EVRI-thing You Need to Know About Volume Fractions in PLS_Toolbox/Solo 9.6

While many calibration data sets for mixtures are given in mass fraction, the spectroscopic method used to measure the samples actually sees volume fractions, i.e. the fractional volume of the sample occupied by each analyte. When the analytes are of different densities this leads to non-linearities between the spectral measurements and mass fractions. Converting to volume fractions solves this and results in improved calibrations.

This webinar was delivered live on  September 17 2026 by Eigenvector President Barry M. Wise.  Barry was joined by Technology Principal Bob Roginski and Senior Developer Lyle Lawrence.  The slides presented by Barry may be accessed here.

Table of Contents

00:00 Welcome & Session Outline
03:08 CLS Model Review & the Volume Fraction Problem
08:58 Demo: Known-Density Example (Hydrocarbon/WW Data)
18:04 Demo: Estimating Unknown Densities (Casein/Glucose/Lactate Data)
26:03 Further Improvement with Gray-CLS
29:56 Volume Fractions in PLS Models & Other Pre-processing Options
40:09 Webinar Schedule & Closing Remarks
41:38 Q&A Session