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【简答题】
阅读理解。 A Battery's Nightmare Portable electronics that can be carried about easily are only as good as their batteries (电池) and, let's face it, batteries aren't very good, especially when compared with, say, petrol, which packs 100 times a battery's energy into an equal space. That's why a large group of mechanical engineers (centered at the Massachusetts Institute of Technology, but with partners at other universities and companies) are hard at work in an effort to replace batteries with a tiny engine that runs on fuel. Imagine a battery-free life! When the fuel runs out in your mobile phone, you just fill up and go. The engine-about the size of a ten-cent coin-starts with a combustion chamber (燃烧室) that burns hydrogen. Its tiny parts are etched (蚀刻) onto silicon wafers (硅片) in the same manner that computer parts are etched onto integrated circuits (集成电路). The first engine is made up of five wafers. And since these wafers could be produced in much the same way as computer chips, they could probably be produced quite cheaply. But the devil in all this nice detail is efficiency. Tiny engine parts don't always behave like the bigger parts of the first engine. Something between the parts can slow down the works, according to Columbia University Professor LucFrechette, one of the engine's designers. Extreme heat from the combustion chamber is also a problem, often leaking to other parts of the engine. The scientists' goal is to create an engine that will operate 10 times better than batteries operate. Frechette says that a complete system, with all parts in place and working, will be set up in the next couple of years, but commercial models aren't likely until at least the end of the next ten years. 1. According to the passage, the title suggests that ______. [     ] A. batteries should be greatly improved B. petrol will be used instead of batteries C. the time of batteries will be gone forever D. pollution problems caused by batteries must be solved 2. What's the meaning of the underlined word 'devil' in paragraph 3? [     ] A. Problem B. Advantage C. Invention D. Technique 3. What can we infer from the passage? [     ] A. The new invention doesn't need any fuel. B. The new engine has been produced in large quantities. C. The new invention is much cheaper than the battery. D. The new engine needs to be improved before it's on sale.
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参考答案:
举一反三
【判断题】单叶的叶柄与复叶小叶柄基部均有腋芽
A.
正确
B.
错误
【判断题】为提高焊接效率,采用较大熔深,同时有利于防止气孔和裂纹等缺陷。
A.
正确
B.
错误
【多选题】肿瘤的生长方式包括:
A.
膨胀性生长
B.
浸润性生长
C.
种植性生长
D.
外生性生长
【判断题】用于因子分析的各变量之间的相关系数矩阵中,相关系数都小于0.2,则该数据适合做因子分析
A.
正确
B.
错误
【单选题】We think there was a great deal more diversity in the ( ) native American populations than is apparent today, so this is consistent with a lot of other evidence.
A.
traditional
B.
conventional
C.
original
D.
authentic
【简答题】两腔同时输入压力油,利用 进行工作的 为差动液压缸。它可以实现 的 工作循环。
【单选题】《四世同堂》的分卷名分别是《惶惑》《偷生》( )。
A.
希望
B.
煎熬
C.
胜利
D.
《饥荒》
【简答题】肿瘤的生长方式 包括
【判断题】单叶的叶柄与复叶小叶柄基部均有腋芽。
A.
正确
B.
错误
【多选题】登录环球英语首页后,页面左边可以看到几个大分类分别是什么?
A.
出国英语
B.
学历英语
C.
职业英语
D.
实用英语
E.
小语种
F.
职称英语
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