Ju, Xiuping
Liu, Xiaofang
Gao, Xuejia
Niu, Libo
Feng, Wenhui
Bai, Guoyi
Funding for this research was provided by:
National Natural Science Foundation of China (21376060)
Natural Science Foundation of Hebei Province (CN) (B2014201024)
Natural Science Foundation of Hebei University (2012jq03)