Institution
National Institute of Standards and Technology
Government•Gaithersburg, Maryland, United States•
About: National Institute of Standards and Technology is a government organization based out in Gaithersburg, Maryland, United States. It is known for research contribution in the topics: Laser & Scattering. The organization has 26667 authors who have published 60661 publications receiving 2215547 citations. The organization is also known as: National Bureau of Standards & NIST.
Topics: Laser, Scattering, Neutron scattering, NIST, Spectroscopy
Papers published on a yearly basis
Papers
More filters
••
TL;DR: In this paper, phase diagram data in the Sn-Ag-Cu system were measured and the location of the ternary eutectic involving L, (Sn), Ag3Sn and Cu6Sn5 phases was confirmed to be at a composition of 3.5 wt.% Ag, 0.91 wt% Cu at a temperature of 216.2±0.3°C.
Abstract: Sn-rich alloys in the Sn-Ag-Cu system are being studied for their potential as Pb-free solders. Thus, the location of the ternary eutectic involving L, (Sn), Ag3Sn and Cu6Sn5 phases is of critical interest. Phase diagram data in the Sn-rich corner of the Sn-Ag-Cu system are measured. The ternary eutectic is confirmed to be at a composition of 3.5 wt.% Ag, 0.9 wt.% Cu at a temperature of 217.2±0.2°C (2σ). A thermodynamic calculation of the Sn-rich part of the diagram from the three constituent binary systems and the available ternary data using the CALPHAD method is conducted. The best fit to the experimental data is 3.66 wt.% Ag and 0.91 wt.% Cu at a temperature of 216.3°C. Using the thermodynamic description to obtain the enthalpy- temperature relation, the DTA signal is simulated and used to explain the difficulty of liquidus measurements in these alloys.
530 citations
••
TL;DR: In this paper, the influence of lattice element type and lattice orientation on the fracture pattern was investigated by simulating a shear loading experiment on a concrete plate, and the effect of element resolution on fracture results was also investigated.
529 citations
••
TL;DR: Current-voltage measurements of metal-molecule-metal junctions formed from pi-conjugated thiols exhibit an inflection point on a plot of ln(I/V(2)) vs 1/V, consistent with a change in transport mechanism from direct tunneling to field emission.
Abstract: Current-voltage measurements of metal-molecule-metal junctions formed from pi-conjugated thiols exhibit an inflection point on a plot of ln(I/V(2)) vs 1/V, consistent with a change in transport mechanism from direct tunneling to field emission. The transition voltage was found to scale linearly with the offset in energy between the Au Fermi level and the highest occupied molecular orbital as determined by ultraviolet photoelectron spectroscopy. Asymmetric voltage drops at the two metal-molecule interfaces cause the transition voltage to be dependent on bias polarity.
529 citations
••
Sandia National Laboratories1, University of Pittsburgh2, Georgia Institute of Technology3, Pennsylvania State University4, University of Maryland, College Park5, National Institute of Standards and Technology6, Los Alamos National Laboratory7, Zhejiang University8, Massachusetts Institute of Technology9
TL;DR: It is shown that in situ transmission electron microscopy can be used to study the dynamic lithiation process of single-crystal silicon with atomic resolution and observe a sharp interface between the crystalline silicon and an amorphous Li(x)Si alloy.
Abstract: In lithium-ion batteries, the electrochemical reaction between the electrodes and lithium is a critical process that controls the capacity, cyclability and reliability of the battery. Despite intensive study, the atomistic mechanism of the electrochemical reactions occurring in these solid-state electrodes remains unclear. Here, we show that in situ transmission electron microscopy can be used to study the dynamic lithiation process of single-crystal silicon with atomic resolution. We observe a sharp interface (~1 nm thick) between the crystalline silicon and an amorphous Li(x)Si alloy. The lithiation kinetics are controlled by the migration of the interface, which occurs through a ledge mechanism involving the lateral movement of ledges on the close-packed {111} atomic planes. Such ledge flow processes produce the amorphous Li(x)Si alloy through layer-by-layer peeling of the {111} atomic facets, resulting in the orientation-dependent mobility of the interfaces.
529 citations
••
TL;DR: In this paper, the temperature-dependent Raman spectra of exfoliated, monolayer molybdenum disulfide (MoS2) in the range of 100-320 K were analyzed.
Abstract: Atomically thin molybdenum disulfide (MoS2) offers potential for advanced devices and an alternative to graphene due to its unique electronic and optical properties. The temperature-dependent Raman spectra of exfoliated, monolayer MoS2 in the range of 100–320 K are reported and analyzed. The linear temperature coefficients of the in-plane E2g1 and the out-of-plane A1g modes for both suspended and substrate-supported monolayer MoS2 are measured. These data, when combined with the first-order coefficients from laser power-dependent studies, enable the thermal conductivity to be extracted. The resulting thermal conductivity κ = (34.5 ± 4) W/mK at room temperature agrees well with the first-principles lattice dynamics simulations. However, this value is significantly lower than that of graphene. The results from this work provide important input for the design of MoS2-based devices where thermal management is critical.
528 citations
Authors
Showing all 26760 results
Name | H-index | Papers | Citations |
---|---|---|---|
Zhong Lin Wang | 245 | 2529 | 259003 |
John A. Rogers | 177 | 1341 | 127390 |
J. N. Butler | 172 | 2525 | 175561 |
Yury Gogotsi | 171 | 956 | 144520 |
Zhenan Bao | 169 | 865 | 106571 |
Gang Chen | 167 | 3372 | 149819 |
Michel C. Nussenzweig | 165 | 516 | 87665 |
Donald G. Truhlar | 165 | 1518 | 157965 |
Tobin J. Marks | 159 | 1621 | 111604 |
Jongmin Lee | 150 | 2257 | 134772 |
Galen D. Stucky | 144 | 958 | 101796 |
Thomas P. Russell | 141 | 1012 | 80055 |
William D. Travis | 137 | 605 | 93286 |
Peter Zoller | 134 | 734 | 76093 |
Anthony G. Evans | 130 | 576 | 65803 |