1. Spectroscopy Department, Physics Division; National Research Centre; Cairo Egypt
2. Physics Department, Faculty of science; Taif University; Taif Kingdom of Saudi Arabia
3. Physics Department, Faculty of Science; Ain Shams University; Cairo Egypt
4. Synchrotron-light for Experimental and Scientific Applications in the Middle East; Allan Jordan
5. Air pollution Research Department; National Research Centre, Dokki; Cairo Egypt