1. School of Petroleum Engineering, Changzhou University, Changzhou 213164, P. R. China
2. China Petroleum Technology & Development Corporation, Chaoyang District, Beijing 100028, P. R. China
3. College of engineering, Zunyi Normal University, Zunyi 563006, P. R. China
4. School of Petroleum Engineering, Yangtze University, Wuhan 434023, P. R. China
5. School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, P. R. China