1. Graduate School of Science and Technology, Kumamoto University, 2-39-1, Kurokami, Chuo-ku, Kumamoto-shi, Kumamoto 860-8555, Japan.
2. Faculty of Advanced Science and Technology, Kumamoto University, 2-39-1, Kurokami, Chuo-ku, Kumamoto-shi, Kumamoto 860-8555, Japan.
3. Technology and Development Laboratories, Nippon Steel Blast Furnace Slag Cement Co., Ltd., 16, Nishiminato-machi, Kokurakita-ku, Kitakyushu-shi, Fukuoka 803-0801, Japan.