Stanford Advisors

2013-14 Courses

All Publications

  • Non-invasive determination of the complete elastic moduli of spider silks NATURE MATERIALS Koski, K. J., Akhenblit, P., McKiernan, K., Yarger, J. L. 2013; 12 (3): 262-267


    Spider silks possess nature's most exceptional mechanical properties, with unrivalled extensibility and high tensile strength. Unfortunately, our understanding of silks is limited because the complete elastic response has never been measured-leaving a stark lack of essential fundamental information. Using non-invasive, non-destructive Brillouin light scattering, we obtain the entire stiffness tensors (revealing negative Poisson's ratios), refractive indices, and longitudinal and transverse sound velocities for major and minor ampullate spider silks: Argiope aurantia, Latrodectus hesperus, Nephila clavipes, Peucetia viridans. These results completely quantify the linear elastic response for all possible deformation modes, information unobtainable with traditional stress-strain tests. For completeness, we apply the principles of Brillouin imaging to spatially map the elastic stiffnesses on a spider web without deforming or disrupting the web in a non-invasive, non-contact measurement, finding variation among discrete fibres, junctions and glue spots. Finally, we provide the stiffness changes that occur with supercontraction.

    View details for DOI 10.1038/NMAT3549

    View details for Web of Science ID 000315707200026

    View details for PubMedID 23353627

  • Shear-induced rigidity in spider silk glands APPLIED PHYSICS LETTERS Koski, K. J., McKiernan, K., Akhenblit, P., Yarger, J. L. 2012; 101 (10)

    View details for DOI 10.1063/1.4751842

    View details for Web of Science ID 000309072800084