1. Department of Advanced Fibro-Science, Kyoto Institute of Technology, Matsugasaki, Kyoto 606-8585, JAPAN
2. Energy Technology Laboratories, Osaka Gas Co Ltd., 6-19-9, Torishima, Konohana-ku, Osaka 554-0051, Japan
3. Faculty of Fiber Science and Engineering, Kyoto Institute of Technology, Matsugasaki, Kyoto 606-8585, Japan