fission 核～nuclear fission/军用～物质fissible material for military purposes/自发～ spontaneous fission/ ～材料 fissile materials; fissioner /～产物fission product /～弹fission bomb/～核物质fissionable nuclear material/～武器fission type of weapons/～物质fissionable materials;fissible material/～式原子弹fission bomb