Naturally occurring nuclides which are radioactive. A distinction is drawn between natural radionuclides which are continuously regenerated by nuclear reactions of cosmic radiationRadiation originating directly or indirectly from extraterre..., 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-lifeThe period during which half of the nuclei decay in a quanti... have not yet decayed and the radionuclides generated from the primordial radionuclides U-238, U-235 and Th-232 of the associated decayThe spontaneous conversion of a nuclide into another nuclide... chain.
| NuclideA nuclide is a type of atom characterized by its proton numb... |
Aktivity in BqSymbol for becquerel, the name of the unit for activity. |
|
H-3 |
25 |
|
Be-7 |
25 |
|
C-14See 'Carbon-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 decayThe spontaneous conversion of a nuclide into another nuclide... 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 decayThe spontaneous conversion of a nuclide into another nuclide... products |
30 |
Natural radioactive substancesRadioactive substances within the meaning of the Atomic Ener... in the human body