Project of National Natural Science Foundation of China(50872077);Basic Project Supported by the Program of Shaanxi Natural Science(2010JM6013);Project of National Youth Science Foundation(51002092);the Graduate Innovation Found of Shaanxi University of Science and Technology(SUST-A04);the R&D Innovation Team Assistance Fund(TD09-05)
National Natural Science Foundation of China(50872077);Natural Science Foundation Research Project of Shaanxi Province(SJ08E104,2010JM6013);Foundation of Shaanxi University of Science and Technology(SUST-A04,ZX08-11)