English
Related papers

Related papers: Anomalous diffusion coefficient in disordered medi…

200 papers

Fractional kinetic equations employ non-integer calculus to model anomalous relaxation and diffusion in many systems. While this approach is well explored, it so far failed to describe an important class of transport in disordered systems.…

Statistical Mechanics · Physics 2021-01-04 Wanli Wang , Eli Barkai

In this paper, we present a numerical solution to an ordinary differential equation of a fractional order in one-dimensional space. The solution to this equation can describe a steady state of the process of anomalous diffusion. The process…

Numerical Analysis · Mathematics 2014-12-03 Mariusz Ciesielski , Jacek Leszczynski

Fluctuations affect nanoporous transport in complex and intricate ways, making optimization of signal-to-noise in artificial designs challenging. Here we focus on the simplest nanopore system, where non-interacting particles diffuse through…

Soft Condensed Matter · Physics 2021-05-19 Sophie Marbach

Diffusion pore imaging is an extension of diffusion-weighted nuclear magnetic resonance imaging enabling the direct measurement of the shape of arbitrarily formed, closed pores by probing diffusion restrictions using the motion of…

We present new simulation results on a hard sphere system at high densities. Using three-time correlations, we can account for the anomalous diffusion, which results from a homogeneous back-dragging effect. Furthermore, we calculate the…

Soft Condensed Matter · Physics 2007-05-23 Burkhard Doliwa , Andreas Heuer

In this work we show that under specific anomalous diffusion conditions, chemical systems can produce well-ordered self-similar concentration patterns through a diffusion-driven instability. We also find spiral patterns and patterns with…

Pattern Formation and Solitons · Physics 2017-02-22 D. Hernández , E. C. Herrera-Hernández , M. Núñez-López , H. Hernández-Coronado

Fractional Brownian motion (FBM), a non-Markovian self-similar Gaussian stochastic process with long-ranged correlations, represents a widely applied, paradigmatic mathematical model of anomalous diffusion. We report the results of…

This paper is devoted to the anomalous diffusion limit of kinetic equations with a fractional Fokker-Planck collision operator in a spatially bounded domain. We consider two boundary conditions at the kinetic scale: absorption and specular…

Analysis of PDEs · Mathematics 2017-11-10 Ludovic Cesbron

Restrictions to diffusion result in the dispersion of the bulk diffusion coefficient. We derive the exact universal high-frequency behavior of the diffusion coefficient in terms of the surface-to-volume ratio of the restrictions. This…

Soft Condensed Matter · Physics 2011-03-11 Dmitry S. Novikov , Valerij G. Kiselev

We present a numerical study of classical particles diffusing on a solid surface. The particles' motion is modeled by an underdamped Langevin equation with ordinary thermal noise. The particle-surface interaction is described by a periodic…

Statistical Mechanics · Physics 2009-11-10 J. M. Sancho , A. M. Lacasta , K. Lindenberg , I. M. Sokolov , A. H. Romero

Diffusion processes are important in several physical, chemical, biological and human phenomena. Examples include molecular encounters in reactions, cellular signalling, the foraging of animals, the spread of diseases, as well as trends in…

Data Analysis, Statistics and Probability · Physics 2021-06-21 Alessia Gentili , Giorgio Volpe

In this work we study analytically and numerically the transport properties of non-interacting active particles moving on a $d$-dimensional disordered media. The disorder in the space is modeled by means of a set of non-overlapping…

Statistical Mechanics · Physics 2022-07-20 R. Salgado-García

We study the influence of diffusion on NMR experiments when the molecules undergo random motion under the influence of a force field, and place special emphasis on parabolic (Hookean) potentials. To this end, the problem is studied using…

Medical Physics · Physics 2016-05-11 Cem Yolcu , Muhammet Memiç , Kadir Şimşek , Carl-Fredrik Westin , Evren Özarslan

Mass transport problems are ubiquitous in diverse fields of physics and engineering. With the development of fractional calculus, many have taken to studying problems of fractional mass transport either through numerical simulations or…

Mathematical Physics · Physics 2025-06-18 Nathaniel G. Hermann , M. Shane Hutson

The diffusion of atoms and radicals on interstellar dust grains is a fundamental ingredient for predicting accurate molecular abundances in astronomical environments. Quantitative values of diffusivity and diffusion barriers usually rely…

Astrophysics of Galaxies · Physics 2021-12-22 Viktor Zaverkin , Germán Molpeceres , Johannes Kästner

The purpose of this tutorial is to introduce the main concepts behind normal and anomalous diffusion. Starting from simple, but well known experiments, a series of mathematical modeling tools are introduced, and the relation between them is…

Chaotic Dynamics · Physics 2008-05-06 Loukas Vlahos , Heinz Isliker , Yannis Kominis , Kyriakos Hizanidis

The Larmor frequency shift is found in porous media consisting of NMR-reporting fluid filling a connected pore within an NMR-invisible matrix for the case of fast diffusion in the fluid. The matrix material has a distinct…

Soft Condensed Matter · Physics 2019-02-20 Valerij G. Kiselev

We present a model of anomalous diffusion consisting of an ensemble of particles undergoing homogeneous Brownian motion except for confinement by randomly placed reflecting boundaries. For power-law distributed compartment sizes, we…

Soft Condensed Matter · Physics 2015-06-09 Gerald John Lapeyre

Countless systems in biology, physics, and finance undergo diffusive dynamics. Many of these systems, including biomolecules inside cells, active matter systems and foraging animals, exhibit anomalous dynamics where the growth of the mean…

Statistical Mechanics · Physics 2021-08-11 Aykut Argun , Giovanni Volpe , Stefano Bo

We provide a numerical algorithm for the model characterizing anomalous diffusion in expanding media, which is derived in [F. Le Vot, E. Abad, and S. B. Yuste, Phys. Rev. E {\bf96} (2017) 032117]. The Sobolev regularity for the equation is…

Numerical Analysis · Mathematics 2020-11-13 Daxin Nie , Jing Sun , Weihua Deng
‹ Prev 1 4 5 6 7 8 10 Next ›