1. Physics and Chemistry Testing and Research Division, Yokohama City Institute of Public Health, 2-7-1 Tomiokahigashi, Kanazawa-ku, Yokohama, Kanagawa 236-0051, Japan
2. Mechanical and Material Engineering Division, Kanagawa Industrial Technology Center, 705-1 Shimo-imaizumi, Ebina, Kanagawa 243-0435, Japan