1. Institute for Chemical Reaction Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
2. Process Technology Research Laboratories, Nippon Steel Corp., 20-1 Shintomi, Futtsu, Chiba 293-0011, Japan
3. Materials and Processing Research Center, NKK., 1 Kokan-cho, Fukuyama, Hiroshima 721-8510, Japan