二环的英文：
bicyclo
- Bridged bicyclooctanes gave no significant bridgehead substitution
桥二环辛烷不给出有意义的桥头取代。 - Half of the Erhuang Road are hot islands; experts suggest cooling.
北京二环内一半是热岛专家提出冷却建议 - Adamantane and bicyclo (222) octane are predominantly Chlorinated at the bridgeheads by this procedure
金刚烷和二环〔222〕辛烷主要是按照这个程序在桥头氯化。
n.二环
- Adamantane and bicyclo (222) octane are predominantly Chlorinated at the bridgeheads by this procedure
金刚烷和二环〔222〕辛烷主要是按照这个程序在桥头氯化。