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871.
《Journal of polymer science. Part A, Polymer chemistry》2018,56(15):1684-1694
The fabrication of novel hydrophobic, superhydrophobic, and oleophobic surfaces on glass using nanosilica particles modified with polymer brushes prepared via surface initiated Cu(0)‐mediated reversible‐deactivation radical polymerization was demonstrated. Monomers including n‐butyl acrylate, 2,2,2‐trifluoroethyl methacrylate, and 1,1,1,3,3,3‐hexafluoroisopropyl acrylate were used to synthesize a series of nanosilica–polymer organic/inorganic hybrid materials. Products were analyzed using infrared spectroscopy, thermogravimetric analysis, scanning and transmission electron microscopy. The coated nanosilica showed core–shell structures that contains polymer brushes up to 67 wt %. The application of these particles for modifying surface wettability was examined by covalently attaching them to glass via a recently developed one‐pot “grafting to” methodology using “thio‐bromo click” chemistry. Atomic force microscopy topographic images show up to 25 times increase in roughness of the coated glass compared to blank glass sample. Contact angle measurements showed that nanosilica coated with PBA and PTFEM produced hydrophobic glass surfaces, while a superhydrophobic and oleophobic surface was generated using nanosilica functionalized with PHFIPA. This novel methodology can produce superhydrophobic and oleophobic surfaces in an easy and fast way without the need for tedious and time‐consuming processes, such as layer‐by‐layer deposition, high temperature calcination, and fluorinated oil infusion. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 相似文献
872.
Hiroki Fukumoto Takakazu Yamamoto 《Journal of polymer science. Part A, Polymer chemistry》2008,46(9):2975-2982
A soluble charge‐transfer type poly(aryleneethynylene), PAE‐AzaBzTdz , consisting of a highly electron‐accepting azabenzothiadiazole unit was prepared in 99% yield by palladium‐catalyzed polycondensation between 4,7‐dibromo‐2,1,3‐azabenzothiadiazole ( Br2‐AzaBzTdz ) and 1,4‐diethynyl‐2,5‐didodecyloxybenzene. PAE‐AzaBzTdz showed a number‐average molecular weight, Mn, of 6000 in gel‐permeation chromatography analysis and had good thermal stability as measured by TGA. UV–vis spectrum of PAE‐AzaBzTdz exhibited an absorption peak at 529 nm in chloroform, and the absorption peak shifted to a longer wavelength (601 nm) in film. Addition of MeOH to a CHCl3 solution of PAE‐AzaBzTdz led to aggregation of the polymer to form stable colloidal particles. Results of filtration experiments using 0.2 and 0.02 μm membranes supported aggregation of the polymer. Addition of trifluoroacetic acid (TFA) to a chloroform solution of PAE‐AzaBzTdz led to a red‐shift of the UV–vis peak from 529 to 640 nm. An X‐ray diffraction pattern of powdery PAE‐AzaBzTdz indicated that the polymer assumed a layer‐to‐layer stacked structure with an interlayer distance of 3.4 Å in the solid state. An X‐ray diffraction pattern of cast film of PAE‐AzaBzTdz revealed that the polymer molecules in the cast film were ordered on the surface of Pt plate with the dodecyl side chain oriented toward the surface of the Pt plate. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2975–2982, 2008 相似文献
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874.
E. E. Permyakova 《Russian Mathematics (Iz VUZ)》2008,52(12):41-49
In this paper we prove a theorem on sufficient conditions for the convergence in the Skorokhod space D[0, 1] of a sequence of random processes with random time substitution. We obtain almost sure versions of this theorem. 相似文献
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878.
We study some variations of the so‐called Hardy hierarchy (up to ε0) of quickly growing functions, known from the literature, and obtain analogues of Ratajczyk's approximation lemma for them. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
879.
Yong‐Qin Wei Ke‐Chen Wu Bo‐Tao Zhuang Zhang‐Feng Zhou Ming‐Xin Zhang Cai‐Ping Liu 《无机化学与普通化学杂志》2005,631(8):1532-1535
The silver complex Ag(PPh3)2(H2TMT) ( 1 )(H3TMT = 2,4,6‐trimercapto‐1,3,5‐triazine) has been synthesized and characterized. The ligand trimercaptotriazine exhibits a novel coordination mode and the complex shows a special hydrogen bonding linkage in the crystal packing. The colorless crystals of 1 exhibit broad emission in the visible region at room temperature. TDDFT calculation indicated that the π–π attraction is crucial for fluorescence of the title complex. 相似文献
880.
C.M. da Fonseca 《Discrete Mathematics》2009,309(8):2519-757
Given partitions R and S with the same weight, the Robinson-Schensted-Knuth correspondence establishes a bijection between the class A(R,S) of (0, 1)-matrices with row sum R and column sum S and pairs of Young tableaux of conjugate shapes λ and λ∗, with S?λ?R∗. An algorithm for constructing a matrix in A(R,S) whose insertion tableau has a prescribed shape λ, with S?λ?R∗, is provided. We generalize some recent constructions due to R. Brualdi for the extremal cases λ=S and λ=R∗. 相似文献