Basis For Diffusion Research Articles

Correction to “The physical basis for anomalous diffusion in bed load transport”

[1] In the paper “The physical basis for anomalous diffusion in bed load transport” by Raleigh L. Martin et al. (Journal of Geophysical Research, 117, F01018, doi:10.1029/ 2011JF002075, 2012) paragraph 5 should read as follows. Nikora et al. [2002] suggested that the character of anomalous sediment diffusion may change with time scale. In their conceptual model, superdiffusion at short time scales (“local regime”) resulted from correlated particle motions arising from particle inertia, and subdiffusion at long time scales (“global regime”) resulted from periods of particle immobility (wait times) with a heavy tail. (In contrast, Bradley et al. [2010] observed superdiffusion in the global regime.) Over medium time scales (“intermediate regime”), Nikora et al. [2002] also observed superdiffusion, but suggested that the type of diffusion in this regime may depend on system properties.

Cellular Automata Models of the Influences on Solute Diffusion through Water

A cellular automata (CA) model of liquid water has been used to study self-diffusion and the diffusion of a solute. The influences of temperature and solute hydropathic state are modeled as variables in this process. The self-diffusion model correlates very well with earlier experimental data. The diffusion of a solute experiences variation with temperature and its hydropathic states. These influences are found to relate to models of free hydroxy groups and the average cavity cluster size in bulk water. These preliminary models serve as the basis for modeling solute diffusion for specific contaminants of interest (such as heavy metals like uranium) in a water system, and addressing its migration patterns with water relative to temperature.