4,693 research outputs found
Capillary wave dynamics on supported viscoelastic films: Single and double layers
We study the capillary wave dynamics of a single viscoelastic supported film
and of a double layer of immiscible viscoelastic supported films. Using both
simple scaling arguments and a continuum hydrodynamic theory, we investigate
the effects of viscoelasticity and interfacial slip on the relaxation dynamics
of these capillary waves. Our results account for the recent observation of a
wavelength-independent decay rate for capillary waves in a supported
polystyrene/brominated polystyrene double layer [X. Hu {\em et al.}, Phys. Rev.
E {\bf 74}, 010602 (R) (2006)].Comment: 14 pages, 9 figure
Equilibrium Bundle Size of Rodlike Polyelectrolytes with Counterion-Induced Attractive Interactions
Multivalent counterions can induce an effective attraction between
like-charged rodlike polyelectrolytes, leading to the formation of
polelectrolyte bundles. In this paper, we calculate the equilibrium bundle size
using a simple model in which the attraction between polyelectrolytes (assumed
to be pairwise additive) is treated phenomenologically. If the counterions are
point-like, they almost completely neutralize the charge of the bundle, and the
equilibrium bundle size diverges. When the counterions are large, however,
steric and short-range electrostatic interactions prevent charge neutralization
of the bundle, thus forcing the equilibrium bundle size to be finite. We also
consider the possibility that increasing the number of nearest neighbors for
each rod in the bundle frustrates the attractive interaction between the rods.
Such a frustration leads to the formation of finite size bundles as well, even
when the counterions are small.Comment: 4 pages, 2 figures; v2: typos corrected, references added, minor
changes made to conten
Illinois Career Pathways Initiative: Vision and Goals
Career pathways are sets of connected courses and programs that enable students to advance over time to better jobs and higher levels of education and training. Career pathways target high-wage jobs in important economic sectors. Learn more about the goals of the Illinois Career Pathways Initiative
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