国家自然科学基金项目No.31170423,31270498,31200474;国家“十二五”科技支撑计划No.2011BAC09B05;四川杰出青年学术与技术带头人培育项目No.2012JQ0008,2012JQ0059 Supported by the National Natural Science Foundation of China No.31170423,31270498,31200474,the National Key Technology R&D Program No.2011BAC09B05 and the Program of Sichuan Youth Sci-tech FoundationNo.2012JQ0008,2012JQ0059