Electrochemical Determination of Organic Compounds in Automotive Fuels

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Microstructural and electrochemical characterization of friction stir welded duplex stainless steels

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

On the Electrochemical Deposition and Dissolution of Divalent Metal Ions

The deposition of Cu2+ and Zn2+ from aqueous solution has been investigated by a combination of classical molecular dynamics, density functional theory, and a theory developed by the authors. For both cases, the reaction proceeds through two one-electron steps. The monovalent ions can get close to the electrode surface without losing hydration energy, while the divalent ions, which have a stronger solvation sheath, cannot. The 4s orbital of Cu interacts strongly with the sp band and more weakly with the d band of the copper surface, while the Zn4s orbital couples only to the sp band of Zn. At the equilibrium potential for the overall reaction, the energy of the intermediate Cu+ ion is only a little higher than that of the divalent ion, so that the first electron transfer can occur in an outer-sphere mode. In contrast, the energy of the Zn+ ion lies too high for a simple outer-sphere reaction to be favorable; in accord with experimental data this suggests that this step is affected by anions.

Are new TiNbZr alloys potential substitutes of the Ti6Al4V alloy for dental applications? An electrochemical corrosion study

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

Electrochemical studies based on local interfacial ph changes of gold nanoparticles immobilized on polystyrene brushes

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

Electrochemical investigations on the capacity of flavonoids to protect DNA against damage caused by textile disperse dyes

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

Highly Ordered TiO2 Nanotubes for Electrochemical Sensing of Hair Dye Basic Brown 17

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

A Silsesquioxane Organically Modified with 4-Amino-5-(4-pyridyl)-4H-1,2,4-triazole-3-thiol: Thermal Behavior and Its Electrochemical Detection of Sulfhydryl Compounds

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

An Electrochemical Sensor for Reducing Sugars Based on a Glassy Carbon Electrode Modified with Electropolymerized Molecularly Imprinted Poly-o-phenylenediamine Film

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

Electrochemical Properties of the Oxo-Manganese-Phenanthroline Complex Immobilized on Ion-Exchange Polymeric Film and Its Application as Biomimetic Sensor for Sulfite Ions

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

Highly Sensitive Electrochemical Sensor for Determination of Vitamin D in Mixtures of Water-Ethanol

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

Phenomenological model for the interpretation of impedance/admittance spectroscopy results in polymer light-emitting electrochemical cells

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

Impedance-derived electrochemical capacitance spectroscopy for the evaluation of lectin-glycoprotein binding affinity

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

Electrochemical kinetic study of surface layer growth on natural pyrite in acid medium

This paper presents electrochemical experiments on natural pyrite that combine potentiostatic and voltammetric techniques. X-ray microanalysis is used as an auxiliary technique. The layer growth on pyrite surface is conducted in a wide range of pH and potential range: 3.4 <= pH <= 5.9 with E = 0.80 V (versus SHE), and 0.80 V <= E <= 1.00 V with pH 4.5 (versus SHE) in acetic acid-acetate buffer. This work is unique for two reasons: (1) phenomenological model about layer growth is applied and mathematical-physic consistence is verified and (2) Meyer's hypotheses of chemical mechanism are used to explain kinetic parameters of the phenomenological model. (c) 2005 Elsevier B.V. All rights reserved.

Towards the abatement of environmental mercury pollution: An electrochemical characterization

Electrochemical experiments in acetic acid-acetate buffer (pH 4.5) are conducted in order to understand metallic and ionic mercury adsorption processes on the pyrite surface. The nature as well as the extent of the spontaneous interaction between pyrite and mercuric ions was evaluated. The spontaneous reduction of mercury species onto pyrite surface was confirmed. These results represent a first step for the use of mining wastes rich in pyrite for mercury pollution abatement. (c) 2005 Elsevier B.V. All rights reserved.