Publications by authors named "Carlos F Zinola"

Studying the growth and stability of anisotropic or isotropic disordered surfaces in electrodeposition is of importance in catalytic electrochemistry. In some cases, the metallic nature of the electrode defines the topography and roughness, which are also controlled by the experimental time and applied external potential. Because of the experimental restrictions in conventional electrochemical techniques and ex situ electron microscopies, a theoretical model of the surface geometry could aid in understanding the electrodeposition process and current distributions.

View Article and Find Full Text PDF

Cystathionine beta-synthase (CBS) catalyzes the condensation of serine and homocysteine to cystathionine, which represents the committing step in the transsulfuration pathway. CBS is unique in being a pyridoxal phosphate-dependent enzyme that has a heme cofactor. The activity of CBS under in vitro conditions is responsive to the redox state of the heme, which is distant from the active site and has been postulated to play a regulatory role.

View Article and Find Full Text PDF

A catalytic effect is found for methanol oxidation after new active surface states are produced on polycrystalline platinum by potentiostatic cathodization in acid media at room temperature. This procedure originates surface states not available on the original polycrystalline electrodes with unexpected cyclic voltammetric responses; i.e.

View Article and Find Full Text PDF

Three cationic complexes containing the [Re((V))O](3+) core (general formula [ReO(dien-H)(aa)](+), dien=diethylenetriamine, aa=glycine, alanine, valine) were studied on polycrystalline Au electrodes employing cyclic voltammetry techniques. The electrochemical behavior of the amino acids (aa) was also evaluated. Experiments were performed at pH 7.

View Article and Find Full Text PDF

The actual state of the art in the reduction of perrhenate ions on noble metals is reviewed and discussed. Also, with the aim of contributing to better knowledge of this process, results of several experiments are presented. For the first time, spectroscopic evidence on the nature of the deposited rhenium layer on Pt and Rh and the detection of an intermediate in the reduction pathway toward metallic rhenium is provided.

View Article and Find Full Text PDF

The electrochemical behavior of trans-[Re((V))O(2)(en)(2)]I and trans-[Re((V))O(2) (en)(2)]ClO(4) (en=ethylenediamine) complexes was studied by cyclic voltammetry on Au electrodes. Experiments were performed in aqueous solutions at pH 7.0 and at room temperature.

View Article and Find Full Text PDF