1. Key Laboratory of Photovoltaic and Energy Conservation Materials; Institute of Applied Technology; Hefei Institutes of Physical Science; Chinese Academy of Sciences; Hefei 230031 China
2. University of Science and Technology of China; Hefei 230026 China
3. Department of Mathematics; Faculty of Science; NAAM Research Group; King Abdulaziz University; Jeddah 21589 Saudi Arabia
4. Department of Mathematics; Quaid-I-Azam University; Islamabad 44000 Pakistan
5. State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources; North China Electric Power University; Beijing 102206 China