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Ionics - C/CuO nanocomposites were prepared by hydrothermal treatment of copper nitrate with starch, followed by H2O2 oxidation and calcination. Structure characterizations show that high... 相似文献
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Back Cover: Ultrasound‐Driven Secondary Self‐Assembly of Amphiphilic β‐Cyclodextrin Dimers (Chem. Eur. J. 13/2015) 下载免费PDF全文
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Novel hyperbranched polymers synthesized via A3 + B(B′) approach by radical addition‐coupling polymerization 下载免费PDF全文
In this study, a novel application of radical addition‐coupling polymerization (RACP) for synthesis of hyperbranched polymers is reported. By Cu/PMDETA‐mediated RACP of 2‐methyl‐2‐nitrosopropane with trimethylolpropane tris(2‐bromopropionate) or a bromo‐ended 3‐arm PS macromonomer, two types of hyperbranched polymers with high degree of polymerization are synthesized under mild conditions, respectively. The chemical structures of the hyperbranched polymers are carefully characterized. By selective degradations of the ester groups and weak bonds of NO? C in the polymers, high degree of alternative connection of the two monomers in the synthesized polymers have been identified. Based on the experimental results, mechanism of formation of the hyperbranched polymer is proposed, which includes formation of carbon radicals from the tribromo monomer through single electron transfer, its capture by 2‐methyl‐2‐nitrosopropane that results in nitroxide radical, and cross‐coupling reaction of the nitroxide radical with other carbon radicals. Hyperbranched polymer can be formed in a step‐growth mode after multiple steps of such reactions. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 904–913 相似文献
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CdS sensitized NiO electrode was used as the photoactive cathode in a photoelectrochemical cell for water splitting,avoiding the use of a sacrificial electron donor.Photocurrent increment under visible light irradiation was observed after integration of[Co(dmgH)2(4-Me-py)Cl](1) to the photocathode,suggesting 1 could accept electrons from photoexcited CdS for water reduction and NiO could move the holes in the valence band of CdS to anode for water oxidation. 相似文献
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In the present research, hierarchical structure observation and mechanical property characterization for a type of biomaterial are carried out. The investigated biomaterial is Hyriopsis cumingii, a typical limnetic shell, which consists of two different structural layers, a prismatic "pillar"structure and a nacreous "brick and mortar" structure. The prismatic layer looks like a "pillar forest" with variationsection pillars sized on the order of several tens of microns.The nacreous material looks like a "brick wall" with bricks sized on the order of several microns. Both pillars and bricks are composed of nanoparticles. The mechanical properties of the hierarchical biomaterial are measured by using the nanoindentation test. Hardness and modulus are measured for both the nacre layer and the prismatic layer, respectively.The nanoindentation size effects for the hierarchical structural materials are investigated experimentally. The results show that the prismatic nanostructured material has a higher stiffness and hardness than the nacre nanostructured material.In addition, the nanoindentation size effects for the hierarchical structural materials are described theoretically, by using the trans-scale mechanics theory considering both strain gradient effect and the surface/interface effect. The modeling results are consistent with experimental ones. 相似文献
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A Convenient Synthesis of N‐Aryl Benzamides by Rhodium‐Catalyzed ortho‐Amidation and Decarboxylation of Benzoic Acids 下载免费PDF全文
Dr. Xian‐Ying Shi Ke‐Yan Liu Juan Fan Xue‐Fen Dong Prof. Dr. Jun‐Fa Wei Prof. Dr. Chao‐Jun Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(5):1900-1903
The rhodium‐catalyzed amidation of substituted benzoic acids with isocyanates by directed C?H functionalization followed by decarboxylation to afford the corresponding N‐aryl benzamides is demonstrated, in which the carboxylate serves as a unique, removable directing group. Notably, less common meta‐substituted N‐aryl benzamides are generated readily from more accessible para‐ or ortho‐substituted groups by employing this strategy. 相似文献