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Title: Tracer counterpermeation analysis of diffusivity in finite-length nanopores with and without single-file dynamics

Abstract

Here, we perform a tracer counterpermeation (TCP) analysis for a stochastic model of diffusive transport through a narrow linear pore where passing of species within the pore is inhibited or even excluded (single-file diffusion). TCP involves differently labeled but otherwise identical particles from two decoupled infinite reservoirs adsorbing into opposite ends of the pore, and desorbing from either end. In addition to transient behavior, we assess steady-state concentration profiles, spatial correlations, particle number fluctuations, and diffusion fluxes through the pore. From the profiles and fluxes, we determine a generalized tracer diffusion coefficient D tr(x), at various positions x within the pore. D tr(x) has a plateau value in the pore center scaling inversely with the pore length, but it is enhanced near the pore openings. The latter feature reflects the effect of fluctuations in adsorption and desorption, and it is also associated with a nontrivial scaling of the concentration profiles near the pore openings.

Authors:
 [1];  [1]
  1. Ames Lab. and Iowa State Univ., Ames, IA (United States)
Publication Date:
Research Org.:
Ames Laboratory (AMES), Ames, IA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1347395
Alternate Identifier(s):
OSTI ID: 1341310
Report Number(s):
IS-J-9128
Journal ID: ISSN 2470-0045; PLEEE8; TRN: US1700958
Grant/Contract Number:
AC02-07CH11358
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review E
Additional Journal Information:
Journal Volume: 95; Journal Issue: 1; Journal ID: ISSN 2470-0045
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Ackerman, David M., and Evans, James W.. Tracer counterpermeation analysis of diffusivity in finite-length nanopores with and without single-file dynamics. United States: N. p., 2017. Web. doi:10.1103/PhysRevE.95.012132.
Ackerman, David M., & Evans, James W.. Tracer counterpermeation analysis of diffusivity in finite-length nanopores with and without single-file dynamics. United States. doi:10.1103/PhysRevE.95.012132.
Ackerman, David M., and Evans, James W.. Thu . "Tracer counterpermeation analysis of diffusivity in finite-length nanopores with and without single-file dynamics". United States. doi:10.1103/PhysRevE.95.012132. https://www.osti.gov/servlets/purl/1347395.
@article{osti_1347395,
title = {Tracer counterpermeation analysis of diffusivity in finite-length nanopores with and without single-file dynamics},
author = {Ackerman, David M. and Evans, James W.},
abstractNote = {Here, we perform a tracer counterpermeation (TCP) analysis for a stochastic model of diffusive transport through a narrow linear pore where passing of species within the pore is inhibited or even excluded (single-file diffusion). TCP involves differently labeled but otherwise identical particles from two decoupled infinite reservoirs adsorbing into opposite ends of the pore, and desorbing from either end. In addition to transient behavior, we assess steady-state concentration profiles, spatial correlations, particle number fluctuations, and diffusion fluxes through the pore. From the profiles and fluxes, we determine a generalized tracer diffusion coefficient Dtr(x), at various positions x within the pore. Dtr(x) has a plateau value in the pore center scaling inversely with the pore length, but it is enhanced near the pore openings. The latter feature reflects the effect of fluctuations in adsorption and desorption, and it is also associated with a nontrivial scaling of the concentration profiles near the pore openings.},
doi = {10.1103/PhysRevE.95.012132},
journal = {Physical Review E},
number = 1,
volume = 95,
place = {United States},
year = {Thu Jan 19 00:00:00 EST 2017},
month = {Thu Jan 19 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
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