1. College of Chemistry and Environmental Science, Hebei University, Hebei, P. R. China
2. Key Laboratory of Pesticide and Veterinary Drug Monitoring for State Market Regulation/Lanzhou Institute for Food and Drug Control, Gansu, P. R. China
3. Chinese Academy of Inspection and Quarantine, Beijing, P. R. China
4. Gansu Pharmaceutical Group Science and Technology Research Institute Co. Ltd, Gansu, P. R. China