Equilibrium Measurements of the NH₃-CO₂-H₂O System: Speciation Based on Raman Spectroscopy and Multivariate Modeling

Figure 2

Preprocessing steps of the calibration and validation Raman spectra of bicarbonate. (a) Raw spectra for the range of 100–3325 cm⁻¹. (b) Spectra cropped to cover the range of 450–2300 cm⁻¹. (c) Spectra baseline corrected using the Whittaker filter (lambda = 100; ). (d) Mean-centered spectra for PLS-R model calibration.

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