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排序方式: 共有721条查询结果,搜索用时 31 毫秒
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Dr. Carmine D'Agostino Dr. Tatyana Kotionova Dr. Jonathan Mitchell Dr. Peter J. Miedziak Prof. David W. Knight Dr. Stuart H. Taylor Prof. Graham J. Hutchings Prof. Lynn F. Gladden Dr. Mick D. Mantle 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(35):11725-11732
In recent work, it was reported that changes in solvent composition, precisely the addition of water, significantly inhibits the catalytic activity of Au/TiO2 catalyst in the aerobic oxidation of 1,4‐butanediol in methanol due to changes in diffusion and adsorption properties of the reactant. In order to understand whether the inhibition mechanism of water on diol oxidation in methanol is generally valid, the solvent effect on the aerobic catalytic oxidation of 1,3‐propanediol and its two methyl‐substituted homologues, 2‐methyl‐1,3‐propanediol and 2,2‐dimethyl‐1,3‐propanediol, over a Au/TiO2 catalyst has been studied here using conventional catalytic reaction monitoring in combination with pulsed‐field gradient nuclear magnetic resonance (PFG‐NMR) diffusion and NMR relaxation time measurements. Diol conversion is significantly lower when water is present in the initial diol/methanol mixture. A reactivity trend within the group of diols was also observed. Combined NMR diffusion and relaxation time measurements suggest that molecular diffusion and, in particular, the relative strength of diol adsorption, are important factors in determining the conversion. These results highlight NMR diffusion and relaxation techniques as novel, non‐invasive characterisation tools for catalytic materials, which complement conventional reaction data. 相似文献
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Victor V. Dotsenko Arif I. Ismiev Anastasiya N. Khrustaleva Konstantin A. Frolov Sergey G. Krivokolysko Elena A. Chigorina Aleksey P. Snizhko Vladimir M. Gromenko Ivan S. Bushmarinov Rizvan K. Askerov Tatyana M. Pekhtereva Sergey Yu. Suykov Elena S. Papayanina Aleksandr V. Mazepa Abel M. Magerramov 《Chemistry of Heterocyclic Compounds》2016,52(7):473-483
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Galina A. Gazieva Yurii B. Vikharev Lada V. Anikina Tatyana B. Karpova Angelina N. Kravchenko Evgenii A. Permyakov Igor V. Svitanko 《Mendeleev Communications》2013,23(4):202-203
Target synthesis of substituted thioglycolurils possessing sedative activity predicted by preliminary 3D-QSAR simulation of bioactive structures has been carried out. 相似文献
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Martin I. Kabachnik Tatyana A. Mastryukova Andrei B. Ou-Rwpin Mikhail I. Kadyko Pavel V. Petrovskii Erlen I. Fedin 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract The enantiomeric ratio in non-racemic mixtures of 2-anilino-2-oxo-1,3,2-oxazaphospho-rinane (I) and 3-(α-rnethylbenzyl)-(I)1 enantiomers was determined by measurement of the integral intensity ratio of two 31P-NMR signals, assigned to enantiomers and differentiated due to the effect of statistically controlled associate-diastereoisomerim (scada), 2 when association occurs under conditions of fast exchange. 相似文献
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Shestakova Tatyana S. Deev Sergey L. Khalymbadzha Igor А. Rusinov Vladimir L. Paramonov Alexander S. Arseniev Alexander S. Shenkarev Zakhar O. Charushin Valery N. Chupakhin Oleg N. 《Chemistry of Heterocyclic Compounds》2021,57(4):479-482
Chemistry of Heterocyclic Compounds - Isotope-labeled antiviral drug Triazavirin containing 2H, 13C, and 15N atoms in its structure has been synthesized. 13C2H3I and KS13CN served as donors of 13C... 相似文献
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Andrei B. Ouryupin Pavel V. Petrovskii Ivan A. Rakhov Tatyana A. Mastryukova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract The reaction of trimethylsilylisothiocyanate with phosphorus acids chlorides was demonstrated to be reversible. 相似文献
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