Scientists at Argonne National Laboratory have developed a new material that could replace expensive nickel alloys in nuclear reactors.
A research team led by engineers at the University of Virginia School of Engineering and Applied Science is the first to explore how an emerging plant-based material, cellulose nanofibrils, could amplify the benefits of 3D-printed concrete technology.
“The improvements we saw on both printability and mechanical measures suggest that incorporating cellulose nanofibrils in commercial printable materials could lead to more resilient and eco-friendly construction practices sooner rather than later,” said Osman E. Ozbulut, a professor in the Department of Civil and Environmental Engineering.
His team’s findings will be published in the September 2024 issue of Cement and Concrete Composites.
MIT physicists and colleagues report new insights into exotic particles key to a form of magnetism that has attracted growing interest because it originates from ultrathin materials only a few atomic layers thick. The work, which could impact future electronics and more, also establishes a new way to study these particles through a powerful instrument at the National Synchrotron Light Source II at Brookhaven National Laboratory.
An international team of scientists, led by Trinity College Dublin, has devised an innovative imaging method using state-of-the-art microscopes that significantly reduces the time and radiation required. Their work represents a significant breakthrough that will benefit several disciplines, from materials science to medicine, as the method promises to deliver improved imaging for sensitive materials such as biological tissues that are especially vulnerable to damage.
We asked a professional comedian to deliver some jokes written by artificial intelligence on stage. What happened reveals a lot about just how much machines understand the very human sense of humour.
Karen Hobbs was more nervous than usual before this particular gig. A well-known circuit comedian, she’s accustomed to the UK’s often bruising stand-up comedy scene. It’s eclectic, unpredictable and famously short on pity-laughs. Hobbs has tackled some of the most unforgiving rooms in Britain, from major London theatres to the back rooms of rural pubs. She has even triumphed within the dreaded competition circuit, in which a merciless audience votes in a gladiatorial popularity contest for the funniest gags.
But this Thursday night in late June, above the Covent Garden Social Club bar in Central London, Hobbs was about to attempt something totally new. She would take to the stage equipped not with her usual material, but with a stand-up set written for her by the AI platform ChatGPT. Most daunting of all, she would follow three comedians doing their actual, human material.
In 1911, Heike Kamerlingh Onnes discovered the first superconductor, metallic mercury when cooled to a critical temperature of 4.2 Kelvin, where it conducts electricity without resistance. Ever since materials scientists have been on a quest to better understand the phenomenon and whether other elements and materials have higher critical temperatures that could make them useful for practical electricity transport, with the holy grail being ambient temperature.
The ferroelectric material transistor could be used to make NVMe SSDs last a whole lot longer.
This results in differences in the acoustic energy between the LC layers, glass disks, and the surrounding air, inducing an acoustic radiation force acting at the LC layer and glass disk boundary. This effect changes the molecular orientation of the LC layers, altering the transmitted light distribution. By changing the electrodes to which the input voltage is applied, the direction of the molecular orientation and therefore the diffusion directivity can be easily rotated.
The researchers investigated the diffusion characteristics of the device and found that the diffusion angle depends on the input voltage amplitude and is maximized at 16 V. Above this voltage amplitude, the diffused light can become unstable. Additionally, the transmitted light distribution depends on the polarization of incident light.
“Light diffusers that allow control over diffusion directivity can reduce energy consumption and enable users to tune the light distribution to their taste, resulting in better aesthetics Our device marks the first report of an ultrasonically controllable optical diffuser based on LC material, providing users control over diffusion directivity within a small space,” said Prof. Koyama.
Researchers from the University of California, Berkeley have developed cutting-edge nanoscale optical imaging techniques to provide unprecedented insights into the ultrafast carrier dynamics in advanced materials. Two recent studies, published in Advanced Materials (“Transient Nanoscopy of Exciton Dynamics in 2D Transition Metal Dichalcogenides”) and ACS Photonics (“Near-Field Nanoimaging of Phases and Carrier Dynamics in Vanadium Dioxide Nanobeams”), showcase significant progress in understanding the carrier behaviors in two-dimensional and phase-change materials, with implications for next-generation electronic and optoelectronic devices.
The research team, led by Prof. Costas P. Grigoropoulos, Dr. Jingang Li, and graduate student Rundi Yang, employed a novel near-field transient nanoscopy technique to probe the behavior of materials at the nanoscale with both high spatial and temporal resolution. This approach overcomes the limitations of traditional optical methods, allowing researchers to directly visualize and analyze phenomena that were previously difficult to observe.
Schematic of the near-field transient nanoscopy. (Image: Adapted from DOI:10.1002/adma.202311568, CC BY-NC-ND 4.0)
In 2021, the same collaborators developed the technology that acts as an active spin filter made of two successive layers of material, called chiral hybrid organic-inorganic halide perovskites. Chirality describes a molecule’s symmetry, where its mirror image cannot be superimposed on itself. Human hands are the classic example; hold yours out, palms facing away. The right and left hands are arranged as mirrors of one another—you can flip your right hand 180° to match the silhouette, but now the right palm is facing you while the left palm faces away. They’re not the same.
Some molecules, such as DNA, sugar and layers of chiral hybrid organic-halide perovskites, have their atoms arranged in chiral symmetry. The filter works by using a “left-handed” oriented chiral layer to allow electrons with “up” spins to pass, but block electrons with “down” spins, and vice versa. At the time, the scientists claimed the discovery could be used to transform conventional optoelectronics into spintronic devices simply by incorporating the chiral spin filter. The new study did just that.
“We took an LED from the shelf. We removed one electrode and put the spin filter material and another regular electrode. And voila! The light was highly circularly polarized,” said Vardeny.
