1. College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, P. R. China
2. Chemistry Metrology Division, Hubei Institute of Measurement and Testing Technology, Wuhan 430200, P. R. China
3. Oil & Gas Technology Research Institute, Changqing Oilfield Company, Xi’an 710018, China
4. National Engineering Laboratory for Exploration and Development of Low-Permeable Oil and Gas Fields, PetroChina Changqing Oilfield Company, Xi’an 710018, China