- News Home
17 April 2014 12:48 pm ,
Vol. 344 ,
Officials last week revealed that the U.S. contribution to ITER could cost $3.9 billion by 2034—roughly four times the...
An experimental hepatitis B drug that looked safe in animal trials tragically killed five of 15 patients in 1993. Now,...
Using the two high-quality genomes that exist for Neandertals and Denisovans, researchers find clues to gene activity...
A new report from the Intergovernmental Panel on Climate Change (IPCC) concludes that humanity has done little to slow...
Astronomers have discovered an Earth-sized planet in the habitable zone of a red dwarf—a star cooler than the sun—500...
Three years ago, Jennifer Francis of Rutgers University proposed that a warming Arctic was altering the behavior of the...
- 17 April 2014 12:48 pm , Vol. 344 , #6181
- About Us
ScienceShot: Water Floats on Oil
5 April 2012 11:28 am
Two years ago, the explosion of the Deepwater Horizon oil rig covered hundreds of square miles of the Gulf of Mexico with oil (main image). The oil floated because it is less dense, and therefore lighter, than water. But now scientists say that water can sometimes float on oil—and their findings, which were published last month in Langmuir, could help to mop up oil slicks like the one created by the 2010 disaster. Using a theoretical model, the scientists calculated the forces acting on water when it is dripped onto an oil surface. Taking into account surface tension, the property that allows some insects to walk on water, they showed that a water droplet can "hang" from the oil's surface. The oil surface droops like a rubber membrane, allowing the above air—which is much lighter than oil and water—to extend beneath the surface's average level. With help from the surface tension, this air pocket balances the weight of the water droplet, preventing it from sinking. The scientists confirmed the model's predictions in tests and found that water droplets up to 170 microliters in volume could float on oil (inset image and video). Such water droplets would be large enough to harbor natural microbes that consume oil. If they were sprayed over an oil slick, the scientists say, the cleanup process could be much faster.
See more ScienceShots.