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Given facile synthetic route and excellent photo stability, excited state intramolecular proton transfer (ESIPT)-active luminous materials have gained more and more attention. Here, we focus on photo-induced excitation process and the ESIPT reaction process for the novel 5-benzothiazol-2-yl-6-hydroxy-2-methyl-isoindole-1,3-dione (HPIBT) molecule. On the level of chemical geometries and infrared spectra, we verify that O─H⋯N of HPIBT should be enhanced. We find that a proton is likely to be attracted by enhanced electronic densities around N, that is, charge transfer impetus ESIPT trend. Combing potential energy curves and searching for transition state, we clarify the ultrafast ESIPT mechanism of HPIBT due to a low barrier, which legitimately explains previous experimental characteristics. 相似文献
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Shengda Wang Xingcheng Li Xinyu Zhang Pingsen Huang Pengwei Fang Junhui Wang Shangfeng Yang Kaifeng Wu Pingwu Du 《Chemical science》2021,12(31):10506
Herein, we design and synthesize a novel all-carbon supramolecular polymer host (SPh) containing conjugated macrocycles interconnected by a linear poly(para-phenylene) backbone. Applying the supramolecular host and fullerene C60 as the guest, we successfully construct a supramolecular polymeric heterojunction (SPh⊃C60). This carbon structure offers a means to explore the convex–concave π–π interactions between SPh and C60. The produced SPh was characterized by gel permeation chromatography, mass spectrometry, FTIR, Raman spectroscopy, and other spectroscopies. The polymeric segment can be directly viewed using a scanning tunneling microscope. Femtosecond transient absorption and fluorescence up-conversion measurements revealed femtosecond (≪300 fs) electron transfer from photoexcited SPh to C60, followed by nanosecond charge recombination to produce the C60 triplet excited state. The potential applications of SPh⊃C60 in electron- and hole-transport devices were also investigated, revealing that C60 incorporation enhances the charge transport properties of SPh. These results expand the scope of the synthesis and application of supramolecular polymeric heterojunctions.Herein, we design and synthesize a novel all-carbon supramolecular polymer host (SPh) containing conjugated macrocycles interconnected by a linear poly(para-phenylene) backbone. 相似文献
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Cellulose - It remains a formidable challenge to construct high-performance haemoperfusion adsorbents with fast adsorption kinetic and high adsorption capacity for efficiently removing bilirubin... 相似文献
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The wax deposition rate of water-in-crude oil emulsions based on the laboratory flow loop experiment
This paper aims to develop a mathematical model to predict the wax deposition rate of waxy crude emulsions, combining heat and mass transfer mechanisms. According to the flow loop experimental results, the wax deposition rate increases with the decreasing average temperature of oil/wall in a manner of linear regularity, and shows a downtrend with the increase of water cut due to diffusion resistance. An applicable model is developed regarding emulsion properties, radial temperature gradient, shear stress, and wax diffusion coefficient. In model validation, the prediction results are in good agreement with experimental data with the relative errors within 28.87%. 相似文献
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采用Mindlin壳元,对SPF/DB工艺进行了模拟。利用罚函数方法,对板材自身接触问题进行分析,给出了接触板材间的接触力,并提出一种接触搜索判断方法,同时给出了算例。 相似文献
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Tandem Radical Cyclization for the Construction of Difluoro‐Containing Oxindoles and Quinoline‐2,4‐diones
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Fangwei Ding Yuanding Fang Yanqiu Jiang Prof. Dr. Kaifeng Lin Prof. Lei Shi 《化学:亚洲杂志》2018,13(6):636-640
Cu‐catalyzed direct difluoromethylation of activated alkenes through a difluoromethyl radical addition/cyclization to afford difluorinated oxindoles and quinoline‐2,4‐diones has been developed. This method provides convenient access to a variety of oxindoles and quinoline‐2,4‐diones under mild conditions via a proposed tandem radical cyclization process, while tolerating various functional groups well. Moreover, a facile method to construct diverse difluorinated quinoline‐2,4‐diones by visible‐light photoredox catalysis under mild conditions was presented. 相似文献
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Li Na Gan Kaifeng Lu Deli Zhang Jinlong Wang Lingzhi 《Research on Chemical Intermediates》2018,44(2):1105-1117
Research on Chemical Intermediates - A three-dimensionally macroporous–mesoporous lithium ion sieve (3DM-H4Ti5O12) was transformed from 3DM-Li4Ti5O12 through washing with HCl solution, which... 相似文献
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Abstract In this article, we extend the definition of uniformly starlike functions and uni- formly convex functions on the unit disk to the unit ball in C^n, give the discriminant criterions for them, and get some inequalities for them. 相似文献