QUANTITATIVE MAPPING OF SPECIES MOVING IN SOLUTION BY X-RAY PROJECTION MICROSCOPY

An x-ray projection microscope equipped with a digital camera allows a rapid and independent mapping of copper and iron ions in an aqueous s ulphate solution during the corrosion/deposition process of a metallic iron electrode in a copper sulphate solution. The concentration distr ibutions of the two species can be quantified from a pair of x-ray ima ges acquired in 20 s with a resolution on the order of 10 mu m. Four p airs of images have been acquired each minute of the corrosion deposit ion process. This technique makes it possible to follow the concentrat ion distribution of the two species as a function of the space (x,y) a nd time coordinates with a detection limit in the 10 ppm range. (C) 19 97 American Institute of Physics.