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81.
基于超分子结构共掺杂纳米复合薄膜的制备与荧光特性 总被引:5,自引:0,他引:5
为改善功能分了的特性,提出一种基于金属纳米粒子-偶氮染料复合物共掺杂超分子结构功能材料的设计新方法.并依照此方法制备出复合材料,观测了其显微结构,测量了其紫外-可见光吸收,研究了该超分子结构复合体系的荧光特性.实验发现,由于金属银纳米粒子的掺杂,使得超分子结构复合体系中功能分子甲基橙在溶液态体系的荧光强度增强近5倍,而在两种不同结构(共混结构和包覆结构)的薄膜态超分子结构体系中,其荧光强度分别被猝灭15%和20%.研究结果表明,复合膜中采用超分子结构完全能够改善功能分子的特性. 相似文献
82.
Ecaterina Stela Dragan Marcela Mihai Anton Airinei 《Journal of polymer science. Part A, Polymer chemistry》2006,44(20):5898-5908
The thermochemical transformation of electrostatically formed complexes of methyl orange (MO) with polycations containing primary amine groups such as ammonium salts afforded new polymers with a high concentration of covalently bound 4‐N,N‐dimethylaminoazobenzene groups in the side chain. Poly(allylamine hydrochloride) and poly(β‐aminoethylene acrylamide hydrochloride) were employed as support polycations for MO. The transformation of sulfonate–ammonium ion pairs into sulfonamide bonds, via heating at an elevated temperature, was supported by the polymer properties before and after the thermal treatment. The polymer structure changes were monitored with elemental analysis, Fourier transform infrared, 1H NMR, and ultraviolet–visible absorption spectroscopy, and thermogravimetric analysis. The spacer length between the backbone and azobenzene structures used as side chains strongly influenced the polymer properties before and after the heat‐induced reaction. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5898–5908, 2006 相似文献
83.
Xiao Qi ZHENG Yong Hui WANG Qing Xiang GUO* Li YANG You Cheng LIU Department of Chemistry University of Science Technology of China Hefei National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 《中国化学快报》2003,(8)
As artificial enzymes, the binding constants of cyclodextrins (CDs) and their substrates are expected to be high1. For this purpose, many kinds of bridged cyclodextrin dimers2 whose two cyclodextrins are linked by various spacers have been constructed. It was of interest to make the dimers, whose binding constants would exceed 108dm3/mol3. Up to date, the bridged cyclodextrin dimers have been extensively studied as enzyme models and as molecular receptors4-6. Recently, we synthesized a brid… 相似文献
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87.
磁性碳纳米管吸附去除水中甲基橙的研究 总被引:1,自引:0,他引:1
采用高温催化裂解法制备碳纳米管,对其用浓硝酸氧化法进行纯化处理,并用化学共沉淀方法制备了磁性碳纳米管(简称磁性管)。利用场发射扫描电子显微镜对磁性管进行了表征。将磁分离技术应用于碳纳米管吸附性能研究,探索碳纳米管负载磁性颗粒后对甲基橙的吸附性能,寻找最佳实验条件,对吸附质溶液进行紫外-可见吸收光谱分析。同时,进行了磁性管的脱附和再吸附性能研究。 相似文献
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Lab-on-valve for the automatic determination of the total content and individual profiles of linear alkylbenzene sulfonates in water samples 总被引:1,自引:0,他引:1
Methods for the total content and individual determination of linear alkylbenzene sulfonates (LAS) in water samples based on the use of a lab-on-valve (LOV) module alone or coupled to CE equipment, respectively, have been developed. The total content of LAS has been determined by intrinsic absorption measurements (DA method) and after reaction with a methyl orange-cetylpyridine chloride mixture (MO method) with detection limits (LODs) of 21 ng/L and 15 microg/L, respectively, quantification limits (LOQs) of 70 ng/L, 50 microg/L, and development times of 100 and 124 s, respectively. The method for individual separation-quantification of LAS at very low concentration is based on automatic SPE preconcentration in the LOV module coupled on-line with the CE equipment. The LODs and LOQs thus obtained range between 1-21 and 4-70 ng/L, respectively, with linear dynamic ranges from the LOQ to 10 microg/L. Preconcentration factors of 10,000 and high efficiency to eliminate interferents by SPE enable application of the method to treated effluent, waste, surface and sea waters. 相似文献
90.
M. F. Budyka G. V. Zakharova O. D. Laukhina M. V. Alfimov 《Russian Chemical Bulletin》1992,41(9):1589-1596
The reaction of the photochemical synthesis of 2,7-dimethylacridine from di(para-tolyl)amine and bromoform was studied utilizing the method of microsecond impulse photolysis. The proposed new scheme for the formation of acridine assumes the recombination of the primary alkyl radicals at the nitrogen atom of the cation radical and/or the radical of the amine as the main route of the reaction. The data obtained indicate the common character of the nature of some intermediate stages and the structures of the intermediates in the photochemical formation of acridine compounds and triphenylmethane dyes from aromatic amines and halogenomethanes.Institute of Chemical Physics, Chernogolovka, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 9, pp. 2044–2052, September, 1992. 相似文献