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Showing 1 to 20 of 47 for “"Gas Permeation"”.
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A study of poly(propylene) by gas permeation.
Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1968.
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Study of vapor/gas permeation using thin immobilized liquid membrane
… and stability for removal of vapor and gases from a gas stream, a thin immobilized liquid membrane (ILM) has been studied. Low vapor pressure liquid solvent/solutions were immobilized in part of the micropores of a hydrophilic, hydrophobic or ceramic hollow fiber substrate. To prepare …
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Gas permeation properties and characterization of mitrimid based carbon tubular membrane
Carbon membranes offer high potential in gas separation industry due to its highly selective. Therefore, this study aims to investigate the effect of carbonization parameter such as polymer composition, carbonization temperature, and carbonization environment on the gas separation properties. …
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Development and gas permeation study of flat asymmetric polyphenylene oxide membranes.
Natural gas is a mixture of hydrocarbon gases and impurities. Processing is required to recover valuable hydrocarbon liquids, remove water vapor, and increase the heating value of the gas before it can be sold to consumers. In addition, the removal of acid gases such as hydrogen sulfide and carbon …
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Microscopic description of gas permeation and delivery pathways in biological macromolecules
… substrate delivery and product removal. Since gaseous molecules such as O2, NO, CO2 and NH3 have tiny volumes, probing their interactions with their surroundings within a medium requires techniques that provide both atomic spatial and small temporal resolutions. To fulfill these purposes, I …
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Fabrication and Gas Permeation Studies on Polyimide/Layered-Aluminum Phosphate Nanocomposite Membranes
… The objective of this study was to examine if gas separation performance could be improved by introducing a layered nanopourous aluminum phosphate with a large aspect ratio into a polymeric matrix. The aluminum phosphate has eight membered rings, which could potentially serve as a size …
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Development of and gas permeation study of homo and copolymers from the family of polyphenylene oxides
Membrane gas separation emerged as a commercial process on a large scale during the 1980s. When compared to other gas separation processes such as cryogenics, adsorption and absorption, membrane separation competes primarily on the basis of overall economics and convenience, but not on the basis of …
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Physical and Gas Permeation Properties of a Series of Novel Hybrid Inorganic-Organic Composites Based on a Synthesized Fluorinated Polyimide
… with 3-aminopropyltriethoxysilane. The gas permeability, diffusivity, and selectivity were evaluated for He, O2, N2, CH4, and CO2, while the physical properties of these hybrid materials were evaluated using several analytical techniques. The results from this study revealed that gas …
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Remoção de CO2 do biogás por permeação em membranas
Biogas consists of a mixture of gases, composed mainly of methane (CH4 ) and carbon dioxide (CO2 ). Among the alternatives to reuse it, purification for injection into the natural gas grid is the most interesting option from an economical point of view. Biogas purification requires the removal of …
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Mixed Gas Transport Study Through Polymeric Membranes: A Novel Technique
The gas transport and separation properties of polymers have been successfully exploited in commercial ventures. Industrial applications employing membrane processes range from production of pure gases to barrier coatings for protection against environmental elements. Membrane separations are …
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Plasma-Material Interactions: A Langmuir Probe Analysis of a Cylindrical SiO(2) Deposition System and a Computational Study Using VFTRIM3D
… deposited in this system are analyzed for their gas permeation qualities and are correlated to the plasma properties gathered using Langmuir probes as well as the gas, pressure, and time recipes used to produce them. It is found in this work that the application of $\rm SiO\sb2$ films onto …
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ORMOCER (inorganic-organic hybrid polymer)-zeolite Nanocomposites: Advanced Membrane Materials for Gas Separation
… 29Si NMR, TG, DSC, SEM, N2 sorption and single-gas permeation measurements. The permeation performance of the membranes was examined using H2, He, CO2, O2 and N2 as a test gases at room temperature, the upstream pressure was varied between 1.3 to 2.5 atm. The effect of the amount of …
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Gas Separation Using Nanoporous Single-Layer Graphene Membranes
… as a highly promising membrane material for gas separation due to its atomic thickness. When single-layer graphene contains a high density of gas sieving nanoscale pores, it can exhibit both a high gas permeance and a high selectivity, which is beneficial for reducing the cost of gas …
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Water selective MFI zeolite membranes for application in the Fischer Tropsch Synthesis
… was evaluated using n-hexane porosimetry. Single gas and mixture separations were carried out. A trans-membrane pressure gradient was applied in single gas measurements. Binary and ternary mixture separations were carried out using a model reaction mixture that approximates FTS conditions. This …
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Partially-Fluorinated Polyimides using Aliphatic Diamines
… to address several of the existing problems with gas permeation membranes used today. These issues include the lack of flexibility and inverse ratio that exists between selectivity and permeation. The approach taken in order to solving the flexibility issue involved the incorporation of flexible …
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Production and characterisation of poly(vinyl chloride) (PVC) hollow fibre membranes for gas separation applications
… (PVC) hollow fibre membranes suitable for gas separation applications using the dry/wet phase inversion technique.The first part of this work involved the preparation of quaternary polymer solutions containing polyvinylchloride (PVC), dimethylacetamide (DMAc), tetrahydrofuran(THF) and …
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Estudo da difusão de hidrogênio em uma liga de alta entropia (CoCrFeNiMn) equimolar e nanocristalina
… Microscopy, Atomic Force Microscope, Hydrogen gas permeation and Thermal Desorption Spectroscopy. The alloy shows a single phase structure FCC, hardness average 170 HV, 376HV, 350 HV and 564 HV for annealed, cold rolling 50% and 70% and nanocrystalline respectively. For the first time was …
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Random Packs and Their Use in Modeling High Speed Porous Flow
… experiments of compressible, large Mach number gas permeation into packs of polydisperse spherical and non-spherical particles.
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Polymer/Clay Nanocomposites as Barrier Materials Used for VOC Removal
… of a tortuous pathway that will decrease gas permeation. The tortuous pathway is created by a nanoclay filler, whose ideal exfoliated structure has high surface area, and high aspect ratio. By choosing the appropriate surfactants, the nanoclays can be modified to allow improved molecular …
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