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We prove if there exists a separately continuous action of a topologically right simple semitopological semigroupS on a topological spaceX and ifS acts topologically surjective onX then each weakly almost periodic function onX, with respect toS, is left norm continuous. 相似文献
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Encapsulation of Pd(II) into superparamagnetic nanoparticles grafted with EDTA and their catalytic activity towards reduction of nitroarenes and Suzuki–Miyaura coupling 下载免费PDF全文
A robust, safe and magnetically recoverable palladium catalyst was synthesized by anchoring Pd(II) onto ethylenediaminetetraacetic acid‐coated Fe3O4 (Fe3O4@EDTA) magnetic nanoparticles. The Fe3O4 magnetic nanoparticle‐supported Pd(II)–EDTA complex catalyst thus obtained was characterized using scanning and transmission electron microscopies, thermogravimetric analysis, vibrating sample magnetometry, X‐ray diffraction, and inductively coupled plasma atomic emission and Fourier transform infrared spectroscopies. Fe3O4@EDTA–Pd(II) was screened for the Suzuki reaction and reduction of nitro compounds in water. The Pd content of the catalyst was measured to be 0.28 mmol Pd g?1. In addition, the Fe3O4@EDTA–Pd catalyst can be easily separated and recovered with an external permanent magnet. The anchored solid catalyst can be recycled efficiently and reused five times with only a very slight loss of catalytic activity. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Kobra?Hasanirokh Jafar?Azizi Arash?PhirouzniaEmail author Hakimeh?Mohammadpour 《The European Physical Journal B - Condensed Matter and Complex Systems》2014,87(4):95
In the current work, based on a semiclassical Boltzmann approach, we have investigatedthe influence of the Rashba spin-orbit coupling on spin-current of a single layer gappedgraphene. It was shown that the Rashba coupling plays a considerable role in thegeneration of the spin-current of vertical spins in mono-layer graphene. The behavior ofthe spin-current is determined by the density of impurities. It was also shown that thespin-current of the system could increase by increasing the Rashba coupling strength andband-gap of the graphene and the sign of the spin-current could be controlled by thedirection of the current-driving electric field. 相似文献
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Bahram Mokhtari Kobra Pourabdollah 《Journal of inclusion phenomena and macrocyclic chemistry》2013,76(3-4):385-390
Four nano-baskets of calixarene including cone 25,27-di(carboxymethoxy)calix[4]arene-crown-5, 1,3-alternate 25,27-di[carboxymethoxy]-calix[4]arene-crown-5, cone 25,27-bis[carboxymethoxy]calix[4]arene-crown-6 and 1,3-alternate 25,27-di[carboxymethoxy]-calix[4]arene-crown-6 were synthesized and their binding abilities towards alkali and alkaline earth metals as well as some lanthanides were studied using differential pulse voltammetry. The novelty of this study was investigation of those macrocyclic complexes by voltammetric behaviors of two acidic moieties in each scaffold during complexation of crown ether ring. Their voltammetric behaviors were closely related to the complex formation by entrapment of cation into crown ether cavity and ion–dipole interaction between cation and acidic moieties in calixcrowns. The results revealed the selective changes in voltammetric behavior of synthesized scaffolds toward the cations. Moreover, the position of crown ether in 1,3-alternate instead of cone enhanced the domain of binding ability to more cations. Furthermore, it was shown that those carboxylic acid moieties, which were far from the crown ether ring in the 1,3-alternate, did not affected by encapsulated cations in the coordination space of crown ether and showed no voltammetric behavior. 相似文献
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Bahram Mokhtari Kobra Pourabdollah 《Journal of inclusion phenomena and macrocyclic chemistry》2013,77(1-4):195-203
A novel approach for inclusion extraction and fingerprinting of metabolite was introduced base upon the emulsion liquid membrane-nuclear magnetic resonance (ELM-NMR) technique. The objective of this method is optimizing the fingerprints, minimizing the metabolic variation from analysis, increasing the likelihood differences, and obtaining the maximum extraction yield. Low molecular weight metabolites in rat serum were recovered by ELMs using three nano-baskets of calix[4]crowns-3 as emulsifier and carrier. The yields of ELMs were optimized by the method of once at a time. According to the NMR data, the maximum metabolic variation was achieved using scaffold 4 (4 wt%), n-decane membrane, stirring rate of 300 rpm, treat and phase ratios of 0.3 and 0.8, respectively. According to the NMR data, the results revealed that calixcrowns 6 and 9 tend to extract non-specific macromolecules and the repeatability of fingerprints for 4-mediated ELM was more than two others. The yield of extractions was obtained to be higher for n-decane and lower for carbon tetrachloride. Using different membrane types, the fingerprints by chlorinated liquid membranes were more repeatable than toluene or n-decane. 相似文献
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Mozhgan Aghajanzadeh Mostafa Zamani Kobra Rostamizadeh Ali Sharafi 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(7):559-571
AbstractMiktoarm star copolymers are relatively considered to be a new and unique class of macromolecules, and are a new topical area due to the unique properties by varying their polymer arms. This macromolecules with the AmBn architecture, have m arms of polymer A and n arms of polymer B connected at one central junction point. Over the past decade, miktoarms have been used in biomedical applications such as drug delivery, gene delivery, tissue engineering, diagnosis, and antibacterial/antifouling biomaterials. The intensified interest in miktoarms is attributed to their unique topological structures and attractive physical/chemical properties, including low critical micelle concentration (CMC) in solutions, encapsulation capability, internal and peripheral functionality, and enhanced stimuli-responsiveness. This review outlines the advances in the use of miktoarms in drug delivery for their good performance in biocompatibility, biodegradability and sustained, controlled and targeted drug delivery during the past decade and some unique self-assembly behaviors of miktoarm star copolymers have been reported. 相似文献
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Hamid Reza Shaterian Nafiseh Fahimi Kobra Azizi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1604-1611
Abstract An eco-friendly and mild protocol for trimethylsilyl protection of alcohols over phosphorus pentoxide supported on silica gel using hexamethyldisilazane has been described. Solvent-free and ambient reaction conditions, easy workup, short reaction times, excellent yields, and reusability of the catalyst are the noticeable features of this methodology. GRAPHICAL ABSTRACT 相似文献
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Mohammad M. Khodaei Parvin Ghanbary Iraj Mohammadpoor‐Baltork Hamid R. Memarian Ahmad R. Khosropour Kobra Nikoofar 《Journal of heterocyclic chemistry》2008,45(2):377-381
A new, facile, efficient, “green” and chemoselective procedure for the synthesis of indole derivatives has been developed with pulverization‐activation method catalyzed by Bi(NO3)3·5H2O (PAMC‐ Bi(NO3)3·5H2O) through grinding of indoles with aldehydes or Michael acceptors in the presence of catalytic amounts of Bi(NO3)3·5H2O under solvent‐free conditions. 相似文献
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Kaveh Khosravi Shirin Naserifar Boshra Mahmoudi Kobra Khalaji 《Phosphorus, sulfur, and silicon and the related elements》2017,192(3):316-321
A catalyst free and chemoselective oxidation of sulfides to sulfoxides or sulfones was developed using 1,1,2,2-tetrahydroperoxy-1,2-diphenylethane as a new oxidant. This scope has shown the achievement of various sulfoxides and sulfones which were obtained selectively in high yields at room temperature. 相似文献