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A new crystal-based detector could soon change how doctors see inside the body. Developed by scientists in the U.S. and China, the device captures gamma rays with unprecedented clarity, promising faster, safer, and more affordable scans. (Artist’s concept). Credit: Shutterstock ================================================================================= A new detector aims to reduce costs while improving the quality of nuclear medicine. Physicians use nuclear medicine techniques such as SPECT scans to observe how the heart pumps, follow patterns of blood flow, and identify diseases that are otherwise hidden deep within the body. Current scanners, however, rely on detectors that are both costly and difficult to manufacture....

Researchers say they've recovered a mineral from deep inside the Earth — one they thought would never see the light of day. Scientists at the University of Nevada, Las Vegas, named the mineral "davemaoite," after Ho-kwang "Dave" Mao, a retired experimental geophysicist whose influence on the field is still felt today. "It's an opportunity to give him credit for his big contributions," said Oliver Tschauner, a mineralogist who led a study of the rare mineral, in an interview with NPR's Morning Edition. No one ever expected to see the mineral on the Earth's surface. That's because deep-Earth minerals like davemaoite...

Perovskite promises to be less expensive and more efficient than silicon—and several companies say they’re close to producing it at scale. SAULE TECHNOLOGIES ==================================================================================== Testing perovskite solar cells in the lab used to require a decent pair of running shoes. The materials fell apart so quickly that scientists would bolt from where they made the cells to where they tested them, trying to measure their performance before the cells degraded in their hands—usually within a couple of minutes. Perovskites have long enchanted researchers with the promise of producing inexpensive, ultra-efficient solar cells. And now several companies are making major strides...

Researchers drew attention three years ago when they reported that a two-dimensional perovskite—a material with a specific crystal structure—composed of cesium, lead and bromine emitted a strong green light. Crystals that produce light on the green spectrum are desirable because green light, while valuable in itself, can also be relatively easily converted to other forms that emit blue or red light, making it especially important for optical applications ranging from light-emitting devices to sensitive diagnostic tools. But there was no agreement about how the crystal, CsPB2Br5, produced the green photoluminescence. Now, however, researchers from the United States, Mexico and China,...

Solar cells made from an inexpensive and increasingly popular material called perovskite can more efficiently turn sunlight into electricity using a new technique to sandwich two types of perovskite into a single photovoltaic cell. Perovskite solar cells are made of a mix of organic molecules and inorganic elements that together capture light and convert it into electricity, just like today’s more common silicon-based solar cells. Perovskite photovoltaic devices, however, can be made more easily and cheaply than silicon and on a flexible rather than rigid substrate. The first perovskite solar cells could go on the market next year, and some...