Affiliation: | 1.Department of Physics, College of Khurma University College, Taif University, P.O. Box11099, Taif, 21944, Saudi Arabia ;2.Physics Department, Faculty of Science, Al-Azhar University, P O. 71524, Assiut, Egypt ;3.Chemistry Department, Faculty of Science, Al-Azhar University, P.O. 71524, Assiut, Egypt ; |