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.
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Showing 1 to 5 of 5 for “"Heteropolyacids"”.
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Proton Exchange Membrane Fuel Cell Systems Based on Aromatic Hydrocarbon and Partially Fluorinated Disulfonated Poly(Arylene Ether) Copolymers
… stable copolymer membranes were blended with heteropolyacids producing nanocomposites which have potential in higher temperature fuel cell applications. Lastly, the basic PEM parameters such as water uptake, proton conductivity, and methanol permeabilities were controlled and presented as …
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Direct Polymerization Of Sulfonated Poly(arylene ether) Random Copolymers And Poly(imide)Sulfonated Poly(arylene ether) Segmented Copolymers: New Candidates For Proton Exchange Membrane Fuel Cell Material Systems
… also show a high degree of compatibility with heteropolyacids such as phosphotungstic acid. These inorganic compounds provide a promising mechanism for obtaining conductivity at temperatures well above the boiling point of water and membrane compositions containing them are being actively …
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Control of regioselectivity:oxidation and deprotection
… small-molecule reoxidants. However, the use of heteropolyacids is found to lead to a catalytic reaction. A second source of unexpected regioselectivity in the Wacker reaction is the agostic interaction of hydrogens on the allylic position with the palladium centre. Some new evidence is obtained …
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Synthesis and characterisation of proton conducting membranes for direct methanol fuel cell (DMFC) applications
For a direct methanol fuel cell (DMFC), the proton exchange membrane must conduct protons and be a good methanol barrier. In addition to the high methanol permeability achieved by these membranes, they are very expensive and contribute greatly to theoverall cost of fuel cell set up. The high cost …
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Catalisadores heterogêneos a base de heteropoliácidos e estanho para produção de biodiesel
A obtenção de biodiesel via reações de esterificação vem se tornando cada dia mais viável, pois existe uma grande quantidade de ácidos graxos livres presentes em rejeitos industriais, domésticos ou gorduras animais. Entretanto é necessária a busca por novos catalisadores que promovam as reações de …