dubnium
[doob-nee-uh m, duhb-]
- a superheavy, synthetic, radioactive element with a very short half-life. Symbol: Db; atomic number: 105.
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Origin of dubnium
named after Dubna, the town in Russia where it was first produced; see -ium
Formerly hahnium, unnilpentium, element 105.
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
dubnium
- a synthetic transactinide element produced in minute quantities by bombarding plutonium with high-energy neon ions. Symbol: Du; atomic no 105See hahnium
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Word Origin
C20: after Dubna, where it was first reported
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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dubnium
[dōōb′nē-əm]
- A synthetic, radioactive element that is produced from californium, americium, or berkelium. Its most long-lived isotopes have mass numbers of 258, 261, 262, and 263 with half-lives of 4.2, 1.8. 34, and 30 seconds, respectively. Atomic number 105. See Periodic Table.
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The American Heritage® Science Dictionary
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