Stretching and folding of 2-nanometer hydrocarbon rods

Stretching and folding of 2-nanometer hydrocarbon rods.

Linear alkanes CnH2n+2 in vacuum isolation are finite models for an infinite polyethylene chain. Using spontaneous Raman scattering in supersonic jet expansions for n = 13-21 in different spectral ranges, we determine the minimal chain length nh for the cohesion-driven folding of the preferred extended all-trans conformation into a hairpin structure. We treat fully stretched all-trans alkanes a...

Stretching Folding Instablility and Nanoemulsion

Asymptotic Analysis of Torsional and Stretching Modes of Thin Rods

In this article, we show that a class of high frequencies of the threedimensional linearized elasticity system in a thin rod and their associated eigenfunctions converge in a precise sense, as the area of the cross section of the rod goes to zero. The limit model is a coupled one-dimensional problem giving the classical equations for torsion and stretching modes in rods.

Stretching and folding in finite time.

Complex flows mix efficiently, and this process can be understood by considering the stretching and folding of material volumes. Although many metrics have been devised to characterize stretching, fewer are able to capture folding in a quantitative way in spatiotemporally variable flows. Here, we extend our previous methods based on the finite-time curving of fluid-element trajectories to nonze...

Stretching lattice models of protein folding.

A new class of experiments that probe folding of individual protein domains uses mechanical stretching to cause the transition. We show how stretching forces can be incorporated in lattice models of folding. For fast folding proteins, the analysis suggests a complex relation between the force dependence and the reaction coordinate for folding.