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Aleksei Yu. Grishko Elena A. Zharenova Eugene A. Goodilin Alexey B. Tarasov 《Mendeleev Communications》2021,31(2):163-165
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134.
Polymerizable Molecular Silsesquioxane Cage Armored Hybrid Microcapsules with In Situ Shell Functionalization
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Dr. Yuxiu Xing Dr. Jun Peng Prof. Kai Xu Dr. Weihong Lin Dr. Shuxi Gao Yuanyuan Ren Xuefeng Gui Shengyuan Liang Prof. Mingcai Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(6):2114-2126
We prepared core–shell polymer–silsesquioxane hybrid microcapsules from cage‐like methacryloxypropyl silsesquioxanes (CMSQs) and styrene (St). The presence of CMSQ can moderately reduce the interfacial tension between St and water and help to emulsify the monomer prior to polymerization. Dynamic light scattering (DLS) and TEM analysis demonstrated that uniform core–shell latex particles were achieved. The polymer latex particles were subsequently transformed into well‐defined hollow nanospheres by removing the polystyrene (PS) core with 1:1 ethanol/cyclohexane. High‐resolution TEM and nitrogen adsorption–desorption analysis showed that the final nanospheres possessed hollow cavities and had porous shells; the pore size was approximately 2–3 nm. The nanospheres exhibited large surface areas (up to 486 m2 g?1) and preferential adsorption, and they demonstrated the highest reported methylene blue adsorption capacity (95.1 mg g?1). Moreover, the uniform distribution of the methacryloyl moiety on the hollow nanospheres endowed them with more potential properties. These results could provide a new benchmark for preparing hollow microspheres by a facile one‐step template‐free method for various applications. 相似文献
135.
《Journal of Coordination Chemistry》2012,65(18):3188-3204
Four organic–inorganic crystals, [(HL1)2(ZnCl4)]·H2O (1) (L1?=?2-methylquinoline), [(HL1)2(CuCl4)] (2), [(HL2)2SnCl6] (3) (L2?=?6-bromobenzo[d]thiazol-2-amine), and [(HL3)FeCl4] (4) (L3?=?5,7-dimethyl-1,8-naphthyridine-2-amine), derived from N-containing aromatic Brønsted bases and metal(II) chlorides (zinc(II) chloride, copper(II) chloride dihydrate, tin(II) chloride dihydrate, and iron(III) chloride hexahydrate) were prepared at room temperature and characterized by IR, X-ray structure analysis, elemental analysis, and TG analysis. The crystals are built up by perchlorometallates (Zn, Cu, Sn, and Fe) associated with organic cations through multiple non-covalent associations. X-ray diffraction analysis reveals that 1 and 2 have 3-D network structures built from hydrogen bonds between the cations and chlorometallates. Water molecules play an important role in structure extension in 1. Anhydrous 3 and 4 produced from 2-aminoheterocyclic derivatives display 2-D sheet structures. Arrangements of anions and cations are dominated by shape and size of cations, and also by the different structures of the chlorometallates as well as non-bonding interactions in the crystal structures. Except for 1, the other compounds are thermally stable below 240°C. 相似文献
136.
A new class of stereoregular vinylene‐arylene copolymers with double‐decker silsesquioxane in the main chain
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Michał Dutkiewicz Monika Ludwiczak Bogdan Marciniec Marek Nowicki 《Journal of polymer science. Part A, Polymer chemistry》2016,54(8):1044-1055
A synthesis of a new macromolecular class of vinylene‐arylene copolymers with double‐decker silsesquioxane in the main chain is presented. Two transition‐metal‐catalyzed processes, which is silylative‐coupling copolycondensation (SCC) and ADMET copolymerization of divinyl‐substituted double‐decker silsesquioxanes (DDSQ‐2SiVi) with selected diolefins, are reported to be highly efficient tools for the formation of stereoregular copolymers containing DDSQ‐silylene‐vinylene‐arylene units. The copolymeric products are studied in terms of their structural, thermal, and mechanical properties. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1044–1055 相似文献
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138.
A high‐order element based adaptive mesh refinement strategy for three‐dimensional unstructured grid
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Adaptive mesh refinement (AMR) shows attractive properties in automatically refining the flow region of interest, and with AMR, better prediction can be obtained with much less labor work and cost compared to manually remeshing or the global mesh refinement. Cartesian AMR is well established; however, AMR on hybrid unstructured mesh, which is heavily used in the high‐Reynolds number flow simulation, is less matured and existing methods may result in degraded mesh quality, which mostly happens in the boundary layer or near the sharp geometric features. User intervention or additional constraints, such as freezing all boundary layer elements or refining the whole boundary layer, are required to assist the refinement process. In this work, a novel AMR strategy is developed to handle existing difficulties. In the new method, high‐order unstructured elements are first generated based on the baseline mesh; then the refinement is conducted in the parametric space; at last, the mesh suitable for the solver is output. Generating refined elements in the parametric space with high‐order elements is the key of this method and this helps to guarantee both the accuracy and robustness. With the current method, 3‐dimensional hybrid unstructured mesh of huge size and complex geometry can be automatically refined, without user intervention nor additional constraints. With test cases including the 2‐dimensional airfoil and 3‐dimensional full aircraft, the current AMR method proves to be accurate, simple, and robust. 相似文献
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O. Amri S. Abid M. Rzaigui 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):766-777
The crystal structure of a new organic cation cyclohexaphosphate, [4-ClC 6 H 4 CH 2 NH 3 ] 4 Li 2 P 6 O 18 .4H 2 O, is reported. It crystallizes in the triclinic system (space group P-1) with the following unit-cell parameters: a = 9.628(8), b = 12.801(9), c = 19.528(6) Å, α = 78.60(4)°, β = 83.00(5)°, β = 89.98(4)°, Z = 2, and V = 2341(3)Å 3 . The structure has been solved using direct methods and refined by least-squares analysis [R 1 = 0.043, wR 2 = 0.108]. The structure can be described as infinite anionic layers with composition of [Li 2 (P 6 O 18 )(H 2 O) 4 ] 4 ? and parallel to the ac plane. The organic groups are located in the accessible voids. The molecules are stabilized by O─H…O and N─H…O types of intermolecular hydrogen bonds in the unit cell in addition to Van der Waals forces. 相似文献