Showing papers by "Centro de Investigación y Desarrollo Tecnológico en Electroquímica published in 1996"
TL;DR: In this article, the current transients obtained from potential step perturbations, show a typical metallic nucleation growth controlled by diffusion, which is influenced by adsorption of the different chemical species on the surface.
Abstract: Gold electrodeposition was studied on glassy carbon and platinum electrodes from Au(1) ammoniacal solution. The current transients obtained from potential step perturbations, show a typical metallic nucleation growth controlled by diffusion. This process is influenced by adsorption of the different chemical species on the surface. Change in the type of nucleation and morphology of the deposit was observed when the nature of the substrate was changed. It was also found that increase in temperature produces modification of the nucleation mechanism.
26 citations
TL;DR: In this paper, the silver reduction process was studied in a new, low cyanide concentration solution in which the predominant species is the ion Ag(CN) 2 - and the pH is fixed by the presence of potassium pyrophosphate.
Abstract: The silver reduction process was studied in a new, low cyanide concentration solution in which the predominant species is the ion Ag(CN) 2 - and the pH is fixed by the presence of potassium pyrophosphate. The electrochemical reduction of silver occurs via an adsorbed electroactive species assumed to be Ag(CN) 2 - . The silver reduction appears to be a quasi-reversible process at 20°C, and its kinetic parameters are presented as well as the effect of temperature in a 10 to 60°C range ; silver reduction is fast when the temperature is high, and the activation energy was evaluated. Linear sweep voltammetry and the use of an electrochemical quartz crystal microbalance prove the existence of the adsorbed electroactive species and additional evidence was found by chronopotentiometry.
19 citations
TL;DR: In this paper, a class of nonincreasing filters and related morphological operations are used to segment and enhance images, and a gradient criterion weighted by an intensity one is used to reduce the sensitivity of these filters.
Abstract: In this paper we study a class of non-increasing filters and related morphological operations in order to segment and enhance images. Both applications, image segmentation and image enhancement, are related by the fact that contrast operators are applied. This is a main remark that will be used to ap;y the filters in order to segment and enhance images. We will show that a gradient criterion weighted by an intensity one allows us to reduce the sensitivity of these filters. We present some results by means of a contrast-oriented segmentation. By combining the filters and using a geodesic application, we extract flat zones in order to segment an image.
2 citations