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Murray Marshall 《代数通讯》2013,41(5):1239-1248
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Jaroslaw Drelich Bowen LiPatrick Bowen Jiann-Yang HwangOwen Mills Daniel Hoffman 《Applied Surface Science》2011,257(22):9435-9443
Vermiculite decorated with copper nanoparticles is a new antibacterial material that was prepared in this study through ion-exchange process and hydrogen reduction. The replacement of magnesium ions in interlayer structure was carried out using concentrated copper sulfate solutions at elevated temperature. Copper ions were reduced to elemental copper at 400-600 °C using hydrogen as the reducing agent. During the reduction process copper diffused primarily to vermiculite surface regions and formed copper nanoparticles with a broad range of sizes, from ∼1 to 400 nm. Strong adhesion of copper nanoparticles to the vermiculite carrier makes this hybrid very stable and durable. The new vermiculite-metallic copper hybrid material shows strong antibacterial activity against Staphylococcus aureus at 37 °C. Vermiculite is an inexpensive mineral that is very stable under a wide range of industrial and environmental conditions, and extensively used as filler in fireproof materials, plastics, paints and lightweight concrete, so the addition of copper as an antibacterial agent opens new avenues for the application of vermiculite in consumer products and other areas. 相似文献
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Stefano C. G. Biagini Vernon C. Gibson Matthew R. Giles Edward L. Marshall Michael North 《Journal of polymer science. Part A, Polymer chemistry》2008,46(24):7985-7995
The block and random copolymerization of a series of amino acid and amino ester functionalized norbornenes by ring‐opening metathesis polymerization (ROMP) induced by the well‐defined molybdenum [Mo(?N‐2,6‐iPr? C6H3)(?CHCMe2)Ph)(OCMe3)2] or ruthenium [Ru(PCy)2Cl2(?CHPh)] based initiators is described. The monomers are derived from the amino acids glycine, alanine, and isoleucine or the methyl esters of these amino acids and either endo‐ or exo‐norborn‐5‐ene‐2,3‐dicarboxylic anhydride. Enantiomerically pure monomers afforded optically active polymers, and the mechanism and kinetics of the copolymerizations are investigated. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7985–7995, 2008 相似文献
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Julia L. Rummel Amy M. McKenna Alan G. Marshall John R. Eyler David H. Powell 《Rapid communications in mass spectrometry : RCM》2010,24(6):784-790
Direct Analysis in Real Time (DART) is an ambient ionization technique for mass spectrometry that provides rapid and sensitive analyses with little or no sample preparation. DART has been reported primarily for mass analyzers of low to moderate resolving power such as quadrupole ion traps and time‐of‐flight (TOF) mass spectrometers. In the current work, a custom‐built DART source has been successfully coupled to two different Fourier transform ion cyclotron resonance (FT‐ICR) mass spectrometers for the first time. Comparison of spectra of the isobaric compounds, diisopropyl methylphosphonate and theophylline, acquired by 4.7 T FT‐ICR MS and TOF MS, demonstrates that the TOF resolving power can be insufficient for compositionally complex samples. 9.4 T FT‐ICR MS yielded the highest mass resolving power yet reported with DART ionization for 1,2‐benzanthracene and 9,10‐diphenylanthracene. Polycyclic aromatic hydrocarbons exhibit a spatial dependence in ionization mechanisms between the DART source and the mass spectrometer. The feasibility of analyzing a variety of samples was established with the introduction and analysis of food products and crude oil samples. DART FT‐ICR MS provides complex sample analysis that is rapid, highly selective and information‐rich, but limited to relatively low‐mass analytes. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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