convex isotherm

in chromatography
Distribution isotherm, the slope of which is continuously decreasing.
Note:
The resulting chromatographic peak is tailing. Adsorption isotherms are often of this type. A special case is the Langmuir adsorption isotherm.
Source:
PAC, 1996, 68, 1591 (Nomenclature for non-linear chromatography (IUPAC Recommendations 1996)) on page 1593