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Displaying 101 - 125 of 638

Ion transport across solid-state ion channels perturbed by directed strain

April 28, 2020
Author(s)
Alex Smolyanitsky, Alta Y. Fang, Andrei F. Kazakov, Eugene Paulechka
We combine quantum-chemical calculations and molecular dynamics simulations to consider aqueous ion flow across non-axisymmetric nanopores in monolayer graphene and MoS2. When the pore-containing membrane is subject to uniaxial tensile strains applied in

Uncertainty analysis of adsorption measurements using commercial gravimetric sorption analyzers with simultaneous density measurement based on a magnetic-suspension balance

April 27, 2020
Author(s)
Xiaoxian Yang, Reiner Kleinrahm, Mark O. McLinden, Markus Richter
A commercial gravimetric sorption analyzer, which is based on a magnetic-suspension balance, was significantly improved to reduce the uncertainty in adsorption measurements. In a previous paper, we investigated the force-transmission error (FTE) of the

Flat-Histogram Extrapolation as a Useful Tool in the Age of Big Data

April 13, 2020
Author(s)
Nathan Mahynski, Harold Hatch, Matthew Witman, David Sheen, Jeffrey R. Errington, Vincent K. Shen
Here we review recent work by the authors to revisit the concept of extrapolating thermodynamic properties of classical systems using statistical mechanical principles. Specifically, we discuss how the combination of these principles with biased sampling

An Entropy Scaling Demarcation of Gas- and Liquid-like Fluid Behaviors

April 1, 2020
Author(s)
Ian H. Bell, Guillaume Galliero, Stephanie Delage-Santacreu, Lorenzo Costigliola
In this work we propose a generic and simple definition of a line separating gas-like and liquid-like fluid behaviors in the supercritical region. We argue that this line is defined by the location of the minimum of the macroscopically scaled viscosity

Grand Canonical Inverse Design of Multicomponent Colloidal Crystals

February 19, 2020
Author(s)
Nathan Mahynski, Evan Pretti, Runfang Mao, Vincent K. Shen, Jeetain Mittal
Inverse design methods are powerful computational approaches for creating colloidal systems which self-assemble into a target morphology by reverse engineering the Hamiltonian of the system. Despite this, these optimization procedures tend to yield

Options for Low-GWP Refrigerants

November 6, 2019
Author(s)
Mark O. McLinden, Andrei F. Kazakov, J S. Brown, Riccardo Brignoli, Ian H. Bell, Piotr A. Domanski
We summarize a systematic examination of possible low-GWP (global warming potential) replacements for the HFC (hydrofluorocarbon) refrigerants currently used in small air-conditioning systems. The methodology identified the optimal thermodynamic parameters

Measurements and Modeling Thermophysical Properties of Lubricants

September 24, 2019
Author(s)
Marcia L. Huber
Slides for presentation at SAE E-34 Propulsion Lubricants Committee meeting that discuss project comprised of measurements and modeling to provide thermophysical properties of a lubricant that meets military specification MIL-PRF-23699

110th Anniversary: Properties of Imidazolium-based Ionic Liquids Bearing both Benzylic and n-Alkyl Substituents

September 4, 2019
Author(s)
Joe W. Magee, Shuai Qian, Kathryn E. O'Harra, Grayson P. Dennis, Richard D. Noble, Jason E. Bara, Alexia Finotello
Reports of imidazolium-based ionic liquids (ILs) with at least one benzylic substituent bound to the imidazolium cation is far less common than the ubiquitous 1-alkyl-3-methylimidazolium ILs ([Cnmim][X]). Yet, there is significant motivation to determining

Thermodynamics of the New Refrigerants

August 24, 2019
Author(s)
Mark O. McLinden
As the refrigeration industry moves towards low-GWP refrigerants the number of acceptable refrigerants is decreasing due to new environmental constraints, but, at the same time, a variety of new options are becoming available. These "new" refrigerants

A semiclassical theory of phase-space dynamics of interacting bosons

August 21, 2019
Author(s)
Eite Tiesinga, Ranchu Mathew
We study the phase-space representation of dynamics of bosons in the semiclassical regime where the occupation number of the modes is large. To this end, we employ the van Vleck-Gutzwiller propagator to obtain an approximation for the Green’s function of

Liquid Viscosity and Surface Tension of n-Hexane, n-Octane, n-Decane, and n-Hexadecane up to 573 K by Surface Light Scattering (SLS)

August 16, 2019
Author(s)
Tobias Klein, Shaomin Yan, Junwei Cui, Joe W. Magee, Kenneth Kroenlein, Michael H. Rausch, Thomas M. Koller, Andreas P. Froba
In the present study, the simultaneous and accurate determination of liquid viscosity and surface tension of the n-alkanes n-hexane (n-C6H14), n-octane (n-C8H18), n-decane (n-C10H22), and n-hexadecane (n-C16H34) by surface light scattering (SLS) in

The role of molecular modeling & simulation in the discovery and deployment of metal-organic frameworks for gas storage and separation

August 8, 2019
Author(s)
Arni Sturluson, Melanie Huynh, Alec Kaija, Caleb Laird, Sunghyun Yoon, Feier Hou, Zhenxing Feng, Christopher E. Wilmer, Yamil J. Colon, Yongchul G. Chung, Daniel Siderius, Cory M. Simon
Metal-organic frameworks (MOFs) are highly tunable, extended-network, crystalline, nanoporous materials with applications in gas storage, separations, and sensing. We review how molecular models and simulations of gas adsorption in MOFs have lucidly

Molecular Calculation of the Critical Parameters of Classical Helium

July 2, 2019
Author(s)
Richard A. Messerly, Navneeth Gokul, Andrew J. Schultz, David A. Kofke, Allan H. Harvey
We compute the vapor-liquid critical coordinates of a model of helium in which nuclear quantum effects are absent. We employ highly accurate ab initio pair and three-body potentials and calculate the critical parameters rigorously in two ways. First, we

Modified Entropy Scaling of the Transport Properties of the Lennard-Jones Fluid

June 26, 2019
Author(s)
Ian H. Bell, Richard A. Messerly, Monika Thol, Lorenzo Costigliola, Jeppe Dyre
Separated by twenty-two years, Rosenfeld proposed two different scaling approaches to model the transport properties of fluids, one valid in the dilute gas, and another in the liquid phase. In this work, we demonstrate that these two limiting cases can be

VISCOSITY OF GASES

June 7, 2019
Author(s)
Marcia L. Huber
This is a chapter in CRC that contains tables with viscosity of gases
Displaying 101 - 125 of 638