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    Salt can turn frozen water into a weak power source

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    Salt, ice and some oomph — these three simple ingredients are all that’s needed to make waste-free electricity, researchers report September 15 in Nature Materials. Straining a single cone-shaped piece of ice that’s slightly smaller than a black peppercorn and  25 percent salt by weight can output about 1 millivolt, while an array of 2,000 cones could produce 2 volts, or enough electrical potential to power a small red LED.

    The findings powerfully demonstrate the flexoelectric effect, a phenomenon where electricity is generated through the irregular deformation of a solid material. While the flexoelectricity produced by most materials is too weak for practical electrical systems, salted ice could someday provide a renewable source of  energy. More

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      Scientists re-create a legendary golden fabric from clam waste

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      Shimmering like spun gold, sea silk fabric is so lustrous that some believe it inspired the Greek legends of Jason’s quest for the Golden Fleece. For centuries, artisans in the Mediterranean have passed down the art of spinning the silk, which comes from the beardlike tufts of the giant clam Pinna nobilis. But the clam’s endangered species status has made it hard to keep the tradition alive.

      Now, scientists have re-created the legendary fabric using discarded parts of Atrina pectinata, a related clam species farmed extensively in South Korea for food. They’ve also identified the precise molecular structure and formation behind sea silk’s everlasting golden hue, the researchers report July 29 in Advanced Materials. More

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      A quantum computer goes to space

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      Senior physics writer Emily Conover has a Ph.D. in physics from the University of Chicago. She is a two-time winner of the D.C. Science Writers’ Association Newsbrief award and a winner of the Acoustical Society of America’s Science Communication Award. More

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      An injected gel could make drugs like Ozempic last longer

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      Meghan Rosen is a senior writer who reports on the life sciences for Science News. She earned a Ph.D. in biochemistry and molecular biology with an emphasis in biotechnology from the University of California, Davis, and later graduated from the science communication program at UC Santa Cruz. More

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      This paint ‘sweats’ to keep your house cool

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      A cool house without air conditioning may soon be possible.

      Scientists in Singapore have developed a new type of paint that reflects sunlight and cools surfaces by slowly evaporating water. Unlike other commercially available cooling paints, which are designed to repel water to protect the underlying material, the new one even works in hot, humid places, offering a low-energy way to stay cool, researchers report June 5 in Science.

      “The key is passive cooling,” which requires no energy input, says material scientist Li Hong In other words, it works without using electricity or mechanical systems. Right now, radiative cooling is the most common type of passive cooling used in materials, including certain paints. It works by reflecting sunlight and radiating heat from a surface such as walls or roofs, into the sky. But in humid places like Singapore, water vapor in the air traps heat near the surface, which prevents it from escaping into the atmosphere and keeps the surfaces warm.In response, Hong and two other material scientists from Nanyang Technological University developed a cement-based paint that combines three cooling strategies: radiative cooling, evaporative cooling, which our skin uses, and solar reflection. In the study, the scientists painted three small houses: one with regular white paint, one with commercial cooling paint that uses only radiative cooling and one with their new formula. After two years of sun and rain in Singapore, the first two paints had turned yellow. But “our paint was still white,” says coauthor Jipeng Fei. Unlike other colors, white helps materials maintain their high reflectivity and cooling performance. More

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      There’s no cheating this random number generator

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      If your name gets picked for jury duty, it’s because a computer used a random number generator to select it. The same goes for tax audits or when you opt for a quick pick lottery ticket. But how can you trust that the draw was truly fair? A new cheat-proof protocol for generating random numbers could provide that confidence — preventing hidden tampering or rigged outcomes, researchers report June 11 in Nature.

      “Having a public source of randomness that everyone trusts is important because the higher the stakes of an application or the more people involved, the more incentive there is to change or hack a random number generator,” says Gautam Kavuri, a physicist at the National Institute of Standards and Technology in Boulder, Colo. “This protocol verifies that random number generation is not being compromised.” More