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Diversified 1,4,5-substituted-2-aminoimidazoles were rapidly assembled via sequential N–H insertion and Grignard addition to α-diazoesters. Lead compounds were identified as antibiotics against Gram-positive bacteria with an MIC value as low as 2 μg/mL. 相似文献
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Polyaniline doped with camphor sulfonic acid, poly(2,5-dimethoxyaniline) and their copolymers were synthesized by interfacial method. The FT-IR spectra, UV-Vis absorption spectra and X-ray diffraction patterns were used to characterize the molecular structures of the polymers. The morphology of the polymers was studied by using SEM and TEM. Voltammetric study was done to investigate the electrochemical behavior of these polymers. The results show that the polymers were in microscale with the different shapes such as rod, flake and sphere, respectively. All the homopolymers and copolymers had a poor crystallinity. The conductivity of the copolymers of aniline with 2,5-dimethoxyaniline decreased with increase of 2,5-dimethoxy-aniline molar content. 相似文献
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Copolyphenylenes with pendant benzimidazolyl and diethanolaminohexyloxy groups: Synthesis and electron‐transporting application in PLEDs
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Chih‐Yang Tseng Wen‐Fen Su Yun Chen 《Journal of polymer science. Part A, Polymer chemistry》2017,55(15):2494-2505
Two new electron‐transporting copolyphenylenes P1NH and P2NH possessing balanced charges crucial to emission efficiency of polymer light‐emitting diodes (PLEDs) have been synthesized and applied as an electron‐transporting layer (ETL). The main chain structure is all para‐linkage for P1NH and both para‐ and meta‐linkage for P2NH , with the same pendant electron‐withdrawing benzimidazolyl and polar diethanolaminohexyloxy groups. Both copolymers possess excellent thermal stability (T d > 300 °C, T g > 100 °C) due to their rigid backbones. In addition, the pendant groups effectively lower LUMO (~ ?2.70 eV) and HOMO (~ ?5.70 eV) levels, resulting in improved electron‐transporting and hole‐blocking capabilities. Multilayer yellow‐emitting PLEDs with a configuration of ITO/PEDOT:PSS/SY/ETL/LiF/Al were successfully fabricated by the spin‐coating process. The maximum luminance and maximum current efficiency of the P1NH ‐based device were 12,881 cd/m2 and 10.94 cd/A, respectively, superior to the performance of P2NH ‐based device (4938 cd/m2, 3.70 cd/A) and the device without ETL (8690 cd/m2, 2.78 cd/A). Current results indicate that P1NH is highly effective in enhancing electron transport and device performance. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 2494–2505 相似文献
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Enzyme Immobilization: Structural Insight into Stabilization of Pickering Emulsions with Fe3O4@SiO2 Nanoparticles for Enzyme Catalysis in Organic Media (Part. Part. Syst. Charact. 7/2017)
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Anzhou Yang Jingchun Wang Keying Su Wu Lei Xiaoyu Qiu Yawen Tang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(15):4869-4875
The surface hydroxyl groups of NixCu1−x(OH)2 play a crucial role in governing their conversion efficiency into NixCu1−xOx(OH)2−x during the electro-chemical pre-activation process, thus affecting the integral ammonia oxidation reaction (AOR) reactivity. Herein, the rational design of hierarchical porous NiCu double hydroxide nanotyres (NiCu DHTs) was reported for the first time by considering hydroxyl-rich interfaces to promote pre-activation efficiency and intrinsic structural superiority (i.e., annulus, porosity) to accelerate AOR kinetics. A systematic investigation of the structure–function relationship was conducted by manipulating a series of NiCu DHs with tunable intercalations and morphologies. Remarkably, the NiCu DHTs exhibit superior AOR activity (onset potential of 1.31 V with 7.52 mA cm−2 at 1.5 V) and high ammonia sensitivity (detection limit of 9 μm ), manifesting one of the best non-noble metal AOR electrocatalysts and electro-analytical electrodetectors. This work deepens the understanding of the crucial role of surface hydroxyl groups on determining the catalytic performance in alkaline medium. 相似文献