| slovo | definícia |
protactinium
(encz) | protactinium,protaktinium n: Zdeněk Brož |
Protactinium
(gcide) | Protactinium \Protactinium\
The radioactive chemical element, of atomic number 91; Atomic
symbol Pa; at. wt. of longest-lived isotope, 231 (T1/2 =
32,500 yrs.) Also called brevium, Uranium X2 and UX2.
[PJC] |
protactinium
(wn) | protactinium
n 1: a short-lived radioactive metallic element formed from
uranium and disintegrating into actinium and then into lead
[syn: protactinium, protoactinium, Pa, {atomic number
91}] |
protactinium
(elements) | protactinium
Symbol: Pa
Atomic number: 91
Atomic weight: (231)
Radioactive metallic element, belongs to the actinoids. The most stable
isotope, Pa-231 has a half-life of 2.43*10^4 years. At least 10 other
radioactive isotopes are known. No practical applications are known.
Discovered in 1917 by Lise Meitner and Otto Hahn.
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| | podobné slovo | definícia |
Protactinium
(gcide) | Protactinium \Protactinium\
The radioactive chemical element, of atomic number 91; Atomic
symbol Pa; at. wt. of longest-lived isotope, 231 (T1/2 =
32,500 yrs.) Also called brevium, Uranium X2 and UX2.
[PJC] |
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