- published: 19 Jan 2009
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Ytterbium ( /ɨˈtɜrbiəm/ i-TUR-bee-əm) is a chemical element with the symbol Yb and atomic number 70. It is the fourteenth and penultimate element in the lanthanide series, or last element in the f-block, which is the basis of the relative stability of the +2 oxidation state. However, like the other lanthanides, the most common oxidation state is +3, seen in its oxide, halides and other compounds. In an aqueous solution, like compounds of other late lanthanides, soluble lutetium compounds form a complex with nine water molecules.
In 1878, the Swiss chemist Jean Charles Galissard de Marignac separated in the rare earth of "erbia" another independent component, which he called "ytterbia", for Ytterby, the Swedish village near where he found the new component of erbium. He suspected that ytterbia was a compound of a new element that he called "ytterbium" (note that in total four elements were named after the place, other being yttrium, terbium and erbium). In 1907, the new earth "lutecia" was separated from ytterbia, from which the element "lutecium" (now lutetium) was extracted. A relatively pure sample of the metal was obtained only in 1953. In present, ytterbium is mainly used as a dopant of stainless steel, active media, and usage as a gamma ray source also occurred.
Kurt Donald Cobain (February 20, 1967 – April 5, 1994) was an American singer-songwriter, musician and artist, best known as the lead singer and guitarist of the grunge band Nirvana. Cobain formed Nirvana with Krist Novoselic in Aberdeen, Washington in 1985 and established it as part of the Seattle music scene, having its debut album Bleach released on the independent record label Sub Pop in 1989.
After signing with major label DGC Records, the band found breakthrough success with "Smells Like Teen Spirit" from its second album Nevermind (1991). Following the success of Nevermind, Nirvana was labeled "the flagship band" of Generation X, and Cobain hailed as "the spokesman of a generation". Cobain, however, was often uncomfortable and frustrated, believing his message and artistic vision to have been misinterpreted by the public, with his personal issues often subject to media attention. He challenged Nirvana's audience with its final studio album In Utero (1993).
During the last years of his life, Cobain struggled with heroin addiction, illness and depression. He also had difficulty coping with his fame and public image, and the professional and lifelong personal pressures surrounding himself and his wife, musician Courtney Love. On April 8, 1994, Cobain was found dead at his home in Seattle, the victim of what was officially ruled a suicide by a self-inflicted shotgun wound to the head. The circumstances of his death at age 27 have become a topic of public fascination and debate. Since their debut, Nirvana, with Cobain as a songwriter, has sold over 25 million albums in the U.S. alone, and over 50 million worldwide.