[1] Univ Sci & Technol China, CAS Ctr Excellence Nanosci, Natl Synchrotron Radiat Lab, Hefei 230029, Anhui, Peoples R China
[2] King Fahd Univ Petr & Minerals, Phys Dept, Dhahran 31261, Saudi Arabia
[3] King Fahd Univ Petr & Minerals, Ctr Excellence Nanotechnol CENT, Dhahran 31261, Saudi Arabia