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Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
ReGa crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Re is bonded to six equivalent Re and six equivalent Ga atoms to form distorted ReGa6Re6 cuboctahedra that share corners with eighteen equivalent ReGa6Re6 cuboctahedra, edges with six equivalent ReGa6Re6 cuboctahedra, edges with twelve equivalent GaGa6Re6 cuboctahedra, faces with eight equivalent ReGa6Re6 cuboctahedra, and faces with twelve equivalent GaGa6Re6 cuboctahedra. All Re–Re bond lengths are 2.89 Å. All Re–Ga bond lengths are 2.65 Å. Ga is bonded to six equivalent Re and six equivalent Ga atoms to form distorted GaGa6Re6 cuboctahedra that share corners with eighteen equivalent GaGa6Re6 cuboctahedra, edges with six equivalent GaGa6Re6 cuboctahedra, edges with twelve equivalent ReGa6Re6 cuboctahedra, faces with eight equivalent GaGa6Re6 cuboctahedra, and faces with twelve equivalent ReGa6Re6 cuboctahedra. All Ga–Ga bond lengths are 2.89 Å.
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Dense, granular flows were examined to effectively capture and model bulk viscous properties in thin packed beds. A modified Couette cell with particle image velocimetry was used to experimentally determine pseudo-viscosity properties of four particulate media with varying morphologies: (1) iron oxide-coated SiO 2 particles, (2) CARBOBEAD CP30-60 particles, (3) CARBOBEAD CP40-100 particles, and (4) Al 2 O 3 beads. The pseudo-viscosity functions were fitted using a power law to correlate the measured shear stress as a function of measured shear rate. The pseudo-viscous functions were used as inputs to computation fluid dynamics models for a single-phase viscous fluid to predict granular flow profiles. Steady-state free surface velocity profiles at angular velocities <7 rad/s predicted by the model were in good agreement with the experimental particle image velocimetry measurements, resulting in Pearson correlation coefficients of 0.97 for iron-oxide coated SiO 2 particles and 0.95 for CP30-60 particles. As a result, this alternative approach to measuring pseudo-viscous properties under shearing and modeling bulk transport behavior of granular flow using computation fluid dynamics model offered significant reduction in computational load compared to discrete element methods.
Efficient thermal energy storage is pivotal to lowering the levelized cost of electricity (LCOE) for Concentrating Solar Power (CSP) plants. In solid-particle systems, however, prolonged high-temperature service degrades particle solar absorptivity, eroding overall efficiency. This project demonstrates a hydrogen-assisted recovery process that reliably restores absorptivity to >90 %, offering a practical route to sustain long-term CSP performance. Bench-scale investigations mapped the reduction kinetics of optically faded particles across hydrogen concentrations, temperatures, and residence times. Coupling mass-spectrometric monitoring with machine-learning optimization minimized energy demand while maximizing absorptivity gain. The resulting process window—moderate hydrogen partial pressures, 15–30 min dwell times, and temperatures well below initial calcination levels—cuts energy consumption well below that of incumbent re-blackening methods. A prototype recovery reactor processed multiple 2 kg batches with repeatable outcomes, confirming scalability and operational robustness. Integrated techno-economic analysis indicates material and operating cost reductions exceeding 15 % relative to conventional particle replacement or chemical re-coating, translating directly into lower LCOE for next-generation CSP facilities. By uniting fundamental reaction-kinetics insight with pragmatic engineering, this work advances the solid-particle pathway, delivering a cost-effective, field-deployable solution to one of CSP’s key durability challenges and strengthening the commercial outlook for high-temperature renewable power.
Impact of pore scale geochemical reactions on evolution of hydraulic and mechanical properties in CO2 storage systems.
Evolution of Transport and Mechanical Properties of Different Mineral Dissolution Patterns.
Coupled geochemical-geomechanical processes in CO2 sequestration reservoirs in Southeast, US
Coupled geochemical-geomechanical alteration of sandstone in CO2 sequestration reservoirs.
Geomechanical response of CO2 sequestration reservoirs due to different carbonate dissolution patterns
Coupled geochemical-geomechanical processes in CO2 sequestration reservoirs in Southeast, US