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Christopher J. Orme John R. Klaehn Mason K. Harrup Thomas A. Luther Eric S. Peterson Frederick F. Stewart 《Journal of membrane science》2006,280(1-2):175-184
The synthesis, characterization, and gas permeability of 10 new polyphosphazenes has been studied. Additionally, the first gas permeation data has been collected on hydrolytically unstable poly[bis-(chloro)phosphazene]. Gases used in this study include CO2, CH4, O2, N2, H2, and Ar. CO2 was the most permeable gas through any of the phosphazenes and a direct correlation between the Tg of the polymer and CO2 transport was noted with permeability increasing with decreasing polymer Tg. To a lesser degree, permeability of all the other gases studied also yielded increases with decreasing polymer Tg. The trend observed for these new polymers was further supported by published data for other phosphazenes. Furthermore, permeability data for all gases were found to correlate to the gas condensability and the gas critical pressures, except for hydrogen, suggesting that the nature of the gas is also a significant factor for permeation through rubbery phosphazene membranes. Ideal separation factors () for the CO2/H2 and CO2/CH4 gas pairs were calculated. For CO2/CH4, no increase in was observed with decreasing Tg, however increases in were noted for the CO2/H2 pair. 相似文献
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Mason K. Harrup Michael G. Jones Linda Polson Byron White 《Journal of Sol-Gel Science and Technology》2008,47(3):243-251
Investigations were performed into the suitability of novel composites to serve as materials for subsurface permeable reactive
barriers (PRBs). These new materials are Type I composites—they are preformed organic polymers embedded in an inorganic matrix
without significant covalent bonding between the components. The required properties for these materials to function efficiently
are: (1) a tunable water passing rate to approximate the hydraulic conductivity of the subsurface environment where the PRB
will be placed, (2) sufficient mechanical strength (both wet and dry) to maintain barrier integrity, (3) the ability to incorporate
selective metal sequestration agents so that they remain active—yet do not leach from the barrier, and (4) to be deployable
through direct injection methods such that trenching is not needed. Additionally, there is a need to keep the technology as
low cost as possible, while remaining reliable. Results recently obtained in our laboratory show that our materials, remarkably,
exhibit all of these properties and show great promise as vadose zone deployable PRBs. 相似文献
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Dean R. Peterman Leigh R. Martin John R. Klaehn Mason K. Harrup Mitchell R. Greenhalgh Thomas A. Luther 《Journal of Radioanalytical and Nuclear Chemistry》2009,282(2):527-531
A new extractant for the separation of actinide(III) and lanthanide(III) cations, bis(o-trifluoromethylphenyl) phosphinic acid (2) was synthesized. The synthetic route employed mirrors one that was employed to produce the sulfur containing analog bis(o-trifluoromethylphenyl) dithiophosphinic acid (1). Classic radiochemical methods and absorbance spectroscopy were used to study the coordination chemistry of the Am-dithiophosphinic
acid and Am-phosphinic acid complexes. 相似文献
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González-Rivera Carlos Harrup Anthony Aguilar Carla Amaro-Villeda Adrián M. Ramírez-Argáez Marco A. 《Journal of Thermal Analysis and Calorimetry》2020,140(4):1825-1836
Journal of Thermal Analysis and Calorimetry - In this work, a new computer-aided cooling curve analysis method (CA-CCA) called metal/mold energy balance method (MEB) is presented. Its originality... 相似文献
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John R. Klaehn Thomas A. Luther Mason K. Harrup Frederick F. Stewart 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1587-1603
One approach to the synthesis of polyphosphazenes is the condensation polymerization of phosphoranimines. In this work, several novel P-n-propyl-N-trimethylsilylphosphoranimines have been synthesized and characterized. Modifications to the literature synthetic routes were required to obtain the precursor phosphines. The N-trimethylsilylphosphoranimines were obtained though oxidation of the phosphine with bromine and then subsequent nucleophilic displacement using lithium phenoxide. These phosphoranimines were stable for long periods of time under dry inert conditions. NMR analyses revealed complex splitting patterns beyond typical coupling due to the stereocenter at phosphorus. We report several approaches to the n-propyl containing phosphines and phosphoranimines. 相似文献
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