The microgeometry or texture of a porous medium determines the physical properties, e.g., the transport and acoustical properties of sedimentary rock. In order to better understand the relation between microgeometry and permeability, samples of two sandstones (Shirahama and Kimachi) were submitted to hydrostatic pressure cycles while pore pressure was kept constant.
For loading, the permeability decreased obviously at the low pressure level, and decreased slightly when the pressure increasing. For unloading, the permeability was little altered by the pressure change, contrary to the loading condition. Cycling the hydrostatic pressure caused nonrecoverable changes (hysteresis) in permeability, volumetric strain and velocity (P-wave and S-wave).
A series of blue dye expoxy-impregnated thin sections of the two sandstones was prepared from the stressed and unstressed samples. Using an image analyzer the porosity of Shirahama sandstone decreased from 6.54% to 4.86% after stressed to 49 MPa. Closure of pores caused the hysteresis in permeability, volumetric strain and velocity of Shirahama sandstone. Instead of pore closure, compaction of clastic caused the large hysteresis in volumetric strain of Kimachi sandstone. It is clear that these characteristics of the permeability have a close relation with the microgeometry.

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Lime has been often used as a precipitant for phosphorus removal from wastewaters. But the calcium phosphate precipitates formed have unfavorable settling characteristics. The effect of the addition of various mineral powders has been investigated in order to improve settling characteristics of the precipitates and enhance phosphorus removal.
The highest phosphate removal was obtained by adding dolomite. The addition of dolomite improved the settling characteristics of the calcium phosphate precipitates, perhaps due to its' attachment to dolomite powder. As a result, the pH range where high removal of phosphorus was obtained became wider and the settling time decreased. Although it is desirable to stir a solution containing dolomite and Ca²⁺ ions for at least 1 hour in order to crystallize calcium phosphate precipitates and cause its' attachment to dolomite powder, high removal of phosphorus could be obtained in the wide pH range even by shorter stirring time, if settling time was somewhat prolonged.

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For the design of a tunnel, the effect of pore water flow should be taken into account to predict rock deformation accurately since deformability as well as strength of the saturated rock are affected by pore pressure.
In this paper, a technique of numerical analysis on coupling problem of rock deformation and pore water flow is discussed from this point of view.Basic equations governing the mechanical interaction between rock and pore water are obtained, based on the Biot's model with additional assumptions. A numerical technique to solve these equations approximately under the arbitrary initial and boundary conditions is also proposed. To examine the validity of the basic equations and the proposed solution technique, numerical results for one-dimensional consolidation problem are compared with the analytical solution. The excavation of a circuler tunnel is also simulated in order to discuss the interaction of rock and pore water.
Conclusions are summarized as follows:
(1) Numerical technique employed to solve the equations provides the results with adequate accuracy.
(2) The intensity of interaction between rock and pore water depends on the difference of bulk modulus measured under drained and undrained conditions.
(3) When a tunnel is excavated rapidly, pore pressure can exceed the minimum compressive stress near the tunnel wall. This means that rock failure should be taken into consideration for more practical analysis.

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Physicochemical properties, such as molar volume, surface tension, viscosity and electrical conductivity of alkali halide melts are discussed on the viewpoint of the interaction between the cation and the anion. As the alkali halide melt coheres with long range coulombic force and the physicochemical properties should depend on the radii of the cation and the anion, the systematic study was made on the properties as the functions of the ionic radii. Thermodynamic properties measured almost change according to the order of ionic radius, for example, surface energy increases with decreasing the cationic or anionic radius except lithium halides. It is considered that the phenomena indicate that the cohesive force based on coulombic energy decreases because the short range ionic interaction appears i.e. lithium and sodium ion polarize the anions. In contrast with the thermodynamic properties, transport properties measured do not necessarily show the systematic change with the cationic or anionic radius. It is considered that the transport properties depend on many factors, and the short range interaction plays more important role for transport properties than for the thermodynamic properties.

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Lately, it is becoming clear that plasma nitriding method has several differencial features comparing with ion nitriding. In this study, plasma nitriding of pure iron and SUS304 steel was carried out using r.f. nitrogen glow discharge. There were significant differences between pure iron and SUS304 steel in properties and growth mechanism of the nitrided layer with the temperature increase. In the plasma nitriding of pure iron, the nitriding rate was much higher than that in the ion nitriding processes for pure iron reported so far. The nitriding rate of SUS304 steel decreased rapidly as the nitriding time proceeded.
The nitriding of pure iron and SUS304 steel using N₂-H₂ gas in r.f. plasma was impossible owing to the effect that activated hydrogen checked the growth of the nitrided layer.

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Activity of lithium in molten Al-Li alloy up to 3.3at%Li has been measured in the temperature range between 950K and 1, 100K. Method used is based on measuring the EMF of Li ILiCl IA1-Li cell in which all the materials are liquid states. Al-Li alloy is made by addition of lithium electrolytically into molten aluminum and Li electrode is prepared by the deposition of lithium also electrolytically on the tungsten wire. Potensials of the electrodes are measured against Ag/AgCl electrode which is in mullite tube and shows very stable potential. EMF of the cell is determined as the difference between the potentials of Al-Li and Li electrodes measured vs. Ag/AgCl electrode. As all the sequence of procedures, preparing electrodes and measuring electrode potentials, are performed in molten LiCl, the electrodes are not affected by the atmosphere and are kept clean. Therefore, highly reliable and precise measurements have been carried out.
Activity coefficients of Li in the alloy are 0.21 and 0.28 at 973K and 1, 073K, respectively if Henry' law is assumed in the composition range measured. However, the activity coefficient slightly depends on the composition. Then thermodynamic quantities, partial molar enthalpy, partial molar entropy and excess partial molar entropy have been determined by using the results obtained, and the activity coefficient has been determined as a function of composition and temperature.

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Chemical vapor deposition of VB₂ on mild steel substrate was carried out with the hydrogen reduction of VOCl₃-BCl₃ mixture at the temperature range of 1, 073 to 1, 223K, [VOCl₃/(VOCl₃+BCl₃)] gas molar ratio region of 0.23 to 0.61, and reduction time of 1.8ks.
Thin films of 50μm consisting of pure VB₂ phase have been synthesized on the conditions of substrate temperature 1, 173K, and the gas ratio above 0.40. Smooth surface film of VB₂ having micro-vickers hardness of about Hmv 2, 800 have been prepared at gas ratio above 0.5.

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Interfacial tensions between water and some organic solvents were measured by the pendant drop method. Interfacial properties obtained in the present study were in agreement with the previous data. Effect of additions of some extractants on the interfacial tensions in the systems were also investigated. An ability of lowering the interfacial tensions between water and some organic solvents became strong in the order of D2EHPA, MIBK and TBP.
Emulsion formation and phase separation behaviors in the systems were directly observed and recorded by a video camera. Minimum stirring powers to form an emulsion in the present study systems were found to be related with the interfacial tensions as shown in following equation (1).
L=10 (γ-85.8/24.7)...(1)
L: minimum stirring power to obtain emulsion state
γ: interfacial tensibn in water-organic solvent system On the other hand, phase separation behaviors were not simple. Disappearance times of the emulsions after stopping the stir were independent on the interfacial tensions in a water-benzene system. Two different linear relationships between the disappearance time and the interfacial tension were obtained in a water-kerosene and a water-hexane system, respectively.

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Disproportionation reaction (2Cu⁺ Cu⁰+ Cu²⁺) of acidic cuprous sulfate solution was studied to obtain fine copper powder suitable for conductive paste.In order to obtain 1mu;m-class copper powder, 1e of the cuprous solution, equilibrated with metallic copper at 220°C was injected into a large stainless reservoir containing 452 of acidic cupric sulfate solution, followed by slow cooling to room temperature.
Mean particle diameter and shape of the powder obtained could be controlled by changing the amount and temperature of cupric sulfate solution in the reservoir. Mean particle diameter of powders could be controlled from 0.7μm to 10μm with narrow size distribution. The fine copper powders thus obtained had flat crystal surface planes and had an excellent oxidation resistance.

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