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981.
Kaczmarek K Walczak B de Jong S Vandeginste BG 《Journal of chemical information and computer sciences》2003,43(3):978-986
Automatic alignment (matching) of two-dimensional gel electrophoresis images is of primary interest in the field of proteomics. The proposed method of 2D gel image matching is based on fuzzy alignment of features, extracted from gels' images, and it allows both global and local interpolation of image grid, followed by brightness interpolation. Method performance is tested on simulated images and gel images available via the Internet databases. 相似文献
982.
983.
Zbigniew Leyk 《Numerische Mathematik》1986,49(1):39-53
Summary A method of a collocation type based onC
0-piecewise polynomial spaces is presented for a two-point boundary value problem of the second order. The method has an optimal order of convergence under smoothness requirements on the exact solution which are weaker than forC
1-collocation methods. If the differential operator is symmetric, a modification of this method leads to a symmetric system of linear equations. It is shown that if the collocation solution is a piecewise polynomial of degree not greater thanr, the method is stable and convergent with orderh
r
inH
1-norm. A similar symmetric modification forC
0-colloction-finite element method [7] is also obtained. Superconvergence at the nodes is established. 相似文献
984.
Zbigniew Kokosiński 《BIT Numerical Mathematics》1990,30(4):583-591
A hardware-oriented algorithm for generating permutations is presented that takes as a theoretic base an iterative decomposition of the symmetric groupS
n
into cosets. It generates permutations in a new order. Simple ranking and unranking algorithms are given. The construction of a permutation generator is proposed which contains a cellular permutation network as a main component. The application of the permutation generator for solving a class of combinatorial problems on parallel computers is suggested. 相似文献
985.
Zbigniew Raszewski 《Liquid crystals》1988,3(3):307-322
Six binary liquid-crystalline mixtures have been studied by means of dielectric, microscopic and refractometric measurements. Induced smectic phases appear for four of them. The effective values of the components p⊥ and p∥ of the dipole moment per one molecule of the mixtures have been calculated from values of e∥ and e⊥. It has been established that the heterocomplexes formed in the mixtures are weak so that they do not cause any changes in the distribution of molecular charges. The observed deviations from linearity of the dielectric constants of the mixtures are caused either by dissociation of the cyanomesogen dimers or by a non-additive behaviour of the mixture density. 相似文献
986.
In this paper we present two recent studies utilizing pressure tuning spectroscopy. In the first of these we use high pressure photoluminescence to characterize the large difference in luminescence efficiency at one atmosphere between [Ru(bpy)3]2+ and [Ru(bpy)2py2]2+ ions. The lower efficiency of the latter ion is due to dissipation of excitation energy by motion of the pyridines. The second study involves a combination of photo-and thermoluminescence of doped ZnS phosphors of technical importance. In the phosphor doped with CI and Cu+ we demonstrate that the donors are pinned to the conduction band and the acceptors to the valence band. We invoke the presence of “deep levels” to describe the behavior of the traps. In the phosphor doped with Mn+2 plus C1- and Cu+ a series of traps appeared as the pressure was increased. By comparison with ZnS doped only with Mn+2 it was possible to assign some of the traps to C1- and others to Mn+2. 相似文献
987.
988.
The unexpectedly small secondary alpha deuterium KIE in the 4-methoxybenzyl chloride-thiophenoxide ion reaction is attributed to the increased conjugation between the aryl group and the alpha carbon in the SN2 transition state. 相似文献
989.
The course of the reaction between copper(I) sulphide and copper(II) sulphate in SO2 at 710–785 K was studied by the TG method under isothermal and non-isothermal conditions, as well as by the DTA method, X-ray analysis and scanning electron microscopy. It was established that the reaction is essentially dependent upon the initial composition of the substrate mixture, Cu2SO2 and Cu2SO2 being the chief intermediates in the reaction. Copper(I) oxide appears as the permanent final product of the reaction of interest. The reaction network, with the intermediate stages depending on the initial compositions in the temperature range studied, has been demonstrated.
Zusammenfassung Der Verlauf der Reaktion von Kupfer(I)-sulfid mit Kupfer(II)-sulfat wurde in SO2 bei 710–785 K durch isotherme und nichtisotherme Thermogravimetrie sowie DTA, Röntgenanalyse und Scanning-Elektronenmikroskopie untersucht. Es wurde festgestellt, daß die Reaktion wesentlich von der Ausgangszusammensetzung des Substratgemisches abhängt, wobei Cu2SO2 und Cu2SO4 die vorherrschenden intermediären Produkte der Reaktion sind. Kupfer(I)-oxid tritt als Endprodukt auf. Der die intermediären, im untersuchten Temperaturbereich von der Ausgangszusammensetzung abhängigen Reaktionsschritte in sich einschließende Reaktionsverlauf wird dargelegt.
710–785 , , . , . Cu2SO2 Cu2SO4, . , .相似文献
990.
Zbigniew Szafraniec 《manuscripta mathematica》2003,110(2):159-169
Let and be analytic germs, let be a closed ball of small radius centred at the origin, and let . Let , where λ(p) is the Morse index at a critical point p of a Morse function which approximates g|W
z
. For F and g satisfying some natural assumptions, we shall show that there is a finite family of analytic germs θ
i
(z) such that for a generic regular value z.
Received: 8 May 2001 / Revised version: 16 May 2002 Published online: 24 January 2003
Supported by grant BW 5100-5-0256-9
Mathematics Subject Classification (2000): 14P15, 32B10 相似文献