TM is an abbreviation for the chemical element thulium Thulium.
In 1879 Cliff isolated the oxides of two new elements. One was named thulium in honor of Thulia, the Scandinavian peninsula where Cliff's homeland is located, and the symbol of the element, which was once Tu, is now used as Tm.
Thulium? Is a silver-white metal, ductile, soft can be cut with a knife; melting point 1545 ° C, boiling point 1947 ° C, density 9.3208. thulium in the air is relatively stable; thulium oxide is a light green crystal. The element thulium has an atomic number of 69 and an atomic weight of 168.93421, and its name comes from the name of the country in which it was discovered.In 1879, the Swedish scientist Clive isolated thulium and holmium from erbium earth.
Extended information:
Thulium uses
1. High-intensity discharge light sources
Thulium is often introduced into high-intensity discharge light sources in the form of high-purity halogens (usually thulium bromide). Thulium is often introduced as a high-purity halide (usually thulium bromide) into high-intensity discharge light sources in order to utilize the spectrum of thulium.
2. Lasers
Holmium-chromium-thulium-triple doped yttrium aluminum garnet (Ho:Cr:Tm:YAG) is a highly efficient active laser medium. It can emit laser light at a wavelength of 2097 nm and is widely used in military, medical and meteorological applications. Thulium-mono-doped yttrium aluminum garnet can emit laser light at wavelengths between 1930 nm and 2040 nm, which is very effective for ablation on tissue surfaces.
3. X-ray sources
Despite their high cost, thulium-containing portable X-ray equipment is beginning to be used in large quantities as radiation sources in nuclear reactions. These sources have a useful life of about one year and can be used as tools for medical and dental diagnostics, as well as for defect detection in mechanical and electronic components that are difficult to reach by human labor. These sources do not require a lot of radiation protection - only a small amount of lead is needed.
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