Gizmo

 作者:俞撺菔     |      日期:2019-03-01 01:08:11
Etching nanoscale grooves into boat hulls could make them go faster and use less fuel. Researchers at UT-Battelle, a non-profit organisation in Tennessee, covered a hull with smooth, tough borosilicate glass. They then created a pattern of ridges a few millimetres deep across the material and etched nanoscale grooves into the walls of these ridges. As the hull moves through the water, air bubbles become trapped in the grooves, providing a low-friction cushion. London hairdressers dispose of 10,400 tonnes of human hair every year,