Funding for this research was provided by:
National Natural Science Foundation of China (61271172 and 61372085)
RFDP (20120185110030, 20130185130002 and 20120185110025)
SRF for ROCS, SEM 863 high technology plan (SRF for ROCS, SEM 863 high technology plan)
Sichuan International Corporation Project (2013HH0005)