An underground revolution begins this winter.with the flipof a switch,30,000
homes in one part of Detroit will soon become the first in the country to receive electricity transmitted by ice.cold high.performance cables.Other American cities are expected to follow Detroits example in the years ahead.which could conserve enormous amounts of power.
The new electrical cables at the Frisbie power station in Detroit are revolutionary because they are made of superconductors.A superconductor is a material that transmits electricity with little or no resistance.Resistance is the degree to which a substance resists electric current.All common electrical conductors have a certain amount of electrical resistance.They convert at least some of the electrical energy passing through them into waste heat.Superconductors dont?
No one understands how superconductivity works.It just does. Making superconductors isnt easy.A superconductor material has to be cooled to an extremely low temperature to 10se its resistance.The first superconductors,made more than 50 years ago,had to be cooled to -263 degrees Celsius before they lost their resistance.Newer superconducting materials 10se their resistance at -143 degrees Celsius.
The superconductors cable installed at the Frisbie station is made of a ceramic material that contains copper.oxygen.bismuth。strontium。and calcium。A ceramic is a hard.strong compound made from clay or minerals.The superconducting ceramic has been fashioned into a tape that is wrapped lengthwise around a long tube filled with liquid nitrogen.
Liquid nitrogen is super cold and lowers the temperature of the ceramic tape to the point where it conveys electricity with zero resistance.The United States loses an enormous amount of electricity each year to resistance.Because cooled superconductors have no resistance.they waste much less power.0ther cities are watching the Frisbie experiment in the hope that they might switch to superconducting cable and conserve power too.
36 What is the benefit of the revolution mentioned in the first paragraph?
A With a flip of swish.electricity can be transmitted.
B Other American cities can benefit from the high performance cables.
C Great amounts of power can be conserved.
D Detroit will first receive electricity transmitted by the new electrical cables
37 Compared to common electrical conductors,superconductors
A have little or no electrical resistance.
B Can be used for a long time.
C are not energy-efficient.
D can be made easily.
38 At what temperature does the superconducting ceramic lose its resistance?
A -143 degree Celsius.
B -263 degree Celsius.
C As long as it is ice-cold.
D Absolute zero.
39 What element enables the ceramic tape to lower its temperature?
A Copper.
B Liquid nitrogen.
C Clay.
D Calcium.
40 According to the last paragraph,which of the following statements is NOT true?
A Other cities hope they Can also conserve power.
B Other cities hope they Can use superconducting cables soon.
C Superconductors waste less power because of heir low resistance.
D The Frisbie experiment is not successful.
参考答案:C A A B D
美经济不振致“傍大款”名校女生激增
研究称啤酒可防感冒 要大量喝才有效
英年轻人“临终遗愿” 登长城列第四[1]
研究:阅读古典文学可促进大脑发展
有关今生来世的美丽谎言
澳白皮书中文版错误频出 被疑用谷歌翻译
普京命令官员申报个人消费 超出收入部分充公
全球失业率创新高 失业人数达2亿
东京地铁如“通勤地狱”拥挤不堪
闺蜜曝凯特王妃怀孕 将于下月宣布喜讯
英男性对职场超短裙说不 称其太分心
福布斯2017最具权势人物榜 奥巴马登顶
英问题汉堡所含马肉实为波兰廉价碎肉
印度黑公交轮奸案主谋竟是未成年人
习近平在中央政治局常委中外记者见面会上的讲话(双语对照)[1]
奥巴马就职舞会 米歇尔红裙惊艳[1]
奥巴马出访泰国 与总理英拉“打情骂俏”[1]
印度某村禁止女孩穿牛仔裤以免被强奸
俄将在地堡办末日聚会 门票上千美元
美小学枪击案 6岁女童装死逃生
挂牛头卖马肉 千万牛马肉汉堡被召回
全球幸福感排名 拉美第一新加坡垫底
澳总理“力挺”末日论 盼人民战斗到底
意前总理老贝宣布和27岁小女友订婚
贝克汉姆之子罗密欧时尚T台露锋芒
法国封锁
盘点世界各国千奇百怪的迎新年风俗
垃圾收集时限缩短 英国居民被迫早起
俄村庄气温超零下71℃ 获称地球寒极
奥斯卡提名揭晓 《少年派》入围11项
| 不限 |
| 英语教案 |
| 英语课件 |
| 英语试题 |
| 不限 |
| 不限 |
| 上册 |
| 下册 |
| 不限 |