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21.
M. A. Morón C. Romero F. R. Ruiz del Portal 《Journal of Optimization Theory and Applications》1996,91(3):643-649
The purpose of this paper is to seek utility functions satisfying a weak condition which guarantees that the utility optimum always belongs to the compromise set. This set is a special subset of the attainable or feasible set, which is generated through the application of the well-known operational research approach called compromise programming. It is shown that there are large families of utility functions satisfying this condition, thus reinforcing the value of compromise programming as a good surrogate of the traditional utility optimum.Thanks are due to the reviewers for their helpful suggestions. The English editing by Ms. Christine Méndez is appreciated. The authors have been supported by the Comisión Interministerial de Ciencia y Tecnología (CICYT), Madrid, Spain. 相似文献
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23.
Tadeusz Balaban Michael O'Carroll Ricardo Schor 《Communications in Mathematical Physics》1989,122(2):233-247
Block renormalization group transformations (RGT) for lattice and continuum Euclidean Fermions in d dimensions are developed using Fermionic integrals with exponential and -function weight functions. For the free field the sequence of actionsD
k
generated by the RGT from D, the Dirac operator, are shown to have exponential decay; uniform ink, after rescaling to the unit lattice. It is shown that the two-point functionD
–1 admits a simple telescopic sum decomposition into fluctuation two-point functions which for the exponential weight RGT have exponential decay. Contrary to RG intuition the sequence of rescaled actions corresponding to the -function RGT do not have uniform exponential decay and we give examples of initial actions in one dimension where this phenomena occurs for the exponenential weight RGT also. 相似文献
24.
Ricardo Fierro James C. W. Chien Marvin D. Rausch 《Journal of polymer science. Part A, Polymer chemistry》1994,32(15):2817-2824
Racemic isopropylidene (1-η5-cyclopentadienyl)(1-η5-indenyl) dichlorozirconium and the 3-methylindenyl derivative have been synthesized and characterized. These precursors activated with methylaluminoxane produce poly(propylene) with hemiisotactic microstructures. © 1994 John Wiley & Sons, Inc. 相似文献
25.
A detailed analysis of one- and two-dimensional 1H and 13C NMR data for the endo and the exo adducts, obtained by Diels-Alder reaction of thuriferic and epithuriferic acids with cyclopentadiene is described. The unequivocal spectral data assignment of the endo and exo structures was complemented with molecular modelling studies and confirmed through X-ray diffraction studies. 相似文献
26.
Ricardo Baggio Juan Carlos Muoz Mireille Perec 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(10):m498-m500
The title compound, [Dy2(C2H3O2)6(H2O)4]·4H2O, crystallizes in the form of dimeric units related by an inversion centre. Each cation is nine‐coordinate, binding to two water molecules and three acetate groups, two of which are bidentate and the third tridentate. This last acetate group acts as a bridge between neighbouring metal atoms, leading to an intradimer Dy?Dy separation of 4.170 (1) Å. 相似文献
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A new graphite-epoxy composite electrode (GECE) containing Bi(NO(3))(3) as a built-in bismuth precursor for simultaneous and individual anodic stripping analysis of heavy trace metals like lead and cadmium is reported. The developed Bi(NO(3))(3)-GECE is compatible with bismuth film electrodes reported previously including the composite electrodes (Bi-GECE) recently reported by our group. Bi(NO(3))(3)-GECE displays the ability for the detection of both individual and simultaneous determination of heavy trace metals and exhibits well defined, reproducible and sharp stripping signals. The sensitive response is combined with the minimal toxicity of Bi(NO(3))(3). This novel sensor would be an appropriate alternative tool to sensors using bismuth in solution during their utilization in environmental quality monitoring as well as other applications. 相似文献
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30.
L.J. del Valle D. Aradilla F. Sepulcre E. Armelin F. Estrany 《European Polymer Journal》2007,43(6):2342-2349
Cell adhesion and proliferation in poly(3,4-ethylenedioxythiophene), an electroactive polythiophene derivative generated by anodic polymerization, has been investigated. Results show that epithelial cells Hep-2 present significant activity on the surface of poly(3,4-ethylenedioxythiophene) electrodeposited on stainless steel electrodes, no sign of cytotoxicity being detected for this conducting polymer. Indeed, seeded and cultured cells bound better to poly(3,4-ethylenedioxythiophene) than to uncoated stainless steel, the latter substrate being used as a control. Furthermore, the electrochemical characteristics of poly(3,4-ethylenedioxythiophene) covered with cells was determined in different biological media using cyclic voltammetry experiments. Results reveal a significant increase in the electroactivity of this material when it is covered with a cellular monolayer. The overall of the results evidences not only the biocompatibility of poly(3,4-ethylenedioxythiophene) with Hep-2 cells but also their electrocompatibility. 相似文献