| slovo | definícia |
hafnium
(encz) | hafnium,hafnium n: [chem.] macska |
hafnium
(czen) | hafnium,hafniumn: [chem.] macska |
hafnium
(gcide) | hafnium \haf"ni*um\ (h[a^]f"n[=e]*[u^]m or h[aum]f"n[=e]*[u^]m),
n.
A metallic element of atomic number 72 present together with
zirconium to the extent of 1% to 5% in zirconium minerals. It
is a poisonous, ductile metal with a brilliant silver luster,
has an atomic weight of 178.49, and has a high melting point
(2227[deg] C). It is used in nuclear reactors, and
incandescent lamps as a scavenger of oxygen and nitrogen. See
also norium.
[1913 Webster] |
hafnium
(wn) | hafnium
n 1: a grey tetravalent metallic element that resembles
zirconium chemically and is found in zirconium minerals;
used in filaments for its ready emission of electrons [syn:
hafnium, Hf, atomic number 72] |
hafnium
(elements) | hafnium
Symbol: Hf
Atomic number: 72
Atomic weight: 178.49
Silvery lustrous metallic transition element. Used in tungsten alloys in
filaments and electrodes, also acts as a neutron absorber. First
reported
by Urbain in 1911, existence was finally established in 1923 by D.
Coster,
G.C. de Hevesy in 1923.
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