Chapters authored
Advanced Oxidation Process Applied to Actinobacterium Disinfection
Actinobacteria, such as Mycobacterium, that constitute one of the main phyla within the bacteria and some genus of this phylum are reported to be a pathogen of or associated with nosocomial infections and pseudoinfections promoting health risks for immunocompromised people, particularly AIDS patients. They are also related to lower quality of surface water due to their odor production (Actinomycineae and Streptomycetaceae). These bacteria have been isolated from hospital water distribution systems, municipal drinking water, freshwater, and among other environmental samples. Their biofilm formation, amoeba-associated lifestyle, and resistance to chlorine/ozone have been recognized as important factors that contribute to persistence of these bacteria in water distribution systems. Research for new disinfection methods that are able to promote complete inactivation of these bacteria has currently increased. Among them is the use of advanced oxidation process that has demonstrated promising results; the production of ⋅OH radicals with high oxidizing power are capable to kill bacteria and can also destroy the products generated from lyse cell. The goal of the present work is to review the main processes based on advanced oxidation process that are able to promote actinobacterium disinfection. The fundaments of this process are also reviewed. Special emphasis was done for the photocatalysis and photoelectrocatalysis methods and the phenomena occurring at the electrode/electrolyte interface.
Part of the book: Actinobacteria
Advances and Trends in Voltammetric Analysis of Dyes
Since 1856 when W. H. Perkin synthesized the first synthetic dye (Mauveine), a wide variety of colors and shades are produced and used in several commercial products. The occurrence in water and wastewater has gained controversy regarding their toxicity and mutagenicity and it has been regulation by several regulatory agencies. Thus, analytical methods able to determine these colorings in several matrices with high sensitive and robust enough are relevant. Among several analytical methods, the use of electroanalytical methods, especially the voltammetric techniques, are of great interest due to the high selectivity, sensitivity, use of low quantity of sample, little or without sample treatment, and low waste generation, which contributes to reduced environmental impact. Over the past decades, the technical based on current-potential curves by using of static electrodes have gained considerable progress, as minimizing the effect of capacitive current and the possibility of pre-concentration of the analyte at the electrode surface, which has reflected in lower detection levels. The present work gives an overview about the analytical methods available in literature focusing on electroanalysis of dyes by using voltammetric techniques. The advances of the electroanalytical techniques and the use of different modifiers to increase sensitivity and selectivity are reviewed.
Part of the book: Applications of the Voltammetry