久久一区二区三区精品-久久一区二区明星换脸-久久一区二区精品-久久一区不卡中文字幕-91精品国产爱久久久久久-91精品国产福利尤物免费

職稱英語考試理工類閱讀理解專項訓練

雕龍文庫 分享 時間: 收藏本文

職稱英語考試理工類閱讀理解專項訓練

  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.  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,theres no mechanism in fuel cells to replace enzymes as they quickly degrade.  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.  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 wouldnt 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.  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.  2. 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  D when the enzyme oxidizes the sugary liquid that goes through a pocket.  A Their limitless power generation capacity is amazing.  C Their limited power generation capacity is the result of great efforts.  5. According to the last paragraph,what is NOT true of the new fuel cells?  B The new fuel cells are environment friendly.  D It will take some time before the new fuel cells can be used in popular products.

  

  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.  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,theres no mechanism in fuel cells to replace enzymes as they quickly degrade.  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.  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 wouldnt 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.  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.  2. 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  D when the enzyme oxidizes the sugary liquid that goes through a pocket.  A Their limitless power generation capacity is amazing.  C Their limited power generation capacity is the result of great efforts.  5. According to the last paragraph,what is NOT true of the new fuel cells?  B The new fuel cells are environment friendly.  D It will take some time before the new fuel cells can be used in popular products.

  

主站蜘蛛池模板: 国产成人福利夜色影视 | 亚洲精品国产综合一线久久 | 日本三级s级在线播放 | 99pao在线视频成精品 | freesexvideo性欧美tv2021 | 久久精品亚洲 | 99久久国产综合精品国 | 亚洲国产第一区二区香蕉日日 | 久久毛片免费看一区二区三区 | 九九精品99久久久香蕉 | 风流慈禧一级毛片在线播放 | 成人免费看片 | 亚洲国产天堂久久九九九 | 久久道| 中文字幕播放 | 国产看片视频 | 国内精品美女写真视频 | 日韩中文字幕精品久久 | 欧美激情久久久久久久久 | 精品久久久久国产 | 91精品福利手机国产在线 | 欧美亚洲网站 | 女人张开腿 让男人桶视频 女人张开腿等男人桶免费视频 | 在线看片一区 | 成人在线免费观看视频 | 欧美久久久久久久久 | 又刺激又黄的一级毛片 | 日韩成人小视频 | 久久视频免费 | 在线亚洲精品视频 | 亚洲操综合 | 欧美 自拍 丝袜 亚洲 | 99视频在线观看视频一区 | 久在草视频 | 欧美精品亚洲精品日韩一区 | 呦视频在线一区二区三区 | 欧美精品一区二区精品久久 | 免费看欧美一级片 | 中国一级毛片录像 | 日本红怡院亚洲红怡院最新 | 国产日韩欧美一区二区三区在线 |