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1.
Synthesis of Small‐Sized,Porous, and Low‐Toxic Magnetite Nanoparticles by Thin POSS Silica Coating 下载免费PDF全文
Dr. Swee Kuan Yen D. Prathyusha Varma Wei Mei Guo Dr. Vincent H. B. Ho Dr. Vimalan Vijayaragavan Dr. Parasuraman Padmanabhan Prof. Kishore Bhakoo Prof. Subramanian Tamil Selvan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(10):3914-3918
In this communication, we report the synthesis of small‐sized (<10 nm), water‐soluble, magnetic nanoparticles (MNPs) coated with polyhedral oligomeric silsesquioxanes (POSS), which contain either polyethylene glycol (PEG) or octa(tetramethylammonium) (OctaTMA) as functional groups. The POSS‐coated MNPs exhibit superparamagnetic behavior with saturation magnetic moments (51–53 emu g?1) comparable to silica‐coated MNPs. They also provide good colloidal stability at different pH and salt concentrations, and low cytotoxicity to MCF‐7 human breast epithelial cells. The relaxivity data and magnetic resonance (MR) phantom images demonstrate the potential application of these MNPs in bioimaging. 相似文献
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Identification of metabolites of rupestonic acid in rat urine by liquid chromatography combined with electrospray ionization quadrupole time‐of‐flight tandem mass spectrometry 下载免费PDF全文
Dongyu Gu Yi Yang Qibin Chen Madina Habasi Jiangyu Zhao Haji Akber Aisa 《Biomedical chromatography : BMC》2015,29(4):595-603
Rupestonic acid, a potential anti‐influenza agent, is an important and characteristic compound in Artemisia rupestris L., a well‐known traditional Uighur medicine for the treatment of colds. In the present study, high‐performance liquid chromatography combined with electrospray ionization quadrupole time‐of‐flight tandem mass spectrometry was used to detect and identify the metabolites in rat urine after oral administration of rupestonic acid. A total of 10 metabolites were identified or partially characterized. The structure elucidations of the metabolites were performed by comparing the changes in accurate molecular masses and fragment ions with those of the parent compound. The results showed that the main metabolites of rupestonic acid in rat urine were formed by oxidation, hydrogenation and glucuronidation. A metabolism pathway was proposed for the first time based on the characterized structures. This metabolism study can provide essential information for drug discovery, design and clinical application of rupestonic acid. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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通过分析计算,设计了一种大口径宽视场折射式红外相机光学系统。该系统设计用于超长线阵扫描红外相机的地面演示成像,它能同时对短波2μm—3μm、中波3μm—4.5μm双波段成像,且同时具有24°的大视场和150mm的宽口径,成像质量接近衍射极限。该系统在航天遥感领域应用广泛。 相似文献
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K. Dayananda R. Dhamodharan K. Vijayakumaran T. Rajamannar 《Journal of polymer science. Part A, Polymer chemistry》2004,42(21):5413-5423
A monolayer of covalently anchored, novel, binaphthyl ketone is used as a surface‐confined photochemical radical generator (PRG) for anchoring a variety of polymers to silicon surfaces. The precursor PRG is synthesized by the application of a facile and novel method for the oxidation of sterically hindered benzylic hydrocarbons to carbonyl compounds. Oxidation was carried out with a stoichiometric amount of potassium peroxydisulfate, in the presence of a catalytic amount of copper sulfate in an acetonitrile/water mixture. The PRG synthesized is characterized by 1H NMR, UV, and Fourier transform infrared (FTIR). The covalently attached monolayers are characterized by X‐ray photoelectron spectroscopy, ellipsometry, and water contact angle measurements. The method developed is applicable to the preparation of a monolayer of a variety of polymers on a wide range of substrates carrying surface hydroxyl groups. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5413–5423, 2004 相似文献
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Panagiota G. Fragouli Hermis Iatrou Nikos Hadjichristidis 《Journal of polymer science. Part A, Polymer chemistry》2004,42(3):514-519
A series of five tetrablock quarterpolymers of styrene, isoprene, dimethylsiloxane, and 2-vinylpyridine with molecular weights varying from 117 × 103 to 177 × 103 and having different compositions were synthesized. The synthesis was based on recent advances in the controlled high-vacuum anionic polymerization of hexamethylcyclotrisiloxane and on the selective linking of poly(dimethylsiloxane)lithium with the chlorosilane group of the heterofunctional linking agent chloromethylphenylethylene dimethylchlorosilane. Combined characterization results by size exclusion chromatography, membrane osmometry, and NMR spectroscopy suggested that the synthesized multiblock multicomponent polymers had a high degree of structural and compositional homogeneity. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 514–519, 2004 相似文献
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将自卫机制加入OOP成为AOP以提高CORBA中软件的强健性和防卫能力,在CORBA这个异构环境中,一个对象申请服务之后就需等待,如果应答迟迟不到则有可能永远等待下去,为避免这种现象的产生和蔓延,在客户和服务方的行为中加入超时机制(timeout mecha-nism)并采用利己或利他策略,使得对象可独立地根据当前环境和时间决定下一步骤,将这种在协作者失败的情况下仍能生存的对象称为自卫智能体,加入白卫智能体的CORBA称为CORBA~( ),由于智能体可在任何条件下生存,CORBA~( )可为用户提供可靠的服务,也就能实现CORBA~( )中软件构成的强健性。 相似文献
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Recently, molecular imaging has been rapidly developed to studyphysiological and pathological processes in vivo at the cellularand molecular levels. Among molecular imaging modalities, opticalimaging has attracted a major attention for its unique advantages.In this paper, we establish a mathematical framework for multispectralbioluminescence tomography (BLT) that allows simultaneous studiesof multiple optical reporters. We show solution existence, uniquenessand continuous dependence on data as well as the limiting behaviourswhen the regularization parameter approaches zero or when thepenalty parameter approaches infinity. Then, we propose twonumerical schemes for multispectral BLT and derive error estimatesfor the corresponding solutions. 相似文献