Dubnium is an artificially produced chemical element with symbol Db and atomic number 105. It is highly radioactive: the most stable known isotope, dubnium-268, has a half-life of just over a day. Credit for discovery of the element was contested between the Soviet Joint Institute for Nuclear Research and American Lawrence Berkeley Laboratory beginning in 1970; the dispute was resolved in 1993 by an official investigation of the IUPAC/IUPAP Joint Working Party, which awarded joint credit. The element was officially named in 1997 after the town of Dubna, the site of the Soviet institute. Dubnium should share most of its chemical properties, such as its valence electron configuration and a dominant +5 oxidation state, with other group 5 elements, such as vanadium, niobium, and tantalum, with a few anomalies due to relativistic effects. Solution chemistry experiments have revealed that dubnium often behaves more like niobium than tantalum, breaking periodic trends.
Read more: <https://en.wikipedia.org/wiki/Dubnium> _______________________________ Today's selected anniversaries: 1658: Pope Alexander VII appointed François de Laval as vicar apostolic of New France. <https://en.wikipedia.org/wiki/Fran%C3%A7ois_de_Laval> 1892: Liverpool F.C., one of England's most successful football clubs, was founded. <https://en.wikipedia.org/wiki/Liverpool_F.C.> 1943: Off-duty U.S. sailors fought with Mexican American youths in Los Angeles, spawning the Zoot Suit Riots. <https://en.wikipedia.org/wiki/Zoot_Suit_Riots> 1968: American artist Andy Warhol and two others were shot and wounded at his New York City studio "The Factory" by radical feminist Valerie Solanas. <https://en.wikipedia.org/wiki/Andy_Warhol> 2012: Dana Air Flight 992, a passenger flight from Abuja to Lagos, Nigeria, suffered dual engine failure and crashed into a building, resulting in the deaths of all 153 on board and 10 more on the ground. <https://en.wikipedia.org/wiki/Dana_Air_Flight_992> _____________________________ Wiktionary's word of the day: spoof: 1. (transitive) To deceive. 2. (transitive, computing) To falsify. <https://en.wiktionary.org/wiki/spoof> ___________________________ Wikiquote quote of the day: The truth is, that most men want knowledge, not for itself, but for the superiority which knowledge confers; and the means they employ to secure this superiority, are as wrong as the ultimate object, for no man can ever end with being superior, who will not begin with being inferior. --Sydney Smith <https://en.wikiquote.org/wiki/Sydney_Smith> _______________________________________________ Wikipedia Daily Article mailing list. To unsubscribe, visit: https://lists.wikimedia.org/mailman/listinfo/daily-article-l Questions or comments? Contact [email protected]
