Caserones is the first world class copper mine owned and operated 100% by Japanese companies. It is an open pit mine located in the Andes, 160 km southeast of the city of Copiapó, Chile. The equity is shared by 2 Japanese companies, Pan Pacific Copper CO., LTD and Mitsui & CO., LTD. In May 2006, Pan Pacific Copper acquired the concession which includes Caserones as a supergene oxide and sulphide copper prospect. In pre-feasibility study stage, a significant hypogene sulfide ore was identified beneath it. The construction began in March 2010, and the SX-EW plant started operation in March 2013. In July 2014, at the beginning of copper concentrates production, the official opening ceremony was held in Santiago of Chile, with the attendance of Japanese Prime Minister Shinzo Abe and Chilean Mining Minister Aurora Williams. Caserones is estimated to embrace 1 billion tons of hypogene ore containing 0.34% of copper and 126ppm of molybdenum, besides 300 million tons of supergene ore with 0.25% of copper. The production is planned to last 28 years. Caserones will contribute to the stability of copper supply to Japan, as well to raising Japanese mining experts.

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Global demands for minerals keep increasing and securing the stable supply remains huge concern for us. In addition, the supply chain structure has dramatically changed during the last decade or two and this also affects our resource security. In this paper, we chose the copper industry as a case study and applied social network analysis (SNA) to corporate ownership information and international trade data. With the help of SNA, the change of ownership structure behind the physical/monetary flows of copper was visualized and analyzed quantitatively. From the analysis for ownership information, we found out mining majors had increased their presence in the industry, while Japanese companies changed their approach and increase their relationship to the whole structure of the industry, which will contribute to stabilize Japanese copper raw material supply. Combining both ownership and trade flow analysis, China also increased its presence in the trade flows. However, in the case of ownership network, their presence as a group is not as large as it is in the case of trade flows. However, PageRank showed that the State of China is already one of the biggest entity in the industry, which might reflect its resource policy.

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Extraction behavior of cobalt from sulfate media containing excess manganese by mixtures of several carboxylic acids and LIX63 in diluent was investigated. The addition of carboxylic acids shifts cobalt extraction isotherm to lower pH region. The degree of the pH isotherm shifts (ΔpH0.5) depends on the dissociation constant (pKa) of carboxylic acids. The steric hindrance affects little for cobalt extraction isotherm in case of carboxylic acid addition. According to relationship between cobalt distribution ratio and extractant concentration and between cobalt distribution ratio and pH, LIX63 extracts cobalt from an aqueous phase and the carboxylic acid affects the proton release from LIX63.

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酸素発生用RuO₂-Ta₂O₅ 触媒層 (Ru=30 mol%) を熱分解法により260℃，300℃，500℃で作製し，その結晶構造，表面形態，電気化学特性をX 線回折，SEM, サイクリックボルタメトリー，クロノポテンショメトリーで研究した。X 線回折およびSEM による結果から，触媒層中のRuO₂ は温度が低くなると結晶性が低下し，260℃では非晶質化が生じることが明らかになった。非晶質の触媒層では，二重層の充電電気量の増加とともに硫酸浴中での酸素発生が促進され，非晶質のIrO₂-Ta₂O₅ 触媒層よりも低い酸素発生電位を示した。

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