1. College of Art, Taiyuan University of Technology, 209 University Avenue, Jinzhong, Shanxi 030600, China
2. Department of Mechanical and Mechanics, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University AVE West, Waterloo, ON, Canada N2L 3G1
3. Institute of Resources and Environmental Engineering, Shanxi University, 92 Wucheng Road, Taiyuan 030006, China