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== गुण ==
युरोपियम [[रेर अर्थ तत्त्व]]य् दक्ले रियाक्टिभ तत्त्व ख। थ्व तत्त्व वातावरणय् छकलं अक्सिडाइज जुइ व थुकिया लनापया रियाक्सन क्याल्सियमया थें न्यागु जुइ। थ्व धातुया ठोस रुपयात मिनरल चिकंनं भुनातःसां थुकिलि शाइन दैमखु। युरोपियम वायुइ १५०-१८०डि॰से॰य् च्याइ। थ्व तत्त्व लिड ति हे कडा जु व सिक्क [[डक्टाइल]] नं जु। युरोपियम छगू धातु ख व थ्व ८०जिपास्कलय् १.८ केल्भिनय् सुपरकन्डक्टर जुइ। <ref>{{cite journal| author = M. Debessai et al. | title = Pressure-Induced Superconducting State of Europium Metal at Low Temperatures| journal = Phys. Rev. lett.| doi = 10.1103/PhysRevLett.102.197002| volume =102| page =197002| year = 2009}}</ref>
== History ==
Europium was first found by [[Paul Émile Lecoq de Boisbaudran]] in 1890, who obtained basic fraction from [[samarium]]-[[gadolinium]] concentrates which had spectral lines not accounted for by [[samarium]] or [[gadolinium]]; however, the discovery of europium is generally credited to [[France|French]] [[chemist]] [[Eugène-Anatole Demarçay]], who suspected samples of the recently discovered element [[samarium]] were contaminated with an unknown element in 1896 and who was able to isolate europium in 1901.
When the europium-doped yttrium orthovanadate red phosphor was discovered in the early 1960s, and understood to be about to cause a revolution in the color television industry, there was a mad scramble for the limited supply of europium on hand among the monazite processors. (Typical europium content in monazite was about 0.05%.) Luckily, Molycorp, with its [[bastnäsite]] deposit at [[Mountain Pass, California]], whose lanthanides had an unusually "rich" europium content of 0.1%, was about to come on-line and provide sufficient europium to sustain the industry. Prior to europium, the color-TV red phosphor was very weak, and the other phosphor colors had to be muted, to maintain color balance. With the brilliant red europium phosphor, it was no longer necessary to mute the other colors, and a much brighter color TV picture was the result. Europium has continued in use in the TV industry ever since, and, of course, also in computer monitors. Californian bastnäsite now faces stiff competition from [[Bayan Obo]], China, with an even "richer" europium content of 0.2%.
Frank Spedding, celebrated for his development of the ion-exchange technology that revolutionized the rare earth industry in the mid-1950s once related the story of how, in the 1930s, he was lecturing on the rare earths when an elderly gentleman approached him with an offer of a gift of several pounds of europium oxide. This was an unheard-of quantity at the time, and Spedding did not take the man seriously. However, a package duly arrived in the mail, containing several pounds of genuine europium oxide. The elderly gentleman had turned out to be Dr. McCoy who had developed a famous method of europium purification involving redox chemistry.
== Occurrence ==
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