Faster, Smaller, more Powerful Computer Chips: Hafnia dons a new face

The authors observed in real-time the transformation of a HfO2 nanorod from its room temperature to tetragonal phase, at 1000° less than its bulk temperature. Nanorod surfaces and twin boundary defects (pictured here) serve to kinetically trap this phase.

The authors observed in real-time the transformation of a HfO2 nanorod from its room temperature to tetragonal phase, at 1000° less than its bulk temperature. Nanorod surfaces and twin boundary defects (pictured here) serve to kinetically trap this phase.

Materials research creates potential for improved computer chips and transistors. The inorganic compound hafnium dioxide commonly used in optical coatings has several polymorphs, including a tetragonal form with highly attractive properties for computer chips and other optical elements. However, because this form is stable only at temperatures above 3100F – scientists have had to make do with its more limited monoclinic polymorph. Until now...

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Is this the ‘Holey’ Grail of Batteries?

This visualisation shows layers of graphene used for membranes. Credit: University of Manchester

This visualisation shows layers of graphene used for membranes. Credit: University of Manchester

In a battery system, electrodes containing porous graphene scaffolding offer a substantial improvement in both the retention and transport of energy, a new study reveals. Usually, techniques to improve the density of stored charge conflict with those that aim to improve the speed at which ions can move through a material. Nanostructured materials have shown extraordinary promise for electrochemical energy storage, but these materials are usually limited to laboratory cells with ultrathin electrodes and very low mass loadings.

Hongtao Sun et al. overcome this obstacle by incorporating holey graphene into a niobium pentoxide electrode. The nanopores facilitate rapid ion transport...

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Primitive Atmosphere discovered around ‘Warm Neptune’

The atmosphere of the distant “warm Neptune” HAT-P-26b, illustrated here, is unexpectedly primitive, composed primarily of hydrogen and helium. By combining observations from NASA’s Hubble and Spitzer space telescopes, researchers determined that, unlike Neptune and Uranus, the exoplanet has relatively low metallicity, an indication of the how rich the planet is in all elements heavier than hydrogen and helium. Credit: NASA/GSFC

The atmosphere of the distant “warm Neptune” HAT-P-26b, illustrated here, is unexpectedly primitive, composed primarily of hydrogen and helium. By combining observations from NASA’s Hubble and Spitzer space telescopes, researchers determined that, unlike Neptune and Uranus, the exoplanet has relatively low metallicity, an indication of the how rich the planet is in all elements heavier than hydrogen and helium. Credit: NASA/GSFC

A pioneering new study uncovering the ‘primitive atmosphere’ surrounding a distant world could provide a pivotal breakthrough in the search to how planets form and develop in far-flung galaxies...

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Distance at which Supernova would spark Mass extinctions on Earth

A simulation of iron-60 atoms dispersed by multiple supernovae close to the solar system 2.2 million years ago. Some of that iron still lies at the bottom of the oceans and on the moon.

A simulation of iron-60 atoms dispersed by multiple supernovae close to the solar system 2.2 million years ago. Some of that iron still lies at the bottom of the oceans and on the moon.

In 2016, researchers published “slam dunk” evidence, based on iron-60 isotopes in ancient seabed, that supernovae buffeted the Earth – one of them about 2.6 million years ago. Melott has followed up since those findings with an examination of the effects of the supernovae on Earth’s biology. In new research to appear in Astrophysical Journal, the KU researcher and colleagues argue the estimated distance of the supernova thought to have occurred roughly 2.6 million years ago should be cut in half.

“There’s even more evidence of that supernova now,” he said...

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