When crude oil is refined to fuels and chemicals, catalysts such as zeolites. are at work making this process happen. Scientists have recently developed a reference parameter for the performance of this important class of catalysts, which can suffer from production hindrances if reaction side products clog pores or block active sites on the catalyst.
Bacteria use threadlike appendages, called pili, to creep along a surface, and some disease-causing microbes extend pili in all directions to move. But until now researchers have been unable to explain why bacteria like these are able to travel in a straight line consistently. A new model developed to describe this movement shows that bacteria do not act as randomly as they appear to when moving.
Saudi Arabian-based petrochemical company SABIC and Cima NanoTech have announced the joint development of a new transparent conductive polycarbonate film. The collaboration leverages both Cima NanoTech’s proprietary SANTE nanoparticle technology and SABIC’s LEXAN film to produce a film that outperforms indium tin oxide by a factor of ten.
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 order to see the true polarization of ferroelectric materials quickly and efficiently, researchers at Argonne National Laboratory have developed a new technique called charge gradient microscopy. Charge gradient microscopy uses the tip of a conventional atomic force microscope to scrape and collect the surface screen charges.
In recent research in Germany, the desorption of oxygen molecules from a silver surface was successfully visualized for the first time using low-energy electron microscopy. The effects account for the shortcomings of conventional models of desorption, which often deliver rates that do not agree with experimentally determined values.
Although the potential uses for graphene seem limitless, there has been no easy way to scale up from microscopic to large-scale applications without introducing defects. Researchers in Chicago and Korea have recently developed a supersonic spray system that produces very small droplets of graphene which disperse evenly, evaporate rapidly, and reduce aggregation tendencies. And, to the researchers’ surprise, it also eliminates defects.
Using a doped-graphene matrix to slow down and then trap atoms of the precious metal osmium, researchers in the U.K. have shown the ability to control and quantify the growth of metal-crystals. When the trapped atoms come into contact with further osmium atoms they bind together, eventually growing into 3-D metal-crystals. They have called this new technique nanocrystallometry.
An international team of researchers from the USA and Japan, including Takao Sasagawa at Tokyo Institute of Technology, have uncovered a two-stage transition in lanthanum-strontium-copper-oxide high-temperature superconductors (LSCOs), leading to the first complex phase diagram of the behavior of LSCOs. This research could improve understanding of high-temperature superconductivity under magnetic fields.
Solar cell technology has advanced rapidly, as hundreds of groups around the world pursue more than two dozen approaches using different materials, technologies and approaches to improve efficiency and reduce costs. Now a team at Massachusetts Institute of Technology has set a new record for the most efficient quantum-dot cells.
Researchers in Japan have developed a new nickel catalyst with a “kabuto-like” structure that was found to catalyze the cross-coupling reaction between carbonyl compounds and readily available phenol derivatives, to form arylketones, which are found in many biologically active compounds. A kabuto is a helmet worn by Japanese samurai.
Soon after graphene’s isolation, early research already showed that lithium batteries with graphene in their electrodes had a greater capacity and lifespan than standard designs. At the Univ. of Manchester, U.K., where graphene was first isolated, researchers are working with more than 30 companies to advance technology in graphene-enabled energy storage, particularly in the area of lithium-ion batteries and supercapacitors.
They are 3-D and yet single-sided: Moebius strips. These twisted objects have only one side and one edge. Using this iconic form, an international team of scientists has succeeded in designing the world’s first “triply” twisted molecule. Because of their peculiar quantum mechanical properties these structures are interesting for applications in molecular electronics and optoelectronics.
Using molecules of DNA like an architectural scaffold, Arizona State Univ. scientists, in collaboration with colleagues at the Univ. of Michigan, have developed a 3-D artificial enzyme cascade that mimics an important biochemical pathway that could prove important for future biomedical and energy applications.
Fancy Erector Set? Nope. The elaborate fractal structure shown at left is many, many times smaller than that and is certainly not child's play. It’s the latest example of a fractal nanotruss—nano because the structures are made up of members that are as thin as 5 nm; truss because they are carefully architected structures that might one day be used in structural engineering materials.
Researchers in Spain have introduced a platform technology based on optical antennas for trapping and controlling light with graphene. Their experiments show that the dramatically squeezed graphene-guided light can be focused and bent, following the fundamental principles of conventional optics. The work opens new opportunities for smaller and faster photonic devices and circuits.
In response to requests from the semiconductor industry, a team of researchers at the Physical Measurement Laboratory has demonstrated that atomic force microscope probe tips made from its near-perfect gallium nitride nanowires are superior in many respects to standard silicon or platinum tips. They also found a way to use the tips as LEDs to illuminate sample regions while scanning.
Scientists at the U.S. Dept. of Energy’s Argonne National Laboratory have discovered a previously unknown phase in a class of superconductors called iron arsenides. This sheds light on a debate over the interactions between atoms and electrons that are responsible for their unusual superconductivity.
Images taken by Rice Univ. scientists show that some diamonds are not forever. The Rice researchers behind a new study that explains the creation of nanodiamonds in treated coal also show that some microscopic diamonds only last seconds before fading back into less-structured forms of carbon under the impact of an electron beam.
Graphene’s promise as a material for new kinds of electronic devices, among other uses, has led researchers around the world to study the material in search of new applications. But one of the biggest limitations to wider use of the strong, lightweight, highly conductive material has been the hurdle of fabrication on an industrial scale.
Crowding has notoriously negative effects at large size scales, blamed for everything from human disease and depression to community resource shortages. But relatively little is known about the influence of crowding at the cellular level. A new JILA study shows that a crowded environment has dramatic effects on individual biomolecules.
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.
Researchers have found that a particular species of quantum dots that weren't commonly thought to blink, do. So what? Well, although the blinks are short, even brief fluctuations can result in efficiency losses that could cause trouble for using quantum dots to generate photons that move information around inside a quantum computer or between nodes of a future high-security internet based on quantum telecommunications.
Melanin—and specifically, the form called eumelanin—is the primary pigment that gives humans the coloring of their skin, hair and eyes. It protects the body from the hazards of ultraviolet and other radiation that can damage cells and lead to skin cancer, but the exact reason why the compound is so effective at blocking such a broad spectrum of sunlight has remained something of a mystery.
An international team of researchers have figured out a new way of storing and releasing hydrogen by making a unique crystal phase of a material containing lithium, boron and the key ingredient, hydrogen. To check how they could get the hydrogen back out of the material, the scientists heated it and found that it released hydrogen easily, quickly and only traces of unwanted by-products.