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51.
The results of fluorescence lifetime measurements using a dye laser excitation source are combined with other recently published data to present a consistent picture of the photophysics of the B? 1A1 state of Cl2CS. 相似文献
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J. A. Hermann J. N. Elgin P. L. Knight 《Zeitschrift für Physik B Condensed Matter》1982,45(3):255-258
We show that bistable behaviour in a two-photon resonant system within a cavity may be attributed to interactive mode-pulling via the two-photon optical Kerr effect and also to absorptive bleaching (atomic saturation). The interactive Kerr process may be regarded as giving rise to a new category of optical bistability. Moreover, a mechanism for the recently-predicted tristability can be found in terms of simultaneous competition between the interactive Kerr effect and bleaching. 相似文献
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A manual method was developed for scheduling the vehicle fleet of a contract transport undertaking. The main requirements were observance of time limits on individual calls and the ability to allocate pairs or groups of related calls to the same vehicle. These objectives were achieved by introducing an initial allocation of calls to vehicles prior to sequential routing of the calls. The allocation was based on a model relating work density (calls per unit area) to vehicle loading (calls per unit of vehicle time), and on fact-finding research on the main parameters of calling time, travelling speed and distance. This relationship was embodied in a visual scheduling aid for use by the route planners. Implementation was successful and resulted in about 15 per cent of vehicle time being made available for additional revenue-earning work without increase in fleet size. When utilized this represented an effective saving in operating costs of about 12 per cent. 相似文献
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Julia F. Knight 《Israel Journal of Mathematics》1982,42(1-2):151-161
Buechler proved that ifT satisfies certain conditions, then all resplendent models ofT are homogeneous. Here the theories whose resplendent models are all homogeneous are characterized as satisfying a pair of
conditions (weaker than Buechler’s). It follows from the characterization that if all resplendent models ofT in some uncountable power are homogeneous, then all resplendent models ofT are homogeneous.
The author thanks John Baldwin and the other participants in the 1979 and 1980 Forking Festivals for helping her to learn
some stability, and especially, Steve Buechler, whose results led directly to the results of this paper. Research partially
supported by the National Science Foundation under Grant MCS78-02224. 相似文献
60.
Citral (I) is cyclized by UV irradiation1 to 2-isopropenyl-5-methylcyclopentane-carboxaldehyde (II), containing the carbon skeleton of the monoterpenes of ants and catmint. 1,6,6-Trimethylbicyclo[2,1,1]hexane-2-carboxaldehyde (XII, R = H), produced in lesser amount at the same time, was synthesized from camphor. The two photocitrals may, perhaps, come from a common intermediate containing the cyclopentane ring. 相似文献