School of Energy Power and Mechanical Engineering North China Electric Power University Beijing 102206 China;
School of Energy Power and Mechanical Engineering North China Electric Power University Beijing 102206 China;
School of Energy Power and Mechanical Engineering North China Electric Power University Beijing 102206 China;
School of Energy Power and Mechanical Engineering North China Electric Power University Beijing 102206 China;
Crop leaf-surface wax; green additive; synthetic ester; tribological property;