Results 201 to 210 of about 183,857 (232)

Nonlocality in the Two-Dimensional Plasmon Dispersion

Physical Review Letters, 1985
Two-dimensional plasmons have been investigated in AlGaAs-GaAs heterostructures with transmission spectroscopy. In a magnetic field $B$, we observe an interaction of the plasmon excitation with harmonics of the cyclotron-resonance frequency ${\ensuremath{\omega}}_{c}=\frac{\mathrm{eB}}{m}$, which arises from nonlocal effects on the two-dimensional ...
, Batke, , Heitmann, , Kotthaus, , Ploog
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Laboratory observation of nonlocal dispersion

Transport in Porous Media, 1996
This work presents the results of a one-dimensional experimental investigation of contaminant transport in heterogeneous porous media. The usual transport equations fail to adequately predict dispersion in such systems, and new theories to account for the distinctions have not yet been examined experimentally.
StevenP.K. Sternberg, JohnH. Cushman, RobertA. Greenkorn   +2 more
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Nonlocal cancellation of dispersion

Optical Society of America Annual Meeting, 1991
Two classical, coincident light pulses propagating through two different dispersive media will become broadened and their degree of coincidence will be reduced. The width of the coincidence curve can be shown to be proportional to ( β 1 2 + β 2 2 ) x
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Positive eigenfunctions for nonlocal dispersal problems

Applied Mathematics Letters, 2020
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Nonlocal description of turbulent dispersion

Chemical Engineering Science, 1989
Abstract Although it is common engineering practice to model turbulent mass transport by assuming the turbulent mass flux as proportional to the local mean concentration gradient, it is well known that the applicability of this assumption is very limited, especially when the length scales and time scales of the transport process are not much smaller ...
Georgopoulos, P. G., Seinfeld, J. H.
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NMR Measurement of Nonlocal Dispersion in Complex Flows

Physical Review Letters, 2007
The flow and diffusion driven separation of initially adjacent liquid molecules is known as dispersion. The primary physical quantity describing this process, the nonlocal dispersion tensor, provides insight regarding both the spatial and temporal correlations of molecular velocity fluctuations in complex flows.
M W, Hunter, P T, Callaghan
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A dispersion series for nonlocal potentials

Journal of Mathematical Physics, 1975
For a class of short−range nonlocal potentials, and for the energy variable E in a certain part of the complex plane, we obtain a generalized subtracted dispersion relation which relates the forward scattering amplitude to contributions from negative energy pole terms, a usual dispersion integral along the positive real axis of the complex energy plane,
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Macroscale Nonlocal Dispersion

1997
In the previous chapter, we employed hybrid mixture theory to “upscale” classical continuum equations to various higher scales. To do so we required a discrete scale separation between the “pore scale” and one or more higher scales. In this chapter we make no such assumptions on scale separation.
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Prediction of negative dispersion by a nonlocal poroelastic theory

The Journal of the Acoustical Society of America, 2008
The objective of this work is to show that the negative dispersion of ultrasonic waves propagating in cancellous bone can be explained by a nonlocal version of Biot’s theory of poroelasticity. The nonlocal poroelastic formulation is presented in this work and the exact solutions for one- and two-dimensional systems are obtained by the method of Fourier
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Spatial Invasion of a Birth Pulse Population with Nonlocal Dispersal

SIAM Journal on Applied Mathematics, 2019
Summary: We propose an impulsive integro-differential model to describe the dynamics of an invading species with a pulsive reproduction stage and a nonlocal dispersal stage. We first establish a threshold-type result on the global dynamics of the system in a bounded domain, and present an application to insect pests outbreak in terms of the critical ...
Ruiwen Wu, Xiao-Qiang Zhao
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