Permselective Membrane
Mostrando 1-9 de 9 artigos, teses e dissertações.
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1. Parametric study of hydrogen production from ethanol steam reforming in a membrane microreactor
Microreactors are miniaturized chemical reaction systems, which contain reaction channels with characteristic dimensions in the range of 10-500 µm. One possible application for microreactors is the conversion of ethanol to hydrogen used in fuel cells to generate electricity. In this paper a rigorous isothermal, steady-state two-dimensional model was develop
Braz. J. Chem. Eng.. Publicado em: 2013-06
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2. Modelagem e simulação de um reator catalítico de membrana inerte permseletiva a hidrogênio com transferência de calor e massa / Modeling and simulation of a catalytic reactor with a permselective to hydrogen inert membrane with heat and mass transfer
Dentre os termoplásticos mais utilizados atualmente na indústria, pode-se mencionar o estireno, principal responsável pela produção de plásticos e borrachas. No processo de fabricação de estireno, a principal rota química é por meio da desidrogenação de etilbenzeno, com o hidrogênio como subproduto. A conversão de etilbenzeno nesta reação é
Publicado em: 2011
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3. Estudo da permeação de hidrogênio em reator com membrana de paládio: modelagem matemática e simulação computacional
Hydrogen is the simplest and most common element in the universe. Currently, some industries use hydrogen to refine oil, and to produce ammonia and methanol. Since the combustion of hydrogen produces only water and energy, it is considered to be viable and environmentally safe. Most of the hydrogen produced in industrial scale is by the steam reforming proce
Publicado em: 2009
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4. Modelagem e simulação da operação de um reator de leito fixo catalitico envolto em membrana permseletiva / Modeling and simulation of fixed bed reactor wrapped with permselective membranes
Styrene is an important monomer in the manufacture of thermoplastic and synthetic rubbers. Most of the production is based on the catalytic dehydrogenation of ethylbenzene. The increase of the styrene productivity can be reached using permselectives membranes for hydrogen removal, suppressing the reversible and secondary reactions. This work presents the sim
Publicado em: 2007
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5. Plant Cuticles Are Polyelectrolytes with Isoelectric Points around Three 1
The isoelectric points of isolated cuticles from Citrus aurantium L. (3.15), Prunus armeniaca L. (3.45), and Pyrus communis L. (2.90) leaves were determined from membrane potentials. At pH values below the isoelectric point, cuticular membranes carry a net positive charge and are permselective to anions (determined using 82Br−). Above the isoelectric point
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6. Abnormal apical cell membrane in cystic fibrosis respiratory epithelium. An in vitro electrophysiologic analysis.
The transepithelial chloride permeability of airway and sweat ductal epithelium has been reported to be decreased in patients with cystic fibrosis (CF). In the present study, we investigated whether the airway epithelial defect was in the cell path by characterizing the relative ion permeabilities of the apical membrane of respiratory epithelial cells from C
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7. Xenotransplantation of canine, bovine, and porcine islets in diabetic rats without immunosuppression.
Permselective acrylic membranes were employed to prevent immune rejection of discordant islet xenografts isolated from various large animals. Canine, porcine, and bovine islets were seeded into tubular diffusion chambers and transplanted into the peritoneum of 27 nonimmunosuppressed streptozotocin-induced diabetic Lewis rats. Six recipients received islet gr
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8. Temperature dependence of the four ionic processes of spike electrogenesis in eel electroplaques.
Spike electrogenesis of eel electroplaques involves four ionic processes which are controlled by the membrane potential. A threshold depolarization causes normally closed Na permselective channels to open (Na-activation) and normally open K channels to close (K-inactivation). The Na channels then close (Na-inactivation), and as the spike is terminated, the K
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9. A pump-pore model for transmembrane transport of hydrophilic solutes.
Transmembrane transport of a hydrophilic solute is presumed to begin when hydrated ligand adheres in Velcro-like fashion to hydrated membrane surface. Asymmetric physical forces cause rolling movements of ligand over membrane surface until contact occurs with appropriate transport machinery, consisting of a pump (Pu) to which is tethered a ligand (Li)-specif