Multivariate Analysis of Digital Images as an Alternative to Monitor Dye Degradation by the Fenton Process

Abstract

The present work proposed the application of a multivariate regression model based on image data to monitor the decolorization process. Thus, a PLS regression based on the color histogram was applied to monitor the methylene blue degradation by the Fenton reaction. The results obtained by the digital imaging and UV-Vis methods were compared and the initial (C o) and final (C) methylene blue concentrations, as well as the kinetic parameters, coefficients of determination (R 2), half time degradation (t ½), intercept (ρ), and slope (σ), were evaluated. From our results, the digital imaging and UV-Vis methods have equivalent potential to monitor the color removal profile, similar kinetic term, and low measurement errors. While the coefficient of determination (R 2) of all PLS models and kinetics curves are close to 1.00, the half time degradation (t ½) parameter ranged between 0.29 to 1.39 min for the UV-Vis model, and 0.80 min to 2.17 min for the digital imaging model. Furthermore, the efficiency of methylene blue removal ranged between 92.04% and 97.78% for the UV-Vis model and 91.30% to 93.72% for the digital imaging model. Then, based on statistical comparison tests, it was concluded that the digital imaging method is an alternative to monitor dye degradation processes.

Interpol questioned documents review 2019–2022

“…including any other technology used to prepare the document. The following 64 articles [ [548] , [549] , [550] , [551] , [552] , [553] , [554] , [555] , [556] , [557] , [558] , [559] , [560] , [561] , [562] , [563] , [564] , [565] , [566] , [567] , [568] , [569] , [570] , [571] , [572] , [573] , [574] , [575] , [576] , [577] , [578] , [579] , [580] ] [ [581] , [582] , [583] , [584] , [585] , [586] , [587] , [588] , [589] , [590] , [591] , [592] , [593] , [594] , [595] , [596] , [597] , [598] , [599] , [600] , [601] , [602] , [603] , [604] , [605] , [606] , [607] , [608] , [609] , [610] , [611] ], combined with 17 presentations [...…”

“…Santos et al [ 582 ] used an alternate method to monitor dye degradation in their attempts to determine the date of production of documents. Their work proposed the application of a multivariate regression model based on image data to monitor this decolorization process in the dyes.…”