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131.
Journal of Nanoparticle Research - The demand for metal nanoparticles is increasing strongly. Transferred arc synthesis is a promising process in this respect, as it shows high production rates,... 相似文献
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A facile route to improve photoluminescent performance and service lifetime of a promising blue light emitting material is reported and demonstrated here using a copolymer system of N-(2-ethylhexyl)-2,7-carbazole (Cz) and 1,3,5,7-tetrakis- (4-bromophenyl) adamantane (TBA). The copolymers were successfully synthesized by palladium-catalyzed Suzuki coupling reactions. Structure and molecular weight of the materials were characterized by FT-IR and 1H-NMR spectroscopies, elemental analysis and gel permeation chromatography. The influence of adamantane content on the thermal stability and photoluminescent performance of the synthesized copolymers was investigated in detail. DSC results showed that glass transition temperature increased dramatically, from 68°C for neat carbazole, to 88°C, 120°C and 152°C, after the addition of 10%, 20%, and 30% TBA, respectively. The same trend was found when thermal decomposition temperature at 5% weight loss was evaluated from TGA data. Importantly, this increased stability can be extended to thermo-optical performance, with the Cz-TBA system showing higher color purity and stronger emission intensity within blue light wavelength than carbazole alone. Nevertheless, measurements of emitting spectral stability at a broader temperature range (100–200°C) and photoluminescence quantum yield suggested that there is a delicate trade-off between the performance and adamantane content. 相似文献
134.
Chen Chen Weng Xinliang Xu Xiao Xia Xiong Xiu Lian Lu Yi Feng Zhou 《Russian Journal of General Chemistry》2013,83(12):2447-2452
We have demonstrated that the fragments of Telaprevir can act as organocatalysts for asymmetric aldol reactions between aromatic aldehydes and acetone under mild conditions. The reaction conditions have been optimized in terms of the catalyst nature, choice of temperature, solvent, additive, and the catalyst loading. Under proper conditions, fairly good yield and enantioselectivity have been achieved. 相似文献
135.
Chen Haijun Wang Youqun Zhao Wuwei Xiong Guoxuan Cao Xiaohong Dai Ying Le Zhanggao Zhang Zhibin Liu Yunhai 《Journal of Radioanalytical and Nuclear Chemistry》2017,313(1):175-189
Journal of Radioanalytical and Nuclear Chemistry - The graphene oxide (GO) was functionalized with phosphate groups and applied as an effective adsorbent for the removal of uranium from aqueous... 相似文献
136.
发展了一种经济、简单的海蛎壳粉负载的CuCl2异相催化剂OSP-CuCl2,用来催化醛-炔-胺之间的A3偶联反应.OSP-CuCl2容易通过简单的方法从海蛎壳粉以及CuCl2制备,且显示出高的催化活性以及良好的可循环回收性.在微波辅助以及无溶剂条件下,以OSP-CuCl2为催化剂,能够以高产物收率制备出一系列炔胺类化合物.OSP-CuCl2可通过简单的过滤方式进行回收,并至少可循环使用6次.初步放大实验表明,炔胺类化合物能够以150 mmol的规模制备(87%收率). 相似文献
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138.
A Pronounced Halogen Effect on the Organogelation Properties of Peripherally Halogen Functionalized Poly(benzyl ether) Dendrons 下载免费PDF全文
Prof. Dr. Yu Feng Hui Chen Zhi‐Xiong Liu Yan‐Mei He Prof. Dr. Qing‐Hua Fan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(14):4980-4990
An interesting halogen‐substituent effect on the organogelation properties of poly(benzyl ether) dendrons is reported. A new class of poly(benzyl ether) dendrons with halo substituents decorating their periphery was synthesized and fully characterized. A systematic study on the gelation abilities, thermotropic behaviors, aggregated microstructures, and mechanical properties of self‐assembled organogels was performed to elucidate the halogen‐substituent effects on their organogelation propensity. It was found that the exact halogen substitutions on the periphery of dendrons exert a profound effect on the organogelation propensity, and dendrons G n ‐Cl (n=2, 3) and G2‐I proved to be highly efficient organogelators. The cooperation of multiple π–π, dispersive halogen, CH–π, and weak C?H ??? X hydrogen‐bonding interactions were found to be the key contributor to forming the self‐assembled gels. Dendritic organogels formed from G n ‐Cl (n=2, 3) in 1,2‐dichloroethane exhibited thixotropic‐responsive properties, and such thixotropic organogels are promising materials for future research and applications. 相似文献
139.
Biao Ma Peng Wu Xing Wang Zhengyu Wang Hai‐Xia Lin Hui‐Xiong Dai 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(38):13469-13473
A rhodium(III)‐catalyzed domino annulation of simple olefins with diazo oxindoles to give spirooxindole pyrrolone products is described. This reaction can be formally viewed as the result of an anomalous tandem C?H activation, carbene insertion, Lossen rearrangement, and a nucleophilic addition process. The potential utility of this reaction was further demonstrated by the late‐stage diversification of drug molecules. 相似文献
140.