1. Department of Chemistry, Faculty of Science & Technology, University of Nairobi, Kenya, P.O Box 30197-00100, Nairobi, Kenyaand Materials Testing & Research Division, State Department of Infrastructure, Ministry of Transport and Infrastructure, Housing &Urban Development; P.O. Box 11873 – 00400, Nairobi, Kenya
2. Department of Chemistry, Faculty of Science & Technology, University of Nairobi, Kenya, P.O Box 30197-00100, Nairobi, Kenya
3. Department of Construction and Civil Engineering, University of Nairobi, Kenya, P.O Box 30197-00100, Nairobi, Kenya