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41.
Oscillatory properties of a weak convergent sequence of functions bounded inL
p
, 1 ≤p ≤ ∞, may be summarized by the parametrized measure it generates. When such a measure is generated by the gradients of a sequence
of functions bounded inH
1,p
, it must have special properties. The purpose of this paper is to characterize such parametrized measures as the ones that
obey Jensen’s inequality for all quasiconvex functions with the appropriate growth at infinity. We have found subtle differences
between the casesp < ∞ andp = ∞. A consequence is that any measure determined by biting convergence is in fact generated by a sequence convergent in
a stronger sense. We also give a few applications.
Research groupTransitions and Defects in Ordered Materials, funded by the NSF, the AFOSR, and the ARO. The work of the second author is also supported by DGICYT (Spain) through “Programa
de Perfeccionamiento y Movilidad del Personal Investigador” and through Grant PB90-0245. 相似文献
42.
43.
J. Rico B. Rubio J. L. Tain A. Gadea J. Bea L. M. Garcia-Raffi O. Tengblad P. Kleinheinz R. Menegazzo R. Wirowski P. von Brentano G. Siems J. Blomqvist 《Zeitschrift für Physik A Hadrons and Nuclei》1993,345(2):245-246
In a high sensitivity (,2n) in-beam study of
62
144
Sm82, with the Kölner Würfel OSIRIS -detector array including a Compton polarimeter, we have identified the complete two-proton multiplets d
5
2/–2
, d
5
2/–1
g
7
2/–1
, g
7
2/–2
, h11/2d
5
2/–1
and the 9– to 4– members of the h11·/2g
7
2/–1
multiplet.Work partially supported by CICYT (Spain). 相似文献
44.
An introduction to population approaches for optimization and hierarchical objective functions: A discussion on the role of tabu search 总被引:3,自引:0,他引:3
Pablo Moscato 《Annals of Operations Research》1993,41(2):85-121
Population approaches suitable for global combinatorial optimization are discussed in this paper. They are composed of a number of distinguishable individuals called "agents", each one using a particular optimization strategy. Periods of independent search follow phases on which the population is restarted from new configurations. Due to its intrinsic parallelism and the asynchronicity of the method, it is particularly suitable for parallel computers. Results on two test problems are presented in this paper. The individual search optimization strategies for each agent have been chosen having the basic characteristics of tabu search. This has been done in order to avoid mixing the hypothesized properties of these population approaches with those of more elaborate tabu search strategies, but remarking on its main characteristics. A set of four test problem "landscapes" is discussed and their use to improve and benchmark the results by using tabu search as the individual optimization strategy within a population heuristic is suggested and explored. The application of tabu search to new problem areas, like molecular biology, is also investigated. 相似文献
45.
46.
Liquid chromatography-hydride generation-inductively coupled plasma optical emission spectroscopy (LC-HG-ICP/OES) has been used to determine inorganic and organometallic species of germanium. In recent studies these coupled systems has been applied successfully to the speciation of arsenic. To establish separation conditions for germanium two reversed stationary phases and different solvent mixtures for elution, in isocratic or gradient mode have been tested. The reduction of germanium species to the corresponding volatile hydride is a critical step, especially for acidity control, thus the conditions for reduction using different concentrations of acid have been studied systematically. For the conditions established quality parameters as limit of detection (at the g l–1 level), precision and recovery have been determined for the germanium species considered in a saline matrix. 相似文献
47.
den Brok MW Nuijen B Miranda E Floriano P Munt S Manzanares I Beijnen JH 《Journal of chromatography. A》2003,1020(2):251-258
ES-285 x HCl [(2S,3R)-2-amino-3-octadecanol hydrochloride] is a novel investigational anticancer agent, which has shown in vitro and in vivo cytotoxic activity against various tumor cell lines with selectivity for certain solid tumors. The pharmaceutical development of ES-285 x HCl warranted the availability of an assay for the quantification and purity determination of ES-285 x HCl active pharmaceutical ingredient (API) and its pharmaceutical dosage form. A liquid chromatographic method (LC) comprising of derivatisation of ES-285 x HCl with phenylisothiocyanate and UV-detection was developed. The method was found to be linear, precise and accurate. The assay also proved selectivity as determined by analysing ES-285 x HCl in combination with 15 analogues and in combination with hydroxypropyl-beta-cyclodextrin, the excipient used in the lyophilised pharmaceutical dosage form. Stress testing showed that the degradation products were separated from the parent compound, confirming its stability indicating capacity. The method was found robust as determined with design of experiments (DoE), which made it possible to predict system suitability responses in worst case experimental conditions and to define criteria for system suitability testing. 相似文献
48.
Different transformations of chiral epoxy esters 1 afford two different amino gamma-butyrolactones 2 and 6, and amino gamma-butenolides 8, by different nucleophilic opening-closing processes. [reaction: see text] 相似文献
49.
A fluorimetric procedure for the determination of sulphate (0.5-6 mug ml ) based on the formation of a ternary complex with biacetylmonoxime nicotinylhydrazone and zirconium(IV) is described. The excitation and fluorescence maxima are at 415 and 505 nm, respectively. The method is rapid and the procedure reproducible. The precision is +/- 2% near to the middle range of the calibration curves. There is no interference from most common ions. Phosphate and fluoride are tolerated at 100-fold molar ratio to sulphate. The method has been applied to the determination of sulphate in a variety of water samples. 相似文献
50.
Mary E. R. McHale Ann-Sofi M. Kauppila Joyce R. Powell Pablo Otero Jr. Melani Jayasekera William E. Acree Jr. 《Journal of solution chemistry》1996,25(3):295-302
Experimental solubilities are reported for benzil dissolved in six binary mixtures containing dibutyl ether with hexane, heptane, octane, cyclohexane, methylcyclohexane, and 2,2,4-trimethylpentane at 25°C. Results of these measurements are compared to the predictions of equations developed previously for solubility in systems of nonspecific interactions. The most successful equation in terms of goodness of fit involved a volume fraction average of the excess Gibbs energies relative to the Flory-Huggins model, and predicted the experimental solubilities in the six systems studied to within an overall average absolute deviation of 3.4% and with a maximum deviation of 6.0%. 相似文献