Vp. Perelygin et Yt. Chuburkov, ON THE DETERMINATION OF LOW PU CONTENT IN THE ENVIRONMENT, Nuclear tracks & radiation measurements, 22(1-4), 1993, pp. 869-872
The method of Pu-239 minor content determination in the soil, water, a
ir, living species is developed. It is based on chemical extraction of
plutonium from the specimens. The Pu-236 alpha-active tracer was used
to control the chemical yield of Pu from samples. The layers with Pu
were put in contact with polyterephtalate and irradiated with thermal
neutron fluences approximately 10(15) cm-2 together with calibrated U
and P ethalons. The Pu content in soils from North Ukraina region was
310(-12) - 1.210(-13) g/g. To check the possible Th-U minor admixtures
of U and Th in Pu fractions, the control experiments with 23 MeV gamm
a-rays were carried out. It provides an upper limit of admixture of th
ese nuclei at the level of less-than-or-equal-to 10(8) per sample.