In the previous paper, the authors have theoretically introduced a judgment method to determine the diffusing component of a specific solid-solid reaction system, based on the dependence of the reaction rate upon particle size ratio. The method is actually applied to some reaction systems in the present paper, and the results agree well with the observed results.
Furthermore, a simple prediction method without experiment is sought, using only the physical properties of reacting components; e. g., the ionic radius and the atomic coordination number. The present method is satisfactorily confirmed by a lot of observations so far reported, with the probability of 91%.

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The prediction of the stress distribution in the powder bed is important for the design of the storage vessel and the unit operation of the powder. We calculated the stress distributions in a plane stress field by using the constitutive equation of powder based on the plastic potential and Coulomb-Mohr criteria, and the incremental finite element method.
We also measured the wall stress distributions and compared them with the calculated results. They agree with each other in the horizontal stress distribution of the side wall as well as in the vertical stress of the bottom. Hence, the constitutive equation and our simulation method are reasonable and would be useful for the design of the powder storage vessel.

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Recently, ceramics technology has been developed as electronic parts such as capacitors, PTC, variable resistors and so on. But, there are not so many for the reports related to twodimensional application like p-n junction using ceramic semiconductors.
In this paper, it has been carried out the investigation for the preparation of p-n junction using ceramic semiconductors. The samples were prepared by means of following two methods: (1) p-n junction contacted by spring force using blocks of ceramic semiconductors, and (2) p-n junction of the thick film prepared by coating. We used NiO as P-type, and PTC as N-type. This paper describes a possibility of application to the capacitor for p-n junction prepared by the ceramic semiconductors.

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The electrical breakdown phenomena in polyethylene for point-to-plane electrode configuration has been investigated using a photo optical current measuring technique and a 760 nano-second rectangular high-voltage pulse generator. The wave forms of the prebreakdown current in polyethylene were essentially the same as those in liquid dielectrics. Discharge from positive point was more intense and faster than that from negative point in longer gap spacing. A linear relation to formative time lag and gap spacing was observed for gap length more than some critical values, which indicate a constant propagation velocity in this region. The velocities are deduced to be 1.7km/s for positive point of 50kV and 0.38km/s for negative 60kV. These values are coincident with those of liquid dielectrics. A new concept of breakdown model involving polarization effect is proposed.

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Corrosion behaviour of stainless steels in wet process phosphoric acid has been studied by immersion tests and electrochemical measurements. Effects of fluoride, chloride, sulfate and other impurities, which are usually present in the wet process phosphoric acid, have been also investigated in the present work. The increases in chromium and molybdenum contents of the stainless steel generally improved a corrosion resistance to the wet process phosphoric acid, and in particular those containing chromium above 20% and molybdenum above 2% showed the highest resistance among the stainless steels tested.
The transition from passive to active corrosion can be induced by increasing the fluoride or chloride concentration to an overcritical level, which results in a high corrosion rate.

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The volumes of polymeric gels in equilibrium with alcohol (methanol, ethanol or propanol)-water solutions were observed by using a microscope. The concentrations of alcohol inside and outside gels in equilibrium were also measured. The three kinds of gels Sumikagel S-50 (-COONa), Amberlite IR-120B (-SO₃Na) and Amberlite IRC-84 (-COONa) were used in this work.
From the experimental measurements, it was found that Sumikagel S-50 showed large volume change according to alcohol concentrations and discontinuous volume- phase transition. The alcohol concentrations inside the gel in shrinked state were much smaller than those outside the gel. No significant difference of the alcohol concentration was observed between inside and outside the gel in swelling state. For the ion-exchange resins, these phenomena were not found. The behavior mentioned above seems to be due to the structures of the polymeric gels and the interactions between polymer segments and alcohol molecules.

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In order to be applied to the cathode material in the lithium secondary battery, the characteristics of titanium disulfide TiS₂ formed by the reaction of titanium with sulfur vapour has been studied.
The SEM observation showed that the TiS₂ crystal formed under a special sulfurization condition had a preferred orientation where a-axis of TiS₂ was vertical to titanium substrate. At the X-ray diffraction pattern on its surface the peak of TiS₂ (110) was only emphasized.
It was found that the cathode of oriented TiS₂ crystal was superior in average potential and stability for charge-discharge cycles compared with the conventional cathode of TiS₂ powder, although the discharge capacity was small.

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Thermally stable multilayer films of polyimide were prepared on noble metal base electrodes by using the Langmuir-Blodgett technique. Here, the monolayer thickness of the multilayer polyimide Langmuir-Blodgett films was about 0.4 nm. We have examined the electrical properties of Au/PI/Au and Au/PI/Pb-Bi tunnel junctions.
For Au/PI/Au junctions, it was found that we could get ultrathin polyimide Langmuir-Blodgett films having a good electrical insulating property when the number of deposited polyimide layers is greater than about 30. The electrical conduction mechanism through polyimide Langmuir-Blodgett films was concluded to be ruled by the well-known tunneling theory.
For Au/PI/Pb-Bi junctions, typical I-V characteristics of tunnel junctions were obtained at a temperature below the critical temperature of a superconductitg Pb- Bi alloy, when the number of deposited polyimide Langmuir-Blodgett films was 27. It was also concluded that the electrical conduction mechanism through Polyimide Langmuir Blodgett films was ruled by the B. C. S. theory.
From thses experimental results descrided above, we found that polyimide Langmuir-Blodgett films were very useful electrical insulating materials, having a thickness of less than several tens of nm.

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The electron beam charging is the most suitable technique to inject the charge deeply into the dielectric material, such as polymers of high resistivity where the mean depth of the charge is easily estimated from the energy of the beam. The authors attempted to realize this electron beam injection by using the mini-scanning microscope (Akashi: Mini-SEM type S4). The beam energy values are 15, 25 and 35 ke V with beam current of a few na and the injection area is only about 1 cm². Very low surface potential of-9KV was observed in the vacuum although the average potential profile measured in the air was only less than-KV and so on. FEP teflon sheets with thickness of 100μm and polypropylene sheets with thickness of 60μm were charged by that method and their charging characteristics were examined by the Thermally Stimulated Discharge Currents (TSDC). A homo-current peak is observed at low temperature (40-80°C) and a hetero-current peak is also recognized in most samples (teflon and polypropylene). Some new results for the polypropylene sheet were obtained that the annealed sample shows hetero-current at a little bit above 75°C where the nonannealed sample does homo-current peak at 95°C. Typical charging time was 10 minutes which was in good agreement of the estimation from the saturation of surface potential and its charging current, but longer charging caused the new hetero-current peak at less than 70°C. Metalization of one or two side of the sheet is found to be also effective to the TSDC characteristics.

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Since a drill must have enough power to crush various rocks, it is necessary for analysis of the dynamic characteristics of a pneumatic rock-drill to consider the physical property of rock under drilling. Thus, the effect of the property of rock the dynamic charactristics of the drill was examined experimentally by using four kinds of rocks. The following results were obtained.
(1) Although the blow velocity and the air consumption are not affected by the property of rock, the number of blow is greatly affected and increased with increasing Shore-hardness of rock. This fact indicated that Shore-hardness of rock must considered as a factor affecting the dynamic characteristics of the drill.
(2) Considering the fact that the net thermal efficiency increases with increasing performance-index under drilling, it is confirmed that the previous criterion presented by one of the authors can be applied for the design of a pneumatic rock-drill.

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InN thin films, which are less studied III-V compound semiconductors, are prepared by a rf excited reactive evaporation method on glass or semi-insulating GaAs (100) substrates. The deposition conditions of the films are discussed and structures and electrical and optical properties of them are investigated. Relatively high mobility is obtained when the substrate temperature is high and the nitrogen gas pressure is low. On the other hand, relatively low carrier density is obtained when the substrate temperature is low and the nitrogen gas pressure is high. Color of the InN thin film is dark red and its band gap energy is 1.92 eV. Crystallinity of the InN thin films are improved by using the GaAs substrates.

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The principle of corresponding states was discussed for self-diffusion coeffi cient and viscosity of simple fluids. The core-repulsion part in the intermolecular potential plays a key role in the transport properties of pure simple fluids. Corre sponding states correlation for these properties can be obtained by using the scaled density alone, except for two domains; the liquid states at high pressures and low temperature, and the dilute gas states at low temperatures. For simple molecules, one parameter of each substance needed for the correlation is related to the molecular volume and the temperature at its freezing point.

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Fine ceramics manufacturing process is constituted of several processes such as material crushing, preparing, mixing, powder compacting and sintering process. These processes have each peculiar size of basic particle which causes each material behaviors and determine the material properties. In order to elucidate these material behaviors and properties thermophysically, the thermophysical three concepts of particle system, entropy and free energy have to be defined. But before defining these three concepts, we have to know the size of basic particle of each process. Because these thermophysical three concepts can be defined only by obtaining the information of basic particle size. Up to now, the size estimation method of basic particle has not yet been developed. From this point of view, in this paper, the size estimation method of basic particle especially in powder compacting and sintering processes is noticed and discussed thermophysically. As a result of it, a new size estimation method of basic particle in each process is presented by use of the thermophysical concepts of entropy and free energy, and the method is applied to powder compacting and sintering processes by use of three ceramics powder of BaTiO₃, PZT and Mn-Ni-CuO powder. And the validity of this method is checked experimentally, obtaining interesting knowledges on the hierarchy problems of fine ceramics manufacturing process.

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Some new fluorosurfactants, containing poly (N-acylalkyleneimine) portion as a hydrophilic group, were prepared by polymerization of 2-alkyl-2-oxazoline and-2-oxazine initiated by p-toluene sulfonates having perfluoroalkyl group (A, B) (Scheme 1).
These polymers were found to have good reducing power of surface tension, e. g., γ=14.3dyn/cm for aqueous solution of MeOZO-A-5 and γ=18.4dyn/cm for ethylene glycol solution of EtOZO-A-7. The polymers showed a higher cloud point, especially MeOZO and MeOZI polymers remained clear at heating upto 100°. For fluorocarbon EF-L102 emulsion the polymers showed to have a higher stabilizing power than Pluronic F-68, but for xylene emulsion a lower one than F-68.

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