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41.
Bonner BE Buchanan JA Clement JM Corcoran MD Krishna NM Kruk JW Miettinen HE Moss RM Mutchler GS Nessi-Tedaldi F Nessi M Phillips GC Roberts JB Stevenson PM Tonse SR Birman A Chung SU Etkin A Fernow RC Kirk H Protopopescu SD Willutzki H Hallman T Madansky L Bar-Yam Z Dowd J Kern W King E Mayes BW Pinsky LS 《Physical review D: Particles and fields》1990,41(1):13-16
42.
We introduce a class of optimization problems, calleddynamic location problems, involving the processing of requests that occur sequentially at the nodes of a graphG. This leads to the definition of a new parameter of graphs, called the window indexWX(G), that measures how large a window into the future is needed to solve every instance of the dynamic location problem onG optimally on-line. We completely characterize this parameter:WX(G)k if and only ifG is a weak retract of a product of complete graphs of size at mostk. As a byproduct, we obtain two (polynomially recognizable) structural characterizations of such graphs, extending a result of Bandelt. 相似文献
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The feasibility of determining aqueous ozone by chemiluminescence flow-injection analysis (CL-FIA) was studied for applications in potable water treatment. The ozonated water sample is injected into a pure water carrier and mixed with a dye reagent in front of a photodetector. Many reagents undergo fast CL reactions with aqueous ozone. Most of these reactions display considerable selectivity for ozone over other oxidants of importance in water treatment. Even when there is steady-state response to another oxidant, significant discrimination against the interferents is possible by taking advantage of the much faster kinetics of the CL reaction with ozone. A simple design of a Siemens-type ozone generator and preparation of standard ozone solutions are also described. 相似文献
47.
Application of the refined Wiener-Hermite expansion with moderate to high Reynolds numbers Re to homogeneous, isotropic turbulence is presented. The results show a defect to Kolmogorov's five-thirds law, increase in the absolute value of the exponent comparable with many theoretical predictions. Midrange spectra up to fluctuation Reynolds numbers of 108 show little, if any, dependence of the defect on Re, as long as the initial spectra do not deviate too far from their equilibrium states. The renormalization scheme has also been proven to have no effect on the final shape of the spectrum. 相似文献
48.
Bonner BE Buchanan JA Clement JM Corcoran MD Krishna NM Kruk JW Lincoln DW Miettinen HE Mutchler GS Nessi-Tedaldi F Nessi M Phillips GC Roberts JB Stevenson PM Tonse SR White JL Chung SU Etkin A Fernow RC Protopopescu SD Willutzki H Hallman T Madansky L Pinsky LS 《Physical review letters》1989,62(14):1591-1594
49.
Strong, low-energy two-photon absorption in extended amine-terminated cyano-substituted phenylenevinylene oligomers 总被引:8,自引:0,他引:8
Chung SJ Rumi M Alain V Barlow S Perry JW Marder SR 《Journal of the American Chemical Society》2005,127(31):10844-10845
Three quadrupolar oligophenylenevinylenes with five rings in the conjugated backbone, terminal donor groups, and various acceptors and/or donors along the backbone were synthesized and their two-photon spectroscopic properties investigated. These chromophores exhibit large two-photon absorption cross sections over a wide wavelength range and two distinct peaks, the strongest of which (deltamax > 3600 GM) is observed at 960-970 nm, a wavelength close to twice the value of the linear absorption maximum (2lambda(1)max). The findings on these chromophores are compared with those for analogous molecules with shorter conjugation length, for which the main two-photon band is at significantly shorter wavelength than 2lambda(1)max. 相似文献
50.
E. W. Chung E. N. M. Ho D. K. K. Leung F. P. W. Tang K. C. H. Yiu T. S. M. Wan 《Chromatographia》2004,59(1):S29-S38
This paper describes a convenient method for the extraction and detection of eight anti-ulcer drugs simultaneously in horse urine, a relatively complex and viscous matrix, using a single-step liquid-liquid extraction followed by high-performance liquid chromatography – mass spectrometry (LC-MS). Anti-ulcer drugs were isolated from horse urine by salting out and liquid-liquid extraction. Detection of these drugs at concentrations below 1 ng mL?1 could be achieved using LC-MS-MS in the positive atmospheric pressure chemical ionisation (APCI) mode. The above analysis was also extended to elimination studies of horses administered with ranitidine and omeprazole. The urinary elimination data of these two drugs suggest that ranitidine was eliminated from horse urine at a much slower rate than omeprazole. In addition, three ranitidine metabolites and six omeprazole metabolites were identified for the first time in equine urine samples. 相似文献