Deformation behavior of rockmass is strongly affected by the geometrical and mechanical properties of discontinuities, i. e. joint. Equivalent Volume Defect Method (EVDM) is one of useful methods to estimate the effective compliance of the material which contains distributed cracks. However, the application of EVDM is limited in the two dimensional problem.
In this paper, EVDM is extended, as it can apply to the three dimensional deformation analysis of jointed rock. Rock joints are assumed to be distributed circular disk cracks. The mechanical behavior of a circular disk crack has been theoretically analyzed. Equivalent Volume Defect (EVD) for a circular disk crack is formulated in two cases, i. e, crack is open or closed. It is shown that the expression of EVD for cracks can be simplified in the case of random distributed cracks. By comparing the results obtained by the proposed method to those by theoretical analysis, it is confirmed that the proposed method gives a good approximation of three dimensional and anisotropic elasticity of the material containing distributed cracks.

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Vacuum distillation and zone-melting method have been applied for the purification of commercial 4 nine Cadmium. Purity of the samples were analyzed by glow discharge mass spectroscopy (GDMS) and estimated by the measurement of residual resistivity ratio (RRR). Highest RRR value of 21000 was obtained at the central part of the overlap zone-melted specimen. Analytical results of the specimen by GDMS showed that total amount of detected metallic impurities was less than 0.1 mass ppm at this part. High purity cadmium could be successfully prepared by the vacuum distillation-zone melting method.

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A drying-disintegration system of fine particles by using a jet burner was developed. This system drys the flocculating material having high water content and at the same time disintegrates them in a process tank. Two kinds of jet burners, which are air-cooling type and water-cooling type, were used for the experiments. The drying-disintegration system having the former burner type showed the better thermal efficiency. The fine ferrite particles, having about 30 % water content and 0.8μ particle diameter, were processed at 300°. The water content of the products was 0.2%.
In order to obtain the fundamental thermal values, which are useful for designing the charcteristics of a process tank, the thermal efficiency and the volumetric heat transfer coefficient of the process tank, and the coefficient of heat transfer were calculated. The velocity of the particles was assumed same as that of gas stream in a process tank in these calculations.

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Characteristics of electrostatic precipitator dust (EP dust) in an oil-fired power station was investigated using chemical analysis, SEM-EDX, X-ray diffraction and fluorescence, TG-DTA and sieve analyses. About 93.5% of the dust is combustible, composed mainly of ammonium sulfate and carbon. The remaining 6.5 % is non-combustible compounds containing some valuable metals such as vanadium, nickel, magnesium, molybdenum, copper, cobalt, and gallium. The carbon particles are mostly spherical in shape and riddle with holes. Ammonium sulfate is formed after the addition of aqueous ammonia to prevent acid smut due to SOx gases and is observed to be coating the particles of uncombusted carbon and metal stuffs. Furthermore, the ammonium sulfate reacts with the metals to form metal sulfates and ammonium metal sulfate complexes. Dissolution test using distilled water, without adding any promoters, reveals that Ni 90%, Fe 75% and V 10% are extracted from the dust. Leaching of screened specimens shows that more nickel compounds dissolve from the finer grained samples while more vanadium compounds dissolve from coarser grained ones. Dry grinding of the dust using a tumbling ball mill gives us the increase in solubility of vanadium compounds in water with the progress of grinding.

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Reduction of palladium from ammoniacal aqueous solution with hydrogen in a gas bubbling batch reactor or an autoclave was investigated. Runs were carried out for a range of temperatures from 293 K to 353 K and hydrogen partial pressures from 0.25×10⁵ Pa to 10.0×10⁵ Pa.
The form of the palladium complex ion in the solution was found to be Pd (NH₃) ₄²⁺under the pH conditions from 6.2 to 10.0, resulting in its stability in the reactant solution for a wide range of pH.
Apparent reaction rates showed a Oth-order dependence on the palladium concentration for all values of temperature examined. The rate was linearly dependent on the partial pressure of hydrogen at lower pressures and was almost independent of the partial pressure of hydrogen at higher pressures. The activation energy given was approximately 41 kJ·mol^-1. Assuming that the Langmuir-Hinshelwood mechanism was applicable to the reaction in the present study, the rate determining step of the reaction was presumed to be the desorption step of NH₃ (i. e., reaction product) from the surface of the palladium produced.

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Interactions among the species in the NdF₃-Ca-CaCl₂-Fe mixture have been primarily investigated by employment of a simple thermoanalytical technique. Effects of temperature and time on the small scale preparation of Nd-Fe alloys from the mixture have been tested in a temperature range of 760-1, 070°C. It was discovered that the molten salt containing Nd ions was already established even at a low temperature as 710°C by mutual dissolution of solid NdF₃ and CaCl₂, hence the reduction was achievable fast even at below the melting point of metallic Ca. More than 90% of the NdF3 was reduced within two minutes as soon as the melting of CaCl₂ (around 760°C). The reason why were not obtainable high alloy recoveries prior to the melting of metallic Ca was that the solid Ca hindered Nd-Fe alloy granules to settle down to the alloy pool formed on the bottom of the crucible. In order to obtain the maximum recovery within short time, it is important to heat the charge mix to the melting point of Ca as rapid as possible. High alloy recoveries over 9% were achieved within five minutes after complete melting of Ca (around 850°C)

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Effects of dimension of a cylindrical crucible (D/L), temperature, excess metallic Ca and salt ratio on the preparation of Nd-Fe alloys from NdF₃-Ca-CaCl₂-Fe reaction mixtures have been investigated. The alloy was formed on the bottom of the crucible as well as along the periphery due to creeping action of excess Ca metal on the inside wall of the mild steel crucible. In order to minimize the alloy formation along the periphery and to improve the process efficiency, the following condition was found to be optimum:(1) the ratio, D/Lat 1.0, (2) at a temperature of around 860°C, (3) with 5 mole % excess Ca, and (4) salt ratio, the amount of CaCl₂per gram of the stoichiometric Nd in the NdF₃, at 1.15. Under the above condition, the Nd recovery in the alloy formed on the crucible bottom was 98.5% and composition by weight of the alloy was as follows: 17.2% Fe, 0.42% Ca, 0.02% oxygen, 0.048% C, <0.01% nitrogen and<0.02% chlorine. The small quantity of residual Ca was removed to a trace amount by vacuum arc melting.

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The present paper describes a hybrid controlling method for a mechanical manipulator which works for timbering of tunnel support. The manipulator was equipped with two CCD cameras and one force and moment sensor consisting of four elements to implement visual and tactile functions respectively. The vision systems allow the manipulator to recognize a support member placed on the floor whose image has been taken by a camera, and also to determine a destination, on which the work piece is to be hung, using the image of the other camera. The force and moment sensor complements the vision systems when the manipulator approaches to, grasps and releases the work piece, by sensing contact forces with the object or surroundings. A laboratory experiment has confirmed that the mechanical manipulator with visual and tactile functions can manipulate timbering of tunnel support reasonably.

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This study is a fundamental research for using the rhodan waste solution to remove nickel from nickel alloy scraps. The dissolution of nickel in basic ammonium thiocynate was studied, and its dissolution mechanism was discussed. The results obtained are surmmarized as follows: The dissolution of nickel can be effectively carried out by the blowing oxygen gas with the presence of Cu (II). The largest rate was obtained in the pH range of 9 to 9.5, but the favorable value of pH in the solution is 9, because, it is necessary to suppress the evaporation of NH3. Nickel is scarcely dissolved in the solution of Cu (II) ammine alone, however, the dissolution of nickel is sharply increased by adding of a small amount of SCN^-ions to the solution of Cu (II) ammine. And the dissolution rate is considerably higher than that in the solution containing ammonium alone. Nickel is chiefly dissolved as the amine complex Ni (NH₃) _n²⁺, and the CuSCN films is formed on the surface of nickel as the nickel is dissolved. However, it can be gradually dissolved with increasing NH₃and SCN^-ions, and subsequently the dissolution of nickel proceeds. The dissolution rate of nickel increases proportionally with the concentration of ammonium thiocyanate at its lower concentration. The activation energy of dissolution in this region was 68.5 kJ/mol. The rate-determining step is assumed to be the chemical reaction on an anodic site of the surface of nickel. At the higher concentration of ammonium thiocyanate, the dissolution rate of nickel is constant independently of the concentration, but it is proportional to the concentration of Cu (II). The activation energy of dissolution in this region was 16.3 kJ/mol. The rate-determining step is assumed to be the diffusion of Cu (II) on the cathodic site of nickel. The reactions are considered as follows: Ni+2SCN^-+2Cu (NH₃) ₄²⁺=Ni (NH₃) _n²⁺+2CuSCN (s) + (8-n) NH₃
CuSCN (s) +SCN-=Cu (SCN) ₂^-
Cu (SCN) ₂^-+4NH₃+H⁺+1/4O₂=Cu (NH₃) ₄²⁺+2SCN^-+1/2H₂O
CuSCN (s) +4NH₃+H⁺+1/4O2=Cu (NH₃) ₄²⁺+SCN^-+1/2H₂O

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Drilling tests for several types of rock were conducted to investigate the relationship between bit vibration and rock strength. An insert bit, a tooth bit and a PDC bit of 3-7/8 in. diameter were used for the tests. Rocks drilled are tuff, sandstone, granite and two types of andesite whose uniaxial compressive strength ranges from 16.5 to 167 MPa. The bit vibration while drilling was measured by two accelerometers for horizontal and vertical directions set in a rod above the bit. The magnitude of the bit vibration was obtained by the calculation of RMS (root mean square) value of acceleration. The bit weight, penetration rate, torque and rotary speed were also measured while drilling, in addition to the bit vibration.
From the results of tests, it became obvious that the bit vibration reflects well the change of rock strength. Moreover, the bit vibration, penetration rate and torque at the same bit weight were compared to understand the feature of the bit vibration. The comparison revealed that the change of the bit vibration and penetration rate with the change of rock strength are larger as compared to that of the torque in two types of roller cone bit. It also revealed that the increase and decrease of bit vibration for the change of rock strength are opposite to those of the penetration rate in the roller cone bits.

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To invesigate the behavior of coal seam around roadway faces, the laboratory experiments were taken effect by drilling test, hydrostatic compression test, gas permeability test, triaxial compression test with and without pore gas pressure and outburst fracture test.
Based on results of above experiments together with field test data from a large diameter operations for stress relief at Akabira Coal Mine, the following considerations are obtained;
Coal seam ahead of a roadway face can be devided into two regions. One is fractured region in the vicinity of the face where the stress is already relieved. Most of cracks in this region may be open so that the ductile fracture is dominant and the coal seam is relatively permeable to gas. Another is intact region under high stress ahead of the fractured region. Cracks in this region may be mostly closed so that the brittle fracture manner is dominant and the coal seam is relatively unpermeable. There is, therefore, a possibility that coal in the boundary region bursts out toward the roadway.

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