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71.
72.
Amber L. Broadbent Jim M. Mullin Sarah L. Codd Jack D. Dockery Joseph D. Seymour 《Applied magnetic resonance》2012,42(1):137-152
Magnetic resonance microscopy and Ansys Fluent? computational fluid dynamics simulation have been used to classify Taylor vortex flows (TVF) for several single fluid and
axially stratified two-fluid systems in a vertically oriented Taylor–Couette device. A Rheo-NMR (nuclear magnetic resonance)
Couette system (Magritek Ltd, New Zealand) with a 1.05-mm gap was used to evaluate the transition from Couette flow to TVF
in 1.65 cSt silicone oil, 1 cSt deionized water, and 0.65 cSt silicone oil. The rotation rate at which instability onset occurred
agreed between experiment and simulation, as did the critical wavelength. Velocities were mapped for axially stratified two-fluid
systems. The vortex containing the two-fluid interface was found to form with a significantly longer wavelength than that
observed in the pure fluids. For experiments and simulations in the TVF regime, a region with no secondary flows was found
at the interface, indicating interface stabilization by surface tension forces. 相似文献
73.
Scott A. Mullin Alexander A. Teran Rodger Yuan Nitash P. Balsara 《Journal of Polymer Science.Polymer Physics》2013,51(12):927-934
We have studied the effect of thermal history on ionic conductivity of block copolymer electrolytes. Previous work on block copolymer electrolytes composed of polystyrene‐b‐poly(ethylene oxide) (SEO) and lithium bis(trifluoromethanesulfone) imide (LiTFSI) salt was restricted to lamellar morphologies. This study addresses both cylindrical and lamellar morphologies. The conductivity of low molecular weight samples decreases after they are annealed. In contrast, the conductivity of high molecular weight samples is generally unaffected by annealing. These results are explained in the context of connectivity and composition of the conducting phase. © 2013 Wiley Periodicals, Inc. J. Polym. Sci. Part B: Polym. Phys. 2013 , 51, 927–934 相似文献
74.
Successive oxidation of transition metal(II) aqua complexes (M(II)OH(2) to M(III)OH) is a domain in which proton-coupled electron transfer reactions are extremely common. The mechanism of these PCET reactions-concerted or stepwise-is an important issue in the understanding and design of natural or artificial systems catalyzing the formation of dioxygen by four-electron oxidation of water. Concerted proton-coupled electron transfer from an aqua metal(II) to a hydroxo metal(III) complex requires the close proximity of a proton-accepting group with a pK value between those of the aqua complexes. Otherwise, stepwise electron-proton or proton-electron pathways involving high-energy intermediates are followed. Concerted proton-electron pathways involving water as proton-acceptor or proton-donor group are inefficient. Cyclic voltammetry of the title complex in buffered aqueous solution and re-examination of previous results for the same complex attached to an electrode surface are used to establish these conclusions, which provide a starting point on the route to higher degrees of oxidation, such as those involved in the catalysis of water oxidation. 相似文献
75.
A. Yeremin O. Malyshev A. Popeko A. Lopez-Martens K. Hauschild O. Dorvaux S. Saro D. Pantelica S. Mullin 《Pramana》2010,75(1):3-12
Detailed spectroscopic information of excited nuclear states in deformed transfermium nuclei is scarce. Most of the information
available today has been obtained from investigations of fine-structure α-decay. Although α decay gives access to hindrance factors and lifetimes which are strongly correlated to shell/subshell closures and the presence
of isomers, only the combined use of γ and conversion electron spectroscopy allows the precise determination of excitation energy, spin and parity of nuclear levels. 相似文献
76.
We introduce the notion of a symmetric graph design which is a common generalization of symmetric BIBDs and of orthogonal
double covers.
Revised: January 21, 1999 相似文献
77.
78.
We analyse different error propagation mechanisms for conservativeand nonconservative time-integrators of nonlinear Schrödingerequations. We use a geometric approach based on interpretingwaves as relative equilibria. 相似文献
79.
Alan C. H. Ling Xiaojun Zhu Charles J. Colbourn Ronald C. Mullin 《Designs, Codes and Cryptography》1997,10(2):203-222
This paper deals with existence for pairwise balanced designs with block sizes 5,6 and 7, block sizes 6,7 and 8 and block sizes 7,8 and 9 and some consequences of these results. 相似文献
80.
Alexander A. Teran Maureen H. Tang Scott A. Mullin Nitash P. Balsara 《Solid State Ionics》2011,203(1):18-21
The ionic conductivity, σ, of mixtures of poly(ethylene oxide) (PEO) and lithium bis(trifluoromethanesulfone)imide (LiTFSI) was measured as a function of molecular weight of the PEO chains, M, over the range 0.2-5000 kg/mol. Our data are consistent with an expression σ = σ0 + K/M proposed by Shi and Vincent [Solid State Ionics 60 (1993)] where σ0 and K are exponential and linear functions of inverse temperature respectively. Explicit expressions for σ0 and K are provided. 相似文献