PetroChina Changqing Oilfield Company;
Oil Production Plant No. 1;
Yanan 716000;
China;
Key Laboratory for Hydrocarbon Accumulation;
Ministry of Education;
Faculty of Natural Resources & Information Technology;
China University of Petroleum;
Beifing 102249;
China;
School of Environment;
Beifing Normal University;
Beijing 100875;
China;