resulting in a density of 1.0.
Small samples,
spiny lobster
hepatopancreas for example, were ashed, dissolved in hydrochloric acid,
and sealed in PVC pipe.
Oven-dried soil samples were compressed to a densit of
1.35 in PVC pipe.
Spectrum resolution was done by Schonfeld's
of least squares.
(1965)
method
A set of previously prepared reference spectra
for the different geometries and radionuclides was used.
All
values were corrected for decay to the date of collection.
The
- error given for individual values is the 95% error.
Strontium-90 Analyses
Strontium-90 was determined by measuring the equilibrium
concentration of its 90 daughter.
Yttrium-90 was separated by
solvent extraction and precipitation techniques
(Petrow,
1965),
with stdble yttrium serving as both a carrier and a yield determinant.
Recoveries ranged from 80 to 100%.
Iron-55 Analyses
Iron-55 was separated and purified by a combination of
solvent extraction and electrodeposition techniques (Palmer and
Beasley,
1967).
Recoveries generally exceeded 90%.
Counting
was done by X-ray spectroscopy with a proportional counter in
conjunction with a multichannel analyzer.