摘要:5.试卷结构 (1)试卷结构汇总表 主.客观题权重 知识.能力题权重 能力层次权重 难度 主观 客观 知识 能力 理解 简单应用 综合运用 控制 开放 ≤0.30 ≥0.10 ≤0.60 ≤0.20 ≥ 0.80 0.40 0.25 0.35 0.80~0.85 (2)试卷结构细目表 注:表中“简单 全称是“简单应用 .“综合 全称是“综合运用 .

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Batteries can power anything from small sensors to large systems.While scientists are finding ways to make them smaller but even more powerful, problems can arise when these batteries are much larger and heavier than the devices themselves.University of Missouri(MU) researchers are developing a nuclear energy source that is smaller, lighter and more efficient.
“To provide enough power, we need certain methods with high energy density(密度)”,said Jae Kwon, assistant professor of electrical and computer engineering at MU.“The radioisotope(放射性同位素) battery can provide power density that is much higher than chemical batteries.”
Kwon and his research team have been working on building a small nuclear battery, presently the size and thickness of a penny, intended to power various micro / nanoelectromechanical systems (M/NEMS).Although nuclear batteries can cause concerns, Kwon said they are safe.
“People hear the word ‘nuclear’ and think of something very dangerous,” he said, “However, nuclear power sources have already been safely powering a variety of devices, such as pace-makers, space satellites and underwater systems.”
His new idea is not only in the battery’s size, but also in its semiconductor(半导体).Kwon’s battery uses a liquid semiconductor rather than a solid semiconductor.
“The key part of using a radioactive battery is that when you harvest the energy, part of the radiation energy can damage the lattice structure(晶体结构) of the solid semiconductor,” Kwon said, “By using a liquid semiconductor, we believe we can minimize that problem.”
Together with J.David Robertson, chemistry professor and associate director of the MU Research Reactor, Kwon is working to build and test the battery.In the future, they hope to increase the battery’s power, shrink its size and try with various other materials.Kwon said that battery could be thinner than the thickness of human hair

  1. 1.

    The text is most probably a ______.

    1. A.
      science news report
    2. B.
      book review
    3. C.
      newspaper ad
    4. D.
      science fiction
  2. 2.

    Liquid semiconductor is used to ______.

    1. A.
      get rid of the radioactive waste
    2. B.
      test the power of nuclear batteries
    3. C.
      decrease the size of nuclear batteries
    4. D.
      reduce the damage to lattice structure
  3. 3.

    According to Jae Kwon, his nuclear battery ______.

    1. A.
      uses a solid semiconductor
    2. B.
      will soon replace the present ones
    3. C.
      could be extremely thin
    4. D.
      has passed the final test
  4. 4.

    Jae Kwon gave examples in Paragraph 4______.

    1. A.
      to show chemical batteries are widely applied
    2. B.
      to introduce nuclear batteries can be safely used
    3. C.
      to describe a nuclear-powered system
    4. D.
      to introduce various energy sources
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It was a winter morning, just before Christmas, while most people were warming up their cars, my husband, Trevor, had to ride his bike 4 kilometers away from home to work. On his  【小题1】  (arrive), he parked his bike outside the back door  【小题2】 usual. After 10 hours of labor, he returned to find his bike gone, 【小题3】  was our only transport. Trevor used it to get to work, and also the bike was used  【小题4】  (get) groceries, saving us from having to walk long distances from  【小题5】 we live.
I was so sad that I wrote to the newspaper and told【小题6】 our story. Shortly after that, several people in our area offered to help. One wonderful stranger even bought a bike, and then called my husband to fetch it. Once again my husband had a way to get to and   【小题7】 his job. It really is   【小题8】 honor that a complete stranger would go out of their way for someone they have never met before.
People say that a smile can   【小题9】  (pass) from one person to another, but acts of kindness from strangers are even more so. This experience has had a spreading effect in our lives because it  【小题10】   (strong) our faith in humanity. And it has influenced us to be more mindful of ways, we, too, can share with others.

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