论文标题
淀粉样蛋白纤维液晶触发器中流动诱导的订单级过渡
Flow-induced order-order transitions in amyloid fibril liquid crystalline tactoids
论文作者
论文摘要
在科学的多个分支中,了解和控制nematic和胆汁灰质液晶中的主管现场配置,形状和方向至关重要。液晶液滴液滴,也称为触机,它们是通过相图的双相区域内的成核和生长自发形成的,在各向同性和夜间阶段共存,挑战我们当前对固定液体的理解,这是由于各向异性表面边界的影响,在各种表面界面的影响下,小小的际交往量不足地进行了研究。在这里,我们表明,不同类别的淀粉样蛋白原纤维孕和胆汁固醇的触觉通过流动诱导的形状变形经历了平衡的订单阶阶段。触觉在延伸流下对齐,并将极端变形变成高度伸长的形状,从而使胆固醇的螺距可以作为触觉纵横比的反功率定律降低。能量函数理论和实验测量合并以合理化临界伸长率,在该比例之上,触觉的导演场构型从双极性和单轴胆汁灰质物转变为同质性,并就这些过渡的热力学性质进行了争论。我们的发现提出了设计自组装液晶材料的新机会,在这些材料中,可以通过非平衡相变来调整结构和动力学特性。
Understanding and controlling the director field configuration, shape, and orientation in nematic and cholesteric liquid crystals is of fundamental importance in several branches of science. Liquid crystalline droplets, also known as tactoids, which spontaneously form by nucleation and growth within the biphasic region of the phase diagram where isotropic and nematic phases coexist, challenge our current understanding of liquid crystals under confinement, due to the influence of anisotropic surface boundaries at vanishingly small interfacial tension and are mostly studied under quiescent, quasi-equilibrium conditions. Here, we show that different classes of amyloid fibril nematic and cholesteric tactoids undergo out-of-equilibrium order-order transitions by flow-induced deformations of their shape. The tactoids align under extensional flow and undergo extreme deformation into highly elongated oblate shapes, allowing the cholesteric pitch to decrease as an inverse power law of the tactoids aspect ratio. Energy functional theory and experimental measurements are combined to rationalize the critical elongation ratio above which the director-field configuration of tactoids transforms from bipolar and uniaxial cholesteric to homogenous and to debate on the thermodynamic nature of these transitions. Our findings suggest new opportunities in designing self-assembled liquid crystalline materials where structural and dynamical properties may be tuned by non-equilibrium phase transitions.