Structural Transition from Helices to Hemihelices
Figure 3
The number of perversions observed as a function of both the prestrain and the cross-section aspect ratio, .
The data indicates that there is a transition between the formation of helixes at larger aspect ratios and hemihelices at smaller aspect ratios. The precise phase boundary cannot be determined with any precision experimentally and so is shown shaded but there is evidently only a weak dependence on the value of the pre-strain. In some cases, bistrips made the same way produce either one or the other of the two perversion numbers indicated.