability.
We measured the initial magnetic permeability of various magnetic particle assemblies such as ferrite and metal materials. Relationship between initial magnetic permeability of particle assembly and of bulk material can be shown experimentally. Function of initial magnetic permeability against volume fraction was simulated using Ollendorf's equation, however its equation was not enough to explain the experimental results. This fact suggests that the effect of static magnetic interaction between particles could not be evaluated sufficiently in this condition. The initial magnetic permeability of particle assembly was nearly constant up to the Curie temperature. Though the initial magnetic permeability of flake shaped sendust decreased largely by the hydrothermal treatment, the ones of other metal materials decreased a little and of ferrite materials remained unchanged. Taking account of these results, we conclude that iron particle is suitable candidate for the tracer.

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Temperature dependency of relative permeability of oil and water, irreducible water saturation, and residual oil saturation were measured for sandpack of silica and limestone. And, on the basis of the results obtained, mechanisms of oil displacement in the forward in-situ combustion process were discussed.
Results are summarized as follows.
(1) The relative permeability of both oil and water decreases with increasing temperature for both silica and limestone sandpacks.
(2) The relative permeability of oil for silica sandpack is higher than that for limestone sandpack, though the relative permeability of water for both silica and limestone sandpacks did not show the difference.
(3) The irreducible water saturation increases and the residual oil saturation decreases with increasing temperature for both silica and limestone sandpacks. In comparison of residual oil saturation for both sandpacks, that for limestone sandpacks is higher, while the irreducible weter saturation for silica sandpack is higher than that for limestone sandpack.
(4) The mobility of oil in the steam bank is higher than that in the virgin zone because of the higher temperature. However, it does not increase drastically as expected from the temperature dependency of oil viscosity because of the counter nature of oil viscosity and relative permeability of oil with temperature.
(5) The wide portion of oil bank is not heated up by the heat liberated by combustion, so that the mobility of oil in the oil bank is little improved. However, the movable oil increases due to the nature of decreasing residual oil saturation with increasing temperature because of the temperature increase at the back part of the oil bank. This effect may result in the higher oil recovery.

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Amorphous metallic Ni ultrafine particles were synthesized in aqueous or nonaqueous media with a reducing agent, NaBH₄, by the liquid-phase reduction method. Their size was affected by the synthesis temperature and drop rate of the reducing agent addition. Because the reduction rate of Ni cation into metal was very high, under the condition that the supply of a reducing agent was a rate-determining step a particles size was considerably promoted. With increasing in temperature the size was decreased, because the reduction rate was increased and nuclei numbers were enlarged. As in aqueous media at high temperature the decomposition rate of a reducing agent exceeded that of the reduction into metal, no metallic Ni ultrafine particles were obtained. The size of Ni particles synthesized in 2-propanol as a solvent at 82°C, the boiling point, was 50nm in volume average. The particles were found as a catalyst highly active for 1-octene hydrogenation.It is to be noted that cyclohexene was predominantly obtained in the benzene hydrogenation with using the particles. However, they didn't play a role of a hydrogenation catalyst but provided hydrogen derived from a reducing agent in preparation to benzene; the reaction continued until the complete consumption of hydrogen in a particle.

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When partial discharge (PD) was measured with the conventional pulse method, it sometimes apparently disappeared. However, it turned out that the PD did not actually disappear, but only became a large number of very small partial discharges known as swarming pulsive microdischarges (SPMD). After this silent stage, detectable PD appeared again, leading to final breakdown. Since SPMD are missed in the conventional PD pulse detection method, it is necessary to pay careful attention to SPMD in terms of insulation diagnosis. We developed a personal-computer-aided partial discharge analyzing system (CAP DAS) for SPMD measurement. Based on the measurement with this system, a new PD parameter, the SPMD ratio, was introduced for quantitative analysis of SPMD. Using the developed system and the new parameter, partial discharge characteristics of the modified CIGRE Method-II (CM-II) specimen were studied to clarify the factors affecting the occurrence of SPMD. It became clear that void surface roughness caused by the PD degradation is found to be one of main factors. Further the amplitude and the frequency of the applied voltage also affect the occurrence of SPMD.

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Zinc oxide single crystals of high purity have been grown by hydrothermal method under a partial pressure of oxygen, using a platinum-lined autoclave and ultra-pure reagents. The stoichiometry of grown crystals was investigated by employing coulometric technique to detect a small deviation in the stoichiometric constituent towards Zn_1+xO. The concentration of the excess Zn atoms was accurately determined from 0.8 to 1.7 ppm and the electrical resistivity of the as-grown grown crystals measured as of the order of 10⁸Ω-cm.

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It is very important to measure the electric field-strength in an insulator to understand a mechanism of dielectric breakdown. Recently, the development of the optoelectronics and the computer has been helped the measurement of electric field-strength in a liquid dielectric by optical method using the Kerr effect The sample liquid was nitrobenzene which has the Kerr constant of 3.62×10^-12m/V². Two test cells were used one was a brass coaxial cylindrical cell with two glass windows for the measurement of two-dimensional electric field vector and the other was a Teflon rectangular cell for the measurement of three-dimensional electric field vector.
The He-Ne laser was used for a light source. The negative high voltage pulse was applied to the electrodes which were displaced in nitrobenzene. The intensity of the light transmitted through out the analyzer was measured with a photodiode. The electric field vector was calculated from the intensity of the measured light by the computer.

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Anlaysis on energy reflection of plane waves impinging on an inhomogeneous multi-layer is presented. The variation of acoustic impedance through the individual inhomogeneous layer is defined by a linear function of the thickness coordinate z. Closed form analytical solutions of the coefficient of energy reflection and transmission are obtained for the normal incidence to show fundamental but reliable results. The discontinuity of acoustic impedance at interfaces affects dominantly on energy reflection. Then the explanation of the effect has been systematically with the variation of impedance.
It is possible to show that the model of linear inhomogeneous layer is equivalent to a stacked layer made of 12 homogeneous layers. The analytical model may be available effectively to a transitional layer of deteriorated bonding interface, and a layer of functionally gradient material and so forth.

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Recent improvements in idustrial technologies require more critical purification of raw materials to obtain the optimum charachteristics of final products.
It has brought up new technologies of material purification, which includes newly developed rare earth permanent magnetic materials and improved magnetic separation technologies. The paper will discuss possibilities of applying rear eath magnetic separation to those area where permanent magnetic separation has been considered impractical or impossible. The paper will also introduce most recent applications of purifying industrial minerals or maetalic minnerals using those newly developped magnetic separation method.

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