Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Mixtures of Charged Colloid and Neutral Polymer: Influence of
  Electrostatic Interactions on Demixing and Interfacial Tension   The equilibrium phase behavior of a binary mixture of charged colloids and
neutral, non-adsorbing polymers is studied within free-volume theory. A model
mixture of charged hard-sphere macroions and ideal, coarse-grained,
effective-sphere polymers is mapped first onto a binary hard-sphere mixture
with non-additive diameters and then onto an effective Asakura-Oosawa model [S.
Asakura and F. Oosawa, J. Chem. Phys. 22, 1255 (1954)]. The effective model is
defined by a single dimensionless parameter -- the ratio of the polymer
diameter to the effective colloid diameter. For high salt-to-counterion
concentration ratios, a free-volume approximation for the free energy is used
to compute the fluid phase diagram, which describes demixing into colloid-rich
(liquid) and colloid-poor (vapor) phases. Increasing the range of electrostatic
interactions shifts the demixing binodal toward higher polymer concentration,
stabilizing the mixture. The enhanced stability is attributed to a weakening of
polymer depletion-induced attraction between electrostatically repelling
macroions. Comparison with predictions of density-functional theory reveals a
corresponding increase in the liquid-vapor interfacial tension. The predicted
trends in phase stability are consistent with observed behavior of
protein-polysaccharide mixtures in food colloids.

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The categories of this paper are: physics
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The categories of this paper are: q-alg
8
The categories of this paper are: hep-ex
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The categories of this paper are: q-fin
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The categories of this paper are: solv-int
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The categories of this paper are: econ
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The categories of this paper are: math-ph
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: cmp-lg
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The categories of this paper are: comp-gas
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The categories of this paper are: nlin
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The categories of this paper are: quant-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: stat