| 释义 |
pro·me·thi·um AHD[prə-mēʹthē-əm] D.J.[prəˈmiːθiːəm]K.K.[prəˈmiθiəm]n.Symbol Pm （名词）符号 Pm - A radioactive rare-earth element prepared by fission of uranium or by neutron bombardment of neodymium, having 14 isotopes with mass numbers ranging from 141 to 154 and used as a source of beta rays. Atomic number 61; melting point 1,168°C; boiling point 2,460°C; valence 3. See table at element 钜：放射性稀土元素，由铀分裂或钛的中子爆炸而成，有十四个拥有从141到154的质量数的同位素，用作β射线源。原子序数61；熔点1,168°C；沸点2,460°C；原子价为3 参见 element
- From Prometheus 源自 Prometheus
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