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971.
B. Lautrup R. Appali A. D. Jackson T. Heimburg 《The European physical journal. E, Soft matter》2011,34(6):57
We examine the stability of a class of solitons, obtained from a generalization of the Boussinesq equation, which have been
proposed to be relevant for pulse propagation in biomembranes and nerves. These solitons are found to be stable with respect
to small-amplitude fluctuations. They emerge naturally from non-solitonic initial excitations and are robust in the presence
of dissipation. Solitary waves pass through each other with only minor dissipation when their amplitude is small. Large-amplitude
solitons fall apart into several pulses and small-amplitude noise upon collision when the maximum density of the membrane
is limited by the density of the solid phase membrane. 相似文献
972.
The aim of this research on the laser material yttrium lithium fluoride (YLiF4) is to provide the first study of its surface structure, morphology and the properties of rare-earth doped surfaces. The study utilises the METADISE computer code to model the surfaces using interatomic potentials. Equilibrium and growth morphologies are predicted and a detailed profile of segregation of rare-earth dopants to the three dominating surfaces is given. The (001), (011) and (112) surfaces dominate the morphology. Rare-earth dopants La to Sm show segregation to these surfaces, with the (112) surface being of particular interest. As this work demonstrates, it is likely to have dopants clustered towards it. 相似文献
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The generation of constitutive detonation performance model components for high explosives (HEs) invariably involves reference to experiment, as reliable first-principles determinations of these models are beyond our current capability. Whatever its form or complexity, the detonation performance model must be able to accurately capture the detonation wave timing and the energy release that it triggers upon arrival. Specifically, the HE products equation-of-state (EOS), which largely determines the detonating HE’s ability to do useful work on its surroundings, is typically inferred from cylinder expansion tests where metal-confined HE cylinders are detonated and the ensuing outer confiner wall-expansion trajectory is recorded. Expensive, iterative comparisons to multimaterial hydrodynamic (or “hydrocode”) simulations of these experiments are then used to constrain the parameters of the chosen EOS form. Here, we report on new detonation performance experiments produced for the highly-ideal, plastic-bonded explosive and CL-20-based LX-19 which are used to produce a new sub-scale detonation performance model for the explosive. This includes new products EOS and a new Detonation Shock Dynamics front propagation law. We also confirm the capability of two new, non-hydrocode-based products EOS generation techniques to accelerate the HE model parameterization process. This latter development is particularly significant for detonation performance modeling of new HE formulations. 相似文献
975.
Niu Yufu Jackson Samuel J. Alqahtani Naif Mostaghimi Peyman Armstrong Ryan T. 《Transport in Porous Media》2022,144(3):825-847
Transport in Porous Media - X-ray micro-computed tomography (micro-CT) has been widely leveraged to characterise the pore-scale geometry of subsurface porous rocks. Recent developments in... 相似文献
976.
Global spatial distributions of nitrogen and carbon stable isotope ratios of modern human hair
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We develop a computationally efficient optimization procedure to optimize stock and rationing levels for a model consisting of a single product with two priority–demand classes, given by mutually independent, stationary, Poisson demand processes. Each priority class has its own service levels requirements, defined by the class-specific fill rate and expected waiting-time levels. Order lead times are independent and identically distributed random variables. This is the first study in this setting to consider both waiting-time constraints along with fill rate requirements. 相似文献