DOI:, To celebrate 50 years of enduring discoveries, APS is offering 50% off APCs for any manuscript submitted in 2020, published in any of its hybrid journals: PRL, PRA, PRB, PRC, PRD, PRE, PRApplied, PRFluids, and PRMaterials. To address this, we have been improving access via several different mechanisms. And we hope you, and your loved ones, are staying safe and healthy. Its applications range from transportinamorphousandporousmediaandcompositesto thepropertiesofbranched polymers, gels and complex ionic conductors. Learn More »., Physical Review Physics Education Research, Log in with individual APS Journal Account », Log in with a username/password provided by your institution », Get access through a U.S. public or high school library ». Representative elementary volume analysis was performed to determine the suitable size of the digital sample. The. See Off-Campus Access to Physical Review for further instructions. According to the percolation theory, the relationship between the conductivity and the volume fraction of the composite filler is given by [45] (5.65) σ = σ 0 ( V f − V c ) … The interconnection and transport properties of the carbon nanotube (CNT) network in the porous composite were investigated with the proposed scheme. conductanceG(x),normalized sothat G(1)=1,is plotted as a function of the bond fraction,p. Rev. ScienceDirect ® is a registered trademark of Elsevier B.V. ScienceDirect ® is a registered trademark of Elsevier B.V. Percolation and conductivity development of the rod networks within randomly packed porous media. We report the results of an experiment to determine the bulk conductivity of a sheet of colloidal graphite paper with holes randomly punched in it. Last and D. J. Thouless Phys. Physical Review Letters™ is a trademark of the American Physical Society, registered in the United States, Canada, European Union, and Japan. A percolation-permeation-diffusion simulation and analysis scheme was proposed with Cellular Automata (CA) and Lattice Boltzmann method (LBM). Hydration product covering CNT magnify the elementary resistivity to tens times. The proposed simulation-analysis scheme is a generic method to evaluate the conductive network formed in porous media. Subscription ©2020 American Physical Society. Percolation is a standard model for disordered systems. A general trend that increased network content increased the electrical conductivity was observed both numerically and experimentally. All rights reserved. Because of universality the results do not depend on the specific model, and general scaling laws can be deduced. The physical system was modelled as the rod-particle composite with an adjustable packing density of the porous medium, and experiment on the electrical resistivity development was conducted on the CNT-cement composite. We appreciate your continued effort and commitment to helping advance science, and allowing us to publish the best physics journals in the world. Many researchers now find themselves working away from their institutions and, thus, may have trouble accessing the Physical Review journals. Percolation Theory and Electrical Conductivity B. J. The APS Physics logo and Physics logo are trademarks of the American Physical Society. © 2020 Elsevier Ltd. All rights reserved. Conditions and any applicable We use cookies to help provide and enhance our service and tailor content and ads. The percolation threshold is reached when the insulator - conductor transition is observed. The behavior of the conductivity is found to be quite different from that of the percolation probability. The percolation threshold for the GA/epoxy composites was found to be ~0.25 wt.%, with the highest conductivity of 20 S m −1 obtained at 1.4 wt.% graphene content, which is 4 orders of magnitude higher than that found for 2.0 wt.% GNP , and nearly 2 orders of magnitude higher than those containing 3 wt.% CRGO or 1 wt.% CNTs . 27, 1719 – Published 20 December 1971 Copyright © 2020 Elsevier B.V. or its licensors or contributors. Densely packed porous medium enhances the conductivity of the network within. Download : Download high-res image (636KB)Download : Download full-size image.