1. School of Physics and Optoelectronic Engineering Shandong University of Technology Zibo 255000 P. R. China
2. Institute of Engineering Ceramics School of Materials Science and Engineering Shandong University of Technology Zibo 255000 P. R. China
3. Colin Ratledge Center for Microbial Lipids School of Agricultural Engineering and Food Science Shandong University of Technology Zibo 255000 P. R. China
4. Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and Engineering East China University of Science and Technology Shanghai 200237 P. R. China
5. State Key Laboratory of High Performance Ceramics and Superfine Microstructures Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 P. R. China