University of California, Irvine scientists have discovered a one-dimensional nanoscale material whose color changes as temperature changes. "We found that we can make really small and sensitive thermometers," said Maxx Arguilla, one of the scientists involved in this study. Arguilla likened the thermometers to "nano-scale mood rings," referring to the jewelry that changes color depending on the wearer's body temperature. But instead of simply taking a qualitative temperature reading, the changes in the color of these materials "can be calibrated and used to optically take temperature readings at the nanoscale," Arguilla said.
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