Emile Olivier, Le Floch Albert, Vollrath Fritz
Laboratoire de Physique des Lasers, UMR CNRS 6627, Université de Rennes 1, 35042 Rennes, France.
Nature. 2006 Mar 30;440(7084):621. doi: 10.1038/440621a.
The ductility and strength of spider draglines means that they outperform the best synthetic fibres, but surprisingly little is known about the torsional properties of this remarkable filament. Unlike a mountain climber swinging from a rope, a spider suspended from its silk thread hardly ever twists. Here we show that a spider dragline has a torsional shape 'memory' in that it can reversibly and totally recover its initial form without any external stimulus; its observed relaxation dynamics indicate that these biological molecules have successively different torsional constants.
蜘蛛丝的延展性和强度意味着它们优于最好的合成纤维，但令人惊讶的是，对于这种非凡细丝的扭转特性却知之甚少。与从绳索上摆动的登山者不同，悬挂在蛛丝上的蜘蛛几乎不会扭转。我们在此表明，蜘蛛丝具有扭转形状“记忆”，即它可以在没有任何外部刺激的情况下可逆且完全恢复其初始形态；观察到的松弛动力学表明，这些生物分子具有相继不同的扭转常数。
