We present chemical
kinetics measurements of the luminol oxidation
chemiluminescence (CL) reaction at the interface between two aqueous
solutions, using liquid jet technology. Free-flowing liquid microjets
are a relatively recent development that have found their way into
a growing number of applications in spectroscopy and dynamics. A variant
thereof, called flat-jet, is obtained when two cylindrical jets of
a liquid are crossed, leading to a chain of planar leaf-shaped structures
of the flowing liquid. We here show that in the first leaf of this
chain, the fluids do not exhibit turbulent mixing, providing a clean
interface between the liquids from the impinging jets. We also show,
using the example of the luminol CL reaction, how this setup can be
used to obtain kinetics information from friction-less flow and by
circumventing the requirement for rapid mixing by intentionally suppressing
all turbulent mixing and instead relying on diffusion.