[1] Northern Border Univ, Coll Sci, Dept Phys, Ar Ar, Saudi Arabia
[2] Sudan Univ Sci & Technol, Fac Sci, Dept Phys, Khartoum, Sudan
[3] Univ South Africa, Coll Grad Studies, UNESCO UNISA Africa Chair Nanosci & Nanotechnol La, POB 392, ZA-0003 Pretoria, South Africa
[4] Natl Res Fdn, Mat Res Dept, iThemba LABS, POB 722, ZA-7129 Cape Town, South Africa
[5] Univ Western Cape, Dept Med Biosci, Private Bag X17, ZA-7535 Bellville, South Africa
[6] Cape Peninsula Univ Technol, Fac Hlth & Wellness Sci, POB 1906, ZA-7535 Bellville, South Africa
[7] Northern Border Univ, Ctr Sci Res & Entrepreneurship, Ar Ar, Saudi Arabia
[8] Abdus Salam Int Ctr Theoret Phys UNESCO, Multidisciplinary Lab, Via Beirut 31, I-34014 Trieste, Italy