______ Chemistry is a branch of Chemistry.
A.ApplyingB.Apply C.AppliedD.Applicant
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科目:高中英語 來源: 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 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, recently the size and thickness of a penny, intended to power various micro/nano-electromechanical systems (M/NEWS). 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 (晶格結(jié)構(gòu)) 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 the battery could be thinner than the thickness of human hair.
Which of the following is true of Jae Kwon?
A. He teaches chemistry at MU.
B. He developed a chemical battery.
C. He is working on a nuclear energy source.
D. He made a breakthrough in computer engineering.
Jae Kwon gave examples in Paragraph 4 ________.
A. to show chemical batteries are widely applied
B. to indicate nuclear batteries can be safely used
C. to describe a nuclear-powered system
D. to introduce various energy sources.
Liquid semiconductor is used to ________ .
A. get rid of the radioactive waste
B. test the power of nuclear batteries
C. decrease the size of nuclear batteries
D. reduce the damage to lattice structure
According to Jae Kwon, his nuclear battery ________.
A. uses a solid semiconductor B. will soon replace the present ones
C. could be extremely thin D. has passed the final test
The text is most probably a ________.
A. science news report B. book review
C. newspaper ad D. science fiction story
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科目:高中英語 來源:2015屆云南楚雄州武定縣第一中學(xué)高一下期期中考試英語卷(解析版) 題型:閱讀理解
Science, as we think, was born when the Greek philosopher ( 希臘哲學(xué)家 ) Thales ( about 640-546 B.C.) asked a difficult question: What makes up our universe?
No one had a ready answer, so Thales went on studying the earth around him, the sky and the stars. He saw so much water on earth and so much water falling from the sky as rain that he decided water must be the basic substance ( 物質(zhì) ) of the universe.
Other Greek thinkers became interested in this question. They suggested other answers. One said that because air lies around the earth, it must be air that makes up all things. Another said that fire, appearing in different forms, was the building block of the universe.
The Greek philosophers were feeling their way towards the ideas on which chemistry is based. Centuries later, scientists proved that the universe is made up of certain basic substances. But the list is much more complicated than the Greeks realized. We now know of 103 basic substances which we call “ elements ( 元素 )”.
1.Thales, the famous Greek philosopher, died when he was about _________.
A.106 years old B.94years old C.64 years old D.46 years old
2.From the passage we know that __________.
A.Thales asked many questions B.Greeks were all philosophers
C.science began long ago D.water and air make up all things.
3.After reading the passage, we can be sure that_________.
A.nothing ever changes in the universe
B.Thales decided that the basic substance of the universe was air
C.the universe is made up of four different substances
D.the early Greek thinkers did much valuable work for the progress of science
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科目:高中英語 來源:2011-2012學(xué)年黑龍江省哈爾濱市高三第二次模擬考試英語試卷(解析版) 題型:短文改錯(cuò)
假定英語課上英語老師要求同桌之間互相修改作文,請(qǐng)你修改你同桌的以下作文。
文中共有10處語言錯(cuò)誤,每句中最多有兩處。錯(cuò)誤涉及一個(gè)單詞的增加、刪除或修改。
刪除:把多余的詞用斜線(\)劃掉。
增加:在缺詞處加一個(gè)漏字符號(hào)(∧),并在該詞下面寫出該加的詞。
修改:在錯(cuò)的詞下劃一橫線,在該詞下面寫出修改后的詞。
注意:1、每處錯(cuò)誤及修改均僅限一詞。
2、只允許修改10處,多者(從11處起)不計(jì)分。
Boys and girls, welcome to Elite Secondary School! I’m Mr. Green, in charge of this school. I’d like to introduce you to various aspect of our school, from our history to our buildings and activities. Elite Secondary School set up in 1960. In the past fifty years, Elite had experienced a lot of changes and developments. Our school finally decided to move to Aberdeen in 1990, due to the lack of the space. The school campus now was almost three times larger than the previous one. We even have three libraries which are available with all the teachers and students. As for laboratories, they have two Physics labs, two Chemistry labs, and a Biology lab which was established last year. Students here always have an enjoyable time at school because there is a widely range of extra-curricular activities for them to choose. We try to provide as much activities for our students as possible. Elite Secondary School is committed to providing the highest level of education to the children. Thank you for your time.
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科目:高中英語 來源:2011-2012學(xué)年浙江省高三第一學(xué)期第一次統(tǒng)練英語試題 題型:完型填空
I lived in Dallas, Texas nearly all my life with my mom, dad and older sister. We were 41 to respect others, value education, and get all that we could out of life. My parents always say, “ 42 hard and the world is yours.” They are never without a 43 word of advice or a bit of encouragement when life gets tough.
My parents always 44 me to go to college. However, when I 45 at 16 years old that I’d rather get married to a man than go to college, they 46 stopped telling me they loved me and I could anything I wanted to. 47 , they persuaded me. I graduated from high school and currently 48 the University of Oklahoma studying medicine. I want to make the 49 a better place to live in.
Every time I call home to tell them about a 50 I received in Chemistry Lab or Microeconomics or whichever 51 it is that I’m working hardest for at the moment, they tell me how 52 of me they are. I know there are college kids out there that have no one to call home when they an “A” on a project and I feel incredibly 53 to have my parents.
Don’t get me wrong: We’ve had our share of 54 . I was the angry teenager and they were the awful 55 that wouldn’t let me stay out all night or let me get my tongue pierced(扎洞).But somehow, we 56 to work through those issues. They never 57 loving in me or believing in me.
I 58 everything I am to my parents. Without their 59 love and encouragement, I wouldn’t believe I can change the world. My parents taught me to always 60 for what I believe in. So I’m working toward something really great and can only hope I continue to make them proud.
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科目:高中英語 來源:2011年安徽省同心圓夢(mèng)高三模擬試卷英語(解析版) 題型:單項(xiàng)填空
— Can you tell me something about _________ science.
— OK. _ Nobel Prize in Chemistry is usually awarded to Americans.
A.the; The |
B./; The |
C.a(chǎn); / |
D.the; / |
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