[yoo-nil-kwod-ee-uh
m] 
| Chemistry, Physics. provisional name for the transuranic element with atomic number 104. Symbol: Unq |
| un·nil·quad·i·um (yōō'nĭl-kwŏd'ē-əm) n. See rutherfordium. [Latin ūnus, one; see union + nīl, nothing; see nil + quad(ri)- + -ium.] |
unnilquadium
an artificially produced radioactive transuranium element in Group IVb of the periodic table, atomic number 104. Soviet scientists at the Joint Institute for Nuclear Research at Dubna, Russia, U.S.S.R., announced in 1964 the discovery of element 104, which they named kurchatovium, symbol Ku (for Igor Kurchatov, a Soviet nuclear physicist). In 1969, a group of American researchers at the Lawrence Radiation Laboratory of the University of California at Berkeley announced that they had identified isotopes of the element, different from the one identified by the Soviets; the Americans then proposed the name rutherfordium, in honour of the British physicist Ernest Rutherford
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