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Electrochemical behavior of dopamine in presence of Ascorbic Acid by using an electrochemical modified gold electrode and an electrochemical and chemical modified gold electrode with a thiol
Menolasina,Sabino; Contreras,Ricardo R; Aguilar,Anfrelis; Contreras,Olga; Rodríguez,Alexis;
Revista Técnica de la Facultad de Ingeniería Universidad del Zulia , 2007,
Abstract: this paper presents the results about the detection and quantification of dopamine (da) in presence of ascorbic acid (aa) by using an electrochemical modified gold electrode and an electrochemical and chemical modified gold electrode with a self assembled monolayer of a novel compound, the n-methyl-1-cyclopenten-2-dithiocarboxylic acid. the cyclic voltammetry (cv) and square wave voltammetry (swv) techniques were using for these experiments
ELECTROCHEMICAL INVESTIGATION OF CYSTEAMINE AT CARBON FIBER MICRODISK ELECTRODE
EL-HALLAG,IS; AL-YOUBI,A.O; OBAID,A.Y; EL-MOSSALAMY,E.H; EL-DALY,S.A; ASIRI,A.M;
Journal of the Chilean Chemical Society , 2011, DOI: 10.4067/S0717-97072011000400003
Abstract: the electrooxidation of cysteamine compound was carried out using convolutive cyclic voltammetry, linear sweep voltammetry and chronoamperomtry techniques at a carbon fiber microdisk electrode in 0. 1 m perchloric acid. the electrooxidation potential (e0'' ) of cysteamine occurs at + 0.921 v. the mechanistic pathway of electrooxidation process at carbon fiber microelectrode is loss of 1 electron per molecule. the electrode process is controlled mainly by diffusion. the chemical and electrochemical parameters of the investigated system were determined experimentally and verified theoretically via digital simulation method.
ELECTROCHEMICAL INVESTIGATION OF CYSTEAMINE AT CARBON FIBER MICRODISK ELECTRODE  [cached]
IS EL-HALLAG,A.O AL-YOUBI,A.Y OBAID,E.H EL-MOSSALAMY
Journal of the Chilean Chemical Society , 2011,
Abstract: The electrooxidation of cysteamine compound was carried out using convolutive cyclic voltammetry, linear sweep voltammetry and chronoamperomtry techniques at a carbon fiber microdisk electrode in 0. 1 M perchloric acid. The electrooxidation potential (E0'' ) of cysteamine occurs at + 0.921 V. The mechanistic pathway of electrooxidation process at carbon fiber microelectrode is loss of 1 electron per molecule. The electrode process is controlled mainly by diffusion. The chemical and electrochemical parameters of the investigated system were determined experimentally and verified theoretically via digital simulation method.
Study on the Electrode Materials of Electrochemical Capacitor  [cached]
Xiaolai Liu,Jin Li
International Journal of Chemistry , 2011, DOI: 10.5539/ijc.v3n2p198
Abstract: Super capacitor is a kind of new energy-storage component developed in recent years, with many advantages such as large energy-storage capacity, light quality, pollution free, multiple charging and discharging. Starting from the principle, development, and application of capacitor, the electrode materials including activated carbon fiber, carbon nano tube (CNT), ordered mesoporous carbon, and graphene used for the super capacitor are introduced in this article.
Three electrode electrochemical microfluidic cell: construction and characterization
Silva, Rodrigo A. B. da;Almeida, Edimar G. N. de;Rabelo, Adriano C.;Silva, Abílio T. C. da;Ferreira, Lucas F.;Richter, Eduardo M.;
Journal of the Brazilian Chemical Society , 2009, DOI: 10.1590/S0103-50532009000700006
Abstract: this work describes the construction and characterization of an electrochemical flow-through microcell with the three electrodes (working, pseudo-reference, and auxiliary) inserted in microchannels with thickness smaller than 20 μm. these microchannels were constructed between two stacked polycarbonate slides using one or more overlapped toner masks as spacer. this strategy allows the construction of microcells with a variable internal volume on the working electrode (0.6 to 2.4 μl). three different materials were optimized as electrodes: gold film or graphite-epoxy composite as working electrode, silver-epoxy composite as pseudo-reference electrode and, graphite-epoxy composite as auxiliary electrode. the performance of the microfluidic cell was characterized by cyclic voltammetry, potentiometric stripping analysis at constant current, and square wave anodic stripping voltammetry using ferrocyanide and heavy metals (cu2+, hg2+, pb2+, and cd2+) as model analytes.
Dynamics of electrochemical flows 2 Electrochemical flows-through porous electrode  [PDF]
Chengjun Xu,Chin-Tsau Hsu
Physics , 2013,
Abstract: The electrolyte (comprising of solute ions and solvents) flow-through the porous media is frequently encountered in nature or in many engineering applications, such as the electrochemical systems, manufacturing of composites, geothermal engineering, soil pollution. In this study, we provide a new general theory for the electrochemical flows-through porous media. We use static method and set up two representative elementary volumes (REVs). One is the macroscopic REV of the mixture of the porous media and the electrolyte, while the other is the microscopic REV in the electrolyte fluid. The establishment of two REVs enables us to investigate the details of transports of mass, heat, electric flied, or momentum in the process of the electrochemical flows-through porous electrode. In this work, the macroscopic governing equations are derived from the conservation laws in the macroscopic REV to describe the electrochemical flows-through porous media. At first, we define the porosity by the volume and surface and divide the porous media into various categories. Then the superficial average is transformed into intrinsic averages to derive the interaction terms between the solid and the fluid, known as terms of dispersion, tortuosity and interfacial transfer. The macroscopic governing equations are derived by performing the intrinsic average on the microscopic governing equations. After done that, the unknown terms related to the dispersion, tortuosity and interfacial transfer are emerged in the governing equations.
Effect of carboxylate compounds on the electrochemical behavior of dopamine at a mercury electrode
Winter, Eduardo;Carvalho, Rosangela M. de;Kubota, Lauro T.;Rath, Susanne;
Journal of the Brazilian Chemical Society , 2003, DOI: 10.1590/S0103-50532003000400012
Abstract: the electrochemical oxidation of dopamine leads to deposition of polymeric films on the surfaces of solid state electrodes, decreasing the electrode activity. with a mercury electrode, the oxidation of dopamine occurs in the potential region of mercury oxidation. however, in the presence of carboxylic compounds the cyclic voltammogram of dopamine is different and presents a new electroactive product resulting from the oxidation of dopamine. this work describes preliminary results for the electrochemical behavior of dopamine at the hg-electrode in the presence of acetate, citrate and edta.
Effect of carboxylate compounds on the electrochemical behavior of dopamine at a mercury electrode  [cached]
Winter Eduardo,Carvalho Rosangela M. de,Kubota Lauro T.,Rath Susanne
Journal of the Brazilian Chemical Society , 2003,
Abstract: The electrochemical oxidation of dopamine leads to deposition of polymeric films on the surfaces of solid state electrodes, decreasing the electrode activity. With a mercury electrode, the oxidation of dopamine occurs in the potential region of mercury oxidation. However, in the presence of carboxylic compounds the cyclic voltammogram of dopamine is different and presents a new electroactive product resulting from the oxidation of dopamine. This work describes preliminary results for the electrochemical behavior of dopamine at the Hg-electrode in the presence of acetate, citrate and EDTA.
Preparation of Ag Nanowire Array Electrode by Transplantation and its Electrochemical Activities
Chao Kong, Zhong-ai Hu, Hong-xiao Zhao, Yu-ying Yang, Xiu-li Shang, Li-jun Ren, Yan-peng Wang
International Journal of Electrochemical Science , 2007,
Abstract: Ordered Ag nanowire array electrodes were prepared by transplantation, in which Ag nanowire array embedded in anodic aluminium oxide (AAO) template was transplanted onto the surface of kryptol electrode. Its morphology was observed by scanning electron microscope (SEM) and the electrochemical behaviors for methylene blue were investigated by means of cyclic voltammertry. The experimental results show that the array electrode exhibits high electrocatalytic activities of methylene blue on the Ag nanowire array electrode.
Dithiooxamide Modified Glassy Carbon Electrode for the Studies of Non-Aqueous Media: Electrochemical Behaviors of Quercetin on the Electrode Surface  [PDF]
Ay?en Demir Mülaz?mo?lu,Ecir Y?lmaz,?brahim Ender Mülaz?mo?lu
Sensors , 2012, DOI: 10.3390/s120403916
Abstract: Electrochemical oxidation of quercetin, as an important biological molecule, has been studied in non-aqueous media using cyclic voltammetry, electrochemical impedance spectroscopy and scanning electron microscopy. To investigate the electrochemical properties of quercetin, an important flavonoid derivative, on a different surface, a new glassy carbon electrode has been developed using dithiooxamide as modifier in non-aqueous media. The surface modification of glassy carbon electrode has been performed within the 0.0 mV and +800 mV potential range with 20 cycles using 1 mM dithioxamide solution in acetonitrile. However, the modification of quercetin to both bare glassy carbon and dithiooxamide modified glassy carbon electrode surface was carried out in a wide +300 mV and +2,800 mV potential range with 10 cycles. Following the modification process, cyclic voltammetry has been used for the surface characterization in aqueous and non-aqueous media whereas electrochemical impedance spectroscopy has been used in aqueous media. Scanning electron microscopy has also been used to support the surface analysis. The obtained data from the characterization and modification studies of dithioxamide modified and quercetin grafted glassy carbon electrode showed that the developed electrode can be used for the quantitative determination of quercetin and antioxidant capacity determination as a chemical sensor electrode.
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