conc.

Description

Step

neutrons were
to

come

Lrom

Comments

supposed
ail

forgetfulness)

direc-

tions

Etching

20 minutes etching at
5.94N KOH + 0.495 at

60.5%,

40 minutes etching at
5.72N KOU + Q.305 at

The foils were

totally immersed in

3.5 | KOU after CM reading on the
foils were

less

than

1

mR/hr

60.3°C,

SO minutes etching at

5.14N + 0.428 at 60.3°C

Rinse

15-20 minutes

in circu-

latiny distilled water
Drying

86°C oven till dry

Tracks viewing

ad
tracks from 20 min.
etching are needle Like,
for 40 and 80 min. are
smali and big oval-shaped

length and width of the track

a)

and the track density have not
been measured

holes respectively

b)
tracks that have to be
U or Pu Fission tracks
abound on foils in direct
contact with the Al foil
und on the edges of the
foil.
c)
Tmages of the tooth
and the embedding material
is present

d)

Star agpregates are

present though sparse and
can be Found mainly where
the tooth is but is also
visible where the tooth
isn'é

e)

Needle like tracks

from 40 min and 80 min
etehings seem to be buried in sections where
the dentine of the tooth

was

r)

photomicrozraphs and

polaroid shots of tracks
on the viewing sereen
were

is

taken

2009443

bo}

though the 41 foil has a high
chemical purity,

U contamina-

tion can easiiy come about

through contact with
phere, etc.
c)

the atmos-

due to inadequate contact, images
of the dentine, pulp, enamel are
not distinguishable

d) agpregates could be clusters

of Pu in the teeth or resulting
from background U-238 converSion to Pu-23%

Select target paragraph3