Guo, Yiyou
Ji, Jinsheng
Huo, Hong
Fang, Tao
Li, Deren
Funding for this research was provided by:
Science Fund for Creative Research Groups of the National Natural Science Foundation of China under Grant (61221003)
National Science Foundation of China Youth Program under Grant (41101386)
Article History
Received: 28 November 2017
Accepted: 31 January 2018
First Online: 20 February 2018
Competing interests
: The authors declare that they have no competing interests.
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