2016年ietls雅思阅读模拟试题（9）_第2页

　　8 The trick to a good thermoelectric material is a crystal structure in which electrons can flow freely, but the path of phonons--heat-carrying vibrations that are larger than electrons--is constantly interrupted.In practice, this trick is hard to pull off, and thermoelectric materials are thus less efficient than paraelectric ones (or, at least, than those examined by Dr Mischenko).Nevertheless, Rama Venkatasubramanian, of Nextreme Thermal Solutions in North Carolina, claims to have made thermoelectric refrigerators that can sit on the back of computer chips and cool hotspots by 10℃.Ali Shakouri, of the University of California, Santa Cruz, says his are even smaller--so small that they can go inside the chip.

　　9 The last word in computer cooling, though, may go to a system even less techy than a heat pump--a miniature version of a car radiator.Last year Apple launched a personal computer that is cooled by liquid that is pumped through little channels in the processor, and thence to a radiator, where it gives up its heat to the atmosphere.To improve on this, IBM's research laboratory in Zurich is experimenting with tiny jets that stir the liquid up and thus make sure all of it eventually touches the outside of the channel--the part where the heat exchange takes place.In the future, therefore, a combination of microchannels and either thermoelectrics or paraelectrics might cool computers.The old, as it were, hand in hand with the new.

　　(830 words)

　　Questions 1-5

　　Complete each of the following statements with the scientist or company name from the box below.

　　Write the appropriate letters A-F in boxes 1-5 on your answer sheet.

　　A. Apple

　　B. IBM

　　C. Intel

　　D. Alex Mischenko

　　E. Ali Shakouri

　　F. Rama Venkatasubramanian

　　1....and his research group use paraelectric film available from the market to produce cooling.

　　2....sold microprocessors running at 60m cycles a second in 1993.

　　3....says that he has made refrigerators which can cool the hotspots of computer chips by 10℃.

　　4....claims to have made a refrigerator small enough to be built into a computer chip.

　　5....attempts to produce better cooling in personal computers by stirring up liquid with tiny jets to make sure maximum heat exchange.