The uptake and the long term behavior of Cs-137, Cs-134 and K-40 in the annual tree rings of spruce were examined. The youngest tree rings which are most active in water transport have higher activity concentrations, of K-40 and of radiocesium than the older ones. The activity concentration of Cs-137 in a water transporting tree ring can be well described as a function of the activity concentration of K-40. Furthermore a depth profile of the soil was taken and gives information, about the depth distribution of radiocesium and K-40.
In this work the transfer behavior of long living radionuclides from the Thorium decay series (Ra-228, Th-228, Th-232) as well as of K-40 and Cs-137 is studied. In a small area of middle Europe (southeast Gemany) showing an increased Thorium content of soil the activity concentrations in samples of feed plants, farm animals, farm animal products, roe deer has been determined. The concentration ratios feed-to-animal tissue and to animal products are calculated indicating a significantly enhanced transfer from feed to roe deer tissues. Determinations of the activity concentrations in fish (carp), pig (tissues), egg, milk complete this examinations. Among all studied samples which are important for human nourishing eggs and carp cause the greatest exposure by ingestion.
The uptake and the radial distribution of naturally occurring radionuclides in the tree rings of a spruce tree were examined. The activity concentrations of Pb-210 are at a constant level of about 1,7 Bq/kg dry weight (dw) in older tree rings but decrease to younger ones. We suggest that Rn-222 dissolved in the soil water is taken up in significant amounts by the tree roots and decays to Pb-210 within the wood. The activity concentrations of Ra-226 of about 2,0 Bq/kg (dw) are nearly constant over all tree rings. Ra-228 however showed a significantly different behavior. Futhermore the activity concentrations of U-, Th- and Pu-isotopes were determined. A depth profile of the soil within the root zone of the spruce gives further informations.
Authors:A. Plionis, D. Haas, S. Landsberger, and G. Brooks
Several methods for the electrodeposition of actinides for alpha-spectrometry analysis have been developed over the past few
decades, but none have been specifically designed to facilitate rapid analysis in a field situation. This paper describes
the development of an electrodeposition procedure that is specifically adapted for use in a mobile lab. Using these techniques
one would be able to obtain preliminary results in the event of a radiological incident. Quantitative yields with associated
uncertainties have been determined for the procedure. It has also been shown that short deposition times can provide quantitative
Authors:P. Grant, K. Moody, I. Hutcheon, D. Phinney, R. Whipple, J. Haas, A. Alcaraz, J. Andrews, G. Klunder, R. Russo, T. Fickies, G. Pelkey, B. Andresen, D. Kruchten, and S. Cantlin
Over the past several years, the Livermore Forensic Science Center has conducted analyses of nuclear-related samples in conjunction
with domestic and international criminal investigations. Law enforcement officials have sought conventional and nuclear-forensic
analyses of questioned specimens that have typically consisted of miscellaneous metal species or actinide salts. The investigated
activities have included nuclear smuggling and the proliferation of alleged fissionable materials, nonradioactive hoaxes such
as “Red Mercury,” and the interdiction of illegal laboratories engaged in methamphetamine synthesis.