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Although the Amazon Jungle may appear to be perpetually green, a University of Illinois researcher believes there are actually seasonal differences of photosynthesis, with more occurring during the dry season and less during the wet season. Understanding how a rainforest that occupies 2.7 million square miles of South America functions is crucial to the future health of the entire planet.

"With the potential negative effects of climate change, one key question we are trying to answer in the study of tropical ecology is how a tropical forest responds during a long-term drought," says Kaiyu Guan, an environmental scientist at the University of Illinois. "If we don't know their daily performance or their seasonal performance, what confidence can we have to predict the forests' future 20 years, 30 years, or longer?"

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.

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.

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.

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.