The National Natural Science Foundation of China(No.31093430,31170360);Program for New Century Excellent Talents in Universities of China(No.NCET-10-0691)
supported by the National Natural Science Foundation of China (Grant No. 30671691);the National Science Foundation for Post-doctoral Scientists of China (44th);the Foundation for Outstanding Young Faculty Members of Northwest A&F University
The Natural Science Foundation of China(Grant No.30671691);the National Science Foundation for Post-doctoral Scientists of China and the Foundation for Outstanding Young Faculty Members of Northwest A&F University