1. Faculty of Chemical Engineering Technology, Universiti Malaysia Perlis (UniMAP), Perlis, Malaysia; Geopolymer & Green Technology, Centre of Excellent (CEGeoGTech) , Universiti Malaysia Perlis (UniMAP) , Perlis , Malaysia
2. School of Materials and Mineral Resources Engineering, Engineering Campus, Universiti Sains Malaysia , 14300 Nibong Tebal , Pulau Pinang , Malaysia
3. School of Aerospace Engineering, Engineering Campus, Universiti Sains Malaysia , 14300 Nibong Tebal , Pulau Pinang , Malaysia
4. School of Chemical Sciences, Universiti Sains Malaysia , 11800 Minden , Penang , Malaysia