thulium
- Domaine
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- chimiechimie minérale
- Date
Termes :
- thulium n. m.
- Tm
Traductions
-
anglais
Date :Définition
An element. State: Solid; Group: IIIB (Lanthanide Series); Atomic No.: 69; Atomic Wt. 168.9342; Valence: 3; Isotopes: None stable 2 radioactive. Thulium, m.p. 1545 °C (2813 °F), is a minor element of the rare-earth group, occurring in association with yttrium in a number of ores such as xenotime and euxenite found in monazite sands. It is stable in air and reacts slowly with halogen elements at room temperature; it also forms compounds with oxygen, carbon, nitrogen, and hydrogen at high temperatures.
Notes :
It has few important uses; small pellets can be used as a portable source of diagnostic x-rays, and there is also as possibility of application in magnetic ceramic materials (ferrites).
Named for thule, a legendary name for the most northerly part of the habitable world.Termes :
- thulium
- Tm
[Tm] Symbol for the element thulium, named for Thule, a legendary name for the most northerly part of the habitable world.