The Japanese frameworks of the supply and demand for rare metals are very fragile. Examining the volatile market for rare metals since 1980, we can see two different factors causing the collapse of the market balance. The first is the rapid growth of high-tech industries in developed countries. Recently the prices of Ta and In raised more than five times compared with usual price. They were caused by temporary imbalance between the rapid burst of consumptions of mobile phone (tantalum capacitor) and liquid crystal television (flat panel display) and speed up production in conjunction with the rise in demand. Other similar volatile markets often occurred. The second is the resource nationalism in developing countries. For example, China accounts for 97% of world's rare-earth production, and it controls the global market. Rare earth prices are continuing to rise since 2010 by Chinese stringent quotas. Especially the rises in terbium and europium prices have been staggering.
This article proposes as follows.
1) First, the short-term (0-5 year period) strategy for rare metals focused both on supply and demand side is framed. Based on this strategy new supply lines must be carried on.
2) Considering extremely uneven metal productions it is necessary to diversify rare metals sources in order to lessen the high degree of dependence. Chinese shares of many commodities such as tantalum, bismuth, indium and silicon exceed 50% of world production. Most of platinum and palladium were produced from two countries, South Africa and Russia. About 50% of cobalt production depends on Dispute place Copper Belt. Occasionally, diversification has more important priority than cost benefit.
3) It is essential to create a new strengthen organization to carry out the strategy for securing rare metals in Japan mentioned above. The organization is needed to integrate the systems of raw material--intermediate product--finished product.

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The degree to which a rock abrades a cutting tool or a bit is called its "abrasivity". CERCHAR test developed by Centre d'Études et Recherches des Charbonnages de France is widely used to examine rock abrasivity especially in France in the coal mining industry. In this study, a portable CERCHAR tester was developed for in-situ test. Mass of the tester is less than 1 kg and one person can easily handle the tester. Both portable and conventional CERCHAR tests were conducted with 19 rocks. Reasonable correlation was found between the abrasivity indices of two CERCHAR tests. The abrasivity indices measured by the portable tester were slightly larger than those by the conventional tester. The higher scratching speed in the portable tester led to the higher stylus tip temperature and then the higher wear than those in the conventional tester.

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The purpose of this study was to clarify the relationship between irregular lump point load strength (PLS) and uniaxial compressive strength (UCS) in hydrothermally altered and least altered rocks, which are typical of the soft and semi-hard rocks found in northeastern Hokkaido, Japan. The numbers of specimens tested were 2,710 rock specimens for the irregular lump PLS test, whereas 312 rock specimens for the UCS test. These came primarily from the earth's surface in ancient hydrothermal fields. The rock specimens underwent irregular lump PLS and UCS tests using a laboratory testing machine with specimens.
The correlations between the irregular lump PLS, which was calculated by the formula of Hiramatsu et al. (1965), and the UCS were linear. The relationships between irregular lump PLS (I_s(i)) and UCS (q_u) were q_u = 5.3-5.4 I_s(i), in the soft and semi-hard rocks with an irregular lump PLS below 8 MPa. These relationships applied to on-site tests of rocks with natural-moist state. The number of tested specimens satisfied accuracy requirements, based on the coefficient of variation. The irregular lump PLS was strongly correlated with the UCS. Therefore, the relationships between irregular lump PLS and UCS established in this study were highly precise. We could calculate the UCS from irregular lump PLS tests in the soft and semi-hard rocks only when their irregular lump PLS below 8 MPa.

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To evaluate durability of high early strength Portland cement (HES) and alumina cement (AL) mortars for sulfate attack, wetting-drying experiment was carried out. The cylindrical specimens with a size of 35 mm in diameter and 70 mm in height and seawater and saturated sodium sulfate solution at 20°C were used for the experiments. Immersion at 20°C for 2 hours, oven-drying at 40°C for 20 hours, cooling at 20°C for 2 hours, and these wetting-drying procedures were repeated for up to 35 cycles. Equotip hardness and unconfined compressive strength (UCS) of specimens were tested at intervals of several cycles. UCS of specimen decreased at first, which was followed by the drop in surface hardness to a lower value. Decrease of UCS in both mortals was attributed to sub-efflorescence (salt crystallization beneath the surface), and apparent reduction of surface hardness in HES was caused by counter scaling with efflorescence (salt crystallization at the surface). The HES mortal with many micropores (< 0.1 μm in radius) highly deteriorated rather than AL mortal which has pores larger than 0.1 μm in radius. Physical and chemical properties of mortals were due to the induction of sodium sulfate attack, which was attributed to the strength reduction of its own.

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本研究の目的は，熱帯植物Moringa oleiferaから抽出した成分を凝集剤として用いた「モリンガ凝集沈殿 ? 緩速砂ろ過」システムを構築し，1) 人工カオリン濁水 (280NTU) を処理すること，そして2) 凝集沈殿処理後の上澄み液に残存するモリンガ凝集剤を砂ろ過処理で除去することで生物学的に不活性な処理水を生産することである。検討した処理因子は，モリンガ凝集剤の注入量，緩速攪拌速度，緩速攪拌時間，砂の大きさ，そしてろ過速度である。
　最適化された凝集沈澱処理条件下では上澄みの残存濁度は30NTUとなり，約90％の濁度除去が達成された。この上澄み液の濁度は緩速砂ろ過でさらに除去され，最適砂ろ過条件下では45日間の実験期間を通して0．5NTU以下に保たれた。さらに，緩速砂ろ過処理により有機炭素除去率は効果的 (処理条件によって異なり最高除去率は70～90％) に除去されることがわかった。しかし，小さい砂 (有効径0.35mm) を用いた場合は砂の中で微生物が過多に繁殖して処理水質が悪化したため，緩速砂ろ過処理の条件を決定する際には十分な注意が必要であることが示唆された。

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The effect of α-nitroso-β-naphthol on the deposition behavior and the surface morphology of Zn from electrowinning solutions has been investigated by measuring polarization curves for Zn deposition, the time-dependence of cathode potential during electrolysis and the crystal orientation of Zn. α-nitroso-β-naphthol acted as a polarizer for Zn deposition and as a depolarizer for hydrogen evolution on Zn cathode to shift the cathode potential. In solution containing 100mg/L of α-nitroso-β-naphthol, Zn repeated the deposition and dissolution. The α-nitroso-β-naphthol accelerated the hydrogen evolution on Zn, showing that the dissolution of deposited Zn was attributed to the catalysis of α-nitroso-β-naphthol for hydrogen evolution. Zn deposited from α-nitroso-β-naphthol-free solution showed preferred orientation of {10-11} plane and Zn platelet crystals inclined to the substrate, while Zn deposited from solutions containing 1 to 10 mg/L of α-nitroso-β-naphthol showed preferred orientation of {0001} and {10-13} planes and Zn platelet crystals became parallel to the substrate. In solutions containing 50 to 100 mg/L of α-nitroso-β-naphthol, the preferred orientation of Zn was {10-10} and Zn was composed of the styloid crystals without platelet. The current efficiency for Zn deposition decreased with increasing the concentration of α-nitroso-β-naphthol in solution.

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Electrocatalytic properties of Pt oxide blacks reduced in H₂ atmosphere at 323-873 K have been investigated by rotating disk electrode method for the purpose of inventing a novel anode catalyst for DMFC. Specific surface area measurement of active site by CO stripping voltammetry, analysis of chemical bonding energy by XPS and determination of O/Pt atomic ratio by EPMA were also carried out about the Pt oxide blacks reduced at various temperatures. Compared with the untreated Pt oxide black, the methanol oxidation activity of Pt oxide black was significantly improved by hydrogen reduction at 323-373 K. The Pt oxide black reduced especially at 373 K had good properties, namely the anode catalyst showed both the minimum activation energy and the largest current density of methanol oxidation. However, the methanol oxidation activity of the Pt oxide black fell by contraries, in the case the high temperature reduction was carried out in the range of 673-873 K. The Pt oxide black reduced at 373 K showed the largest specific surface area of active site and the lowest atomic ratio of O/Pt in all the anode catalysts. Therefore, the specific surface area of active sites, which can be determined by CO stripping voltammetry, has a close relation to the methanol oxidation activity of the anode catalyst. This study confirmed that the methanol oxidation activity of the Pt oxide black, which effectually treated by hydrogen reduction, exceeded that of the anode catalyst now in use or PtRu black. Since an excellent CO oxidization activity can be recognized, the partially reduced Pt oxide black is also expected as a hyperactive anode catalyst of the fuel cell using other fuels with high concentration CO besides methanol.

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