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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火力発電所から大量に排出されるEPダストの約93.5%は炭素と硫酸アンモニウムから構成されており, 残りの6.5%はバナジウム, ニッケル, マグネシウム, モリブデン, 銅, コバルト, ガリウム等の有価金属の化合物から構成されている。炭素粒子はほぼ球状で, 表面には多くの孔が認あられる。硫酸アンモニウムは燃焼ガス中に含まれるSOxガスとこれを固定化するたあに添加したアンモニア水との間の反応生成物であり, 前記未燃炭素粒子や金属化合物粒子の表面を被覆するような形で存在する。X線回折法による分析では, 硫酸アンモニウムは金属と反応し, 金属硫化物やアンモニウム金属硫化物複合体となっている。蒸留水へのダストの溶解実験では, ニッケル化合物は約90%, 鉄化合物は75%, バナジウム化合物は約10%が抽出される。粒度毎に分級した試料に対する溶解実験では, ニッケル化合物は細粒からより溶解し, バナジウム化合物は粗粒からより溶解する。また, ボールミル粉砕したダストの溶解実験では, バナジウムの収率が粉砕時間の増大とともに増加する。

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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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簡単な熱分析試験によりNdF₃-Ca-CaCl₂-Fe混合物の構成物質の間の相互作用を調査した。また, その混合物からNd-Fe合金を製造するとき, 反応温度が760～1,070℃ の温度範囲で合金の形成速度およびNdF₃還元反応速度に与える影響を調べた。
還元反応が生じる前の710℃付近で固相のCaCl₂が相互溶解してNdイオンを含む溶融塩が形成されて, その溶融塩内のNdイオンは760℃ 以上の温度で急激に還元されていることが観察された。90%以上のNdF₃がCaCl₂に溶解後, 2分以内で急速に還元された。一方, 合金の回収率は反応構成物中の一つのCaが固相で存在するか, 液相で存在するかに依存するが, Caが固相で存在すればNd-Fe合金粉末がるつぼ底部に沈降することを妨害して合金の回収率を低下させた。このような理由で試料の温度がCaの融点以下のときは高い合金回収率は得られなかった。しかし, Caの融点以上の温度では1～5分で98%以上の合金回収率が得られた。なお, Caの融点以上で高い回収率をより早い時間内で得るためには試料の温度をできるだけ早くCaの融点以上にすることが重要である。

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NdF₃-Ca-CaCl₂-Fe反応系からNd-Fe合金を製造する場合についてCaおよびCaCl₂の添加量, 反応温, 円筒型軟剛材るつぼの内部直径 (D) 対長さ (L) の比, D/Lの変化が製造収率に与える影響を調べた。Nd-Fe合金はスラグとの密度差のため, るつぼの底部に生成されるだけではなく, 雰囲気とスラグ界面の周囲にも生成することが観察された。その理由は液相のCaへのNdの溶解度が大きいことと溶融塩内のCaはるつぼ内壁を這い上る (creep現象) ことの2つの複合効果で説明された。このような雰囲気とスラグ界面の周囲に生成する合金の合金量は試料温度とCa使用量を減少させることで減少することができて, その合金量を最小化する工程条件は次のように得られた。(1) D/L=1.0, (2) 試料温度=860℃, (3) Ca過剰量=5モル%, および (4) CaCl₂使用量対使用されたNdF₃中Nd量との重量比=1.15。このような条件で98.5%の合金がるつぼの底部で形成された。この合金はCa=0.42wt.%, 酸素=0.02wt.%, 炭素=0.048wt.%, 窒素<0.01wt.%, 塩素<0.02wt.%の不純物を含有してある。この中でCaは真空arc溶解により容易に除去することができた。

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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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