Cheap, Nontoxic Carbon Nanodots poised to be Quantum Dots of the Future

Tiny fluorescent semiconductor dots, called quantum dots, are useful in a variety of health and electronic technologies but are made of toxic, expensive metals. Nontoxic and economic carbon-based dots are easy to produce, but they emit less light. A new study that uses ultrafast nanometric imaging found good and bad emitters among populations of carbon dots. This observation suggests that by selecting only super-emitters, carbon nanodots can be purified to replace toxic metal quantum dots in many applications, the researchers said.

The findings, published in the Proceedings of the National Academy of Sciences, brought together researchers from the University of Illinois Urbana-Champaign and the University of Delaware, Baltimore County in a collaborative project through the Beckman ...

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Most Distant Quasar with Powerful Radio Jets discovered

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With the help of the European Southern Observatory’s Very Large Telescope (ESO’s VLT), astronomers have discovered and studied in detail the most distant source of radio emission known to date. The source is a “radio-loud” quasar — a bright object with powerful jets emitting at radio wavelengths — that is so far away its light has taken 13 billion years to reach us. The discovery could provide important clues to help astronomers understand the early Universe.

With the help of the European Southern Observatory’s Very Large Telescope (ESO’s VLT), astronomers have discovered and studied in detail the most distant source of radio emission known to date...

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Reduced Heat Leakage Improves Wearable Health Device

Image of flexible device.
NC State’s flexible heat harvesting device shows better efficiency at retaining heat to power the device. Photo courtesy of Mehmet Ozturk.

North Carolina State University engineers continue to improve the efficiency of a flexible device worn on the wrist that harvests heat energy from the human body to monitor health.

In a paper published in npj Flexible Electronics, the NC State researchers report significant enhancements in preventing heat leakage in the flexible body heat harvester they first reported in 2017 and updated in 2020. The harvesters use heat energy from the human body to power wearable technologies — think of smart watches that measure your heart rate, blood oxygen, glucose and other health parameters — that never need to have their batteries recharged...

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Life’s rich pattern: Researchers use Sound to Shape the Future of Printing

material swirling in a circle of speakers
Utrasound and computer algorithms control how material settles into shape

Researchers in the UK have developed a way to coax microscopic particles and droplets into precise patterns by harnessing the power of sound in air. The implications for printing, especially in the fields of medicine and electronics, are far-reaching.

The scientists from the Universities of Bath and Bristol have shown that it’s possible to create precise, pre-determined patterns on surfaces from aerosol droplets or particles, using computer-controlled ultrasound. A paper describing the entirely new technique, called ‘sonolithography’, is published in Advanced Materials Technologies.

Professor Mike Fraser from the Department of Computer Science at the University of Bath, explained: “The power of ultrasound h...

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