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Showing 1 to 20 of 33 for “"polymer membrane"”.
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Catalyst Layer Design in Polymer Membrane Fuel Cells
One of the biggest obstacles to commercializing polymer electrolyte membrane fuel cells is the use of platinum as a catalyst. One way to overcome this obstacle is to replace platinum with non-platinum group metal (non-PGM) catalysts, particularly for the oxygen reduction reaction (ORR) in proton …
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TiO2-doped Ionic Polymer-Metal Composite Actuator
Ionic polymer metal composites (IPMCs) have received substantial attention in the past several years. IPMC actuators are capable of complex deformation in water and air and they are soft actuation materials with promising applications in wide range of fields, such as robotics and medical devices. …
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Rapid extraction of dissolved inorganic carbon from seawater and groundwater samples for radiocarbon dating
… of carbon dioxide by utilizing a gas-permeable polymer membrane contractor. The second subsystem traps, quantifies and stores the extracted gas using cryogenics. The extracted carbon dioxide is further processed for stable and radiocarbon isotope analysis at the National Ocean Sciences …
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An implantable device for localized drug delivery and sensing
… has been demonstrated previously from a polymeric microreservoir device. This dime-sized device contains small reservoirs loaded with drug and separated from the outside environment by a degradable polymer membrane. This device was modified to allow minimally invasive implantation with a …
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Rapid extraction of dissolved inorganic carbon from seawater and groundwater samples for radiocarbon dating
… of carbon dioxide by utilizing a gas-permeable polymer membrane contractor. The second subsystem traps, quantifies and stores the extracted gas using cryogenics. The extracted carbon dioxide is further processed for stable and radiocarbon isotope analysis at the National Ocean Sciences …
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Multiscale Tortuous Diffusion in Anion- and Cation-Exchange Membranes: Exploration of Counterions, Water Content, and Polymer Functionality
… is critical for improving ion conductivity in polymer electrolyte membranes (PEMs). Herein, we present comprehensive water transport measurements comparing anion-exchange membranes (AEMs) based on ammonium-functionalized poly(phenylene oxide) and cation-exchange membranes (CEMs) based on …
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Transient Model of Heat,Mass,and Charge transfer as well as Electrochemistry in the Cathode Catalyst Layer of a PEMFC
… the cathode catalyst layer of a proton exchange membrane fuel cell is presented. The catalyst layer structure can be described as a superposition of the polymer membrane, the backing layer, and some additional platinum particles. The model, which incorporates some of the features of the …
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Advanced characterization of transport and microstructural properties in membrane materials
Membranes are employed in a variety of sustainable water treatment and energy conversion technologies. Advancing membrane materials for new separations includes unraveling the complex structure-property relationships that govern water and salt transport in conjunction with scaling processing …
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Development, Analysis, and Comparison of Electromechanical Properties and Electrode Morphology of Ionic Polymer Metal Composites
… indispensable structures. Among these, the Ionic Polymer Metal Composites (IPMC), with their large bending deformation and relaxation characteristics at very low voltages are attractive as transducers in many areas of application. The actuation and sensing properties of IPMC have been sought after …
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Room Temperature Ionic Liquid (Rtil) Membranes For Bio-Methane Dehumidification
… be dehumidified to become useable. Typically membrane-based gas dehumidification uses hydrophilic polymer membrane materials, such as polydimethylsiloxane (PDMS) and cellulose acetate (CA). The main problems with polymer dehumidification membranes are methane loss and the susceptibility of …
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Layer-by-layer assembly of conducting membranes for photoelectrochemical cells
… arrays into an ion-conducting, ultrathin polymer membrane. The choice of LbL platform and the properties of the silicon surface control the film morphology, generating either a conformal coating around each wire or a bridging film across the top of the array. Multilayer transfer printing …
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Manufacture and Characterization of Ionic Polymer Transducers Employing Non-Precious Metal Electrodes
Ionic polymer membranes are commonly used in fuel cell power generation, water electrolysis and desalinization, chlorine generation, and other niche applications. Since the early 1990s ionic polymer membranes have also shown promise as distributed electromechanical actuators and sensors. The cost …
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The development of nanoporous metal membranes for analytical separartions
… TiO2 sensitised quartz glass slides and organic membrane-based substrates. With the addition of a microparticle template material, nanoporous metal films with both single and multi-layer, highly ordered arrays of sub-µm (hemi) spherical pores have also been depsited directly onto the surface of …
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Transport properties of anion exchange membranes for fuel cell applications
… technology for efficient energy conversions. Polymer membrane electrolytes used in the fuel cell devices should be highly conductive, chemically and mechanically stable under extreme operating conditions of temperature and humidity, and cost effective. Although proton exchange membranes (PEM), …
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The Engineering and Development of pH-Responsive Biopolymers for Drug Delivery Applications
… the structure of biocompatible pH responsive polymers and their interaction with the biological system in order to design more effective entities for biomedical applications. A systemic approach was used to study the structure and biological interaction of pH responsive biocompatible poly …
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Polymer molecular sieve membranes
… of seawater for clean water production. Membrane separation technology offers attractive energy-efficient and environmental-friendly solutions to these challenges. This PhD thesis is focused on design and fabrication of membranes from novel molecularly defined polymers and understanding …
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Formation, Characterization and Stability of Natural Antimicrobial-Cyclodextrin Complexes
… comparison proved that absorption into the PET polymer membrane did not occur.
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Thermodynamics of ionic liquid solvents in gas purification and exfoliation mechanisms: molecular dynamics simulation and Monte Carlo calculations
… and post-combustion condition using a novel IL + polymer membrane material. This work was inspired by recent experimental findings from the Bara group at UA. The new class of materials was generated by adding ionic liquid molecules to the backbone of polymers while using (pyromellitic dianhydride) …
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Effects of Electrode Surface Morphology on the Transduction of Ionic Polymer-Metal Composites
Ionic polymer-metal composites (IPMCs) are innovative smart materials that exhibit electromechanical and mechanoelectrical transduction (conversion of electrical input into mechanical deformation and vice versa). Due to low driving voltage (< 5 V) and ability to operate in aqueous environment, …
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Development and validation of a computational model for a proton exchange membrane fuel cell
… computational model for a proton exchange membrane fuel cell (PEMFC) is presented. The model accounts for species transport, electrochemical kinetics, energy transport, current distribution, water uptake and release within the polymer portion of the catalyst layers, and liquid water …
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