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61.
Zhaoyang Cheng Shipei Xing Jun Guo Biao Cheng Lan‐Fang Hu Xing‐Hong Zhang Zhan Lu 《中国化学》2019,37(5):421-421
The cover picture shows that sequential 1,1‐dihydrosilylation of terminal aliphatic alkynes with primary silanes enabled by one earth‐abundant cobalt catalyst has been developed. This protocol is operationally simple using readily available aliphatic alkynes, including simple acetylene and complex drug derivative, for efficient access to valuable gem‐bis(dihydrosilyl)alkanes in highly regioselective and atom‐economic manners. Corresponding asymmetric transformations are achieved with excellent enantioselectivities. More details are discussed in the article by Lu et al. on page 457–461.
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We reported the morphology-directed synthesis of Co(3)O(4) nanotubes via interfacial reaction of NaOH with pre-fabricated CoC(2)O(4)·2H(2)O nanorods based on modified Kirkendall effect. The as-obtained Co(3)O(4) nanotubes showed excellent activity and durability in catalytic combustion of CH(4). 相似文献
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苯并噁嗪中间体/蛭石插层纳米复合物热固化行为的研究 总被引:4,自引:0,他引:4
通过对双酚A型苯并嗪中间体 (BOZ A) 蛭石插层纳米复合物固化过程的分析表明长链烷基铵阳离子对BOZ A的热开环聚合反应没有表现出催化作用 ,也不影响纳米复合物的结构形态 .不同蛭石含量的插层纳米复合物 ,在形成不同纳米分散状态的纳米复合物的过程中 ,蛭石晶片对BOZ A的热开环聚合具有明显不同的阻碍作用 ,蛭石含量为 3%的插层纳米复合物 16 0℃的凝胶化时间较纯树脂延长约 7min ,活化能升高约8kJ mol,固化反应热焓降低约 14J g ,使得固化物的固化程度较纯树脂降低约 7%~ 10 % ,阻碍作用最大 ,其它含量的次之 相似文献
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Yadong Yang Zhaoyang Zhong Hongming Liu Tangyou Zhu Jinjin Wu Mengxia Li Dong Wang 《Electroanalysis》2008,20(24):2621-2628
Various sensor‐based immunoassay methods have been extensively developed for the detection of cancer antigen 15‐3 (CA 15‐3), but most often exhibit low detection signals and low detection sensitivity, and are unsuitable for routine use. The aim of this work is to develop a simple and sensitive electrochemical immunoassay for CA 15‐3 in human serum by using nanogold and DNA‐modified immunosensors. Prussian blue (PB), as a good mediator, was initially electrodeposited on a gold electrode surface, then double‐layer nanogold particles and double‐strand DNA (dsDNA) with the sandwich‐type architecture were constructed on the PB‐modified surface in turn, and then anti‐CA 15‐3 antibodies were adsorbed onto the surface of nanogold particles. The double‐layer nanogold particles provided a good microenvironment for the immobilization of biomolecules. The presence of dsDNA enhanced the surface coverage of protein, and improved the sensitivity of the immunosensor. The performance and factors influencing the performance of the immunosensor were evaluated. Under optimal conditions, the proposed immunosensor exhibited a wide linear range from 1.0 to 240 ng/mL with a relatively low detection limit of 0.6 ng/mL (S/N=3) towards CA 15‐3. The stability, reproducibility and precision of the as‐prepared immunosensor were acceptable. 57 serum specimens were assayed by the developed immunosensor and standard enzyme‐linked immunosorbent assay (ELISA), respectively, and the results obtained were almost consistent. More importantly, the proposed methodology could be further developed for the immobilization of other proteins and biocompounds. 相似文献
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Majid Montazer Esfandiar PakdelAuthor vitae 《Journal of Photochemistry and Photobiology, C: Photochemistry Reviews》2011,12(4):293-303
The consumption of titanium dioxide in today's world is on the increase. As the most popular nano substance, TiO2 is used in various industries notably in the textile industry. More and more recently, through a synergistic combination of photocatalytic features of nanoparticles, fabrics with novel properties are produced. Self-cleaning and stability against UV rays as well as chemical media, to name but a few, are among new prominent properties, obtained on textiles. A common subject reported in most studies has been the diverse approaches to immobilize the nanoparticles on the surface of fabrics. Wool is among common textile materials that have undergone numerous processes to be modified. This review intends to bring to light different aspects of application of nano titanium dioxide in the textile industry especially on wool, and also presents a concise overview on the rigorous pieces of research conducted in this realm. 相似文献
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Stacy Slavin James Burns David M. Haddleton C. Remzi Becer Author vitae 《European Polymer Journal》2011,47(4):435-446
This mini-review describes recent work in the field of glycopolymer synthesis, with a focus on methods that have employed “click chemistry” and controlled polymerization methodology. A variety of carbohydrates with clickable groups such as azide, alkyne, and thiol moieties provide new routes to glycopolymers. Several studies use copper catalyzed azide-alkyne cycloaddition (CuAAC) reactions to synthesize glycomonomers or to incorporate carbohydrates into a clickable polymeric backbone. Alternatively, there are many thiol based click reactions which provide metal-free synthesis, which are discussed in details. 相似文献