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991.
We examine new second-order necessary conditions and sufficient conditions which characterize nondominated solutions of a generalized constrained multiobjective programming problem. The vector-valued criterion function as well as constraint functions are supposed to be from the class C
1,1. Second-order optimality conditions for local Pareto solutions are derived as a special case. 相似文献
992.
Michal Kedem Shlomo Margel 《Journal of polymer science. Part A, Polymer chemistry》2002,40(9):1342-1352
Polystyrene template microspheres of 1.4 ± 0.1 μm were prepared by dispersion polymerization of styrene in a mixture of ethanol and 2‐methoxy ethanol. These template particles were then swelled at room temperature in a single step with emulsion that was prepared in sodium dodecyl sulfate aqueous solution from a swelling solvent (dibutyl phthalate) containing the initiator (benzoyl peroxide) and monomer(s) (chlormethylstyrene, divinylbenzene, or ethylene dimethacrylate). Composite uniform particles composed of the template polystyrene and noncrosslinked or crosslinked polychloromethylstyrene were prepared by polymerizing the monomer(s) within the swelled particles at 73 °C. Crosslinked uniform polychloromethylstyrene particles of higher surface area were formed by dissolving the template polystyrene polymer of the composite particles. The influence of various reaction parameters, such as dibuthyl phthalate concentration, chloromethylstyrene concentration, crosslinker type and concentration, and so forth on the molecular weight, size, size distribution, shape, morphology, surface area, and decomposition temperature of the particles was investigated. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1342–1352, 2002 相似文献
993.
Functionalized alkylidene-cyclobutanes have been prepared from 2-fluoropyridinyl-6-oxy precursors derived from vinyl cyclobutanols by a radical addition-elimination process. A wide range of functional groups is tolerated, and the alkylidene-cyclobutanes can be further elaborated into cyclopentanones. The limitation of this approach resides in the competition with opening of the cyclobutane ring. 相似文献
994.
995.
996.
997.
We give a full topological characterization of omega limit sets of continuous maps on graphs and we show that basic sets have similar properties as in the case of the compact interval. We also prove that the presence of distributional chaos, the existence of basic sets, and positive topological entropy (among other properties) are mutually equivalent for continuous graph maps. 相似文献
998.
Michal Krizek 《Discrete and Computational Geometry》2006,36(2):381-390
We prove that a point in the Euclidean space R5 cannot be surrounded by a finite number of acute simplices. This fact implies that there does not exist a face-to-face partition
of R5 into acute simplices. The existence of an acute simplicial partition of Rd for d > 5 is excluded by induction, but for d = 4 this is an open problem.
Dedicated to Prof. Miroslav Fiedler on the occasion of his 80th birthday 相似文献
999.
Jan Fbry Michal Duek Karla Fejfarov Radmila Krupkov Pemysl Vank Ivana Císaov 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(6):i49-i52
The structure of Rb2PO3F was determined at 290 and 130 K, while that of Cs2PO3F was determined at 240 and 100 K. Both compounds belong to the β‐K2SO4 family. The structure analysis did not reveal signs of a phase transition in either compound. Crystal chemical considerations do not favour the presence of a phase transition in either Rb2PO3F or Cs2PO3F. However, glass‐like phase transitions were observed by differential scanning calorimetry in slightly humid samples at 175 and 177 K for Rb2PO3F and Cs2PO3F, respectively, but were not observed in well dried samples. The bond distances are normal and Cs2PO3F is twinned. 相似文献
1000.
Michal Marvan Alexandre M. Vinogradov Valery A. Yumaguzhin 《Central European Journal of Mathematics》2007,5(1):105-133
In this paper basic differential invariants of generic hyperbolic Monge-Ampère equations with respect to contact transformations
are constructed and the equivalence problem for these equations is solved.
相似文献