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Showing 1 to 20 of 26 for “"Molecular sieve"”.
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Polymer molecular sieve membranes
… design and fabrication of membranes from novel molecularly defined polymers and understanding their physical properties, particularly the transport properties of gas molecules in polymer membranes. First, we demonstrate a simple approach of fabricating novel polymer nanocomposite membranes using …
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Application of synthetic molecular sieve zeolites and silica gel towards the separation of sulfur dioxide from combustion gases
… desulfurization was performed. Linde Synthetic Molecular Sieves types 13X and AW500 and Davison Silica Gel were the materials studied. The motivation for this investigation was based on the premise that a suitable method for removing sulfur dioxide from combustion gas streams has not been …
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The use of novel mesoporous molecular sieve MCM-41 for the sorption and separation of neutral and overbased sulphonate and phenate lubricant detergents
An area of industry that exploits zeolites for separation purposes is that of the petroleum industry where zeolites are used in catalytic conversions as well as chromatographic separations of hydrocarbons. The development of large pore sized materials such as MCM-41 enables larger molecules to be …
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Design Method for Layered Bed Adsorber for Separation of CO2 and N2 from Natural Gas Using ZEOLITE13X, Carbon Molecular Sieve and Activated Carbon
… CO2 and N2 from NG using zeolite13X and a carbon molecular sieve (CMS3K) or activated carbon (ACB). These adsorbents are commercially available, and they offer easy and energy efficient regeneration for repeated uses. The product will meet the specified concentration limit for NG transmission and …
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The use of enzyme catalysts in organic media for the synthesis of biodegradable polyesters
… in anhydrous diethyl ether. Addition of molecular sieve to the above system gave higher molecular weight products. The PPL catalysed reaction of bis(2,2,2-trichlorethyl) adipate and glutarate with butane-1,4-diol in anhydrous ether with and without molecular sieve was investigated over a …
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Gas chromatographic determination of carbon dioxide, carbon monoxide, and nitric oxide in diesel exhaust
… a liquid phase column in series with a molecular sieve column, each of which eluted into thermal conductivity detectors, was utilized. Activation of the molecular sieve column was achieved by heat-treating and purging with nitric oxide. The chromatograph was calibrated by introducing …
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Binary gas adsorption on molecular sieves. Experimental data for the adsorption of oxygen, nitrogen and oxygen-nitrogen mixtures on five molecular sieve adsorbents at various temperatures and pressures and a comparison with theoretical models.
… mixtures on types 4A, 5A, 13X and Na-Mordenite molecular sieve pellets has been made. Pure component isotherms, using a volumetric apparatus, have been measured for each gas on each adsorbent at pressures up to 9 bar and for temperatures of 278.15,293.15 and 303.15 K. Curve fitting of the pure …
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Gas purification by short cycle pressure swing adsorption. Experimental and theoretical studies of a fixed bed adsorption process for the separation of carbon dioxide from air at ambient temperatures using molecular sieve 5A and activated charcoal adsorbents.
… air using both an activated carbon and a type 5A molecular sieve adsorbent. Continuous, cyclic operation was achievedusing a pair of fixed bed adsorbers. At any one time the feed gas entered one bed at a high pressure and part of the purified gas was returned to the other bed at a reduced pressure …
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Liquid-phase adsorption of n-paraffins on type 5A molecular sieves
… the adsorption of binary liquid mixtures of high molecular weight normal paraffins (C12, C16, and C20) from isooctane on type 5A molecular sieves. The literature relating to molecular sieve properties and applications, and to liquid-phase adsorption of high molecular weight normal paraffin …
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Fabrication and characterization of co-continuous elastomer-hydrogel composites
… composite can be used as a mechanically tunable molecular sieve in drug delivery and tissue engineering. Porous PEO-PDMS elastomer with interconnected microchannels is filled with polyacrylamide hydrogels via a microsphere-templating process. The configuration of the microstructure of the …
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The effects of heating and dehydration on the crystal structure of hemimorphite up to 600{u00B0}C
… Although hemimorphite may not qualify for a molecular sieve due to its small aperture size, it may be useful as an isotopic sieve.
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An experimental apparatus for the measurement of moisture permeability of building materials
… conditioning system using distilled water and molecular sieve desiccant humidifies or dries the chamber air as needed. The moisture transfer rate across the specimen is determined gravimetrically: the desiccant column is weighed to measure its change in mass as a result of moisture diffusion …
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Methanol conversion to olefins and propene oligomerization over modified SAPO-34 and dealuminated mordenite
… SAP0-34, a small-pore silicoaluminophosphate molecular sieve, is highly selective in the formation of ethene and propene from methanol, but deactivates rapidly due to coke formation. This catalyst was synthesized and modified in various ways in an attempt to increase the catalyst lifetime and …
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ORMOCER (inorganic-organic hybrid polymer)-zeolite Nanocomposites: Advanced Membrane Materials for Gas Separation
… membranes. Such mixed matrix membranes comprise molecular sieve entities integrated in ORMOCER® matrix. Mixed matrix membranes have the potential to combine the processability of ORMOCER® materials with the superior transport and ion exchange properties of molecular sieves. The versatility of …
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Síntesis y reactividad de sulfamidatos cíclicos derivados de aminoácidos
… Luca's group, a methodology based on the use of molecular sieve is used to avoid undesired elimination reactions. This methodology allows obtaining a library of peptides containing different lanthionines in their structure. In order to broaden the applications of cyclic sulfamidates towards …
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Polypyrrole Modified with Macrocycles for the Detection of Aqueous Pollutants and Carbon Membranes for the Separation of Gases
… of 0.1 mol dm-3 Na2SO4, respectively. Carbon molecular sieve membranes (CMSMs) were employed for the separation of gases. CMSMs displayed selective permeation of CO2 over N2 by a factor of 24.7:1.0. Reduction in the permeability of the membrane was observed with aging. This was restored using …
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Investigating the adsorption and transport of water in MFI zeolite pores for water desalination
… which is capable of performing this type of molecular sieve separation. However, a lack of understanding of the mechanisms that govern transport within the zeolite pore network as well as an insufficient control of membrane synthesis has limited the performance of past zeolite-based …
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Molecular mechanisms of gating and selectivity in transport channels
… and a small distal pore. The CD is apparently a molecular sieve covering the channel, that optimizes loss of osmolytes during osmoadaptation. Diffusion theory and MD simulations are employed to explore the transport kinetics of Glu- and K+ as representative osmolytes. A role of a filter is …
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MANGANESE OXIDE AS A NEW CATHODE CATALYST IN MICROBIAL FUEL CELLS (MFCs)
… oxides with a cryptomelane-type octahedral molecular sieve (OMS-2) structure to replace platinum as a cathode catalyst in microbial fuel cells (MFCs). Undoped (ud-OSM-2) and three catalysts doped with cobalt (Co-OMS-2), copper (Cu-OMS-2), and cerium (Ce-OMS-2) to enhance their catalytic …
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Discovery and characterization of prions in Saccharomyces cerevisiae
… Prion-forming proteins create bistable molecular systems whose semi-stochastic switching between functional states increases phenotypic diversity within cell populations. My thesis work explores the idea that rather than being detrimental, prions may commonly act to their host's …
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