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71.
72.
Hussein Awada Hussein Medlej Sylvie Blanc Marie‐Hélène Delville Roger C. Hiorns Antoine Bousquet Christine Dagron‐Lartigau Laurent Billon 《Journal of polymer science. Part A, Polymer chemistry》2014,52(1):30-38
We demonstrate an efficient strategy to anchor poly(3‐hexylthiophene) (P3HT) onto zinc oxide (ZnO) surfaces. Synthesis of a novel triethoxysilane‐terminated regioregular P3HT is herein reported and supported by thorough characterization. Three triethoxysilane‐terminated P3HTs of different molar masses were prepared via a hydrosilylation reaction from allyl‐terminated P3HT. MALDI‐TOF and 1H NMR were performed to characterize the polymer and show that around 80% of the chains are end‐functionalized. These polymers were then grafted onto the ZnO nanorods to create a macromolecular self‐assembled monolayer. This versatile technique could be subsequently applied to different metal oxide surfaces, such as silicon, titanium, or indium‐tin oxide, and represents a new one‐pot strategy based on triethoxysilane coupling reaction. Importantly, the influence of the molar mass on the grafting density and the polymer shell thickness was studied via thermo gravimetric analysis and transmission electron microscopy. The optical properties of the hybrid materials were determined by UV–visible absorption and photoluminescence to show a quenching effect of P3HT fluorescence by ZnO when grafted. This electronic transfer associated with an improved miscibility of the ZnO@P3HT, makes these hybrid materials suitable candidates for photovoltaic applications. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 30–38 相似文献
73.
In this article, we propose new Monte Carlo techniques for moving a diffusive particle in a discontinuous media. In this framework, we characterize the stochastic process that governs the positions of the particle. The key tool is the reduction of the process to a Skew Brownian motion (SBM). In a zone where the coefficients are locally constant on each side of the discontinuity, the new position of the particle after a constant time step is sampled from the exact distribution of the SBM process at the considered time. To do so, we propose two different but equivalent algorithms: a two-steps simulation with a stop at the discontinuity and a one-step direct simulation of the SBM dynamic. Some benchmark tests illustrate their effectiveness. 相似文献
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Maud Jenart Claude Niebel Jean-Yves Balandier Julie Leroy Alix Mignolet Sara Stas Antoine Van Vooren Jérôme Cornil Yves Henri Geerts 《Tetrahedron》2012,68(1):349-355
Two quaterthiophene-based dimers including an ethylene bridge have been designed and efficiently prepared; experimental and computational studies show a promising potential as semiconducting material with a charge transport of higher dimensionality compared to quaterthiophene. 相似文献
76.
Importance of the Correlation between Width and Length in the Shape Analysis of Nanorods: Use of a 2D Size Plot To Probe Such a Correlation
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Prof. Clément Roux Dr. Céline Delmas Prof. Jean‐Daniel Marty Dr. Myrtil L. Kahn Dr. Christophe Mingotaud 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(35):12424-12429
Analysis of nanoparticle size through a simple 2D plot is proposed in order to extract the correlation between length and width in a collection or a mixture of anisotropic particles. Compared to the usual statistics on the length associated with a second and independent statistical analysis of the width, this simple plot easily points out the various types of nanoparticles and their (an)isotropy. For each class of nano‐objects, the relationship between width and length (i.e., the strong or weak correlations between these two parameters) may suggest information concerning the nucleation/growth processes. It allows one to follow the effect on the shape and size distribution of physical or chemical processes such as simple ripening. Various electron microscopy pictures from the literature or from the authors′ own syntheses are used as examples to demonstrate the efficiency and simplicity of the proposed 2D plot combined with a multivariate analysis. 相似文献
77.
Natalia Castro Christine Raynaud Antoine Rouilly Luc Rigal Christian Quellet 《高分子科学杂志,C辑:聚合物评论》2016,56(1):137-186
Encapsulation of flavor and aroma compounds has been largely explored in order to meet appraisal demands from consumers by improving the impact of flavor during the consumption of food products. Even though several techniques have been used for encapsulating volatile compounds, i.e., spray drying, fluidized bed coating, coacervation, and melt extrusion, those most frequently used in the food industry are spray drying and melt extrusion. In this article, the different techniques of encapsulation of flavors and fragrances in polymer-based matrices by extrusion are reviewed and partly re-defined, emphasizing the differences between the various techniques reported so far and the role of matrix types, additives, and operative conditions. Also, the role of water as a key parameter for controlled release and shelf stability of the delivery system will be discussed. 相似文献
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79.
Anne-Marie Caminade Fayez El Khatib Antoine Baceiredo Max Koenig 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2-4):365-367
Abstract The ozonization of various halophosphines 1a-j leads with quantitative yields to the corresponding phosphine oxides 2a-j. Ozonization is a convenient method of oxidation, in particular of compounds with bulky ligands (1c, 1d, 1e). 相似文献
80.
Sakey Ravindra Kokkarachedu Varaprasad V. Rajinikanth Antoine F. Mulaba-Bafubiandi Koduri Venkata Surya Ramam 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1230-1240
Design of silver nanoparticles containing poly(N-isopropylarclamide) (PNIPAAm) hydrogels were prepared by free-radical polymerization of N-isopropylarclamide as an environmentally sensitive monomer and MBA as a crosslinker in an aqueous medium. The embedded silver nanocomposite hydrogels (AgNCH) structure were characterized by, UV-Vis, FTIR, DLS, TEM and X-ray analysis. Curcumin loading and release characteristics were performed for PNIPAAm hydrogel, silver ions loaded hydrogels as well as silver nanocomposite hydrogels. These curcumin loaded silver nanocomposite hydrogels exhibit excellent antibacterial action on Escherichia coli (E. coli). Therefore, the present study clearly provides novel antimicrobial hydrogels which are potentially useful in biomedical applications. 相似文献