| 释义 |
scandium Chem.|ˈskændɪəm|
[f. Scandia: see Scandian and -ium; scandium first formed in Sw. (L. F. Nilson 1879, in Öfversigt af K. Vetenskaps-Akad. Förh. XXXVI. iii. 47).]
A silvery white metallic element, the ‘eka-boron’ of Mendeleev, which is found in small quantities in association with rare-earth metals (among which it is often classified) and in some tin and tungsten ores, and forms colourless salts in which it is trivalent. Symbol Sc; atomic number 21. Hence ˈscandia, the white oxide, Sc2O3.
1879Academy 13 Sept. 198 P. T. Cleve has isolated the metal scandium. 1880Jrnl. Chem. Soc. XXXVIII. 7 Scandium forms but one oxide, scandia, Sc2O3. 1887Athenæum 3 Sept. 299/3 Three recognized gaps have been filled by the discovery of the elements gallium, scandium, and germanium. 1905Ibid. 22 July 118/2 Sir Norman Lockyer has also observed in the chromosphere of the sun the spectrum of the rare element scandium, the predicted discovery of which was one of the crowning triumphs of Mendeléeff's Periodic Law. 1922Nature 17 June 799/1 The extraction and purification of scandium from thorveitite of Madagascar. This mineral, which contains 42 per cent of scandium oxide, is fused with soda and the silica removed by washing. 1955Sci. News Let. 11 June 374/3 Studies made by Britain's Hydraulics Research Station and the Atomic Energy Research Establishment have shown that very finely ground glass containing radioactive scandium oxide moves with the mud when mixed with it in the River Thames. 1974Encycl. Brit. Micropædia VIII. 944/3 Nilson discovered..its oxide, scandia, in the rare-earth minerals gadolinite and euxenite. Ibid., Scandium is now produced on a small scale mostly as a by-product of uranium extraction from the mineral davidite (about 0·02 percent scandium oxide). Very few uses..have been developed. |