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61.
Daszkiewicz Andrzej Kraśkiewicz Witold Przebinda Tomasz 《Central European Journal of Mathematics》2005,3(3):430-474
We classify the homogeneous nilpotent orbits in certain Lie color algebras and specialize the results to the setting of a
real reductive dual pair.
For any member of a dual pair, we prove the bijectivity of the two Kostant-Sekiguchi maps by straightforward argument. For
a dual pair we determine the correspondence of the real orbits, the correspondence of the complex orbits and explain how these
two relations behave under the Kostant-Sekiguchi maps. In particular we prove that for a dual pair in the stable range there
is a Kostant-Sekiguchi map such that the conjecture formulated in [6] holds. We also show that the conjecture cannot be true
in general. 相似文献
62.
The problem of identification in fuzzy systems described by the use of fuzzy equation is considered. The identification method and its performance index is also presented. The formal procedure of the identification algorithm is illustrated by means of a numerical example. The possibility of using the proposed algorithm for the solution of a control problem is given as well. 相似文献
63.
Witold Mozgawa 《Rendiconti del Circolo Matematico di Palermo》1985,34(2):192-201
There is proved that the transgressed classes are invariant under holomorphically projective transformations of connections. 相似文献
64.
This paper deals with some problems of the control of fuzzy systems described by means of a relational equation of the type: Xκ + 1 = Uκ ° Xκ ° R. The basic aspects such as mutual identification and control, stabilization control, control with constraints, generation of control rules of a fuzzy logic controller, important from the theoretical and applicational point of view are discussed and illustrated by means of numerical examples. 相似文献
65.
A water-in-oil-in-water emulsion liquid membrane system is used to transport alkali metal and alkaline earth cations from an external alkaline aqueous source phase through an organic membrane containing a crown ether carboxylic acid and into the internal acidic aqueous phase of the emulsion droplet. The influence of varying the crown ether carboxylic acid structure upon the selectivity and efficiency of competitive metal ion transport is examined. 相似文献
66.
67.
The dithiolium perchlorates 3a and b were smoothly converted into the phosphonium perchlorates 4a and b by reaction with tributylphosphin. Their deprotonation with butyllithium generates the methylen-phosphoranes 7 (not isolates), from which the electron-rich olefines 9a-d are obtained by successive treatment with the Δ4-1,3,4-thiadiazolium perchlorates 5d and e such as triethylamine. The olefine synthesis can be performed too by the reverse way, that is by the reaction of the phosphonium salts 6a-c with the dithiolium salts 3a and b under authentic conditions. In this way the electron-rich olefines 9e-h are obtained. 相似文献
68.
Competitive permeation of alkali metal ions from an alkaline source phase into or through a toluene phase facilitated by the lipophilic crown ether carboxylic acid 2-(symdibenzo-16-crown-5-oxy)-decanoic acid is studied in liquid—liquid extraction, bulk liquid membrane transport, and emulsion liquid membrane transport. Most rapid transport was obtained in emulsion liquid membrane experiments. Some differences in selectivity orders for alkali metal permeation were observed for the three separation techniques. 相似文献
69.
Witold Świa̧tkowski 《Journal of Physics and Chemistry of Solids》1980,41(6):665-668
The rate of crystallization of vitreous selenium containing 2 at.% of iodine was studied by calorimetric method in the temperature range 60–90°C. The obtained results satisfy an equation of Avrami. It was found that the exponential parameter z in this equation decreases as the temperature of crystallization increases. It was assumed in the discussion that the parameter z does not depend on the number of all processes occurring during nucleation. It depends only on slowly occurring processes. The increase of temperature probably causes a decrease of the number of slow processes and thus the value of the parameter z is diminished.The activation energy of crystallization is equal to with the standard deviation . 相似文献
70.
Witold Missol Mieczysław Woch Janusz Szymanowski Lucjan Kubica 《Mikrochimica acta》1993,110(4-6):249-261
The importance of particle X-ray microanalysis for contemporary metallurgical research has been accentuated. Corrections in the formulae for the geometric modelling method and simplifications in the calculation procedure are introduced. Conditions for successful application of the peak to background ratio method were outlined. Besides these two methods related to isolated particles a new extrapolation method for matrix embedded particles is developed and comments to the particle weight fraction estimation method for the same kind of particles are given. 相似文献