Washington:  Defying gravitational forces, an Indian-origin scientist-led team has developed a new way of making surfaces that can actively control how fluids or particles move across them. The discovery may enable new kinds of biomedical or microfluidic devices or solar panels that could automatically clean themselves of dust and grit. “Most surfaces are passive. They rely on gravity or other forces to move fluids or particles,” said Kripa Varanasi, an […]

Geologists have discovered the secret that gives dramatic natural sandstone monuments their shape: gravity. By studying cubes of sand in the lab, they showed that areas squeezed by vertical stress are protected from erosion, while others wash away. The process had proved difficult to study, because natural slabs of sandstone erode over millions of years. The key to the experiments, published in Nature Geoscience, was an unusual “locked sand” dug […]