Decolorization of textile dye by Candida albicans isolated from industrial effluents

The aim of the present work was to observe microbial decolorization and biodegradation of the Direct Violet 51 azo dye by Candida albicans isolated from industrial effluents and study the metabolites formed after degradation. C. albicans was used in the removal of the dye in order to further biosorption and biodegradation at different pH values in aqueous solutions. A comparative study of biodegradation analysis was carried out using UV-vis and FTIR spectroscopy, which revealed significant changes in peak positions when compared to the dye spectrum. Theses changes in dye structure appeared after 72 h at pH 2.50; after 240 h at pH 4.50; and after 280 h at pH 6.50, indicating the different by-products formed during the biodegradation process. Hence, the yeast C. albicans was able to remove the color substance, demonstrating a potential enzymatic capacity to modify the chemical structure of pigments found in industrial effluents.

Textile Dye Treated Photoelectrolytically and Monitored by Winogradsky Columns

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ligninolytic activity from newly isolated basidiomycete strains and effect of these enzymes on the azo dye orange II decolourisation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

In vitro evaluation of apical sealing in root apex treated with demineralization agents and retrofiled with mineral trioxide aggregate through marginal dye leakage

O objetivo deste estudo foi avaliar o selamento de ápices radiculares tratados com diferentes agentes desmineralizantes e retrobturados com agregado de trióxido mineral (MTA), mediante infiltração marginal por corante. Cinqüenta e seis dentes unirradiculares humanos extraídos foram instrumentados, obturados e seccionados apicalmente. Os preparos cavitários apicais foram confeccionados com pontas ultra-sônicas e os agentes desmineralizantes foram aplicados previamente à retrobturação com Pro Root MTA. Os espécimes foram divididos aleatoriamente em 4 grupos (n=14): grupo 1 (sem agente desmineralizante); grupo 2 (ácido fosfórico 35% durante 15 s); grupo 3 (solução de EDTA 17%, pH 7, durante 3 min); grupo 4 (gel de EDTA 24%, pH 7, durante 4 min). A extensão da infiltração de corante (rodamina B 2% a 37°C, por 24 h) foi avaliada em milímetros utilizando-se um estereomicroscópio. Os resultados foram analisados estatisticamente por meio de análise de variância a um critério e do teste Tukey com nível de significância de 5%. Dentre os grupos experimentais, a menor extensão de infiltração do corante foi verificada no grupo 1 (1,89 mm), seguido pelos grupos 2 (2,18 mm), 4 (2,54 mm) e 3 (2,64 mm). Não houve diferenças estatisticamente significante (p>0.05) na infiltração marginal pelo corante entre os grupos 1, 2 e 4 e os grupos 2, 3 e 4. Com base nos resultados obtidos, pode-se concluir que a aplicação de agentes desmineralizantes não pode ser recomendada quando da utilização do MTA em cirurgias parendodônticas.

Impedance Spectroscopy Analysis of the Effect of TiO2 Blocking Layers on the Efficiency of Dye Sensitized Solar Cells

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Doping saturation in dye-sensitized solar cells based on ZnO:Ga nanostructured photoanodes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Electron Transport in Dye-Sensitized Solar Cells Based on ZnO Nanotubes: Evidence for Highly Efficient Charge Collection and Exceptionally Rapid Dynamics

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Surface Passivation of Nanoporous TiO2 via Atomic Layer Deposition of ZrO2 for Solid-State Dye-Sensitized Solar Cell Applications

We report here the utilization of atomid layer deposition to passivate surface map states in mosoporous TiO2 nanoparticles for solid state dye sensitized solar cells based on 9,9'-spirobifluorene (spiro-OMeTAD). By depositing ZrO2 films with angstrom-level precision, coating the mesoporous TiO2 produces over a two-fold enhancement in short-circuit current density, as compared to a control device. Impedance spectroscopy measurements provide evidence that the ZrO2 coating reduces recombination lossed at the TiO2/spiro-OMeTAD interface and passivates localized surface states. Low-frequency negative capacitances, frequently observed in nanocomposite solar cells, have been associated with the surface-state mediated charge transfer from TiO2 to the spiro-OMeTAD.

Synthesis and characterization of mesoporous TiO2 nanostructured films prepared by a modified sol-gel method for application in dye solar cells

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Mutagenic activity removal of selected disperse dye by photoeletrocatalytic treatment

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Electrochemical Reduction as a Powerful Tool to Highlight the Possible Formation of By-Products More Toxic Than Sudan III Dye

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Electrochemical reduction of disperse orange 1 textile dye at a boron-doped diamond electrode

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Voltammetric sensing of the fuel dye marker Solvent Blue 14 by screen-printed electrodes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A simple electroanalytical method for the analysis of the dye solvent orange 7 in fuel ethanol

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)