Fig. 6

(a) Correlation analysis of first-order differentials with raw spectra; (b) Correlation analysis of second-order differentials with raw spectra; (c) Correlation analysis of SG smoothing with raw spectra.
(a) Correlation analysis of first-order differentials with raw spectra; (b) Correlation analysis of second-order differentials with raw spectra; (c) Correlation analysis of SG smoothing with raw spectra.