1. School of Energy and Power Engineering, Changchun Institute of Technology, Changchun, Jilin 130012, P. R. China
2. Department of Applied Mathematics, Faculty of Mathematical Sciences, University of Tabriz, Tabriz, Iran
3. Natural Sciences Faculty, Lankaran State University, 50 H. Aslanov Street, Lankaran, Azerbaijan
4. Department of Physics, Payame Noor University, P. O. Box 19395-4697, Tehran, Iran
5. Department of Physics, University College — Khurma, Taif University, P. O. Box 11099, Taif 21944, Saudi Arabia
6. Department of Medical Laboratory Techniques, College of Medical Technology, Al-Farahidi University, Baghdad, Iraq
7. Department of Medical Laboratories Technology, Al-Nisour University College, Baghdad, Iraq
8. Department of Mathematics, Faculty of Education, Erciyes University, 38039 Melikgazi-Kayseri, Turkey