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991.
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A benzophenone‐naphthalimide derivative as versatile photoinitiator of polymerization under near UV and visible lights 下载免费PDF全文
Jing Zhang Nicolas Zivic Frédéric Dumur Pu Xiao Bernadette Graff Didier Gigmes Jean Pierre Fouassier Jacques Lalevée 《Journal of polymer science. Part A, Polymer chemistry》2015,53(3):445-451
A benzophenone‐naphthalimide derivative (BPND) bearing tertiary amine groups has been developed as a high‐performance photoinitiator in combination with 2,4,6‐tris(trichloromethyl)‐1,3,5‐triazine or an iodonium salt for both the free radical polymerization (FRP) of acrylates and the cationic polymerization (CP) of epoxides upon exposure to near UV and visible LEDs (385–470 nm). BPND can even produce radicals without any added hydrogen donor. The photochemical mechanisms are studied by molecular orbital calculations, steady state photolysis, electron spin resonance spin trapping, fluorescence, cyclic voltammetry and laser flash photolysis techniques. These novel BPND based photoinitiating systems exhibit an efficiency higher than that of the well‐known camphorquinone‐based systems (FRP and CP) or comparable to that of bis(2,4,6‐trimethylbenzoyl)‐phenylphosphineoxide (FRP at λ ≤ 455 nm). © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 445–451 相似文献
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We provide an effective characterization of the planar octagonal tilings which admit weak local rules. As a corollary, we show that they are all based on quadratic irrationalities, as conjectured by Thang Le in the 1990s. 相似文献
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Dorian Sonet Mattéo Cayla Dr. Raphaël Méreau Estelle Morvan Aline Lacoudre Dr. Nicolas Vanthuyne Muriel Albalat Dr. Dario M. Bassani Dr. Antoine Scalabre Dr. Emilie Pouget Prof. Dr. Brigitte Bibal 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(72):e202202695
Chiral trifluoromethyl alcohol groups were introduced at the hindered ortho positions of 9,10-diphenylanthracenes to investigate their effects on the physical properties and reactivity towards oxidative dearomatization. In such compact structures, the position in different quadrants and the preferred orientation of the −CH(OH)CF3 groups were determined by the relative and absolute configurations of each stereoisomer, respectively. As a consequence, the stereochemistry governs the organization of the H-bonded molecules in single crystals (homochiral dimers vs ribbon), whereas in chlorinated solvents, they all behave as discrete compounds. Concerning their reactivity, the stereospecific dearomative oxidation of these molecules leads to 9,10-bis-spiro-isobenzofuran-anthracenes, when using organic single-electron transfer oxidants. The chiroptical properties of the alcohols and the corresponding dearomatized products were compared and showed an important modulation of the intensity. 相似文献
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In this work, crack initiation in adhesive lap joints of arbitrary joint configuration is studied by means of a finite fracture mechanics approach. The analysis is based on a general stress solution for adhesive joints combined with a coupled stress and energy criterion. The instantaneous formation of a crack of finite size is predicted if a stress and energy criterion are satisfied simultaneously. The closed-form analytical solution of the stress field allows for an efficient evaluation of the crack initiation load and corresponding finite crack length. A comparison to experimental results from literature and to numerical results obtained with a cohesive zone model approach shows a good agreement. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献