Materials Science

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

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

When egg prices are hard-boiling your temper, it’s important to make sure that each egg you make is the best it can possibly be. But when your egg white is cooked, your egg yolk is often still a runny mess. Once the yolk is cooked, the white is rubbery. The solution is a method of periodic cooking, researchers report February 6 in Communications Engineering. And true eggcellence, they say, requires only boiling water, slightly warm water, an egg — and 32 minutes of patience.

The challenge of cooking an egg is that the yolk and the albumen — or white — have different compositions, says Emilia Di Lorenzo, a chemical engineer at the University of Naples Federico II in Italy. The result is that the proteins in each part of the egg denature — or fall apart — at different temperatures. Yolk proteins cook at 65° Celsius, while those in the white cook at 85° C. More

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

The world record for the thinnest pasta has been shattered, though the new, narrow noodles are better suited to wound dressings than the dinner table.

From white flour, researchers made starch-rich nanofibers that are about 370 nanometers thick, on average — or about two hundredths the thickness of a human hair. The nano-noodles could be used in biodegradable bandages, chemist Adam Clancy and colleagues reported October 30 in Nanoscale Advances.

To make the noodle “dough,” the scientists mixed the flour with formic acid, a liquid that helps uncoil the long starch molecules in the flour. “Normally, if you want to cook starch, then you use water and heat to break up the tight packing of starch,” says Clancy, of University College London. “We do that chemically with formic acid. So we effectively pickle it instead of cooking it.” More

Electric vehicles promise to help wean us off of fossil fuels, but they introduce a new problem: how to get enough of the lithium that EV batteries require (SN: 5/7/19).

Materials scientist Chong Liu of the University of Chicago has some ideas. Existing technology can extract lithium only from sources with highly concentrated ions, like hard rocks or underground deposits of salty water called brines. Not only will those sources not be enough to meet demand, but mining them also comes with environmental consequences (SN: 3/15/22). More

Sometimes science fiction does inspire science research. À la Jurassic Park’s entombed mosquito, scientists have developed a method to store DNA in an amberlike material and still extract it easily hours later. This storage method is cheaper and faster than existing options, the researchers report in the June Journal of the American Chemical Society.

If you want to store information for a very long time, possibly forever, DNA is the way to do it, says James Banal, a chemist at MIT and technical director of a biotechnology company called Cache DNA, headquartered in San Carlos, Calif. DNA stores the genetic information of millions of organisms, but it can potentially be used to store any kind of information, including digital data such as text, photos, videos and more (SN: 10/2/19). More