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Capillary electrophoretic studies on quantum dots and histidine appended peptides self‐assembly 下载免费PDF全文
Jianhao Wang Jingyan Li Yao Chen Yiwan Teng Cheli Wang Jinchen Li Li Liu Bingyu Dong Lin Qiu Pengju Jiang 《Electrophoresis》2015,36(19):2419-2424
Herein, we designed four peptides appended with different numbers of histidine (Hisn‐peptide). We launched a systematic investigation on quantum dots (QDs) and Hisn‐peptide self‐assembly in solution using fluorescence coupled CE (CE‐FL). The results indicated that CE‐FL was a powerful method to probe how ligands interaction on the surface of nanoparticles. The self‐assembly of QDs and peptide was determined by the numbers of histidine. We also observed that longer polyhistidine tags (n ≤ 6) could improve the self‐assembly efficiency. Furthermore, the formation and separation of QD‐peptide assembly were also studied by CE‐FL inside a capillary. The total time for the mixing, self‐assembly, separation, and detection was less than 10 min. Our method greatly expands the application of CE‐FL in QDs‐based biolabeling and bioanalysis. 相似文献
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Fan-Ying Wu Qi-Yi Wu Chen Zhang Yang Luo Xiangqi Liu Yuan-Feng Xu Dong-Hui Lu Makoto Hashimoto Hao Liu Yin-Zou Zhao Jiao-Jiao Song Ya-Hua Yuan Hai-Yun Liu Jun He Yu-Xia Duan Yan-Feng Guo Jian-Qiao Meng 《Frontiers of Physics》2023,18(5):53304
The three-dimensional electronic structure and the nature of Ce 4f electrons of the Kondo insulator CeRu4Sn6 are investigated by angle-resolved photoemission spectroscopy, utilizing tunable photon energies. Our results reveal (i) the three-dimensional k-space nature of the Fermi surface, (ii) the localized-to-itinerant transition of f electrons occurs at a much high temperature than the hybridization gap opening temperature, and (iii) the “relocalization” of itinerant f-electrons below 25 K, which could be the precursor to the establishment of magnetic order. 相似文献
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圆偏振发光主要是指手性发光体系激发态的性质。由于其在信息加密、高分辨3D显示和智能传感器等领域的潜在应用而备受关注。圆偏振光除了可以通过物理方法获得,即使用线偏振片和四分之一波片的组合,还可以直接从具有光致发光或电致发光性质的手性材料中获得。目前研究者们已经开发了多种圆偏振发光材料,主要包括手性有机分子、手性金属配合物等小分子发光体系以及手性超分子组装体等复合体系。通过将手性组分与响应性功能基团结合而构筑的响应性自组装发光体系对实现智能圆偏振发光材料的发展起着重要作用。在这篇文章里,我们对手性超分子自组装发光体系对各种外界刺激的响应性能进行了总结和归纳,如光照、pH值、溶剂、温度、金属离子等。本综述通过对各种外部刺激对手性组装体激发态性能影响的总结和讨论,旨在进一步推动智能圆偏振发光材料在多学科领域的应用。 相似文献
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In this study, a series of tetrafluoroborates with non-π-conjugated [BF4] tetrahedra are investigated systematically by first-principles calculations. Theoretical studies demonstrate that tetrafluoroborates with alkali and/or alkaline-earth metals are more favorable for deep-ultraviolet transmission and are comparable to the classical deep-ultraviolet (deep-UV) material, MgF2. Furthermore, bandgap decrease with the increasing of ionic radii in alkali and/or alkaline-earth metals. Introducing highly polarizable cations with d10-configuration or cations with lone pair electrons into the structure will decrease the bandgaps. The birefringence and second harmonic generation effects are not large enough in tetrafluoroborates because polarizability anisotropy and hyperpolarizability in non-π-conjugated [BF4] tetrahedra are much smaller than those in π-conjugated groups. However, the second harmonic generation effect for [BF4] tetrahedra has a higher contribution in comparison with that due to birefringence. To effectively synthesize the borate fluorides or fluorooxoborates in the deep-UV region, raw materials with B−F bonds are preferred. 相似文献
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Ning Zuozhou Zhang Zhicheng Yan Qingsong Zhou Naifu Wen Linzi Peng Xichao Tang Yu Feng Pengju 《中国科学:化学(英文版)》2022,65(10):1962-1967
Science China Chemistry - A mild and practical protocol for selectively time-dependent dehydrogenative C-C coupling, as well as tandem coupling-cyclization reaction between indoles or/and other... 相似文献
59.
Xiaokang Li Jianqiao Li Chunyu Ma Siqi Zhang Bin Tu Wubiao Duan Qingdao Zeng 《中国化学快报》2021,32(3):1077-1080
Here,the selective adsorption behaviors of guest molecule COR in two hexamer host grids were investigated by means of scanning tunnelling microscope(STM).The assembled structures of small functional organic molecules TTBTA and TATBA were thermodynamically stable.Interestingly,the introduction of the guest molecule COR destroyed the original hexamer structure of TTBTA and combined with it to form a new triangular host-guest system.Different from TTBTA,the introduction of the guest molecule COR did not affect the six-membered ring structure of TATBA.Furthermore,the co-assembly structure of TTBTA/TATBA/COR was established and the guest molecule COR showed preferential adsorption to the TATBA host grid.Density functional theory(DFT) calculations had been performed to disclose the mechanism of the involved assemblies. 相似文献
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An improved and practical synthesis of enzalutamide was accomplished in five steps. Starting from 4-bromo-2-fluoro-benzonic acid, a methyl esterification, Ullmann ligation, methyl esterification, ring closing reaction and final methyl amidation provided the target in 35% total yield with 99.8% purity. Five identified impurities were also synthesized. This efficient and economical procedure avoids the use of highly toxic reagents and multiple recrystallization operations, which is suitable for further industrialization. 相似文献