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Novel fluoroalkyl end‐capped vinyltrimethoxysilane oligomer/hydroxyapatite (HAp) nanocomposites were prepared by the reaction of calcium nitrate tetrahydrate and phosphoric acid in the presence of the corresponding oligomer. These fluorinated oligomer/HAp composites thus obtained are nanometer size‐controlled fine particles (83–173 nm), and were found to exhibit good dispersibility in methanol, ethanol, and isopropyl alcohol. These fluorinated HAp nanocomposites were applied to the surface modification of glass and poly(methyl methacrylate) (PMMA) to exhibit good hydro‐ and oleophobic characteristics imparted by fluorine on their surface. In addition, the surface structural changes of the modified polyethylene terephtalate and PMMA films treated with these fluorinated nanocomposites before and after soaking in a simulated body fluid (SBF) were analyzed by using SEM, XRD, and EDX to observe the formation of spherical HAp deposits on the surface. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Diogo P. Rivelli Carlos A. H. Filho Rebeca L. Almeida Cristina D. Ropke Tânia C. H. Sawada Silvia B. M. Barros 《Photochemistry and photobiology》2010,86(5):1005-1007
Chlorogenic acid is a natural potent antioxidant. It can be used in cosmetics formulations, but for this purpose its photochemical stability should be determined to ensure that the compound will not be degraded after UV radiation exposure. To evaluate this possibility, the concentration of a chlorogenic acid solution was determined by HPLC before and after UVA and UVB irradiation. The results indicate that chlorogenic acid is not degraded under UVA or UVB irradiation. 相似文献
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Jinno K Sawada H Catabay AP Watanabe H Sabli NB Pesek JJ Matyska MT 《Journal of chromatography. A》2000,887(1-2):479-487
Packed column capillary electrochromatography (CEC), open-tubular CEC and microcolum liquid chromatography (LC) using a cholesteryl silica bonded phase have been studied to compare the retention behavior for benzodiazepines. It has been found that packed column CEC gives better resolution, faster analysis time than microcolumn LC for benzodiazepines maintaining similar selectivity except for some solutes which are charged species under the separation conditions. However, open-tubular CEC gave different selectivities to a larger extent for charged benzodiazepines from that which should be produced by the chromatographic properties of the cholesteryl silica phase. Charged species migration times are mainly influenced by electrophoretic mobility rather than the chromatographic interactions. 相似文献
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Keiju Sawada Toshihiro Yamase 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(11):i149-i151
In the crystal structure of the title compound, Na9[Dy(W5O18)2]·35H2O, the complex anion has approximate D4d symmetry, with Dy—O and W—O distances in the ranges 2.355 (6)–2.405 (6) and 1.715 (7)–2.369 (5) Å, respectively. 相似文献
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Discriminantal arrangement, 3 × 3 minors of Plücker matrix and hypersurfaces in Grassmannian Gr(3,n)
We show that points in specific degree-2 hypersurfaces in the Grassmannian correspond to generic arrangements of n hyperplanes in with associated discriminantal arrangement having intersections of multiplicity three in codimension two. 相似文献