We study an aggregation-disaggregation model which is relevant to biological processes such as the growth of senile plaques in Alzheimer disease. In this model, during the aggregation each deposited particle has a probability of producing a new particle in its vicinity, while during disaggregation the particles are anihilated randomly. The model is held in a dynamic equilibrium by a feedback me...

Recent advances in understanding of magnetohydrodynamic (MHD) turbulence call for revisions in the picture of particle acceleration. We make use of the recently established scaling of slow and fast MHD modes in strong and weak MHD turbulence to provide a systematic study of particle acceleration in magnetic pressure (low-β) and gaseous pressure (high-β) dominated plasmas. We consider the accele...

CO2 is the main greenhouse gas which causes global climatic changes on larger scale. Many techniques have been utilised to capture CO2. Membrane gas separation is a fast growing CO2 capture technique, particularly gas separation by composite membranes. The separation of CO2 by a membrane is not just a process to physically sieve out of CO2 through the controlled membrane pore size. It mainly de...

We report sorption isotherms and uptake kinetics for phenanthrene and pyrene with three organic model sorbents: polyoxymethylene (POM), coke, and activated carbon. We combine batch equilibration and kinetic experiments with the direct observation of the long-term diffusion of phenanthrene and pyrene as measured within cross-sectioned particles using microprobe laser-desorption laser-ionization ...

In this study, we presented the high-order fundamental solutions and general solutions of convection-diffusion equation. To demonstrate their efficacy, we applied the highorder general solutions to the boundary particle method (BPM) for the solution of some inhomogeneous convection-diffusion problems, where the BPM is a new truly boundaryonly meshfree collocation method based on multiple recipr...

We consider many-particle diffusion in 2D colloidal suspensions with hydrodynamic interactions within a mode-coupling approach. We focus on the behaviour of the effective scaled collective diffusion coefficient DC(ρ)/D0 as a function of the density of the colloids ρ, where D0 is the single-particle diffusion coefficient. We find that DC(ρ) is strongly coupled to hydrodynamical conservation laws...

We investigate the diffusion of a colloidal particle in a tilted periodic potential created by means of ten rotating optical tweezers arranged on a circle. Because of the viscous drag, the trap rotation leads to the onset of a tilting force in the corotating reference frame, so that in that frame the system can be described as an overdamped Brownian particle in a tilted periodic potential. The ...

The diffusive motion of a colloidal particle trapped inside a small cavity filled with fluid is reduced by hydrodynamic interactions with the confining walls. In this work, we study these wall effects on a spherical particle entrapped in a closed cylinder. We calculate the diffusion coefficient along the radial, azimuthal, and axial direction for different particle positions. At all locations t...

The effects of immobilizing a thin layer of water adjacent to the surface of a colloidal particle are calculated using the Dynamic Stern Layer model introduced by Zukoski and Saville. Supposing water is immobilized by, for example, unreacted monomer or polymer chains dangling from the particle surface allows one to divide the diffuse layer into two regions, an outer region where transport is by...

The properties of one-particle and particle-pair diffusion in rotating and stratified turbulence are studied by applying the rapid distortion theory to a kinematic simulation of the Boussinesq equation with a Coriolis term. We discuss the simplified Corrsin hypothesis and restrict the validity of its predictions to pure rotation. We emphasize the existence of two tau regimes driven by very diff...