Fierce animals are normally confined to a cage or a compound in the zoo. 动物园里猛兽的活动通常都被限制在一个笼子里或院子里。
The double cage compound C 120 NH was studied by INDO series. The results suggested that the formation of C 120 NH reduce the angle constraint at the three membered ring of imino in C 60 NH, thereby, the C 120 NH is stable. 用INDO系列方法对双笼化合物C120NH进行了理论研究,并预测C120NH的形成缓解了C60NH中亚胺基三元环处的角张力,从而较稳定;