Abstract:
A method of correcting for an amplitude change in a spectrometric instrument output includes: exposing a sample in a sample holder to electromagnetic radiation at a plurality of wavenumbers; detecting electromagnetic absorption intensities in the sample at the plurality of wavenumbers; providing to a computer device the detected electromagnetic absorption intensities indexed against wavenumber as spectral data; applying in the computer device a mathematical transform (Icorr) to the spectral data to correct for an amplitude change in the spectrometric instrument's output and calculated by determining a difference (Δ(SBZ)/) between first derivatives of a logarithmic transformation of spectral data (SBZ) from the zero material sample at two different wavenumber ranges (log10(SBZ(x1))/ and log10(SBZ(x2))/); and calculating the mathematical transform (Icorr) as a function inversely dependent on the determined difference (Δ(SBZ)/).
Abstract:
A method of determining a pathlength deviation of a sample (610), the method comprising: exposing the sample (610) to electromagnetic radiation at a plurality of wavenumbers, determining electromagnetic absorption in the sample (610) at the plurality of wavenumbers, determining a first wavenumber associated with a first absorption level of an absorption band and a second wavenumber associated with a second absorption level of the absorption band, wherein the second wavenumber is different from the first wavenumber, determining a difference between the first wavenumber and the second wavenumber, and determining the pathlength deviation based on the difference.
Abstract:
A method of standardizing an output of an electrical property sensor includes calculating a reference magnitude (Condr) of an electrical property of an electrically conductive liquid, based on obtaining, by a spectrometer, spectral data resulting from an interaction of light with the electrically conductive liquid, and applying, in a data processor, a mathematical model to the spectral data to calculate the reference magnitude (Condr) of the electrical property, wherein the mathematical model links the spectral data to magnitudes of the electrical property; comparing, in the data processor, a measured magnitude (Condm) of the electrical property of the electrically conductive liquid with a reference magnitude (Condr) of the electrical property, wherein the measured magnitude (Condm) of the electrical property is obtained with the electrical property sensor; determining, in the data processor, a standardization factor (F) dependent on a ratio of the reference magnitude (Condr) and the measured magnitude (Condm).
Abstract:
A method of determining a constituent related sample property of a multi-constituent sample comprising: subjecting the sample to a perturbation selected to induce a time dependent change in measurement data associated with a constituent related to the sample property to be determined; recording a time-series of measurement data following subjecting the sample to the perturbation; and determining the sample property from the application to the recorded time-series of measurement data of a calibration correlating the sample property with time-series of measurement data, said calibration being empirically derived from chemometric time-series modelling of time-series measurement data recorded for each of a plurality of reference samples following subjecting each reference sample to the perturbation, each reference sample having a different known values of the sample property.