国家自然科学基金资助项目81301050、81271392、81341113;天津市应用基础与前沿技术研究计划资助项目14JCQNJC10200;中国博士后基金项目2013M542583;National Natural Science Foundation of China 81301050,81271392,81341113; Tianjin Research Program of Application Foundation and Advanced Technology 14JCQNJC10200; China Postdoctoral Science Foundation 2013M542583