Yang, Shengchang
Feng, Ting
Li, Dong
Wen, Di
Yang, Chenteng
Ma, Chunling
Cong, Bin
Funding for this research was provided by:
Natural Science Foundation of China (81172900)
Applied Basic Research Key Program of Hebei Province (10966911D)
Natural Science Foundation of Hebei Province (C2007000826)