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Showing 1 to 20 of 29 for “"polarization resistance"”.
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Assessment of In-situ Corrosion Conditions at Nevada Mechanically Stabilized Earth Wall Sites: Using Electrochemical Soil Characteristics and Linear Polarization Resistance
… backfill characterization and linear polarization resistance (LPR) corrosion rate monitoring. Evaluation of electrochemical backfill characteristics has resulted in the discovery of six sites that fail current NDOT/ AASHTO MSE wall backfill requirements. The in-situ soil samples …
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Assessment of Commercial Corrosion Inhibiting Admixtures for Reinforced Concrete
… corrosion activity as indicated by linear polarization, and ancillary temperature, relative humidity, and chloride concentration documentation. Simulated pore solution specimens were analyzed on the basis of weight loss and surface area corroded as a function of chloride exposure. …
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Impedance spectroscopy response of aluminum-copper-silicon alloys
… Cu and Si additions and heat treatment on the polarization resistance, oxide-layer/double-layer capacitance, open circuit potential and breakdown potential of Al-Cu-Si alloys was evaluated. Electrochemical impedance spectroscopy and DC polarization techniques were combined with mechanical …
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Stability of double perovskite cathodes under high humidity for solid oxide fuel cells
… conditions for SOFCs and SOECs to determine the polarization resistance, stability and durability of the cathode materials.
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Corrosion And Wear Resistance Of Titanium- And Aluminum- Based Metal Matrix Composites Fabricated By Direct Metal Laser Deposition
… also analyzed for each composite. The corrosion resistance of the MMCs were compared by monitoring open circuit potential (OCP), polarization resistance (Rp) and potentiodynamic polarization in 0.5 M NaCl to simulate exposure to seawater. The Ti-MMCs demonstrated improvements in hardness between …
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Infiltrated composite electrodes for solid oxide fuel cells
… be improved. This corresponds to minimized resistances from SOFC components (composite electrodes and electrolyte). Stability of the generated power is another important issue. Degradation of SOFCs with time due to microstructural processes or chemical reactions that occur at operating …
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Stress corrosion cracking behavior of friction stir processed ultrafine grained light metal alloys
… base alloy. The significant increment in linear polarization resistance of UFG Al-Mg-Sc alloy has been attributed to modification in chemistry and grain refinement. The slow strain rate testing (SSRT) results indicated no stress corrosion susceptibility for FSP Al-Mg alloy. A critical grain size …
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Fabrication and Characterization of Freeze Tape Cast Anode Supported Solid Oxide Fuel Cells
… have also shown significant reductions in polarization resistances (Rp). A cell employing a Ni-YSZ delivery layer, Ni-YSZ functional layer (FL), YSZ electrolyte, and LSM cathode displayed Rp of 0.56, 0.29, and 0.16 cm2at 700, 750 and 800°C, respectively.</p> <p>Using freeze tape casting, …
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Development of measurement techniques for evaluation of inhibitors for controlling rebar corrosion in concrete
… of the corrosion mechanisms and evaluation of polarization resistance values for the different specimens. In both phases of this work, chloride concentration profiles as function of depth were determined. The half-cell potential measurements in complete immersion were found to give an average …
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Corrosion Behavior of Nuclear Waste Storage Canister Materials
… behavior was evaluated using potentiodynamic polarization tests, and the surface morphology was studied using optical microscopy and scanning electron microscopy. Potentiodynamic polarization tests were conducted in 1.0M NaNO3 + 0.1M NaOH and 1.0M NaNO3 + 0.1M NaOH + 0.02M NaReO4. Tests were …
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Corrosion Behaviors of Coated Aluminum Alloys in Simulated Corrosive Environment
… temperature variation were cycled for 7 days. Polarization techniques were used to study the corrosion mechanism and calculate the corrosion rate of coated specimens under simulated salt water. Microstructure of coated specimens were identified by using atomic force microscopy (AFM) and optical …
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Development and Evaluation of NI-P-PTFE Based Nano-Composite Coatings for Medical Devices
… in the corrosion test, open circuit potential, polarization resistance (Rp), corrosion current density (Icorr), and corrosion rate (CR) were obtained by measuring the open circuit potential and anodic, cathodic tafel plots of Ni-P-PTFE-ZrO2 and Ni-P-PTFE-ZrO2-TiO2 coatings to evaluate their …
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Tailoring Perovskite- and Fluorite-Type Oxides for Solid Oxide Fuel Cells (SOFCs)
… composite cathode showed an area specific polarization resistance of 2.4 and 1.9 Ω.cm2 at 700 ºC for oxygen reduction reaction in the air and wet air, respectively, and exhibited an activation energy of 1.2 eV in both atmospheres.
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Thermodynamic stability of perovskite and lanthanum nickelate-type cathode materials for solid oxide fuel cells
… in SOFCs that causes efficiency loss is the polarization resistance associated with the oxygen reduction reaction(ORR) at the cathodes. Hence, improving the cathode design will greatly enhance the overall performance of SOFCs. Lanthanum nickelate, La2NiO4+δ (LNO), is a mixed ionic and …
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Mechanical Properties and Electrochemical Durability of Solid Oxide Fuel Cells
… aged 1000 hours at 1000 oC in air with/without polarization and investigated using Electrochemical Impedance Spectroscopy (EIS), Scanning Electron Microscopy (SEM), Brunauer-Emmett-Teller (B.E.T.) method and X-ray Diffraction (XRD). The performance of the half cell SOFCs degraded after aging …
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Investigation and modeling of uranium polarization for the electrorefining of Scrap U-MO foils
… enriched uranium to increase the proliferation resistance at such reactors. Pyroprocessing has been selected to recover uranium from the scrap produced in the manufacture of this novel fuel type. Electrorefining, the main separation process of pyroprocessing, is modeled through a novel approach …
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Corrosion of steel in the marine splash-zone.
… rates tended to increase with exposure time. Polarization of scaled specimens in synthetic sea water revealed increased cathodic depolarization, anodic polarization and decreased dependence on oxygen concentrations to result, as exposure times increased. At open circuit potentials neither the …
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Wear and Corrosion Resistance Improvement of CoCrMo alloy by Tantalum Based Coatings
… the polyethylene liner and improve the corrosion resistance of the femoral head, which leads to an increase in the lifetime of the implants. Tantalum (Ta) has attracted much interest as a coating material for the femoral head due to its unique properties. Ta is biocompatible, highly …
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Understanding Liquid-Air Interface Corrosion of Steel in Simplified Liquid Nuclear Waste Solutions
… in the form of pits under potentiostatic polarization condition. Gas bubbles were often observed to collect on corrosion product in the meniscus after extensive LAI corrosion. Additionally, LAI corrosion initiated later than crevice corrosion in the presence of a crevice. The effect of …
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Fabrication and characterisation of nickel/yttria stabilised zirconia cermet anodes for solid oxide fuel cells
… the limiting thickness for a low polarisation resistance. Below a thickness of 12 μm, the polarisation resistance increased in an erratic manner as the reaction zone was reduced. Ni/YSZ cermet anodes consisting of 90 vol% Ni and 10 vol% YSZ were fabricated in order to create an anode with …
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