1. Department of Chemistry and Aerosol Science Research Center, National Sun Yat-sen University, Kaohsiung, Taiwan, R.O.C. 80424
2. Department of Chemistry and Biochemistry, National Chung Cheng University, Chiayi, Taiwan, R.O.C. 62102
3. National Synchrotron Radiation Research Center, Hsinchu, Taiwan, R.O.C. 30076