Chen, Jie
Liu, Cheng-Fu
Yang, Cheng-Wen
Zeng, Cheng-Chu
Liu, Wei
Hu, Li-Ming
Funding for this research was provided by:
Beijing Natural Science Foundation (7112008)
Beijing City Education Committee (KM201010005009)
Article History
Received: 23 September 2014
Accepted: 16 January 2015
First Online: 5 March 2015