fermium(redirected from Unnilnilium)
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a chemical element, atomic number 100, atomic weight 253. (See Appendix 6.)
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
Radioactive element, artificially prepared in 1955, atomic no. 100, atomic wt. 257.095; 257Fm has the longest known half-life (100.5 days) of this transuranium element.
Farlex Partner Medical Dictionary © Farlex 2012
Radioactive element, artificially prepared in 1955; atomic no. 100, atomic wt. 257.095; 257Fm has the longest known half-life (100.5 days).
Medical Dictionary for the Health Professions and Nursing © Farlex 2012