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921.
Pullin等人曾对全氟碘代烷与三级胺的相互作用进行了研究,发现R_(?)I与NR_3能形成电荷转移络合物,即:R_(?)…I…NR_3。但此后却未见到有关反应的报道。我们发现在钯催化剂存在下,全氟碘化物与三乙胺能发生反应,反应条件较为温和,产物为氟代烷基烯基二乙基胺1。反应可能是在三乙胺中先产生一个双键,然后β碳原子接上一个全氟烷基。1的IR和NMR与Blanc报道的一致。化合物1经水解可得胺基烯酮2。在酸溶液中水解时,速度明显加快,而在碱溶液中,不仅不能加快水解速度,而且还有副反应发生。我们对化合物2进 相似文献
922.
Peiguang Zhou H. L. Frisch L. Rogovina L. Makarova A. Zhdanov N. Sergeienko 《Journal of polymer science. Part A, Polymer chemistry》1993,31(10):2481-2491
Simultaneous IPNs of poly(dimethyl siloxane-urethane) (PDMSU)/poly(methyl methacrylate) (PMMA) and related isomers have been prepared by using new oligomers of bis(β-hydroxyethoxymethyl)poly(dimethyl siloxane)s (PDMS diols) and new crosslinkers biuret triisocyanate (BTI) and tris(β-hydroxylethoxymethyl dimethylsiloxy) phenylsilane (Si-triol). Their phase morphology have been characterized by DSC and SEM. The SEM phase domain size is decreased by increasing crosslink density of the PDMSU network. A single phase IPN of PDMSU/PMMA can be made at an Mc = 1000 and 80 wt % of PDMSU. All of the pseudo- or semi-IPNs and blends of PDMSU and PMMA were phase separated with phase domain sizes ranging from 0.2 to several micrometers. The full IPNs of PDMSU/PMMA have better thermal resistance compared to the blends of linear PDMSU and linear PMMA. © 1993 John Wiley & Sons, Inc. 相似文献
923.
924.
Dr. Fang Hu Guobin Qi Dr. Kenry Dr. Duo Mao Dr. Shiwei Zhou Dr. Min Wu Dr. Wenbo Wu Prof. Bin Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(24):9374-9378
Protected by the host cells, the hidden intracellular bacteria are typically difficult to kill by common antibiotics and cannot be visualized without complex cellular pretreatments. Herein, we successfully developed a bacteria-metabolizable dual-functional probe TPEPy-d -Ala, which is based on d -alanine and a photosensitizer with aggregation-induced emission for fluorescence turn-on imaging of intracellular bacteria in living host cells and photodynamic ablation in situ. Once metabolically incorporated into bacterial peptidoglycan, the intramolecular motions of TPEPy-d -Ala are inhibited, leading to an enhanced fluorescent signal, which allows the clear visualization of the intracellular bacteria. Moreover, TPEPy-d -Ala can effectively ablate the labeled intracellular bacteria in situ owing to covalent ligation to peptidoglycan, yielding a low intracellular minimum inhibitory concentration (MIC) of 20±0.5 μg mL−1, much more efficient than that of a commonly used antibiotic, vancomycin. 相似文献
925.
Shenghan Teng Dr. Zhiwei Jiao Prof. Dr. Yonggui Robin Chi Prof. Dr. Jianrong Steve Zhou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(6):2266-2270
Palladium-catalyzed three-component carboetherification of cyclic alkenes proceeded to give trans adducts exclusively with excellent enantioselectivity through a Wacker-type pathway. The reaction is also applicable to other oxygen nucleophiles, such as water, phenols, and carboxylic acids, as well as some electron-poor aryl amines. 相似文献
926.
Yuting Wang Dr. Wei Zhou Ranran Jia Prof. Yifu Yu Prof. Bin Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(13):5388-5392
Unveiling the active phase of catalytic materials under reaction conditions is important for the construction of efficient electrocatalysts for selective nitrate reduction to ammonia. The origin of the prominent activity enhancement for CuO (Faradaic efficiency: 95.8 %, Selectivity: 81.2 %) toward selective nitrate electroreduction to ammonia was probed. 15N isotope labeling experiments showed that ammonia originated from nitrate reduction. 1H NMR spectroscopy and colorimetric methods were performed to quantify ammonia. In situ Raman and ex situ experiments revealed that CuO was electrochemically converted into Cu/Cu2O, which serves as an active phase. The combined results of online differential electrochemical mass spectrometry (DEMS) and DFT calculations demonstrated that the electron transfer from Cu2O to Cu at the interface could facilitate the formation of *NOH intermediate and suppress the hydrogen evolution reaction, leading to high selectivity and Faradaic efficiency. 相似文献
927.
Wang Zhongping Zhao Yating Zhou Long Xu Linglin Diao Guizhi Liu Guanghua 《Journal of Thermal Analysis and Calorimetry》2020,140(2):545-553
Journal of Thermal Analysis and Calorimetry - Aluminate containing phases such as tricalcium aluminate (C3A) and dodecacalcium heptaaluminate (C12A7) play a key role in the reaction between... 相似文献
928.
Long Chen Hanrui Zhang Shengnan Liu Chenghua Sun Xiujie Hu Shuyun Zhou 《Surface and interface analysis : SIA》2020,52(7):389-395
Designed growth of zinc oxide (ZnO)/poly(3,4-ethylenedioxythiophene) (PEDOT) core/shell hybrid nanotube arrays has been achieved by electropolymerization technique. The ZnO/PEDOT hybrid nanotubes electropolymerized for 2000-second display enhanced electrochromic properties of the contrast ratio up to 31.3%, a lot higher than those of the pure PEDOT and ZnO/PEDOT hybrid nanorods. Moreover, the coloring efficiency of the hybrid nanotubes increases from 105.2 cm2 C−1 of ZnO/PEDOT hybrid nantotube with the electrodeposition time of 1000 seconds to 122.2 cm2 C−1 of 2000 seconds at 520 nm. Therefore, the hybrid composite nanotubes fabricated by the in situ electrodeposition techniques may demonstrate huge potential applications in energy-saving technologies such as smart windows. 相似文献
929.
葡萄糖在KRPB生理缓冲溶液中电还原反应的研究 总被引:1,自引:0,他引:1
葡萄糖在KRPB生理缓冲溶液中电还原反应的研究朱庆存,姜力夫,郁章玉,陈常峰,周正宇(曲阜师范大学,电化学研究所,曲阜273165)关键词:葡萄糖,扩散系数,磷酸盐生理溶液。本文从葡萄糖在铂电极上的电氧化还原峰电流与pH值的线性关系,扩散系数与葡萄糖... 相似文献
930.
Daoyong Zhu Zhiwei Jiao Yonggui Robin Chi Tho P. Gonalves Kuo‐Wei Huang Jianrong Steve Zhou 《Angewandte Chemie (International ed. in English)》2020,59(13):5341-5345
Substituted cyclohexylamines are becoming increasingly important in drug discovery. Asymmetric Heck insertion/amination of nonconjugated cyclodienes proceeds to give 5‐aryl cyclohexenylamines with good enantioselectivity and exclusive trans configurations. Primary and secondary anilines, indoline, and benzylamines are suitable amines. The weakly donating diphosphite Kelliphite forms a deep unsymmetrical pocket, which is essential for stereoselective anti attack of amines. 相似文献