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Showing 1 to 20 of 243 for “"PEM"”.
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Distribution of NMHC ratios in the Pacific during PEM-West B and PEM-Tropics A
… (GTE), the Pacific Exploratory Missions (PEM) have collected numerous air samples of many regions of the troposphere. Data from PEM-West B (February 7 to March 15, 1994), and PEM-Tropics A (August 15 to October 5, 1996) have been used here to study non-methane hydrocarbon (NMHC) ratios and …
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Rapid screening of PEM FC cathode catalysts
… for proton exchange membrane fuel cell (PEMFC) is the lack of fast high-throughput testing methods. Fast screening techniques enable a large number of catalysts to be tested in a relatively short time under the same conditions.<br/><br/>This project was focused on developing systems for …
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Particalized Eggshell Membrane (PEM) for Biomedical Applications
… study was to produce novel particalized ESM (PEM) with enhanced bioactivities for focused applications on positive skin health. A novel top-down method was developed to produce the PEM from table eggs, in a submicron size range. PEM exhibited dose- and size-dependent antimicrobial activity …
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Understanding of Ammonia Transport In Pem Fuel Cells
… anode in Proton Exchange Membrane Fuel Cells (PEMFCs). Since NH3 is fed to the anode in a gas phase and transferred to the cathode, the effect of a contaminant is distributed through MEA and quite complicated. This study is focused on the investigation of mechanism of NH3 transport and the …
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Transients in Polymer Electrolyte Membrane (PEM) Fuel Cells
… has presented proton exchange membrane (PEM) fuel cells as a potential energy source. The use of PEM fuel cells for automotive and other transient applications, where there are rapid changes in load, presents a need for better understanding of transient behavior. In particular at low …
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Comparative analysis of Polymer Electrolyte Membrane (PEM) fuel cells
… the Polymer Electrolyte Membrane Fuel Cells (PEMFC) membranes owing to their extensive intrinsic chemical stability and super sulfonic acid strength which is core to the PEMFC proton conductivity. This thesis presents a deeper analysis into these PFSA ionomer membrane electrode assemblies …
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Investigation of Graphite Bipolar Plates for PEM Fuel Cell Performance
The largest cost in manufacturing PEM fuel cells for automotive applications is due to the bipolar plate. The current graphite material used for the bipolar plate is very brittle and difficult to machine to the rigorous specifications needed for fuel cell stacks. This paper introduces the …
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Polyelectrolyte multilayers (PEM) in micro / nanofluidics for novel BioMEMS platforms
… versatility of the polyelectrolyte multilayer (PEM) to fabricate a novel micro/nanofluidic device for patterning bacteria in BioMEMS. Nanofluidic channels offer new opportunities for advanced biomolecule manipulation and separation science because they provide unique capabilities such as …
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Investigation of Shorting by Penetration in Pem Fuel Cell Membranes
… shorting through the proton exchange membrane (PEM) is a form of early failure commonly found in PEM fuel cells. In order to improve the durability and thus the commercial potential for PEM fuel cells, this form of failure must be understood and mitigated. This research investigates whether …
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Free air breathing planar PEM fuel cell design for portable electronics
PEM fuel cell technology is an energy source that can provide several times more energy per unit volume then current lithium ion batteries. However, PEM fuel cells remain to be optimized in volume and mass to create a minimum size for integration into portable electronics. A planar fuel cell design …
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A Comparison of Two Air Compressors for PEM Fuel Cell Systems
Proton exchange membrane (PEM) fuel cells are considered one of the best potential alternative power sources for automobiles. For this application, high efficiency and high power density are required. Pressurizing the fuel cell system can give higher efficiency, higher power density and better …
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Σύνθεση, φυσικοχημικός και ηλεκτροχημικός χαρακτηρισμός ηλεκτροκαταλυτών για κυψελίδες καυσίμου υψηλής θερμοκρασίας pem
… (Polymer Electrolyte Membrane Fuel Cells, PEMFCs) έχουν προσελκύσει το έντονο ενδιαφέρον της επιστημονικής κοινότητας εξαιτίας των πολλών πλεονεκτημάτων που παρουσιάζουν. Αποτελούν μία ιδανική συσκευή παραγωγής ενέργειας για πολλές εφαρμογές (μέσα μεταφοράς, κινητές εφαρμογές παραγωγής …
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Modelling, simulation and performance evaluation: PEM fuel cells for high altitude UAS
… in the load demand. A proton exchange membrane (PEM) fuel cell is considered as a potential power source for high altitude UAS (unmanned aircraft systems) operations. At altitudes in excess of 10 km, very low atmospheric temperatures and pressures, and unexpected variations in the load demand put …
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Electrochemical Oxidation of Carbon Monoxide in Reformate Hydrogen for PEM Fuel Cells
… of proton exchange membrane fuel cells (PEMFC). Various techniques studied to remove CO from source or mitigate CO poisoning have met with limited success due to fuel loss or increases infrastructure requirements to meet the operating needs. We developed a twin cell electrochemical filter …
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Computational fluid dynamics modelling of PEM fuel cells to investigate transport limitations.
… polluting emissions. Proton Exchange Membrane (PEM) fuel cell has shown and demonstrated that potential to be a suitable alternative power source because of its simplicity of design, load following capabilities, efficiency, feasibility and quick start-up. Although having these splendid …
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Understanding and Controlling Wettability of Carbon Powders for PEM Fuel Cell Applications
… of polymer electrolyte membrane fuel cells (PEMFCs). As the CLs are composed of Pt nanoparticles supported on carbon powders, bound together with Nafion®, the main focus of this work was to understand and control the wettability of carbon materials for their use in PEMFCs. The droplet …
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Development of a semi–empirical reaction kinetic model for PEM fuel cells
In the drive to more sustainable energy production, polymer electrolyte fuel cells (PEFC) have been at the pinnacle of global research. One of the major drawbacks of PEFCs is therequirement for expensive noble metal catalysts (platinum and ruthenium). Furthermore 75% of the overpotential losses at …
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