Effect of hydrogen charging on the stability of SAE 10B22 steel surface in alkaline solutions

The influence of hydrogen charging into a quenched and tempered boron steel membrane electrode (SAE 10B22) was studied using borate buffer (pH 8.4) and NaOH solutions (pH 12.7), with or without the addition of 0.01 M EDTA. At the hydrogen input side, hydrogen charging influenced cyclic voltammograms increasing the anodic charge of iron(II) hydroxide formation, and decreasing the donor density of passive films. These results suggest that the hydrogen ingress caused instability of metallic surface, increasing the surface area activity. (C) 2005 Elsevier Ltd. All rights reserved.

Aplicação de técnicas eletroquímicas no estudo da dissolução oxidativa da covelita (CuS) por Thiobacillus ferrooxidans

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

Optimization of the use of carbon paste electrodes (CPE) for electrochemical study of the chalcopyrite

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

Electrochemical behavior of Ti-Mo alloys applied as biomaterial

Electrochemical investigation on the as-cast Ti-Mo alloys (4-20 Mo wt.%) applied as biomaterials in Na2SO4 and Ringer physiological solutions is reported. Analyses of the open-circuit potential indicated that all alloys present spontaneous passivation. SEM and cyclic voltammograms obtained in the Ringer solution showed that the samples studied do not present pitting corrosion at potentials up to 8 V (SCE), indicating high corrosion resistance. Open-circuit potential profiles of the anodic oxides growth in both solutions show that the presence of chloride ions during the anodization does not influence the oxides' chemical stability, and also clearly indicate that adding Mo to pure Ti improves the stability of the anodic oxides. All these results suggest Ti-Mo alloys promissory to be applied as biomaterials. (c) 2008 Elsevier Ltd. All rights reserved.

Electrochemical Behavior of a Glassy Carbon Electrode Chemically Modified with Nickel Pentacyanonitrosylferrate in Presence of Sulfur Compounds

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

Effects of Alloyed and Oxide Phases on Methanol Oxidation of Pt-Ru/C Nanocatalysts of the Same Particle Size

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

Local Electrochemical Investigation of Single Grains of Polycrystalline Cu-16%Zn-8%Al Alloy

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

Alloys and oxides on carbon-supported Pt-Sn electrocatalysts for ethanol oxidation

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

Platinum-coated nanostructured oxides for active catalytic electrodes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Electrochemical and spectroscopic characterization of screen-printed gold-based electrodes modified with self-assembled monolayers and Tc85 protein

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

Electrochemical reduction and cathodic stripping voltammetric determination of clotrimazole

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

Electrochemical evaluation of lipophilic antioxidants from Iryanthera juruensis fruits (Myristicaceae)

Testes em placas de CCDC reveladas com solução de beta-caroteno mostraram a presença de duas substâncias com propriedades antioxidantes no extrato hexânico. Elas foram isoladas e identificadas como 3-metil-sargacromenol (1) and sargacromenol (2). O extrato hexânico forneceu ainda o ácido 3-metil-sargaquinóico (3) e o ácido sargaquinóico (4). O comportamento eletroquímico destas substâncias foi investigado em CH2Cl2/Bu4NBF4 sobre eletrodo de carbono vítreo. A oxidação do grupo fenólico nos tocotrienóis 1 and 2 é responsável por um pico anódico em potenciais de +0.23V e +0.32V, os quais são correlacionados com sua atividade antioxidante. O mecanismo de oxidação é comparado com o comportamento eletroquímico do antioxidante alfa-tocopherol.

Electrochemical behavior of a glassy-carbon electrode chemically modified with cadmium pentacyanonitrosylferrate in the presence of tetrahydrothiophene

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

Preparation and Characterization of Graphite-Epoxy Composite Modified with Zinc Hexacyanoferrate and Their Electrochemical Behaviour in Presence of Substituted Anilines

The growth of zinc hexacyanoferrate (ZnHCF) hybrid film on the surface of graphite-epoxy composite (GEC) electrodes was demonstrated by cyclic voltammetry. Surface morphology of the hybrid film was investigated by using scanning electron microscopy. The effect of the type of monovalent cations on the redox behaviour of hybrid film was also studied. This effect indicated that the radius of the hydrated cation mainly determines the ion permeability of the film.The electrochemical behavior of the substituted anilines (procaine and sulfamerazine) in 1 M KCl of the modified GEC electrode showed a decrease of the cathodic currents while increasing the concentration of these analytes. The developed sensor also showed excellent stability for long time usage, higher sensitivity and cost-effective fabrication.

Silver Nanocomposite Electrode Modified with Hexacyanoferrate. Preparation, Characterization and Electrochemical Behaviour Towards Substituted Anilines

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)