In situ Raman imaging of interdiffusion in a microchannel -: art. no. 094106

This letter presents an experimental setup to probe the interdiffusion of various miscible and nonreacting liquids. A Raman confocal microscope allows us to image the local concentrations of two coflowing liquids in a microchannel. These steady-state measurements provide precise quantitative information about the kinetics of the interdiffusion process. For all the pairs of fluids investigated, we found this process to follow a classical diffusive scaling law with a interdiffusion coefficient D that depends on both liquids. (C) 2005 American Institute of Physics.