Concentration gradients in mixed magnetic and nonmagnetic colloidal suspensions

An approximate analytic model is derived to describe the equilibrium concentration profile within mixed suspensions of magnetic and nonmagnetic colloidal particles, and a strong qualitative agreement is shown between theory and experiment. This work extends previous theoretical and experimental investigations of density profiles within magnetic nanoparticle fluids, known as ferrofluid. (c) 2008 American Institute of Physics.