crown diameter measurement in aerial photo
ratio of diameter of labyrinth passage to diameter of particle
18-Crown-6
18-冠-6
18冠6
18-冠醚-6
18–冠<醚>–6
18-Crown-6-tetracarboxylic
4′-acetylaminobenzo[15]crown5
7-Dimethoxy-4-Methene-Coumarin-Monoaza-18-Crown-6