【英语时差8,16】蓝细菌:未来的燃料(上)(在线收听) |
When most people fill their gas tanks, they think of fossil fuels and pumping oil from the ground. But many scientists around the country think bacteria. Bacteria have a bad reputation because they are responsible for several human illnesses, but there are many thousands of species of bacteria. Some of the most interesting species are cyanobacteria which used to be called blue green algae because of their color. These bacteria are naturally found in bodies of water, and like plants, use sunlight to convert carbon dioxide into energy. Currently, we are using plants like corn to produce ethanol. It is a time consuming, expensive process that involves growing plants, transporting them, fermenting and processing them to get fuel. With bacteria, carbon dioxide can be converted directly into organic chemicals. The only problem has been the quantity and type of fuels bacteria can produce. |
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