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تسجيل مستخدم جديدRaft Instability of Biopolymer Gels
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Following recent X-ray diffraction experiments by Wong, Li, and Safinya on biopolymer gels, we apply Onsager excluded volume theory to a nematic mixture of rigid rods and strong ``$pi/2$ cross-linkers obtaining a long-ranged, highly anisotropic depletion attraction between the linkers. This attraction leads to breakdown of the percolation theory for this class of gels, to breakdown of Onsagers second-order virial method, and to formation of heterogeneities in the form of raft-like ribbons.
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