Determination of Ionic and Electronic Resistivities in Carbon/Polyelectrolyte Fuel-Cell Composite Electrodes

2002 ◽  
Vol 149 (12) ◽  
pp. A1541 ◽  
Author(s):  
Andrew P. Saab ◽  
Fernando H. Garzon ◽  
Thomas A. Zawodzinski
Keyword(s):  
Fuel Cell ◽  
Composite Electrodes

Use of beeswax as an alternative binder in the development of composite electrodes: an approach for determination of hydrogen peroxide in honey samples

2021 ◽  
pp. 138876
Author(s):  
Paulo Roberto de Oliveira ◽  
Cristiane Kalinke ◽  
Juliano Alves Bonacin ◽  
Luiz Humberto Marcolino-Junior ◽  
Marcio Fernando Bergamini ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Composite Electrodes

Determination of the efficiency of methanol oxidation in a direct methanol fuel cell

2016 ◽  
Vol 199 ◽  
pp. 210-217 ◽  
Author(s):  
Pasha Majidi ◽  
Rakan M. Altarawneh ◽  
Nicholas D.W. Ryan ◽  
Peter G. Pickup
Keyword(s):  
Fuel Cell ◽  
Methanol Oxidation ◽  
Direct Methanol Fuel Cell ◽  
Direct Methanol ◽  
Methanol Fuel Cell

scholarly journals Study of Dual Stator Induction Motor in Photovoltaic-Fuel Cell Hybrid Pumping Application

2020 ◽  
Vol 53 (5) ◽  
pp. 601-608
Author(s):  
Arezki Adjati ◽  
Toufik Rekioua ◽  
Djamila Rekioua ◽  
Abdelmounaim Tounzi
Keyword(s):  
Fuel Cell ◽  
Induction Motor ◽  
Centrifugal Pump ◽  
Cell Hybrid ◽  
Double Star ◽  
Water Requirements ◽  
Matlab Simulink ◽  
Pumping System ◽  
Dynamic Head

This paper discusses the modeling of hybrid Photovoltaic/Fuel cell pumping. This system comprises a photovoltaic generator and a fuel cell, two DC/DC converters, two of inverters which supply a double star induction motor (DSIM) which drives the shaft of a centrifugal pump. The evaluation of the water requirements, the total dynamic head (TDH) and the flow are of great importance to evaluate the various powers allowing the determination of the size of the pumping system. The global proposed system is sized and simulated under Matlab/Simulink Package. The obtained results under different metrological conditions show the effectiveness of the proposed hybrid pumping system.

scholarly journals Characterization of graphite-epoxy composite electrodes for free electrochemical detection of adenine and guanine in DNA

2021 ◽  
Author(s):  
Abel Ibrahim Balbin Tamayo ◽  
Leodanis Correa Fajardo ◽  
Ana Margarita Esteva Guas
Keyword(s):  
Square Wave Voltammetry ◽  
Construction Materials ◽  
Composite Electrodes ◽  
Single Chain ◽  
Electron Transfer Rate ◽  
Redox Probe ◽  
Wave Voltammetry ◽  
Electron Transfer Rate Constant

Graphite-epoxy composites (GECs) are alternative construction materials for electro­chemical sensors. For these materials, the electron transfer rate constant of some redox reaction depends additionally on the stoichiometric relationship between the insulating and conducting phases of the composite. In this work, the influence of dif­fe­rent ratios of araldite/hardener/graphite on the electrochemical properties of GEC electrodes is evaluated for the simultaneous determination of adenine and guanine in the single chain DNA, using the square wave voltammetry technique. Six GEC electro­des were prepared with different ratios of components, and electrochemically charac­terized by cyclic voltammetry in the presence of ferri/ferrocyanide redox couple as a redox probe. GEC electrodes that showed the best electrochemical responses of redox probe were characterized by thermogravimetric analysis (TGA) and used for the simul­taneous determination of free adenine and guanine in a solution, and DNA oligonu­cle­otides. The best results were obtained for GEC electrodes containing twice higher volu­me of araldite resin with respect to the hardener. TGA analysis revealed presence of 15-26 % of resin for these GEC electrodes. The obtained results revealed potential appl­ication of these GEC electrodes as DNA sensors based on the oxidation signal of guanine.

scholarly journals Electrodeposition of 4-Benzenesulfonic Acid onto a Graphite-Epoxy Composite Electrode for the Enhanced Voltammetric Determination of Caffeine in Beverages

2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Leonardo de A. Furtado ◽  
Mariana C. de O. Gonçalves ◽  
Carlos V. M. Inocêncio ◽  
Edilson M. Pinto ◽  
Daniela de L. Martins ◽  
...  
Keyword(s):  
Composite Electrode ◽  
Epoxy Composite ◽  
Reference Method ◽  
Diazonium Salts ◽  
Composite Electrodes ◽  
Wave Voltammetry ◽  
Linear Behaviour ◽  
Chromatographic Procedure ◽  
Kinetics Of

Caffeine is widely present in food and drinks, such as teas and coffees, being also part of some currently commercialized medicines, but despite its enhancement on several functions of human body, its exceeding use can promote many health problems. In order to develop new fast approaches for the caffeine sensing, graphite-epoxy composite electrodes (GECE) were used as substrate, being modified by different diazonium salts, synthetized as their tetraflouroborate salts. An analytical method for caffeine quantification was developed, using sware wave voltammetry (SWV) in Britton–Robinson buffer pH 2.0. Detection limits for bare electrode and 4-benzenesulfonic modified electrode were observed circa 145 µmol·L−1 and 1.3 µmol·L−1, respectively. The results have shown that the modification shifts the oxidation peaks to lower potential. Kinetics of the reaction limited by diffusion was more expressive when caffeine was added to the solution, resulting in decreases of impedance, characterized by lower Rct. All results for caffeine determination were compared to a reference chromatographic procedure (HPLC), showing no statistical difference. Analytical parameters for validation were suitably determined according to local legislation, leading to a linear behaviour from 5 to 150 µmol·L−1; precision of 4.09% was evaluated based on the RDC 166/17, and accuracy was evaluated in comparison with the reference method, with recovery of 98.37 ± 2.58%.

Sign in / Sign up

Export Citation Format

Share Document