The best material for Homemade Face Masks may be a combination of 2 Fabrics

Researchers report that a combination of cotton with natural silk or chiffon can effectively filter out aerosol particles – if the fit is good.

In the wake of the COVID-19 pandemic, the U.S. Centers for Disease Control and Prevention recommends that people wear masks in public. Because N95 and surgical masks are scarce and should be reserved for health care workers, many people are making their own coverings. Now, researchers report in ACS Nano that a combination of cotton with natural silk or chiffon can effectively filter out aerosol particles – if the fit is good.

SARS-CoV-2, the new coronavirus that causes COVID-19, is thought to spread mainly through respiratory droplets when an infected person coughs, sneezes, speaks or breathes...

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A New Way to Cool Down Electronic Devices, recover Waste Heat

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A hydrogel can cool off electronics and generate electricity from their waste heat. Scale bar, 2 cm.
Credit: Adapted from Nano Letters 2020, DOI: 10.1021/acs.nanolett.0c00800

Using electronic devices for too long can cause them to overheat, which might slow them down, damage their components or even make them explode or catch fire. Now, researchers reporting in ACS’ Nano Letters have developed a hydrogel that can both cool down electronics, such as cellphone batteries, and convert their waste heat into electricity.

Some components of electronic devices, including batteries, light-emitting diodes (known as LEDs) and computer microprocessors, generate heat during operation. Overheating can reduce the efficiency, reliability and lifespan of devices, in addition to wasting energy...

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Engineers’ ‘Nanocardboard’ Flyers could serve as Martian Atmospheric Probes

Despite weighing about a third of a milligram, Penn Engineers are now testing their “nanocardboard flyers” ability to lift payloads. In this artist’s conception, fleets of flyers could be launched from ground-based rovers and steered with lasers to collect samples. Planets and moons with thin atmospheres and low gravities would enhance these flyers’ ability to levitate by shooting air through their corrugated channels.

Engineers are suggesting a new way to explore the sky: tiny aircraft that weigh about as much as a fruit fly and have no moving parts. These flyers are plates of ‘nanocardboard,’ which levitate when bright light is shone on them...

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Milky Way could be Catapulting Stars into its Outer Halo

Milky Way could be catapulting stars into its outer halo, UCI astronomers say
A simulated galaxy image from the FIRE-2 project, representing a structure spanning more than 200,000 light years, shows the prominent plumes of young blue stars born in gas that was originally rotating and then blown radially outward by supernova explosions. Courtesy of Sijie Yu / UCI

Findings may change fundamental thinking about star system formation, dynamics. University of California, Irvine astronomers and others have shown that clusters of supernovas can cause the birth of scattered, eccentrically orbiting suns in outer stellar halos, upending commonly held notions of how star systems have formed and evolved over billions of years.

Hyper-realistic, cosmologically self-consistent computer simulations from the Feedback in Realistic Environments 2 project enabled the scientists ...

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