Efficient Medical Image Classification Using Masked Attention Networks

Abstract

Textile dyes are chemically stable, intensely colored pollutants that can resist conventional biological treatment and reduce light penetration in receiving waters. Titanium dioxide (TiO₂) photocatalysis offers a destructive advanced-oxidation route in which light-generated electron-hole pairs form reactive oxygen species capable of attacking dye chromophores and, with sufficient treatment, mineralizing organic carbon. This methodology paper develops a kinetic framework for comparing three TiO₂-based nanomaterials—commercial P25 TiO₂, nitrogen-doped TiO₂ (N-TiO₂), and nickel-sulfur co-doped TiO₂ (Ni-S/TiO₂)—for degradation of Reactive Black 5 (RB5) and methylene blue (MB). The workflow combines catalyst synthesis/selection, XRD, FTIR, SEM/TEM and UV-Vis diffuse-reflectance characterization, batch photoreactor experiments, dark-adsorption controls, UV-Vis concentration monitoring, pseudo-first-order kinetics, Langmuir-Hinshelwood analysis, radical-scavenger tests, and catalyst-reuse assessment. Initial dye concentration, catalyst loading, pH, irradiation time and photon exposure are controlled systematically. The apparent first-order constant (kapp), half-life, percentage degradation, Langmuir-Hinshelwood kinetic parameters, and cycle-to-cycle activity retention are used for comparison. Representative numerical results are included only to demonstrate the intended analysis and are not presented as laboratory measurements. The proposed protocol provides a reproducible basis for connecting TiO₂ nanomaterial modification with dye adsorption, visible-light response and photocatalytic reaction kinetics.