1. Program of Science Education, Graduate School, Suratthani Rajabhat University, Surat Thani, Thailand 84100
2. Program of Applied Chemistry, School of Science, Mae Fah Luang University, Chiang Rai, Thailand 57100
3. Program of Chemistry, Faculty of Science and Technology, Pibulsongkram Rajabhat University, Phitsanulok, Thailand 65000
4. Program of Chemistry, Faculty of Science and Technology, Suratthani Rajabhat University, Surat Thani, Thailand 84100