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neodymium

(Encyclopedia)neodymium nēˌōdĭmˈēəm [key], metallic chemical element; symbol Nd; at. no. 60; at. wt. 144.242; m.p. about 1,021℃; b.p. about 3,068℃; sp. gr. 7.004 at 20℃; valence +3. Neodymium is a lust...

Nd

(Encyclopedia)Nd, symbol for the element neodymium. ...

Welsbach, Carl Auer, Baron von

(Encyclopedia)Welsbach, Carl Auer, Baron von kärl ouˈər bärōnˈ fən vĕlsˈbäkh [key], 1858–1929, Austrian chemist. He discovered the rare earth elements neodymium and praseodymium (1885) and lutetium (c.1...

promethium

(Encyclopedia)promethium prōmēˈthēəm [key], artificially produced radioactive chemical element; symbol Pm; at. no. 61; mass no. of most stable isotope 145; m.p. 1,042℃; b.p. 3,000℃ (estimated); sp. gr. unk...

lanthanide series

(Encyclopedia)lanthanide 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 nu...

dating

(Encyclopedia)dating, the determination of the age of an object, of a natural phenomenon, or of a series of events. There are two basic types of dating methods, relative and absolute. In relative dating, the tempor...

Elements (table)

(Encyclopedia)Elements 1 Parentheses indicate most stable isotope; brackets enclose lower and upper bounds of weight variation. ...

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