National Natural Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [41023001, 41101413, 41001260, 41101407, 41071261]; National Technology Support Project [2011BAB01B01, 2012BAH28B04]; PhD Program Foundation of Ministry of Education of ChinaMinistry of Education, China [20110141120073]; 863 ProgramNational High Technology Research and Development Program of China [2012AA12A304, 2012AA12A306]