The hardness and tensile properties of Mg–La–Zr alloys with various lanthanum contents were investigated, and the microstructures of the alloys were examined. The microstructure was composed of fine globular primary αMg grains and eutectic areas. The values of yield stress and modulus of the eutectic were, respectively, about 3 times and 1.7 times higher than those of the primary αMg. The increase in the yield stress of the alloys with less than 1.2%La is due to a rapid increase in coverage of the αMg grain boundary by the eutectic. As the increment in the grain boundary coverage decreases with lanthanum content, the composite strengthening (composite materials effect) starts to play a more significant role in increasing yield stress. As the grain boundary coverage reaches a plateau at about 2%La, further increase in the yield stress is mainly due to the composite strengthening, the effect of which is dependent on the volume fraction of eutectic. During tensile-testing at 150°C, the alloys with higher lanthanum content exhibited dual yield points, the first from yielding of the primary αMg, followed by the higher-yield point associated with the eutectic. This suggests that composite strengthening is in effect.

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This paper describes uniaxial cyclic elastic follow-up tests carried out on austenitic stainless steel SUS 304 at 700°C, and analyses of the test results. In the present tests, more of the starting points of elastic follow-up strain were beyond the elastic limit of the material. The analysis for stress and strain behavior which progressed under uniaxial elastic follow-up tests was performed by similar methods proposed in the previous paper. The stress and strain in the cyclic elastic follow-up process were estimated by an inelastic analysis based on Norton's law applied to a modified triangle of elastic follow-up. The agreement of the analysis and the experiment was very good. The plastic strain range, produced in the hysteresis loop, depended upon the stress which was elastically calculated on the triangle of elastic follow-up. The cyclic elastic follow-up behavior could also be estimated conservatively from the inelastic analysis.

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2006年に閣議決定された第3期科学技術基本計画において「国民との科学技術対話」が盛り込まれ，高等教育機関では科学コミュニケーターの養成が活発化した．東京海洋大学では2007年より水圏環境リテラシー教育推進プログラムを立ち上げ，海洋を含めた水圏に関する科学技術対話を促進させる役割を担う水圏環境教育推進リーダーの養成に取り組み，水圏環境教育の理念に基づいた水圏環境リテラシーの普及を行ってきた．水圏環境教育は「観察，思考，理解，決定と行動，伝達」できる市民の育成と対等に対話して学び合う協働的なネットワークの構築を目指しており，国連の持続可能な目標SDGs を達成する上で成果が期待される．本稿では，水圏環境リテラシー教育推進プログラムのこれまでの成果と今後の課題について報告する．

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  Because Japan is an island country, it presents possibilities for the establishment of an energy-saving, cyclical society by fostering intrinsically motivated communities based on the forest‒river‒ocean relationship. To establish such a society, learning and educational theory must emphasize forest‒river‒ocean-based learning communities and uniting cities and villages in watershed areas. This study was conducted to clarify the dialog processes at program development meetings that particularly discuss the forest‒river‒ocean and human relationship in tsunami disaster areas. Results show that the development process of dialog consists of problem presentation, followed by sharing of understanding, critical opinions, self-reflection, creative ideas, support, approving opinions of creative ideas, and finally, a summarization of opinions. Participants’ creativity developed along the dialogue stages, advancing relatedness, competence, and autonomy analyzed by self-determination theory and learning cycle theory. Furthermore, the leading group served an important role as a facilitator in fostering autonomy and creativity.

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