Researchers created graphene oxide nanosheets from readily available carbon fibers.
Researchers develop a new method for producing graphene oxide from carbon fibers, offering a sustainable alternative to graphite mining.
Category: materials – Page 16
Supersolids are strange materials that behave like both a solid and a fluid due to quantum effects – and now researchers have created an intriguing new type of supersolid from laser light.
Ever set off too many of the bitter taste receptors on your tongue? You probably spat out whatever it was in your mouth, and that’s our best guess for why we even have them: to stop us from ingesting things that might be harmful.
Our skin cells have the same receptors, which serve a similar purpose on a cellular level: to detect bitter substances. New research led by Okayama University of Science biologists builds on our knowledge of the type-2 taste receptors (TAS2Rs) found in the skin’s keratinocytes, finding their role is also to keep potentially harmful materials from sticking around and causing damage.
Once thought to be confined to the tongue, TAS2Rs are actually spread much further throughout the body. They line your colon, your stomach, and your upper airways.
Materials are known to interact with electromagnetic fields in different ways, which reflect their structures and underlying properties. The Lyddane-Sachs-Teller relation is a physics construct that describes the relationship between a material’s static and dynamic dielectric constant (i.e., values indicating a system’s behavior in the presence or absence of an external electric field, respectively) and the vibrational modes of the material’s crystal lattice (i.e., resonance frequencies).
This construct, first introduced by physicists Lyddanne, Sachs and Teller in 1941, has since been widely used to conduct solid-state physics research and materials science studies. Ultimately, it has helped better explain and delineate the properties of various materials, which were then used to create new electronic devices.
Researchers at Lund University recently extended the Lyddane-Sachs-Teller relation to magnetism, showing that a similar relation links a material’s static permeability (i.e., its non-oscillatory response to a magnetic field) to the frequencies at which it exhibits a magnetic resonance. Their paper, published in Physical Review Letters, opens new exciting possibilities for the study of magnetic materials.
Researchers have typically assumed that both LLVPs are similar to each other in nature, e.g. chemical composition and age, because seismic waves travel through them in similar ways. But a new study, co-authored by Dr. Paula Koelemeijer (Department of Earth Sciences, University of Oxford), has challenged this view by modelling the formation of the LLVPs through time.
By combining a model of mantle convection, including a reconstruction of how tectonic plates have moved over the Earth’s surface over the last billion years, the study has been able to show that the African LLVP consists of older and better mixed material than the Pacific LLVP, which contains 50% more and younger subducted oceanic crust (and therefore is more different to the surrounding mantle). The resulting differences in density could also explain why the African LLVP is more diffuse and taller than its Pacific counterpart.
Researchers have discovered that incipient ferroelectricity can revolutionize computer memory, enabling ultra-low power devices.
These unique transistors shift behavior based on temperature, making them suitable for both traditional memory and neuromorphic computing, which mimics the brain’s energy efficiency. The use of strontium titanate thin films reveals unexpected ferroelectric-like properties, hinting at new possibilities in advanced electronics.
Superconductivity is an intriguing property observed in some materials, which entails the ability to conduct electric current combined with an electrical resistance of zero at low temperatures. Physicists have observed this property in various solid materials with different characteristics and atomic thicknesses.
A team of researchers at Nanjing University in China recently carried out a study aimed at further exploring the behavior of niobium diselenide (NbSe₂), a layered material that has been found to be a superconductor when it is atomically thin. Their paper, published in Physical Review Letters, unveils resilient superconducting fluctuations in atomically thin NbSe₂, which could play a part in the anomalous metallic state previously observed in this material.
“Our study was inspired by a long-standing puzzle in condensed matter physics, which can be summarized by the question: can metals truly exist in two dimensions as the ground state?” Xiaoxiang Xi, senior author of the paper, told Phys.org. “While we understand the behavior of everyday metals and insulators, ultrathin materials—like sheets just one atom thick—challenge these conventional rules.”
Second, the crucial point is that there is no such thing as “natural resources.” That term implies that resources are already existing quantities that we merely have to pick up. In reality, resources are services that we derive by combining raw materials with knowledge and purpose. As Simon put it:
“…natural phenomena such as copper and oil and land were not resources until humans discovered their uses and found out how to extract and process them, and thereby made their services available to us. Hence resources are, in the most meaningful sense, created, and when this happens their availability increases and continues to increases as long as our knowledge of how to obtain them increases faster than our use of them, which is the history of all natural resources.” (p.75 footnote)
When people talk about what percentage of world resources are used up by the population of the USA they fail to recognize the creation of resources. Humans have become ever better at creating resources. Consider farmland. Farmland is not a natural resource. It requires tools and work by humans to produce what we want. And metals: Before we knew how to extract and use them, the vast amounts of tin, lead, iron, aluminum and other metals were not resources, they were merely materials. Neither oil nor gas nor petroleum were considered resources until humans saw how to use them to produce value and added our knowledge to turn minerals into resources.
“This discovery not only sets a new standard for superelastic materials but also introduces new principles for material design, which will undoubtedly inspire further breakthroughs in materials science,” Xu said.
The newly developed Ti-Al-Cr shape-memory alloy is part of the titanium alloy family, known for being lightweight, strong, biocompatible, and resistant to corrosion. What makes this alloy particularly exciting is its ability to maintain superelasticity across a wide temperature range, making it highly suitable for extreme environments such as deep space and deep-sea exploration.
In space missions, materials must endure harsh conditions while remaining functional. Current superelastic tires made from nickel-titanium (Ni-Ti) for upcoming Moon and Mars missions have limited temperature ranges, which could affect their durability.