/dis proh"see euhm, -shee-/, n. Chem.
a rare-earth metallic element, highly reactive and paramagnetic, found in small amounts in various rare-earth minerals, as euxenite and monazite: used to absorb neutrons in nuclear reactors. Symbol: Dy; at. wt.: 162.50; at. no.: 66.
[1885-90; < NL < Gk dysprós(itos) hard to get at (dys- DYS- + pros- to + itós, ptp. of iénai to go) + -IUM]

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 (Dy), chemical element, rare-earth metal of the lanthanoid series of the periodic table. A relatively hard and very reactive metal, it is oxidized by air and by water. Its high melting point and ability to absorb neutrons make it useful in control rods for nuclear reactors. Its compounds have been used for making laser materials, as components in some electronic equipment, and as phosphor activators.

      P.-É. Lecoq de Boisbaudran (Lecoq de Boisbaudran, Paul-Émile) first found this element (1886) associated with holmium and other heavy rare earths; Georges Urbain later (1906) was able to prepare a reasonably pure fraction. Some important mineral sources of dysprosium are xenotime, fergusonite, gadolinite, euxenite, polycrase, and blomstrandine. It occurs also in the products of nuclear fission. Commercial separation is performed by ion-exchange methods. The metal has been prepared by thermoreduction of the anhydrous halides with alkali or alkaline-earth metals. Dysprosium metal at room temperature is crystallized in a hexagonal close-packed structure, below -168° C is ferromagnetic, and at very low temperatures is superconductive. The naturally occurring isotopes are all stable and have mass numbers 156, 158, 160, 161, 162, 163, and 164; the last four make up nearly 98 percent of natural dysprosium.

      Chemically, dysprosium behaves as a typical trivalent rare earth and forms a series of pale yellow compounds in which its oxidation state is +3. The Dy3+ ion is strongly paramagnetic; this property has been harnessed to produce magnetic cooling to very low temperatures.

atomic number
atomic weight
melting point
1,412° C
boiling point
2,567° C
8.551 (25° C)
oxidation state
electronic config.
[Xe]4f 105d06s2

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Universalium. 2010.

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  • Dysprosium — (pronEng|dɪsˈproʊziəm) is a chemical element with the symbol Dy and atomic number 66. Characteristics Dysprosium is a rare earth element that has a metallic, bright silver luster, relatively stable in air at room temperature, but dissolving… …   Wikipedia

  • Dysprosium — Terbium ← Dysprosium → Holmium …   Wikipédia en Français

  • dysprosium — [ disprozjɔm ] n. m. • 1886; gr. dusprositos « difficile à atteindre » ♦ Chim. Élément atomique (Dy; no at. 66; m. at. 162,5), métal du groupe des terres rares d éclat métallique analogue à celui de l argent. ● dysprosium nom masculin (grec… …   Encyclopédie Universelle

  • dysprosium — Symbol: Dy Atomic number: 66 Atomic weight: 162.50 Metallic with a bright silvery white lustre. Dysprosium belongs to the lanthanoids. It is relatively stable in air at room temperatures, it will however dissolve in mineral acids, evolving… …   Elements of periodic system

  • Dysprosium — Dys*pro si*um, n. [NL., fr. Gr. dyspro sitos hard to get at.] (Chem.) An element of the rare earth group. Symbol Dy; at. wt., 162.5. [Webster 1913 Suppl.] …   The Collaborative International Dictionary of English

  • dysprosium — element, obtained 1906 from an earth discovered in 1886, the last to be extracted from the complex earth called yttria, and named dysprosia in reference to the difficulty of obtaining it, from Gk. dysprositos hard to get at, difficult of access,… …   Etymology dictionary

  • dysprosium — [dis prō′zē əm, dis prō′sēəm] n. [ModL < Gr dysprositos, difficult of access < dys , DYS + prositos, approachable < prosienai, come to < pros, toward + ienai, to go (see ION): so named (1886) by its discoverer, Fr chemist P. E. Lecoq… …   English World dictionary

  • Dysprosium — Eigenschaften …   Deutsch Wikipedia

  • Dysprosium — Dys|pro|si|um 〈n.; s; unz.; chem. 〉 chem. Element, Metall der seltenen Erden [zu grch. dysprositos „schwer zu erlangen“] * * * Dys|pro|si|um [griech. dysprósitos = schwer zugänglich; ↑ ium (1)], das; s; Symbol: Dy; chem. Element, Protonenzahl 66 …   Universal-Lexikon

  • Dysprosium — disprozis statusas T sritis fizika atitikmenys: angl. dysprosium vok. Dysprosium, n rus. диспрозий, m pranc. dysprosium, m …   Fizikos terminų žodynas

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