A. ITT.
101
O. Paaxkxona, R. NASANEN, D. MERTEN and J. K. Mrerrinen, Strontium 90
Analyses of the grass samples
Atomizer).
ries of the
thod on a
rer Bunsen
e in quartz
‘orrespondlorgan and
re made as
immonium
sarated by
osferred to
um carrier
9
Grass samples from the farms (Nos. 1—9) representing the plots on
which the cattle had been kept during the last 2—3 weeks, were dried on
the farms in a dust-free place and ca. 10 kg of airdry grass was sent in a
paper bag to the laboratory where it was burnt to ash in the same way as
the milk samples. 10 g of ash was used for each analysis.
The chemical separation of Sr was made by the method of Bryant et al.
(14) with the same exceptions as in the milk analyses (see above). However,
the grass ash was dissolved in a mixture of perchloric and nitric acids by
the method of Bryant, Chamberlain, Morgan and Spicer (15). The yield of
strontium andthe radioactivity of the yttrium precipitates were determined
as for the milk samples. Caletum was determined permanganometrically, as
for a part of the milk powder samples. For dry weight determinations the
grass was kept at 105—110°C for 20 hours.
days.
d from the
ammonia.
‘lask for a
s dissolved
was added
The results
The results of the milk analyses are represented in Table 2, those of the
grass analyses in Table 3.
serformed.
Table 2
ie remain) The cenation was
Results of calcium and “Sr analyses of the milk samples of Table 1.
elss) using
strontium
ed with a
d of 1.2—
ples grav© samples
vith 0.1 N
rit for 24
les varied
Sample
No.
Ca
% of ash
Sr,
Sr, upuc/kg of
Hucig of ash
dry weight
Sr,
fuc/g Ca
I
16.6
0.61
35.2
3.7
2
15.5
1.00
55.4
6.7
3
4
5
6
7
17.5
16.2
14.3
16.0
16.8
0.79
0.67
0.52
0.78
1.12
45.0
35.3
30.0
43.7
61.6
4.5
4.2
3.6
4.9
6.6
8
16.6
0.98
53.0
5.9
9
17.3
2.01
96.5
11.6
10
11
12
13
14
15
16.5
16.8
16.4
17.4
17.1
16.5
1.61
1.63
1.31
1.47
1.36
1.41
118
125
96.3
118
106
109
9.8
9.7
8.0
8.4
7.9
8.6