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Journal of Structural Chemistry - In the interaction of methyl 1-bromocyclopentanecarboxylate with zinc and 1-phenylpropan-1,2-dione,... 相似文献
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Joseelyne G. Hernández‐Lima Jose E. Barquera‐Lozada Gabriel Cuevas Fernando Cortés‐Guzmán 《Journal of computational chemistry》2015,36(21):1573-1578
The normal and reverse Perlin effect is usually explained by the redistribution of electron density produced by hyperconjugative mechanisms, which increases the electron population within axial or equatorial proton in normal or reverse effect, respectively. Here an alternative explanation for the Perlin effect is presented on the basis of the topology of the induced current density, which directly determines the nuclear magnetic shielding. Current densities around the C? H bond critical point and intra‐atomic and interatomic contributions to the magnetic shielding explain the observed Perlin effect. The balance between intra‐atomic and interatomic contributions determines the difference in the total atomic shielding. Normal Perlin effect is dominated by intra‐atomic part, whereas reverse effect is dominated by interatomic contribution. © 2015 Wiley Periodicals, Inc. 相似文献
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Inside Back Cover: On the Resolution Limit of Femtosecond Stimulated Raman Spectroscopy: Modelling Fifth‐Order Signals with Overlapping Pulses (ChemPhysChem 16/2015) 下载免费PDF全文
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M.M. Elseweidy N.N. Younis S.E. Elswefy F.R. Abdallah S.I. El-Dahmy G. Elnagar 《Natural product research》2015,29(10):961-965
The anti-atherogenic potentials of total ginger (Zingiber officinale) extract (TGE) or curcuminoids extracted from turmeric (Curcuma longa), members of family Zingiberaceae, were compared in hypercholesterolaemia. Rabbits were fed either normal or atherogenic diet. The rabbits on atherogenic diet received treatments with TGE or curcumenoids and placebo concurrently for 6 weeks (n = 6). The anti-atherogenic effects of curcuminoids and ginger are mediated via multiple mechanisms. This effect was correlated with their ability to lower cholesteryl ester transfer protein activity. Ginger extract exerted preferential effects on plasma lipids, reverse cholesterol transport, cholesterol synthesis and inflammatory status. Curcuminoids, however, showed superior antioxidant activity. 相似文献
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Iron(III)‐Selective Chelation‐Enhanced Fluorescence Sensing for In Vivo Imaging Applications 下载免费PDF全文
Lin E. Guo Xin Yi Liu Huan Wang Qiu Ling Chen Guang Ke Wang Prof. Kaijun Luo Qi Li Mi Prof. Ying Zhou Jun Feng Zhang 《化学:亚洲杂志》2015,10(9):1898-1902
A “turn‐on” pattern Fe3+‐selective fluorescent sensor was synthesized and characterized that showed high fluorescence discrimination of Fe3+ over Fe2+ and other tested ions. With a 62‐fold fluorescence enhancement towards Fe3+, the probe was employed to detect Fe3+ in vivo in HeLa cells and Caenorhabditis elegans, and it was also successfully used to elucidate Fe3+ enrichment and exchange infected by innexin3 (Inx3) in hemichannel‐closed Sf9 cells. 相似文献
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