2015考研英语阅读集中练：Water purification

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考研英语阅读水平的提高重在练习，多练才能够增加词汇量，提升对语法语义的把握，才能够更容易的理解和总结文章中心主旨。正所谓熟能生巧，就是这个道理。十一刚过，后续复习任务依然很重，新东方在线小编希望考生能够继续努力，多读多练。下面分享英语阅读集中练篇章，望考生认真阅读。
    2015考研英语阅读集中练：Water purification
   
    A little-known chemical may provide a new way toclean water
    IRON in water is normally regarded a pollutant.
    Luke Daly, the boss of Ferrate Treatment Technologies of Orlando, Florida,
however, plans toturn that thought on its head.
    He intends to use a chemically unusual form of iron to clean water up, not
make it dirty.
    Iron is found in the part of the periodic table known as the transition
metals.
    Like all metals, these react with other elements by giving up electrons to
form positivelycharged ions.
    Transition metals, though, give updifferent numbers of electrons in
different circumstances, and thus have ions of variouscharges.
    Usually, iron loses two or three electrons.
    But in ferrates, which are compounds of iron and oxygen with non-transition
metals likesodium and calcium, it loses six.
    That makes ferrates extremely reactive, and it is this reactivity which Mr
Daly hopes toexploit.
    First, ferrates are strong oxidising agents.
    That means they destroy bacteria and viruses, and break up organic
molecules withalacrity.
    Second, they are coagulants and flocculating agents.
    They attract other chemicals in the water, including dissolved metals, and
precipitate themfor easy removal.
    Moreover, once it has done its job, the iron in ferrates precipitates too,
as iron oxide, leavingpure water behind.
    The reason these wonder materials have not been used as water purifiers
before is that theirreactivity makes them unstable and thus difficult to
store.
      温馨提示：10月10日，本周五是考研正式报名开始，希望广大应往届考生提前做好准备。
   
   

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