Photonics: Although iron pyrite, otherwise known as iron sulfide or fool's gold, was tossed aside by miners more than a century ago, it may prove to be worth its weight in gold as a thin-film solar cell material. Researchers at Oregon State University have found that iron pyrite, which contains two of the most abundant elements on Earth, is an excellent absorber of solar energy and can be made into extremely thin layers. Unfortunately, the substantial heat required to create solar cells causes the pyrite to decompose. So the researchers tried an inverse design approach. "We identified the failure mechanism of pyrite, formulated a few design rules that preserved the favorable aspects of pyrite, and identified [iron silicon sulfide] and [iron germanium sulfide] as new absorber candidates," said Douglas Keszler, coauthor of a paper published in Advanced Energy Materials. But much more work remains to be done. It could take at least 10 more years to fine-tune a marketable alternative to traditional solar cell materials.
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BBC: In the future oil spills and waste water could be cleaned up by combining the properties of magnetism and soap. Julian Eastoe of the University of Bristol and colleagues added iron atoms to soap molecules and found that the atoms clumped together into nanoparticles that responded to a magnetic field. The soap and any materials it picks up, can then be removed from water by applying a magnetic field.
New York Times: The chrome look is making a comeback for automobiles, writes Tudor Van Hampton for the New York Times. However, rather than actual chrome, which is expensive and heavy, manufacturers are using materials that mimic chrome. One such material has been produced by Hamlin Jennings, a cement scientist at MIT who has developed a process to coat aluminum with a thin layer of glass. The glass chemically fuses to the metal, producing the look of polished chrome and protecting the surface from scratches and oxidation. The process will probably be used mainly in luxury vehicles for trim around windows and headlights. For most purposes, a good-quality shiny plastic is just as effective and much less expensive.
BBC: At the extreme pressures and temperatures of Earth’s interior, iron oxide changes from insulator to conductor while still retaining its structure, according to a team at the Carnegie Institution of Washington.The researchers subjected the material to conditions found at the boundary between Earth’s two innermost layers and found that at a pressure of 690 000 atmospheres and a temperature of 1650 °C, the iron oxide metallizes without any change in structure. Moreover, their simulations show that its electrons behave differently from those of other metals. Because much of Earth’s mantle is composed of iron oxide and magnesium, the metallization of the iron oxide means it could electrically link the core and the mantle, which would affect the way the magnetic field propagates to Earth’s surface and beyond. The team's results are to be published in Physical Review Letters.
BBC: Names have been submitted for two chemical elements that were recently added to the periodic table. Both elements are the product of collaborative work between scientists at the Joint Institute for Nuclear Research in Dubna, Russia, and Lawrence Livermore National Laboratory in California. More than a decade ago, the scientists created element 114 by smashing calcium ions into the element plutonium, and element 116 by smashing calcium into curium. The proposed names for the new elements are, respectively, flerovium, in honor of physicist Georgy Flerov, and livermorium. The International Union of Pure and Applied Chemistry, which accredited the two elements in June, is allowing five months for the public to comment on the names before officially endorsing them.
Talking Points Memo: Researchers at HRL Laboratories, Caltech, and the University of California, Irvine have created the world’s lightest material—ultralight metallic microlattice. The researchers poured a liquid material into the microlattice pattern and hardened it by exposing it to UV light, writes Carl Franzen for Talking Points Memo. Electroless nickel—an alloy of nickel and phosphorous—was then poured onto the pattern very precisely, forming a 100-nanometer-thin uniform coating. The resulting material is 99.99% air and has a density of only 0.9 mg/cc. Much lighter than Styrofoam, it floats to the ground like a feather when dropped, according to William Carter of HRL, one of the authors of a recent Science paper on the subject. However, it is the structure itself that is important, not the material it is made from. According to Carter, his team can “make the same structure out of many different materials,” including polymers and ceramics. Developed for the Defense Advanced Research Projects Agency, such ultralight cellular materials could be used in thermal insulation, batteries, and acoustics.
New Scientist: Researchers at the University of Texas at Dallas are working on a hydrogen fuel cell that uses aluminum as a catalyst. Although fuel cells are a potentially highly efficient power source for cars, their cost has proven prohibitive because they require expensive noble metals such as platinum for a catalyst. Now Irinder Chopra and coworkers have found that if aluminum is treated with a tiny bit of titanium and exposed to molecular hydrogen at 90 kelvin, the H2 will break up and bind to the metal. When the metal is heated the hydrogen is released and forms H2 again. The team’s results were published in Nature Materials.
Guardian: Thousands of books were lost, burned, or scattered during the upheaval of Europe's Dark Ages. Among those missing books were treatises by some of the earliest mathematicians, such as Archimedes. But some of the material is now being rediscovered with the use of modern technology.
Centuries ago parchment was expensive, so scribes would frequently reuse pieces by scratching out the old text and replacing it with new. It was discovered years ago that a 13th century Byzantine prayer book was actually composed of several earlier, overwritten manuscripts—one of which contained several treatises by Archimedes that were copied in 10th century Constantinople. As Physics Today reported 10 years ago, by illuminating the manuscript with specific wavelengths of light and by applying intensive data analysis to the scattered images, the original wording can be recovered.
Besides Archimedes’ treatises, the prayer book also contained speeches by the classical Athenian orator Hyperides and a lost commentary on Aristotle's Categories.
The so-called Archimedes Palimpsest is on display through 1 January 2012 at the Walters Art Museum in Baltimore, Maryland, and next week Cambridge University Press is publishing a two-volume book on the subject.
BBC: A team of researchers at the Joseph Fourier University in Grenoble, France, is working on a biofuel cell that uses glucose and oxygen at concentrations found in the human body to generate electricity. Serge Cosnier and colleagues estimate that within a decade or two, biofuel cells may be used to power a range of medical implants, from sensors and drug delivery devices to entire artificial organs, writes David Cohen for the BBC. The fundamental limitation on such devices has always been the battery needed to keep them running; whereas batteries need to be continuously replaced over a patient’s lifetime, biofuel cells could keep working indefinitely. A biofuel cell is made of two special electrodes. One removes electrons from glucose, and the other donates electrons to oxygen and hydrogen molecules, producing water. Although biofuel cells were first proposed in the 1970s, recent breakthroughs in the understanding of enzymes have resulted in several groups around the world working on such devices.
Nature: Rather than try to compete with the giant petrochemical companies by producing alternative fuels, some synthetic biology firms have branched out to also produce specialist chemicals used in a number of products, such as cat food, face cream, and tires. Such bio-derived products make up just 1–2% of the overall chemicals market, but that could amount to about $1 billion next year. A California-based company, Amyris, for example, is working with French tire manufacturer Michelin to produce isoprene, the chemical building block used to make synthetic rubber. Another California-based company, Solazyme, is working with UK-based Unilever, which owns the Dove and Vaseline brands, to make cosmetic ingredients. Conventional chemical companies such as Dow and DuPont have become interested because bio-derived versions of their products can be marketed as “green” and because the cost of oil is rising.
R&D Magazine: Stacking up three layers of graphene can significantly modify its electrical properties, according to research at the University of California, Riverside. Depending on how the three layers are stacked, some structures are conducting and some are insulating. Graphene is a one-atom-thick sheet of carbon atoms, arranged in hexagonal rings. Its most stable, conducting form occurs when one corner of the hexagons of the middle sheet is located above the center of the hexagons of the bottom sheet, and the top sheet is exactly on top of the lowest sheet, forming what's called a Bernal-stacked trilayer, or ABA pattern. If the top sheet is shifted by the distance of a single atom, to a rhombohedral-stacked trilayer, or ABC pattern, the trilayer arrangement becomes insulating. "Why this happens is not clear as yet. It could be induced by electronic interactions. We eagerly await an explanation from theorists!" said Jeanie Lau, one of the authors of a Nature Physics paper on the subject.
New York Times: A Georgia company, Renmatix, says it has found a method to convert cellulosic biomass—wood chips, switchgrass, and the nonedible parts of crops—into vehicle fuel by just adding water. If it works, the technology could reduce the US’s reliance on oil imports for gasoline in favor of a cleaner-burning and less expensive source of energy, writes Matthew Wald for the New York Times. Renmatix’s process involves putting hardwoods into a small chamber where they are mixed with compressed water at very high temperatures. When the water reaches its supercritical phase, its pH level can be adjusted to turn it into an acid, which is used to harvest the sugars locked up in the material. A small-scale prototype has been built, but the next challenge will be to step up the process to a large-scale commercial refinery.
Nature: Fluorescent labels have helped surgeons spot cancerous ovarian cells smaller than a millimeter in size. About 90% of malignant ovarian tumors have high numbers of receptors for the molecule folate. Vasilis Ntziachristos of the Technical University of Munich in Germany and colleagues attached folate to the fluorescent molecule fluorescein iso-thiocyanate, then injected it into patients. Cells with excess folate receptors, now effectively labeled with the glowing molecule, shone white when viewed with a specially designed camera and light. Surgeons were then able to find and remove cancerous tissue that would otherwise have been indistinguishable from healthy ovarian tissue.
BBC: Highly focused microwaves can be used to extract useful chemical compounds from waste food products, and that processing could take place in homes as well as on an industrial scale. The new technology activates cellulose to release chemicals, can process anything with cellulose in it, and is especially effective with paper and cardboard items. The complexities of global food supply produce a great deal of waste throughout the supply chain; harnessing this material on behalf of the materials and biofuels industries would address the growing problem of waste disposal and provide a renewable source of carbon. A demonstration facility is planned for York, UK, later in 2011.
National Geographic: On a recent close flyby of Saturn's moon Dione, NASA's Cassini spacecraft revealed traces of the moon's passage left in Saturn's magnetic field—evidence of the moon's atmosphere. Dione doesn't have sufficient mass to retain an atmosphere on its own, so the thin layer of air exists only because it's constantly being replenished. The moon resides within Saturn's belt of highly energetic particles and those particles cause Dione's surface ice to break apart chemically, which releases molecules that become the moon's atmosphere. Since that ice is mostly water ice, the atmosphere may be mostly oxygen. Existing data from other Cassini instruments, as well as data gathered during the next flyby on 12 December, may provide clues to whether this is so.
CERN: How do clouds form? The answer has implications for our understanding of climate change, because clouds can reflect the Sun’s radiation back toward space, thus reducing the amount of heat that reaches Earth.
Providing unprecedented insight into cloud formation is the Cosmics Leaving OUtdoor Droplets (CLOUD) experiment at the CERN research center in Switzerland. Researchers there have been studying the effects of cosmic rays on the formation of atmospheric aerosols—tiny particles suspended in the atmosphere—thought to provide the seeds that form cloud droplets.
By current estimates, about half of all cloud droplets begin with aerosols. Trace sulfuric acid and ammonia vapors are used in all of CLOUD's atmospheric models as the genesis for droplet production, but the mechanism and rate by which they form clusters together with water molecules have remained poorly understood.
The CLOUD experiment simulates atmospheric conditions inside a chamber and uses CERN’s Proton Synchrotron accelerator to provide an artificial and adjustable source of cosmic radiation. Results confirm that a few kilometers up in the atmosphere sulfuric acid and water vapor can rapidly form clusters, and that cosmic rays enhance the formation rate by up to 10-fold or more.
However, in the lowest layer of the atmosphere, within about a kilometer of Earth's surface, the CLOUD results show that additional vapors such as ammonia are required to generate the aerosols.
According to Jasper Kirkby, the lead CLOUD spokesperson, the group's results, which were published in Nature, show that these trace vapors, which were assumed to account for aerosol formation, can explain only a small fraction of the observed atmospheric aerosol production.
“It was a big surprise to find that aerosol formation in the lower atmosphere isn’t due to sulfuric acid, water, and ammonia alone,” said Kirkby. “Now it’s vitally important to discover which additional vapors are involved, whether they are largely natural or of human origin, and how they influence clouds. This will be our next job.”
Science: People may soon be able to recharge their cell phones and cameras as they walk. Two researchers at the University of Wisconsin–Madison are developing a device that harvests the mechanical energy produced by walking and converts it to electrical energy. Engineers Tom Krupenkin and J. Ashley Taylor modified an electrostatic capacitor by replacing one of a pair of solid electrodes with an electrically conductive liquid. The liquid electrode allows for a smaller gap between it and the solid electrode, and thus the pair achieves greater capacitance and voltage. If scaled up to the size that would fit a typical shoe, the device could harvest 2 watts of power, the researchers reported yesterday in Nature Communications. They have started a company, InStep NanoPower, to market their product. Although the device won’t eliminate batteries, it could lengthen the time between charges.
Telegraph: Researchers at the UK’s University of St. Andrews may have discovered a new source of diamonds: a candle flame. Previous work had already shown that hydrocarbon molecules at the bottom of the flame are converted into carbon dioxide by the time they reach the top. To find out what happens in between, Wuzong Zhou and coworkers examined particles from the center of the flame and identified samples of all four known forms of carbon, including diamond. “Unfortunately the diamond particles are burned away in the process, and converted into carbon dioxide,” said Zhou. But if a way of extracting the particles could be discovered, it could lead to new methods of manufacturing diamonds. Their results have been published in Chemical Communications.
Nature: Researchers have been refining a computer modeling tool that can screen millions of organic molecules for specific properties. Once they’ve narrowed down the choices, they hand them off to chemists to synthesize. "It's how the pharmaceutical people do it: the theorists give a ranking to the experimentalists," says Alán Aspuru-Guzik of Harvard University. "We're trying to save experimental time." Yesterday in Nature Communications, Aspuru-Guzik and colleagues identified the best organic semiconductor yet discovered, in terms of its ability to transport electric charge, and they have passed its structure on to chemists at Stanford University for development. Now the researchers are collaborating with IBM in a search for a new generation of flexible and lightweight solar cells; they are screening molecules for a host of properties involved in converting sunlight into electrical energy.
Chemical and Engineering News: A team of chemists at Rice University has shown how to prepare graphene from everyday materials, including grass, a cockroach leg, bulk polystyrene, chocolate, and even Girl Scout cookies. As detailed in a paper published online at ACS Nano, James Tour and colleagues placed a solid sample on copper foil in a quartz boat and briefly heated the material to 1050 °C under a low-pressure hydrogen–argon flow. Graphene formed on the back side of the foil, while a residue of other elements remained on the sample side. Graphene has been touted as a miracle material for its toughness and conductivity since its discovery by Nobel Prize–winning scientists Andre Geim and Konstantin Novoselov. Tour, who wanted to show that graphene can be made from just about anything with carbon, hopes that production costs will drop quickly as commercial interests develop methods to manufacture it in bulk.
Daily Mail: A research team at the University of Nottingham campus in Ningbo, China, has developed a material that, when applied to the walls of a room, allows them to absorb and store excess heat and release it later. Jo Darkwa and Oliver Su said the phase-change material, or PCM, will work as a spray, forming a microscopic film on surfaces. When the air in a PCM-treated room rises above a certain temperature, the particles in the spray absorb the excess heat and melt, but instead of dripping they are held in place by a special coating. When the room temperature decreases, the material becomes a solid, releasing the heat back into the room. Darkwa and Su believe the material could both save energy and reduce carbon emissions.
Science: Like little batteries, bacteria have two charges: positive on the outside of their cell membranes, negative on the inside, writes Sara Reardon for Science. And as with batteries, that division of charge is their power source. By pumping protons across their membrane, bacteria can make energy, spin their flagella so they can swim, and drive the pumps that bring in food. Researchers have now found that Escherichia coli drop the voltage difference for a brief moment and depolarize, much as neurons do when they fire. The phenomenon could help explain how some bacteria resist antibiotics: By depolarizing their membranes, the bacteria may be able to kick out charged molecules, such as toxins, that they’ve accumulated.
Science Daily: A University of Georgia researcher has invented a new technology that can render natural and synthetic materials, such as clothing and medical linens, permanently germ-free. Jason Locklin developed the antimicrobial treatment to kill a wide spectrum of bacteria, yeasts, and molds that can cause disease, create stains, and produce odors. It is inexpensive and can be applied to textiles using solution casting or spray coating either during or after the manufacturing process, and it remains fully active after multiple hot-water laundry cycles. Thin films of the new technology can also be used to change other surface properties of both cellulose- and polymer-based materials, including color, reflectance, absorbance, and iridescence. Locklin, who has published his results in Applied Materials and Interfaces, expects the process to be of special benefit to healthcare facilities and hotels, which are prone to the proliferation and spread of very harmful microorganisms.
BBC: Researchers have been working on a new technology to decontaminate water in developing countries. It involves coating grains of sand with an oxide of graphite, a widely available material commonly used as pencil lead. Sand has been used to purify water since ancient times. Although fine sand is more effective than coarse when cleaning water of pathogens, organic materials, and heavy metal ions, water drains much more slowly through fine sand than coarse. "Our product combines coarse sand with functional carbon material that could offer higher retention for those pollutants, and at the same time gives good throughput," explained Wei Gao of Rice University, one of the authors of a study published in Applied Materials and Interfaces. In addition, lead scientist Pulickel Ajayan, also at Rice, said the graphite oxide could be modified to make it more selective and sensitive to certain pollutants. Because the necessary materials are cheap and readily available and the graphite-coated sand grains can be synthesized using room-temperature processes, the researchers say the method would be very cost efficient.
Wired: Two new elements have been officially added to the periodic table: 114 and 116. They are the heaviest members of the table yet, with atomic weights of 289 and 292 atomic mass units, respectively. First discovered more than a decade ago, the two elements were recently granted official status by the International Union of Pure and Applied Chemistry and the International Union of Pure and Applied Physics following extensive experimentation and a three-year review process. A key criterion was how the new elements relate to preexisting known elements. Official names have yet to be decided; the discoverers at the Joint Institute for Nuclear Research in Dubna, Russia, have proposed flerovium, after Soviet nuclear physicist Georgy Flyorov, and moscovium, after the administrative territorial division Moscow Oblast.
Science: Long thought to be the reason behind Spain’s crippling inflation in the 16th and 17th centuries, the massive amounts of silver shipped in from the Americas may not even have entered Spain’s currency until at least 100 years later, according to a study conducted by a group at the University of Lyon in France and published in the Proceedings of the National Academy of Sciences. Anne-Marie DeSaulty and colleagues used mass spectrometry to measure the ratios of several metal isotopes in 91 old coins from ancient Greece and Rome, medieval Europe, 16th–18th century Spain, and Latin America, writes Sara Reardon for Science. The ratio of the silver-109 isotope to silver-107 was much higher in New World coins than in the European coins. That suggests that even though American silver arrived in Spain in 1550, the Spanish waited well over 100 years before using it for their own currency. DeSaulty believes instead that the Spanish probably used the imported silver for trade. Some people have questioned, however, whether her sample of coins was large enough to support her conclusions and whether the importation of all that silver could have caused the inflation even if it weren’t minted into coins.
New Scientist: Four science teams—from Europe, Australia, China, and the US—are racing to retrieve the first million-year-old sample from Antarctica’s ice. Ancient ice could hold clues to past changes in Earth’s climate. Using such ice samples, scientists could study the concentration of carbon dioxide in the ancient atmosphere by analyzing the air trapped in tiny bubbles within the ice. A decline in carbon dioxide concentration could explain the advent of an ice age, for example. One researcher, Robin Bell of the Lamont-Doherty Earth Observatory of Columbia University, and her colleagues have come across a potential problem with the hunt, however. They have found that ice sheets in Dome A, one of the drilling sites, is growing from the bottom up. This could mean that any ancient ice that was once there has melted and been replaced.
Nature: Adding iron or cobalt to polyethylene boosts the ubiquitous plastic's propensity to oxidize in sunlight. Bags made from degradable polyethylene duly fall apart, but whether the fragments that remain are environmentally friendly has been an open question. Now, as Nature's Daniel Cressey reports, the UK's Department for Environment, Food, and Rural Affairs (DEFRA) has found that the fragments persist for much longer than the 2–5 years it takes for a bag exposed to the elements to break apart. According to DEFRA, the fragments should not be included in compost lest they ruin it.
Nature: A new kind of self-repairing plastic has been developed by Christoph Weder, of the University of Fribourg in Switzerland, and colleagues. Unlike other self-repairing materials, which are heated until they melt and then allowed to cool and reharden, the new material requires only exposure to ordinary light. The rubbery material consists of small chains of polymers interspersed with metal ions. When light hits the material, the metal heats up, causing the polymer chains to break apart and flow into cracks in the damaged area. When the light is turned off, the molecules reassemble themselves and thus repair the fracture. Currently, the plastic must be thin enough that light can penetrate it, but it's possible that fiber-optic cables could be incorporated to provide light throughout the material. The new plastic could extend the lifetime and improve the durability of myriad polymer-based products and could also be used in varnish and paint. The team's results were published online yesterday in Nature.
New Scientist: Amy Prieto and colleagues at Colorado State University in Fort Collins are developing a rechargeable battery that is smaller, lighter, and more rapidly rechargeable than current electric car batteries. According to Helen Knight, writing for New Scientist, the battery has hairbrush-like electrodes that can be charged in just a few minutes. Instead of the current design used in lithium-ion batteries, which consist of a graphite anode and lithium cathode with an electrolyte sandwiched between them, Prieto's battery uses nanowire anodes made of copper antimonide. The large surface area of the millions of nanowires means they can store twice as many lithium ions as the same amount of graphite. Prieto, who has founded the company Prieto Battery, discussed the team's prototype battery at the American Chemical Society meeting this week in Anaheim, California.
Guardian: Firefighters may one day put out a fire by waving an electric wand at the flames. According to Ludevico Cademartiri from Harvard University and colleagues, they have succeeded in extinguishing an 18-inch flame by using an electrified metal wire. Basing their research on an observation made some 200 years ago that electricity can change the shape of flames, the team found that oscillating AC voltage charges the carbon particles in the flames, creating an organized flow that pushes the flames away from the fuel source. "Essentially, the [electrical field] separates the region that's hot and burning from the unburnt fuel, so that fuel will not continue to burn," said Kyle Bishop, a researcher who worked with the team.
Science: A silicon wafer the approximate shape and size of a playing card turns sunlight and water into hydrogen and oxygen and may provide a source of hydrogen fuel that's both easy to tap and practically limitless. The new device isn't the first one capable of splitting water, writes Robert Service for Science, but it may be the most cost effective. Prior attempts used catalysts that were very expensive or unstable. Daniel Nocera of MIT has addressed these issues with a new catalyst compound of three metals, and he and his team have been using the device for a week with no drop in efficiency. According to Nocera, the device converts 5.5% of the energy it absorbs into hydrogen fuel. He has not revealed which metals make up the catalyst; his work is not yet published.
BBC: The main chemical in the curry spice turmeric could be the basis for cheap explosives detectors, writes Jason Palmer for BBC News. Abhishek Kumar, of the University of Massachusetts, Lowell, and his colleagues has discovered a means of using that chemical's fluorescence properties to detect the presence of explosives: As the chemical gathers molecules of explosive material in air, changes in the chemical's light-emitting properties can be measured. The team dissolved curcumin in a polymer and used the mixture to make thin films. When an inexpensive light source, such as an LED, is shone on the film, the light dims if explosives are present. This application of fluorescence spectroscopy was presented at the recent American Physical Society's meeting in Dallas, Texas.
Hartford Courant: Juha Javanainen, a physicist at the University of Connecticut's Storrs campus, has been sentenced to community service and a year of probation following an explosion that took place last year in the backyard of his house. His son set off the explosion, having put together a homemade bomb from chemicals his father had bought for him. When the police and its bomb squad arrived at the house, they found that some of the unused chemicals were too volatile to remove. After evacuating the immediate neighborhood, the bomb squad detonated the chemicals.
New York Times: As the price of oil continues to rise, one company, Gevo in Englewood, Colorado, is pursuing a greener alternative to the fossil fuel: It has just bought a plant that turns corn into ethanol—used as vehicle fuel—and plans to convert the plant to make a different chemical, isobutanol, which is a building block for many other chemicals. Isobutanol is easily converted to butanol, which can be used as fuel as well as in rubber and plastics. A green aspect of this process is that when making rubber and plastics, butanol not only replaces the oil but also becomes a “carbon sink,” a place where carbon dioxide, a greenhouse gas, can be stored after it is pulled out of the atmosphere.
Nature: The acidity of seawater has climbed by 30% over the past 150 years, and some regions have already become corrosive enough to inhibit the growth of corals and other species for part of the year. Carbonic acid is produced when the oceans absorb carbon dioxide, which reacts with the water. Unless nations sharply curb their emissions, atmospheric CO2 is expected to at least double from its preindustrial concentration by sometime in the second half of this century. Countries are only now revving up the coordinated research programs needed to assess how marine ecosystems will react to the increasingly acidic waters. Quirin Schiermeier examines this problem in his Nature news story.
New York Times: Researchers have for years been trying to replicate spiders’ silk for use in many different products. Spiders’ silk is not a single material but varies from sticky toothpaste-like mush to strong, stretchy draglines and can be stronger than steel or bulletproof like Kevlar. Recent applications by Tufts University researchers include electrode arrays that are printed on flexible, degradable silk films, which may one day be used to treat epilepsy without producing the scarring that larger implanted electrodes do, and a coil made of silk substrate and gold that can help tell when food goes bad. Yet some of the qualities of actual spiders' silk, such as the complex ways proteins in natural silk are folded to give each silk its unique properties, still elude researchers.
Science: Studies of the ruins of the giant Buddhas of Bamiyan in Afghanistan, which were destroyed by the Taliban a decade ago, reveal new details about how they were made and what they originally looked like. The statues—originally 38 and 55 meters high—were carved into the sandstone cliffs of the Bamiyan Valley some 1500 years ago. Employing mass spectrometry analysis, a team led by Erwin Emmerling of the Technical University of Munich in Germany used organic material in the clay layers in the rubble to determine more precisely when the statues were created and found that, at one time, one was red and the other white. "The Buddhas once had an intensely colorful appearance," Emmerling said in a statement, and they were painted over several times.
BBC: Nitrogen is the fourth most abundant element in the universe, the most abundant gas in Earth's atmosphere, and an essential ingredient in proteins, DNA, and other biomolecules. But getting nitrogen into the right chemical form to give rise to life is chemically tricky. Now, Sandra Pizzarello of Arizona State University and her colleagues have found a possible answer. By using hot, pressurized water, Pizzarello was able to dissolve and subsequently analyze an otherwise insoluble organic component of a meteorite found in Antarctica. Among the molecules they found was ammonia. Unlike N2, ammonia readily participates in organic chemistry. Pizzarello speculates that meteorites could have brought ammonia to prebiotic Earth, thereby giving life the chemical impetus needed to get going. The team reported their results in the Proceedings of the National Academy of Sciences.
New York Times: An Israeli scholar says he has identified the first known physical sample of tekhelet—the shade of blue used for ritual prayer tassels and for ceremonial robes worn by high priests. Zvi Koren, a professor specializing in the analytical chemistry of ancient colorants, analyzed a 2000-year-old piece of dyed fabric recovered from Masada, King Herod’s Judean Desert fortress. The exact shade of blue used has been a mystery for centuries. The dye was produced from the secretion of the sea snail, still found on Israeli beaches, but the technique of producing the dye was lost some time after the Jews were exiled from Israel in AD 70.
New Scientist: Researchers have built a computer program that can represent atoms and other objects as shapes in four and five dimensions as well as three, and provide new insights into the properties of those atoms. The software turns the shapes into differential equations, then examines the shapes' flow, looking for the unique patterns that signify an atom. Tom Coates, a mathematician at Imperial College London, and his colleagues plan to generate lists of shapes in higher dimensions and then group the shapes in each list according to their properties, much as atoms are grouped in the periodic table of elements. The work could provide insights into string theory and superconductivity.
Science: The exoskeletons of ants, ticks, and other arthropods, both ancient and modern, are made up of proteins, sugars, and calcium carbonate. When an arthropod dies, microbes begin eating the first two components of the shell. The upshot for paleontologists is that little of an ancient arthropod's exoskeleton survives as a fossil. But some exoskeleton does survive, and now, as Science's Sid Perkins reports, we know why. George Cody of the Carnegie Institution of Washington and his collaborators applied x-ray absorption near edge structure (XANES) spectromicroscopy to the fossilized remains of two arthropods, a 310-million-year-old land scorpion and a 417-million-year-old sea scorpion. Comparison with modern scorpions revealed that what remained of the fossilized exoskeletons had been chemically modified, possibly by chemicals from the exoskeleton's original waxy coating. When the scorpions were alive, the waxy coating prevented their exoskeletons from drying out. When they died, the coating decomposed, releasing chemicals that stabilized the exoskeleton's protein–sugar complex.
Nature: Laying one kind of semiconductor nanowire athwart another kind of semiconductor nanowire creates a tiny transistor. Arranging multiple nanowires in a grid-like fashion creates a device that can perform elementary logic. That's what Harvard University's Charles Lieber and his collaborators have done. Reporting in today's Nature, Lieber describes making and operating "logic tiles" that consist of 496 transistors and measure 960 μm2 in area. The tiles' programming ability arises from the crossings' configuration and from the sequence in which the wires are activated.
Economist: A Florida company, Planar Energy of Orlando, is about to complete a pilot production line that will print lithium-ion batteries onto sheets of metal or plastic, like printing a newspaper. Thin-film printing methods of this sort are already used to make solar cells and display screens, but no one has yet been able to use them on anything like an industrial scale with batteries. The process promises smaller, cheaper, more powerful batteries for consumer electronics and, eventually, for electric cars.
Economist: Although people don’t usually want iron in their water because it has a disagreeable taste and leaves stains, a Florida company plans to use a chemically unusual form of iron to clean water up. Ferrates, which are compounds of iron and oxygen, destroy bacteria and viruses, and attract other chemicals in water, including dissolved metals, and precipitate them for easy removal. Plus, the iron in ferrates precipitates too, leaving pure water behind. Ferrates’ reactivity, however, makes them unstable and difficult to store. The trick, says Luke Daly of Ferrate Treatment Technologies in Orlando, will be to make ferrates on site, for instant use.
Nature: Green chemistry is becoming an increasingly popular field, now that chemical companies struggle to deal with increasingly stringent environmental regulations. The term was introduced in 1991 by Paul Anastas, then a 28-year-old staff chemist with the Environmental Protection Agency. Anastas's conception of green chemistry centered on redesigning chemical processes from the ground up—making industrial chemistry safer, cleaner, and more energy-efficient. Nature's Katharine Sanderson takes an in-depth look at green chemistry, its benefits, and its costs.
Telegraph: Thousands of pounds are being spent on special grit for roads near London’s art galleries after experts warned that salt spreading is ruining some of the finest masterpieces. The substance, called sodium formate, costs about 10 times the price of normal rock salt. The experts discovered that visitors were tracking salt and grit into galleries, which causes a chemical reaction that leads to permanent damage to priceless paintings. Works most at risk are those containing the traditional red pigment vermilion, commonly used in old master paintings.
NPR: For six years, workers processed nuclear waste at a plant outside Buffalo, New York. In its short life, the West Valley Demonstration Project polluted soil, air and water, and may have sickened employees. Four decades later, hundreds of cleanup workers are still at the site decontaminating buildings that will eventually be torn down. Now, workers are preparing to install a massive underground wall designed to stop the spread of a radioactive plume that threatens the region's groundwater. As the West Valley cleanup nears completion, reporter Daniel Robison looks at an environmental disaster that led to a new understanding of how to deal with nuclear waste.
Science News: Just as the weight listed on your driver’s license doesn’t necessarily reflect your actual poundage, the official atomic weights of the chemical elements are actually more like ballpark estimates than precise constants, according to Rachel Ehrenberg writing for Science News. In acknowledgment of that natural variation, the official weights of 10 chemical elements will no longer be expressed as single numbers, but as ranges. The adjustments, published online on 12 December in Pure and Applied Chemistry, are the first in an overhaul of the atomic weight of almost every element on the periodic table.
Ecoseed: Scientists at the University of Missouri used cinnamon to replace almost all the toxic chemicals needed for making gold nanoparticles. They mixed gold salts with cinnamon and stirred the mixture in water. Kattesh Katti, professor of radiology and physics in the School of Medicine and the College of Arts and Science, said the process is environmentally friendly because it uses no electricity and utilizes no other toxic chemicals. Gold nanoparticles are used in electronics and healthcare. Katti uses his for cancer treatment, which was the focus of his study published in Pharmaceutical Research.
Daily Mail: Researchers at MIT are investigating the possibility of using a rare metal, ruthenium, that can absorb sunlight, store the energy, and release it as pure heat to create a “rechargeable heat battery.” When molecules of fulvalene diruthenium absorb sunlight, they change shape into a long-lived semistable state. When the molecules interact with a catalyst, they snap back into their original form, releasing heat. Such a system could be far more effective than conventional solar-thermal ones, which require insulation and gradually lose heat. The drawback is the metal’s rarity—ruthenium comes from the same family as platinum.
Daily Mail: For the first time, an oxygen atmosphere has been discovered on a world other than Earth—on Saturn's second-largest moon, Rhea. In March NASA's Cassini spacecraft flew though the moon's outer atmosphere, scooping up and identifying molecules in situ. Published in Science, the findings reveal an extremely thin atmosphere with an oxygen density about 5 trillion times less than that of Earth. The paper's authors speculate that the atmosphere is sustained by high-energy particles bombarding the moon's icy surface and kicking up atoms, molecules, and ions.
Daily Mail: Recent advances in nanotechnology could turn Willy Wonka’s Three-Course Dinner Chewing Gum into reality. In Roald Dahl’s 1964 novel Charlie and the Chocolate Factory, the gum first tastes like tomato soup, then roast beef and baked potato, and finally blueberry pie and ice cream. Now, food scientist Dave Hart and coworkers at the UK’s Institute of Food Research (IFR) say they have cracked the secret behind creating such a stick of chewing gum. Hart and his team are experimenting with creating different flavor layers separated by a tasteless gelatin, with a final dessert taste at the center, encapsulated in a high-tech gel called Gellan. “Tiny nanostructures within the gum would contain each of the different flavors. These would be broken up and released upon contact with saliva or after a certain amount of chewing,” says Hart.
Nobelprize.org: Richard Heck, Ei'ichi Negishi, and Akira Suzuki are the winners of this year's Nobel Prize in Chemistry. The three researchers have each devised chemical processes that use a palladium catalyst to form carbon–carbon bonds between certain types of organic molecule. In processes named after each of the winners, reactants bind to palladium, whose empty 5s orbital provides a venue for the reactants to adjust their molecular orbitals to configurations that favor binding. Naturally occurring drugs, including the anticancer drug Taxol (shown here), are among the molecules that form via palladium-catalyzed reactions. Heck is affiliated with the University of Delaware in Newark. Negishi is affiliated with Purdue University in West Lafayette, Indiana. Suzuki is affiliated with Hokkaido University in Sapporo, Japan.
The Tennessean: Arnold Burger and fellow Fisk University researchers have just made it easier for Homeland Security agents to tell the difference between a dirty bomb and a banana.
Fruit, such as a banana contains potassium, which can give off the same radiation signature as plutonium.
The Fisk researchers, in partnership with Radiation Monitoring Devices Inc, and Lawrence Livermore and Oak Ridge National Laboratories, have developed a cheaper, easy-to-produce, new type of radiation-detecting crystal that is more accurate than most of the devices on the market.
The group has just won an R&D 100 magazine award, given to the 100 cleverest inventions of the year for their work.
New Scientist: Several groups of researchers have been working toward deriving energy from sunlight and water—much as plants do. A team at MIT found a revolutionary way to split a water molecule into oxygen gas and hydrogen ions, which required far less electricity than conventional electrolysis, by using a cheap cobalt–phosphate catalyst and titanium oxide electrodes. Another team, from the University of Washington in Seattle, used MIT’s photovoltaic technology to develop a more-energy-efficient photoelectrochemical electrode—although it cannot as yet generate enough power to run on its own. Both methods generate only hydrogen ions, which still need to be turned into hydrogen gas. Some of their results have been published in Energy and Environmental Science.
Nature: Leo Gross of IBM's research center in Zurich, Switzerland, and his coworkers have used an atomic force microscope (AFM) and a scanning tunneling microscope (STM) to determine the structure of cephalandole A, an organic molecule found in a deep-sea-dwelling bacterium. Cephalandole A contains three six-membered benzene rings and one five-membered pyrrole ring. Four possible structures had previously been identified. As Nature’s Philip Ball reports, Gross and his team immobilized molecules of cephalandole A on a crystal surface, then probed their electronic structure with an STM and their shape with an AFM. Drug companies are interested in cephalandole A. One of its chemical relatives, camptothecin, showed promise as an anticancer drug.
Physics Today: NASA, US Navy and university researchers have successfully demonstrated the first robotic underwater vehicle to be powered entirely by natural, renewable, ocean thermal energy, that can be scalable to a wide range of autonomous crafts capable of virtually indefinite ocean monitoring for climate and marine animal studies, exploration and surveillance.
Chemistry World: Researchers in the US have shown that perovskites—a class of mixed oxide minerals—can perform as well as platinum in certain types of catalytic converter for removing pollutants from diesel exhaust. Although it is early days in the research, the finding could eventually result in cheaper, more robust catalytic converters for diesel engines that do not rely on expensive and scarce platinum group metals.
Related link
Strontium-doped perovskites rival platinum catalysts for treating nox in simulated diesel exhaust
NPR: At the American Chemical Society meeting in San Francisco last week, scientists presented work on everything from the greenhouse gas emissions of livestock to the effect of human skin oils on office air quality. Ira Flatow and guests discussed these stories and other news from the meeting on Science Friday.
Science: Have you noticed that computers have stopped getting faster?
Microprocessor clock frequencies plateaued around 2005, a stunning break after a decades-long run of ever-compounding improvements in computing speed.
The cause is a breakdown of the simple constant-electric-field scaling rules that had guided the shrinking of field-effect transistors for decades. As transistors shrank, they switched faster and used less power to switch but a certain amount of power is still needed to switch them from ON to OFF and vice versa.
Companies continue to shrink the transistor, emphasizing the increasing number of parallel processors (cores) they can place on a single silicon chip. But with power supply voltages stuck at about 1 V, increasing clock frequencies as in the past would result in unsupportable increases in power dissipation and heat generation. The transistor is rapidly approaching its ultimate physical limits.
The only way to decisively break the power dissipation bottleneck is to change the physics of transistor operation in ways that facilitate further reduction of operating voltage says Thomas N. Theis and Paul M. Solomon in Science.
Various: A study just published in the Proceedings of the National Academy of Sciences, by Jessica Whiteside of Brown University in Rhode Island and colleagues, has come up with a plausible explanation for the rise of the dinosaurs such as Tyrannosaurus rex.
Their predecessors, aetosaurs, phytosaurs, shuvosaurs among others, and other common lifeforms of the Triassic period went extinct by the geological chaos that created the North Atlantic Ocean.
The evidence is in the large fluctuations of between different types of carbon isotopes embedded in the rock (carbon-12 and carbon-13). These fluctuations reflect perturbations of the carbon cycle including a transient increase in CO2 around the time giant volcanic eruptions split Pangaea, the single super continent that made up the land mass at the time.
Related links
Compound-specific carbon isotopes from Earth's largest flood basalt eruptions directly linked to the end-Triassic mass extinction PNAS
Epic volcanism wiped out dinosaurs’ primary competitors BBC
The rise of the dinosaurs: Easy come, easy go The Economist
Physics Today: A new radiocarbon dating technique that can determine the age of ancient mummies, old artwork, and other relics without causing damage was announced yesterday at the annual meeting of the American Chemical Society held in San Francisco, California.
"This technique stands to revolutionize radiocarbon dating," said Marvin Rowe, of Texas A&M university at Qatar, who led the research team. "It expands the possibility for analyzing extensive museum collections that have previously been off limits because of their rarity or intrinsic value and the destructive nature of the current method of radiocarbon dating."
Science News: Recent studies show that the oceans may hold more “garbage patches” of fine plastic flotsam than scientists realized and that the fragments extend well below the sea surface.
Most of these items are the size of fingernail clippings or smaller. They are the wave-shattered remnants of items such as rubbish, abandoned fishing gear and floats from fishing nets and scientific instruments. These plastic bits are especially common in a region of the Pacific Ocean southwest of California that is sometimes called the Great Pacific Garbage Patch.
Recent cruises reveal that there’s more garbage in this patch than often meets the eye, oceanographer Giora Proskurowski of the Sea Education Association in Woods Hole, Mass., reported February 24 at the American Geophysical Union’s Ocean Sciences meeting.
The Economist: Ludvig Edman of Umea University and Nathaniel Robinson of Linkoping in Sweden may have found a way to tweak organic light-emitting diodes, or OLEDs, by blending the semiconducting polymer with potassium trifluoromethylsulfonate. The result is a sheet similar to wallpaper that can illuminate itself at the flick of a switch.
Science News: There’s a new heavy in town. Element 112, a “superheavy” element with an atomic mass of 278, has been officially named copernicium, the International Union of Pure and Applied Chemistry announced 19 February. It is the heaviest named element to date.
redOrbit: Unless you're interested in isotopic labeling, neutrons don't figure much into chemistry. Neutral in charge and a bit bigger than a proton, the neutron neither gives an atom its name nor determines much about its reactivity.
But neutrons have some unsung properties that make them useful for investigating matter. Because they are neutral, they can penetrate deeper into a sample than electrons can. Because they have mass and spin, they have a magnetic moment and can probe magnetism. Because they interact with nuclei rather than electron orbitals, they are sensitive to light elements and can even distinguish between hydrogen and deuterium. And they're nondestructive. These features are inspiring researchers to use neutrons to analyze a variety of materials, from coal and complex fluids to cell membranes and membrane proteins and including magnetic materials.
Nature News: The burning of fossil fuels such as coal and oil releases carbon dioxide that alters the balance of carbon isotopes naturally found in the environment—an effect that is now being found in food, reveals a US study.
Science: The different colors on the surface of a soap bubble arise from the interference of light waves reflecting from the outer and inner surface of the liquid film. As the thickness of the film varies, so will the wavelength of light that undergoes constructive interference and remains visible.
According to quantum mechanics, even material particles such as electrons behave like waves. In addition to their charge, electrons also have two distinguishable spin states, spin-up and spin-down.
In Science, Petta and associates demonstrate beam splitting and interferometry for the spin degrees of freedom of two electrons on a semiconductor chip.
Related link
A coherent beam splitter for electronic spin states
New Scientist: Two crystals identical in appearance and chemical formula—and even with the same crystal symmetry—turn out to differ wildly in their capacity for storing hydrogen, much to the surprise of the chemists who made them.
The finding hints that there may be a previously unknown class of crystals that would be useful for gas storage or catalysis.
Related link
An unusual case of symmetry-preserving isomerism
Physics Today:Springtime ozone levels above western North America are rising primarily due to air flowing eastward from the Pacific Ocean, a trend that is most significant when the air originates in Asia.
Such increases in ozone could make it more difficult for the US to meet Clean Air Act standards for ozone pollution at ground level, according to a new international study in Nature. The study analyzed large sets of ozone data captured since 1984.
"In springtime, pollution from across the hemisphere, not nearby sources, contributes to the ozone increases above western North America," said lead author Owen R. Cooper, of the University of Colorado at Boulder. "When air is transported from a broad region of south and east Asia, the trend is largest."
The study focused on springtime ozone in a slice of the atmosphere from two to five miles above the surface of western North America, far below the protective ozone layer but above ozone-related, ground-level smog that is harmful to human health and crops. Ozone in this intermediate region constitutes the northern hemisphere background, or baseline level of ozone in the lower atmosphere. The study was the first to pull together and analyze nearly 100 000 ozone observations gathered in separate studies by instruments on aircraft, balloons and other platforms.
Combustion of fossil fuels releases pollutants like nitrogen oxides and volatile organic compounds, or VOCs, which react in the presence of sunlight to form ozone. North American emissions contribute to global ozone levels, but the researchers did not find any evidence that these local emissions are driving the increasing trend in ozone above western North America.
Cooper and colleagues from from the National Oceanic and Atmospheric Administration's Earth System Research Laboratory in Boulder and eight other research institutes used historical data of global atmospheric wind records and sophisticated computer modeling to match each ozone measurement with air-flow patterns for several days before it was recorded. This approach essentially let the scientists track ozone-producing emissions back to a broad region of origin.
This method is like imagining a box full of 40 000 tiny weightless balls at the exact location of each ozone measurement, said Cooper. Factoring in winds in the days prior to the measurement, the computer model estimates which winds brought the balls to that spot and where they originated.
When the dominant airflow came from south and east Asia, the scientists saw the largest increases in ozone measurements. When airflow patterns were not directly from Asia, ozone still increased but at a lower rate, indicating the possibility that emissions from other places could be contributing to the ozone increases above North America.
The study used springtime ozone measurements because previous studies have shown that air transport from Asia to North America is strongest in spring, making it easier to discern possible effects of distant pollution on the North American ozone trends.
Ozone-measuring research balloons and research aircraft collected a portion of the data. Commercial flights equipped with ozone-measuring instruments also collected a large share of the data through the MOZAIC program, initiated by European scientists in 1994. The bulk of the data was collected between 1995 and 2008, but the team also included a large ozone dataset from 1984.
The analysis shows an overall significant increase in springtime ozone of 14 percent from 1995 to 2008. When they included data from 1984, the year with the lowest average ozone level, the scientists saw a similar rate of increase from that time through 2008 and an overall increase in springtime ozone of 29 %.
"This study did not quantify how much of the ozone increase is solely due to Asia," Cooper said. "But we can say that the background ozone entering North America increased over the past 14 years and probably over the past 25 years."
ScienceNOW: Of all the radioactive isotopes left over from nuclear weapons testing and nuclear power plants, cesium-137 is among the most dangerous. The soft, silvery-white metal has a half-life of 30 years, enters the body quickly, and can trigger cancer even decades after exposure. Removing cesium-137 from the environment has proven difficult, but researchers say they have a promising new way to clean it up: a flexible, porous solid that grabs cesium ions much like a Venus flytrap ensnares its prey.
Related link
Selective incarceration of caesium ions by Venus flytrap action of a flexible framework sulfide Nature Chemistry
Nature: The surprising discovery of methane in Mars's atmosphere could be a sign of life there. Researchers are now working out how to find its source, reports Nature's Katharine Sanderson.
Science News: Pulling yourself back together after a breakup can be tough to do. But a new hydrogel has no trouble. Using little more than water, clay, and a new, designer compound, scientists have created a moldable gel that is both strong and can heal itself in seconds when split in two. The gel may advance efforts in tissue engineering and environmentally friendly chemistry.
Nature News: In an accidental discovery, chemists have stumbled on a catalyst that strips only carbon dioxide from the air—ignoring oxygen—and converts it into a useful compound.
Nature News: The latest in a string of high-profile academic fraud cases in China underscores the problems of an academic-evaluation system that places disproportionate emphasis on publications, critics say.
Editors at the UK-based journal Acta Crystallographica Section E last month retracted 70 published crystal structures that they allege are fabrications by researchers at Jinggangshan University in Jiangxi province. Further retractions, the editors say, are likely.
Several sources revealed to Nature that roughly one-third of more than 6000 scientists surveyed across six top institutions admitted to plagiarism, falsification, or fabrication.
In a related news story, Katharine Sanderson discovers that a new publication by US–Chinese company Scientific Research called Journal of Modern Physics had copied papers from the UK's Institute of Physics open-access New Journal of Physics.
NPR: At a once-defunct Polaroid film factory in New Bedford, Massachusetts, the lights are on again and a new industry is rising up inside the ruins of an old one.
The company Konarka makes solar panels, but not the kind most people have seen. These are thin, lightweight, flexible plastic sheets, and that enables them to be used in all sorts of new ways.
"We make what's called plastic solar cells; we call it 'power plastic,' " says Rick Hess, Konarka's chief executive officer.
Related news story
Solar panel thefts heating up
washingtonpost.com: Of the 84,000 chemicals in commercial use in the US—from flame retardants in furniture to household cleaners—nearly 20% are secret, according to the Environmental Protection Agency, their names and physical properties guarded from consumers and virtually all public officials under a little-known federal provision.
The policy was designed 33 years ago to protect trade secrets in a highly competitive industry. But critics—including the Obama administration—say the secrecy has grown out of control, making it impossible for regulators to control potential dangers or for consumers to know which toxic substances they might be exposed to.
Wired.com: Researchers have showed the first functional transistor made from a single molecule. The transistor, which has a benzene molecule attached to gold contacts, could behave just like a silicon transistor.
The molecule’s different energy states can be manipulated by varying the voltage applied to it through the contacts. And by manipulating the energy states, researchers were able to control the current passing through it.
NPR: During the holiday season we see images of lots of geometrically incorrect snowflakes.
Chemist Thomas Koop thinks ice crystals are masterpieces of natural beauty. Unfortunately, he says, "This beauty is sometimes corrupted."
Koop, a professor at Bielefeld University in Germany, says the problem is that many of these images show ice crystals with five or eight sides. In other words, he says, they are scientific abominations.
Related news story
Christmas card snowflakes 'corrupt nature' by defying laws of physics
ScienceNOW: Nitrogen atoms are needed to make many important chemicals from drugs to fertilizers.
But getting those atoms into chemicals is challenging, because nitrogen molecules are tough nuts to crack.
They consist of two atoms sharing a stubborn triple bond, which chemists can break up only by scorching them with temperatures of up to 500 °C. And that results in the simple chemical ammonia, which needs further processing to produce more complicated compounds.
Now chemists have bypassed the energy-intensive reaction and devised a new one that splits molecular nitrogen at room temperature and synthesizes a common fertilizer.
Wired.com: Inspired by videos of renowned hacker Johnny Chung Lee who turned the $40 Nintendo Wiimote remote controller into a finger-tracking device and a touchscreen white board, physicist Rolf Hut of Delft University of Technology in the Netherlands has built a Wiimote wind sensor.
"It was just a bendy pole with an empty bottle on top with an LED light on the bottle," Hut said. "And it swayed in the wind."
The Wiimote can track just about anything: All that's needed is an LED light. Hydrologist Willem Luxemburg, also from Delft University of Technology demonstrated a hacked water-level sensor made from a Wiimote and a plastic boat at the meeting of the American Geophysical Union in San Francisco.
Science: Conventional solar technologies produce electricity, but most transportation fuel comes from oil. A new class of solar chemical reactors aims to make liquid fuels from air, water, and sunshine.
NYTimes.com: In a finding that is sure to add to one of the longest-running debates in music, a detailed analysis of the varnish on five instruments made by Antonio Stradivari reveals that he coated the wood with a rather humdrum mix of oil and resin. Those looking to the varnish as the secret to the master Italian violin maker’s renown, the study suggests, had best look elsewhere.
Nature: With microfluidic devices gaining prominence for many applications in chemistry and biology, the hunt is on to find ways of accurately controlling the motion of liquid droplets. In Angewandte Chemie, Antoine Diguet et al. describe a method for using light to trap and move oil droplets floating on an aqueous solution.
Related Link
Photomanipulation of a droplet by the chromocapillary effect
