Tag Archives: crystallization

Misleading mineral may have led to overestimate of water in moon

Discovery of hydrogen-rich apatite in lunar rocks hinted at more watery past. Think again, says UCLA’s Jeremy Boyce.

The amount of water present in the moon may have been overestimated by scientists studying the mineral apatite, says a team of researchers led by Jeremy Boyce of the UCLA Department of Earth, Planetary and Space Sciences.

Boyce and his colleagues created a computer model to accurately predict how apatite would have crystallized from cooling bodies of lunar magma early in the moon’s history. Their simulations revealed that the unusually hydrogen-rich apatite crystals observed in many lunar rock samples may not have formed within a water-rich environment, as was originally expected. (more…)

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Magma can survive in upper crust for hundreds of millennia

Reservoirs of silica-rich magma – the kind that causes the most explosive volcanic eruptions – can persist in Earth’s upper crust for hundreds of thousands of years without triggering an eruption, according to new University of Washington modeling research.

That means an area known to have experienced a massive volcanic eruption in the past, such as Yellowstone National Park, could have a large pool of magma festering beneath it and still not be close to going off as it did 600,000 years ago.

“You might expect to see a stewing magma chamber for a long period of time and it doesn’t necessarily mean an eruption is imminent,” said Sarah Gelman, a UW doctoral student in Earth and space sciences. (more…)

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Molecular Scientists Reveal Extraordinary Properties of Ordinary Glasses

Technologically valuable ultrastable glasses can be produced in days or hours with properties corresponding to those that have been aged for thousands of years, computational and laboratory studies have confirmed.

Aging makes for higher quality glassy materials because they have slowly evolved toward a more stable molecular condition. This evolution can take thousands or millions of years, but manufacturers must work faster. Armed with a better understanding of how glasses age and evolve, researchers at the universities of Chicago and Wisconsin-Madison raise the possibility of designing a new class of materials at the molecular level via a vapor-deposition process. (more…)

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Modeling the Breaking Points of Metallic Glasses

Mathematical methods developed by a Berkeley Lab researcher help explain why liquid metals have wildly different breaking points, depending on how they are made

Metallic glass alloys (or liquid metals) are three times stronger than the best industrial steel, but can be molded into complex shapes with the same ease as plastic. These materials are highly resistant to scratching, denting, shattering and corrosion. So far, they have been used in a variety of products from golf clubs to aircraft components. And, some smartphone manufacturers are even looking to cast their next-generation phone cases out of it.

But despite their potential, the mechanical properties of these substances are still a scientific mystery. One lingering question is why they have such wildly different toughness and breaking points, depending on how they are made. Although this may not be a huge concern for small applications like smartphone cases it will be extremely important if these materials are ever used in structural applications where they would need to support large loads. (more…)

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A Clock that Will Last Forever

Berkeley Lab Researchers Propose a Way to Build the First Space-Time Crystal

Imagine a clock that will keep perfect time forever, even after the heat-death of the universe. This is the “wow” factor behind a device known as a “space-time crystal,” a four-dimensional crystal that has periodic structure in time as well as space. However, there are also practical and important scientific reasons for constructing a space-time crystal. With such a 4D crystal, scientists would have a new and more effective means by which to study how complex physical properties and behaviors emerge from the collective interactions of large numbers of individual particles, the so-called many-body problem of physics. A space-time crystal could also be used to study phenomena in the quantum world, such as entanglement, in which an action on one particle impacts another particle even if the two particles are separated by vast distances.

A space-time crystal, however, has only existed as a concept in the minds of theoretical scientists with no serious idea as to how to actually build one – until now. An international team of scientists led by researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) has proposed the experimental design of a space-time crystal based on an electric-field ion trap and the Coulomb repulsion of particles that carry the same electrical charge. (more…)

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Touch of Gold Improves Nanoparticle Fuel-Cell Reactions

Chemists at Brown University have created a triple-headed metallic nanoparticle that reportedly performs better and lasts longer than any other nanoparticle catalyst studied in fuel-cell reactions. The key is the addition of gold: It yields a more uniform crystal structure while removing carbon monoxide from the reaction. Results published in the Journal of the American Chemical Society.

PROVIDENCE, R.I. [Brown University] — Advances in fuel-cell technology have been stymied by the inadequacy of metals studied as catalysts. The drawback to platinum, other than cost, is that it absorbs carbon monoxide in reactions involving fuel cells powered by organic materials like formic acid. A more recently tested metal, palladium, breaks down over time. (more…)

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