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University of North Dakota scientist Mark Hoffmann's version of Star Search goes a long way -- a very long way -- out into the universe. Hoffmann, a computational chemist, and his colleagues Tryve Helgaker, a well-known Norwegian scientist, and co-authors E.I. Tellgren and K. Lange, also working in Norway, have discovered a molecular-level interaction that science had puzzled over for decades but had never seen. That discovery, it turns out, may redefine how science views chemical compound formation. It also answers questions about what goes on in places like white dwarfs, the super dense cores of stars nearing the end...

US scientists have developed a way to solve crystal structures that combines powerful computational methods with data from experiments or databases – but that does not require much human input. Previous computational methods to predict structures rarely use experimental data, take a long time and are limited to compounds with small unit cells. They also give structures that generally have lower symmetry than those which have been experimentally determined, suggesting that the answers may not be quite right.‘One of the dirty little secrets that people don’t generally talk about is that, with a lot of these methods, you always...

Calling chemistry ‘molecular architecture’ is even more apt than it might seem. There was a time when architectural engineering was largely about getting buildings to stay up: to withstand the stresses and forces that act on them. But today’s architecture is responsive, mutable, adaptive and dynamic. Likewise, chemistry could appear in its first flush to be about making bonds that will last, but today’s chemistry is just as concerned with breaking as it is with making. The dynamic role of weak hydrogen bonding, for example, was illustrated with the discovery of DNA’s structure: to template replication and transcription, the molecule...

Enlarge Image Cutting edge. After it was divided with a scalpel, a new polymer was able to heal itself, restoring most of its mechanical and electrical properties in 15 seconds. Credit: Benjamin Tee and Chao Wang Human skin is a special material: It needs to be flexible, so that it doesn't crack every time a user clenches his fist. It needs to be sensitive to stimuli like touch and pressure—which are measured as electrical signals, so it needs to conduct electricity. Crucially, if it's to survive the wear and tear it's put through every day, it needs to be...

Most probiotic bacteria that are added to foods, such as yoghurt, to aid the digestive system are not reaching their intended target in the intestine. Instead, the majority are being destroyed in the stomach before they can do any good. Now, UK scientists have come up with a coating to overcome this problem.1Probiotic bacteria are added to food such as yoghurt drinks to aid the digestive system. © Shutterstock Probiotics are bacteria that naturally live in the small and large intestine. They provide health benefits by producing nutrients, compete with pathogenic bacteria for binding sites and stimulate the immune system....

An inkjet printer has been repurposed to create a huge library of potential catalysts. To make the technology work with inorganic reagents that have different chemistries, a collaboration between chemists at the University of California, Santa Barbara, US, and Zhejiang University in China, has created special 'inks' made of colloidal nanoparticles of different metal precursors and polymers that direct the formation of the resulting nanoparticle structures.Different nanoparticle inks can then be loaded into seperate ink containers and combined in precise amounts, resulting in up to 1 million new formulations an hour, containing up to eight different components. That resulting...

French researchers have made the longest molecular machines that can be shrunk on demand in a collective motion that emulate muscle fibres.1Nicolas Giuseppone from the University of Strasbourg and his teammates linked together strings of around 3000 macromolecular daisy-chain rotaxane monomers that contract under basic conditions. The resulting polymer went from 15.8 µm to 9.4 µm, movement in the range of that produced by sarcomere proteins, the basic building blocks of muscle. That amplifies a single daisy-chain rotaxane’s contraction by nearly four orders of magnitude, Giuseppone tells Chemistry World. ‘This is a result long expected by the community, but it...

The macrocycle can trap polycyclic aromatic hydrocarbons US chemists have designed a novel macrocyclic molecule that may be able to scavenge an important class of toxic hydrocarbons from the environment. The rectangular cyclophane can trap a wide range of polycyclic aromatic hydrocarbons – PAHs – several of which are carcinogenic. The molecule, dubbed ExBox, was shown to remove PAHs from a sample of crude oil. Additionally, the crystallised complex of ExBox and particular PAHs contain stacked aromatic rings which could have novel or unusual electronic properties.The team, at Northwestern University in Illinois, constructed the cyclophane by taking an extended...

The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Chemistry for 2012 to Robert J. Lefkowitz, Howard Hughes Medical Institute and Duke University Medical Center, Durham, NC, USA and Brian K. Kobilka, Stanford University School of Medicine, Stanford, CA, USA "for studies of G-protein–coupled receptors"

<p>Last month’s arrest of a chemist, who worked in a Massachusetts Department of Public Health state laboratory, for allegedly falsifying evidence used in criminal cases is prompting calls for major forensic science reform in the US.</p> <p>Over her nine year career at the William A Hinton State Lab in Jamaica Plain the defendant, Annie Dookhan, tested about 60,000 samples involved in roughly 34,000 criminal cases. More than 1140 defendants have been incarcerated as a result of Dookhan’s work and those cases are now in doubt, says Terrel Harris, spokesperson for the Massachusetts Executive Office of Public Safety and Security.</p>

Dissolvable electronic materials could be used in medical implants and environmentally friendly gadgets. A team of researchers has designed flexible electronic components that can dissolve inside the body, and in water. The components could be used to make smart devices that disintegrate once they are no longer useful, helping to alleviate electronic waste and enabling the development of medical implants that don’t need to be surgically removed. So far, the team has designed an imaging system that monitors tissue from within a mouse, a thermal patch that prevents infection after a surgical site is closed up, solar cells and strain...

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...