A lithium-ion battery made from three droplets of hydrogel is the smallest soft battery of its kind – and it could be used in biocompatible and biodegradable implants.
Category: materials – Page 39
Recently, two independent research groups have shown that the brain codes for zero much as it does for other numbers, on a mental number line. But, one of the studies found, zero also holds a special status in the brain.
In recent years, research started to uncover how the human brain represents numbers, but no one examined how it handles zero. Now two independent studies, led by Nieder and Barnett, respectively, have shown that the brain codes for zero much as it does for other numbers, on a mental number line. But, one of the studies found, zero also holds a special status in the brain.
“The fact that [zero] represents nothing is a contradiction in itself,” said Carlo Semenza, a professor emeritus of neuroscience at the University of Padua in Italy who wasn’t involved in either study. “It looks like it is concrete because people put it on the number line — but then it doesn’t exist. … That is fascinating, absolutely fascinating.”
The new studies are the first to reveal what goes on in the brain when a person thinks about zero, and they bring up broader questions about how the mind handles absence — a pursuit that would have pleased Jean-Paul Sartre, the 20th-century existentialist who claimed that “nothingness carries being in its heart.”
Researchers Tomohito Amano and Shinji Tsuneyuki of the University of Tokyo with Tamio Yamazaki of CURIE (JSR-UTokyo Collaboration Hub) have developed a new machine learning model to predict the dielectric function of materials, rather than calculating from first-principles.
High-temperature superconductivity is one of the great mysteries of modern physics: Some materials conduct electrical current without any resistance—but only at very low temperatures. Finding a material that remains superconducting even at room temperature would spark a technological revolution. People all over the world are therefore working on a better, more comprehensive understanding of such materials.
Researchers at the University of California, Berkeley, have developed a new material for direct air capture that outperforms existing technologies.
This covalent organic framework (COF) can effectively remove carbon dioxide from ambient air, mimicking the absorptive capacity of trees but at a significantly accelerated rate.
Carbon Capture Challenges
Researchers Takuma Nakamura, Kazuki Hashimoto, and Takuro Ideguchi of the Institute for Photon Science and Technology at the University of Tokyo have increased by 100-fold the measurement rate of Raman spectroscopy, a common technique for measuring the “vibrational fingerprint” of molecules in order to identify them.
As the measurement rate has been a major limiting factor, this improvement contributes to advancements in many fields that rely on identifying molecules and cells, such as biomedical diagnostics and material analytics. The findings were published in the journal Ultrafast Science.
Identifying various types of molecules and cells is a crucial step in both basic and applied science. Raman spectroscopy is a widely used measurement technique for this purpose. When a laser beam is projected onto molecules, the light interacts with the vibrations and rotations of molecular bonds, shifting the frequency of the scattering light. The scattering spectra thus measured is a molecule’s unique “vibrational fingerprint.”
Fusion energy has the potential to be an effective clean energy source, as its reactions generate incredibly large amounts of energy. Fusion reactors aim to reproduce on Earth what happens in the core of the sun, where very light elements merge and release energy in the process. Engineers can harness this energy to heat water and generate electricity through a steam turbine, but the path to fusion isn’t completely straightforward.
Parachutes have many applications, decelerating everything from skydivers to supersonic-speed scientific payloads. Regardless of what a parachute is slowing down, two things remain constant: the parachute must withstand large amounts of force, and it is crucial to ensuring the safety of whatever it’s carrying. To choose parachute materials that do their jobs effectively, it’s important to fully understand what happens while a parachute is opening and on its way down.
Beckman Institute for Advanced Science and Technology researchers Cutler Phillippe, Francesco Panerai and Laura Villafañe Roca have used computed tomography scans to study the fiber-scale properties of parachute textiles and link them to larger-scale behavior. Their work is published in the American Institute of Aeronautics and Astronautics (AIAA) Journal.
“We know generally how a textile impacts the performance of the parachute,” said Phillippe, a graduate student in the Department of Aerospace Engineering at the University of Illinois Urbana-Champaign. “But we don’t know from an experimental standpoint how that performance is related to the individual fiber motions within the textile as well as the dynamic properties of, for example, a bundle of fibers.”
Active electronics — components that can control electrical signals — usually contain semiconductor devices that receive, store, and process information.
Researchers produced 3D-printed, semiconductor-free logic gates, which perform computations in active electronic devices. As they don’t require semiconductor materials, they represent a step toward 3D printing an entire active electronic device.
Imagine tires that charge a vehicle as it drives, streetlights powered by the rumble of traffic, or skyscrapers that generate electricity as the buildings naturally sway and shudder.
These energy innovations could be possible thanks to researchers at Rensselaer Polytechnic Institute developing environmentally friendly materials that produce electricity when compressed or exposed to vibrations.
In a recent study published in the journal Nature Communications, the team developed a polymer film infused with a special chalcogenide perovskite compound that produces electricity when squeezed or stressed, a phenomenon known as the piezoelectric effect. While other piezoelectric materials currently exist, this is one of the few high-performing ones that does not contain lead, making it an excellent candidate for use in machines, infrastructure as well as bio-medical applications.