Microjets are faster than a speeding bullet

When a shock wave travels through material and reaches a free surface, chunks of material can break away and fly off at high speeds. If there are any defects on the surface, the shock forms microjets that travel faster than a speeding bullet.

Understanding how these microjets form and how they interact with material help to improve spacecraft shielding and understanding a planetary impact.

In experiments performed by the MERIT project, lasers shock microscopic tin samples and create microjets that travel at several kilometers per second. Simulations are critical to understand the dynamics of jet formation.

Lawrence Livermore National Laboratory

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Opening the ‘black box’ of artificial intelligence

In February of 2013, Eric Loomis was driving around in the small town of La Crosse in Wisconsin, US, when he was stopped by the police. The car he was driving turned out to have been involved in a shooting, and he was arrested. Eventually a court sentenced him to six years in prison.

This might have been an uneventful case, had it not been for a piece of technology that had aided the judge in making the decision. They used COMPAS, an algorithm that determines the risk of a defendant becoming a recidivist. The court inputs a range of

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Titanium Atom That Exists in Two Places at Once in Crystal to Blame for Unusual Phenomenon

Researchers discover why a perfect crystal is not good at conducting heat, although it seemingly should be.

The crystalline solid BaTiS3 (barium titanium sulfide) is terrible at conducting heat, and it turns out that a wayward titanium atom that exists in two places at the same time is to blame.

This high-resolution scanning electron microscope (SEM) image of BaTiS3 crystals is overlaid with illustrations showing the orientation of individual atoms in the crystal. Despite the atomic perfection of the crystal, it is unexpectedly poor at transporting thermal energy. Image credit: Caltech/USC/ORNL

The discovery, made by researchers from Caltech, USC,

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Scanning electron microscope opens new avenues of research

During re-entry into the Earth’s atmosphere, temperatures on the surface of NASA’s space shuttle would reach a searing 1,650 degrees Celsius. Yet, inside the orbiter, astronauts sat safe and sound, protected from the fiery descent by special tiles that also preserved the shuttle’s critical components.

Engineers spent months developing those tiles, subjecting them to a process called materials characterization, in which the mechanical and microstructural properties of substances such as metals and composites are tested and examined under extreme conditions.

University of Miami researchers James Coakley and Giacomo Po know the process better than anyone. And now, their research—which ranges

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Photonics meets surface science in a cheap and accurate sensor for biological liquids

Skoltech researchers and their colleagues from Russia and Israel have come up with a new, simple and inexpensive method of testing liquid biological samples that can be further developed to work in clinical settings, including real-time testing during surgery. The paper was published in the journal Light: Science & Applications.

Image credit: Pixabay (Free Pixabay license)

The most common method of real-time diagnostic testing for biological samples (such as urine or saliva) that is used in the healthcare system, optical label-free sensors, are highly sensitive, but that sensitivity comes at a cost in terms of time and resources. Looking for

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How plants compete for underground real estate affects climate change and food production

You might have observed plants competing for sunlight — the way they stretch upwards and outwards to block each other’s access to the sun’s rays — but out of sight, another type of competition is happening underground. In the same way that you might change the way you forage for free snacks in the break room when your colleagues are present, plants change their use of underground resources when they’re planted alongside other plants.

In a paper published in Science (and featured on the cover), an international team of researchers led by Princeton graduate student Ciro Cabal sheds light

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