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Showing 1 to 20 of 34 for “"percolation threshold"”.
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Computational Prediction of Conductivities of Disk-Shaped Particulate Composites
… the computational effort in search of the percolation paths. The estimated percolation threshold agrees well with the result reported in the literature. It has been confirmed that the statistical invariant for percolation is a cubic function of the characteristic size, and that the …
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Percolation behavior of diffusionally evolved two-phase systems simulated using phase field methods
Percolation is an important phenomenon that dramatically affects the properties of many multi-phase materials. As such, significant prior work has been done to investigate the percolation threshold and critical scaling exponents of randomly assembled composites. However many materials are …
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Microstructural modeling of lithium battery electrodes
… of view. Electron transport was analyzed using percolation theory and comparison with other conductor-insulator composites. An in situ filter pressing apparatus was designed and constructed in order to determine the percolation threshold in composite electrode systems. In addition, the effect of …
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Monte Carlo computer simulation of sub-critical Lennard-Jones particles
… Metropolis Monte Carlo computer simulations. The percolation probability and cluster distribution is calculated for several state points in the gas-liquid equilibrium region of the LJ fluid. The cluster number distribution is used to analyze the distribution of clusters above and below the …
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Synthesis, Characterisation and Device Application of Silicon Nanoparticles produced by Mechanical Attrition
… The nanocomposite systems show a clear percolation threshold for charge conduction. Below the percolation threshold, transport is mainly limited by the matrix or insulating binding medium. Direct tunneling and eld emission (FE) are the major transport mechanism for all concentrations at …
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Percolation and homogenization theories for heterogeneous materials
… of connectivity can be effectively captured by a percolation threshold, a case-specific volume fraction at which the macroscopic effective property undergoes a critical transition, and a set of critical scaling exponents, which also reflect the universality class that the property belongs to. …
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Development of semi-solid alkaline flow battery
… of the large particles. Secondly, we determined percolation threshold of conductive additive and investigated its effect on electrochemical performance of the semi-solid electrodes in a closed static cell. We found that conductive additive concentration should be well above percolation threshold …
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A Percolation Model for Boiling and Predicting CHF
… A recently investigated way to model CHF uses percolation theory, which states that CHF is reached at the percolation threshold. A bubble percolation model is used to visualize and predict boiling performance. The predictions of these models will then be used for characterizing the boiling …
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Mechanical and electrical characterization of carbon Black-doped closed-cell Polydimethylsiloxane (PDMS) foam
… and other hydrodynamic sensing purposes. The percolation threshold for conduction through the CB-PDMS foam is theorized, and a number of different concentrations based on the theorized threshold are explored in order to determine the optimum weight percent of Carbon Black dopant to achieve a …
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Percolation in Two-Dimensional Grain Boundary Structures and Polycrystal Property Closures
… by the microstructure. The first topic involves percolation as a tool in relating the grain boundary structure to global properties such as fracture and corrosion resistance. The second investigates optimization techniques in order to find the space of values that properties of a material can …
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Transport properties of graphite-loaded composites in liquid and solid states
… conductivity increases more rapidly below the percolation threshold than above it, with a sharp kink at the percolation. Our study suggests that the below the percolation, the aggregation of graphite flakes is tighter and interfacial resistance is smaller, while above the percolation threshold, …
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The first high-strength bainitic steel designed for hydrogen embrittlement resistance
… volume fraction of retained austenite above its percolation threshold, theorised as 0.1, which was proven to form an effcient barrier to hydrogen ingress. The effective diffusivity of hydrogen, measured using an electrochemical permeation technique, was shown to decrease with increasing austenite …
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In-situ production of electrically conductive polyaniline fibres from polymer blends
… be characteristic of a percolating system with a threshold as low as 5 weight percent of the conducting filler in the blends. The morphological analysis performed on the extruded blends suggested that the conducting phase was deformed into elongated domains, aligned parallel to the extrusion …
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Dynamic electromechanical measurements of carbon black loaded SBR
… carbon black loadings below, at, and above the percolation threshold. Characteristics of dielectric dispersion depend strongly on carbon black loading and frequency. Dielectric and AC conductivity measurements are shown to provide a nondestructive method to explore the carbon black network …
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Caging and Transport in Simple Disordered Systems
… transport. In particular, seemingly incompatible percolation and mean-field caging descriptions on the localization transition call for better understanding both. In light of this fundamental inconsistency, we study the caging and transport of a series of simple disordered systems.</p><p>We first …
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Analytical and Experimental Investigation of Interphase and Dispersion Effects on the Mechanical Stiffness of Cellulose Nanocomposites
… predictions, the possibility of a secondary percolation threshold due to high interphase volume merits further investigation. Due to these results, the enhanced stiffness seen for PD-CNC-SPI films relative to unmodifed CNC-SPI films was attributed to improved dispersion through increased …
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Feasibility study on producing functional parts using molding technology
… resistivity decreases with the arising of percolation thresholds. The key parameter in this case is the packing factor F which equal to 0.46, represents the maximum point of percolation threshold that achieve conductive composite.
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Synthesis and characterization of ultra violet curable renewable polymer graphite composites
… properties in which the composites achieved percolation threshold at RPG20 composites. Moreover, the decreased in optical energy band gap (Eg) which afterwards took the leads to electrical conductivity (σ). Aptly, the composites (RPG20, RPG25 and RPG30) were found to possess favorable …
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Computational Studies on the Effective Properties of Two-Phase Heterogeneous Media
… ellipsoidal particles.</p> <p>The geometric percolation thresholds for circular, elliptical, square and triangular disks in the three-dimensional space are determined precisely by Monte Carlo simulations. These geometries represent oblate particles in the limit of zero thickness. The …
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Free-radical maleation of poly(butylene adipate-co-terephthalate) in supercritical carbon dioxide and its effect on the percolation and deformation mechanism of layered silicate nanocomposites
… response under oscillatory shear, and a percolation threshold was determined to occur at 3.88% clay by weight. Transmission electron microscopy (TEM), x-ray diffraction (XRD), and the water vapor transmission rate (WVTR) were also utilized to elucidate the clay nanoparticle structure and …
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