Rapid separation method for actinides in emergency air filter samples.
ABSTRACT A new rapid method for the determination of actinides and strontium in air filter samples has been developed at the Savannah River Site Environmental Lab (Aiken, SC, USA) that can be used in emergency response situations. The actinides and strontium in air filter method utilizes a rapid acid digestion method and a streamlined column separation process with stacked TEVA, TRU and Sr Resin cartridges. Vacuum box technology and rapid flow rates are used to reduce analytical time. Alpha emitters are prepared using cerium fluoride microprecipitation for counting by alpha spectrometry. The purified (90)Sr fractions are mounted directly on planchets and counted by gas flow proportional counting. The method showed high chemical recoveries and effective removal of interferences. This new procedure was applied to emergency air filter samples received in the NRIP Emergency Response exercise administered by the National Institute for Standards and Technology (NIST) in April, 2009. The actinide and (90)Sr in air filter results were reported in less than 4 h with excellent quality.
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ABSTRACT: A procedure is presented to provide sequential determination of isotopic strontium, thorium, plutonium, uranium, and americium in a single biological sample. The method begins with digestion and dissolution of the sample. Tracers and/or carriers are added to the sample for the purpose of chemical yield monitoring. Strontium is first separated from the actinides and from most of the interfering constituents of the sample by precipitation as carbonates. Strontium isotopes are purified, and 89Sr and 90Sr are measured by gas proportional counting. Actinides are separated and purified by ion exchange chromatography, co-precipitated with neodymium fluoride, filtered, and counted by alpha-particle spectrometry.Journal of Radioanalytical and Nuclear Chemistry 01/2000; 243(2):525-533. · 1.47 Impact Factor
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ABSTRACT: An automated system for on-line pre-concentration, separation and detection of plutonium in a urine sample was developed, based on the coupling of a multi-solvent delivery system, remotely- controlled switching modules, and an inductively coupled plasma mass spectrometer (ICP-MS). Effective separation between spectral and non-spectral interferences and Pu was performed via TEVA selective extraction chromatography. Pu elution from the resin was performed using 0.01 M (NH4)2C2O4, directed to the ICP-MS through a switching module controlled by the multi- solvent delivery unit. The automated flow injection system (AFIS) enables the quantification of Pu isotopes for urinalysis at the sub-mBq L � 1 range (DL: 0.21( 239 Pu), 0.19( 240 Pu) mBq L � 1 )i n less than 15 min, with a chemical recovery exceeding 70%. The simplicity, speed, and automation of this approach make it attractive for radiological emergency response, especially considering its high daily sample throughput (480). This throughput is the result of the faster flow rate used for the separation (up to 3 mL min � 1 ) and the reusability of the extraction resin. If a calcium phosphate co-precipitation step is performed prior to loading the sample onto the TEVA resin, improvement in pre-concentration capacity is possible, making the AFIS usable for the assessment of occupational exposures.Journal of Analytical Atomic Spectrometry 01/2008; 23(3). · 3.16 Impact Factor
- Radiochimica Acta - RADIOCHIM ACTA. 01/2004; 92:467-473.