actinium series锕系
actinium family锕族;锕系
actinium lead锕铅;铅的同位素
eka actinium类锕
actinium compound[化学] 锕化合物
actinium group锕系
actinium tricyclopentadienide三锕;三环戊二烯锕
Actinium chloride氯化锕
radio actinium放射锕
N(名词) a radioactive element of the actinide series, occurring as a decay product of uranium. It is used as an alpha-particle source and in neutron production. Symbol: Ac; atomic no: 89; half-life of most stable isotope,227Ac: 21.6 years; relative density: 10.07; melting pt: 1051°C; boiling pt: 3200 ± 300°C 锕