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81.
Journal of Solid State Electrochemistry - A hybrid nanomaterial with palladium nanoparticles (PdNps) supported on reduced graphene oxide (rGO) flakes, dispersed in an aqueous solution was...  相似文献   
82.
The “solvophobic” effect is the tendency of solute particles to cluster as the attractive interaction between solvent particles is strengthened. The potentials of mean force in the hypernetted chain approximation have been obtained for a simple fluid mixture consisting of two hard spheres immersed in a hard core/Yukawa tail solvent. The results clearly exhibit features attributable to the “solvophobic” effect.  相似文献   
83.
Chromatographia - Nucleobases, nucleosides and nucleotides can act as chemical markers and immunnostimulants. Ultra-high-performance liquid chromatography with electrospray ionization and...  相似文献   
84.
The redox activity of molecular phenazine catalysts has been previously exploited for aerobic oxidative amine homo- and cross-coupling reactions. In this contribution, we have extended the reaction scope of this novel type of organocatalyst and used them in the cross-dehydrogenative aza-Henry coupling of isoquinolines with nitromethane under aerobic conditions. Additionally, we have designed and prepared a novel porous organic polymer by cross-linking of tetrakis(4-bromophenyl)silane and dihydrophenazine through Pd-catalyzed Buchwald-Hartwig cross-coupling. This new type of heterogeneous catalyst, apart from being robust and easily reusable, also showed outstanding catalytic activities and improved selectivity compared to its molecular counterpart. A plausible reaction mechanism was proposed based on spectroscopic and kinetic measurements.  相似文献   
85.
86.
Structural Chemistry - An in silico analysis of the oxidation mechanism of allyl methyl disulfide (AMDS) by hydroxyl radical was achieved at DFT level using B3LYP, CAM-B3LYP, M06-2X, and BMK...  相似文献   
87.
The reactions of elemental phosphorus, arsenic and antimony with sodium metal in liquid ammonia form “M?1“ species that react with haloarenes under irradiation to form symmetrical triaryl derivatives of these metals by the SRN1 mechanism in fair to good yields. Further reaction with sodium metal gives a derivative nucleophile (diarylphosphide and diarylarsenide ions) that reacts with another haloarene under irradiation to form unsymmetrical phosphines and arsines.  相似文献   
88.
The anodic processes which occur at the mercury electrode in 2-mercaptoethanol solutions are studied by various polarographic techniques (d.c., a.c. and differential pulse), controlled-potential coulometry, cyclic voltammetry and differential capacity curves. Two steps are distinguished in the process: a one-electron charge transfer and a dismutation step leading to the formation of a mercury(II) mercaptide. The final product is isolated and analyzed. Differential-pulse polarography can be used to determine ?10?4 M 2-mercaptoethanol with a limit of M.  相似文献   
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90.
Simple turbulent diffusive models are proposed as conceptual tools for exploring scenarios involving mixing of stratified flows. Applications include the dynamics of the ocean's top mixed layer, shear instability, breaking internal waves, and turbulent stirring of sharp interfaces. A novel measure of mixing is developed, based on arguments from statistical physics. It is shown that, under turbulent diffusion, this measure grows, and that there are strong indications that, under stirring, flows tend to settle down at a maximum of this measure, subject to global dynamical constraints. © 2004 Wiley Periodicals, Inc.  相似文献   
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