Oxygen Isotope Alterations during the Reduction of UO to UO for Nuclear Forensics Applications.

The fabrication of UO from UO is an essential reaction in the nuclear fuel cycle. The oxygen isotope fractionation associated with this reaction has significant implications in the general field of nuclear forensics. Hence, the oxygen isotope fractionation during the reduction of UO to UO was determined in the temperature range of 500-700 °C and for a duration of 2 to 6 h under a high-purity H atmosphere.

Equilibrium Fractionation of Oxygen Isotopes in the UO-Atmospheric Oxygen System.

As a major component in the nuclear fuel cycle, octoxide uranium is subjected to intensive nuclear forensics research. Scientific efforts have been mainly dedicated to determine signatures, allowing for clear and distinct attribution. The oxygen isotopic composition of octoxide uranium, acquired during the fabrication process of the nuclear fuel, might serve as a signature.

Oxygen Isotopic Composition of UO Synthesized From U Metal, Uranyl Nitrate Hydrate, and UO as a Signature for Nuclear Forensics.

Triuranium octoxide (UO) is one of the main compounds in the nuclear fuel cycle. As such, identifying its processing parameters that control the oxygen isotopic composition could be developed as a new signature for nuclear forensic investigation. This study investigated the effect of different synthesis conditions such as calcination time, temperature, and cooling rates on the final δO values of UO, produced from uranium metal, uranyl nitrate hydrate, and uranium trioxide as starting materials.

Determination of Uranium Isotopic Ratio by ICP-OES Using Optimal Sensitivity Position Analysis.

Isotopic composition analysis of natural and depleted uranium by inductively coupled plasma optical emission spectrometry (ICP-OES) requires the use of a high-resolution instrument due to the very slight isotopic shifts between the atomic emission spectra of the U and U isotopes. In this work, we show that conventional ICP-OES (without high-resolution optics) can be used for highly accurate uranium isotopic analysis, on par with the results obtained by ICP-MS. Such accurate measurements are achieved by applying a preparatory mathematical procedure termed the optimal sensitivity position (OSP) procedure.

Visual observations of an atmospheric-pressure solution-cathode glow discharge.

The solution-cathode glow discharge (SCGD) is an optical emission source for atomic spectrometry comprised of a moderate-power atmospheric-pressure DC glow discharge sustained directly upon the surface of an electrically conductive solution. The SCGD boasts a simple, inexpensive design and has demonstrated detection limits similar to those of more conventional excitation sources used in atomic spectrometry. Although the analytical performance of the SCGD as an optical emission source is well characterized, the mechanism through which the discharge atomizes and excites analyte from the sample solution remains a point of debate.

Quantification of trace metals in water using complexation and filter concentration.

Various metals undergo complexation with organic reagents, resulting in colored products. In practice, their molar absorptivities allow for quantification in the ppm range. However, a proper pre-concentration of the colored complex on paper filter lowers the quantification limit to the low ppb range.