1. Department of Physics Graduate School of Science, Osaka University, Toyonaka, Osaka 560, Japan
2. Department of Chemistry, Same Graduate School
3. Faculty of Engineering, Gunma University, Kiryu, Gunma 376, Japan
4. Wakasa Institute of Energy Development, Tokyo; Tsuruga 914, Japan
5. Cyclotron and Radio Isotope Center, Aoba, Aramaki, Sendai 980-77, Japan
6. Kochi University of Technology, Tosayamada, Kochi 782, Japan