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科目:高中英語 來源:山東省高考真題 題型:閱讀理解
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 / nanoelectromechanreal 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 (半導(dǎo)體). 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 (晶體結(jié)構(gòu)) of the solid semiconductor," Kwon said, "By using a liquid semicon
ductor, 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.
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科目:高中英語 來源:0123 期末題 題型:閱讀理解
閱讀理解。 | ||
Below is adapted from an English dictionary.
| ||
1. I didn't really mean my partner is a snake; it was just a _____. | ||
[ ] | ||
A. figure of eight B. figure head C. figure of speech D. a fine figure | ||
2. — She was coming late again. — _____! That's typical of her. | ||
[ ] | ||
A. It figures her out B. It figures C. It cuts a poor figure D. She is a figure of fun | ||
3. What does "watch my figure" in the sentence "Don't tempt me with chocolate; I am watching my figure." mean? | ||
[ ] | ||
A. add the numbers B. have sports C. try not to get fat D. watch games |
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科目:高中英語 來源:0124 月考題 題型:閱讀理解
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科目:高中英語 來源:期中題 題型:閱讀理解
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科目:高中英語 來源:0117 期中題 題型:閱讀理解
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科目:高中英語 來源:0103 月考題 題型:閱讀理解
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科目:高中英語 來源:山東省期末題 題型:閱讀理解
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科目:高中英語 來源:吉林省期中題 題型:閱讀理解
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