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Abstract
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Continuous wavelet transform together with
zero-crossing technique was applied to the overlapping
visible spectra, as a very simple and accurate method, for
the simultaneous determination of phosphate and silicate
without any prior separation steps. Daubechies-4, Symlet 8,
and Meyer continuous wavelet transforms for signal
treatments were found to be suitable. The calibration
graphs for estimation of complexes were obtained by
measuring the wavelet coefficients at zero-crossing points
for silicomolybdenum blue and phosphomolybdenum blue.
The constructed calibration functions were tested by analyzing the composition of the different binary mixtures.
The experimental data were also analyzed using partial
least squares and first-order derivative spectrophotometric
method. The proposed method was validated by simultaneous determination of phosphate and silicate in different
environmental waters and soil samples. The results of
proposed method have been compared with those predicted
by partial least squares and standard methods.
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