Difference between revisions of "Gamma Spectroscopy (NORM and TENORM)"
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+ | Written and developed by [http://www.mn.uio.no/kjemi/personer/vit/torbjor/index.html Prof. Tor Bjørnstad] (IFE/UiO) | ||
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+ | back to [[Naturally Occuring Radioactivity - NORM and TENORM]] | ||
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N = number of nuclides<br> D = disintegration rate (Bq, Ci, dimension s-1)<br> A = activity is disintegration rate D per unit of volume or unit of mass (dimension s-1)<br> We distinguish between two notions:<br> As(i) = specific activity is activity per unit of mass of that particular element the actual<br> radionuclide i belongs to. This notion is also used to express the activity of a<br> particular radiolabelled molecule in relation to the total mass of the same molecule<br> (labelled and unlabelled) in the sample (for instance when the inactive molecule is present<br> as a carrier).<br> Ac(i) = activity concentration is the activity of a special radionuclide ''i'' or all present<br> radionuclides (AcT = A<sub>c</sub>(∑i) = total activity) per unit of volume or unit of weight of a radioactive<br> sample.<br> | N = number of nuclides<br> D = disintegration rate (Bq, Ci, dimension s-1)<br> A = activity is disintegration rate D per unit of volume or unit of mass (dimension s-1)<br> We distinguish between two notions:<br> As(i) = specific activity is activity per unit of mass of that particular element the actual<br> radionuclide i belongs to. This notion is also used to express the activity of a<br> particular radiolabelled molecule in relation to the total mass of the same molecule<br> (labelled and unlabelled) in the sample (for instance when the inactive molecule is present<br> as a carrier).<br> Ac(i) = activity concentration is the activity of a special radionuclide ''i'' or all present<br> radionuclides (AcT = A<sub>c</sub>(∑i) = total activity) per unit of volume or unit of weight of a radioactive<br> sample.<br> | ||
Revision as of 16:23, 20 June 2012
Written and developed by Prof. Tor Bjørnstad (IFE/UiO)
back to Naturally Occuring Radioactivity - NORM and TENORM
N = number of nuclides
D = disintegration rate (Bq, Ci, dimension s-1)
A = activity is disintegration rate D per unit of volume or unit of mass (dimension s-1)
We distinguish between two notions:
As(i) = specific activity is activity per unit of mass of that particular element the actual
radionuclide i belongs to. This notion is also used to express the activity of a
particular radiolabelled molecule in relation to the total mass of the same molecule
(labelled and unlabelled) in the sample (for instance when the inactive molecule is present
as a carrier).
Ac(i) = activity concentration is the activity of a special radionuclide i or all present
radionuclides (AcT = Ac(∑i) = total activity) per unit of volume or unit of weight of a radioactive
sample.
N,D and A may, in addition, have an index t (i.e. Nt, Dt and At). This denotes the parameter values at time t relative to a starting time t = 0.
R = counting rate (cps, cpm or generally cpt where t should be defined, dimention s-1)
S = number of counts
N, D, A, R and S may, in addition, have indexes B = background, T = total or N = net. The relations between them are: RN = RT - RB and SN = ST - SB. Other indexes may also be used, for instance SCr-51 in order to separate from SFe-59.