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Abstract  

Although many areas of major national need depend critically on professionals trained in nuclear and radiochemistry, educational opportunities and student interest in this area have declined steadily for the last twenty years. One major contributing factor to the lack of student interest is that most students in science and chemistry courses are never introduced to these topics. This deficiency in science curricula, coupled with the negative public perception towards all things nuclear, has resulted in a serious shortage of individuals with a background in this area. We propose to address this problem by educating the educators — providing faculty from two- and four-year colleges and high school science teachers with the curriculum materials, training, and motivation to incorporate these topics on a continuing basis in their curricula. Two advantages of this approach are: (1) it will generate scientists with a basic understanding of this field and (2) as teachers incorporate nuclear topics, many students will have the opportunity to reflect on the role of science in a technological society.

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Summary  

We present the outline of a comprehensive website based offering of a basic graduate level or senior undergraduate level course in nuclear and radiochemistry. This password protected course follows classical pedagogical treatment of the subject. However, it has been augmented by the implementation of Flash animations to better teach basic nuclear and radiochemistry concepts. As well, the website is linked to many Internet related resources. All lectures and problems are presented in Microsoft Power Point format with Flash animations incorporated. A series of six experiments in radiochemistry, also offered in the course is available in a downloadable Microsoft Word format.

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Abstract  

Three different spent control rods were obtained for direct-assay measurements and empirical sampling and analysis. They were: 1) a BWR cruciform control rod, 2) a PWR rod-cluster control assembly, and 3) a burnable poison-rod assembly. The dominant activity of the BWR cruciform control rod and the PWR burnable poison-rod assembly is60Co, whereas the PWR rod-cluster control assembly is dominated not only by60Co, but also by108mAg and110mAg, which are found in the Ag–In–Cd alloy of the absorber rods. The radionuclide inventories calculated for the three spent control rods from the empirical sampling data agree very well with data determined from the two direct assay methodologies. The concentration of108mAg in the rod-cluster control assembly will have to be considered when these types of spent control rods are prepared for waste disposal.

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Acta Mathematica Hungarica
Authors: C. Campbell, E. Robertson, M. Ruškuc, and R. Thomas
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Journal of Radioanalytical and Nuclear Chemistry
Authors: E. Lepel, W. Hensley, J. Boatman, K. Busness, W. Davis, D. Robertson, and W. Slinn

Abstract  

Airborne gamma-ray measurements were made aboard the Pacific Northwest Laboratory (PNL) DC-3 and the National Oceanic and Atmospheric Administration (NOAA) King Air research aircraft before and during the first passage of the Chernobyl radioactive cloud over the west coast of the North American continent. Measurements were made from Anchorage, Alaska south to Reno, Nevada. Calculated trajectories were used to estimate the location of the Chernobyl plume. The in-situ gamma-ray analysis systems first detected the cloud on May 8, 1986. Subsequent analysis of concurrently collected air filters indicated that the leading edge of the plume was just reaching the west coast of the United States on May 6, 1986. The ratios of the observed volatile radionuclides (131I and134Cs normalized to137Cs) agreed with the reported discharge ratio.

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Summary  

Selenium is a required trace-element that has been found to be protective against serious chronic diseases such as cancer and cardiovascular disease in some, but not all, epidemiological studies using both case-control and intervention designs. As a result, the fraction of the adult U.S. population now taking a daily selenium supplement is steadily increasing. In this study, we analyzed 10 or more replicate Se supplement tablets, from each of 15 different products representing 12 different brand names with most being sampled at two different times separated by approximately 30 months. Two chemical forms, seleno-yeast and selenate were tested in 50, 100 and 200 µg/tablet dosages (seleno-yeast) and 25 and 200 µg/tablet dosages (selenate). Variations in contemporary lots were evaluated at both sampling periods. The Se content provided on the product label is generally understated. One tablet contained 2.5 times more selenium than the stated dose. Selenate supplements are less accurately labeled and more highly variable compared to yeast supplements. One popular multivitamin, labeled at 200 µg/tablet, contained tablets in excess of 300 µg. Many subjects using this supplement will exceed the 400 µg/day tolerable upper limit of intake, recently established, for Se by the Institute of Medicine’s Food and Nutrition Board.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: D. Robertson, A. Schilk, K. Abel, E. Lepel, C. Thomas, S. Pratt, E. Cooper, P. Hartwig, and R. Killey

Abstract  

In order to more accurately predict the rates and mechanisms of radionuclide migration from lowlevel waste disposal facilities via groundwater transport, ongoing studies are being conducted at field sites at Chalk River Laboratories to identify and characterize the chemical speciation of mobile, long-lived radionuclides migrating in groundwaters. Large-volume water sampling techniques are being utilized to separate and concentrate radionuclides into particulate, cationic, anionic, and nonionic chemical forms. Most radionuclides are migrating as soluble, anionic species which appear to be predominately organoradionuclide complexes. Laboratory studies utilizing anion exchange chromatography have separated several anionically complexed radionuclides, e.g.,60Co and106Ru, into a number of specific compounds or groups of compounds. Large-volume ultra-filtration experiments have shown that significant fractions of the radionuclides are being transported in these groundwaters in the form of macromolecules having molecular weights ranging from less than 3,000 to 100,000.

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