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samarium
sa·mar·i·um S0053200 (sə-mâr′ē-əm, -măr′-)n. Symbol Sm A silvery or pale gray metallic element of the lanthanide series found in the minerals monazite and bastnaesite and used as a dopant for laser materials, in infrared absorbing glass, and as a neutron absorber in certain nuclear reactors. Atomic number 62; atomic weight 150.36; melting point 1,072°C; boiling point 1,794°C; specific gravity (approximately) 7.520 (25°C); valence 2, 3. See Periodic Table. [samar(skite), the mineral from which samarium was first isolated in 1879 + -ium.]samarium (səˈmɛərɪəm) n (Elements & Compounds) a silvery metallic element of the lanthanide series occurring chiefly in monazite and bastnaesite and used in carbon-arc lighting, as a doping agent in laser crystals, and as a neutron-absorber. Symbol: Sm; atomic no: 62; atomic wt: 150.36; valency: 2 or 3; relative density: 7.520; melting pt: 1074°C; boiling pt: 1794°C[C19: New Latin, from samarskite + -ium]sa•mar•i•um (səˈmɛər i əm) n. a rare-earth metallic element discovered in samarskite. Symbol: Sm; at. wt.: 150.35; at. no.: 62; sp. gr.: 7.49. [1875–80; < New Latin; see samarskite, -ium2] sa·mar·i·um (sə-mâr′ē-əm) Symbol Sm A silvery-white metallic element of the lanthanide series that exists in several forms and has seven naturally occurring isotopes. It is used to make glass that absorbs infrared light and to absorb neutrons in nuclear reactors. Atomic number 62. See Periodic Table.ThesaurusNoun | 1. | samarium - a grey lustrous metallic element of the rare earth group; is used in special alloys; occurs in monazite and bastnasiteatomic number 62, Smmetal, metallic element - any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc.bastnaesite, bastnasite - a yellow-to-brown mineral that is a source of rare earth elementsmonazite - a reddish-brown mineral containing rare earth metals; an important source of thorium and cerium | Translationssamarium
samarium (səmâr`ēəm), metallic chemical element; symbol Sm; at. no. 62; at. wt. 150.36; m.p. 1,072°C;; b.p. 1,791°C;; sp. gr. 7.54 at 20°C;; valence +2 or +3. Samarium is a lustrous silver-white metal. It is one 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. ..... Click the link for more information. 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. ..... Click the link for more information. in 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 ..... Click the link for more information. . It has two crystalline forms (see allotropyallotropy [Gr.,=other form]. A chemical element is said to exhibit allotropy when it occurs in two or more forms in the same physical state; the forms are called allotropes. ..... Click the link for more information. ). The metal does not oxidize at room temperature but ignites when heated above 150°C;. Samarium is found widely distributed in nature; it is obtained commercially from the minerals monazitemonazite , yellow to reddish-brown natural phosphate of the rare earths, mainly the cerium and lanthanum metals, usually with some thorium. Yttrium, calcium, iron, and silica are frequently present. ..... Click the link for more information. and bastnasite. Naturally occurring samarium is a mixture of seven isotopes, three of which are radioactive with extremely long half-lives. The metal was not isolated in relatively pure form until recently, although it has long been used in pyrophoric alloys used in cigarette lighter flints. Samarium is used as a catalyst in certain organic reactions. A samarium-cobalt compound, SmCo5, is used to make magnets for use in computer memories. The oxide, samaria, is used in special infrared absorbing glass and cores of carbon arc-lamp electrodes. Since one isotope of samarium is a good neutron absorber, the element has found use in nuclear reactor control rods. Samarium was discovered in 1879 by P. E. Lecoq de Boisbaudran by spectroscopic analysis of the mineral samarskite.samarium[sə′mar·ē·əm] (chemistry) A rare-earth metal, atomic number 62, symbol Sm; melts at 1350°C, tarnishes in air, ignites at 200-400°C. samarium a silvery metallic element of the lanthanide series occurring chiefly in monazite and bastnaesite and used in carbon-arc lighting, as a doping agent in laser crystals, and as a neutron-absorber. Symbol: Sm; atomic no.: 62; atomic wt.: 150.36; valency: 2 or 3; relative density: 7.520; melting pt.: 1074°C; boiling pt.: 1794°C samarium
samarium [sah-ma´re-um] a chemical element, atomic number 62, atomic weight 150.35, symbol Sm. (See Appendix 6.) The complex samarium Sm 153 lexidronam is used in the palliative treatment of bone pain associated with osteoblastic metastatic bone lesions, administered intravenously.sa·mar·i·um (Sm), (să-mār'ē-ŭm), A metallic element of the lanthanide group, atomic no. 62, atomic wt. 150.36. [bands indicating its presence were first found in the spectrum of samarskite, a mineral named after V. E. Samarski-Bykhovets, a 19th-century Russian mining engineer] sa·mar·i·um (să-mar'ē-ŭm) A metallic element of the lanthanide group, atomic no. 62, atomic wt. 150.36. [bands indicating its presence were first found in the spectrum of samarskite, a mineral named after V. E. Samarski-Bykhovets, a 19th-century Russian mining engineer]FinancialSeeSMSee SM See SMsamarium Related to samarium: europium, samarium oxideSynonyms for samariumnoun a grey lustrous metallic element of the rare earth groupSynonymsRelated Words- metal
- metallic element
- bastnaesite
- bastnasite
- monazite
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