Registration No. 7-18 "Application of a low-cost four-LED based photometer...." = 5276
Registration No. 7-19 "A novel way of visualization of the periodic table of the elements" = 4675
Registration No. 7-20 "The Number of Chlorine Atoms in a Molecular Formula...." = 4955
When you click on "Registration No." at each article. This allows you to view detailed statistic data of the article. (Only domain name is written in Japanese.)