1. Department of Chemical and Materials Engineering, Chang Gung University, Kwei-Shan, Tao-Yuan 333, Taiwan
2. Canadian Light Source Inc., University of Saskatchewan, Saskatoon, Canada S7N 0X4
3. Department of Chemistry, University of Western Ontario, London, Canada N6A 5B7
4. Department of Physics, Tamkang University, Tamsui 251, Taiwan