2 0 0 0 OA ゴレンシュタイン多元環の研究
代数幾何学におけるセール双対の理論をネター多元環の場合に拡張し、この概念を用いて、ネター多元環のゴレンシュタイン性の特徴付けを与え、かつ、ゴレンシュタイン多元環上の与えられた傾斜鎖複体に対して、その準同型多元環がまたゴレンシュタイン多元環になるための必要十分条件を与えた。ここで、ネター多元環とは可換ネター環上の多元環で加群として有限生成のものを指し、ゴレンシュタイン多元環とは可換ゴレンシュタイン環上のネター多元環で導来圏における基礎環上の双対が射影的生成素を移動したものと同型になるものを指す。
1 0 0 0 OA くさび形圧子を用いた異方性材料の硬さ測定
- 著者
- 吉川 敬治 加藤 寛 星野 光男
- 出版者
- 公益社団法人 日本材料学会
- 雑誌
- 材料 (ISSN:05145163)
- 巻号頁・発行日
- vol.35, no.399, pp.1431-1437, 1986-12-15 (Released:2009-06-03)
- 参考文献数
- 14
Hardness of carbon fiber reinforced plastics (CFRP) and Al-2 and 4wt% Cu alloys containing columnar grains was measured with a wedge-shaped indenter, and was compared with their static tensile properties. Hardness measurement was conducted with a Rockwell hardness tester. The hardness and mean pressure of CFRP decreased with the angle θ between indentation normal and fiber direction. The orientation dependences of the hardness and the mean pressure agreed with those of Young's modulus and the fracture strength of CFRP. However, no linear relation existed between the mean pressure and the strength. The hardness and the mean pressure of Al-Cu alloys took a minimum when the angle θ was about π/4 rad, and the orientation dependence of the mean pressure disagreed with those of the yield stress and the ultimate tensile strength. The relation between the mean pressure and the yield stress was described by the equation: σy=(P/3)(0.0017)n, where n is the strain hardening coefficient.