Discovered: A faster way to make biocrude; the most exhaustive bird family tree yet; solar cells made solely from carbon; aphid-resistant raspberries.
Quick-cooked biofuel. Scientists from the U.S. National Research Council recently warned that we switching to algae-derived biofuels at this early stage may incur unsustainable tradeoffs in fertilizer, water, and transportation inputs. They encouraged further research into so-called biocrude though, and may be pleased with the results from a new study by University of Michigan chemical engineer Phil Savage. He's found a way to convert Nannochloropsis alge into fuel in under a minute. The trick is to pack the algae in a steel pipe connector, then submerge it in 1,100-degree Fahrenheit sand. This "pressure cooking" technique really speeds up the process, bringing waits times that were previously up to 90 minutes down to 60 seconds. "By reducing the reactor volume, the cost of building a biocrude production plant also decreases," says co-researcher Julia Faeth, giving hope for companies that want to mass produce biocrude sustainably. [Univeristy of Michigan]
Black raspberries that can withstand aphid attacks. Those of you partial to the red raspberry's moodier sibling will be happy to hear that USDA researchers have discovered black raspberries that are naturally resistant to aphids. Researchers led by the USDA Agricultural Research Service's Chad Finn studied samples from 132 wild black raspberry patches, finding natural genetic resistance to the black raspberry aphid in berries from Ontario, Maine, and Michigan. These findings will help growers halt the spread of black raspberry necrosis virus, which is carried by the aphids. "This is the first report of aphid resistance in black raspberry," the USDA reports. [USDA Agricultural Research Service]
Mapping the bird kingdom to plot avian evolution. There are almost 10,000 different species of bird in existence today. So scientists led by Yale University's Walter Jetz had their work cut out for them when they set out to create a comprehensive family tree of every living type of bird. But they did it, finding that evolutionary diversification has sped up over the last 50 million years. That's an unexpected finding, says co-author Arne Mooers of Simon Fraser University in Canada. "The current zeitgeist in biodiversity science is that the world can fill up quickly," she says. "These species fill up all the available niches, and then there is nowhere to go. Extinction catches up, and things begin to slow down or stall. For birds the pattern is the opposite: Speciation is actually speeding up, not slowing down." [Yale University]
An all-carbon solar cell. Typical solar power technology relies on expensive synthetic materials. If you have a solar panel installed on your roof it's probably made with silicon, for instance. But Stanford University chemical engineering professor Zhenan Bao thought she could simplify and green these designs, so she and her colleagues made an entirely carbon-based solar cell. "Carbon has the potential to deliver high performance at a low cost," says Bao. "To the best of our knowledge, this is the first demonstration of a working solar cell that has all of the components made of carbon." The solar cells place a photoactive layer between two graphene electrodes, making the final product so thin and flexible that they hope it will coat walls and windows in future buildings. [Stanford University]