Funding for this research was provided by:
Major Research Plan of the National Natural Science Foundation of China (91538201)
National Natural Science Foundation of China (61671463, 61571454)
Program for New Century Excellent Talents in University (NCET-11-0872)
Specific fund for Taishan Scholars Project (ts201712072)
Excellent Youth Scholar of the National Defense Science and Technology Foundation of China
Natural Science Foundation of Shandong Province (ZR2017BG014)
Article History
Received: 6 January 2018
Revised: 1 April 2018
Accepted: 27 April 2018
First Online: 7 May 2018