1. Hubei Key Laboratory of Plasma Chemistry and Advanced Materials, Wuhan Institute of Technology, Wuhan 430205, P. R. China
2. National Engineering Laboratory for Exploration and Development of Low-Permeability Oil and Gas Field, Xi’an 710018, P. R. China
3. Oil & Gas Technology Research Institute of Changqing Oil Field Company, Xi’an 710018, P. R. China
4. The Fourth Oil Production Plant of Changqing Oil Field Company, Xi’an 710018, P. R. China
5. Shanxi Ming De Petroleum Technology Limited Company, Xi’an 710018, P. R. China
6. School of Earth Science and Engineering, Xi’an Shiyou University, Xi’an 710065, P. R. China