柯林斯词典berkelium /bɜːˈkiːlɪəm, ˈbɜːklɪəm/ 1. N a metallic transuranic element produced by bombardment of americium. Symbol: Bk; atomic no: 97; half-life of most stable isotope, 247Bk: 1400 years; valency: 3 or 4; relative density: 14 (est) 錇 返回 berkelium