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991.
Sylvain Hudlet Sbastien Aubert Aurlien Bruyant Renaud Bachelot Pierre-Michel Adam Jean-Louis Bijeon Gilles Lrondel Pascal Royer Andrei A. Stashkevich 《Optics Communications》2004,230(4-6):245-251
Apertureless scanning near field optical microscopy techniques have become a common way of studying surface samples. By using a nano-probe that scatters the electromagnetic non-propagative waves emerging from a given sample, this microscopy provides optical images with a resolution beyond the diffraction limit. Despite a great diversity of works covering a wide variety of physical domains, the formation of the images obtained is not yet fully understood. The purpose of this letter is to assess the influence of the tip position and imposed oscillation of the tip in apertureless SNOM when a background field is added to the scattered near field. We propose a simple analytical model which enables us to account for the experimental results and explains how, depending on the experimental conditions, the near field signal can totally disappear or, on the contrary, be greatly enhanced. 相似文献
992.
S. T. Adam 《Journal of separation science》1988,11(1):85-89
A commercially available mechanical micro switching valve has been tested for inertness. The test mixtures used were a modified Grob test and a solution consisting of eight typical aroma compounds, both at the 2-ng level. Cryogenic focusing of the sample after chromatography including one passage through the valve revealed that irreversible interaction of some test substances with valve components was rather small. A composite main peak of a chromatogram from a fruit juice aroma exhibiting a “mixed odor” was selectively transferred (heart-cutting) to a second column and resolved into three peaks. GC-GC/sniffing assigned a minor peak to a substance formerly hidden under the composite peak. Separate heating of the valve during temperature programming of the column was found to be unnecessary. 相似文献
993.
Adam Voelkel 《Journal of chromatography. A》1988,450(3):291-308
The polarities of oligooxyethylene derivatives of alcohols, thio alcohols and alkylamines were determined by gas chromatography. Relationships between empirical, thermodynamic and dispersive force polarity parameters are discussed. The influence of the structures of the compounds [lengths of oligooxyethylene and hydrocarbon chains, heteroatom linked to the alkyl group(s), distribution of carbon atoms in alkyl chains and the type of the group terminating the molecule] was examined. The average structural increments of the considered parameters for characteristic structural fragments were calculated and used in the prediction of the polarities of compounds from their formulae. 相似文献
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This paper provides a formal framework within which to study cooperative behavior in the presence of incomplete information, and shows how far the known results in the static cooperative game theory can readily be applied to the proposed framework. The new concepts of Bayesian society, Bayesian strong equilibrium and Bayesian incentive compatible strong equilibrium are introduced and studied. 相似文献
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F. Křížek V. Wagner J. Adam P. Čaloun V. Henzl D. Henzlová A. Krása A. Kugler M. Majerle M. I. Krivopustov V. I. Stegailov V. M. Tsoupko-Sitnikov 《Czechoslovak Journal of Physics》2006,56(3):243-252
The Neutron Activation Analysis Method was used to study neutron field in a setup consisting of a thick lead target and a
natural uranium blanket. This setup was exposed to 1.5 GeV proton beam from the Nuclotron accelerator. By means of gamma-ray
spectroscopic measurements we determined the yields of various nuclear reactions induced in the radio-chemical sensors. The
data obtained were then compared with the results of a MCNPX simulation. 相似文献