Phospholipids containing diacetylene moieties along their hydrocarbon chains have been extensively studied for their ability to self-assemble into tubule structures from aqueous and aqueous/alcohol solvents. 1,2-Bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine (DC8,9PC) has previously been shown to form hollow microtubules of length 50-200 μm and average diameter of approximately 0.5 μm. I...

Mixing patterns in agitated vessels equipped with various types of helical ribbon impellers are observed by using capsules of liquid crystal as a tracer. As a result, the optimumgeometrical variables for the mixing process are provided and the results explained by considering the relation between the mixing pattern and impeller geometry. A mathematical model is developed and applied in order to...

The electrospinning of gelatin with tunable fiber morphology from round to flat/ribbon was shown, and the detailed studies were conducted to correlate the fiber morphology with electrospinning process parameters and gelatin concentration in electrospinning solution. Particularly, variations in the applied voltage and the concentration of gelatin led to the transition of fiber shape from round t...

Streamline seeding algorithms have a long and rich history dating back over two decades. And in recent years algorithms for stream surface placement have been developed. However, stream ribbons have been generally overlooked. We present, to our knowledge, the first stream ribbon seeding strategy. Stream ribbons are a tool for visualizing vector fields and are a common extension of streamlines w...

We provide a geometric-mechanical model for calculating equilibrium configurations of chemical systems that self-assemble into chiral ribbon structures. The model is based on incompatible elasticity and uses dimensionless parameters to determine the equilibrium configurations. As such, it provides universal curves for the shape and energy of self-assembled ribbons. We provide quantitative predi...

Helices are the most abundant secondary structural elements in proteins and the structural forms assumed by double stranded DNAs (dsDNA). Though the mathematical expression for a helical curve is simple, none of the previous models for the biomolecular helices in either proteins or DNAs use a genuine helical curve, likely because of the complexity of fitting backbone atoms to helical curves. In...