Credit: Berkeley Lab
Water clusters in sample fuel-cell components shrink over time in this sequence of images, produced by a 3-D imaging technique known as micro X-ray computed tomography. The water clusters were contained in a fibrous membrane that was exposed to different temperatures. The mean temperature began at about 104 degrees Fahrenheit and was gradually increased to about 131 degrees Fahrenheit. The top side of the images was the hotter side of the sample, and the bottom of the images was the colder side.