1. Department of Chemical Engineering, National Cheng Kung University, No.1, Tainan, 701-01, Taiwan
2. Department of Chemical and Materials Engineering, National University of Kaohsiung, No. 700, Kaohsiung University Rd., Nan-Tzu Dist, Kaohsiung, 811, Taiwan
3. Department of Materials Science and Engineering, Feng Chia University, Taichung, 407-24, Taiwan