1. Physics Department; Faculty of Science; King Faisal University; Al-Hassa 31982, P.O. Box 400 Saudi Arabia
2. Petroleum Refining; Egyptian Petroleum Research Institute, Nasr City, P.O. Box; 11727 Cairo Egypt
3. Chemical Engineering Department; College of Engineering; King Faisal University; Al-Hassa 31982, P.O. Box 400 Saudi Arabia