名词解释：变压器-查字典考试网

你可能感兴趣的试题

绝缘手套的测验周期是（）。

A、每年一次
B、六个月一次
C、五个月一次

查看答案

绝缘靴的试验周期是（）。

A、每年一次
B、六个月一次
C、三个月一次

查看答案

能实现“有0出1，全1出0”逻辑功能是____电路。

查看答案

晶闸管的阻断作用有

A、正向阻断
B、反向阻断
C、正向偏置
D、反向偏置
E、门极偏置

查看答案

PLC输出点类型的有主要有哪些（）。

A、继电器
B、可控硅
C、晶体管
D、IC驱动电路
E、二极管

查看答案

热门试题更多>

PARTVREADINGCOMPREHENSION Inthissectiontherearefourpassagesfollowedbyquestionsorunfinishedstatements,eachwithfoursuggestedanswersmarkedA,B,CandD.Choosetheonethatyouthinkisthebestanswer. TEXTA Racket,dinclamor,noise,whateveryouwanttocallit,unwantedsoundisAmerica'smostwidespread nuisance.Butnoiseismorethanjustanuisance.Itconstitutesarealandpresentdangertopeople'shealth.Day andnight,athome,atwork,andatplay,noisecanproduceseriousphysicalandpsychologicalstress.Nooneis immunetothisstress.Thoughweseemtoadjusttonoisebyignoringit,theear,infact,neverclosesandthe bodystillresponds—sometimeswithextremetension,astoastrangesoundinthenight. Theannoyancewefeelwhenfacedwithnoiseisthemostcommonoutwardsymptomofthestressbuilding upinsideus.Indeed,becauseirritabilityissoapparent,legislatorshavemadepublicannoyancethebasisof manynoiseabatementprograms.Themoresubtleandmoreserioushealthhazardsassociatedwithstress causedbynoisetraditionallyhavebeengivenmuchlessattention.Nevertheless,whenweareannoyedormade irritablebynoise,weshouldconsiderthesesymptomsfairwarningthatotherthingmaybehappeningtous, someofwhichmaybedamagingtoourhealth. Ofmanyhealthhazardstonoise,hearinglossisthemostclearlyobservableandmeasurablebyhealth professionals.Theotherhazardsarehardertopindown.Formanyofus,theremaybeariskthatexposuretothe stressofnoiseincreasessusceptibilitytodiseaseandinfection.Themoresusceptibleamongusmayexperience noiseasacomplicatingfactorinheartproblemsandotherdiseases.Noisethatcausesannoyanceandirritability inhealthpersonsmayhaveseriousconsequencesforthesealreadyillinmindorbody. Noiseaffectsusthroughoutourlives.Forexample,thereareindicationsofeffectsontheunbornchildwhen mothersareexposedtoindustrialandenvironmentalnoise.Duringinfancyandchildhood,youngstersexposed tohighnoiselevelsmayhavetroublefallingasleepandobtainingnecessaryamountsofrest. Why,then,istherenotgreateralarmaboutthesedangers?Perhapsitisbecausethelinkbetweennoiseand manydisabilitiesordiseaseshasnotyetbeenconclusivelydemonstrated.Perhapsitisbecausewetendto dismissannoyanceasapricetopayforlivinginthemodernworld.Itmayalsobebecausewestillthinkof hearinglossasonlyanoccupationalhazard. 1.InParagraph1,thephrase"immuneto"areusedtomean___. A.unaffectedby B.hurtby C.unlikelytobeseenby D.unknownby 2.Theauthor'sattitudetowardnoisewouldbestbedescribedas___. A.unrealistic B.traditional C.concerned D.hysterical 3.Whichofthefollowingbeststatesthemainideaofthepassage? A.Noiseisamajorproblem;mostpeoplerecognizeitsimportance. B.Althoughnoisecanbeannoying,itisnotamajorproblem. C.Noiseisamajorproblemandhasnotyetbeenrecognizedassuch. D.Noiseisamajorproblemaboutwhichnothingcanbedone. 4.Theauthorcondemnsnoiseessentiallybecauseit___. A.isagainstthelaw B.canmakesomepeopleirritable C.isanuisance D.inagangertopeople'shealth 5.Theauthorwouldprobablyconsiderresearchabouttheeffectsnoisehasonpeopletobe___. A.unimportant B.impossible. C.awasteofmoney D.essential
PartIIICloze Directions:Therearetwentyblanksinthefollowingpassage.Foreachblanktherearefourchoices.ChoosetheonethatbestfitsintothepassageandthenmarksyouranswerontheAnswerSheet. Therearetwofactorswhichdetermineanindividual’sintelligence.Thefirstisthesortofbrainheisborn61.Humanbrainsdifferconsiderably,62beingmorecapablethanothers.63nomatterhowgoodabrainhehastobeginwith,anindividualwillhavealoworderofintelligence64hehasopportunitiestolearn.Sothesecondfactoriswhat65totheindividual—thesortofenvironmentinwhichheisbrought66.Ifanindividualishandicapped(受阻碍)67,itislikelythathisbrainwill68todevelopandhewill69attainthelevelofintelligenceofwhichheis70. Theimportanceofenvironmentindetermininganindividual’sintelligencecanbe71bythecasehistoryoftheidenticaltwins,PeterandJohn.Whenthetwinswerethreemonthsold,theirparentsdied,andtheyareplacedin72foster(寄养)homes.Peterwasrearedbyparentsoflowintelligenceinan73communitywithpooreducational74.John,75,waseducatedinthehomeofwell-to-doparentswhohasbeentocollege.Thisenvironmental76continueduntilthetwinswere77theirlateteens,78theyweregiventeststo79theirintelligence.John’sI.Q.(智商)was125,twenty-fivepointshigherthanthe80andfullyfortypointshigherthanhisidenticalbrother. 61.A.forB.byC.withD.in 62.A.mostB.someC.manyD.few 63.A.ButB.ForC.StillD.And 64.A.ifB.thoughtC.asD.unless 65.A.refersB.appliesC.happensD.concerns 66.A.aboutB.upC.forwardD.forth 67.A.relativelyB.intelligentlyC.regularlyD.environmentally 68.A.failB.helpC.manageD.stop 69.A.everB.neverC.evenD.nearly 70.A.ableB.capableC.availableD.acceptable 71.A.demonstratedB.deniedC.neglectedD.ignored 72.A.separateB.similarC.remoteD.individual 73.A.omittedB.isolatedC.enclosedD.occupied 74.A.possibilitiesB.opportunitiesC.capacitiesD.responsibilities 75.A.moreoverB.consequentlyC.thenD.however 76.A.exceptionB.divisionC.differenceD.alteration 77.A.inB.byC.atC.for 78.A.whileB.sinceC.whenD.because 79.A.estimateB.countC.decideD.measure 80.A.averageB.commonC.usualD.ordinary
有人经常跳槽或换岗位，你怎么看待?
一天，张主任和刘主任每人交给你一项任务，但是你忙了一天，结果只完成了一项。刘主任把你批评了一通，你怎么想?怎么做?
Wecanbeginourdiscussionof“populationasglobalissue”withwhatmostpersonsmeanwhentheydiscuss“thepopulationproblem”:toomanypeopleonearthandatoorapidincreaseinthenumberaddedeachyear.Thefactsarenotindispute,Itwasquiterighttoemploytheanalogythatlikeneddemographicgrowthto“along,thinpowderfusethatburnssteadilyandhaltinglyuntilitfinallyreachesthechargeandexplodes.” Tounderstandthecurrentsituation,whichischaracterizedbyrapidincreasesinpopulation,itisnecessarytounderstandthehistoryofpopulationtrends.Rapidgrowthisacomparativelyrecentphenomenon.Lookingbackatthe8,000yearsofdemographichistory,wefindthatpopulationshavebeenvirtuallystableorgrowingveryslightlyformostofhumanhistory.Formostofourancestors,lifewashard,oftennasty,andveryshort.Therewashighfertilityinmostplaces,butthiswasusuallybalancedbyhighmortality.Formostofhumanhistory,itwasseldomthecasethatoneintenpersonswouldlivepastforty,whileinfancyandchildhoodwereespeciallyriskyperiods.Often,societieswereincleardangerofextinctionbecausedeathratescouldexceedtheirbirthrates.Thus,thepopulationproblemthroughoutmostofhistorywashowtopreventextinctionofthehumanrace. Thispatternisimportanttonotice.Notonlydoesitputthecurrentproblemsofdemographicgrowthintoahistoricalperspective,butitsuggeststhatthecauseofrapidincreaseinpopulationinrecentyearsisnotasuddenenthusiasmformorechildren,butanimprovementintheconditionsthattraditionallyhavecausedhighmortality. Demographichistorycanbedividedintotwomajorperiods:atimeoflong,slowgrowthwhichextendedfromabout8,000BC.tillapproximatelyAD.1650.Inthefirstperiodofsome9600years,thepopulationincreasedfromsome8millionto500millionin1650.Between1650andthepresent,thepopulationhasincreasedfrom500milliontomorethan4billion.Anditisestimatedthatbytheyear2000therewillbe6.2billionpeoplethroughouttheworld.Onewaytoappreciatethisdramaticdifferenceinsuchabstractnumbersistoreducethetimeframetosomethingthatismoremanageable.Between8000BCand1650,anaverageofonly50,000personswasbeingaddedannuallytotheworld’spopulationeachyear.Atpresent,thisnumberisaddedeverysixhours.Theincreaseisabout80,000,000personsannually. 1.Whichofthefollowingdemographicgrowthpatternismostsuitableforthelongthinpowderfuseanalogy? A.Avirtuallystableorslightlydecreasingperiodandthenasuddenexplosionofpopulation. B.Aslowgrowthforalongtimeandthenaperiodofrapid,dramaticincrease. C.Toomanypeopleonearthandafewrapidincreaseinthenumberaddedeachyear. D.Alongperiodwhendeathratesexceedsbirthratesandthenashortperiodwithhigherfertilityandlowermortality. 2.Duringthefirstperiodofdemographichistory,societieswereoftenindangerofextinctionbecause___. A.onlyoneintenpersonscouldlivepast40. B.therewashighermortalitythanfertilityinmostplaces. C.itwastoodangeroustohavebabiesduetothepoorconditions. D.ourancestorshadlittleenthusiasmformorechildren. 3.Whichstatementistrueaboutpopulationincrease? A.Theremightbeanincreaseof2.2billionpersonsfromnowtotheyear2000. B.About50,000babiesareborneverysixhoursatpresent. C.Between8000BCandthepresent,thepopulationincreaseisabout80,000,000personseachyear. D.Thepopulationincreasedfasterbetween8000BCand1650thanbetween1650andthepresent. 4.Theauthorofthepassageintendsto___. A.warnpeopleagainstthepopulationexplosioninthenearfuture. B.comparethedemographicgrowthpatterninthepastwiththatafter1650. C.findoutthecauseforrapidincreaseinpopulationinrecentyears. D.presentusaclearandcompletepictureofthedemographicgrowth. 5.Theword“demographic”inthefirstparagraphmeans___. A.statisticsofhuman. B.surroundingsstudy. C.accumulationofhuman. D.developmentofhuman.
翻译训练：大学生创业近年来大学生创业(entrepreneurship)问题越来越受到社会的关注,因为受过多年教育的大学生属于高级知识分子,他们背负着社会的种种期望。在社会经济繁荣发展的同时,大学生创业也成为新气象。现代大学生有创新精神,有对传统观念和传统行业挑战的信心和欲望,而这种创新精神也成为大学生创业的动力源泉,成为成功创业的信心基础。大学生怀揣创业梦想,努力打拼,实现自己的理想,证明自己的价值。
汉译英：流逝，表现了南国人对时间最早的感觉。“子在川上曰，逝者如斯夫。”他们发现无论是潺潺小溪，还是浩荡大河，都一去不复返，流逝之际青年变成了老翁而绿草转眼就枯黄，很自然有错阴的紧迫感。流逝也许是缓慢的，但无论如何缓慢，对流逝的恐惧使人们必须用“流逝”这个词来时时警戒后人，必须急匆匆地行动，给这个词灌注一种紧张感。
如果你竟聘上岗后，负责一个科技项目，在项目研发的关键时刻，你的两个技术骨干突然辞职，你怎么办?
联合承包人怎么样承担各自的责任?
Writing: Somepeopleclaimthat,intheageoftelevision,readingbooksisnotasimportantasitoncewasandthatpeoplecanlearnasmuchbywatchingtelevisionastheycanbyreadingbooks.Doyouagreeordisagreewiththisstatement?Writeanessayofabout400words. Inthefirstpartofyouressayyoushouldstateclearlyyourmainargument,andinthesecondpartyoushouldsupportyourargumentwithappropriatedetails.Inthelastpartyoushouldbringwhatyouhavewrittentoanaturalconclusionormakeasummary. Youshouldsupplyanappropriatetitleforyouressay. Markswillbeawardedforcontent,organization,grammarandappropriateness.Failuretofollowtheaboveinstructionsmayresultinalossofmarks.