The lattice Boltzmann method (LBM) is a finite element and finite volume method for studying the reaction rate, mass diffusion and concentration of species. We are used the LBM to investigate the effect of the Damköhler number (Da) and Reynolds number (Re) on the laminar flow in a channel with an open square cavity and a reactive bottom wall in two dimensions in a first-order chemical reaction. The reactant A is transported through the cavity, where it undergoes a reaction on the reactive surface, resulting in the synthesis of product B. The effect of Da < 1 on the reaction rate is negligible for all investigated Re values; the generation of product B is slower because of the effect of the momentum diffusivity on the velocity inside the cavity. For Re = 5 and 1 < Da ≤ 100, the concentration of B inside the cavity reaches the maximum for Da = 100, and A is absorbed almost entirely on the bottom of the cavity. In our simulations, we observed that for all values of Re and Da > 100, the effect of the momentum diffusivity is negligible in the cavity, and the reaction on the surface is almost instantaneous.
En el presente proyecto se propone el estudio paramétrico de un modelo constitutivo de análisis de respuesta de sitio para el estudio de variables a tener en cuenta en sitios expuestos a posibles eventos de licuación y además que tiene aplicaciones en la ingeniería sísmica, donde la mayoría de casos existentes son resueltos utilizando alternativas de solución empíricas y las alternativas de solución numéricas cada vez están ganando terreno en el campo de la ingeniería sísmica aplicada en su uso cotidiano.
The contamination of aquatic ecosystems by the micropollutants in wastewater discharges is currently a critical issue. Therefore, the development of novel treatment processes and materials is essential to ensure the availability of safe water. The present study aims to develop a photocatalytic material composed of silver nanoparticles (Ag-NPs)-doped TiO2 supported on a Pyrex® plate (TiO2@Ag-NPs) exhibiting catalytic activity under visible irradiation (λ > 400 nm). The effects of Ag-NPs doping on the TiO2 matrix, the resistance of the coating at the catalyst/substrate interface, and the photocatalytic degradation efficiency of the photocatalyst for a micropollutant (diuron) of the pesticide family were studied. The photocatalyst was characterised using X-ray diffraction, scanning electron microscopy, ultraviolet–visible spectrophotometry, and scratch tests. The solution concentrations were monitored using high-performance liquid chromatography and total organic carbon analyses. A 32% diuron removal was achieved using photocatalytic TiO2@Ag-NPs under visible irradiation, whereas undoped TiO2 showed no activity. Furthermore, the effects of the nanoparticle growth mode on the photocatalytic activity of TiO2@Ag-NPs were explored. The presence of a TiO2 sublayer ensured the adhesion of the coating and promoted the dispersion of nanoparticles within the matrix. It ensured chemical continuity (TiO2@Ag-NPs/Pyrex®), reduced the bandgap, and decreased electron–hole pair recombination.