2017年雅思阅读考试模拟题.docVIP

2017年雅思阅读考试模拟题 　　目标既定，在学习和实践过程中无论遇到什么困难、曲折都不灰心丧气，不轻易改变自己决定的目标，而努力不懈地去学习和奋斗，如此才会有所成就，而达到自己的目的。以下是小编为大家有哪些信誉好的足球投注网站整理的2017年雅思阅读考试模拟题，希望对正在关注的您有所帮助!更多精彩内容请及时关注我们应届毕业生! 　　Dec 13th 2017 　　From The Economist print edition 　　1 REFRIGERATORS are the epitome of clunky technology: solid, reliable and just a little bit dull. They have not changed much over the past century, but then they have not needed to. They are based on a robust and effective idea--draw heat from the thing you want to cool by evaporating a liquid next to it, and then dump that heat by pumping the vapour elsewhere and condensing it. This method of pumping heat from one place to another served mankind well when refrigerators#39; main jobs were preserving food and, as air conditioners, cooling buildings. Today#39;s high-tech world, however, demands high-tech refrigeration. Heat pumps are no longer up to the job. The search is on for something to replace them. 　　2 One set of candidates are known as paraelectric materials. These act like batteries when they undergo a temperature change: attach electrodes to them and they generate a current. This effect is used in infra-red cameras. An array of tiny pieces of paraelectric material can sense the heat radiated by, for example, a person, and the pattern of the array#39;s electrical outputs can then be used to construct an image. But until recently no one had bothered much with the inverse of this process. That inverse exists, however. Apply an appropriate current to a paraelectric material and it will cool down. 　　3 Someone who is looking at this inverse effect is Alex Mischenko, of Cambridge University. Using commercially available paraelectric film, he and his colleagues have generated temperature drops five times bigger than any previously recorded. That may be enough to change the phenomenon from a laboratory curiosity to something with commercial applications. 　　4 As to what those applications might be, Dr Mischenko is still a little hazy. He has, nevertheless, set up