1. Division of Applied Chemistry and Biochemistry, National Institute of Technology, Tomakomai College, Nishikioka 443, Tomakomai, Hokkaido 059 1275, Japan
2. Kusano Sakko Inc., Nishimachi 16, Kamiebetsu, Ebetsu, Hokkaido 067 0063, Japan
3. Faculty of Engineering, Hokkaido University, N13W8, Kita-ku, Sapporo, Hokkaido 060 8628, Japan