europium


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Related to europium: europium oxide

europium

(yo͝orō`pēəm) [from Europe], metallic chemical element; symbol Eu; at. no. 63; at. wt. 151.964; m.p. about 820°C;; b.p. about 1,600°C;; sp. gr. 5.25 at 25°C;; valence +2 or +3. Europium is a ductile silvery-white metal; it is both rare and expensive. It is a member of Group 3 of the periodic tableperiodic table,
chart of the elements arranged according to the periodic law discovered by Dmitri I. Mendeleev and revised by Henry G. J. Moseley. In the periodic table the elements are arranged in columns and rows according to increasing atomic number (see the table entitled
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. Its oxides are found in minerals with the other rare earthsrare earths,
in chemistry, oxides of the rare-earth metals. They were once thought to be elements themselves. They are widely distributed in the earth's crust and are fairly abundant, although they were once thought to be very scarce.
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. Europium has been identified in the sun and some stars by spectroscopy. Its physical properties are like those of the other members of the lanthanide serieslanthanide series,
a series of metallic elements, included in the rare-earth metals, in Group 3 of the periodic table. Members of the series are often called lanthanides, although lanthanum (atomic number 57) is not always considered a member of the series.
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, but many of its chemical properties are more like those of calcium. The most reactive of the rare-earth metalsrare-earth metals,
in chemistry, group of metals including those of the lanthanide series and actinide series and usually yttrium, sometimes scandium and thorium, and rarely zirconium. Promethium, which is not found in nature, is not usually considered a rare-earth metal.
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, it tarnishes quickly in air at room temperature and ignites and burns above 150°C;. It reacts readily with water. Twenty-one isotopes of europium are known, most of them unstable. Since it is a good neutron absorber, europium metal is used in nuclear reactor control rods. Europium oxide, a pinkish powder, is used to activate red phosphors in the manufacture of color television picture tubes. The discovery of europium is credited to Eugène Demarcay, who isolated fairly pure europium oxide in 1901.
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europium

[yu̇′rō·pē·əm]
(chemistry)
A member of the rare-earth elements in the cerium subgroup, symbol Eu, atomic number 63, atomic weight 151.96, steel gray and malleable, melting at 1100-1200°C.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

europium

a soft ductile reactive silvery-white element of the lanthanide series of metals: used as the red phosphor in colour television and in lasers. Symbol: Eu; atomic no.: 63; atomic wt.: 151.965; valency: 2 or 3; relative density: 5.244; melting pt.: 822?C; boiling pt.: 1527?C
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
References in periodicals archive ?
Development of functionalized fluorescent europium nanoparticles for bio-labeling and time-resolved fluorometric applications.
An increase in excitation and emission bands intensities was observed with the increase of europium concentration.
The surface complex constants for the europium species sorbed onto the titanium pyrophosphate were obtained from the sorption isotherms as function of pH using the FITEQL program and the CCM.
However, when longer heat treatment times have been applied, quenching of europium transitions was noticed.
A large number of peaks containing both neutral and ionized Europium were observed at 372.4 (II) nm, 381.9 (II) nm, 390.6 (II), 397.1(11) nm, 412.9 (II) nm, 420.4 (II), 443.5 (II) nm, 451.1 (II) nm, 459.3 (I) nm, 462.6 (I) nm, 466.1(1), 551.0 (I) nm, 554.7 (I) nm, 557.0 (I) nm, 557.7 (I) nm, 557.9 (I) nm respectively (Fig.
The comparison of the data on europium concentration and isotopic composition of carbon ([[delta].sup.13]) in sapropelites extracted from the Volzhsky layer rocks of this suite in a number of areas in Western Siberia showed that between the changes of Eu content and [[delta].sup.13] values there exists parallelism, which is not connected with the depth of original organic matter burial but correlated with the catagenesis stages B-GF (pic.1, table 1).
Price increases for Ngualla's second and third highest revenue contributors (Figure 4) of praseodymium and europium have also improved significantly at 50% and 18% respectively.
Doping can prevent concentration quenching of the europium emission that could otherwise be caused by the aggregation of the molecules of the complex.
Akmaeva, "Synthesis and luminescent performances of some europium activated yttrium oxide based systems," Optical Materials, vol.
The researchers have found that by squeezing the porous solid, cavities in the material opened wider, allowing the europium ions in, but not out.
The group of metals commonly referred to as rare earth elements includes 17 little known elements such as lanthanum, cerium, praseodymium, neodymium, europium, dysprosium and gadolinium.
China is the production source of some 97 percent of 1 7 rare earth elements, including: europium, which is used in fiber optics; neodymium and lanthanum, which are essential components for electric cars; and indium, a crucial component of flat-screen TVs and solar energy.