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单词 technetium
释义 technetium|tɛkˈniːʃ(ɪ)əm|
[mod.L., f. Gr. τεχνητ-ός artificial (f. τεχνᾶσθαι to make by art, f. τέχνη art, craft) + -ium.]
A dense, refractory, radioactive metallic element, chemically similar to rhenium, which occurs naturally only in trace amounts but is produced in reactors as a fission product of uranium and by neutron irradiation of molybdenum 98 and is used medically as a tracer in scintigraphy. Symbol Tc; atomic number 43. Formerly called masurium.
1947Perrier & Segrè in Nature 4 Jan. 24/1 We would like to propose the name of ‘technetium’, from the Greek τεχνητός, artificial, in recognition of the fact that technetium is the first artificially made element. The corresponding chemical symbol should be ‘Tc’.1960J. Kleinberg et al. Inorg. Chem. xxi. 535 The existence of the heptasulfides of technetium and rhenium and their mode of preparation emphasize the high degree of stability of these elements in the + 7 state.1962[see masurium].1969New Scientist 13 Mar. 564/1 Astrophysicists are puzzled to explain how the element technetium, which must be produced in the hot cores of stars, reaches the surface.1974Encycl. Brit. Micropædia IX. 859/2 Technetium metal looks like platinum but is usually obtained as a gray powder.1977Lancet 7 May 1012/1 Individual limbs were scanned 5–6 hr after administration of 10 mCi technetium-99m diphosphonate.
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