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Chemists at UC San Diego have developed a method that for the first time provides scientists the ability to attach chemical probes onto proteins and subsequently remove them in a repeatable cycle. Their achievement, detailed in a paper that appears online this week in the journal Nature Methods, will allow researchers to better understand the biochemistry of naturally formed proteins in order to create better antibiotics, anti-cancer drugs, biofuels, food crops and other natural products. It will also provide scientists with a new laboratory tool they can use to purify and track proteins in living cells. The development was the...

Engineering PbTe on the panoscale making it exceptionally efficient at turning waste heat into electricity © Mercouri KanatzidisResearchers in the US claim to have passed a new milestone in thermoelectrics with a material that converts heat to electricity more efficiently than ever before. The new thermoelectric material, which employs ‘panoscale’ structuring to scatter phonons, has a figure of merit (FoM) some 20% better than previously achieved.Thermoelectrics convert heat to electricity and can, therefore, ‘harvest’ waste heat from the environment. When one end of a thermoelectric material is heated, electrons flow to the cooler side, creating a voltage across the material...

A short exposure, small aperture shot of the TNT formulation burning. The purple colour is down to the potassium perchlorate © WileyIt might seem counterintuitive but one way of making decoy flares for fighter planes better and safer is to make them out of TNT, say European scientists.Decoy flares are pyrotechnic devices shot out of aeroplanes to confuse heat seeking missiles. For the simpler missiles a hot flame will suffice but technology is always improving and advanced missiles now look for the tell tale signatures of water and carbon dioxide to distinguish between a plane and a flare. Of course,...

A pioneering team from IBM in Zurich has published single-molecule images so detailed that the type of atomic bonds between their atoms can be discerned. The same team took the first-ever single-molecule image in 2009 and more recently published images of a molecule shaped like the Olympic rings. The new work opens up the prospect of studying imperfections in the "wonder material" graphene or plotting where electrons go during chemical reactions. The images are published in Science. The team, which included French and Spanish collaborators, used a variant of a technique called atomic force microscopy, or AFM. AFM uses a...

Your eyes aren’t deceiving you — you just watched a metal ball bounce off a sliver of jelly. But you wouldn’t put this jelly in a sherry trifle: it is a sophisticated hydrogel developed by Zhigang Suo, a materials engineer at Harvard University in Cambridge, Massachusetts, and his colleagues1. A hydrogel is a network of polymers that soaks up lots of water to form a jelly-like material. But most shatter easily and don’t stretch far without breaking. Some of the toughest hydrogels are used to make soft contact lenses, and researchers want to make them more robust, for use in...

Enlarge Image Stable Ride. The performance of new lithium-air batteries is nearly unchanged after 100 charge and discharge cycles, which could bode well for their future use in electric vehicles. Credit: (car) Tony Hisgett/ Wikimedia;(graph) Adapted from Z. Peng et al., Science Researchers have long had high hopes for lithium-air batteries, a device that has the potential to store 10 times more energy than the best lithium-ion batteries on the market today. But so far, lithium-air batteries have been unstable, falling apart after a few charges. Now researchers report that they've made the first stable lithium-air batteries. If the...

Foreboding. Animation of changes in ocean acidification over time in the California Current System. The left side shows the depth of aragonite saturation, and the right side shows the surface ocean pH. Courtesy of Nicolas Gruber and Claudine Hauri More Science News Videos Humanity's use of fossil fuels sends 35 billion metric tons of carbon dioxide into the atmosphere every year. That has already begun to change the fundamental chemistry of the world's oceans, steadily making them more acidic. Now, a new high resolution computer model reveals that over the next 4 decades, rising ocean acidity will likely have...

Carbon and nitrogen are well known for their triple bonds, but making stable compounds with a triple bond between two boron atoms hadn’t been achieved despite the computational possibilities. Until now. Holger Braunschweig of the Institute for Inorganic Chemistry at Julius-Maximilians-Universität in Würzburg, Germany, and colleagues found that reacting a bis(N-heterocyclic carbene) stabilised tetrabromodiborane with either two or four equivalents of sodium naphthalenide, a single electron reducing agent, generates a diborene or diboryne compound, which they isolated and characterised. Their analysis confirms a linear, halogen-free compound with a boron-boron triple bond.1 The formation of triple bonds among the lighter main...

Compact device promises to open window on chemical reactions in the lab. The pressurized, cylindrical chamber fits in the palm of Margaret Murnane’s hand. Yet out of one end of the device comes an X-ray beam that packs almost as much punch as the light generated by massive particle accelerators. Murnane and Henry Kapteyn, both physicists at JILA in Boulder, Colorado, a joint institute of the University of Colorado and the US National Institute of Standards and Technology, have reported the first tabletop source of ultra-short, laser-like pulses of low energy, or ‘soft’, X-rays. The light, capable of probing the...

Future prospects for clean, green, renewable energy may hinge upon our ability to mimic and improve upon photosynthesis -- the process by which green plants, algae and some bacteria convert solar energy into electrochemical energy. An artificial version of photosynthesis, for example, could use sunlight to produce liquid fuels from nothing more than carbon dioxide and water. First, however, scientists need a better understanding of how a large complex of proteins, called photosystem II, is able to split water molecules into oxygen, electrons and hydrogen ions (protons). A new road to reaching this understanding has now been opened by an...

A rapid route to synthesise graphene capsules has been developed by researchers in the US and Korea. The capsules can be nano-engineered on demand and show promise in oil absorption. After oil uptake the capsules aggregate on the water surface allowing them to be collected Hollow spheres of graphene or graphene oxide (GO) have previously been made, but usually via complicated routes that involve the assembly of GO sheets onto template particles and then a separate template removal step. Now, a team led by Jiaxing Huang at Northwestern University and HeeDong Jang at the Korea Institute of Geoscience and Mineral...

A team of chemical engineers led by Paul J. Dauenhauer of the University of Massachusetts Amherst has discovered a new, high-yield method of producing the key ingredient used to make plastic bottles from biomass. The process is inexpensive and currently creates the chemical p-xylene with an efficient yield of 75-percent, using most of the biomass feedstock, Dauenhauer says. The research is published in the journal ACS Catalysis. Dauenhauer, an assistant professor of chemical engineering at UMass Amherst, says the new discovery shows that there is an efficient, renewable way to produce a chemical that has immediate and recognizable use for...

Researchers at Cornell University in the US have challenged prevailing fuel cell wisdom by throwing out three standard characteristics of today's mainstream systems to drive down their cost. Héctor Abruña and Abraham Stroock's team changed the fuel and oxidant chemicals used and the cell design that keeps them apart, getting power densities above 0.25 W/cm2. 'What we attain is extraordinary for a device that simple,' Abruña  tells Chemistry World.  'Fuel cells for automotive applications are typically around 1-2W/cm2. It's not that far off.'   The microfluidic fuel cell doesn't need an expensive Nafion membrane to keep the fuel and oxidant separate © Cornell...

The list of remarkable applications for graphene grows ever longer. This time, scientists in the US and Korea have shown that the single-atom thick carbon membrane can be used as a cover slip for an electron microscope to allow atomic-resolution observations of wet chemistry - something that is notoriously tricky to achieve. The graphene cover slip allows researchers to watch liquid chemistry taking place in much greater detail © Image courtesy of Alivisatos, Lee and Zettl research groups, Lawrence Berkeley National Laboratory and KAIST The researchers wanted to investigate how platinum nanocrystals form from solution. 'Seeing the crystals form at...

Squeezing hydrogen at extreme pressures changes it into a mix of honeycombed atoms layered with free-floating molecules — an entirely new state of the element and the first new phase found in decades. If confirmed, the discovery will be only the fourth known phase of hydrogen, the simplest element and one long probed for basic insights into the nature of matter. “I think we have pretty bulletproof evidence that there is a new phase,” says Eugene Gregoryanz of the University of Edinburgh, leader of the team that will report the work in an upcoming Physical Review Letters. Hydrogen’s first three...

Enlarge Image The new graphene. Graphyne may be less famous than graphene, but it could have better electronic properties. Credit: D. Malko et al., Phys. Rev. Lett. (2012) Graphene, a layer of graphite just one atom thick, isn't called a wonder material for nothing. The subject of the 2010 Nobel Prize in physics, it is famed for its superlative mechanical and electronic properties. Yet new computer simulations suggest that the electronic properties of a little-known sister material of graphene—graphyne—may in some ways be better. The simulations show that graphyne's conduction electrons should travel extremely fast—as they do in graphene—but...

Highly sensitive explosives could become safer and greener by exploiting newly characterised ionic polymer structures, say chemists in the US. Such materials could replace explosives based on toxic heavy metals like lead and mercury salts.Sensitive materials are routinely used as primary explosives in detonators to set off larger amounts of less sensitive high explosives in mining or military applications. The challenge is to make them stable enough to be handled safely in the field, but also sensitive enough to detonate reliably, packing as much energetic punch as possible. 'It's a very fine balance,' says Louisa Hope-Weeks of Texas Tech University...

Spectroscopy, a key method of identifying atoms and molecules with light, has been taken to its most fundamental level - a single photon absorbed by a single molecule. In addition to paving the way toward new experiments that observe the interaction between light and matter at its most basic level, the researchers that accomplished the feat suggest that their technique could also work with other photon-emitters, including those under study for quantum communication.Spectroscopy works by finding the frequencies of light that will put an atom or molecule into an excited state - these comprise the chemical's unique absorption and emission...

A metallic lattice of hair-thin pipes is now the lightest solid yet created — less dense than air, scientists revealed. The strategy used to create these intricate structures could lead to revolutionary materials of extraordinary strength and lightness, including ones made of diamond, researchers added. Ultra-lightweight materials such as foams are widely used in thermal insulation and to dampen sounds, vibrations and shocks. They can also serve as scaffolds for battery electrodes and catalytic systems.

A chemist with the Food and Drug Administration pleaded guilty Tuesday to using a confidential drug database to earn nearly $3.8 million by trading the stock of companies with new drug applications.