Sugar Power for Cell Phones

　　Using enzymes commonly found in living cells，a new type of fuel cell produces small amounts of electricity from sugar.If the technology is able to succeed in mass production，you may some day share your sweet drinks with your cell phone.

　　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.

　　When researchers previously used enzymes in fuel cells，they had trouble keeping them active，says Shelley D.Minteer of St Louis University1.Whereas biological cells continually produce fresh enzymes，there’s no mechanism in fuel cells to replace enzymes as they quickly degrade.

　　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

　　In the new fuel Cell，tiny polymer bags of enzyme are embedded in a membrane that coats one of the electrodes.When glucose from a sugary liquid gets into a pocket，the enzyme oxidizes it，releasing electrons and protons.The electrons cross the membrane and enter a wire through which they travel to the other electrode，where they react with.oxygen in the atmosphere to produce water.The flow of electrons through the wire constitutes an electrical current that can generate power.

　　So far，the new fuel cells don’t 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.”

　　Sugar-eating fuel cells could be an efficient way to make electricity.Sugar is easy to find. And the new fuel cells that run on it are biodegradable，so the technology wouldn’t hurt the environment.The scientists are now trying to use different enzymes that will get more power from sugar.They predict that popular products may be using the new technology in as little as 3 years.

　　詞匯：

　　enzyme/5enzaIm/n.酶 electrode/I5lektrEJd/n.電極platinum/5plAtinEm/n.鉑，白金 membrane/5membrein/n.膜，薄膜

　　electron/I5lektrRn/n.電子 oxidize/5Cksi7daiz/v.氧化degrade/di5reid/v.降解 glucose/5lu:kEus/n.葡萄糖

　　polymer/5pClimE/n.聚合物 biodegradable/7baiEudi5reidEbl/adj.能進(jìn)行生物降解的

　　microenvironment n.微環(huán)境 embed/im5bed/v.埋置，插入

　　proton/5prEutCn/n.質(zhì)子

　　試題

　　1. According to the first paragraph，when can we share our sweet drinks with our cell phones?

　　A When enzymes can be commonly found in living ceils.

　　B When the technology of producing a new type of fuel cell appears.

　　C When the technology of a new type of fuel cell is suitable for mass production.

　　D When the technology of mass producing cell phones appears.

　　2. What trouble did Minteer and Klotzhach have in their research?

　　A They had trouble keeping enzymes in fuel cells active.

　　B They had trouble keeping biological cells active.

　　C They had trouble producing fresh enzymes.

　　D They had trouble finding mechanism for producing enzymes.

　　3. According to Paragraph 5，electrons are released

　　A when bags of enzyme are embedded in the new fuel cell.

　　B when glucose from a sugary liquid goes through the enzyme.

　　C when the enzyme oxidizes the glucose from a sugary liquid that goes through a pocket.

　　D when the enzyme oxidizes the sugary liquid that goes through a pocket.

　　4. What is exciting about the new fuel cells?

　　A Their limitless power generation capacity is amazing.

　　B Their limited power generation capacity is a good beginning.

　　C Their limited power generation capacity is the result of great efforts.

　　D Their limitless power generation capacity is a major accomplishment,

　　5. According to the last paragraph，what is NOT true of the new fuel cells?

　　A The new fuel cells run on sugar that is easy to find.

　　B The new fuel cells are environment friendly.

　　C The new fuel cells are biologically degradable,

　　D It will take some time before the new fuel cells can be used in popular products.

　　答案與題解：

　　1. C A和D明顯不是正確答案。B不是正確選擇，因?yàn)橹挥挟?dāng)這種新的燃料電池被大規(guī)模生產(chǎn)時(shí)，才有可能實(shí)現(xiàn)用甜飲料給手機(jī)提供電能。

　　2. A 文章第三段的第一句是問(wèn)題的答案。

　　3. C 該段第二句“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是正確選擇。

　　4. B 第六段的大意是，盡管這種新型燃料電池還不能產(chǎn)牛很多電能，但是，它能夠產(chǎn)生電能的事實(shí)就已經(jīng)是很大的成就了。因而激動(dòng)人心。所以只有B是正確答案。

　　5. D 文章的最后一段指出了這種新型燃料電池的優(yōu)點(diǎn)，即A、B、C所述內(nèi)容。最后一句說(shuō)，科學(xué)家預(yù)計(jì)，在不到三年的時(shí)間里這種新技術(shù)便可在大眾的流行產(chǎn)品中使用。所以D是正確選擇