9.1.   Methanol and Ethanol by SPR

Measurements of the two homologues Methanol and Ethanol allow investigations of the difference of the kinetics of sorption and desorption, which is mainly based on the different sizes of the two analytes. Therefore several measurements of single analytes and measurements of mixtures were performed, which are described in section 4.5.2.1 and in [190] in detail. Besides of non-optimized neural networks, the parallel growing neural network framework is applied to the data resulting in a very small number of variables being selected. This small number of variables allows the insight into the "black box" of the calibration by neural networks by the use of a sensitivity analysis. Additionally, the selection of the variables is confirmed by a brute-force variable selection.