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101.
102.
Zuzana Pátíková 《Mathematica Slovaca》2010,60(2):223-236
We establish asymptotic formulas for nonoscillatory solutions of a special conditionally oscillatory half-linear second order
differential equation, which is seen as a perturbation of a general nonoscillatory half-linear differential equation
$
(r(t)\Phi (x'))' + c(t)\Phi (x) = 0,\Phi (x) = |x|^{p - 1} \operatorname{sgn} x,p > 1,
$
(r(t)\Phi (x'))' + c(t)\Phi (x) = 0,\Phi (x) = |x|^{p - 1} \operatorname{sgn} x,p > 1,
相似文献
103.
Joe Kileel Zuzana Kukelova Tomas Pajdla Bernd Sturmfels 《Foundations of Computational Mathematics》2018,18(4):1043-1071
The distortion varieties of a given projective variety are parametrized by duplicating coordinates and multiplying them with monomials. We study their degrees and defining equations. Exact formulas are obtained for the case of one-parameter distortions. These are based on Chow polytopes and Gröbner bases. Multi-parameter distortions are studied using tropical geometry. The motivation for distortion varieties comes from multi-view geometry in computer vision. Our theory furnishes a new framework for formulating and solving minimal problems for camera models with image distortion. 相似文献
104.
Marie Horká Oldřich Kubíček Anna Kubesoví Zuzana Kubíčková Kateřina Rosenbergová Karel Šlais 《Electrophoresis》2010,31(2):331-338
In virological practice, the pre‐concentration, purification and subsequent determination of the purity and concentration of the viruses from the cultural medium and/or from the real sample are required. The conventional techniques used today are equipment demanding, time‐consuming and laborious. In this study, the CIEF of influenza viruses with UV detection has been developed and subsequently used to test the purification of the virus from the biological samples. The equine and swine influenza viruses present in infected allantoic fluid of specific pathogen free embryonated chicken eggs were precipitated by using PEG 6000 and sodium chloride. The precipitated viruses were centrifuged at 14 000×g, and the impurities of different densities were removed by using the sucrose gradients. The efficiency of the virus purification technique was examined by the CIEF and compared to the results of real‐time PCR. The pIs of both influenza viruses were determined. Simultaneously, the CIEF was found to be a suitable method for the rapid testing of the efficiency of the virus purification. 相似文献
105.
The mixed dissociation constants of methotrexate — chemically (2S)-2-[(4-{[(2,4-diamino-7,8-dihydropteridin-6-yl)methyl] (methyl)amino}phenyl)formamido]pentanedioic acid
(the cas number 59-05-2) at various ionic strengths I of range 0.01–0.4, and at temperatures of 25°C and 37°C, were determined
with the use of two different multiwavelength and multivariate treatments of spectral data, SPECFIT32 and SQUAD(84) nonlinear
regression analyses and INDICES factor analysis according to a general rule of first, determining the number of components,
and then calculating the spectral responses and concentrations of the components. Concurrently, the experimental determination
of the thermodynamic dissociation constants was in agreement with its computational prediction of the PALLAS programme based
on knowledge of the chemical structures of the drug. The factor analysis in the INDICES programme predicts the correct number
of light-absorbing components when the data quality is high and the instrumental error is known. Three thermodynamic dissociation
constants were estimated by nonlinear regression of {pK
a
, I} data: for methotrexate pKa1T= 2.895(13), pKa2T= 4.410(14), pKa3T= 5.726(15) at 25°C and pKa1T= 3.089(15), pKa2T= 4.392(12), pKa3T= 5.585(11) at 37°C, where the figure in brackets is the standard deviation in last significant digits. The reliability of
the dissociation constants of the drug were proven by conducting goodness-of-fit tests of the multiwavelength spectrophotometric
pH-titration data.
相似文献
106.
107.
Zuzana Kü hn Uwe Rö sler 《Proceedings of the American Mathematical Society》1998,126(3):769-777
Lyapunov proved that the range of finite measures defined on the same -algebra is compact, and if each measure also is atomless, then the range is convex. Although both conclusions may fail for measures on different -algebras of the same set, they do hold if the -algebras are nested, which is exactly the setting of classical optimal stopping theory.
108.
Iva Blanáriková-HlobilováZuzana Kubánová Lubor Fišera Michal K CyranskiPiotr Salanski Janusz Jurczak Nada Prónayová 《Tetrahedron》2003,59(18):3333-3339
Chiral nitrones derived from l-valine react with methyl acrylate to afford the corresponding diastereomeric 3,5-disubstituted isoxazolidines. The dibenzylsubstituted nitrone gave also 3,4-disubstituted isoxazolidine in 4% yield, additionally. The stereoselectivity was dependent on the steric hindrance of the nitrone and reaction conditions. High pressure decreased the reaction time of the cycloadditions. The major products were found to have the C-3/C-6 erythro and C-3/C-5 trans relative configuration. The major cycloadduct undergoes N-O cleavage and deprotection to a chiral diaminodiol derivative. 相似文献
109.
Zuzana Benkova Andrzej J. Sadlej Roma E. Oakes Steven E. J. Bell 《Theoretical chemistry accounts》2005,113(4):238-247
Reduced–size polarized (ZmPolX) basis sets are developed for the second–row atoms X = Si, P, S, and Cl. The generation of these basis sets follows from a simple physical model of the polarization effect of the external electric field which leads to highly compact polarization functions to be added to the chosen initial basis set. The performance of the ZmPolX sets has been investigated in calculations of molecular dipole moments and polarizabilities. Only a small deterioration of the quality of the calculated molecular electric properties has been found. Simultaneously the size of the present reduced–size ZmPolX basis sets is about one-third smaller than that of the usual polarized (PolX) sets. This reduction considerably widens the range of applications of the ZmPolX sets in calculations of molecular dipole moments, dipole polarizabilities, and related properties. 相似文献
110.
Propositional fuzzy logics given by a combination of a continuous SBL t‐norm with finitely many idempotents and of an involutive negation are investigated. A characterization of continuous t‐norms which, in combination with different involutive negations, yield either isomorphic algebras or algebras with distinct and incomparable sets of propositional tautologies is presented. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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