1. Research Institute of Enhanced Oil Recovery, China University of Petroleum (Beijing), Beijing 102249, P. R. China
2. China University of Petroleum-Beijing att Karamay, Karamay, Xinjiang 834000, P. R. China
3. Department of Geosciences and Geological and Petroleum Engineering, Missouri University of Science and Technology, Rolla, Missouri 65401, United States
4. School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, P. R. China