-10-
in the HC} and H,SO0, fractions.
zr95_Np? was not eluted with any
of the agents used, and it, along with traces of Sbi25 was found in
the resin at the end of the experiment.
The oxalic acid fraction, which
according to the method of Smith and Reynolds 18 should contain Sb 125,
was analyzed in a gamma spectrometer for the presence of Sb!
25
Figure 3a shows the gamma spectrum for the fraction and demonstrates
the presence of strong peaks at energies of 0.17 Mev, 0.43 Mev,
0.61 Mev.
and
The peaks are in agreement with those of Sb125 ag given by
Lazar be both as to energy and relative intensity.
Confirmation of the presence of Sb !25 in a portion of the anion
fraction was obtained by the use of standard radiochemical precipitation
procedures.
The gamma spectrum of the resulting Sb9S, precipitate
from the procedure is given in Figure 3b.
The relative intensity and
energy of the peaks corresponded to those obtained with
the
0.1M
oxalic acid fraction from the anion-exchange separation.
Oxalic Acid Fraction from the Dowex 50 Separation
When a one-milliliter aliquot of the oxalic acid fraction from
the
Dowex 50 separation was plated, flamed, and counted in a methane gas-
flow chamber with and without a 4.7 mg/cm? aluminum absorber,
count in the: sample was reduced from 314 c/m to 41 c/m.
This
the
re-
duction in count indicated that the major portion of the radioactivity was
of low energy and suggested the presence of Fe55 contaminated with