1. School of Materials Science and Chemical Engineering Ningbo University Fenghua road 818 Ningbo Zhejiang 315211 P. R. China
2. Department of Applied Chemistry Hiroshima Hiroshima University Higashi Hiroshima 739-8527 Japan
3. Faculty of Engineering Kanagawa University Rokkakubashi, Kanagawa-ku Yokohama 2218686 Japan