Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Instabilities in freely expanding sheets of associating viscoelastic
  fluids   We use the impact of drops on a small solid target as a tool to investigate
the behavior of viscoelastic fluids under extreme deformation rates. We study
two classes of transient networks: semidilute solutions of supramolecular
polymers and suspensions of spherical oil droplets reversibly linked by
polymers. The two types of samples display very similar linear viscoelastic
properties, which can be described with a Maxwell fluid model, but contrasting
nonlinear properties due to different network structure. Upon impact, weakly
viscoelastic samples exhibit a behavior qualitatively similar to that of
Newtonian fluids: A smooth and regular sheet forms, expands, and then retracts.
By contrast, for highly viscoelastic fluids, the thickness of the sheet is
found to be very irregular, leading to instabilities and eventually formation
of holes. We find that material rheological properties rule the onset of
instabilities. We first provide a simple image analysis of the expanding sheets
to determine the onset of instabilities. We then demonstrate that a Deborah
number related to the shortest relaxation time associated to the sample
structure following a high shear is the relevant parameter that controls the
heterogeneities in the thickness of the sheet, eventually leading to the
formation of holes. When the sheet tears-up, data suggest by contrast that the
opening dynamics depends also on the expansion rate of the sheet.

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The categories of this paper are: bayes-an
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The categories of this paper are: hep-ex
3
The categories of this paper are: physics
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The categories of this paper are: chem-ph
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The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
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The categories of this paper are: q-alg
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The categories of this paper are: hep-lat
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th
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The categories of this paper are: atom-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: ao-sci
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The categories of this paper are: acc-phys
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The categories of this paper are: math
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The categories of this paper are: funct-an