Publications by authors named "Ashlee Swindle"

Field experiments were performed to evaluate the deposition velocity of tritium oxide within a forest environment at the Savannah River Site near Aiken, SC. Field releases were designed to guide selection of deposition velocity values for use in safety-basis modeling. Six releases of deuterium oxide were conducted in 2020 and 2021 with corresponding air samples during and following each release.

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Rapid detection of nerve agents from complex matrices with minimal sample preparation is essential due to their high toxicity and bioavailability. In this work, quantum dots (QDs) were functionalized with oligonucleotide aptamers that specifically targeted a nerve agent metabolite, methylphosphonic acid (MePA). These QD-DNA bioconjugates were covalently linked to quencher molecules to form Förster resonance energy transfer (FRET) donor-acceptor pairs that quantitatively measure the presence of MePA.

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Ultra-low-level measurements of radionuclides in air have been conducted at the Savannah River National Laboratory (SRNL) to determine the atmospheric concentration of fission products released following the Fukushima Daiichi reactor accident on March 11, 2011. Air filter samples were acquired from two high-volume collection systems (a traditional filter-based system and an electrostatic precipitator-based system) to monitor airborne radionuclide concentrations in the period covering from 2 weeks to 3 years after the disaster. The world-wide spread of low-level concentrations of airborne fission products from the Fukushima event provided a unique opportunity to demonstrate SRNL's electrostatic particle collection technology and other improvements in environmental monitoring developed at the Savannah River Site (SRS).

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The speciation of radioactive tritium (T) in a naturally-established subtropical loblolly pine forest that has been irrigated with highly-contaminated pond water for the last 20 years is reported. This irrigation project was created to limit the underground transport of a tritium-rich plume which also contains low levels of toxic organics, metals and radionuclides such as carbon-14 (14C) from a nearby low-level waste burial ground. The levels of tritiated water (HTO) in the wood cores were not influenced by recent irrigation activities.

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