From experimental results on the fatigue of two rocks in the conditions of both natural and saturated water content under triaxial compression with pore pressure, the fatigue process was discussed paying attention to the permanent axial strain in the fatigue process and its relation to the differential stress-permanent axial strain curve (σ_D-ε _ap curve) determined from repeated loading-unloading test at constant axial strain rate.
As a result it was shown that the permanent axial strain at the outset of tertiary stage in the fatigue process, which is the point where permanent axial strain rate becomes minimum or locally minimum, approximately coincides with the permanent axial strain at the maximum differential stress in σ_D-ε _ap curve and that the failure points lie on the post-peak region of σD-εap curve. Thus the fatigue process proceeds in the differential stress-permanent axial strain diagram being closely related to σ_D-ε_ap curve.
A new mechanism which explains the fatigue process described above was proposed and practically verified with experimental results. The permanent axial strain represents the degree of accumulative damages in rock and the permanent axial strain rate at certain permanent strain in the fatigue process depends on the difference between the differential stress σ_D in σ_D-ε_ap curve at the permanent axial strain and the applied differential stress (σ1-σ3) f in the fatigue test, which means that the permanent axial strain rate depends on the room in load carrying ability of rock and therefore the permanent axial strain rate increases with decreasing of the difference and vice versa.

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Powered supports were analyzed to establish a new index with emphasis on evaluation of their performance. The new index was applied to compare the deformation characteristics of ten types of powered supports one another. The main results obtained from this investigation are as follows.
1. The deformation characteristics of a powered support can be indicated in terms of a (2×2) global stiffness matrix. This is a symmetrical matrix whose diagonal components represent the convergence and shear stiffnesses of powered support, whereas its off-diagnal ones are interactive stiffnesses.
2. The global stiffness matrix depends on the the height of powered support. Above all the convergence stiffness varies significantly with the mining height. The convergence stiffness is always greater than the shear one over the entire range in the capable mining height.
3. The stiffness of hydraulic legs mainly determines the convergence component of the global stiffness, whereas the stiffness of caving shield affects on its shear component.
4. The convergence performance tends to sacrifice the shear deformation one, and vice versa. 4-leg chock shield supports can compromise the shear characteristics with the convergence one better than the other types. Front and rear legs should be either stood vertically or tilted slightly forward and backward respectively.
5. The principal direction of the global stiffness matrix allows us to choose well-balanced deformation characteristics. To assure deformation performance as properly as possible, the principal axis of the global matrix should be tilted by 15 to 25 degrees of the angle from the vertical towards the canopy tip.

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In order to know flow patterns and in-situ solid concentration profiles in an opaque pipe, it is necessary to view the flow with X-ray or neutron radiography, and to process the obtained image. As the fundamental study of this purpose, the in-situ solid concentration in a transparent acrylic pipe has been estimated by processing optical video images. The result of the image processing has been compared with the actual solid concentration profile which was obtained by the rapid shut-off method. The comparison indicates that if we can estimate the amount of overlapped particles with adequate threshold values, the image processing gives accurate in-site solid concentration profiles.

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The liquid-phase reduction method for synthesis of metallic ultrafine particles is known to be advantageous to the production for bimetallic ultrafine particles.By use of this method, the following results were obtained.
(1) In aqueous media, the increase in drop-rate of a reducer solution into a metal salt solution caused the remarkable decrease in the particle size for Ni-Zn bimetallic fine particles.
(2) The strong dependency of the particle size on the synthesis temperature was found in both aqueous and nonaqueous media for Ni-Zn bimetallic fine particles
(3) By means of X-ray diffraction analysis, metallic Ni ultrafine particles produced in nonaqueous media were found amorphous.
(4) Amorphous Ni-Zn ultrafine alloy particles were easily produced with the addition of a reducer solution into a Ni-Zn bimetal salt solution. However, no formation of alloy phase was give the synthesis of o-Zn bimetallic ultrafine particles by the similar manner.

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Since metallic ultrafine particles are known to have characters different from bulk-phase, such particles are expected to be applied to various materials, in particular, catalysts. The surface reaction characteristics of metallic ultrafine particles produced by the liquid-phase reduction method were investigated. The possibility of such particles as a catalyst for benzene hydrogenation which was sensitive to the surface character, was also studied, giving the following results.
(1) Metallic Ni ultrafine particles synthesized by the liquid-phase reduction method were found more active for benzene hydrogenation to cyclohexane than the conventional Ni catalyst. The catalytic activity reached a maximum at a quantity of reducer, LiAlH₄, enough for the reduction of Ni cation into metal.
(2) The addition of Zn to Ni ultrafine particles resulted in the great enhancement of catalytic activity. This Zn effect could be accounted not only by the change in a surface area, but also by the ensemble and ligand effect.
(3) Metallic Co ultrafine particles were found to have high catalytic activity which was much higher than on Ni particles.
(4) The promotional effect of the addition of Zn to Co ultrafine particles were found negligible. Since no Co-Zn alloy phase in the X-ray diffraction analysis was obaerved for Co-Zn bimetallic ultrafine particles, the ensemble effect and/or the ligand effect of Zn to Co could not be induced.

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The anodic behavior of Pb-Ag-Ti tertiary alloys has been investigated in sulfuric acid solution (150g H₂SO₄/l) at a current density of 50 mA/cm²at 40°C. The contents of silver and thallium in the alloys tested were up to 0.8 wt% and 1.4 wt%, respectively.
The electrode potential, the rate of formation of the anodic oxide layer and the amount of anode slime were determined for both the rapidly solidified samples and the slowly solidified ones. X-ray diffraction analysis and the SEM observation were performed to characterize the anodic oxide layers.
1) The electrode potential was observed to be significantly lowered by an increase in the silver content in the alloy and to increase only marginally with an increase in the thallium content.
2) At each silver content, the rate of growth of the anodic PbO₂layer was found to be affected only slightly by the alloying of thallium.
3) The alloying of thallium favoured growth of β-PbO₂crystal at a lower content of silver in comparison with that of the Pb-Ag binary alloys and yielded a smooth anodic oxide layer of a denser structure.
4) The thallium-alloying noticeably reduced the amount of the anode slime over the duration of the polarization performed in this work (up to 32 days), though affecting only slightly the electrochemical behavior of the alloys.

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The rate of sulfur absorption into molten slags from CO-CO₂-S0₂ gas mixture was measured under agitation speed of 800 rpm in a molten slag and 1, 000cc/min of gas flow rate. A reaction mechanism of sulfur absorption could be treated as an electrochemical reaction. The effects of P_O2, P_S2 and the composition of slag on sulfur absorption were investigated. The rate of sulfur absorption was propotional to p_O2^-1/2 and P_S2^1/2 in the atomosphere. And also, it was found that the rate increased with increasing the slag bascity and increasing FeO in the slag. Furthermore, the effect of slag composition on the efficiency of sulfur absorption into slag under the reducing atmosphere was better than the oxidizing one.
A reclamation of slag as absorbent of sulfur was estimated.

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The miscibility gap between speiss and metallic lead as well as silver and gold distribution were determined at 1200°C in the Pb-Fe-Sb and Pb-Cu-Sb ternary systems.
Phase separation between speiss and metallic lead occurs in the 37-53 mass% antimony range in speiss of the Pb-Fe-Sb system. Below this composition, solid iron precipitates to form a three phase equilibrium region. Mutual solubility between the speiss and the lead phases is relatively small and minimum lead solubility in speiss is about 5 mass%. However, antimony is not entirely concentrated in speiss since antimony content in metallic lead is one-half the content in speiss. The miscibility gap in the Pb-Fe-Sb system is narrower than in the Pb-Fe-As system, while the two phase region in the Pb-Cu-Sb system plotted in atomic percent depicts a nearly identical miscibility gap as in the Pb-Cu-As system at 1200°C.
In the Pb-Fe-Sb system, a decrease in the iron distribution coefficient between speiss and metallic lead, defined as L_FesP/Pb (mass% Fe in speiss)/(mass% Fe in lead), results in an increase in the silver distribution coefficient from 0.1 to 0.8, suggesting an intimate relationship between silver distribution and iron activity. The distribution coefficient of silver in the Pb-Cu-Sb system is about unity.
The distribution coefficient of gold in the Pb-Fe-Sb system is approximately 0.8, whereas in the Pb-Cu-Sb system it is about 5, demonstrating a capacity for speiss to absorb an appreciable amount of gold. Therefore, a potential exists for utilizing speiss as an extractive medium to collect, for example, copper and precious metals dissolved in slag.

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