Radioactivity, natural
 scroll 
Naturally occurring nuclides which are radioactive.
A distinction is drawn between natural radionuclides which are continuously
regenerated by nuclear reactions of cosmic radiation, cosmogenic radionuclides
(see 'radionuclides, cosmogenic')
and primordial (initial) radionuclides (see 'radionuclides,
primordial'), which have existed since the earth was formed and
due to their long half-life have not yet decayed and the radionuclides
generated from the primordial radionuclides U-238, U-235 and Th-232
of the associated decay chain.
Nuclide |
Aktivity in Bq |
H-3 |
25 |
Be-7 |
25
|
C-14 |
3,800 |
K-40 |
4,200 |
Rb-87 |
650 |
U-238, Th-234, Pa-234m, U-234 |
4 |
Th-230 |
0.4 |
Ra-226 |
1 |
short-lived Rn-222 decay products |
15 |
Pb-210, Bi-210, Po-210 |
60 |
Th-232 |
0.1 |
Ra-228, Ac-228, Th-228, Ra-224 |
1.5 |
short-lived Rn-220 decay products |
30 |
Natural radioactive substances in the
human body
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ENS conferences |
TopFuel 2012
2 - 6 Sept. 2012 in Manchester, UK
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ENC 2012
9 - 12 Dec. 2012 in Manchester, UK |
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