基金National Natural Science Foundation of China (60674036, 60974003), the Natural Science Foundation for Distinguished Young Scholar of Shandong Province of China (JQ200919), the Program for New Century Excellent Talents in University of China (NCET-07-0513), the Key Science and Technique Foundation of Ministry of Education of China (108079), the Excellent Young and Middle-Aged Scientist Award Grant of Shandong Province of China (2007BS01010)