Americium

2 definitions found

From WordNet (r) 2.0 [wn]:

  americium
       n : a radioactive transuranic metallic element; discovered by
           bombarding uranium with helium atoms [syn: {Am}, {atomic
           number 95}]

From Elements database 20001107 [elements]:



  americium
  Symbol: Am
  Atomic number: 95
  Atomic weight: (243)
  Radioactive metallic transuranic element, belongs to the actinoids. Ten
  known isotopes. Am-243 is the most stable isotope, with a half-life of
  7.95*10^3 years. Discovered by Glenn T. Seaborg and associates in 1945, it
  was obtained by bombarding {uranium}-238 with alpha particles.