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151.
L. C. Fang D. Nicolaou J. W. Cleaver 《International Journal of Heat and Fluid Flow》1999,20(6):5512-613
A numerical and experimental study of the time-dependent hydrodynamic removal of a contaminated fluid from a cavity on the floor of a duct is presented. The duct flow has a parabolic inlet velocity profile and laminar flows are considered in a Reynolds number range between 50 and 1600 based on the duct height. The properties of the contaminated cavity fluid are assumed to be the same as for the fluid flowing in the duct. Attention is focussed on the convective transport of contaminated fluid out from the cavity and the effect of duct flow acceleration on the cleaning process. Passive markers which are convected with the flow are used in the numerical simulation for the purpose of identifying the contaminated cavity fluid. It is shown that the cleansing of the cavity is more pronounced during the unsteady start-up of the duct flow and the rate of cleaning decreases as the flow reaches a steady state. The cleaning process is enhanced as the cavity aspect ratio is increased and as the duct Reynolds number increases. A ‘volumetric’ approach based on the spread of markers is shown to be useful in determining the fraction of the cavity that remains contaminated after steady conditions have been reached. The distribution of the contaminant in a cavity during the unsteady stage and after steady conditions are reached are identified using passive markers. 相似文献
152.
K. C. Nicolaou Jim Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2001,113(22):4394-4398
153.
K. C. Nicolaou Frank Roschangar Dionisios Vourloumis 《Angewandte Chemie (International ed. in English)》1998,37(15):2014-2045
Only a few months after the disclosure of the absolute configuration of epothilones A (R=H, see picture on the right) and B (R=Me) the first total syntheses of these natural products were reported. Interest intensified with the realization of their potential as anticancer agents with a taxol-like mechanism of action. In addition to describing the most important total syntheses and biological properties of the naturally occurring epothilones A–E, this review also provides a systematic overview of numerous epothilone analogues that have been modified in the A – D regions in order to obtain information about structure–activity relationships. 相似文献
154.
Anna Nicolaou 《Annals of the Institute of Statistical Mathematics》1994,46(1):21-28
Consider the construction of an interval estimate for a scalar parameter of interest in the presence of orthogonal nuisance parameters. A conditional prior density on the parameter of interest that is proportional to the square root of its information element, generates one-sided Bayes intervals that are approximately confidence intervals as well, having coverage error of orderO(1/n), wheren is the sample size. We show that the frequency property of these intervals also holds conditionally on a locally ancillary statistic near the true parameter value. 相似文献
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