国家自然科学基金No.21107039;辽宁省教育厅科学技术研究项目No.L2011002;辽宁省科学技术计划项目No.2011230009Supported by the National Natural Science Foundation of ChinaNo.21107039,the Science and Technology Research Project of Liaoning Provincial Education DepartmentNo.L2011002 and the Science and Technology Plan Project of Liaoning ProvinceNo.2011230009