Simultaneous spectrophotometric determination of phosphate and silicate in different water and soil samples using chemometrics approach

Abstract

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.

Mean Centered Kinetic—Spectrophotometric Data—Continuous Wavelet Transform for Simultaneous Determination of Dopamine and Uric Acid in Presence of Ascorbic Acid at Biological Samples

“…WT is very effective for eliminating or reducing of baseline effect and noise of data, data compression, recognition and detection of latent transient information [24,28]. The combination of continuous wavelet transforms (CWT) and zero crossing technique has been adjusted for the simultaneous determination of different binary and ternary mixtures [29][30][31][32][33][34][35].…”

Nitrogen-modified nanoporous activated carbon from eucalyptus leaves for ultrasound-assisted removal of basic dyes using derivative spectrophotometric method

“…The derivatization of the zero order spectrum can lead to the separation of overlapped signals and to the elimination of background caused by the presence of the other compounds in a sample. 2,15 In this study, a low-cost nanoporous activated carbon with a large surface area was prepared from eucalyptus leaves through KOH activation, then treated with nitric acid and urea (NOAC) and finally used as a new nanoadsorbent for the simultaneous ultrasound-assisted removal of basic red 46 (BR46) and basic yellow 13 (BY13) dyes from binary solutions. Eucalyptus leaves, as a raw material for the production of activated carbon, can be considered as one of the best candidates among the agricultural wastes because it is cheap and quite abundant, especially in arid and semiarid areas like Semnan, Iran.…”