Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 256 for “"PEM"”.
-
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 …
-
Anodenkatalysatoren für PEM-Brennstoffzellen aus kolloidalen Vorstufen
… Further, the production of anode catalysts for PEM fuel cells by using this colloidal precursers and their characterization is content of this work, too. The XRD and XAS-measurements of the colloidal particles structure indicates a core-shell-structure for both, the Al-organic reduced and the …
-
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 …
-
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 …
-
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 …
-
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 …
-
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 …
-
PEM-fuel cell catalysts from nanoscopic precursors : a comparative study
1. Minimising the amount of stabiliser In an systematic study it was found that the amount of applied (Octyl)4N-protecting agent can be reduced to 60% from the amount usually applied for the preparation of Pt/Ru organosol using a combination of (Octyl)4N[Bet3H] and Li[Bet3H] as reductants. Further, …
-
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 …
-
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 …
-
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 …
-
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 …
-
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 …
-
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 …
-
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 …
Page 1 of 13