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Showing 1 to 18 of 18 for “"polarization curves"”.
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Investigation of the Effect of Catalyst Layer Composition on the Performance of PEM Fuel Cells
… surface area is held constant. For each MEA, polarization curves are determined at common operating conditions. The polarization curves are compared to assess the effects of the catalyst layer composition. The results show that both Nafion and carbon content significantly affect MEA …
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An Investigation of Low Temperature Direct Propane Fuel Cells
… dynamics (CFD), specifically FreeFem++ software. Polarization curves predicted by the CFD model were used to understand fuel cell performance. The predictions obtained from the computational fluid dynamics mathematical model for the fuel cell were compared with experimental results. The …
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Electrochemical analysis of active species in a low iron content oxygen reduction reaction catalyst and aluminium covetic materials
… covetic Al materials were also studied. Linear polarization curves show that the corrosion potential of covetic materials is increased compared to base alloy materials. However, Tafel fitting of the polarization curves indicate the rate of corrosion is also increased for covetic Al materials.
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An Investigation of Different Methods of Fabricating Membrane Electrode Assemblies for Methanol Fuel Cells
… MEAs were evaluated using a potentiostat. Polarization curves and power density curves were produced to compare the performance of the cells and gain insight into the effects of various parameters on fuel cell performance. Finally, based on the difficulties experienced and the lessons …
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A Rubric for Electrochemical Testing of Metallic Biomaterials
… non-welded. Linear, potentiodynamic, and cyclic polarization curves were produced by the PARC 2273 potentiostat showing the corrosion tendencies of the metals in four unique solutions 3.5% NaCl, 0.35% NaCl, phosphate buffered saline solution (PBS), and Butterfield phosphate buffered solution …
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Experimental Investigation of the Effect of Composition on the Performance and Characteristics of PEM Fuel Cell Catalyst Layers
… constant. For each catalyst layer composition, polarization curves are measured to evaluate cell performance at common operating conditions, Electrochemical Impedance Spectroscopy (EIS), and Cyclic Voltammetry (CV) are then applied to investigate the cause of the observed variations in …
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Síntese e caracterização de ligas nanocristalinas à base de cobre e zircônio com elevada capacidade de formação de estado vítreo
… through nanoindentation, potentiodynamic polarization and hydrogenation followed by thermal dessorption spectrometry experiments. Nanoindentation results did not show appreciable difference between samples produced conventionally and with suction casting. Potentiodynamic polarization …
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Application of voltammetry to copper electrodeposition
… Shifts and relative differences between the polarization curves were also noted with changing temperature.</p> <p>The results of this investigation indicate that there is a definite correlation between type and concentration of addition agent and voltammogram. The substrate used in the …
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Potentiostatic polarization and the corrosion of nickel-chromium- iron-molybdenum alloy 825
… and air-saturated acids, using potentiostatic polarization techniques. Anodic polarization curves were obtained by changing the potential of an Incoloy 825 test electrode and measuring the resulting current. In both acids, there is no difference in the polarization characteristics in air-or …
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A model-based approach for the development of a bioelectrochemical sensor for biochemical oxygen demand in wastewater
… thereby generating a measurable current. A polarization curve measures the response of the current generated to changes in the anode potential. In this study, four continuously operated microbial electrolysis cells with two different anode materials with differing surface properties have …
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Investigation of an alternative sulfonated silane in ceramic carbon electrodes for fuel cell applications
… at both high and low relative humidities through polarization curves when compared to the TPS/TEOS and Nafion ionomers. The results obtained have determined that an optimization of the sulfonated to unsolfonated ratio has to be altered in order to gain a performance similar to that of the TPS …
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Formation and Quantification of Corrosion Deposits in the Power Industry
… Electrochemical impedance spectroscopy and polarization curves were used to study the interaction mechanism between DBU solution and inconel alloys 600 and 690 at steamgenerator operating temperatures and pressures. Of all the amines used in this study (DMA, DBU, ETA, and morpholine), DMA …
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Assessment of the corrosion behaviour of alloys 825 and 625 in stagnant seawater-effect of temperature and welding
… weldment have been investigated. Potentiodynamic polarization curves for the alloys were recorded in synthetic seawater across a range of temperatures (30 to 60°C). Mixed potential theory was applied to determine corrosion potentials, rates of corrosion and predict the galvanic effect of coupling …
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Synthesis and characterization of functional polymers with controlled architecture and their application as anticorrosion primers
… electrochemical impedance spectroscopy, polarization curves and pull-off test). A deposition method was developed to generate the optimal coating system: the steel to protect was dipped in a dilute solution of the copolymer, rinsed with pure solvent to eliminate the excess material and …
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Computational and adsorption investigation of some quinoxaline derivatives on selected metals in acidic media
… spectroscopy (EIS), and potentiodynamic polarization (PDP). Fourier transform infrared spectroscopy (FTIR) was utilized to give more insight into the functional groups that formed or disappeared during the adsorption/desorption of the studied quinoxaline molecules on the metal surfaces. …
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Evaluation of TiO2 as a Pt-Catalyst Support in a Direct Ethanol Fuel Cell
Direct ethanol fuel cells are of interest due to the high energy density, ease of distribution and handling, and low toxicity of ethanol. Difficulties lie in finding a catalyst that can completely oxidize ethanol and resist poisoning by intermediate reaction species. Degradation of the catalyst …
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SYNTHESIS AND CHARACTERIZATION OF NEW ELECTROCATALYTIC MATERIALS TO IMPROVE THE PERFORMANCE, OPERABILITY AND LIFE-TIME OF PEMFCS
… electrolyte fuel cell setup. Subsequently, the polarization curves obtained in the fuel cell are analyzed by means of a simplified model and important parameters about the catalytic layer are obtained. A comparative discussion of these results indicated the electrochemical performances of the …
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Comprobación de la eficacia de la realcalinización y de la extracción electroquímica de cloruros como métodos de rehabilitación de las estructuras corroídas de hormigón armado
… of assessing the steel corrosión rate, such as polarization resistance measurements, polarization curves, the response to short galvanostatic polarization pulses and the direct determination of the time constant of the corrosión process. All these techniques, applied before and after the …