A5054258025- Radioactive element chemistry and processing
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Radioactive contamination and transfer
- Nuclear Materials and Properties
- Nuclear reactor physics and engineering
- Nuclear Physics and Applications
- Nuclear and radioactivity studies
- Extraction and Separation Processes
- Chemical Synthesis and Characterization
- Crystallography and molecular interactions
- Isotope Analysis in Ecology
- Analytical chemistry methods development
- Molecular Sensors and Ion Detection
- Chemical Thermodynamics and Molecular Structure
- Chemical and Physical Properties in Aqueous Solutions
- Nuclear physics research studies
- Aerosol Filtration and Electrostatic Precipitation
- Radiative Heat Transfer Studies
- Radioactivity and Radon Measurements
- Gamma-ray bursts and supernovae
- Radioactive Decay and Measurement Techniques
- Scientific Measurement and Uncertainty Evaluation
- Pesticide Residue Analysis and Safety
- Mass Spectrometry Techniques and Applications
Oak Ridge National Laboratory
2012-2024
National Technical Information Service
2021-2023
Office of Scientific and Technical Information
2021-2023
Government of the United States of America
2022
University of Edinburgh
2010-2022
Lawrence Livermore National Laboratory
2021
The determination of trace elements, particularly rare earth in uranium ore concentrates (UOCs) is important as the pattern can be indictive characteristics. Presented here a methodology for accurately quantifying elements (REE) UOCs. To improve measurement uncertainty, isotope dilution mass spectrometry (IDMS) was utilized over other quantification techniques such external calibration or standard addition. isotopic determinations were measured by inductively coupled plasma-mass (ICP-MS)....
A series of 3-substituted salicylaldoximes has been used to demonstrate the importance outer-sphere interactions on efficacy solvent extractants that are produce approximately one-quarter world's copper. The distribution coefficient for extraction copper by 5-tert-butyl-3-X-salicylaldoximes (X = H, Me, (t)Bu, NO(2), Cl, Br, OMe) varies more than two orders magnitude. X-ray structure determinations preorganized free ligand dimers (10 new structures reported) indicate substituents with a...
Square planar complexes of the type Ni(L1)2, Ni(L2)2, Cu(L1)2, and Cu(L2)2, where L1H = 2-hydroxy-5-t-octylacetophenone oxime L2H 2-hydroxy-5-n-propylacetophenone oxime, have been prepared characterized by single-crystal X-ray diffraction, cyclic voltammetry, UV/vis spectroscopy, field-effect-transistor measurements, density functional theory (DFT) time-dependent DFT (TDDFT) calculations, and, in case paramagnetic species, electron resonance (EPR) magnetic susceptibility. Variation alkyl...
NiSO4 and FeSO4 self-assemble with heteroditopic ligands (L) comprising 2,2′-bipyridine o-phenylene-(bis)urea cation- anion-binding sites, respectively, into [ML3SO4] (M = Ni2+, Fe2+) triple-stranded ion-pair helicates mesocates.
The purity, concentration, and source of the N,N′-dicyclohexyl-N″-isotridecylguanidine (DCiTG) suppressor (guanidine) used in NG-CSSX process were found to influence solvent performance. As starting isotridecanol preparation DCiTG is comprised a mixture branched-chain aliphatic alcohols, varying composition with manufacturer, resulting itself mixture. Thus, it necessary address how performance will be affected by different preparations component. In this study, four from three sources...
It is shown in this work that the solvent used Next Generation Caustic-Side Solvent Extraction (NGS) process can withstand a radiation dose well excess of it would receive multiple years treating legacy salt waste at US Department Energy Savannah River Site. The was subjected to maximum 50 kGy gamma while dynamic contact with each aqueous phases current NGS process, namely SRS−15 (a highly caustic simulant), sodium hydroxide scrub solution (0.025 M), and boric acid strip (0.01 M). Bench-top...
The ability to directly measure uranium isotope ratios on environmental swipes has been achieved through a solution-based microextraction process and represents significant advancement toward the development of rapid method analyze international nuclear safeguard samples. Here, probe is lowered sealed onto swipe surface, analytes within sampling site (∼8 mm2) are dissolved extracted into flowing solvent 2% nitric acid (HNO3). mobilized species subsequently directed an inductively coupled...
This study demonstrates a method for determining the isotopic composition of low-level (sub-pg) plutonium (Pu) directly from cotton swipe.
As part of the ongoing development Next-Generation Caustic-Side Solvent Extraction (NG-CSSX) process, thermal stability its process solvent, (NGS) was investigated and shown to be adequate for industrial application. The solvent thermally treated at 35°C over a period 13 months whilst in dynamic contact with each aqueous phases current NG-CSSX namely SRS−15 (a highly caustic waste simulant), sodium hydroxide scrub solution (0.025 M), boric acid strip (0.01 M). effect treatment evaluated by...
Here we present the application of a novel analytical approach for high-speed evaluation burn-up in spent nuclear fuel. This automated online separation–direct analysis method, which simultaneously measures isotopic compositions and concentrations Nd, Pu, U using isotope dilution-inductively coupled plasma mass spectrometry, enables determination burnup as little 4.5 h per sample with expanded uncertainties low 1.2% 1µg We compare determined values, requirements, times an ultra-high...
Ligand–ligand interactions in the outer coordination sphere make an important contribution to effects of 3-substituents on stabilities anionic Cu(II) salicylaldoximato complexes [CuL(L-H)]−. When substituents contain a different number bonds interpretation CID tandem mass spectrometry must take into account ability ions redistribute energy acquired collisions within numbers vibrational modes.
Salicylaldehyde hydrazones are weaker copper extractants than their oxime derivatives, which used in hydrometallurgical processes to recover ~20 % of the world’s copper. Their strength, based on extraction equilibrium constant Ke, can be increased by nearly three orders magnitude incorporating electron-withdrawing or hydrogen-bond acceptor groups (X) ortho phenolic OH group salicylaldehyde unit. Density functional theory calculations suggest that effects 3-X substituents arise from a...
Conditions have been identified in which phenolic aldoximes and ketoximes of the types used commercial solvent extraction processes can be doubly deprotonated generate polynuclear Cu complexes with lower extractant:Cu molar ratios than those found operations. Electrospray mass spectrometry has provided an insight into solution speciation experiments conditions to allow isolation characterization Cu-complexes. Elevation pH is effective enhancing formation trinuclear containing planar...