1. Osaka National Research Institute, AIST, 1-8-31, Midorigaoka, Ikeda, Osaka, 563, Japan, Department of Applied Chemistry, Faculty of Engineering, Osaka Institute of Technology, 5-16-1, Ohmiya, Asahi-ku, Osaka, 535, Japan, and Research Institute of Innovative Technology for the Earth, 9-2, Kizugawadai, Kizucho, Soraku-gun, Kyoto, 619-02, Japan