In-situ measurements of the permeability in such soft rock ground as an uranium ore vein of soft congromerate and its footwall of weathering granite at the Ningyo-toge Uranium Mine were carried out.
The permeability coefficient of the weathering granite ground was determined by an in-situ pumping test and the obtained value was 4×10^-4-5×10^-6cm/sec, and it is in satisfactory agreement with the laboratory test results reported previously.
The in-place leaching tests to withdraw the pregnant solution by the suction pump were performed under some several conditions in a zone (8m×15m×3.5m) of the ore vein.
The results show that the withdrawing rate of pregnant solution is closely related to the viscocity of the solution, the suction pressure and the distribution of suction holes, and that most of the correlations among them can be explained by the concept of the effective withdrawal radius deduced by the laboratory tests.

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Uni-axial, bi-axial and confined compression tests were performed on Akiyoshi Marble. Specimens were unloaded on several stages of these experiments, and optical micro-scopic observations were performed about thin sections made from these specimens. On the other hand, uni-axial compressive test was also performed on calcite specimens.
Based on these experimental results, some considerations about strength failure of these materials were discussed and following conclusions were obtained.
1) The fracture behavior of calcite was anisotropic. In c-axis direction it behaved as brittle, on the other hand in a-axis direction it behaved as elasto-plastic. And, the strength failure and yielding point was about 1500 and 40kg/cm² respectively.
2) The linearity at low stress level and non-linearity at high stress level of the stress-strain relation of marble could be explained by the mobilization of the hindered cleavage sliding of calcite grain due to micro-crackings surrounding the grain.
3) The extended Von Mises fracture criterion well explained experimental results qualitatively, but quantitatively insufficient.
4) The anisotropy of lateral strain under bi-axial compression could be explained by the directional development of cracking from pre-existent cracks.
5) The formation of ultimate failure plane did not correspond to the point of strength failure, but rather corresponded to the rapid stress drop after the strength failure.

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In order to predict the relation between friction factor and Reynolds number forBinghain plastic fluid flow in circular smooth pipes, an improved mixing-length distribution is proposed in this paper. The distribution (i.e. Eq.(18)) is a modification of Van Driest's model for Newtonian fluid flow that is obtained through the results of the other researchers' studies about Newtonian and Bingham plastic fluid flow and the authors' mixing-length distribution for pseudo-plastic fluid flow in circular smooth pipes.
The proposed mixing-length distribution makes it possible to predict the pressure loss of Bingham plastic fluid flow in circular smooth pipes since 163 out of 194 experimental data shown in Fig. 8 are within ±7% of the theoretical values. A set of theoretical design curves of friction factor versus Reynolds number is calculated and shown in Fig. 9.

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As we previously stated in the 1st report (1957) and the 2nd report (1959), thewriters carried out a research on the water reservoir of the cretaceous formationunderlying the Harutori coal bearing formation.
With newly obtained data for 20 years, it is our intention to describe herewith conditions of the water reservoir and filling lnflammblae gas, which can be summarised as follows:
1. The distribution of the chlorine content in the water reservoir has the same pattern with the general trend of the geological structure, the content increasing as the reservoir becomes deeper: contour intervals of the Cl content correlate with the depth of the reservoir, fine nearer the surface and coarse at deeper levels, and fixed at about13, 000mg/L. The area of Minami-Masuura, however, has peculiar features.
2. The thickness of the water reservoir is 40m-50m, the voids ratio at the Harutori area is about 6%, and the fissures of the reservoir are almost horizontal and cross with angles of 70°-80°.
3. By boring and drainage wells, each water level of the reservoir has been proved different by one block of geological structure as shown in Fig. 1.
4. The cavity occurred due to lowering of the water level of the reservoir is filled with inflammable gas separated from the connate water.
5. The initial pressure of the gas filling in the cavity is 0.5kg/cm², and the gas water ratio of the connate water is calculated pretty higher than the theoretical value.
6. The Fig. 4 shows the gas productivity index of the reservoir as a regional feature indicating quantity of the waterspout and the production rate of the gas.
7. The Table 5 indicates free gas resources of the water reservoir by one block of the geological structure. We estimated the annual production with the present reserve as 5, 000, 000 cm³, and taking account of the increase by pondering connate water, the possibility can be higher.

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To investigate the possibility of effective disintegration of weathered granite in dry system, the continuous disintegration tester was newly designed. The tumbler tester was also used as disintegrator for comparison to the result from the disintegration tester. The results obtained are as follows:
1) From the results of particle size distribution of treated samples and mineral composition of the product under 74μm, the following optimum disintegration conditions for both testers were determined.
The designed tester: Feed rate=5.7kg/min. Height of outlet=80cm. Impeller speed=100 rpm.
Tumbler tester: Amount of feed=10kg/batch. Total number of revolution=400 (16.7 minutes).
2) The designed tester can disintegrate the sample continuously. In spite of increasing the weight ratio of the product under 74μm in treated sample, the mineral composition of the product in the treated sample is almost same as that in the untreated sample.
3) In the present experiment, seven samples were examined. Especially, highly weathered sample from Iizuka-shi, Fukuoka-ken gave the silica sand with rather high quality in coaser part and the clay with almost same quality as the decanted one in finer part (-37μm)

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The authors, in 1975, developed the chain system sedimentation balance for the analysis of particle size distribution of powder. The present paper discusses the accuracy of measurement by this apparatus.
(1) The influence of room temparature variation appeared as a variation of the weight. It was revealed that this phenomenon is caused by air convection around the hanging wire of the weighing pan in the balance box. In order to prevent this effect, heat transfer from the room to balance box was cut off by covering the apparatus with a styrene resin plate containing air bubbles. The zero point of the balance is maintained constant for a long period of measurement.
(2) By using heavy and light types of the weighing pan, particle size distribution analysis of quartz powder was repeated 10 times for each type under the same conditions. The particle size distribution curves obtained by the two type pans agreed with each other very well. For better agreement of the results, it is better to reduce the discrepancy between the distribution curves in the large particle size region.
(3) The ratio of the weight of the suspended particles which will actually settle on the weighing pan to that of the ideal weight was calculated. This ratio (n%) represents the index of accuracy of the measurement. In this experiment, n% was obtained as 79.6±1.9 and 76.7±3.3% for the Heavy type and Light type weighing pans respectively.

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It has been considered desirable to develop effective techniques for utilizationof waste solids. The main waste solid is urban waste which includes garbage, paper, plastic, and others. Larger waste solids are scraps of home electric machineries, automobiles, etc. Except for iron, other metals are hardly recovered at this stage. Various researches continue in order to provide satisfactory systems for separation of different metals from each other. They are magnetic separation, sink-float separation using heavy dense medium suspension and sink-float separation using magnetic fluids. In particular, a sink-float separation using magneticfluids can be used to separate many kinds of nonmagnetic metals whose specific gravities are different. Electric magnets and kerosene based magnetic fluid were used at first with this system. However, the present composition of waste solids, it is inferior to the smelting method. Therefore, we used water based magneticfluid in view of its greater regenerative qualities. Also, we used ferrite permanent magnets with yoke because the cost price is lower.
This report concerns the separation of Al from mixture of Al and other, heavier nonmagnetic materials. Al-Zn, Al-Cu mixture (about 6 to 30mm), whose weight percent of Al is 50, havebeen separated almost perfectly within about 2 t/hr. It was found to be more difficult to separate a mixture that includes a greater amount of Al, however, nearperfect separation of Al-Zn mixture (about 6mm) whose weight percent of Al is 90has been obtained within about 1.2t/hr.

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Authors reported the results about the leaching of Ni from garnierite ore by using HNO₃ solution as the leaching medium previously. In this report, at first, the experimental data of the leaching of Ni from garnierite ore by using H2 SO4 solution as the leaching medium were statistically researched. Next, the experimental data of this time, and the data of the previously reported, were arranged to the orthogonal array, and a series of experiment of using H₂SO₄ solution and HNO₃ solution as leaching medium were performed.
The effects on the extraction of Ni, Fe, MgO from the ore by the difference between H₂SO₄ solution and HNO3 solution as the leaching medium were statistically treated and compared.
The results of these comparison showed that the former heighten the extractions of Ni, Fe, MgO from the ore than the later. When the process decreasing the extractions of Fe, MgO from the ore is developed, to use H2 SO4 solution as the leaching medium may be profitable to the industrial process, because of the lower price of H₂SO₄ than HNO₃.

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Recently, the roast-reaction in lead sulfide has been expected to come to the fore in relation to the days of high grade lead concentrates and energy conservation. In addition, the roast-reaction is noteworthy in the following thermochemical splitting of hydrogen sulfide:
2Pb(1)+2H₂S=2PbS+2H₂
PbS+2SO₂=PbSO₄+2S°
PbS+PbSO₄=2Pb+2SO₂
2H₂S=2H₂+2S°
Experiments were carried out by using mixtures of galena powder and reagent grade PbSO₄ over the temperature range 650 to 750°C in a stream of inert gas. The progress of the reaction was followed with continuous analysis of evolved SO₂. The reaction products were analyzed by X-ray diffraction.
From the results obtained in this study, it can be concluded that:
1) It has been demonstrated that gaseous PbS was thought to take an important part in the Pb formation.
2) PbSO₄ is rapidly converted into PbO·PbSO₄ in the presence of gaseous PbS.
3) This basic sulfate moves from 2PbO·PbSO₄ to 4PbO·PbSO₄.
4) Over the lower temperature range, 4PbO·PbSO₄ is easy to produce metallic lead by the reaction with gaseous PbS.
5) Increasing temperature tends to promote the formation of metallic lead from 2PbO·PbSO₄.
These conclusions could be supported thermodynamically by log Pso₂-logPpbs (g) equilibriudiagram.

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