1. Department of Applied Chemistry,
Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
2. Japan Atomic Energy Agency, Takasaki Advanced Radiation Research Institute, 1233
Watanuki-machi, Takasaki, Gunma 370-1292, Japan
3. Institute of Multidisciplinary
Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan