#SR-ATR-FTIR
    
    
    
                        
            
            Siwatt Pongpiachan* School of Social and Environmental Development, National Institute of Development Administration (NIDA); Kanjana Thumanu; Chulalak Chantharakhon; Chunmanus Phoomalee; Chaisri Tharasawatpipat; Ronbanchob Apiratikul; Saran Poshyachinda