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141.
142.
Sands M Haswell SJ Kelly SM Skelton V Morgan DO Styring P Warrington B 《Lab on a chip》2001,1(1):64-65
The paper describes the equilibrium dependant reaction for the formation of enamines in a microchemical system utilising electroosmotic flow (EOF) for fluid mobilisation. The authors have shown that the reaction can be carried out without the presence of a Lewis acid catalyst, in addition the enamine intermediate was synthesised at room temperature using mild solvent conditions. A 42% conversion of cyclohexanone into the enamine has been achieved to date. 相似文献
143.
Electronic structure calculations for YH3 within the local density approximation result in a metallic ground state with the bands at the Fermi energy overlapping by more than 1 eV, whereas a band gap of 2.8 eV is deduced from optical experiments. Here, we report the results of parameter-free GW calculations which predict a fundamental gap of 1 eV. When we take into account electric dipole matrix elements a large optical gap of almost 3 eV is obtained. A combination of photoemission and inverse photoemission spectroscopy could test the prediction of a small fundamental band gap. 相似文献
144.
Xue QZ Xue QK Kuwano S Sadowski JT Kelly KF Sakurai T Ohno T 《Physical review letters》2000,84(17):4015
145.
Zheng Chen Daniel R. Dreyer Zong‐quan Wu Kelly M. Wiggins Zhenhua Jiang Christopher W. Bielawski 《Journal of polymer science. Part A, Polymer chemistry》2011,49(6):1421-1426
The synthesis and characterization of a novel family of main‐chain carbazole‐containing polymers using copper‐catalyzed azide‐alkyne cycloaddition chemistry is reported. The reactions were performed under mild conditions using readily available copper catalysts and ligands, which afforded polymeric products with Mws up to 18 kDa. Using a range of techniques, the polymers were found to exhibit a glass transition temperature (Tg) of 85 °C, high thermal stability (Td = 274 °C), and high photoluminescent quantum efficiency (?f = 0.29; λem = 448 nm), which underscore their potential for use in organic light‐emitting diodes or other emissive devices, particularly where efficient blue emission is of value. The approach described offers practical advantages over other synthetic methods used to prepare main‐chain carbazole‐containing polymers, especially with regard to the lack of need for rigorously inert conditions and the absence of byproducts generated during the polymerization reaction. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
146.
Bin Liu Rupa S. ShettyKristofer K. Moffett Martha J. Kelly 《Tetrahedron letters》2011,52(14):1680-1684
An efficient synthesis of 1,3,5-trisubstituted benzenes via a sequential Pd-mediated carbon-sulfur, carbon-nitrogen, and carbon-carbon bond formation reactions is reported. Selective amidation and sulfonamidation reactions are accomplished via Pd-catalyzed reactions between aryl chlorides and an acetamide or a methanesulfonamide. 相似文献
147.
148.
Despotopulos John D. Kmak Kelly N. Shaughnessy Dawn A. 《Journal of Radioanalytical and Nuclear Chemistry》2018,318(2):985-989
Journal of Radioanalytical and Nuclear Chemistry - A new procedure has been developed for isolating no-carrier-added 197m,gHg from 20 to 25&;nbsp;MeV α-particle irradiations of high purity... 相似文献
149.
John R. Ebdon Barry J. Hunt Paul Joseph Christopher S. Konkel Dennis Price Kelly Pyrah T. Richard Hull G. John Milnes Stephen B. Hill Christopher I. Lindsay John McCluskey Ian Robinson 《Polymer Degradation and Stability》2000,70(3):425-436
Methyl methacrylate (MMA) has been free radically copolymerized, both in bulk and in solution, with diethyl(methacryloyloxymethyl)phosphonate (DEMMP), to give polymers which are significantly flame retarded when compared with PMMA, as indicated by the results of limiting oxygen index (LOI) measurements, UL 94 tests, and the results of cone calorimetric experiments. The physical and mechanical properties of the copolymers are similar to those of PMMA, except that the bulk copolymers are slightly crosslinked, and are better than those of PMMA flame retarded to a similar extent by some phosphate and phosphonate additives. Examination of the some of the gaseous products of pyrolysis and combustion, and of chars produced on burning, show that flame retardation occurs in the copolymers by both a condensed-phase and a vapour-phase mechanism. The condensed-phase mechanism is shown to involve generation of phosphorus acid species followed by reaction of these with MMA units giving rise to methacrylic acid units. The methacrylic acid units subsequently form anhydride links, which probably impede depolymerization of the remaining MMA sequences, resulting in evolution of less MMA (the major fuel when MMA-based polymers burn). By undergoing decarboxylation, leading to interchain cyclisation and, eventually, to aromaticisation, the anhydride units are probably also the principal precursors to char. 相似文献
150.