The separation and purification of americium-241 (25 mg.), produced by the @-decay of plutonium-241 in plutonium containing small amounts of the latter isotope, is described.The absorption spectra of americium(rr1) in perchloric acid and in hydrochloric acid have been measured. The narrow 504-mp peak does not obey either Beer's or Lambert's law ; the 814-mp peak obeys both.By following changes in the absorption spectra the disproportionation and self-reduction of americium(v) in hydrochloric acid have been observed. Self-reduction is caused by reducing materials produced in solution by a-particle bombardment. In low acid concentrations only self-reduction occurs, but in more concentrated acid solutions disproportionation predominates.

This work presents the findings of a long-term plutonium (Pu) study at Savannah River Site (SRS) conducted between 2003 and 2013. Terrestrial environmental samples were obtained at the Savannah River National Laboratory (SRNL) in the A-Area. Plutonium content and isotopic abundances were measured over this time period by α particle and thermal ionization mass spectrometry (3STIMS). We detail the complete process of the sample collection, radiochemical separation, and measurement procedure specifically targeted to trace plutonium in bulk environmental samples. Total plutonium activities were determined to be not significantly above atmospheric global fallout. However, the (238)Pu/(239+240)Pu activity ratios attributed to SRS are substantially different than fallout due to past (238)Pu production on the site. The (240)Pu/(239)Pu atom ratios are reasonably consistent from year to year and are lower than fallout indicating an admixture of weapons-grade material, while the (242)Pu/(239)Pu atom ratios are higher than fallout values, again due to actinide production activities. Overall, the plutonium signatures obtained in this study reflect a distinctive mixture of weapons-grade, heat source, and higher burn-up plutonium with fallout material. This study provides a unique opportunity for developing and demonstrating a blue print for long-term low-level monitoring of trace plutonium in the environment.

Hall and Streat. 5205 993. Radiation-induced Decomposition of lon-exchange Resins. Part I . Anion-exchange Resins.

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