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51.
Combined DFT calculations and UV-vis-NIR, ESR, and SQUID measurements revealed that the ground-state electronic structure of a linear π-conjugated oligomer dication composed of two pyrrole and six or seven thiophene rings and methylthio end-capping units is dominated by a singlet biradical character. 相似文献
52.
Guest‐binding affinities of water‐soluble cyclophane heptadecamer (1) and pentamer (2) with immobilized guests such as 1‐pyrenylmethylamine (PMA) and 2‐(1‐ naphthyl)ethylamine (NEA) were investigated by surface plasmon resonance (SPR) measurements. As a typical example, the binding constants (K) for 1 and 2 with the immobilized PMA as a guest were evaluated to be 2.5 × 107 and 2.7 × 106 M?1, respectively, and were much larger than that of a monocyclic reference cyclophane (K, 2.5 × 104 M?1). Interestingly, in the complexation of 1 and 2 with the immobilized guests, more favorable association and dissociation rate constant values (ka and kd, respectively) were observed in comparison with those for the monocyclic cyclophane, reflecting multivalent effects in macrocycles. The multivalent effects in macrocycles as well as molecular recognition abilities of the cyclophane oligomers were confirmed even when the guest molecules were immobilized on SPR sensor chip surfaces. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
53.
In this study, we present a new method for placing markers for alignment of tomographic tilt-series of rod-shaped specimen before 3D reconstructions. By this method, markers (gold nanoparticles) were placed only on the carbon layer (referred to as the "marker area") deposited for protecting the specimen surface against ion beam irradiation; this placement was achieved by vacuum evaporation of gold with the help of a mask fabricated adjacent to the specimen. Experimental results showed that the use of the proposed method facilitates the identification of the markers in the alignment process, because the image of the marker area consists of simple high-contrast images of the gold nanoparticles on the carbon layer. The performance of the proposed method was successfully verified experimentally by applying it to a high-density Au/SiO? nanocomposite material as a test specimen. 相似文献
54.
Ichiro Nishizaki Hideki Katagiri Tomohiro Hayashida 《Central European Journal of Operations Research》2010,18(3):383-396
A multiattribute utility function can be represented by a function of single-attribute utility functions if the decision maker’s
preference satisfies additive independence or mutually utility independence. Additive independence is a preference condition
stronger than mutually utility independence, and the multiattribute utility function is in the additive form if the former
condition is satisfied, otherwise it is in the multiplicative form. In this paper, we propose a method for sensitivity analysis
of multiattribute utility functions in multiplicative form, taking into account the imprecision of the decision maker’s judgment
in the procedures for determining scaling constants (attribute weights). 相似文献
55.
56.
We report on an interdisciplinary approach to the study of finds of unfired clay lumps and unfired broken vessels from two workshops in the Leche Valley, north coast of Peru. The material is used as a reference in the study of pottery making at both workshops. 相似文献
57.
Noriko Hata Shiho Hieda Mika Yamada Rie Yasui Hideki Kuramitz Shigeru Taguchi 《Analytical sciences》2008,24(7):925-928
The formation of a liquid organic ion associate in an aqueous sample was applied to the concentration and determination of cadmium in environmental water samples. Cadmium was converted into a complex with 2-(5-bromo-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino)phenol (5-Br-PAPS) in a 40-mL sample solution, and was extracted into a liquid ion associate of phenolsulfonate and benzethonium during phase formation. More than 400-fold enrichment was easily attained by this technique, because the volume of the liquid organic phase formed was very small, ca. 2 microL. After dilution of the organic phase with a small volume of 2-methoxyethanol, the cadmium in the solution was determined by GF-AAS. The detection limit was 0.09 ng/L (3sigma(b)). This method was applied to the determination of cadmium in river water and seawater. 相似文献
58.
Mika Seppälä 《Discrete and Computational Geometry》1994,11(1):65-81
In this paper we derive a numerical method which allows us to compute periods of differentials on areal algebraic curve with real points. This leads to an algorithm which can be implemented on a computer and can be used to study the Torelli mapping numerically.
Dedicated to the memory of Mario Raimondo
This work was supported by the EC Science Plan Contract No. SC1*-CT91-0716 and the Academy of Finland. 相似文献
59.
Sur les immeubles triangulaires et leurs automorphismes 总被引:1,自引:0,他引:1
Résumé Les travaux de J. Tits ont conduit à la classification complète des immeubles euclidiens de dimension supérieure ou égale
à 3. L’ensemble de ces immeubles à isomorphisme près est dénombrable et paramétré par les corps locaux qui leur correspondent.
Dans cet article nous nous intéressons aux immeubles triangulaires, qui sont euclidiens de dimension 2 et pour lesquelles
une paramétrisation analogue est impossible. Nous construisons une lamination Λ sur un espace topologique localement compact
séparé, dont l’espace des feuilles est l’ensemble des immeubles triangulaires à isomorphisme près. On considère ainsi les
immeubles triangulaires comme points d’un espace dont Λ est une désingularisation naturelle. Nous établissons des résultats
de chirurgie sur les immeubles triangulaires à données locales fixées. Ils entra?nent par exemple que Λ est topologiquement
transitive. Nous montrons qu’un immeuble triangulaire générique au sens de Baire a un groupe d’automorphismes trivial et qu’il
contient toutes les géométries locales possibles. L’espace des immeubles triangulaires à isomorphisme près est un nouvel exemple
d’espace non commutatif.
Le second auteur a été en partie financé par JSPS. 相似文献
60.
Noora Ristolainen Ulla Vainio Santeri Paavola Mika Torkkeli Ritva Serimaa Jukka Seppl 《Journal of Polymer Science.Polymer Physics》2005,43(14):1892-1903
The properties of polypropylene composites can be tailored through the use of nanoclay fillers. The effectiveness of a metallocene‐catalyzed hydroxyl‐functional polypropylene in the compatibilization of polypropylene layered nanosilicate composites was studied, and the results were compared with those for a commercial maleic anhydride functionalized polypropylene. Polypropylene/organoclay nanocomposites were prepared by melt blending, and two polypropylene/compatibilizer/organoclay ratios, 90/5/5 and 70/20/10, were characterized. The organomodification of the clay was carried out with octadecylamine and N‐methylundecenylamine. The structure of the layered silicate was studied by transmission electron microscopy, wide‐angle X‐ray scattering, and small‐angle X‐ray scattering. The fracture surfaces of the composites and thus the efficiency of the compatibilizers to penetrate the galleries of the organoclays were characterized by scanning electron microscopy, and the melt viscosity was studied by stress‐controlled rotational rheometry. The nanostructure was observed with both alkyl amines used for intercalation. The fillers facilitated the processability of all the composites, consisting of equal amounts of compatibilizer and organoclay filler and, in some of the composites, containing twice as much compatibilizer as organoclay filler. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1892–1903, 2005 相似文献