. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. VISCOELAST1CITY OF SEA CUCUMBER W 273. Figure 9. Schematic of a simple polymer model for the dermis. A single mesh is drawn. Top row portrays. from left to right, the soft state, the standard state, and the stiff state. Hollow circle, intermolecular bond; rilled circle, segmental bond that deforms elastically when stretched; stippled circle, segmental bond that deforms plastically when stretched. The folded structure of the segment is drawn only for one side of a mesh. Central column is the mesh of the standard state under i
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. VISCOELAST1CITY OF SEA CUCUMBER W 273. Figure 9. Schematic of a simple polymer model for the dermis. A single mesh is drawn. Top row portrays. from left to right, the soft state, the standard state, and the stiff state. Hollow circle, intermolecular bond; rilled circle, segmental bond that deforms elastically when stretched; stippled circle, segmental bond that deforms plastically when stretched. The folded structure of the segment is drawn only for one side of a mesh. Central column is the mesh of the standard state under increasing strain from top to bottom when stretched horizontally. The mesh is free to deform (middle): the segmental bonds experience deformation after the segments become oriented parallel to the direction of stretch (bottom). In the soft state, the length of the toe region remained the same as that in the standard state. From this result we postulate that the segment length remains the same, and thus the number of inter-molecular bonds remained unchanged at the transition from standard to soft states (upper left of Fig. 9). The segmental bonds are, however, postulated to de- crease in number. Removal of segmental bonds makes the segment more flexible and stretchy, which accounts for the low stiffness of the pole region in the soft state. A fair proportion of the remaining segmental bonds show plastic deformation on stretch, producing a fairly large J index at unloading and a large dissipation ratio in the soft state. In the soft state, segmental bonds break when the strain ex- ceeds some limit. This endows the model with strain-soft- ening behavior. The loss of segmental bonds that had held the folded structure of the chain results in elongation of the segment. This explains the longer toe region in samples that experienced strain-induced softening. The breakage of bonds also accounts for the decrease in the maximum stress. This meshwork model simulates well the mechanical beh
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
