د.هلال اسماعيل عبدالرحمن علي

   Dr. Helal Ismaeil Abdel-Rahman ali                 Asistant Professor

   Natural and Applied Sciences Department 

  Al-Aflaj Community College, King Saud Univeresity

  Office: +96616826600 Ex. 207   Fax:+96616826194

   Email: halia@ksu.edu.sa, helal_ismaeil@yahoo.com

  al-Aflaj city, Saudi Arabia Kingdom