It’s not ready to replace cement just yet, but it’s really promising.
Category: materials – Page 24
Your cells can ‘hear’: Uncovering the relationship between life and sound
There’s a sensation that you experience—near a plane taking off or a speaker bank at a concert—from a sound so total that you feel it in your very being. When this happens, not only do your brain and ears perceive it, but your cells may also.
Technically speaking, sound is a simple phenomenon, consisting of compressional mechanical waves transmitted through substances which exist universally in the non-equilibrated material world. Sound is also a vital source of environmental information for living beings, while its capacity to induce physiological responses at the cell level is only just beginning to be understood.
Following on from previous work from 2018, a team of researchers at Kyoto University have been inspired by research in mechanobiology and body-conducted sound—the sound environment in body tissues —indicating that acoustic pressure transmitted by sound may be sufficient to induce cellular responses.
Two Superconductivity States Coincide in Ultrathin Films
To understand superconductors, researchers explore their behavior at the limits of superconductivity, such as at high temperature or under strong magnetic field. New experiments investigate superconductivity at the limits of thickness, finding unexpected vortex behavior in ultrathin films [1]. Using a high-resolution magnetic imaging technique, Nofar Fridman from the Hebrew University of Jerusalem and colleagues measured vortex sizes in superconducting samples of various thicknesses and found larger-than predicted vortices in films made up of six or fewer atomic layers. The results suggest that thin superconductors host two superconducting states: one in the bulk of the material, the other confined to the surface layers. This behavior challenges our present understanding of how superconductors behave.
When a superconductor is exposed to an external magnetic field, it generates electrical screening currents, which generate a counter magnetic field, explains team member Yonathan Anahory from the Hebrew University of Jerusalem. The net effect is the external field lines bend around the superconductor without penetrating the material.
However, the situation changes in thin superconducting films, where the material’s ability to completely expel magnetic fields is weakened. Instead of being fully excluded, the field enters the film through narrow columns, called vortices, around which superconducting screening currents flow. Inside each vortex, there is exactly one quantum of magnetic flux.
Lithium oxide sublimation opens doors for cheaper and quicker battery manufacturing
A common lithium salt has revealed new possibilities for manufacturing cheaper, longer-lasting battery materials.
Scientists develop new method to measure and predict hydrogen bond strength in confined water
A breakthrough by researchers at The University of Manchester sheds light on one of nature’s most elusive forces, with wide-reaching implications for medicine, energy, climate modeling and more. The researchers have developed a method to precisely measure the strength of hydrogen bonds in confined water systems, an advance that could transform our understanding of water’s role in biology, materials science, and technology.
The work, published in Nature Communications, introduces a fundamentally new way to think about one of nature’s most important but difficult-to-quantify interactions.
Hydrogen bonds are the invisible forces that hold water molecules together, giving water its unique properties, from high boiling point to surface tension, and enabling critical biological functions such as protein folding and DNA structure. Yet despite their significance, quantifying hydrogen bonds in complex or confined environments has long been a challenge.
Tectonic Plates Have a Memory — And It’s Changing What We Know About Earth
New research has found that variations in rock composition within oceanic plates, caused by ancient tectonic processes, can significantly affect the path and speed of these plates as they sink into Earth’s mantle.
At depths between 410 and 660 kilometers lies the mantle transition zone (MTZ), a key boundary layer that regulates the movement of material into the planet’s deeper interior. When subducting plates, those that dive beneath others, encounter large concentrations of basalt within the MTZ, their descent can slow down or even stall, rather than continuing smoothly into the lower mantle. While basalt-rich regions in the MTZ have been observed before, their origins have remained uncertain until now.
Rare crystal shape found to increase the strength of 3D-printed metal
Andrew Iams saw something strange while looking through his electron microscope. He was examining a sliver of a new aluminum alloy at the atomic scale, searching for the key to its strength, when he noticed that the atoms were arranged in an extremely unusual pattern.
“That’s when I started to get excited,” said Iams, a materials research engineer, “because I thought I might be looking at a quasicrystal.”
Not only did he find quasicrystals in this aluminum alloy, but he and his colleagues at the National Institute of Standards and Technology (NIST) found that these quasicrystals also make it stronger. They have published their findings in the Journal of Alloys and Compounds.
Stainless steel strengthened: Twisting technique creates submicron ‘anti-crash wall’
A combined team of metallurgists, materials scientists and engineers from the Chinese Academy of Sciences, Shandong University and the Georgia Institute of Technology has developed a way to make stainless steel more resistant to metal fatigue. In their study published in the journal Science, the group developed a new twisting technique that functions as an “anti-crash wall” in the steel, giving it much more strength and resistance to cyclic creep.
Metal can experience fatigue when bent many times, leading to breaking. When this occurs in critical applications, it can result in catastrophic accidents such as bridge failures. Because of that, scientists have for many years been working to reduce or prevent stress levels in metals. In this new effort, the researchers found a way to dramatically improve the strength of a type of stainless steel while also boosting its resistance to what is known as cycle creep, where fatigue occurs due to ratcheting, a form of repeated bending.
The new technique involved repeatedly twisting a sample of 304 austenitic stainless steel in a machine in certain ways. This led to spatially grading the cells that made up the metal, resulting in the build-up of what the team describes as a submicron-scale, three-dimensional, anti-crash wall. Under a microscope, the researchers found an ultra-fine, sub-10 nanometer, coherent lamellar structure that slowed dislocation by preventing stacking faults.