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A team of researchers from the U.S. Department of Energy’s Argonne National Laboratory, the University of Chicago, and the University of Wisconsin-Milwaukee has devised a pathway for the mass manufacture of sensors that can simultaneously detect lead, mercury, and E. coli bacteria in flowing tap water. At the core of these sensors lies a one-nanometer-thick layer of carbon and oxygen atoms, which is coated on a silicon substrate.
Using cutting-edge tools, scientists from the Center for Functional Nanomaterials, a user facility at the U.S. Department of Energy’s Brookhaven National Laboratory, and the Institute of Experimental Physics at the University of Warsaw have created a new layered structure with two-dimensional (2D) materials that exhibits a unique transfer of energy and charge. The team was able to get a more detailed picture of how long-distance energy transfer works in transition metal dichalcogenides – a class of materials structured like sandwiches with atomically thin layers.
Researchers from Northwestern University, the Houston Methodist Research Institute, the University of Texas MD Anderson Cancer Center, New York University Langone School of Medicine, and the University of Texas at Austin have developed a novel single-cell nanopore genetic sequencing tool that accelerates sequencing analysis of same-cell genotypes and phenotypes in tumors. Single-cell nanopore RNA sequencing is a new type of genetic sequencing technique that can directly measure the full length of RNAs (instead of short strands of RNAs, which are commonly sequenced by current techniques).
Researchers at the University of Illinois Urbana-Champaign and the University of Lille in France have identified a novel pathway to stabilize nanoscale precipitates in alloys. "In the last two decades, researchers have realized that having nanoscale inclusions in the structure can actually be very beneficial to the material," said Pascal Bellon, one of the scientists involved in this study. "The challenge is that spontaneously, these small particles want to grow bigger." The researchers found that when irradiated, the nanoscale precipitates would form, as expected, but instead of continuing to grow, they would reach a certain size and stop.
Scientists from Rice University, George Mason University, Johns Hopkins University, and Princeton University have discovered that tiny gold "seed" particles, a key ingredient in one of the most common nanoparticle recipes, are the same as gold buckyballs – 32-atom spherical molecules that are cousins of 60-carbon-atom molecules called buckyballs. Confirming that the widely used seeds were 32-gold-atom molecules rather than nanoparticles took years of effort, including state-of-the-art imaging and detailed theoretical analyses by the scientists.
Researchers from North Carolina State University, Iowa State University, and the University of British Columbia have developed a technique that uses a molecule-thin protective layer to control how the heat of a flame interacts with a material. "Our technique … employs a nanoscale thin film over a targeted material,” said Martin Thuo, one of the scientists involved in this study. “The thin film changes in response to the heat of the fire and regulates the amount of oxygen that can access the material. That means we can control the rate at which the material heats up." This work was performed in part at the Analytical Instrumentation Facility (AIF) at North Carolina State University, which is a member of the North Carolina Research Triangle Nanotechnology Network (RTNN), a site in the National Nanotechnology Coordinated Infrastructure (NNCI).
Researchers at the University of Central Florida have developed new ways to produce energy and materials from methane, a greenhouse gas. The scientists invented a method to produce hydrogen from methane without releasing contaminants, such as higher polyaromatic compounds, carbon dioxide. or carbon monoxide. By using visible light and defect-engineered boron-rich photocatalysts, the innovation highlights a new functionality of nanomaterials for visible light-assisted capture and conversion of methane. Defect engineering refers to creating irregularly structured materials.
Researchers at Columbia University, the Technical University of Denmark, Aarhus University in Denmark, Université Paris-Saclay, and the National Institute for Materials Science in Tsukuba, Japan, have developed a simple new fabrication technique that may help physicists probe the fundamental properties of twisted layers of graphene and other 2D materials in a more systematic and reproducible way. They used long "ribbons" of graphene, rather than square flakes, to create devices that offer a new level of predictability and control over both twist angle and strain. The researchers showed that with just a little push from the tip of an atomic force microscope, they can bend a graphene ribbon into a stable arc that can then be placed flat on top of a second, uncurved, graphene layer.
Researchers at the University of Chicago have found that a sheet of glass crystal just a few atoms thick could trap and carry light. This discovery demonstrates what are essentially 2D photonic circuits. Photonic circuits already exist, but they are larger and three-dimensional, and particles of light, or photons, travel enclosed inside the waveguides used in these circuits. (Waveguides act like the wires that are used to carry electrical signals, but they carry photons instead.) With this system, the glass crystal is thinner than a photon – so, part of a photon actually sticks out of the crystal, as it travels. This work made use of the fabrication facilities of the Pritzker Nanofabrication Facility at the University of Chicago, which receives support from SHyNE Resource, a node of the National Nanotechnology Coordinated Infrastructure.
In rooms where smoking has taken place regularly, tobacco's imprint lingers on indoor surfaces, even long after regular smoking has stopped. The leftover residues, known as thirdhand smoke, can be a long-term source of indoor pollutants. Now, researchers from the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab), the University of California Berkeley, the University of California Riverside, and San Diego State University, have examined smoke-contaminated aged carpets and new carpets exposed to fresh smoke in the lab and found that carpets can be an important reservoir and source of contaminants from thirdhand smoke. The work was carried out at Berkeley Lab’s Air Quality Testing Laboratory and the Molecular Foundry, a user facility at Berkeley Lab.
