Heat drives classical phase transitions, but much stranger things can happen when the temperature drops. If phase transitions occur at the coldest temperatures imaginable, where quantum mechanics reigns, subtle fluctuations can dramatically transform a material. Scientists have explored this frigid landscape of absolute zero to isolate and probe these quantum phase transitions with unprecedented precision.
Using a calculation originally proposed seven years ago to be performed on a petaflop computer,...
Cadmium zinc telluride (CZT) gamma-ray detectors are important new components in spectroscopic...
New supercomputing calculations provide the first evidence that particles predicted by the...
Electronic devices with unprecedented efficiency and data storage may someday run on ferroelectrics—remarkable materials that use built-in electric polarizations to read and write digital information, outperforming the magnets inside most popular data-driven technology. But ferroelectrics must first overcome a few key stumbling blocks, including a curious habit of "forgetting" stored data.
Using a new method to track the electrochemical reactions in a common electric vehicle battery material under operating conditions, scientists at Brookhaven National Laboratory have revealed new insight into why fast charging inhibits this material's performance. The study also provides the first direct experimental evidence to support a particular model of the electrochemical reaction.
Lithium (Li)-ion batteries power almost all of the portable electronic devices that we use every day, including smartphones, cameras, toys and even electric cars. Researchers across the globe are working to find materials that will lead to safe, cheap, long-lasting and powerful Li-ion batteries.
Scientists running the ATLAS experiment at the Large Hadron Collider report the first evidence of a process that can be used to test the mechanism by which the recently discovered Higgs particle imparts mass to other fundamental particles. More rare than the production of the Higgs itself, this process also provides a new stringent test of the Standard Model of particle physics.
Researchers at The Johns Hopkins Univ. report they have deciphered the inner workings of a protein called YiiP that prevents the lethal buildup of zinc inside bacteria. They say understanding YiiP's movements will help in the design of drugs aimed at modifying the behavior of ZnT proteins, eight human proteins that are similar to YiiP, which play important roles in hormone secretion and in signaling between neurons.
Scientists seeking ways to engineer the assembly of tiny particles measuring just billionths of a meter have achieved a new first: the formation of a single layer of nanoparticles on a liquid surface where the properties of the layer can be easily switched. Understanding the assembly of such nanostructured thin films could lead to the design of new kinds of membranes with a variable mechanical response for a wide range of applications.
Sometimes a cell has to die—when it's done with its job or inflicted with injury that could otherwise harm an organism. Conversely, cells that refuse to die when expected can lead to cancer. So scientists interested in fighting cancer have been keenly interested in learning the details of "programmed cell death." They want to understand what happens when this process goes awry and identify new targets for anticancer drugs.
Wouldn’t it be nice to use solar- or wind-generated electricity to turn excess carbon dioxide into fuels and other useful chemicals? The process would store up the intermittent solar or wind energy in a form that could be used when and where it was needed, including in transportation applications, all while getting rid of some greenhouse gas.
Batteries don’t age gracefully. The lithium ions that power portable electronics cause lingering structural damage with each cycle of charge and discharge, making devices from smartphones to tablets tick toward zero faster and faster over time. To stop or slow this steady degradation, scientists must track and tweak the imperfect chemistry of lithium-ion batteries with nanoscale precision.
In recent work at Brookhaven National Laboratory, semiconductor quantum dots (QDs) have been combined with graphene to develop nanoscale photonic devices that can dramatically improve our ability to detect light. The research has demonstrated that the thickness of the organic molecule layer that typically surrounds the QDs is crucial in attaining sufficiently high efficiency of light/energy transfer into the graphene.
Plant scientists at Brookhaven National Laboratory have found that certain enzymes responsible for desaturating fatty acids, the building blocks of oils, can link up to efficiently pass intermediate products from one enzyme to another. The research lead to the development of plants that can accumulate high levels of more healthful polyunsaturated fatty acids, or fatty acids that could be used as raw materials in place of petroleum.
Scientists at Brookhaven National Laboratory are seeking ways to synchronize the magnetic spins in nanoscale devices to build tiny yet more powerful signal-generating or receiving antennas and other electronics. Their latest work shows that stacked nanoscale magnetic vortices separated by a thin layer of copper can be driven to operate in unison, potentially producing a powerful signal that could be put to work in new electronics.
Using principles of energy transfer more commonly applied to designing solar cells, scientists at Brookhaven National Laboratory have developed a new highly sensitive way to detect specific sequences of DNA, the genetic material unique to every living thing. The method is considerably less costly than other DNA assays and has widespread potential for applications in forensics, medical diagnostics and the detection of bioterror agents.
Ever-shrinking electronic devices could get down to atomic dimensions with the help of transition metal oxides. Researchers from Cornell Univ. and Brookhaven National Laboratory have shown how to switch a particular transition metal oxide, a lanthanum nickelate (LaNiO3), from a metal to an insulator by making the material less than a nanometer thick.
Carefully timed pairs of laser pulses at the Linac Coherent Light Source have been used to trigger superconductivity in a promising copper-oxide material and immediately take x-ray snapshots of its atomic and electronic structure as superconductivity emerged. The results of this effort have pinned down a major factor behind the appearance of superconductivity, and it hinges around “stripes” of increase electrical charge.
Scientists at Brookhaven National Laboratory have made the first 3-D observations of how the structure of a lithium-ion battery anode evolves at the nanoscale in a real battery cell as it discharges and recharges. The details of this research, described in a paper published in Angewandte Chemie, could point to new ways to engineer battery materials to increase the capacity and lifetime of rechargeable batteries.
From steel beams to plastic Lego bricks, building blocks come in many materials and all sizes. Today, science has opened the way to manufacturing at the nanoscale with biological materials. Potential applications range from medicine to optoelectronic devices. In a paper published in Soft Matter, scientists announced their discovery of a 2-D crystalline structure assembled from the outer shells of a virus.
Plant growth is orchestrated by a spectrum of signals from hormones within a plant. A major group of plant hormones called cytokinins originate in the roots of plants, and their journey to growth areas on the stem and in leaves stimulates plant development. Though these phytohormones have been identified in the past, the molecular mechanism responsible for their transportation within plants was previously poorly understood. Until now.
Lithium batteries, with their exceptional ability to store power per a given weight, have been a major focus of research to enable use in everything from portable electronics to electric cars. Now researchers at Massachusetts Institute of Technology and Brookhaven National Laboratory have found a whole new avenue for such research: the use of disordered materials, which had generally been considered unsuitable for batteries.
Researchers at the U.S. Department of Energy’s Brookhaven National Laboratory report that, for the first time, a comprehensive set of tools is available for exploring correlations among the morphological, structural, electronic and chemical properties of catalytic materials under working conditions. Two recent studies have used microscopy and spectroscopy to catch custom-built catalysts in action.
New recommendations for using x-rays promise to speed investigations aimed at understanding the structure of biologically important proteins. In their study, the scientists evaluated options to remedy problems affecting data collection. Scientists who use x-ray beams to study protein crystals face a dilemma: The beams provide the best tool for understanding a protein's structure and biological function, but they often damage the crystal.
Quantum dots have potential for applications that make use of their ability to absorb or emit light and/or electric charges. Examples include more vividly colored light-emitting diodes (LEDs), photovoltaic solar cells, nanoscale transistors and biosensors. But because these applications have differing, sometimes opposite, requirements, finding ways to control the dots’ optical and electronic properties is crucial to their success.
By applying pressure to a semiconductor, researchers have been able to transform a semiconductor into a “topological insulator” (TI), an intriguing state of matter in which a material’s interior is insulating but its surfaces or edges are conducting with unique electrical properties. This is the first time that researchers have used pressure to gradually “tune” a material into the TI state.
Hydrogen is a “green” fuel that burns cleanly and can generate electricity via fuel cells. One way to sustainably produce hydrogen is by splitting water molecules using the renewable power of sunlight, but scientists are still learning how to control and optimize this reaction with catalysts. At the National Synchrotron Light Source, a research group has determined key structural information about a potential catalyst.
Sometimes big change comes from small beginnings. That’s especially true in the research of Anatoly Frenkel, a prof. of physics at Yeshiva Univ., who is working to reinvent the way we use and produce energy by unlocking the potential of some of the world’s tiniest structures: nanoparticles.
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