Category Technology/Electronics

Jan Genzer et al. Sequential Self-folding of Polymer Sheets. Science Advances, March 2017 DOI: 10.1126/sciadv.1602417

Inspired by origami, North Carolina State University researchers have found a way to remotely control the order in which a 2D sheet folds itself into a 3D structure. “The sequence of folding is important in life as well as in technology,” says Genzer, the S. Frank and Doris Culberson Distinguished Professor of Chemical and Biomolecular Engin

eering at NC State. “On small length scales, sequential folding via molecular machinery enables DNA to pack efficiently into chromosomes and assists proteins to adopt a functional conformation. On large length scales, sequential folding via motors helps solar panels in satellites and space shuttles unfold in space...

This image from a scanning electron microscope shows a cross section of an object printed using cellulose. The inset shows the surface of the object. Credit: Courtesy of the researchers

Thanks to new research at MIT, cellulose may become an abundant material to print with – potentially providing a renewable, biodegradable alternative to the polymers currently used in 3D printing materials. “Cellulose is the most abundant organic polymer in the world,” says MIT postdoc Sebastian Pattinson. “Cellulose and its derivatives are used in pharmaceuticals, medical devices, as food additives, building materials, clothing – all sorts of different areas. And a lot of these kinds of products would benefit from the kind of customization that additive manufacturing [3-D printing] enables.”

Meanwhile, 3D ...

The team’s nanocones (scanning electron microscope image, (a)) were inspired by the nanotexture found on cicada wings (atomic force microscopy image, (b)). The middle plot (c) shows that the nanocones (red squares) are far less adhesive to warm water than the nanocylinders (blue circles). Because of the nanocone geometry, water droplets beneath a large drop can be reabsorbed (d) and small droplets condensing in cones can reconfigure at the top of the cones (e). Credit: Nature Materials

Nanotextures inspired by cone-shaped structures on cicada wings could inform new designs for materials prone to fogging, such as car and aircraft windshields. Several years ago, scientists at the U.S...

Schematic diagram of the molecular robot. Molecular actuators work inside the robot, and the shape of the artificial cell membrane, which are bodies, are changed. When a DNA signal is input, the “molecular clutch,” which transmits the force from the actuator, controls the shape-changing behavior. (B) Microscopy images of molecular robots. When the input DNA signal was “stop,” the clutch was turned “OFF,” and consequently, the shape-changing behavior was terminated (left side). The initiation of the shape-changing behavior when the DNA signal input was “start” was also confirmed (right side). Scale bar: 20 ?m. The white arrow indicates the molecular actuator part that transforms the membrane.
Credit: Yusuke Sato

Tohoku University and Japan Advanced Institute of Science and Technology researc...