国家自然科学基金(30571552);郑州市科技攻关项目(052SGYS33210);河南省自然科学基金(0611044900).
Supported by National Natural Science Foundation of China(30571552),the Key Science and Technique Foundation Program of Zhengzhou city(052SGYS33210) and Natural Science Foundation of Henan Province)(0611044900).