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991.
An asymmetrical perylene diimide 3, N-(4-methoxyphenyl)-N'-(4-nitrophenyl)-perylene-3,4,9,10-tetracarboxylic diimide, was synthesized, and its self-assembly and dissociation behaviors in chloroform was studied in detail by UV-vis and fluorescence spectroscopies. The resulting unique helical nanostructures from 3 were proposed to be self-assembled via the cooperative actions of π-π stacking, steric hindrance and electrophile-nucleophile type pairing. 相似文献
992.
993.
994.
Bingjie Liu Shuoxuan Wang He Wang Yong Wang Yin Xiao Yue Cheng 《Molecules (Basel, Switzerland)》2023,28(1)
Water recovery is a significant proposition for human survival and sustainable development, and we never stop searching for more efficient, easy-operating, low-cost and environmentally friendly methods to decontaminate water bodies. Herein, we combined the advantages of β-cyclodextrin (β-CD), magnetite nanoparticles (MNs), and two kinds of quaternary ammonium salts to synthesize two porous quaternary ammonium groups capped magnetic β-CD polymers (QMCDP1 and QMCDP2) to remove organic pollutants and eradicate pathogenic microorganisms effectively through a single implementation. In this setting, β-CD polymer (CDP) was utilized as the porous substrate material, while MNs endowed the materials with excellent magnetism enhancing recyclability in practical application scenarios, and the grafting of quaternary ammonium groups was beneficial for the adsorption of anionic dyes and sterilization. Both QMCDPs outperformed uncapped MCDPs in their adsorption ability of anionic pollutants, using methyl blue (MB) and orange G (OG) as model dyes. Additionally, QMCDP2, which was modified with longer alkyl chains than QMCDP1, exhibits superior bactericidal efficacy with a 99.47% removal rate for Staphylococcus aureus. Accordingly, this study provides some insights into designing a well-performed and easily recyclable adsorbent for simultaneous sterilization and adsorption of organic contaminants in wastewater. 相似文献
995.
本文测定了八个照相染料在不同pH条件下的还原电位。发现其中一些增感染料的还原电位与其溶液的pH值无关,而一些减感染料依赖于pH值的变化。本文用染料质子化机理分析了这些结果。 相似文献
996.
997.
《中国化学会会志》2017,64(11):1333-1339
The degradation of organic dyes in the presence of modified TiO2 is still under intensive investigation. We report here an evaluation of the photocatalytic activity of nitrogen‐ (N‐) and sulfur‐ (S‐) doped TiO2 for the degradation of phenol and methylene blue (MB). N‐doped TiO2 (N–TiO2), S‐doped TiO2 (S–TiO2), and N–S‐doped TiO2 (N–S–TiO2) were prepared using the sol–gel method. The photocatalytic activity was evaluated in a batch reactor using phenol and MB as models of pollutants. In addition, this investigation was performed using a household lamp as the visible light source. Properties of the synthesized materials in terms of Brunauer–Emmett–Teller (BET) surface analysis, field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), and photocatalytic ability were examined. Our study shows that N–S–TiO2 exhibits better photocatalytic degradation ability for all the considered dyes compared to the other doped TiO2 materials. In conclusion, we have successfully prepared and evaluated the photocatalytic activity of N‐ and S‐doped TiO2 for the degradation of phenol and MB using an ordinary household lamp. 相似文献
998.
《化学:亚洲杂志》2017,12(17):2177-2182
We theoretically predicted that acetylene‐bridged benzo[1,2‐c ;4,5‐c ′]bis[1,2,5]thiadiazole (BBT) oligomers would show a quick increase of diradical character with the extension of chain length. To validate the hypothesis, six stable BBT‐based diradicaloids were synthesized and fully characterized by X‐ray crystallographic analysis and various spectroscopic measurements. Three of them showed prominent paramagnetic activity at elevated temperatures due to thermal population from the open‐shell singlet ground state to triplet excited state. It was also found that substitution by electron‐donating triphenylamine groups at the termini promoted the diradical character and reduced the singlet–triplet energy gap, and at the same time, resulted in intense near‐infrared absorption. 相似文献
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1000.
有机光电导体己在静电复印、全息记录、信息存储等方面得到应用。特别是半导体激光器的研制成功,人们对研究适用于近红外的有机光电导体材料越来越感兴趣,注意发展为特殊体系应用的以颜料为基础的光电导体上。 相似文献