from The American Heritage® Dictionary of the English Language, 4th Edition
- n. An artificially produced radioactive element with atomic number 110 and a mass number of 281, whose most stable isotope has a half-life of over one minute. See Table at element.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A transuranic chemical element (symbol Ds) with atomic number 110.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a radioactive transuranic element
Elements 110, 111 and 112 have been named darmstadtium (Ds), roentgenium (Rg) and copernicium (Cn).
Roentgenium, after a modern physicist renamed roentgenium by the General Assembly, was originally discovered in 1994 when a team at GSI created three atoms of the element, about a month after their discovery of darmstadtium, on Dec. 8.
It was created by crashing a heavy isotope of lead with nickel-62, which created four atoms of darmstadtium.
Researchers at Lawrence Berkeley National Laboratory in California saw the isotopes of rutherfordium, seaborgium, hassium, darmstadtium, and copernicium by watching the decay of the yet-to-be-named element 114, a synthetic element first produced about a decade ago.