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Arno Jüschke Johannes Jahn Andreas Kirsch 《Computational Optimization and Applications》1997,7(3):261-276
In this paper we consider a special optimization problem withtwo objectives which arises in antenna theory. It is shown that thisabstract bicriterial optimization problem has at least one solution.Discretized versions of this problem are also discussed, and therelationships between these finite dimensional problems and the infinitedimensional problem are investigated. Moreover, we presentnumerical results for special parameters using a multiobjectiveoptimization method. 相似文献
4.
Editor's preface 总被引:1,自引:0,他引:1
Johannes Jahn 《Mathematical Methods of Operations Research》1991,35(3):I-I
5.
Contingent epiderivatives and set-valued optimization 总被引:24,自引:0,他引:24
In this paper we introduce the concept of the contingent epiderivative for a set-valued map which modifies a notion introduced by Aubin [2] as upper contingent derivative. It is shown that this kind of a derivative has important properties and is one possible generalization of directional derivatives in the single-valued convex case. For optimization problems with a set-valued objective function optimality conditions based on the concept of the contingent epiderivative are proved which are necessary and sufficient under suitable assumptions. 相似文献
6.
Jahn A Vreeland WN Gaitan M Locascio LE 《Journal of the American Chemical Society》2004,126(9):2674-2675
Traditional liposome preparation methods are based on mixing of bulk phases, leading to inhomogeneous chemical and/or mechanical conditions during formation; hence liposomes are often polydisperse in size and lamellarity. Here we show the formation of liposomes that encapsulate reagents in a continuous two-phase flow microfluidic network with precision control of size from 100 to 300 nm by manipulation of liquid flow rates. We demonstrate that by creating a solvent-aqueous interfacial region in a microfluidic format that is homogeneous and controllable on the length scale of a liposome, we can facilitate the fine control of liposome size and polydispersity. 相似文献
7.
Verardo G Pagani E Geatti P Martinuzzi P 《Analytical and bioanalytical chemistry》2003,376(5):659-667
The composition of the surface waxes of three apple ( Malus domestica L.) cultivars ("Florina", "Golden B" and "Ozark Gold") has been studied by means of spectroscopic and GC–MS analysis of the class-fractionated mixture of components. Odd n -alkanes, mainly C27 and C29 molecules, are prevalent in the saturated fraction. Small concentrations of alkenes were also found; the C28:1 component is strongly (72%) in excess over the other 1-alkenes. Straight-chain esters (mainly of palmitic acid) of saturated primary alcohols (C18–C30) were also detected; whereas the acyl moiety is made up essentially of an even number of carbons, the alcohol counterpart does not exhibit this characteristic. Aldehydes are present (C20–C30) with the homologue patterns C26–C30 most strongly represented. Straight-chain free secondary alcohols characterize the waxes of "Florina" and "Ozark Gold"; the hydroxy function is located far from the extremity of the carbon framework. Outstanding is the presence of three alcohols with 29 carbon centres. These alcohols are accompanied by free straight-chain primary alcohols, mainly with even-numbered carbon chains in the range C26–C30. Free fatty acids are present; all of have a framework of even-numbered carbon chains mainly in the range C16–C20. C18:1 (oleic acid) is well represented. 相似文献
8.
Gaetano Alberghina Maria Emanuela Amato Francesco Agatino Bottino Antonino Corsaro Salvatore Fisichella 《Journal of heterocyclic chemistry》1986,23(6):1747-1752
The 1H-nmr data of some (Z)-α-(p-substituted-phenyl)-β-(2-furyl), -(2-pyrrolyl), and -(N-methyl-2-pyrrolyl)-acrylonitriles have been investigated to indicate the preferred conformation and to establish the conformational preferences of the β-heterocyclic ring. The ultraviolet spectra have been discussed in order to obtain information about the chromophores responsible for the absorption. The infrared spectra have been analyzed for the identification of the main absorption frequencies of cyano and ethylenic groups and to assign the characteristic absorption bands to specific normal vibrations of the heteroaromatic nuclei. 相似文献
9.
Atmospheric bulk deposition of major and trace elements was measured at Venice from November 1995 to October 1997. Collection was carried out using polyethylene bulk passive samplers, samples being collected bi-weekly. In order to highlight the contribution of the atmosphere to water chemistry and particle budgets in the Lagoon of Venice, the geochemical composition (Si, Al, Ca, Mg, K, Na, Mn, Cr, Zn, Pb, Cd, Cu, As) of dissolved and insoluble bulk fractions was determined by AAS + ICP mass spectrometry. Great sample variability was found, with almost two orders of magnitude between maximum and minimum values for several metals. All fluxes in 1995/96 were 30% lower than in 1996/97, ranging from -3% (Ca) to -57% (Li), except for Zn, Cd and As. On the contrary, the solubility of all elements decreased during 1996/97. Partitioning between soluble and insoluble phases shows that Al, Cr, Fe and Si are mainly in the insoluble form, whereas for As, Ca, Cu, Mg, Na, Ni, K, Pb and Zn the dissolved fraction represents 50-90% of total input. The amount of particle load affects partitioning between dissolved and particulate, especially for Al and Pb. Seasonal variability was evident. The lowest pH values (approximately 5.2) were recorded in winter, causing an increase of solubility for all metals except for As, which showed the highest solubility in summer. 相似文献
10.
Bazzicalupi C Bencini A Berni E Bianchi A Ciattini S Giorgi C Maoggi S Paoletti P Valtancoli B 《The Journal of organic chemistry》2002,67(25):9107-9110
The synthesis of three new tris-macrocycles, containing three [12]aneN(4) (L1), [12]aneN(3)O (L2), or [14]aneN(4) (L3) moieties appended to a tren unit, is reported. The crystal structure of the [(Na(ClO(4))(6)) subset L1(2)H(13)]Na(6)Cl(2)(ClO(4))(12) compound shows the anionic cluster [Na(ClO(4))(6)](5)(-) assembled inside the cavity defined by two bowl-shaped polyammonium receptors, held by multiple charge-charge and hydrogen bond interactions. 相似文献