基金This work was supported by the National Natural Science Foundation of China （30872201）, Beijing Municipal project for Developing Advanced Human Resources for Education （BAHED）, the Ph. D. Programs Foundation of Ministry of Education of China （20060025003）, the Research ＆ Development Fund of the Municipal Education Commission of Beijing （KZ200810025009）, and the Project of Beijing Municipal Science ＆ Technology Commission （Z080502036708012）.
Acknowledgement Thank Doctor YANG Ya-Ping for assistance on this work. Doctor YANG Jing and their expert technical
