Tests of Flowing Junction Diffusion Cells with Interference Methods

The construction and manipulation of two diffusion cells, one of glass and the other of stainless steel, are described. In both cells the initially sharp boundary is formed by allowing solution and solvent to flow together into a narrow horizontal exit slit in the side wall of the diffusion channel. These cells have been tested by diffusion measurements with the aid of the Gouy interference method. Moreover, in the case of the metal cell which is provided with a reference channel in close proximity to that in which diffusion occurs, an interference method that gives the refractive index directly as a function of the height has also been studied.