1. Department of Chemistry, Faculty of Science, Kasetsart University 50 Phahonyothin, Chatuchak, Bangkok, 10903, Thailand
2. Lehrstuhl für Umweltmesstechnik, Universität Karlsruhe D-76128, Karlsruhe, Germany
3. National Synchrotron Research Center, P.O. Box 93, Nakhon-Ratchasima, 30000, Thailand
4. School of Physics, Suranaree University of Technology, Nakhon-Ratchasima, 30000, Thailand