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Showing 1 to 15 of 15 for “"PFSA"”.
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An Investigation into the Use of Density Functional Theory (DFT) Calculations for Predicting Vibrational Transitions for Perfluroinated Sulfonic Acid (PFSA) Ionomer Membranes
Perfluorinated sulfonic acid (PFSA) ionomer membranes demonstrate great potential for use in proton exchange membrane fuel cells (PEMFCs) due to their favorable electronic properties and excellent efficiency. However, the assignment of key vibrational transitions such as the symmetric sulfonate and …
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Structure-Morphology-Property Relationships in Perfluorosulfonic Acid Ionomer Dispersions, Membranes, and Thin Films to Advance Hydrogen Fuel Cell Applications
… groups, called perflurosulfonic acid ionomers (PFSAs). The purpose of this dissertation is to investigate the effects of industrial processing parameters such as dispersion solvent composition, solvent evaporation temperature, and annealing temperature on fuel cell-relevant properties of PFSA …
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Influence of Sidechain Structure and Interactions on the Physical Properties of Perfluorinated Ionomers
… properties of perfluorosulfonic acid ionomer (PFSA) membranes. One of the primary objectives was to characterize the thermomechanical relaxations for short sidechain PFSAs developed by 3M and Solvay, as well as a new multi-acid sidechain perfluoroimide acid ionomer (PFIA) from 3M. Partial …
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Rational design of proton exchange membranes: perfluoro polymers with sulfonic acid and heteropoly acid functionalities
… in the field of perfluorinated sulfonic acid (PFSA) membranes is dictated by our understanding of pure PFSA ionomer materials like Nafion®, which performs well at saturated conditions but fails at low relative humidity and high operating temperatures (80-120 C). The motivation of this study is …
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Modelos Markovianos para sistemas dinâmicos empregando aprendizado de máquina e teoria de autômatos
… um Autômato Probabilístico de Estados Finitos (PFSA, Probabilistic Finite State Automata), comumente empregado em algoritmos de controle e técnicas de detecção de falha. Este trabalho apresenta um novo algoritmo para determinar um PFSA associado a um sistema dinâmico a partir de uma realização …
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Comparative analysis of Polymer Electrolyte Membrane (PEM) fuel cells
Per-Fluoro-Sulphonic-Acid (PFSA) ionomers have been singled out as the preferable ionomers for making 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. …
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Atmospheric Distribution and Seasonality of Airborne Polyfluorinated Compounds: Spatial and Temporal Concentration Variations from Ship-and Land-Based Measurements in Northern Germany, the Atlantic Ocean, and Polar Regions
… (PFCA) und Perfluorsulfonate (PFSA), sind persistent, bioakkumulativ und toxisch. Der atmosphärische Transport und Abbau von neutralen volatilen PFCA und PFSA Vorläufersubstanzen könnte die Existenz der persistenten perfluorierten Säuren in quellenfernen Gebieten erklären. …
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Development of novel catalysts coated non-fluorinated proton exchange membranes for water electrolysis
… the development of poly perfluorosulfonic acid (PFSA)-based membranes. These membranes offer high proton conductivity, exceptional chemical stability, and mechanical strength under vari-ous conditions, thanks to the strong C–F bonds in their molecular structure. However, PFSA mem-branes face …
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Synthesis and characterization of aminated perfluoro polymer electrolytes
… of a novel polymer electrolyte. The 800 EW 3M PFSA sulfonyl fluoride precursor was aminated with 3-(dimethylamino)-1-propylamine to yield a functional polymer electrolyte following quaternization, referred to in this work as PFSa-PTMa. 1 M solutions of LiPF6, HCL, KOH, NaOH, CsOH, NaHCO3 and …
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Nanoscale Liquid Dynamics in Membrane Matrices: Insights into Confinement, Molecular Interactions, and Hydration
… transport by experimental measurements on a PFSA membrane and computer modeling of the confined liquid molecules. We probe the nano-scale environment in the ionomer membrane by determining the activation energy of diffusion. We notice two structural features of the PFSA membrane that dominate …
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Photochemical processes in engineered aquatic systems for remediation of per- and polyfluoroalkyl substances and algae cultivation
… (e.g., long-chain perfluoroalkyl sulfonic acids (PFSAs) and perfluoroalkyl carboxylic acids (PFCAs)) were readily degraded, other structures (e.g., short-chain PFSAs and fluorotelomer sulfonic acids (FTSs)) were more recalcitrant. Furthermore, results show that PFSAs, PFCAs, and FTSs can form as …
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SYNTHESIS OF PERFLUOROHETEROAROMATIC POLYMERS FOR ION-CONDUCTING MEMBRANE FUEL CELLS VIA FREE RADICAL-BASED REACTIONS AND SYNTHESIS OF DI-CATIONIC IONIC LIQUIDS AS EFFICIENT SO2 ABSORBENTS
… compounds to perfluorosulfonic acid polymers (PFSAs). Two proton-exchange membranes perfluorobenzoic acid (PFBA) and perfluorobenzenesulfonic acid (PFBSA)—were synthesized for proton-exchange membrane fuel cells via the free radical-based reaction. The physical properties, in-plane ionic …
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Low PGM PtCo alloy catalysts for low loading Polymer Electrolyte Membrane Fuel Cells
… is combined with a perfluorosulfonic acid (PFSA) ionomer which serves as the proton conductor and binder to form the catalyst layer (CL). The ionomer contains both hydrophilic and hydrophobic groups, and therefore plays a key role in water management in the fuel cell. In every MEA design, …
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Remediation of per and polyfluoroalkyl substances by pilot-scale applications of advanced water treatment technologies
… longer chain PFASs and perfluorosulfonic acids (PFSAs) occurring later than shorter chain PFASs and perfluorocarboxylic acids (PFCAs), respectively. Greater adsorption capacity was found for GAC products containing high volumes of transport pores. A subsequent study compared a better performing …
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Evaluation of process parameters and membranes for SO2 electrolysis
… and sulphuric acid, using commercially available PFSA (perfluorosulfonic acid) (Nafion®) as benchmark by evaluating i) various operating parameters (such as cell temperature and membrane thickness), ii) the influence of MEA (membrane electrode assembly) manufacturing parameters (hot pressing time …