1. a Department of Environment and Natural Sciences , Graduate School of Environment and Information Sciences, Yokohama National University, Tokiwadai, Hodogaya-ku , Yokohama, Japan
2. b Research Center, Asahi Glass Co., LTD., Hazawa-cho, Kanagawa-ku , Yokohama, Japan
3. c Material Division, AGC Seimi Chemical Co., LTD., Chigasaki , Japan