Reference Terms
from Wikipedia, the free encyclopedia
Ultrasound
Ultrasound is sound with a frequency greater than the upper limit of human hearing, approximately 20 kilohertz (20,000 hertz).
Note: The above text is excerpted from the Wikipedia article "Ultrasound", which has been released under the GNU Free Documentation License.
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Matter & Energy News
April 29, 2025
Apr. 28, 2025 — A technique to cool the planet, in which particles are added to the atmosphere to reflect sunlight, would not require developing special aircraft but could be achieved using existing large planes, according to a new modelling ...
Apr. 23, 2025 — Inspired by the movements of a tiny parasitic worm, engineers have created a 5-inch soft robot that can jump as high as a basketball hoop. Their device, a silicone rod with a carbon-fiber spine, can leap 10 feet high even though it doesn't have ...
Apr. 23, 2025 — Engineers developed a technique to grow and peel ultrathin 'skins' of electronic material that could be used in applications such as night-vision eyewear and autonomous driving in foggy ...
Apr. 11, 2025 — A team of researchers reported the first direct observation of a surprising quantum phenomenon predicted over half a century ago known as a superradiant phase transition, which occurs when two groups of quantum particles begin to fluctuate in a ...
Latest Headlines
updated 12:56 pm ET
Apr. 28, 2025 — Crystals -- from sugar and table salt to snowflakes and diamonds -- don't always grow in a straightforward way. Researchers have now captured this journey from amorphous blob to orderly structures. ...
Apr. 28, 2025 — Researchers have created a light-powered soft robot that can carry loads through the air along established tracks, similar to cable cars or aerial trams. The soft robot operates autonomously, can ...
Apr. 28, 2025 — Scientists aren't comedians, but it turns out a joke or two can go a long way. That's according to a new study that found when researchers use humor in their communication -- particularly online -- ...
Apr. 28, 2025 — With more than 181.5 billion tons of wood produced globally each year, a new method could revolutionize how we build sustainably. By infusing red oak with ferrihydrite using a simple, low-cost ...
Apr. 28, 2025 — Researchers have developed a new catalyst design capable of pushing the projected fuel cell catalyst lifespans to 200,000 hours. The research marks a ...
Apr. 23, 2025 — Addressing the challenges of fragrance design, researchers have developed an AI model that can automate the creation of new fragrances based on user-defined scent descriptors. The model uses mass ...
Apr. 25, 2025 — Researchers found a strategy to create catalysts that make the production of hydrogen for clean fuel more efficient and ...
Apr. 25, 2025 — Historically, small molecule drugs have been precisely designed down to the atomic scale. Considering their relatively large complex structures, nanomedicines have lagged behind. Researchers argue ...
Apr. 25, 2025 — Researchers have developed a new therapy that can be injected intravenously right after a heart attack to promote healing and prevent heart failure. The therapy both prompts the immune system to ...
Apr. 25, 2025 — Many products in the modern world are in some way fabricated using computer numerical control (CNC) machines, which use computers to automate machine operations in manufacturing. While simple in ...