SuppoSed by the National Natural Science Foundation of China under Grant Nos.60673195;60703078(国家自然科学基金);the National High-Tech Research and Development Plan of China under Grant No.2007AA04Z113(国家高技术研究发展计划(863));the National Basic Research Program of China under Grant No.2006CB303105(国家重点基础研究发展规划(973));the National Key Technology R&D Program of China under Grant No.2006BAF01A17(国家科技支撑计划)