1. Department of Chemistry, Faculty of Education, Ain Shams University, Roxy, Cairo, Egypt
2. Department of Chemistry, Faculty of Science, King Khalid University, P. O. Box 9004, Abha 61321, Saudi Arabia
3. Department of Chemistry, Faculty of Science (Men's Campus), Al-Azhar University, Nasr City 11884, Cairo, Egypt
4. Physics Department, Faculty of Education, Ain Shams University, Roxy, Cairo, Egypt