Perfluoro-1,2-dimethylcyclobutanePerfluoro(dimethylcyclobutane) 97%全氟-1,2-二甲基环丁烷(顺反异构体混合物)1,1,2,2,3,4-Hexafluoro-3,4-bis(trifluoromethyl)cyclobutane, mixture of cis and transPerfluoro-1,2-dimethylcyclobutaneDodecafluorodimethylcyclobutane全氟-1,2-二甲基环丁烷