欢迎来到天天文库
浏览记录
ID:26134347
大小:32.03 KB
页数:15页
时间:2018-11-25
《2012年职称英语《理工类》阅读理解练习题》由会员上传分享,免费在线阅读,更多相关内容在教育资源-天天文库。
1、2012年职称英语《理工类》阅读理解练习题(1)ElectricBackpack Backpacksareconvenient.Theycanholdyourbooks,yourlunch,andachangeofclothes,leavingyourhandsfreetodootherthings.Someday,ifyoudon'tmindcarryingaheavyload,yourbackpacksmightalsopoweryourMP31player,keepyourcellphonerunning,andmaybeevenlightyourwayhome
2、. LawrenceC.RomeandhiscolleaguesfromtheUniversityofPennsylvaniainPhiladelphia2andtheMarineBiologicalLaboratoryinWoodsHole3,Mass.4,haveinventedabackpackthatmakeselectricityfromenergyproducedwhileitswearerwalks.Inmilitaryactions,search-and-rescueoperations,andscientificfieldstudies,people
3、relyincreasinglyoncellphones,globalpositioningsystem(GPS)5receivers,night-visiongoggles,andotherbatterypowereddevicestogetaroundanddotheirwork.Thebackpack’selectricity-generatingfeaturecoulddramaticallyreducetheamountofawearer’sloadnowdevotedtosparebatteries,reportRomeandhiscolleaguesint
4、heSept.9Science6. Thebackpack’selectricity-creatingpowersdependonspringsusedtohangaclothpackfromitsmetalframe.Theframesitsagainstthewearer’sback,andthewholepackmovesupanddownasthepersonwalks.Agearmechanismconvertsverticalmovementsofthepacktorotarymotionsofanelectricalgenerator,producing
5、upto7.4watts. Unexpectedly,testsshowedthatwearersofthenewbackpackaltertheirgaitsinresponsetothepack’soscillations,sothattheycarryloadsmorecomfortablyandwithlesseffortthantheydoordinarybackpacks.Becauseofthatsurprisingadvantage,Romeplanstocommercializebothelectricandnon-electricversionso
6、fthebackpack. Thebackpackcouldbeespeciallyusefulforsoldiers,scientists,mountaineers,andemergencyworkerswhotypicallycarryheavybackpacks.Fortherestofus,power-generatingbackpackscouldmakeitpossibletowalk,playvideogames,watchTV,andlistentomusic,allatthesametime.Electricity-generatingpacksar
7、en’tonthemarketyet,butifyoudogetoneeventually,justmakesuretolookbothwaysbeforecrossingthestreet! 相关词汇: backpack/5bAkpAk/n.背包watt/wCt/n.瓦(特) receiver/ri5si:vE(r)/n.接收机gait/eit/n.步态,步法 night-visiongoggle夜视镜oscillation/7Csi5leiFEn/n.摆动 spring/spriN/n.弹簧commercialize/kE5
此文档下载收益归作者所有