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41.
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A set of N-substituted benzoperylene monoimide (BPI) fluorophores was synthesized and characterized structurally and photophysically. Condensation of benzo[ghi]perylene-1,2-dicarboxylic anhydride in the presence of "swallow tail" alkyl amines produced fluorophores that are soluble in a range of organic solvents, highly absorbing in the near-UV (ε(334) = 79,000 M(-1) cm(-1)), and fluorescent in the visible range. Photophysical behavior of the compounds was studied with steady-state and time-correlated single photon counting. The synthesized BPIs exhibit positive solvachromatic emission (λ(em) (hexane) = 469 nm; λ(em) (ethanol) = 550 nm) as a function of solvent polarity with little change in their excited-state lifetime (9.6-6.5 ns) and fluorescence quantum yield (0.27-0.44) over the polarity range studied. Solvachromatic shifts were analyzed using the Lippert-Mataga approach. In nonpolar hydrocarbon solvents evidence of dual emission from closely spaced (562 cm(-1)) S(1) and S(2) excited states is observed. Preliminary peak assignments for the anomalous S(2) emission are made. 相似文献
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Robert M. Manning 《Radiophysics and Quantum Electronics》1996,39(4):287-295
The applicability of the classical Rytov method in statistical wave propagation problems is reconsidered and expanded by demanding results that are of second order in the permittivity fluctuations, rather than limiting them to just the first Rytov perturbation approximation, as is traditionally done. It is shown that one must augment the well-known second order statistics (e.g., log-amplitude variance), as calculated from the first Rytov approximation, with first-order statistics (e.g., the average log-amplitude), as calculated from the second Rytov approximation. Thus, a complete solution is derived for the second Rytov approximation for general beam wave propagation through turbulent media, the permittivity fluctuations of which are described by the Kolmogorov-Obukhov spectrum. This then allows a complete and consistent treatment that yields the fact that the average log-amplitude is, in the general beam wave case, not equal to the additive inverse of the log-amplitude variance. This gives results from the Rytov method that are then in exact agreement with the corresponding limiting case of strong fluctuation theory, as well as a simplified analytical expression for beam wave broadening, and the correct theoretical explanation of the well-known applicability limit for the Rytov method. 相似文献
45.
Tom Wagner Elisa Lopez‐Capel David Manning 《Rapid communications in mass spectrometry : RCM》2008,22(11):1625-1625
46.
M. M. Hicks-Bruun J. H. Bruun A. B. Manning F. M. E. Shepherd und F. Laupichler 《Fresenius' Journal of Analytical Chemistry》1933,95(1-3):101-102
Ohne Zusammenfassung 相似文献
47.
J. R. Manning 《The Journal of the Operational Research Society》1985,36(8):697-703
This is a case study of a project to introduce computer-aided scheduling into the stitching room of a shoe factory, which led instead to an automated microcomputer-controlled work-handling system. The outcome has been an increase in productivity and wages earned, together with a large reduction in throughput time and work-in-progress. 相似文献
48.
A.R. Manning Gerald McNally Reg Davis Christopher C. Rowland 《Journal of organometallic chemistry》1983,259(2):C15-C16
Depending on the substrate and the reaction conditions, SO2Cl2 is a useful reagent which brings about either chlorination or the formation of cationic species on reaction with transition metal carbonyl complexes. 相似文献
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