For tiny fractions of a second, when illuminated by a laser pulse, quartz glass can take on metallic properties. The phenomenon, recently revealed by large-scale computer simulations, frees electrons, allowing quartz to become opaque and conduct electricity. The effect could be used to build logical switches which are much faster than today’s microelectronics.
Polymers come with a range of properties dictated by their chemical composition and geometrical arrangement. Yasuyuki Tezuka and his team at Tokyo Institute of Technology have now applied an approach to synthesize a new type of multicyclic polymer geometry. While mathematicians are interested because these structures have not been realized before, the geometry studies also provide insights for chemists.
A team of scientists from Germany, Canada, and the United States has now developed a promising new measurement method that works without destroying anything yet offers nanoscale resolution. The method, an enhancement of resonant x-ray reflectometry identifies the chemical elements involved and is able to determine both the magnetic order and the electron distribution.
Corrosion, denting, abrasive wear and fatigue often lead to life-limiting bearing and gear failure in harsh conditions. Existing materials, such as hard steels, are prone to corrosion and rust; ceramics are non-conductive, difficult to manufacture and brittle; and superalloys are soft and susceptible to wear and damage. Working with Abbott Ball Company, NASA’s Glenn Research Center has successfully developed a set of methods to create high-performance alternatives to conventional bearing materials.
Thermal fatigue is one of the most important properties in materials used as automobile’s exhaust parts, particularly near the hotter manifold section. When the exhaust gas passes through these parts, they thermally expand or shrink. But they can’t do this freely because of surrounding parts, which leads them to deform or fracture. The solution has long been to add molydenum to the ferritic heat-resistant stainless steels typically used for automobile exhausts. JFE Steel Corp., however, has achieved resistance to thermal fatigue fracture without the use of high-cost molydenum in its JFE-TF1 steel.
Rice Univ. researchers have created a CMOS-compatible, biomimetic color photodetector that directly responds to red, green and blue light in much the same way the human eye does. The new device uses an aluminum grating that can be added to silicon photodetectors with the silicon microchip industry’s mainstay technology, “complementary metal-oxide semiconductor,” or CMOS.
Increasing demand for oil as an energy source and sustained prices of oil on the world market are driving offshore oil producers to seek new finds further offshore. One challenge with deep-water projects is that the emerging oil is much hotter than the surrounding sea, which is near freezing, and needs to be kept warm as it flows through subsea flow elements and pipes to prevent blockage. As a result, flow systems on the seafloor are typically insulated. The Oil Gas & Mining R&D Div. of The Dow Chemical Company has commercialized an innovative new insulation product that can be used in projects that see oil temperatures up to 160 C.
The first direct observations of how facets form and develop on platinum nanocubes point the way towards more sophisticated and effective nanocrystal design and reveal that a nearly 150 year-old scientific law describing crystal growth breaks down at the nanoscale.
New measurements of atomic-scale magnetic behavior in iron-based superconductors by researchers at Oak Ridge National Laboratory and Vanderbilt Univ. are challenging conventional wisdom about superconductivity and magnetism. The study provides experimental evidence that local magnetic fluctuations can influence the performance of iron-based superconductors, which transmit electric current without resistance at relatively high temperatures.
Materials like solid gels and porous foams are used for padding and cushioning, but each has its own advantages and limitations. To overcome limitations, a team from Lawrence Livermore National Laboratory has found a way to design and fabricate, at the microscale, new cushioning materials with a broad range of programmable properties and behaviors that exceed the limitations of the material's composition through 3-D printing.
A team of researchers at Michigan State Univ. has developed a new type of solar concentrator that when placed over a window creates solar energy while allowing people to actually see through the window. It is called a transparent luminescent solar concentrator and can be used on buildings, cell phones and any other device that has a clear surface.
Synthetic diamond’s molecular structure makes it the world’s most versatile supermaterial. With greater hardness than all other materials, its strength is ideal for cutters used in oil and gas drilling, where it enables longer tool lifetime by minimizing wear, reduces downtime and drives down operating costs and carbon footprints.
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.
Thanks to a $1.5 million innovation award from the Gordon and Betty Moore Foundation, Rice Univ. physicist Emilia Morosan is embarking on a five-year quest to cook up a few unique compounds that have never been synthesized or explored. Morosan is no ordinary cook; her pantry includes metals, oxides and sulfides, and her recipes produce superconductors and exotic magnets.
A Univ. of Chicago-led team of researchers has developed a technique to record the quantum mechanical behavior of an individual electron contained within a nanoscale defect in diamond. Their technique uses ultrafast pulses of laser light, both to control the defect’s entire quantum state and observe how that single electron state changes over time.
Graphene may be tough, but those who handle it had better be tender. The environment surrounding the atom-thick carbon material can influence its electronic performance, according to researchers at Rice and Osaka universities who have come up with a simple way to spot contaminants.
Researchers in Europe have succeeded for the first time in growing single-walled carbon nanotubes with only a single, prespecified structure. The nanotubes thereby have identical electronic properties. The decisive trick was producing the carbon nanotube from custom-made organic precursor molecules.
Lawrence Livermore National Laboratory researchers have made a material that is 10 times stronger and stiffer than traditional aerogels of the same density. This ultra-low-density, ultra-high surface area bulk material with an interconnected nanotubular makeup could be used in catalysis, energy storage and conversion, thermal insulation, shock energy absorption and high energy density physics.
Inspired by the discovery of “race track memory” by IBM researchers, scientists at the Univ. of California, Davis, with the support of the Semiconductor Research Corp., are investigating complex oxides that could be used to manipulate magnetic domain walls within the wires of semiconductor memory devices at nanoscale dimensions. This research may lead to devices that displace existing magnetic hard disk drive and solid state RAM solutions.
Injuries, birth defects (such as cleft palates) or surgery to remove a tumor can create gaps in bone that are too large to heal naturally. And when they occur in the head, face or jaw, these bone defects can dramatically alter a person’s appearance. Researchers have developed a “self-fitting” material that expands with warm salt water to precisely fill bone defects, and also acts as a scaffold for new bone growth.
A catalyst made from a foamy form of copper has vastly different electrochemical properties from catalysts made with smooth copper in reactions involving carbon dioxide, a new study shows. The research, by scientists in Brown Univ.’s Center for the Capture and Conversion of CO2, suggests that copper foams could provide a new way of converting excess CO2 into useful industrial chemicals.
A Rice Univ. laboratory has provided proof that foam may be the right stuff to maximize enhanced oil recovery (EOR). In tests, foam pumped into an experimental rig that mimicked the flow paths deep underground proved better at removing oil from formations with low permeability than common techniques involving water, gas, surfactants or combinations of the three.
Using a relatively straightforward technique, a team of NIST researchers has created what may be the most highly enriched silicon currently being produced. The material is more than 99.9999% pure silicon-28, with less than 1 part per million (ppm) of the problematic isotope silicon-29. Many quantum computing schemes require isotopically pure silicon, for example to act as a substrate for qubits.
Zeolites used extensively in industry are promising catalysts that turn biomass into transportation fuels, but the activity and stability of this class of materials is challenging to understand and predict. Employing a combination of methods devised at Pacific Northwest National Laboratory and the Swiss Light Source, scientists were able to determine the distribution of aluminum ions in structural variants of zeolites.
Researchers at the National Physical Laboratory in the U.K. have discovered that the conductivity at the edges of graphene devices is different to the central material. The group used local scanning electrical techniques to examine the local nanoscale electronic properties of epitaxial graphene, in particular the differences between the edges and central parts of graphene Hall bar devices.