作者机构:[1]Institute of Applied Chemistry, China West Normal University, Nanchong 637002, China, [2]Department of Materials Science, Sichuan University, Chengdu 610064, China
相关基金:Acknowledgements This project was supported by the National Natural Science Foundation of China (No. 50572066), the Sichuan Provincial Department of Education, China (No. 2006A075) and the Doctor Start-up Foundation of China West Normal University (No. 06B059).