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Sugar Power for Cell Phones In fuel cells，chemical reactions generate electrical currents.The process usually relies on precious metals，such as platinum.In living cells，enzymes perform a similar job，breaking down sugars to obtain electrons and produce energy. Minteer and Tamara Klotzbach，also of St Louis University，have now developed polymers that wrap around an enzyme and preserve it in a microscopic pocket.We tailor these pockets to provide the ideal microenvironment for the enzyme，Minteer says.The polymers keep the enzyme active for months instead of days. So far，the new fuel cells dont produce much power，but the fact that they work at all is exciting，says Paul Kenis，a chemical engineer at the University of Illinois2 at Urhana-Champaign3.Just getting it to work. Kenis says，is a major accomplishment. 试题 A When enzymes can be commonly found in living ceils. C When the technology of a new type of fuel cell is suitable for mass production. 1. What trouble did Minteer and Klotzhach have in their research? B They had trouble keeping biological cells active. D They had trouble finding mechanism for producing enzymes. A when bags of enzyme are embedded in the new fuel cell. C when the enzyme oxidizes the glucose from a sugary liquid that goes through a pocket. 2. What is exciting about the new fuel cells? B Their limited power generation capacity is a good beginning. D Their limitless power generation capacity is a major accomplishment, A The new fuel cells run on sugar that is easy to find. C The new fuel cells are biologically degradable, 答案与题解： 1. C A和D明显不是正确答案。B不是正确选择，因为只有当这种新的燃料电池被大规模生产时，才有可能实现用甜饮料给手机提供电能。 2. C 该段第二句When glucose from a sugary liquid penetrates a pocket，the enzyme oxidizes it，releasing electrons and proton中的it指代glucose，而不是a sugary liquid，因 此C是正确选择。 3. D 文章的最后一段指出了这种新型燃料电池的优点，即A、B、C所述内容。最后一句说，科学家预计，在不到三年的时间里这种新技术便可在大众的流行产品中使用。所以D是正确选择。 | 
