1. Electronic Materials Research Department, Advanced Technology and New Materials Research Institute, City of Scientific Research and Technological Applications (SRTA-City), P.O. Box 21934, New Borg El-Arab City, Alexandria 21934, Egypt
2. Nanotechnology Dept. Environmental Studies and Research Institute (ESRI), University of Sadat City, Minofiya 32897, Egypt
3. Institute of Graduate Studies and Research, Alexandria University, 163 Horrya Avenue, P.O. Box 832, Shatby, Alexandria 21526, Egypt