the sample as
‘e, 5 mg of La,
dto 2 liters
}
b,. There are considerable differences between the
Sr radioactivity above and below the thermocline which
A nas to increase from South to north
eparated from
|
_in hydrochloric
¢. The vertical distribution of LiAce differs from
“that of 20Sr and there is no difference between the
radioactivity above and below the thermocline in the
d separated
e was ignited
South Equatorial Current region. However, in the North
Equatorial Current region, radioactivity of Lhkce
decreases abrupply from the surface to the thermocline.
ted toa 9M
drivalent by
After the MIBK
The value of l44Ce at Station 39, at the 150 m level is
ion containing
pped by water
de, precipitated
BH 3=abnormally large, but the values of 20Sr and 137Cs at same
location are normal. This may be, perhaps, due to the
!
effect of biological concentration.
r then counted
5. Relation between radioactivity and dissolved oxygen.
oletely decayed
Fig. 7 shows that the relation between Osr
radioactivity and dissolved oxygen is exhibited as
|
scame negligible.
@
linear function. This seems to indicate that 90Sr
> the same
{
‘to a deeper layer by the mixing
in the same manner as dissolved
coincides with the chemical and
of 20Sr in sea water due to the
amounts of the stable isotopg.
1s determined
“able Le
supplied to the marine surface as fallout is transported
;
action of sea water
oxygen. This result
biological stability
existence of large
On the other hand,
> Shown in Fig 1.
‘oups, that is,
- there is no linear relationship between 1l44Ce radio_ activity and dissolved oxygen values. We think this
to the Equatorial
4 Sea water.
ie South
> is due to the unstability of the M4Ce nuclide in
id 43 to the
‘ater temperature.
ture range of
hese temperature
aL
66. tke to 90sr
f@
S in Fig. 6.
§ differences
Cs and l44ce
rth Equatorial
nce between
|
'
In the South Equatorial Current, the values of
Whe/P0sr above the thermocline are smaller than
} those of below the thermocline. These results seem
' to indicate that M4Ce absorbs to a particular materials
|
|
and suffers the effect of mixing and gravity during
its motion in sea water, allowing MACe to reach a
deeper layer faster than 90Sr.