1. State Key Laboratory of Fluorine & Nitrogen Chemicals, Xi’an Modern Chemistry Research Institute, Xi’an 710065 P. R. China
2. China Northern Industry Co., Ltd., Beijing 100089 P. R. China
3. Department of Applied Chemistry School of Science, Northwestern Polytechnical University, Xi’an 710129 P. R. China
4. Science and Technology on Combustion, Thermostructure and Internal Flow Laboratory, Northwestern Polytechnical University, Xi’an 710129 P. R. China