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961.
Enantioselective Construction of Silicon‐Stereogenic Silanes by Scandium‐Catalyzed Intermolecular Alkene Hydrosilylation
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Dr. Gu Zhan Dr. Huai‐Long Teng Dr. Yong Luo Dr. Shao‐Jie Lou Dr. Masayoshi Nishiura Prof. Dr. Zhaomin Hou 《Angewandte Chemie (International ed. in English)》2018,57(38):12342-12346
The catalytic asymmetric construction of silicon‐stereogenic silanes is of great interest and significance, but has met with only limited success to date. We herein report the enantioselective hydrosilylation of alkenes with dihydrosilanes by a chiral half‐sandwich scandium catalyst, which constitutes an efficient and general route for the synthesis of a wide range of enantioenriched silicon‐stereogenic silanes from easily accessible starting materials. This reaction features a broad substrate scope, high yields, and high enantioselectivity. Some of the chiral tertiary silane products were also converted into valuable derivatives, such as chiral silanol, quaternary silane, and benzosilole compounds. 相似文献
962.
Cross‐Linked Aptamer–Lipid Micelles for Excellent Stability and Specificity in Target‐Cell Recognition
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Xiaowei Li Dr. C. Adrian Figg Dr. Ruowen Wang Dr. Ying Jiang Dr. Yifan Lyu Hao Sun Dr. Yuan Liu Dr. Yanyue Wang Dr. I‐Ting Teng Dr. Weijia Hou Dr. Ren Cai Dr. Cheng Cui Long Li Xiaoshu Pan Prof. Brent S. Sumerlin Prof. Weihong Tan 《Angewandte Chemie (International ed. in English)》2018,57(36):11589-11593
The specific binding ability of DNA–lipid micelles (DLMs) can be increased by the introduction of an aptamer. However, supramolecular micellar structures based on self‐assemblies of amphiphilic DLMs are expected to demonstrate low stability when interacting with cell membranes under certain conditions, which could lead to a reduction in selectivity for targeting cancer cells. We herein report a straightforward cross‐linking strategy that relies on a methacrylamide branch to link aptamer and lipid segments. By an efficient photoinduced polymerization process, covalently linked aptamer–lipid units help stabilize the micelle structure and enhance aptamer probe stability, further improving the targeting ability of the resulting nanoassembly. Besides the development of a facile cross‐linking method, this study clarifies the relationship between aptamer–lipid concentration and the corresponding binding ability. 相似文献
963.
Hou Pengkun Li Ran Li Haoting Xie Ning Cheng Xin Singh L. P. 《Journal of Thermal Analysis and Calorimetry》2018,134(3):1775-1784
Journal of Thermal Analysis and Calorimetry - The durability of cement-based materials can be significantly improved by surface treatment with organic or inorganic silica-based treatment agents. In... 相似文献
964.
Dr. Jue Hou Prof. Dr. Mingzhu Li Prof. Dr. Yanlin Song 《Angewandte Chemie (International ed. in English)》2018,57(10):2544-2553
Colloidal photonic crystals (PCs) have been well developed because they are easy to prepare, cost‐effective, and versatile with regards to modification and functionalization. Patterned colloidal PCs contribute a novel approach to constructing high‐performance PC devices with unique structures and specific functions. In this review, an overview of the strategies for fabricating patterned colloidal PCs, including patterned substrate‐induced assembly, inkjet printing, and selective immobilization and modification, is presented. The advantages of patterned PC devices are also discussed in detail, for example, improved detection sensitivity and response speed of the sensors, control over the flow direction and wicking rate of microfluidic channels, recognition of cross‐reactive molecules through an array‐patterned microchip, fabrication of display devices with tunable patterns, well‐arranged RGB units, and wide viewing‐angles, and the ability to construct anti‐counterfeiting devices with different security strategies. Finally, the perspective of future developments and challenges is presented. 相似文献
965.
Direct Observation of Transition Metal Dichalcogenides in Liquid with Scanning Tunneling Microscopy
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Ze Wang Ji-hao Wang Wei-feng Ge Wen-jie Meng Jing Zhang Qi-yuan Feng Yu-bin Hou Qing-you Lu 《化学物理学报(中文版)》2018,31(6):767-771
We present atomic-resolution images of TiSe\begin{document}$_2$\end{document} , MoTe\begin{document}$_2$\end{document} and TaS\begin{document}$_2$\end{document} single crystals in liquid condition using our home-built scanning tunneling microscopy (STM). By facilely cleaving of single crystals in liquid, we were able to keep the fresh surface not oxidized within a few hours. Using the high-stable home-built STM, we have obtained atomic resolution images of TiSe\begin{document}$_2$\end{document} accompanied with the single atom defects as well as the triangle defects in solution for the first time. Besides, the superstructure of MoTe\begin{document}$_2$\end{document} and hexagonal charge-density wave domain structure in nearly commensurate phase of TaS\begin{document}$_2$\end{document} were also obtained at room temperature (295 K). Our results provide a more efficient method in investigating the lively surface of transition metal dichalcogenides. Besides, the high stable liquid-phase STM will support the further investigations in liquid-phase catalysis or electrochemistry. 相似文献
966.
Hypersurfaces in a sphere with constant mean curvature 总被引:13,自引:0,他引:13
Zhong Hua Hou 《Proceedings of the American Mathematical Society》1997,125(4):1193-1196
Let be a closed hypersurface of constant mean curvature immersed in the unit sphere . Denote by the square of the length of its second fundamental form. If , is a small hypersphere in . We also characterize all with .
967.
The chiral phosphine-containing palladacycle, synthesized easily from H-MOP, showed its high catalytic activity as well as asymmetric induction ability in ring-opening reaction of oxabicyclic alkenes with arylboronic acids, providing corresponding products in high yields and high ee. 相似文献
968.
Single-crystalline KNbO(3) nanocubes with orthorhombic phase were prepared in a large scale by a simple one-step molten salt route without using any surfactant as template; the nanostructures exhibited high piezoelectric properties such as d(33)=105 pC/N and k(p)=0.34 as piezoelectric materials. 相似文献
969.
970.