Re: specific activity

[Dave Derenzo <dave@uic.edu>]

OOPS! Thanks to the eagle eye of Chris A. Marthaller, I must admit a 
significant error in the conversion in the second example.  The correct 
conversion for S-35 is:

S.A. = (226 x 1600)/(35 x 87.51 d /365.25 d/y) = 4.31E4 Ci/g = 4.31E10 uCi/g

That's what I get for trying to do this so early in the morning.

At 08:19 AM 06/15/2000 -0500, you wrote:
>See Herman Cember's book, third edition, Equation 4.31 on p.95.
>
>S.A. = (226 x 1600)/(Atomic Weight x Half Life in Years)
>
>226 and 1600 refer to the atomic weight and half-life in years of
>radium-226.  Simply plug the atomic weight and half-life (in years) of the
>radionuclide of interest into the equation.  This will yield the specific
>activity in Ci/g.
>
>He provides examples for C-14 and S-35:
>
>C-14
>S.A. = (226 x 1600)/(14 x 5730) = 4.5 Ci/g
>(The book gives 4.6 as the answer, but the above answer is correct)
>
>S-35 (I modified this example slightly)
>S.A. = (226 x 1600)/(35 x 87.51 d /365.25 d/y) = 4.31E4 Ci/g = 0.04 uCi/g
>
>If you are interested in specific concentration, divide the activity by the
>volume of the solution.
>
>Dave Derenzo
>
>At 12:49 PM 06/14/2000 -0500, you wrote:
> >how does one go about determining the specific activity of something in
> >uCi/g ?
> >________________________________________________________________________
> >Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com
> >
> >************************************************************************
> >The RADSAFE Frequently Asked Questions list, archives and subscription
> >information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html
>
>
>Dave Derenzo, RSO (dave@uic.edu)
>UIC Radiation Safety Section, M/C 932
>Phones: Voice (312) 996-1177  Fax: (312) 996-8776
>
>************************************************************************
>The RADSAFE Frequently Asked Questions list, archives and subscription
>information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html


Dave Derenzo, RSO (dave@uic.edu)
UIC Radiation Safety Section, M/C 932
Phones: Voice (312) 996-1177  Fax: (312) 996-8776

************************************************************************
The RADSAFE Frequently Asked Questions list, archives and subscription
information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html