Inspired by tiny particles that carry cholesterol through the body, Massachusetts Institute of Technology chemical engineers have designed nanoparticles that can deliver snippets of genetic material that turn off disease-causing genes. This approach, known as RNA interference, holds great promise for treating cancer and other diseases. However, delivering enough RNA to treat the diseased tissue has proven difficult.
Materials experts in Ireland have developed a new germanium nanowire-based anode that has the ability to greatly increase the capacity and lifetimes of lithium-ion batteries. The typical lithium-ion battery on the market today is based on graphite, which has a relatively low capacity for energy storage. Restructuring the germanium replacement material into nanowires produces a stable, porous battery material.
A team of physicists have used statistical mechanics and mathematical modeling to shed light on something known as epigenetic memory, which allows an organism to create a biological memory of some variable condition, such as quality of nutrition or temperature. The model highlights the "engineering" challenge a cell must constantly face during molecular recognition.
U.S. Army-sponsored researchers have discovered a process for simultaneously storing and dissipating energy within structures that could lead to design rules for new types of active, reconfigurable materials. The study method was derived from an examination of how a species of South American fire ant collectively entangle themselves to form an active structure capable of changing state from a liquid to a solid when subject to applied loads.
Topological insulators have been of great interest to physicists in recent years because of unusual properties that may provide insights into quantum physics. But most analysis of such materials has had to rely on highly simplified models. Now, a team of researchers at Massachusetts Institute of Technology has performed a more detailed analysis that hints at the existence of six new kinds of topological insulators.
Lead-free BaTiO3 and KNbO3 ferroelectrics have been known and studied for more than 60 years. However, recent scanning x-ray diffraction studies at Argonne National Laboratory have shown new low-symmetry intermediate phases in these materials that lend a thermotropic character to otherwise well-known phase transitions. The findings show that these transitions in ferroelectrics are closely coupled to the underlying domain microstructure.
An international team of researchers from France and the United States have devised an entirely new way to synthesize graphene ribbons with defined, regular edges, allowing electrons to flow freely through the material. Demonstrating this phenomenon at room temperature, the material was shown to permit electron flow up to 200 times faster than through silicon.
Texas Advanced Computing Center recently reported the results of several massive numerical simulations charting the forces of the universe in its first hundreds of millions of years. The study, which used some of the world's most powerful supercomputers, has refined our understanding of how the first galaxies formed, and, in particular, how metals in the stellar nurseries influenced the characteristics of the stars in the first galaxies.
Working on the cutting edge of a newly emerging area of solar-cell research, Univ. of California, Los Angeles engineers have invented a new process for manufacturing highly efficient photovoltaic materials that shows promise for low-cost industrial production. The new process uses so-called perovskite materials, which in the past few years have significantly advanced scientists' efforts to create the next generation of solar cells.
We all learn in high school science about the dual nature of light—that it exists as both waves and quantum particles called photons. It’s this duality of light that enables the coherent transport of photons in lasers. Sound at the atomic-scale has the same dual nature, existing as both waves and quasi-particles known as phonons. Does this duality allow for phonon-based lasers?
Using electrons more like photons could provide the foundation for a new type of electronic device that would capitalize on the ability of graphene to carry electrons with almost no resistance even at room temperature—a property known as ballistic transport. Research reported that electrical resistance in nanoribbons of epitaxial graphene changes in discrete steps following quantum mechanical principles.
Researchers at Tyndall National Institute in Ireland have produced the first ever atom-by-atom simulation of nanoscale film growth by atomic layer deposition (ALD), a thin-film technology used in the production of silicon chips. The accomplishment required the acquisition of the complete set of hundreds of ALD reactions at the quantum mechanical level.
Individual silver nanoparticles in solutions typically grow through single atom attachment, but when they reach a certain size they can link with other particles, according to a team which includes scientists at Pacific Northwest National Laboratory. This seemingly simple result has shifted a long-held scientific paradigm that did not consider kinetic models when explaining how nanoparticle ensembles formed.
Research from a team led by North Carolina State Univ. is opening the door to smarter sensors by integrating the smart material vanadium dioxide onto a silicon chip and using lasers to make the material magnetic. The advance paves the way for multifunctional spintronic smart sensors for use in military applications and next-generation spintronic devices.
Look out, super glue and paint thinner. Thanks to new dynamic materials developed at the Univ. of Illinois, removable paint and self-healing plastics soon could be household products. Other self-healing material systems have focused on solid, strong materials, but this new study uses softer elastic materials made of polyurea, one of the most widely used classes of polymers in consumer goods such as paints, coatings, elastics and plastics.
New research shows that a remarkable defect in synthetic diamond produced by chemical vapor deposition allows researchers to measure, witness, and potentially manipulate electrons in a manner that could lead to new “quantum technology” for information processing.
Trying to find new materials, to improve the performance of anything from microchips to car bodies, has always been a process of trial and error. Massachusetts Institute of Technology materials scientist Gerbrand Ceder likens it to setting out from Boston for California, with neither a map nor a navigation system—and on foot.
In a world’s first, researchers at the National Institute of Materials Science in Japan have succeeded in controlling the length of a one-dimensional, or supramolecular, assembly of molecules. Their method involves molecular self-organization, which until now has not been practical for polymer synthesis because of a lack of knowledge about the interplay of organizational pathways.
Scientists have used a particle physics theory to describe the behavior of particle-like entities, referred to as excitons, in two layers of graphene. The use of equations typically employed in high-energy physics has prompted the authors to suggest a design for an experimental device relying on a magnetically tunable optical filter that could verify their predictions.
Perfect sheets of diamond a few atoms thick appear to be possible even without the big squeeze that makes natural gems. Scientists have speculated about it and a few laboratories have even seen signs of what they call diamane, an extremely thin film of diamond that has all of diamond’s superior semiconducting and thermal properties.
A group of Washington State Univ. researchers has developed a chewing gum-like battery material that could dramatically improve the safety of lithium-ion batteries. High-performance lithium batteries are popular in everything from computers to airplanes because they are able to store a large amount of energy compared to other batteries. Their biggest potential risk, however, comes from the electrolyte in the battery.
Infrared sensors can be employed in a wide range of applications, such as driver assistance systems for vehicles or thermography for buildings. However, IR detectors need to be permanently cooled, resulting in cameras that are large, heavy and energy-intensive. Researchers are now developing IR sensors for the far-infrared region that can operate at room temperature and a new prototype camera is providing a test bed for development.
Scientists at Argonne National Laboratory attacked a tangled problem by developing a new technique to grow tiny “hairy” materials that assemble themselves at the microscale. The key ingredient is epoxy, which is added to a mixture of hardener and solvent inside an electric cell. Then the scientists run an alternating current through the cell and watch long, twisting fibers spring up. It looks like the way Chia pets grow in commercials.
Only a few elements in the periodic table are inherently magnetic, but scientists have recently discovered that gold, silver, platinum, palladium and other transition metals demonstrate magnetic behavior when formed into nanometer-scale structures. Scientists at the RIKEN Center for Emergent Matter Science have now shown that this nanoscale magnetism in thin films of platinum can be controlled using an externally applied electric field.
A team of researchers at the Univ. of Delaware has developed a highly selective catalyst capable of electrochemically converting carbon dioxide to carbon monoxide with 92% efficiency. The carbon monoxide then can be used to develop useful chemicals. The exceptionally high activity of the new electrocatalyst is due to its extremely large and highly curved internal surface.