1. Universiti Malaysia Perlis, Faculty of Chemical Engineering Technology, Kompleks Pengajian Jejawi 2, 02600 Arau, Perlis, Malaysia
2. Universiti Malaysia Perlis, Geopolymer & Green Technology, Centre of Excellent (CEGeoGTech) Perlis, Malaysia
3. Universiti Sains Malaysia, School of Materials and Mineral Resources Engineering, Engineering Campus, 14300 Nibong Tebal, Pulau Pinang, Malaysia
4. Czestochowa University of Technology, Faculty of Production Engineering and Materials Technology, Department of Physics 42-201 Czestochowa, Poland