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901.
The traditional surfactant sodium dodecyl sulfate (SDS) and ionic liquid 1-ethyl-3-methylimidazolium tetrafluoroborate ([Emim][BF4]) have been combined to create a novel efficient medium for chromogenic catalysis of 3,3',5,5'-tetramethylbenzidine with horseradish peroxidase in presence of H2O2. The results have shown the [Emim][BF4] in the mediums can promote the rate of formation of the blue chromogen, the SDS is responsible for the stabilization of the blue chromogen due to the electrostatic attraction between positively charged blue chromogen and the negatively charged surfactant. The SDS/[Emim][BF4] combination not only enhance catalytic activity of HRP remarkably but also stabilize the blue chromogen formed in the HRP oxidation of the substrate TMB compared to the conventional medium. Based on the superior combination of SDS and [Emim][BF4], the colorimetric assay for detecting HRP activity and H2O2 concentration was established. This work demonstrates a novel efficient medium for chromogenic catalysis with potential applications in biosensors and clinical diagnosis. 相似文献
902.
903.
Simple scaling laws for the design parameters of plasma wakefield accelerators were obtained using a theoretical model, which were confirmed via particle simulation studies. It was found that the acceleration length was given by Δx=0.804λp/(1−βg), where λp is the plasma wavelength and βgc the propagation velocity of the ion cavity. The acceleration energy can also be given by ΔE=(γm−1)mc2=2.645mc2/(1−βg), where m is the electron rest mass. As expected, the acceleration length and energy increase drastically as βg approached unity. These simple scaling laws can be very instrumental in the design of better-performing plasma wakefield accelerators. 相似文献
904.
905.
Indothiazinone is a natural 3-acylindole alkaloid, isolated from a culture of myxobacterial strain. It was found to possess antibacterial activity against yeast and filamentous fungi. Indothiazinone is also structurally related with a mammalian endogenous aryl hydrocarbon receptor ligand, (2-(1′H-indole-3′-carbonyl)thiazol-4-carboxylic acid methyl ester (ITE). In this article, the synthesis of indothiazinone has been disclosed for the first time. Key feature includes direct and selective 3-acylation of indole in the presence of Lewis acid. In addition, an efficient preparation of N-substituted indothiazinone derivatives has been demonstrated. 相似文献
906.
Tao Wang Jiansheng Chen Yi Xu Lucheng Zhan Dewen Huang 《Journal of Radioanalytical and Nuclear Chemistry》2017,312(3):615-629
Daihai Lake has faced severe shrinkage in recent years due to over-exploitation. Stable isotopes (D and 18O) and hydrochemistry are employed to investigate the source of lake water to better understand its recharge dynamics. Results show that, in additional to local rainfall, groundwater is also an important water supply to the lake and accounts for a greater proportion. The groundwater is not recharged by local rainfall, but originates from other sources with significantly depleted isotope values. Combined with springs and artesian wells in the basin, it is consistent with the recent discover of external groundwater recharging in Northern China. 相似文献
907.
908.
Chang Ling Chang Shuquan Han Wei Li Zheng Zhang Zheng Dai Yaodong Zhang Haiqian 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(1):289-299
Journal of Radioanalytical and Nuclear Chemistry - The present paper, for the first time, reports the application of Ba2TiSi2O8 (BTS) for management of trivalent actinides present in radioactive... 相似文献
909.
910.
Jun‐Yi Chen Zi‐Long Xiang Feng Yu Bert F. Sels Yu Fu Ting Sun Mario Smet Wim Dehaen 《Journal of polymer science. Part A, Polymer chemistry》2014,52(18):2596-2603
A series of hyperbranched polyacenaphthenequinones has been prepared by superelectrophilic aromatic substitution of (substituted) acenaphthenequinone and 1,3,5‐tris‐(4‐phenoxybenzoyl)benzene via a facile A2 + B3 approach. Because of the strongly increased reactivity of the second A functionality, gelation was efficiently avoided during the polymerization. The structure of the resulting polymer was characterized by NMR spectroscopy and gel permeation chromatography. Further modification of the hyperbranched polyacenaphthenequinone was explored both on the acenaphthenequinone and aromatic moieties. Moreover, the polymer modified through sulfonation was investigated as a water‐soluble acid catalyst for the degradation of biomass resources. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2596‐2603 相似文献