Univ. of Washington researchers have developed what they believe is the thinnest-possible semiconductor, a new class of nanoscale materials made in sheets only three atoms thick. They have demonstrated that two of these single-layer semiconductor materials can be connected in an atomically seamless fashion known as a heterojunction. This result could be the basis for next-generation flexible and transparent computing.
Scientists in The Netherlands have demonstrated that they can detect extremely small changes in position and forces on very small drums of graphene. Graphene drums have great potential to be used as sensors in devices such as mobile phones. Using their unique mechanical properties, these drums could also act as memory chips in a quantum computer.
A new argument has just been added to the growing case for graphene being bumped off its pedestal as the next big thing in the high-tech world by the 2-D semiconductors known as MX2 materials. An international collaboration of researchers led by Lawrence Berkeley National Laboratory has reported the first experimental observation of ultrafast charge transfer in photo-excited MX2 materials.
By combining plasmonics and optical microresonators, researchers at the Univ. of Illinois at Urbana-Champaign have created a new optical amplifier (or laser) design, paving the way for power-on-a-chip applications. The speed of currently available semiconductor electronics is limited to about 10 GHz due to heat generation and interconnects delay time issues.
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.
Bridges become an infrastructure problem as they get older, as de-icing salt and carbon dioxide gradually destroy the reinforced concrete. A new robot called C2D2 (Climbing Corrosion Detecting Device) is now in use in Switzerland and can check the condition of these structures, even in places that people cannot reach.
Univ. of Illinois engineers are bringing a touch of color to glucose monitoring. The researchers developed a new continuous glucose monitoring material that changes color as glucose levels fluctuate, and the wavelength shift is so precise that doctors and patients may be able to use it for automatic insulin dosing—something now possible using current point measurements like test strips.
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.
A mechanical engineering student at EPFL in Switzerland wanted to understand the reason behind the formation of a “foam volcano” after tapping the neck of a bottle of beer. He studied the phenomenon with a high-speed camera and compared it to the outcome of applying the same action to sparkling water. His work offers insights into the behavior of cavitation nuclei.
A research team investigating an important cofactor in photosynthesis, a manganese-calcium complex which uses solar energy to split water into molecular oxygen, have determined the exact structure of this complex at a crucial stage in the chemical reaction. The new insights into how molecular oxygen is formed at this metal complex may provide a blueprint for synthetic systems that could store sunlight energy in chemical energy carriers.
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.
Scientists have, for the first time, characterized so-called quantum vortices that swirl within tiny droplets of liquid helium. The research, led by scientists at Lawrence Berkeley National Laboratory, the Univ. of Southern California and SLAC National Accelerator Laboratory, confirms that helium nanodroplets are in fact the smallest possible superfluidic objects and opens new avenues for studying quantum rotation.
Trying to understand the chemistry that turns plant material into the same energy-rich gasoline and diesel we put in our vehicles, researchers have discovered that water in the conversion process helps form an impurity which, in turn, slows down key chemical reactions. The study, which was reported online at the Journal of the American Chemical Society, can help improve processes that produce biofuels from plants.
Research published in ACS Nano identifies a new type of sensor that could monitor body movement and advance the future of global health care. Although body motion sensors already exist in different forms, they have not been widely used due to their complexity and cost of production.
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.
The invention of fiber optics revolutionized the way we share information, allowing us to transmit data at volumes and speeds we’d only previously dreamed of. Now, electrical engineering researchers at the Univ. of Alberta are breaking another barrier, designing nano-optical cables small enough to replace the copper wiring on computer chips.
Anyone who has ever had a glass of fizzy soda knows that bubbles can throw tiny particles into the air. But in a finding with wide industrial applications, Princeton Univ. researchers have demonstrated that the bursting bubbles push some particles down into the liquid as well.
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.