A5076183522- Spectroscopy and Quantum Chemical Studies
- Glass properties and applications
- CO2 Sequestration and Geologic Interactions
- Crystallization and Solubility Studies
- Nuclear materials and radiation effects
- Chemical and Physical Properties in Aqueous Solutions
- X-ray Diffraction in Crystallography
- Hydrocarbon exploration and reservoir analysis
- Chemical Synthesis and Characterization
- Recycling and utilization of industrial and municipal waste in materials production
- Clay minerals and soil interactions
- Radioactive element chemistry and processing
- Geological and Geochemical Analysis
- Laser-Matter Interactions and Applications
- Iron oxide chemistry and applications
- Bauxite Residue and Utilization
- Cultural Heritage Materials Analysis
- Luminescence Properties of Advanced Materials
- Mass Spectrometry Techniques and Applications
- Advanced NMR Techniques and Applications
- Carbon Dioxide Capture Technologies
- Adsorption and biosorption for pollutant removal
- Material Dynamics and Properties
- Electrochemical Analysis and Applications
- NMR spectroscopy and applications
Pacific Northwest National Laboratory
2020-2025
Government of the United States of America
2025
Savannah River National Laboratory
2024
Battelle
2023
Washington State University
2019-2021
Physical Sciences (United States)
2021
Richland College
2020
Attosecond-pump/attosecond-probe experiments have long been sought as the most straightforward method for observing electron dynamics in real time. Although there has much success with overlapped near-infrared femtosecond and extreme ultraviolet attosecond pulses combined theory, true attosecond-pump/attosecond-probe limited. We used a synchronized x-ray pulse pair from an free-electron laser to study electronic response valence ionization liquid water through all transient absorption...
This study evaluated zeolite-based sorbents for iodine gas [I2(g)] capture. Based on the framework structures and porosities, five zeolites, including two faujasite (FAU), one ZSM-5 (MFI), mesoMFI, ZSM-22 (TON), as well mesoporous materials, were I2(g) capture at room temperature 150 °C in an iodine-saturated environment. From these preliminary studies, three best-performing zeolites ion-exchanged with Ag+ under similar conditions. Energy-dispersive X-ray spectroscopy data suggest that...
Locating and developing ideal sites for large-scale capture storage of carbon dioxide has become increasingly necessary due to increasing global emissions warming. Mafic–ultramafic rocks present a unique geologic setting as they can trap injected CO2 in pore space, mineralize that permanently store it carbonate minerals, simultaneously release critical minerals. However, these reservoirs are undercharacterized relative sedimentary settings. In this study, we execute methodology determining...
We establish the connection between measured small angle x-ray scattering signal and charge–charge correlations underlying Kirkwood transitions (KTs) in 1:1, 2:1, 3:1 aqueous electrolytes. These measurements allow us to obtain underscreening lengths for bulk electrolytes independently verified by theory simulations. Furthermore, we generalize concept of KTs beyond those theoretically predicted 1:1 electrolytes, which involves inverse screening length, a0, periodicity Q0. Above KTs, find a...
As part of the US Department Energy's push to accelerate commercialization CO2 removal, Pacific Northwest National Laboratory and Lawrence Livermore are creating life cycle assessment inclusive monitoring, reporting, verification protocols for all forms mineralization-based carbon dioxide removal. These protocols—produced in partnership with dozens partners from industry, government, local communities—are meant ensure that claimed removals quantitatively verified based on rigorous science...
Basalt reservoirs offer the potential for carbon mineralization, aiding in achieving net-zero emissions. However, debates persist about microscopic crystallization mechanisms due to limited characterization techniques under high-temperature and pressure conditions. By using Identical Location Transmission Electron Microscopy (IL-TEM) cryo-TEM, this study reveals nanoscale interfacial carbonation processes of forsterite diopside nanoparticles water-saturated supercritical dioxide realistic...
Greigite (Fe3S4) particles, with strong ferrimagnetic behavior, have been found to desirable uses in the areas of biomedical and environmental applications. Size-dependent magnetic properties greigite can play a crucial role efficiency its This study reviews two synthetic approaches producing such particles. The methods tested within this include coprecipitation synthesis hydrothermal process. While method proved be ineffective at greigite, process showed promise after consistently greigite....
Mechanism of hexavalent chromium removal (Cr(VI) as CrO42-) by the weak-base ion exchange (IX) resin ResinTech® SIR-700-HP (SIR-700) from simulated groundwater is assessed in presence radioactive contaminants iodine-129 (as IO3-), uranium (U uranyl UO22+), and technetium-99 TcO4-), common environmental anions sulfate (SO42-) chloride (Cl-). Batch tests using acid form SIR-700 demonstrated Cr(VI) U(VI) exceeded 97%, except high SO42- concentrations (536 mg/L) where decreased to ≥ 80%....
Understanding multiple lengthscale correlations in the pair distribution functions (PDFs) of aq. electrolytes is a persistent challenge. Here, coordination chemistry polyoxoanions supports an ion-network cation-coordination polyhedra NaNO3(aq) and NaNO2(aq) that induce long-range solution structure. Oxygen associated with Na+-coordination have two characteristics lengthscales; 3.5-5.5 Å 5.5-7.5 Å, latter solely oligomers. The PDF contraction between observed many attributed to distinct O⋯O...
Abstract Non-ideal thermodynamics of solid solutions can greatly impact materials degradation behavior. We have investigated an actinide silicate solution system (USiO 4 –ThSiO ), demonstrating that thermodynamic non-ideality follows a distinctive, atomic-scale disordering process, which is usually considered as random distribution. Neutron total scattering implemented by pair distribution function analysis confirmed model for U and Th in first three coordination shells; however,...
The dynamics, orientational anisotropy, diffusivity, viscosity, and density were measured for concentrated lithium salt solutions, including chloride (LiCl), bromide (LiBr), nitrite (LiNO2), nitrate (LiNO3), with methyl thiocyanate as an infrared vibrational probe molecule, using two-dimensional spectroscopy (2D IR), nuclear magnetic resonance (NMR) spectroscopy, viscometry. 2D IR, NMR, viscosity results show that LiNO2 exhibits longer correlation times, lower nearly 4 times greater compared...
The solubility and spectroscopy of sodium nitrite in hydroxide solutions are detailed to provide insight into processes underlying solubility.
Ultraviolet (UV) photolysis of nitrite ions (NO2-) in aqueous solutions produces a suite radicals, viz., NO·, O-, ·OH, and ·NO2. The O- NO· radicals are initially formed from the dissociation photoexcited NO2-. radical undergoes reversible proton transfer with water to generate ·OH. Both ·OH oxidize NO2- ·NO2 radicals. reactions occur at solution diffusion limits, which influenced by nature dissolved cations anions. Here, we systematically varied alkali metal cation, spanning range strongly...
Ion-ion correlations, screening, and equilibrium bulk structure in various concentrated electrolytes are investigated using synchrotron small angle X-ray scattering (SAXS), theory, molecular simulation. Utilizing SAXS measurements we provide estimates of the Kirkwood Transition (KT) for a variety aqueous (NaCl, CaCl$_2$, SrCl$_2$, ErCl$_3$). The KT may be defined as concentration above which ion-ion correlations cease to decay exponentially with single length scale given by Debye...