出典:Wiktionary
出典:『Wiktionary』 (2026/04/25 00:20 UTC 版)
| Chemical element |
|---|
| Fm Atomic number 100 fermium |
| Previous: ← einsteinium (Es) |
| Next: mendelevium (Md) → |
| English Wikipedia article on Fermium |
| Chemical element |
|---|
| Fm Atomic number 100 fermium |
| Previous: ← einsteinium (Es) |
| Next: mendelevium (Md) → |
Named after Italian physicist Enrico Fermi (1901–1954).
Derived from Fermi + -ium (chemical element suffix). For the surname see Fermi.
出典:Wikipedia
出典:『Wikipedia』 (2011/06/21 18:54 UTC 版)
Fermium (
/ˈfɜrmiəm/ fur-mee-əm) is a synthetic element with the symbol Fm. It is the 100th element in the periodic table and a member of the actinide series. It is the heaviest element that can be formed by neutron bombardment of lighter elements, and hence the last element that can be prepared in macroscopic quantities, although fermium metal has not yet been prepared. A total of 19 isotopes are known, with 257Fm being the longest-lived one with a half-life of 100.5 days.
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