A brief historical review is described of the university-industry research cooperation, which has been conducted by both the MMIJ (the Mining and Materials Processing Institute of Japan) and the 69th committee of the JSPS (the Japan Society for the Promotion of Science), in the field of non-ferrous metallurgy in Japan. The author divided the latter half of this century into five periods which are the recovery since the war period (1945∼65), the highly developed period (∼75), the technology rearmament period (∼85), the exotic materials period (∼95), and the global environment period (95∼). Modern technology of non-ferrous extractive metallurgy with automation, energy saving, pollution control, functional materials production and so on, originated in the third period just after the oil-shock, where the university-industry research cooperation activities played an essential role. In appreciation of the contributions to which, the author was awarded the 73rd Watanabe prize. For the future development of materials processing technology, the author is proposing a new concept of "metal laundering".

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IBUKI Limestone Quarry started operation from 1952. In order to obtain limestone ore resources, the exploitation plot plan for the upper lever was first considered in early 1970's. This area is adjacent to the natural park and natural monument area where high mountain plants are growing in groups. Prior to making the plot plan, the exploitation concept was discussed with experts and local communities and determined with regard to the natural environment. According to this concept, the excavating system including restoration on the planting and transporting system of limestone ore were developed. In order to verify restoration by planting and also to confirm the coexistence with mining work, the planting work had been performed since 1971 at the already excavated area below 1,000 meter level. On the other hand, the facilities for ore transportation were installed underground so that it cannot affect the existing landscape. Although rock had enough strength, strength of rock mass was not high due to considerable cracks observed. When the vertical ore shaft was constructed in the cracked rock, the diameter of the shaft was designed as a small scale and the walls were reinforced with concrete and steel ringing. To avoid choking in the shaft, the rock size supplied to the shaft is made under 300 mm using a mobile crushing plant. The operations in the upper limestone quarry was started in 1978, then the restoration planting at the upper limestone quarry was started in 1979. At the beginning of operation, there are many unexpected troubles in operations. This paper describes a design of exploitation which agreed with the concept, countermeasure for the troubles in operations, additional construction work to improve the environment against dust emission and the restored results in the excavated area.

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From a view of energy security, the development of domestic energy is very important in Japan. We have the low production rate and import most of the energy from the foreign countries. And from the view of the natural environment protection, the geothermal energy is effective to lower discharges of the carbon dioxide and so on than the other energy resources. In December, 1998, we had the COP 3 in Kyoto city, many developed countries decided the numeral goals about the amount of discharge gases(6 gases including carbon dioxide) to the year of 2008 ∼ 2012. At present, the development of geothermal energy becomes very important as well as the development of solar energy, wind energy and wave energy in Japan. In this paper, I will introduce the history and the problems about the development of geothermal energy and the processes of electric power generation by the geothermal steam from the deep parts of underground, and explain expectations about the future of the development of geothermal energy for a reference.

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For the attainment of a type of steady state, where no flow of matter exists in a single phase fluid system, a new criterion is presented. Gradients of temperature and composition may exist in the system, but the pressure and the enthalpy per unit volume must be uiform throughout the system. It is shown that the criterion reduces to a simple expression in terms of activity, and a new method of activity measurement is proposed. Effects of chemical reactions on the criterion and the way of avoiding the effects by selecting appropriate components are also discussed.

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Three-dimensional in-situ stresses in a hard limestone lying about 700 m below the surface were estimated by five core-based methods (ASR, DSCA, PSHA, DRA and AE method) and a stress relief method (Conical-ended borehole method ; CEBM). The confidence intervals of the results by CEBM were estimated, and then, the results by the core-based methods were compared to those by the CEBM to examine the reliability of the core-based methods for this particular rock. The ASR method was difficult to estimate reliable in-situ stresses in this hard limestone whose Young's modulus ranged from 40 GPa to 80 GPa. A more accurate measuring system was required to apply ASR method to such a hard rock. The DSCA (OC), the PSHA and the DRA (Δεmax )(ε) method estimated the in-situ stresses relatively consistent with those by the CEBM. The agreement of the results by both the conventional DRA and the AE method with those by the CEBM was poor for the rock.

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A powder mixture of calcium oxide (CaO) and silica-gel (amorphous SiO2) was subjected to grinding under dry atmospheric condition using a planetary ball mill to investigate its effect on synthesis of para-wollastonite (CaO·SiO2) powder by heating. The grinding of the mixture changes a crystalline structure of CaO into amorphous one within 5 hours. Accordingly, the mixture ground for 5 hours aggregates with homogeneous chemical composition, leading to the formation of a precursor of para-wollastonite by heating at 923 K. Para-wollastonite can be synthesized by heating the mixture ground for 2 hours at 1,273 K for 2 hours, while heating at around 1,400 K for about one week is necessary to synthesize it from the original mixture.

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From the view point of separation of metal and slag, reduction ratio, and impurity content of neodymium, the optimum reduction conditions are 1,740 K and 0.9 ks for reduction with 1.2 times calcium in excess of stoichiometry.

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An experimental study was carried out on the characterization of Ca in rare earth (R) alloy powders produced by the reduction-diffusion (R-D) method using metallic Ca as reductant. SmCo5, Sm2Fe17, Nd15Fe77B8, NdFe1.7Co0.3, Tb7Gd13Fe80 and MMNi4.2Co0.2Mn0.3Al0.3 (MM：mischmetal) alloy powders were prepared by the R-D method. The Ca content of the alloy powders by chemical analysis was from 0.03 wt. % to 0.45 wt. %. A SEM observation and an EPMA analysis of cross section of the alloy powders revealed that Ca was solute atom in several intermetallic compounds. The Ca content of intermetallic compounds increased as the rare earth content of intermetallic compounds increased. The Ca content of the alloy powders by chemical analysis and the sum of the Ca content of the intermetallic compounds by EPMA analysis were in agreement.

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An aqueous H3RhCl6 solution was treated by N2H4 reduction for the purpose of producing fine Rh powder. The reaction behaviors were investigated at temperatures below 80 under the blowing of N2 to agitate the sample solution. The Rh compound precipitated from the addition of an NaOH solution to alkalize the H3RhCl6 solution. This compound showed some sharp X-ray diffraction lines, but they could not be identified. The precipitation ratio was measured by ICP analysis for Rh concentration of the filtrate. The ratio for precipitation time of 15 minutes was considered to be the equilibrium value because the ratio did not change after 15 minutes. It was clarified from the relation between the equilibrium ratio and the concentration of added NaOH solution that all of the Rh in the solution was precipitated in the case of a concentration above 0.5 mol/l. The values of the precipitation ratio were hardly affected by precipitation temperatures between 20 and 80°C. After the treatment completed precipitation of Rh in the solution, an N2H4 solution was added to the solution and reduced the compound to metal Rh. It was shown by SEM observation and measurement of the particle size distribution of the filtrated solid that distinction between the Rh compound and metal Rh was very difficult in terms of shape and size. The particles had the diameter of 0.05 ∼ 0.1μm and partly aggregated. The reduction ratio was measured from the analysis of the Rh compound in a filtrated solid because the compound was easy to dissolve in acid. However, metal Rh was difficult to dissolve by such an aqua regia. The reduction curves were obtained from reduction behavior with the reduction time in the temperature range of 60 ∼ 80°C. The initial reaction rate was obtained from the initial straight line of the reaction curve. The temperature dependency of the rate gave 96 kJ/mol as the activation energy of the reduction. Consequently, it was considered that the reduction was rate-determined by the chemical reaction.

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Barium titanium sulfide, BaxTiSy with various x and y values, i. e. x = 0.6 ∼ 0.81 and y = 2.89 ∼ 3.82, has been synthesized by the reaction of BaS and TiS2 in sulfur melt at temperatures between 350 and 450 °C. The unreacted solvent sulfur was completely removed by two-step separation method after reaction. The results showed that the x value of BaxTiSy tended to increase with increasing heating temperature and heating time and the maximum x value was around 0.8. The y values were around 3.0 at 400 and 450 °C. The addition of 10 mol % BaCl2 was found to expedite greatly the yield of reaction to form BaxTiSy especially at higher heating temperature of 450 °C. The BaCl2 and BaS3 impurities were removed by treating with water. This treatment was also effected to change some X-ray peak positions of BaxTiSy prepared by the present low temperature method.

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