scispace - formally typeset
Search or ask a question
Institution

Sandia National Laboratories

FacilityLivermore, 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 & Combustion. The organization has 21501 authors who have published 46724 publications receiving 1484388 citations. The organization is also known as: SNL & Sandia National Labs.


Papers
More filters
Journal ArticleDOI
TL;DR: In this paper, two methods for estimating the fractal dimension of a profile of a rough surface are compared, the divider method and the spectral method, and it is shown that the two methods yield the same results, if the horizontal resolution at which the profile is measured is smaller than the crossover length.
Abstract: Self-affine fractals are useful models of the surfaces of rock fractures. The scaling properties of these surfaces are described by two parameters, the fractal dimension and the crossover length. Two methods for estimating the fractal dimension of a profile of a rough surface are compared, the divider method and the spectral method. It is shown that the two methods yield the same results, if the horizontal resolution at which the profile is measured is smaller than the crossover length. However, for resolutions greater than the crossover length, the divider method always gives a fractal dimension close to 1. To guide future work, the crossover length is estimated for typical joint surfaces and for the San Andreas fault. Additionally, a simple method is proposed to obtain the correct fractal dimension without prior knowledge of the crossover length. copyright American Geophysical Union 1987

225 citations

Journal ArticleDOI
TL;DR: The quantitative results unambiguously confirm the mosaic (particle-by-particle) pathway of intercalation and suggest that the rate-limiting process of charging is initiating the phase transformation by, for example, a nucleation-like event.
Abstract: The intercalation pathway of lithium iron phosphate (LFP) in the positive electrode of a lithium-ion battery was probed at the ∼40 nm length scale using oxidation-state-sensitive X-ray microscopy. Combined with morphological observations of the same exact locations using transmission electron microscopy, we quantified the local state-of-charge of approximately 450 individual LFP particles over nearly the entire thickness of the porous electrode. With the electrode charged to 50% state-of-charge in 0.5 h, we observed that the overwhelming majority of particles were either almost completely delithiated or lithiated. Specifically, only ∼2% of individual particles were at an intermediate state-of-charge. From this small fraction of particles that were actively undergoing delithiation, we conclude that the time needed to charge a particle is ∼1/50 the time needed to charge the entire particle ensemble. Surprisingly, we observed a very weak correlation between the sequence of delithiation and the particle size,...

225 citations

Journal ArticleDOI
TL;DR: In this article, the authors induced sublimation of suspended few-layer graphene by in situ Joule-heating inside a transmission electron microscope and observed a fractal-like “coastline” morphology.
Abstract: We induced sublimation of suspended few-layer graphene by in situ Joule-heating inside a transmission electron microscope. The graphene sublimation fronts consisted of mostly {1100} zigzag edges. Under appropriate conditions, a fractal-like “coastline” morphology was observed. Extensive multiple-layer reconstructions at the graphene edges led to the formation of unique carbon nanostructures, such as sp2-bonded bilayer edges (BLEs) and nanotubes connected to BLEs. Flat fullerenes/nanopods and nanotubes tunneling multiple layers of graphene sheets were also observed. Remarkably, >99% of the graphene edges observed during sublimation are BLEs rather than monolayer edges (MLEs), indicating that BLEs are the stable edges in graphene at high temperatures. We reproduced the “coastline” sublimation morphologies by kinetic Monte Carlo (kMC) simulations. The simulation revealed geometrical and topological features unique to quasi-2-dimensional (2D) graphene sublimation and reconstructions. These reconstructions were enabled by bending, which cannot occur in first-order phase transformations of 3D bulk materials. These results indicate that substrate of multiple-layer graphene can offer unique opportunities for tailoring carbon-based nanostructures and engineering novel nano-devices with complex topologies.

224 citations

Proceedings ArticleDOI
01 Dec 2011
TL;DR: The ParaView Coprocessing Library is described, a framework for in situ visualization and analysis coprocessed algorithms that can be linked and executed directly from within a scientific simulation or other applications that need visualization andAnalysis.
Abstract: As high performance computing approaches exascale, CPU capability far outpaces disk write speed, and in situ visualization becomes an essential part of an analyst's workflow. In this paper, we describe the ParaView Coprocessing Library, a framework for in situ visualization and analysis coprocessing. We describe how coprocessing algorithms (building on many from VTK) can be linked and executed directly from within a scientific simulation or other applications that need visualization and analysis. We also describe how the ParaView Coprocessing Library can write out partially processed, compressed, or extracted data readable by a traditional visualization application for interactive post-processing. Finally, we will demonstrate the library's scalability in a number of real-world scenarios.

224 citations

Journal ArticleDOI
TL;DR: In this article, single component monolayers of dendrimers and two component monlayers consisting of n-alkanethiols immobilized on Au substrates are described, which are prepared by exposing an Au substrate to ethanolic solutions of amine- or hydroxy-terminated polyamidoamine (PAMAMAM) dielders.
Abstract: Single-component monolayers of dendrimers and two-component monolayers consisting of dendrimers and n-alkanethiols immobilized on Au substrates are described. Single-component monolayers are prepared by exposing an Au substrate to ethanolic solutions of amine- or hydroxy-terminated polyamidoamine (PAMAM) dendrimers. The resulting monolayers are highly stable and nearly close-packed for dendrimer generations ranging from 4 to 8 (G4−G8). Electrochemical ac-impedance measurements indicate that the dendrimer surface is very porous toward the electroactive redox couple Fe(CN)63-/4-. Ferrocene-terminated dendrimer monolayers have also been investigated. Exposure of higher-generation dendrimer monolayers to ethanolic solutions of hexadecanethiol (C16SH) results in a dramatic compression of the dendrimers, and causes them to reorient on the surface from an oblate to prolate configuration. The dendrimers originally present on the surface do not desorb as a consequence of this configurational change. Comparison of ...

224 citations


Authors

Showing all 21652 results

NameH-indexPapersCitations
Lily Yeh Jan16246773655
Jongmin Lee1502257134772
Jun Liu13861677099
Gerbrand Ceder13768276398
Kevin M. Smith114171178470
Henry F. Schaefer111161168695
Thomas Bein10967742800
David Chandler10742452396
Stephen J. Pearton104191358669
Harold G. Craighead10156940357
Edward Ott10166944649
S. Das Sarma10095158803
Richard M. Crooks9741931105
David W. Murray9769943372
Alán Aspuru-Guzik9762844939
Network Information
Related Institutions (5)
Los Alamos National Laboratory
74.6K papers, 2.9M citations

94% related

Argonne National Laboratory
64.3K papers, 2.4M citations

94% related

Oak Ridge National Laboratory
73.7K papers, 2.6M citations

93% related

Georgia Institute of Technology
119K papers, 4.6M citations

93% related

École Polytechnique Fédérale de Lausanne
98.2K papers, 4.3M citations

91% related

Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
202340
2022245
20211,510
20201,580
20191,535
20181,514