Supported by by National Natural Science Foundation of China(11071053);the Natural Science Foundation of Hebei Province(A2010001482);the Key Project of Science and Research of Hebei Education Department(ZH2012080)
Supported by the National Natural Science Foundation of China(11071053);the Natural Science Foundation of Hebei Province(A2010001482);the Project of Science and Research of Hebei Education Department(the second round in 2010)