Silicon-air batteries are viewed as a promising and cost-effective alternative to current energy storage technology. However, they have thus far only achieved relatively short running times. Jülich researchers have now discovered why.
In theory, silicon-air batteries have a much higher energy density and are also smaller and lighter than current lithium-ion batteries. They are also environmentally friendly and insensitive to external influences. Their most important advantage, however, is their material. Silicon is the second most abundant element in the Earth's crust after oxygen: it is cheap and its reserves are practically inexhaustible.
Cornell University biological engineers have deciphered the cellular strategy to make the biofuel ethanol, using an anaerobic microbe feeding on carbon monoxide - a common industrial waste gas.
"Instead of having the waste go to waste, you make it into something you want," said Ludmilla Aristilde, assistant professor in biological and environmental engineering. "In order to make the microbes do our work, we had to figure out how they work, their metabolism."
Aristilde collaborated with her colleague Lars Angenent, professor of biological and environmental engineering, on the project. She explained, "The Angenent group had taken a waste product and turned it into a useful product."
To make biofuel from inorganic, gaseous industrial rubbish, the researchers learned that the bacterium Clostridium ljungdahlii responds thermodynamically - rather than genetically - in the process of tuning favorable enzymatic reactions.
At first glance, magnetite appears to be a rather inconspicuous grey mineral. But on an atomic scale, it has remarkable properties: on magnetite, single metal atoms are held in place, or they can be made to move across the surface. Sometimes several metal atoms on magnetite form small clusters. Such phenomena can dramatically change the chemical activity of the material. Atomic processes on the magnetite surface determine how well certain metal atoms can serve as catalysts for chemical reactions.
Scientists at TU Wien (Vienna), together with colleagues from Utrecht University, can now watch single platinum atoms form tiny clusters. Carbon monoxide plays a dual role in this process: It allows single platinum atoms to move and form pairs, and then it holds these pairs together for a long time. Only by increasing the temperature can the pair-bonds between platinum atoms can be broken.
Solar cells have been manufactured already for a long from inexpensive materials with different printing techniques. Especially organic solar cells and dye-sensitized solar cells are suitable for printing.
-We wanted to take the idea of printed solar cells even further, and see if their materials could be inkjet-printed as pictures and text like traditional printing inks, tells University Lecturer Janne Halme.
When light is absorbed in an ordinary ink, it generates heat. A photovoltaic ink, however, coverts part of that energy to electricity. The darker the color, the more electricity is produced, because the human eye is most sensitive to that part of the solar radiation spectrum which has highest energy density. The most efficient solar cell is therefore pitch-black.
Solar Impulse 2 touched down in Abu Dhabi today, becoming the first fuel-free plane to successfully circumnavigate the globe. OK, so the 22,000-mile trip took a minute: The solar-powered bird lifted off from the same city in March 2015. But despite a few setbacks, the plane and Swiss pilot Bertrand Piccard (who took shifts with fellow flyer André Borschberg) touched down without incident.
Solar Impulse 2 is a seriously nifty machine. Its 236-foot wingspan makes it wider than a Boeing 747, but the thing is just 5,000 pounds. 17,000 rigid, photovoltaic panels charge four uber-efficient batteries, which make up nearly a third of the weight. Its four 17.4-horsepower motors definitely aren’t the fastest: The plane tops out around 90 mph, and traveled at an average of 38 mph across the Pacific. (Yeah, we’d honk at it on the highway, too.)
The Zika virus poses a negligible health threat to the international community during the summer Olympic Games that begin next month in Rio de Janeiro, Brazil, according to researchers at Yale School of Public Health (YSPH).
In a worst-case scenario, an estimated 3 to 37 of the thousands of athletes, spectators, media, and vendors traveling to Rio for the Olympics will bring the Zika virus back to their home countries, the researchers concluded.
Hurricane Georgette is a major hurricane in the Eastern Pacific Ocean. NASA-NOAA's Suomi NPP satellite provided a visible image of the powerful storm that showed a clear eye.
On July 24, at 21:20 UTC (5:20 p.m. EDT) the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard NASA-NOAA's Suomi NPP satellite captured an image of Hurricane Georgette in the eastern Pacific Ocean that showed an open eye with strong bands of thunderstorms circling the center.
Shortly after Suomi NPP captured the visible image, Georgette's maximum sustained winds had increased to near 130 mph (215 kph) and Georgette became a category 4 hurricane on the Saffir-Simpson Hurricane Wind Scale.
About the same amount of atmospheric carbon that goes into creating plants on land goes into the bodies of tiny marine plants known as plankton. When these plants die and sink, bacteria feed on their sinking corpses and return their carbon to the seawater. When plankton sink deep enough before being eaten, this carbon is taken out of circulation as a greenhouse gas to remain trapped in the deep ocean for centuries.
How much of this happens in different regions of the ocean would seem like an academic question, except during an era when humanity is spewing carbon dioxide into the air at record-high levels and wondering where all that carbon will go in the future.
A University of Washington study published this week (July 25) in the Proceedings of the National Academy of Sciences uses a new approach to get a global picture of the fate of marine carbon. It finds that the polar seas export organic carbon to the deep sea, where it can no longer trap heat from the sun, about five times as efficiently as in other parts of the ocean.
New discoveries about spider silk could inspire novel materials to manipulate sound and heat in the same way semiconducting circuits manipulate electrons, according to scientists at Rice University, in Europe and in Singapore.
A paper in Nature Materials today looks at the microscopic structure of spider silk and reveals unique characteristics in the way it transmits phonons, quasiparticles of sound.
The research shows for the first time that spider silk has a phonon band gap. That means it can block phonon waves in certain frequencies in the same way an electronic band gap - the basic property of semiconducting materials - allows some electrons to pass and stops others.
The researchers wrote that their observation is the first discovery of a "hypersonic phononic band gap in a biological material."
The global economy is becoming less energy intensive, using fewer fossil fuels to power productivity and economic growth, according to new data from the U.S. Department of Energy. Global energy intensity — a measure of energy consumption per unit of gross domestic product (GDP) — has decreased nearly one-third since 1990, the agency said. The U.S., for example, burned 5,900 British thermal units per dollar of GDP in 2015, compared to 6,600 BTUs in 2010.
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