Salt crystals reveal surprise stretchiness

时间:2019-03-02 05:11:09166网络整理admin

By Sandrine Ceurstemont Biting down on grains of salt gives a crunchy sensation. But researchers at Sandia National Laboratories, New Mexico, US, have discovered that table salt can actually be ultra-elastic, as the video above shows. A team led by Jack Houston made the chance discovery while studying salt crystals to understand how they can be coated in water. They noticed that the diamond tip of their microscope was somehow being drawn to the salt surface. Tests confirmed that it was due to tiny nanowires of salt, extending out from the surface. Further tests yielded the video above, taken through a transmission electron microscope, which shows the nanowires behaving like taffy when touched with a gold probe. They can stretch to twice their original length. The discovery is another example of how the properties of materials, and things usually taken for granted such as the effects of momentum and gravity, can be drastically altered at the nanoscale. The Sandia team say their discovery will add to our understanding of how salt crystals behave, which could help explain how airborne sea salt can contribute to asthma, smog formation and ozone depletion. Journal reference: Nano Letters, DOI: 10.1021/nl9004805 More on these topics: