The permeability tests, using a transient pulse method, were carried on KIMACHI sandstone under various confining and pore pressures.
From the experimental data, it is recognized that permeability is underestimated when it is assumed that there is no storage in the rock specimen. Also, permeability increases as the pressure difference between both end pore pressure of the rock specimen increase.
Under constant pore pressure, permeability decreases gradually as confining pressure becomes higher. But, it is found that permeability is remarkably affected by pore pressure rather than by confining pressure.
Under constant confining pressure, permeability decreases as differential stress increses. With further increase in differential stress, permeability increases.

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Buffers with various shapes and aspect-ratios, attached axially to a vertical spring, were vibrated longitudinally in still water by a vibrator which excited the top of the spring with a sinusoidal displacement. Then, the drag and added mass coefficients were analysed by introducing the experimentally obtained values of buffer's amplitude and frequency in resonance as well as the amplitude of the forcing displacement to the solution of a springmass-damper system.
The results obtained are as follows:
(1) There is a good correlation between the drag and added mass coefficients of buffers vibrating longitudinally in water and the number of Keulegan-Carpenter, Kc. However, there is no clear correlation between those coefficients and Reynolds number.
(2) The drag coefficients decrease exponentially as Kc increases. Then, the drag coefficients approach the constant values when Kc exceeds some values. These constant values are about 1.0 for a cylindrical buffer, about 0.35 for a cylindro-semispherical one and about 0.3 for a cylindro-conical one. Furthermore, these values are independent of aspect ratios.
(3) There is a linear relationship between the added mass coefficient and Kc. In case of a cylindrical buffer, the coefficient increases as Kc increases and the rate of increase is greater in smaller aspect-ratio. In cases of cylindro-semispherical and cylindro-conical buffers, however, the coefficients decrease as Kc increases and the rates of decrease are greater in larger aspect-ratio.
(4) The absolute values of those added mass coefficients are compared with each other in case that Kc is equal to 10. These values pertaining to the aspect-ratio of 1 are about 1.1 for a cylindrical buffer, about 0.3 for a cylindro-semispherical one and about 0.25 for a cylindro-conical one. On the other hand, the values pertaining to the aspect-ratio of 3 are about 0.2 for all buffers.

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Phase relations of iron-zinc-oxygen system at 1100K have been determined by the X-ray microanalysis and X-ray diffraction studies of the quenched samples. Also the partial oxygen pressure have been measured by the e.m.f. method using the zirconium oxide solid electrolytes. The activities of Fe and Zn in the alloys as well as the activities of FeO and ZnO in the oxides were obtained by applying the Gibbs-Duhem relation to the alloy and oxide phases. The results are summarized as follows:(1) Phase relations of Fe-Zn-ZnO-FeO system at 1100K were composed of two-phase fields (Fe+FeOs.s., Fes.s.+ZnOs.s. Zn (1)+ZnO) and three-phase fields (Fe+ZnOs.s.+FeOs.s., Fes.s.+Zn (1)+ZnO). The mutual solubilities between FeO and ZnO were determined.(2) Activities in Fe-Zn alloys at 1100K showed considerable positive deviations from Raoult's law except the activity of zinc at Zn-rich region which exhibited a negative deviation.(3) Both the activities of FeO and ZnO in solid FeO-ZnO system at 1100K showed considerable positive deviations from Raoult's law except the activity of zinc oxide at ZnO-rich side which exhibited no deviation from Raoult's law in the range up to the solid solubility limit. The activity coefficients at infinite dilution, γ⁰FeO andγ⁰ZnO, at at 1100K were estimated at 4.4 and 6.6, respectively.

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For urgent demands of rare metals, new processes which enable the production of advanced materials with high added value from cheap raw materials, are waiting to be studied.
In this study, formation of ultrafine Nb₂O₅ powder (UFP Nb₂O₅) from ferroniobium via alkoxides was investigated.
The problems concerned and corresponding results obtained were as follows: 1) NbCl₅containing FeCl₃was produced by direct chlorination of ferroniobium powder. 2) Nb (OB_uⁿ) ₅and Nb (OP_rⁱ) ₅were synthesized and purified from NbCl₅-FeCl₃mixture by ammonia method. 3) Primary separation via chloride and following purification via Nb (OB_uⁿ) ₅, decrease iron content under 10 ppm and industrially available process was proposed. 4) Purification process via Nb (OP_rⁱ) ₅ was found effective for tantalum removal. 5) Monodispersed UFP Nb₂O₅ with average particle size of 0.2μm was obtained by hydrolysis of Nb (OBun) 5. 6) Some characterizations of UFP Nb₂O₅, such as, crystal structure, thermal stability were conducted and PZC obtained from electrophoretic measurement was 3.3.

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Solvent extraction of indium (III) and gallium (III) from nitric acid or aqueous mixture of nitric acid and sodium nitrate solution was investigated using four kinds of acidic extractants, i. e. di (2-ethylhexyl) phosphoric acid (D2EHPA), 2 ethylhexyl 2-ethylhexylphosphonic acid (EHEHPA), di (2, 4, 4'-trimethylpentyl) phosphinic acid (DTMPPA) and 2 bromododecanoic acid (2-BDA), and using toluene as a diluent to identify the extracted species and to evaluate their extraction equilibrium constants. Indium (III) was extracted as the monomeric complex of the type, InR₃.3HR, with all extractants. On the other hand, gallium (III) was extracted as the monomeric complex of the type, GaR₃, with D2EHPA and EHEHPA while as the complex of the type, GaR₃, with DTMPPA and 2-BDA.
For both metals, the extraction equilibrium constant increases in the sequence, 2-BDA<DTMPPA<EHEHPA <D2EHPA, which is in accordance with the sequence of acidity of these extractants. The equilibrium constants of indium (III) are greater than those of gallium (III) with all extractants and their ratio increases also in the same sequence as mentioned earlier; the ratio with D2EHPA is above as great as 10₅.

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