Lu, Chenyang
Jin, Ke
BĂ©land, Laurent K.
Zhang, Feifei
Yang, Taini
Qiao, Liang
Zhang, Yanwen
Bei, Hongbin
Christen, Hans M.
Stoller, Roger E.
Wang, Lumin
Article History
Received: 6 July 2015
Accepted: 22 December 2015
First Online: 1 February 2016
Competing interests
: The authors declare no competing financial interests.