基金Supported by the National Natural Science Foundation of China under Grant No.60473075 (国家自然科学基金)the Key Program of the National Natural Science Foundation of China under Grant No.60533110 (国家自然基金重点项目)+1 种基金the National Basic Research Program of China under Grant No.2006CB303000 (国家重点基础研究发展计划(973))the Heilongjiang Province Fund for Young Scholars of China under Grant No.QC06C033 (黑龙江省青年科技专项资金)