Institution
Sandia National Laboratories
Facility•Livermore, California, United States•
About: Sandia National Laboratories is a facility organization based out in Livermore, California, United States. It is known for research contribution in the topics: Laser & Thin film. The organization has 21501 authors who have published 46724 publications receiving 1484388 citations. The organization is also known as: SNL & Sandia National Labs.
Topics: Laser, Thin film, Hydrogen, Combustion, Silicon
Papers published on a yearly basis
Papers
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TL;DR: In this article, a transient, multi-dimensional model has been developed to simulate proton exchange membrane (PEM) fuel cells, which accounts simultaneously for electrochemical kinetics, current distribution, hydrodynamics and multi-component transport.
Abstract: A transient, multi-dimensional model has been developed to simulate proton exchange membrane (PEM) fuel cells. The model accounts simultaneously for electrochemical kinetics, current distribution, hydrodynamics and multi-component transport. A single set of conservation equations valid for flow channels, gas-diffusion electrodes, catalyst layers and the membrane region are developed and numerically solved using a finite-volume-based computational fluid dynamics (CFD) technique. The numerical model is validated against published experimental data with good agreement. Subsequently, the model is applied to explore hydrogen dilution effects in the anode feed. The predicted polarization cubes under hydrogen dilution conditions are found to be in qualitative agreement with recent experiments reported in the literature. The detailed two-dimensional electrochemical and flow/transport simulations further reveal that in the presence of hydrogen dilution in the fuel stream, hydrogen is depleted at the reaction surface resulting in substantial kinetic polarization and hence a lower current density that is limited by hydrogen transport from the fuel stream to the reaction site.
729 citations
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University of Nantes1, University of Michigan2, Iowa State University3, ExxonMobil4, University of California, Santa Barbara5, University of Illinois at Urbana–Champaign6, Sandia National Laboratories7, Arizona State University8, University of Bath9, University of Tokyo10, University of Massachusetts Amherst11, Air Products & Chemicals12, Princeton University13
TL;DR: In this paper, the authors present a review of current theoretical approaches to adsorption phenomena in five specific classes of porous materials: oxide molecular sieves, porous coordination solids, porous carbons, sol−gel-derived oxides, and porous heteropolyanion salts.
Abstract: Tailoring of porous materials involves not only chemical synthetic techniques for tailoring microscopic properties such as pore size, pore shape, pore connectivity, and pore surface reactivity, but also materials processing techniques for tailoring the meso- and the macroscopic properties of bulk materials in the form of fibers, thin films, and monoliths. These issues are addressed in the context of five specific classes of porous materials: oxide molecular sieves, porous coordination solids, porous carbons, sol−gel-derived oxides, and porous heteropolyanion salts. Reviews of these specific areas are preceded by a presentation of background material and review of current theoretical approaches to adsorption phenomena. A concluding section outlines current research needs and opportunities.
722 citations
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TL;DR: In this article, a simplified version of the Perez[1] diffuse irradiance model is presented, which is one of those used currently to estimate short time step (hourly or less) irradiance on tilted planes based on global and direct (or diffuse) irradiances.
718 citations
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TL;DR: In this article, mineback experiments and laboratory tests and analyses of these data are integrated to describe this complex fracture behavior, which can occur by arresting the growth of the fracture, increasing fluid leakoff, hindering proppant transport, and enhancing the creation of multiple fractures.
Abstract: Geologic discontinuities, such as joints, faults, and bedding planes, can significantly affect the overall geometry of hydraulic fractures. This can occur by arresting the growth of the fracture, increasing fluid leakoff, hindering proppant transport, and enhancing the creation of multiple fractures. Results from mineback experiments and laboratory tests and analyses of these data are integrated to describe this complex fracture behavior.
718 citations
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TL;DR: This anisotropic swelling results in lithiated Si nanowires with a remarkable dumbbell-shaped cross section, which develops due to plastic flow and an ensuing necking instability that is induced by the tensile hoop stress buildup in the lithiated shell.
Abstract: We report direct observation of an unexpected anisotropic swelling of Si nanowires during lithiation against either a solid electrolyte with a lithium counter-electrode or a liquid electrolyte with a LiCoO2 counter-electrode. Such anisotropic expansion is attributed to the interfacial processes of accommodating large volumetric strains at the lithiation reaction front that depend sensitively on the crystallographic orientation. This anisotropic swelling results in lithiated Si nanowires with a remarkable dumbbell-shaped cross section, which develops due to plastic flow and an ensuing necking instability that is induced by the tensile hoop stress buildup in the lithiated shell. The plasticity-driven morphological instabilities often lead to fracture in lithiated nanowires, now captured in video. These results provide important insight into the battery degradation mechanisms.
713 citations
Authors
Showing all 21652 results
Name | H-index | Papers | Citations |
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Lily Yeh Jan | 162 | 467 | 73655 |
Jongmin Lee | 150 | 2257 | 134772 |
Jun Liu | 138 | 616 | 77099 |
Gerbrand Ceder | 137 | 682 | 76398 |
Kevin M. Smith | 114 | 1711 | 78470 |
Henry F. Schaefer | 111 | 1611 | 68695 |
Thomas Bein | 109 | 677 | 42800 |
David Chandler | 107 | 424 | 52396 |
Stephen J. Pearton | 104 | 1913 | 58669 |
Harold G. Craighead | 101 | 569 | 40357 |
Edward Ott | 101 | 669 | 44649 |
S. Das Sarma | 100 | 951 | 58803 |
Richard M. Crooks | 97 | 419 | 31105 |
David W. Murray | 97 | 699 | 43372 |
Alán Aspuru-Guzik | 97 | 628 | 44939 |