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161.
162.
MR Eskildsen AB Abrahamsen PL Gammel DJ Bishop NH Andersen K Mortensen PC Canfield 《Pramana》2002,58(5-6):903-905
We compare the results of small angle neutron scattering on the flux line lattice (FLL) obtained in the borocarbide superconductor
LuNi2B2C with the applied field along the c- and a-axes. For H‖c the temperature dependence of the FLL structural phase transition from square to hexagonal symmetry was investigated. Above
10 K the transition onset field. H
2(T), rises sharply, bending away from H
c2(T) in contradiction to theoretical predictions of the two merging. For H‖a a first order FLL reorientation transition is observed at H
tr=3–3.5 kOe. Below H
tr the FLL nearest neighbor direction is parallel to the b-axis, and above H
tr to the c-axis. This transition cannot be explained using nonlocal corrections to the London model. 相似文献
163.
164.
165.
Mee Hyea Yang 《Journal of Applied Mathematics and Computing》1996,3(2):117-127
Complementation theory in Krein spaces can be extended for any self-adjoint transformation. There is a close relation between Julia operators and linear systems. The theory of Julia operators can be used to construct distinct Krein spaces which are the state spaces of extended canonical linear systems with given transfer function. 相似文献
166.
Homogeneous isotropic turbulence consists of coherent filamentary vortex structures superimposed to a more incoherent background. The question which we address is the effect of these structures on the dynamics of small, neutrally buoyant solid particles. Rather than generating the turbulence by direct numerical simulation (DNS) of the Navier-Stokes equations, we use a model of turbulence based entirely on viscous vortex filaments which interact via inertial forces and reconnect with each other. Using this model, we show that solid particles can become trapped around vortex filaments, something difficult to achieve with DNS. Unlike most studies, we have not neglected inviscid inertial effects. By comparing the Stokes, local, and convective components of the particle's acceleration, we also show that the convective part clearly identifies the trapping. 相似文献
167.
Clinch K Evans GB Furneaux RH Lenz DH Mason JM Mee SP Tyler PC Wilcox SJ 《Organic & biomolecular chemistry》2007,5(17):2800-2802
The title compound (+)-, required for production of transition state analogue inhibitors of enzymes involved in T-cell-dependent disorders, was synthesized in five steps. A 1,3-dipolar cycloaddition of the nitrone formed from formaldehyde and N-benzylhydroxylamine to diethyl maleate gave the racemic cis-isoxazolidine (+/-)-. Reduction of the N-O bond of this compound gave pyrrolidone (+/-)- in excellent yield. A very efficient enzymic resolution of this racemic product led to the title enantiomer (+)-. This route employs only one chromatographic purification. 相似文献
168.
Niranjan Sahoo Kiran Suryavamshi K. P. J. Reddy David J. Mee 《Experiments in fluids》2005,38(5):606-614
Two force balance techniques for use in hypersonic impulse facilities are compared by measuring the drag force on a 30° semi-apex-angle blunt cone model in a hypersonic shock tunnel at a free stream Mach number of 5.75. An accelerometer-based balance and a stress-wave force balance were tested simultaneously on the same model to measure the drag force. It was found that drag force measurements could be made using both techniques in a flow with a 450-s test period. The measured drag forces compared well with the theoretical values estimated using Newtonian theory. 相似文献
169.
In this paper, experiments to detect turbulent spots in the transitional boundary layers, formed on a flat plate in a free-piston
shock tunnel flow, are reported. Experiments indicate that thin-film heat-transfer gauges are suitable for identifying turbulent-spot
activity and can be used to identify parameters such as the convection rate of spots and the intermittency of turbulence. 相似文献
170.
A Linker‐Mediated Self‐Assembly Method to Couple Isocharged Nanostructures: Layered Double Hydroxide–CdS Nanohybrids with High Activity for Visible‐Light‐Induced H2 Generation
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Jang Mee Lee Jayavant L. Gunjakar Yeilin Ham In Young Kim Prof. Kazunari Domen Prof. Seong‐Ju Hwang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(51):17004-17010
The electrostatically derived self‐assembly of cationic Zn‐Cr‐layered double hydroxide (LDH) nanosheets and cationic CdS quantum dots (QDs) with anionic linkers leads to the formation of strongly coupled Zn‐Cr‐LDH–CdS nanohybrids. The hybridization with Zn‐Cr‐LDH leads to significant enhancement of the photocatalytic activity of CdS for visible‐light‐induced H2 generation, a property that is attributed to the depression of electron–hole recombination. In comparison with a direct hybridization method between oppositely charged species, this linker‐mediated method provides greater flexibility in controlling the chemical composition and electronic coupling of the nanohybrids. The present hybridization strategy provides a useful method not only to couple two kinds of isocharged nanostructured materials, but also to explore efficient hybrid‐type photocatalysts. 相似文献