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雅思阅读模拟练习题及解析

摘要：

雅思模拟试题在雅思备考过程中所起的作用不可小觑，通过模拟练习题，我们可以很直接地了解到自己的备考状况，从而可以更有针对性地进行之后的复习。希望以下内容能够对大家的雅思备考有所帮助!

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' main jobs were preserving food and, as air conditioners, cooling buildings. Today'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'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.