Zhang, Peng
Ma, Lulu
Fan, Feifei
Zeng, Zhi
Peng, Cheng
Loya, Phillip E.
Liu, Zheng
Gong, Yongji
Zhang, Jiangnan
Zhang, Xingxiang
Ajayan, Pulickel M.
Zhu, Ting
Lou, Jun
Article History
Received: 18 October 2013
Accepted: 2 April 2014
First Online: 29 April 2014
Competing interests
: The authors declare no competing financial interests.