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991.
Ping Xu Ruyue Yuan Guohua Hou Jinglei Li Ming Ye 《Applied biochemistry and biotechnology》2018,185(2):541-554
Exopolysaccharide of Lachnum YM130 (LEP) was purified by diethylaminoethyl cellulose 52 and Sepharose CL-6B column chromatography. LEP-2a was identified to be a homogeneous component with an average molecular weight of 1.31?×?106 Da, which was consisted of mannose and galactose in a molar ratio of 3.8:1.0. The structure of LEP-2a was characterized by methylation analysis, FT-IR analysis, and NMR analysis. Results indicated that LEP-2a was a galactomannan with a backbone, composed of 1,2-linked-α-D-Manp, 1,2,6-linked-α-D-Manp, 1,3,4-linked-α-D-Manp, and 1,3-linked-β-D-Galp, which was substituted at O-2, O-3, O-4, and O-6 by branches. In vitro antitumor activity assay proved that LEP-2a could significantly enhance the inhibitory effectiveness of 5-FU on Hela cells at the concentrations of 100, 200, 300, and 400 μg/mL. The above results suggested that LEP-2a could be seen as a potential source for developing novel antineoplastic agents. 相似文献
992.
Diastereo‐ and Enantioselective Palladium‐Catalyzed Dearomative [3+2] Cycloaddition of 3‐Nitroindoles 下载免费PDF全文
Diastereo‐ and enantioselective cycloaddition of 3‐nitroindoles with vinyl aziridine was realized under Pd‐catalysis using commercially available Walphos as the ligand, affording pyrroloindolines in high yields with high diastereo‐ and enantioselectivities. The reaction can be scaled up to a gram scale and the reaction products are easily converted to amino pyrroloindoline and other pyrroloindoline derivatives. 相似文献
993.
An Unconventional Polymerization Route to Hydrophilic Fluorescent Organic Nanoparticles for Multicolor Cellular Bioimaging 下载免费PDF全文
Qingfu Ban Yinglai Hou Dr. Wen Sun Dr. Jianxin Chen Xiaofei Zhang Dr. Si Wu Prof. Jie Kong 《化学:亚洲杂志》2018,13(12):1625-1631
We demonstrated an unconventional polymerization route to synthesize hydrophilic fluorescent organic nanoparticles (FONs) for multicolor cellular bioimaging in this contribution. The route benefits from our unexpected discovery of a rapid polymerization reaction between 1,6‐hexanediol dipropiolate and 2,4,6‐triazide‐1,3,5‐triazine under the catalysis of N,N,N′,N′′,N′′‐pentamethyldiethylenetriamine (PMDETA). Interestingly, the 2,4,6‐triazide‐1,3,5‐triazine and PMDETA system can also induce rapid free radical polymerization at room temperature. The as‐prepared FONs exhibited promising water solubility and stability with an average diameter of 20 nm. The excitation wavelength‐dependent fluorescent properties endow the FONs with blue, yellow, and red fluorescent emission under UV, blue, and green excitation, respectively. The cytotoxicity of FONs was investigated by using a Cell Counting Kit (CCK‐8) assay, which indicated good biocompatiblity. More importantly, the cell uptake experiment verified the FONs were excellent fluorescent nanoprobes for multicolor cellular bioimaging. Therefore, this unconventional route provides a novel fabrication strategy of highly hydrophilic FONs for biomedical applications. 相似文献
994.
Dr. Xiulin Fan Dr. Fei Wang Dr. Xiao Ji Ruixing Wang Dr. Tao Gao Singyuk Hou Dr. Ji Chen Tao Deng Dr. Xiaogang Li Dr. Long Chen Dr. Chao Luo Luning Wang Prof. Chunsheng Wang 《Angewandte Chemie (International ed. in English)》2018,57(24):7146-7150
Low‐cost multivalent battery chemistries (Mg2+, Al3+) have been extensively investigated for large‐scale energy storage applications. However, their commercialization is plagued by the poor power density and cycle life of cathodes. A universal polyimides@CNT (PI@CNT) cathode is now presented that can reversibly store various cations with different valences (Li+, Mg2+, Al3+) at an extremely fast rate. The ion‐coordination charge storage mechanism of PI@CNT is systemically investigated. Full cells using PI@CNT cathodes and corresponding metal anodes exhibit long cycle life (>10000 cycles), fast kinetics (>20 C), and wide operating temperature range (?40 to 50 °C), making the low‐cost industrial polyimides universal cathodes for different multivalent metal batteries. The stable ion‐coordinated mechanism opens a new foundation for the development of high‐energy and high‐power multivalent batteries. 相似文献
995.
Real‐Time Probing of Nanowire Assembly Kinetics at the Air–Water Interface by In Situ Synchrotron X‐Ray Scattering 下载免费PDF全文
Zhen He Dr. Hui‐Jun Jiang Long‐Long Wu Dr. Jian‐Wei Liu Dr. Geng Wang Xiao Wang Dr. Jin‐Long Wang Prof. Zhong‐Huai Hou Prof. Gang Chen Prof. Shu‐Hong Yu 《Angewandte Chemie (International ed. in English)》2018,57(27):8130-8134
Although many assembly strategies have been used to successfully construct well‐aligned nanowire (NW) assemblies, the understanding of their assembly kinetics has remained elusive, which restricts the development of NW‐based device and circuit fabrication. Now a versatile strategy that combines interfacial assembly and synchrotron‐based grazing‐incidence small‐angle X‐ray scattering (GISAXS) is presented to track the assembly evolution of the NWs in real time. During the interface assembly process, the randomly dispersed NWs gradually aggregate to form small ordered NW‐blocks and finally are constructed into well‐defined NW monolayer driven by the conformation entropy. The NW assembly mechanism can be well revealed by the thermodynamic analysis and large‐scale molecular dynamics theoretical evaluation. These findings point to new opportunities for understanding NW assembly kinetics and manipulating NW assembled structures by bottom‐up strategy. 相似文献
996.
Enantioselective Construction of Silicon‐Stereogenic Silanes by Scandium‐Catalyzed Intermolecular Alkene Hydrosilylation 下载免费PDF全文
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
997.
Cross‐Linked Aptamer–Lipid Micelles for Excellent Stability and Specificity in Target‐Cell Recognition 下载免费PDF全文
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
998.
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
999.
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
1000.
Direct Observation of Transition Metal Dichalcogenides in Liquid with Scanning Tunneling Microscopy 下载免费PDF全文
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