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科技英语翻译
1.1翻译的标准第1节翻译练习1Thepowerplantistheheartofaship.Thepowerunitfordrivingthemachinesisa50-hpinductionmotor.动力装置是船舶的心脏驱动这些机器的动力装置是一台50马力的感应电动机第1节翻译练习2Semiconductordevicescalledtransistorsarereplacingtubesinmanyapplications.Crampedconditionsmeansthatpassengers’legscannotmovearoundfreely.Allbodiesareknowntopossessweightandoccupyspace.半导体装置也称为晶体管,在许多场合替代电子管我们知道,所有的物体都有重量并占据空间空间狭窄,旅客的两腿就不能自由活动第1节翻译练习3Theremovalofmineralsfromwateriscalledsoftening.Atypicalfoliageleafofaplantbelongingtothedicotyledonsiscomposedoftwoprincipalparts:bladeandpetiole.去除水中的矿物质叫做软化双子叶植物典型的营养叶由两个主要部分组成叶片和叶柄
1.2对译者的要求第4节翻译练习1Einstein’srelativitytheoryistheonlyonewhichcanexplainsuchphenomena.Allfourouterplanetsprobablyhavecoresofmetalssilicatesandwater.爱因斯坦的相对论是能解释这种现象的唯一理论(直译)这四颗外层行星的内核可能都由金属、硅酸盐和水构成(意译)Thedesignermusthaveaccesstostocklistsofthematerialsheemploys.Partadjustmentandrepairmustbeperformedonregularbasisifanacceptableprintedproductistobetheendproduct.设计师必须备有所使用材料的储备表(意译)要使印刷品的质量达到要求,部件调试及修理就必须定期进行(意译)第4节翻译练习2Themostimportantofthefactorsaffectingplantgrowthisthatitrequiresthesupplyofwater.Thedoctoranalyzedthebloodsampleforanemia.Theapparentchangeinsizeofthesuniscausedbydustintheairnearthehorizon.植物生长的各因素中最重要的是水的供应(合译)太阳的大小看起来有变化,这是由于靠近地平线的空气中有尘粒而引起的(分译)医生对血样作了分析,看是不是贫血症(分译)Thesefragmentsofrockandironrangefromthousandkilometersindiametertolessthanone.Manufacturingprocessesmaybeclassifiedasunitproductionwithsmallquantitiesbeingmadeandmassproductionwithlargenumbersofidenticalpartsbeingproduced.这些石块和铁块的碎片大小不等,大的直径有1000公里,小的不到1公里(分译)制造过程可以分为单件生产和大量生产前者指的是生产少量的零件,后者则是指生产大量相同的零件(分译)第4节翻译练习3Cartographyisthescienceofmakingmaps.Manyelementsinnaturearefoundtobemixturesofdifferentisotopes.制图学是研究绘制地图的科学(增译)人们发现,自然界里许多元素,都是各种不同的同位素的混合物(增译)Thetwounitsusedmostfrequentlyinelectricityareampereandvolt:thisistheunitofvoltageandthatofcurrent.Thatlikechargesrepelbutoppositechargesattractisoneofthefundamentallawsofelectricity.电学上最常用的两个单位是安培和伏特后者是电压的单位,前者是电流的单位(增译)同性电荷相斥,异性电荷相吸是电学的一个基本规律(省译)第4节翻译练习4Almostanyinsulatedbodyprocessestosomeextenttheabilitytoretainforatimeanelectriccharge.Theangularcontactbearingprovidesagreaterthrustcapacity.Thepropertiesoftheweldcanbealteredbyvaryingthegrainorientation.几乎任何一种绝缘体都多少具有保留电荷一段时间的能力向心推力轴承有较大的轴向承载能力通过改变晶粒的方向可以改变焊缝的性能
2.1词义的选择第1节翻译练习1Thespindlerotatessimultaneouslyroundtwoaxesatrightanglestoeachother.Theearthisn’tcompletelyround;itisslightlyflattenedatthepoles.Ineachroundofoperationtheparticlepicksupenergyfromtheoscillatingelectricfield.锭子同时绕两个互相垂直的轴旋转(介词)粒子每运转一周都从振荡电场获取新的能量(名词)地球并非完全是圆的,它的两极略扁平(形容词)Anelectronisanextremelysmallcorpusclewithnegativechargewhichroundsaboutthenucleusofanatom.Herwaistmeasuresfortyinchesround.电子是绕原子核转动且带有负电荷的极其微小的粒子(动词)她腰围40英寸(副词)第1节翻译练习2Rateofpenetrationwasfoundtobeproportionaltothenetpressureappliedbythetool.Scientistsareconstantlystrivingtofindfastandconvenientwayofobtainingquantitativedata.Tofindtheareaofasquareoroblongyoumerelymultiplyitslengthbyitswidth.Certainisotopesarenotfoundinnature.人们发现钻孔速度与工具所受的净压力成正比求一正方形或长方形的面积,你只需将其长度乘以宽度科学家们总是力求找到快速而简便的方法获得定量数据有些同位素在自然界中并不存在Newfibersfindexpandingapplicationsinengineeringandindustry.KangaroosarefoundinAustralia.Thisplantisfoundintheseanearthemouthofrivers.Microcomputershavefoundtheirapplicationintheproductionofgeniussensors.Plasticsfindwideapplicationinourdailylife.大袋鼠产于澳大利亚这种植物生长在近河口的海中新发明的纤维在工程和工业领域得到越来越广泛的应用微型计算机已经应用于智能传感器的生产中塑料在我们的日常生活中得到广泛应用第2节翻译练习1Thecauseofrollingresistanceisthedeformationofmatingsurfacesoftherollingelementandtheracewayonwhichitrolls.TraditionallyNCprogramminghasbeenperformedofflinewiththemachinecommandsbeingcontainedonapunchedtape.Theoccurrenceoflargematsoffloatingalgaemayresultinthedeathofmanyfishfromlackofoxygen.滚动阻力的起因在于滚动体的配合面和它滚动的滚道的变形(技术性引申)通常,数控机床的编程是脱机完成的,指令载于穿孔带上(技术性引申)大片大片漂浮的藻类的出现导致很多鱼因缺氧而死亡(修辞引申)Thesplittingoftheuraniumorplutoniumnucleusisaccompaniedbythereleaseofveryconsiderableamountofenergy.Themajorcontributorsincomponenttechnologyhavebeeninthesemiconductor.Thedistancebetweenthetwoplatesissmallcomparedwiththeirlineardimensions.Justasdifferentsolidsandliquidsvaryindensitysodogasesandvapors.元件技术中起主要作用的是半导体元件(具体化引申)两板之间的距离相对于其宽度和长度而言比较小(具体化引申)随着铀核和钚核的裂变,会有极其巨大的能量释放处理(修辞性引申)正像不同的固体和液体的密度不同一样,不同的气体和蒸汽的密度也不同(具体化引申)TheCuriesbelievedthattherewassomethinginnaturethatgaveoutradiation.Obviouslythereismuchroomfortheimprovementinthestructure.Atpresentcoalisthemostcommonfoodofasteamplant.Thefactshavebeensetdowninblackandwhite.显然,其结构还有较大的改进余地(抽象化引申)目前,煤是火电厂最常用的能源(抽象化引申)居里夫妇坚信,自然界中有一种物质能放出辐射能(具体化引申)这些事实已经清清楚楚地记录下来了(抽象化引申)
2.3词类的转换第3节翻译练习1Eachtimeasamplewasdrawnforcolordetermination.WhatiscertainisthattheoilspillhasdeliveredadevastatingblowtotheecologyofthePersianGulf.Weshouldgetfamiliarwithdifferentsystemsofunits.每次取一个标本测定颜色可以肯定,这场石油泄漏事件对波斯湾的生态是个惨重的打击我们应该熟悉各种(计量)单位制Thesedecision-makingprocessesareapplicabletotheentirefieldofengineeringdesign---notjusttomechanicalengineeringdesign.Hydrogeninsteadofairisfrequentlyusedforcoolinglargeturbogenerators.WhenthewarwasoveritwasdiscoveredthattheGermanswerenowherenearsuccessindevelopingnuclearweapons.常以氢气代替空气来冷却大型汽轮发电机第二次世界大战结束后,人们发现德国人在研制核武器方面离成功还很远这些判定过程可以应用于工程设计的整个领域,而不仅仅限于机械工程设计Variousprecautionshavebeentakenagainstleakage.Onceinsidetheovenpanelsaresubjectedtoatemperatureof365°F.Valueisdefinedasanumericalratiotheratioofthefunctionorperformancetothecost.Thisnewmodelshouldappealtopotentialbuyers.一旦进入烘干炉,板材就处于365华氏度的温度条件下价值的定义是功能或性能与成本的数值比已采取了各种措施防止渗漏这种新式样对潜在的买主肯定有吸引力Galileo’sexperimentsarenotdifficultnoristhereanyevidencethatheperformedthemwithexceptionalskill.Sometimesascientistobservesanobjectanditsfeaturesforexampleastarorabird;sometimesheobservesaneventwhichissomethingthathappensataparticulartime.Earthquakesaregenerallymoredestructiveoflifethanvolcaniceruptions.有时科学家观察一物体及其特征,例如一颗星或一只鸟;有时科学家观察某一事件,即在一特定时间所发生的事地震对于生命的破坏通常大于火山爆发伽利略的实验并不难,也没有证据表明他是以非凡的技能来做实验的Heatshouldbeappliedslowlytoavoidlocalizedoverheating.Howrapidlyafuelburnsdependsonhowthoroughlyitismixedwithoxygenorair.Thisiswhyacoilisoftenreferredtoasaninductor.一种燃料燃烧的速度有多快,取决于它与氧气或空气混合的均匀程度这就是线圈常被叫做电感器的原因应当慢慢加热,以避免发生局部过热现象第3节翻译练习2Practicallyalloftheusefulpropertiesofmaterialsarestronglydependentontheirinternalstructure.Themetalcastswell.Awireforconductingelectriccurrentiscoveredwithplastic;theplasticisinsulationroundthewire.几乎材料的一切有用特性都与其内部的结构有密切的关系这种金属有良好的铸造性能传导电流的导线包有塑料,该塑料便是导线周围的绝缘材料Therearemanywaysofdeterminingthedistributionofthemagnetismaboutamagnet.Goodlubricationkeepsthebearingsfrombeingdamaged.Safetyinapowerplantisofgreatimportance.Mostmoderntransmittersemploysolidstatecircuits.安全在电厂是非常重要的现代发报机大多采用固体电路有许多方法来确定磁场周围的磁力分布状况润滑良好可保护轴承不受损伤E-Chemmercenowofferstwomainlevelsofonlinebusinessintelligenceonchemicalplasticandenergye-commerce.Theseimagestendtoexaggeratetherobot’ssimilaritytohumananatomyandbehavior.Aluminumremainedanexpensiveraritytillthediscoveryoftheelectrolyticprocessforreducingaluminumin
1886.这些概念常常夸大了机器人与人类在形体和行为方面的相似之处《电子化工商务》目前主要提供两个层次的有关化学、塑料和能源电子商务的在线商务信息服务直到1886年人们发现电解法还原铝之前,铝一直是一种昂贵的珍品Sincesomematerialsarenotdamagedeasilyasothersthepossibilityexistsofdevelopingradiation-resistantparts.由于有些材料不像另一些那样容易被损坏,所以有可能研制出防辐射的零件
2.4词的增译第4节翻译练习2第4节翻译练习1Thisactionexternallyappearslikethedischargeofacapacitor.Onceoutoftheearth’sgravityanastronautisaffectedbystillanotherproblem---weightlessness.Byminimizingthemicroscopicimperfectionsscientistsaremakingfarstrongerceramics.这一作用从外表上看来像电容器的放电现象一旦离开了地球的引力范围,宇航员又遇到了另一个问题——失重科学家们正通过最大限度地减小微观缺陷来制造强度高得多的陶瓷Atomiccellsaresmallandverylightascomparedtoordinarydryones.Transistorscanmakepreviouslylargeequipmentmuchsmaller.Astronomershaveevidenceofafewotherstarstoowhichmighthaveblackholesascompanions.天文学家有证据表明,还有其他一些恒星也可能有黑洞作为伴星和普通电池相比,原子电池体积小、重量轻晶体管能使原先体积大的设备变得小得多Thekeytothenewmaterialsisresearchers’increasingabilitytomanipulatesubstancesatthemolecularlevel.Thelargestandmostexpensiveproductscannotbecauseoftheirsizebetestableinthefactory.Coldrollingenablestheoperatorstoproducerollsofaccuracyanduniformityandwithabettersurfacefinish.最大最贵的产品,因为体积大,在该工厂里是不能检验的开发新材料的关键在于研究人员不断提高在分子一级上处理物质的能力冷轧可使操作工生产出精确度高、均匀度好的轧制件,并具有更好的表面光洁度Allthesefactorsplayakeyroleinformulationofthemodel.PCsarenotthemoststableandwithvideoeditingyouhavetobeextracareful.Thismethodmakesiteasytoidentifythevariouscomponents.在拟订模型时,所有这些因素都将起到关键性的作用这个方法使人们很容易识别各种不同的构成成分个人电脑一般并不太稳定,所以,进行视频编辑时需要加倍小心第4节翻译练习2Itwasestimatedthatthepowerofanaveragehorseisequalto500feet-poundspersecond.Panelpatchisonegaugeheavierthanthicknessoforiginalskin.Studieshaveshownthatinformationcanbecommunicatedtopeoplemanytimesfasterinagraphicformthaninwrittenform.据估计,一匹普通马的功率等于500英尺-磅力/秒补块比原板的厚度大一号众多研究表明,以图形表示的信息被人们接受的速度比以文字表示的快许多倍Thechemistismakingananalysisofthepoison.Itappearsthattheconstructionofthedamhashadaconsiderableeffectontheecologyoftheregion.Thereceiverwilloperatereliablynomatterwhathappens.无论发生什么情况,这台接收机都将可靠地工作药剂师正对毒性进行分析看来,建造水坝对这一地区的生态已经有相当大的影响Radiantelectricalandchemicalenergiescanallbeturnedintoheat.Thefrequencywavelengthandspeedofsoundarecloselyrelated.Noisefigureisminimizedbyparametricamplifier.频率、波长和声速三者是密切相关的辐射能、电能和化学能这三种能均可转变为热能采用参量放大器即可将噪音系数减小至最低限度Intheabsenceofsufficientknowledgeconfusionexistsinclassifyingaspecimenasabutterflyoramoth.Leadcanbehammeredintoverythinsheetswithoutbeingbroken.Thereareanumberofdevicesthatgiveanelectriccurrentwhenlightfallsonthemwithoutanychemicalchangestakingplace.如果没有足够的知识,就分不清标本是属蝶类还是蛾类有许多器件在受光照射时能产生电流,但不发生任何化学变化铅能被锤成很薄的薄片而不破裂
2.5词的省译第5节翻译练习1Thefactthattheconcreteisslowinsettingisnosignthatitisofpoorquality.Suchanengineiscalledaninternalcombustionengine.Thesymptomsofhepatitisaresimilarnomatterwhichvirusisinvolved.混凝土凝固得慢并不表示其质量差这种发动机成为内燃机肝炎不管是由何种病毒引起的,其症状均大同小异Thiscriticaldeficiencywasitselfduetothreefactorswhichinteractedwitheachotherovertheentireperiod.Thepropertieschangeingoingfromcarbontographite.Thedesignchoiceshingeuponconsiderationsofgainnoisefigureandsoforth.设计选择的关键在于考虑增益、噪音系数等等这个关键性的逆差来源于三个始终互相影响的因素碳转变成石墨时,其性质也发生了变化Temperaturesmayreach700°Candsurfaceoxidationbecomescritical.Iftheatomicnucleusofaheavyelementissplitalargeamountofenergyisreleased.Thediscoveryofenzymesisveryimportantbecauseitgaveimpetustoaseriesofexperiments.分裂一重元素的原子核,会释放出很大的能量温度高达700摄氏度,表面氧化便成为关键问题酶的发现很重要,因为它推动了一系列试验的进行Apartfromthefactthatitmaybecomehotnoapparentchangeoccursinametalwhenitiscarryingacurrent.Thisequipmentformsanintegralpartofmanyadvancedsystems.Therewasariseintemperatureandasaresultthecomponentfailed.金属有电流通过时,除了金属可能变热外没有什么显著变化温度升高了,结果元件出了故障这个设备是许多先进系统不可缺少的一部分Ifthereislittlecoolingwateravailableadieselenginemakesanexcellentprimemoverforgenerationbelow10000kVA.Therewasablockinthepipeandthewatercouldnotflowaway.如果能利用的冷却水不多,则柴油发动机可以成为极好的发电10000千伏安以下的原动机水管被东西堵住,水流不出去
2.6重复法第6节翻译练习1Thepropertiesofgasarequitedifferentfromthoseofliquid.Theelectricresistanceofcopperisnotsolargeasthatofiron.Thethreegaslawsaretrueofallgasesaswellasofair.气体的性质与液体的性质大不相同(重复名词)气体三定律不但适用于空气,也适用于所有气体(重复动词)铜的电阻不像铁的电阻那样大(重复名词)Matterchangesnotonlyinstatebutalsoinvolume.Continuousdatacanbeexpressedineitherfractionsorwholenumbers.物质不仅形态改变而且体积也改变(重复动词)连续资料可以用分数表示,也可以用整数表示(重复动词)
3.1名词的译法第1节翻译练习1Inanunusualapplicationthisorganizationusesafingerprintscannertomonitorthecomingsandgoingsofitsresidents.Acapacitorisusedtoeliminatesparkingwhenacircuitcontaininginductanceissuddenlyopened.一个不同寻常的用途是这个机构使用指纹扫描器监视居住人员的进出当含有电感的电路突然断开时,可用电容器消除火花第1节翻译练习2Thecomparisonrevealsthattheerrorisduetoaliasing.Thescansconfirmedthatthesubjects’brainsdealtwithwordsinwaysthatcontradictonehoaryoldidea.Thelatestresearchwithradioactiveisotopeshasshownthatthisassumptionisquitewrong.比较结果表明,误差是由于名称不同而造成的扫描结果证实,受试者的大脑处理词的方式同一种古老的旧观念不一致对放射性同位素的最新研究结果表明,这种设想是完全错误的Metalsdifferintheeasewithwhichtheygiveupelectronsandenterintochemicalcombination.Internal-shoedrumbrakesprovidebetterprotectionfromwateranddust.Peopleonearthareprotectedfromthedangerousultravioletradiationofthesunbyalayerorozonethatspanstheplanetandabsorbstheradiation.各种金属放出电子和参与化学反应的难易程度不一内蹄式鼓形制动器的防水、防尘性能比较好地球上的人们受到包围着地球并能吸收辐射的一层臭氧层的保护,从而免受危险的太阳紫外线辐射的伤害Accordingtothemoleculartheorythetemperatureofanobjectdependsontheaveragespeedofitsmolecules.Effectivenessoftemperaturecontroldependsupontheamountoflubricantsuppliedtheambienttemperatureandtheexternalcooling.根据分子理论的原理,物体的温度取决于其分子的平均速度温度控制的效果取决于润滑剂的用量、环境温度以及外部的冷却设施第1节翻译练习3Particularattentionshouldbegiventohosestoensurethatchafingdoesnotoccur.Theprimaryconcernofelectricalengineeringisthedoingofworkbythedeliveryofenergy.Genepiracyisnotnew.Allplantsandanimalsneedcarbonforgrowth.要特别注意软管,保证没有擦伤窃取基因不是新鲜事电工学主要关注的是通过输送能量做功的情况所有动植物均需要碳才能生长第1节翻译练习4Theexperimentwasasuccess.Semiconductordevicescanperformavarietyofcontrolfunctioninelectronicequipment.这个试验是成功的半导体在电子设备中能起各种各样的控制作用
3.2冠词的译法第2节翻译练习1Apolymerisasubstanceofhighmolecularweight.Beingagoodinsulatorrubberisoftenusedincables.Thepatientwasadministeredthemixturetwiceaweek.Thesemachinesmaybeoiledonceortwiceamonth.聚合物是一种高分子的物质这种混合剂病人每周服用两次橡胶是一种良好的绝缘体,所以经常使用在电缆上这些机器每个月可以加一次或两次油第2节翻译练习2Abearingcanbedefinedasamemberspecificallydesignedtosupportmovingmachinecomponents.Useatransformerandpoweratlowvoltagecanbechangedintopowerathighvoltage.Anobjectatresthasnokineticenergyitsvelocitybeingzero.轴承可以定义为一种专门用于支撑运动着的机器零件的构件静止的物体没有动能,因为它的速度为零使用变压器可将低压电转变为高压电第2节翻译练习3作为固定词组时的省译onalargescaleamajorityofawealthofasaresult结果,因此大规模地大多数的大量的第2节翻译练习4Themachineisintendedforgrindingthetopandbottomsurfacesoftungstencarbidetips.Themechanismhasbeentermedcumulativefeedbackinhibition.该机床是供磨削硬质合金刀片上下表面用的这种机制就叫做累加反馈抑制第2节翻译练习5Thebasicjobofthecomputeristheprocessingofinformation.Themaineffectistoraisethefundamentalsloshmodefrequency.计算机的基本任务是处理信息主要作用在于提高基本的晃动频率第3章总复习题Otherfactorsaffecttheconfigurationofthetotalsystem.Innormalflightthehatchdoorsfairintothefuselage.Energycanneitherbecreatednordestroyedbyanymeansknowntoman.另一些因素则将影响整个系统的结构飞行正常时,舱门与机身平整贴合用人们已知的方法,既不能创造能量也不能消灭能量Itiscustomarytorefertodesignlevelsashighorlowoncomponentcomplexity.Themaineconomyofthesystemstemsfromtheabilitytomovecarsinacontinuoustrainwithoutuncoupling.Heisastrangertotheoperationoftheelectroniccomputer.他对电子计算机的操作是陌生的习惯上根据部件的复杂程度把设计级称为高设计级和低设计级此系统的主要经济之处在于它能移动列车的车厢而不必将它们脱钩分开Akeyelementinsystemcapacityplanningisthefinancialcostofperformance.Theassemblercanexpandthekeywordsintheassemblycodeintotheirfullinstructionset.Theflamedoesnottouchtheflaskdirectly.这种汇编程序能把汇编码中的关键字扩展成完整的指令集系统能力计划中关键因素是性能的金融成本火焰没有直接接触烧瓶Thestudyofthestrengthofsolidsinvolvesthestudyofthedefectsinthecrystallinestructure.Theproblemwassolvedbytheprovisionofacompensatingjet.Therustingofironistheslowchemicalcombinationoftheelementsironandoxygeninmoistatmosphere.研究固体的强度,就必须研究晶体结构中的缺陷铁生锈是铁元素和氧元素在湿空气中缓慢化合的现象通过安装一个补偿喷嘴,解决了这个问题Thedecayoforganicmatterisaslowoxidationbyoxygenintheair.InordertoimproveacertainkindofbatteryEdisonspentalmosttenyearsandmadenearly50000experiments.有机物的腐烂是空气中的氧引起的一种缓慢氧化过程为了改善一种电池的性能,爱迪生花了差不多十年时间,做了近50000次试验
4.1代词的一般译法第1节翻译练习1Inthiscellthelightincidentonthesensitivesurfaceofthecellcausesthephoto-electricemissionofelectronsfromthesurfaceandtheseelectronsareattractedtotheotherelectrode.Theowlcanhearamousechewingandflydownoniteventhoughitishiddenfromsightunderapileofleaves.在这种电池中,照在电池光敏表面光电效应而发射电子,而这些电子被吸引到另一电极即使老鼠躲藏在一堆叶子下看不见的地方,猫头鹰也能听见老鼠咀嚼的声音而飞下来袭击它Thismightbecomparedwiththemumbleofwavelengthsofsoundthatgotomakeupordinarynoise.这可以与杂乱的声波相比,一般的噪音就是由这种杂乱的声波组成的第1节翻译练习2Drawingelectronsawayfromtheatomcausesittohaveanetpositiveelectriccharge.Eachcrystalshouldhaveashapeasmuchlikethatoftheothercrystalsaspossible.将电子与原子分离会使原子带上纯净正电荷每一结晶的形状应与其他结晶的形状尽可能相似第1节翻译练习3Everyelementretainsitsidentitynomatterhowitisfinelydivided.Astronomerscanestimatethesizeandbrightnessofastarbyitscolor.每种元素不论分得怎样细小,它仍保持其特征天文学家根据恒星的颜色可以估计它的大小和亮度第1节翻译练习4Manyprocesseshavealreadybeenproposedandonepossiblefutureprocessisasmeltingreduction.Itispossibletoworkbackwardfromtheknownstrengthanddeterminewhatfactorofsafetywasused.Eachisasolidspherewithametalliccoresurroundedbysilicateshells.我们能够由已知的强度反过来求出所用的安全系数它们每一颗都是由硅酸盐外壳包围着金属内核的固态球体人们已经提出了很多方法,未来可能的选择之一就是熔融还原法第1节翻译练习5Inthischapterourtaskistofindoutwhattheairismadeof.Todaywehaveafairlyclearideaofwhatgoesoninsideofatom.Practicallyalloftheheatenergyreceivedbytheearthcomesfromthesun.现在我们对原子内部的情况已相当清楚了地球所得到的热能几乎都来自于太阳在这一章中,我们的任务是弄清空气的构成成分
4.2人称代词的译法第2节翻译练习1Youcandecidewhatresolutionandcompressionlevelisbestforyouroutput.We’lldoeverythingpossibletoimprovethesupplyofelectricity.Youcanfindthedensityofabodyprovidingyouknowitsmassandvolume.Wemustbeverycarefultoavoidtryingtoexpressenergyintermsofpowerunits.我们将尽一切努力来改善电力供应只要知道物体的质量和体积,就可求出物体的密度你可以决定哪种溶解和压缩程度对成品最好必须注意避免用功率单位表示能量第2节翻译练习2Itmayrequirethetakingofalargesampleasinmacroanalysis.Ifanatomcontainsthreeprotonsitmusthavethreeelectronstobeelectricallyneutral.如果一个原子有三个质子,这个原子必然有三个电子来使其呈电中性它可能要求像宏观分析中那样采用大的样本
4.3形容词性物主代词的译法第3节翻译练习1Thedensityofanythingisitsmassperunitvolume.Eachsubstanceshowsanindividualstructureofitsown.Oneofthedrawbacksoftheearlylaserswastheirinabilitytooperatecontinuously.每一种物质都显示出它自己的独特结构任何物体的密度是它的每单位体积的质量早期激光器的缺点之一是它们不能连续地工作第3节翻译练习2Intheirworkshopthereisnoonewhounderstandshowacomputerusesitstubes.Transistorsaremoreadvantageoustovacuumtubesfortheirbeingsmallandlight.Thetransformercannotbecalledamachinebecauseofitshavingnomovingparts.晶体管优于真空管,因为它尺寸小、重量轻在他们车间,无人能理解计算机是怎样使用其电子管的变压器不能称为机器,因为它没有转动的部件第3节翻译练习3Accordingtotheirabilitytoconductelectriccurrentallmaterialsmaybeclassifiedintothreemajorcategories:conductorssemiconductorsandinsulators.Youshouldn’thavetouchedthewirewithyourwethands.你不该用湿手触摸导线根据导电的性能不同,所有的材料可分为三大类导体、半导体和绝缘体第3节翻译练习4Heatingsemiconductorsmeansincreasingtheirconductivity.Trianglescanbeclassifiedaccordingtotheiranglesortherelativelengthsoftheirsides.Accordingtotheircompositiontheserawmaterialsmaybeseparatedintothreegroups.Thebrainhasitsmanagingsystem.三角形可按照其角度或其相对边长来分类根据这些原材料的构成成分,它们可以分为三种类型加热半导体就会增加其导电率大脑有自己的管理系统
4.4指示代词的译法第4节翻译练习1Allatomsexceptthoseofhydrogencontainoneormoreneutronsinthenucleus.Thespeedoftheobjectapproachesthatoflight.Thegeometryofthetestspecimensdiffersfromthegeometryofthoseusedintensiontests.所用试件的形状和尺寸与拉伸试验的试件不同除了氢原子外,所有的原子都有一个或几个中子该物体的速度接近光速第4节翻译练习2Itdiffractsthediffractedbeamandthismeansthatitgeneratesaninversetransform.Heatisaformofenergyandthatisknowntoallofus.Theyusedthetransformersofpoorqualityandthiscausedthewholepowersupplysystembreakdown.他们用了一批劣质的变压器,使得整个供电系统陷于瘫痪热是能的一种形式,这是大家都知道的它对衍射光束发生衍射,这意味着它产生了一个逆变换第4节翻译练习3Thisisasimplecriterionthatguaranteestheexistenceofsucharepresentation.Thepercentageofsuchcasesamongsurgicalpatientscanbedeterminedinthefollowingmanner.在接受手术的病人中,这样的病例所占的百分比可用下述方法确定这是确保这种等值表达式存在的一个简单标准第4节翻译练习4Asarulesolidsandliquidsexpandwhenheatedwaterdoesthesameexceptnearitsfreezingpoint.Thesameistruewhenanalternatingvoltageisappliedtoaresistance.按照固体和液体遇热膨胀的原理,水除了接近其冰点的情况之外也是如此当交流电压加在电阻上时,情况也是一样的第4节翻译练习5Allmotioninthisuniverseistheformofsuccessivelyrisingandfalling.Seriesdohavetheadvantageofincreasingresistancetoreducecurrentwhenthisisdesirable.串联电路的确有这样的优点在需要时可以增加电阻来减少电流宇宙内的一切运动,均处在连续上升和下降的状态中
4.5不定代词的译法第5节翻译练习1Alltheseelementscanbeusedinsemiconductormanufacture.Alltransformersandelectricmachineryusemagneticmaterial.Alltheshaftswerecutfromheavyplanksofwood.所有的变压器和电机都使用磁性材料在半导体生产中,所有这些元件都能用上箭杆都是用厚木板削制而成的AlmostallwhodieofAIDSactuallydieofstarvation.Allthecurrentsatnodewerenottoadduptozero.Notalltheenergyfromanantennaisradiatedinthemainbeam.NotallpeoplewhotestpositivefortheAIDSantibodygetthediseaseAIDS.几乎所有丧命爱滋病的患者都是死于饥饿并非所有节点上的电流总和为零天线能量并不都是由主波束辐射的并不是所有的爱滋病抗体试验为阳性的人都患有爱滋病第5节翻译练习2Theequipmentwillcompensateforanydimensionalvariationscausedbywheelwear.Anyportionoftheflightcontrolsystemmaybereadilyremovedinanysequencebytheremovalofattachingboltsandnuts.Whichifanyofthethreestatementsbelowarefalse拆卸了原装的螺钉及螺母,便可很快地按任意顺序拆除飞机控制系统的任何部分该装置对砂轮磨损引起的任何尺寸误差给予补偿下面三种说法中如果有错,那么是其中的哪一种?WhatifanyeffectdoyoufeeltheimportsofCanadiangaswillhaveontheAmericanproducerTherearefewifanyofthemknowtheconstructionofthetransformer.你觉得进口加拿大的天然气对美国的生产者可能产生什么影响吗?他们当中几乎没人懂得变压器的结构第5节翻译练习3Bothalternativesarepresentedonthescreen.Velocityisavectorquantityinvolvingbothmagnitudeanddirection.速度是一种矢量,既有大小,又有方向两种选择都在屏幕上显示出来了第5节翻译练习4Eachofthebitshasadifferentoptimumcuttingspeed.Therearemanytypesofefficientwaterpumpseachdesignedtomeetaspecificneed.Everyelementnomatterhowitisfinelydividedretainsitsidentity.效率高的水泵有多种类型,每一种都用来满足某个特定的需要每个钻头都有一个不同的最佳切割速度每种元素不论分得怎样细小,仍保持该元素的特征Onehalfofthemediumwasrenewedeverythreedays.Ithasanerrorrateofoneortwowordsineveryhundred.Noteveryminutedifferenceisnoted.每三天更换一半溶剂误差率是每百字有一两个错误并非每一个细微的差别都被注意到了第5节翻译练习5Withoutelectricityneithermachinecouldbestared.Ibelieveeithermethodwilldo.我看两种方法中的任何一种都行没有电,这两台机器都开动不了第5节翻译练习6Sometimesonefindsinfossilstonestheimprintofaleaf.Thelastsoundtoreachthereceivingshipistheonethathitsthebasement.Neutrinosfromasubsidiarydecayprocessaretheonestobedetected.传到接收船上的最后的声音就是碰到底层的声音有时人们能在化石里发现一片树叶的痕迹有待探测的中微子来自次要的衰变过程Drivingmachinesarealwaystheoppositeofdrivenones.Oneofthemostsuccessfulmethodsofachievingthisdependsontheuseoffluidization.Oneoftheusesofthetriodeisthatitcanamplify.主动机和从动机总是相反的达到这一目的的最成功的方法之一就是采用流化技术三极管的用途之一是放大Oneswhomakethedecisionsonwhatwentintothesystemareprogrammers.OneswhoclaimECTisbotheffectiveandsafeinfactcannotproveit.Therearetwo300MWthermalpowerunitsinthispowerplant.OneismadeinChina;theotherisimportedfromGermany.决定要把什么写进系统的人是专业编程人员那些宣称电痉挛疗法既有效又安全的人,实际上并无法证明他们的观点这家电厂有两台30千瓦火力发电机组,一台是国产的,另一台是从德国进口的Therearetwokindsofelectriccurrents.Oneisthedirectcurrent;theotheristhealternatingcurrent.电流有两种,一种是直流电流,另一种是交流电流第5节翻译练习7Thischemicalispoisonous.Othersarepoisonoustoo.Somepartsrequireahardtoughmetalandothersmaybemadeofsoftermetals.Thecoolantservesnootherpurposethantoremoveexcessheat.Someatomicnucleiundergospontaneousdisintegrationwhileothersdonot.冷却剂除了排除多余的热以外没有任何其他用处这些化学制品有毒,别的化学制品也有毒有些零件需要由硬的韧性金属制成,而有些则可由软的金属制成有的原子核会同时裂变,而另外一些却不会第5节翻译练习8Anothermethodisavailabletoincreasethesystemcapacity.Heatisalwaysbeingtransferredinonewayoranotherwherethereisanydifferenceintemperature.凡有温差的地方,热都会以这样或那样的方式传输还有另一种可增加系统容量的方法第5节翻译练习9Somemetalsburnmorereadilythanothers.Tospecifyadistancewemustusesomeunitoflength.Whenanobjectiswarmerthanthesurroundingregionitlosessomeofitsheatbyradiation.Theparticlesrequiresomeadaytoreachtheearth.为了确定距离,我们必须使用某种长度单位有些金属比另一些金属更容易燃烧当一个物体比周围环境热时,该物体会通过辐射失去它的一些热量这些粒子大约需要一天的时间才能到达地球
4.6it及其句型的译法第6节翻译练习1Itmovesorrotatesbyafixedamounteachtimeanelectricalpulseisappliedtoit.Tohelpavoidinformationoverloaditvirtualconvergencewilldothisintelligently.Theearthrotatesasittravelsthroughspace.Ascurrentflowsthroughaconductoritsetsupamagneticfield.为了避免信息过载,它(虚拟连接)将会智能化地进行操作对它每加一个电脉冲,它就移动或旋转一个固定的量地球在空间运行时,它还要自转电流通过导体,便产生磁场第6节翻译练习2Itisa$12-billionindustrywhosefactoriesnumberinginthehundredsarefoundallovertheworld.Itistwentymetersinheight.那个行业资金达120亿美元,工厂有上千家,遍布世界各地高度为20米第6节翻译练习3Itisveryfartotheairport.Itisraininghard.到机场很远雨下得很大第6节翻译练习4Itisrecommendedthatthescrewbeusedtoincreaseaccuracyofmeasurement.Byusingalaseritispossibletothrowverylargeandverycleartelevisionpicturesontoascreen.Itwaspointedoutthatwhiletheleadobtainedfromthedisintegrationofradiumpossessedallthecharacteristicsofordinaryleaditdifferedfromitinatomicweight.使用激光器,可以将很大很清晰的电视图像投射到屏幕上建议使用螺杆调节,以提高测量的精确度前已指出,虽然由镭蜕变而获得的铅具有普通铅的一切特性,但其原子量与普通铅不同第6节翻译练习5Itnecessitatescarefuldesignoftheapparatustogetridoftheheat.Itisunknownwhentobegintomaketransportabletransformers.Itisinterestingtocomparetheenergyneededtoplaceasatelliteinorbitwiththeenergythatwouldberequiredtocauseittoescape.什么时候开始制造移动式变压器还不知道除热需要对设备进行仔细设计把一颗卫星送入轨道所需的能量和使卫星脱离地球所需要的能量进行比较是很有意思的第6节翻译练习6Itusedtobethoughtthatwhenyouseeawordandspeakitseveralstagesofprocessingareinvolved.Itmustberememberedthattheconditionmaybesilentuntilhaematemesismelaenaorperforationoccurs.Itisknownthatelectroniccomputersplayanimportantpartinscienceandtechnology.大家必须记住,在呕血、黑便,或穿孔发生之前,该病可能无症状过去人们常常认为一个词从看见到念出来包括好几个处理阶段我们知道,电子计算机在科学和技术方面起着重要作用第6节翻译练习7Itfollowsthatanyformofpreheataddstothewelder’sdifficultiesandcausesdiscomfortparticularlywhenweldingathighpreheattemperaturelevelsinsidevessels.ItcanbeconcludedthattemperaturesonthesurfaceofVenusistoohotforlifeasknownonearth.Ithadbeencalculatedthatactualerrorprobabilityforthevaluewasoftheorderof
0.5percent.由此可见,任何形式的预热都会增加焊工的困难,使他们身感不适,在容器内高温预热下施焊时尤其如此可以断定,金星表面的温度过热,地球上的生物是不能适应的据计算,这个数值的实际误差概率约为
0.5%第6节翻译练习8Itmakesnodifferencewheninducingane.m.f.whichmovesthecoilorthemagnet.Itisessentialthatthebodyofthemachineiseffectivelyearthed.在感应出电动势时,是线圈运动还是磁铁运动,这没有区别这机器的机身必须有效接地,这一点十分重要第6节翻译练习9Theheatingeffectmakesitpossibletoproducethelight.Wefinditpossibletotransforma.c.intod.c.byusingarectifier.Wethinkittruethatthehumanbodyisalsoagoodconductor.热效应使产生光成为可能我们发现能用整流器将交流电变成直流电人体也是一种良好的导体,我们认为这点是正确的第6节翻译练习10Itisthevoltmeterwhichweusetomeasurethevoltage.Itisthroughthisinterfacethatthesubstationoperatormustcontrolandmonitortheentiresubstation.ItwasnotuntilIcameinthathebegantorepairtheoldgenerator.我们用来测量电压的就是伏特计变电站运行人员正是通过这个界面控制和监视整个变电站的直到我进来,他才开始修理那台老式发电机Itwasnotuntilthe19thcenturythatheatwasconsideredasaformofenergy.直到19世纪,热才被认为是能的一种形式第4章总复习题Theriseintemperaturecouldnothavehappenedofitself.Betheshapeofabodycomplicateditispossibletofindoutitsvolume.Themoreenergywedesiretosendthehigherwemakethevoltage.Themosttypicalhumanlikecharacteristicofarobotisitsarm.温度上升不可能是出于自身的原因不论物体的形状如何复杂,人们均可求出它的体积要求输送的电能越多,就得使电压升得越高机器人最具人性化的特点就是它的机械臂InourstudiesoftheimplicationsfortheFirstLawwewereabletoseetheimportanceofthedistinctionbetweenstateandpathfunctions.Thefirstjobofanelectrontubeistogettheelectronsapartfromtheirnuclei.Thattypeofturbineusuallyrotatesataverylowspeed.那种汽轮机通常以非常低的速度运转我们研究第一定律时,可以明白区分状态函数和路径函数的重要性电子管的第一项工作就是使电子与其原子核分开Smallobjectssuchasdustparticlesandwaterdropletsfallonlysmalldistancesbeforelosingmostoftheiracceleration.Thesamehashappenedtothecentralcontrolsystem.There’shardlyanyroomforanyimpuritiesinsuchamicrofiber.中心控制系统也发生过同样的事故小物体,比如尘粒和水珠,仅仅下落了一小段距离后便失去了其大部分的加速度在这种微纤维中,杂质几乎没有存在的可能HisinstanceswereLennardandStarkbothofthemwereNobellaureatesbutlaterbecameferventfollowersofHitler.Theprimacyfunctionofaregulatoristosupplyconstantpressuretoeachdevice.Thebestuseoftheseequationsisincheckingthetheoreticalanalysesusingtheotherapproaches.他举出勒纳德及史塔克为例子这两个人都得过诺贝尔奖,但后来却成了狂热的希特勒信徒这些方程式最大的用处是可对采用了其他方法的理论分析进行检验调节器的基本功能是给每个装置提供稳定的电压Itisdesirabletocharacterizeelectricalnoiseasaccuratelyaspossible.Itisknownthatlocalweathercanbeaffectedwithinafewdaysbymeteorologicalconditionsthousandsofmilesawayfromhere.需要尽可能准确地表征电噪音我们知道,当地的天气在几天内会受到几千英里以外地区气象状况的影响
5.1数词的译法第1节翻译练习1Liquidbromineboilsat58°Catwhichtemperatureitchangesintoareddish-browngas.Movetothenextoperationafterthevoltagereaches150V.Testshaveshownthattheenergysavingcanriseabout40percent.液态溴在58摄氏度时沸腾,在这个温度它变成红褐色的气体等电压到了150伏时,进行下一个操作试验证明,能量节约可增加40%左右第1节翻译练习2Ofmanythousandssparepartsdoesnotcomeuptothestandardbutone.Alotofcountieshavesetuppowerstationschemicalfertilizerplantsandahundredandoneotherfactories.Theperiodictablecontainsmorethanonehundredchemicalelementsbelongingtoeightfamilies.在几千个备件中,只有一个不合格许多县已建立了发电站、化肥厂以及许多别的工厂元素周期表由属于8个族的100多个化学元素组成Thesematerialsbecomequitesoftandflexiblebelow150°C.Anincreaseintheoxygencontentofcoalby1%reducesthatcalorificvaluebysome
1.7%.Nearly25neurotransmittershavebeenfoundsofar.这些材料在150摄氏度以下变得十分柔软、易于弯曲煤的含氧量每增加1%,其热值就下降约
1.7%迄今为止,已经发现了大约25种神经传递素第1节翻译练习3Withtheresultofautomationproductivityhasincreasedby5timesinthatfactory.Thesalesofindustrialelectronicproductshaveincreasedtosixtimes.Theoutputofthemachinetoolshasmultipliedfourtimes.Thecurrenthasincreasedbyafactorofthree.由于自动化的结果,那个工厂的生产率提高到5倍工业电子产品的销售额增加了5倍机床产量增加了3倍电流增加了2倍第1节翻译练习4Thistypeoffurnaceuses4timesmoreelectricitythanthattypedoes.Thisrodis4timeslongerthanthatone.Theoxygenatomisnearly16timesasheavyasthehydrogenatom.这种炉的耗电量是那种炉耗电量的4倍这根杆比那根长3倍氧原子的原子量几乎是氢原子量的16倍Theatomicweightofheliumisfourtimesheavierthanthatofhydrogen.Inrollingbearingthestartingfrictionisabouttwicetherunningfriction.氦原子量比氢原子量重3倍滚动轴承的启动摩擦大概是转动摩擦的2倍第1节翻译练习5Theleadsofthenewcondenserareshortenedbysixtimes.Theoperationofcostdecreasedbyfivetimes.Thelossofelectricitywasreducedbyafactoroffour.Thepipeisfourtimeslighterthanthatone.新型电容器的引线缩短了5/6成本运行降至1/5这根管子重量是那根的1/4电损减少了3/4第1节翻译练习6Weldstrengthcanbeincreasedby45percent.Testshaveshownthattheenergyconsumingcanbereducedby30percent.Thelossofenergyhasbeenreducedtolessthan10percent.焊接强度可增加45%试验证明,能量消耗可减低30%能量损耗可减至不足10%Itsgrainoutputwas18percenthigherthanthatin
1998.Thesteeloutputis30percenthigherthanthatoflastyear.其粮食产量比1998年高出18%钢产比去年增加了30%第1节翻译练习7Tentoonetheexperimentisunlikelytoproducegoodresults.Thesefiguresshowthattheimprovementofmolecularrefractioniswithinafactoroften.十有八九,这项试验不可能得出好的结果这些数字表明分子折射度的改进值为一个数量级
5.2形容词的译法第2节翻译练习1Suitabletreatmentshallbegivenassoonaspossibletoavoidhydrogenembrittlement.Complexcomputersystemsarepronetosoftwarehitches.Thepartsmustbeverystrongsothattheymaynotbreakinuse.Thiskindofsteelbecomesveryhardandverybrittlewhenhardened.尽快予以适当的处理,以免氢蚀脆化复杂的计算机系统容易出现软件故障零件必须十分坚固,才不会在使用中破损这种钢淬火后就变得很硬很脆第2节翻译练习2Hydrogenisaboutone-fourteenthasdenseasair.Heliumisaverylightgasonlytwiceasheavyashydrogen.Icefloatsbecauseitisnotasdenseaswater.氢的密度大约是空气密度的1/14氦气是一种很轻的气体,重量仅为氢气的2倍冰浮起是因为它的密度比水的密度小第2节翻译练习3Inthethermosciencesareathemechanicalengineerisconcernedwiththermodynamicsfluidmechanicsandheattransfer.Thisinalargemeasureisresponsibleforthehighaccuracyobtainablefromsuchsystems.Thetransmissionratioisdependentupontheratioofthenumberofteethofthemeshinggearwheels.在热学领域,机械工程师关心的是热力学、流体力学和传热学在很大程度上,这是从这类系统中获得高精度的原因传动比取决于两个啮合齿轮的齿数比Oncetheengineisunderwaytheseauxiliariesareturnedoff.发动机一旦启动,这些辅助设备就关闭了第2节翻译练习4Recentdiscoverieshavebeenmadeconcerningthepeculiarpropertiesofcertainsemiconductors.Researchanddevelopmentisofparticularimportancetoaerospaceindustry.Incopperandmostpuremetalsthereisanappreciableincreaseinresistancewithanincreaseintemperature.最近,对于某些半导体的奇怪特性有一些发现研究和发展对航空航天工业非常重要在铜和大部分纯金属中,随着温度的升高,电阻也会明显增大Oneofthedrawbacksoftheearlylaserswastheirinabilityofcontinuousoperation.Thesemetalionsinterferewithelectronflowandcauseagreatdecreaseinelectronmotion.Lubricatingoilsareusedtoensurethesmoothrunningofthemachine.早期激光器的缺点之一是它不能连续工作这些金属离子阻碍电子流动,引起电子运动大幅减弱使用润滑油是为了确保机器正常运转第2节翻译练习5Themostcommonapplicationforbearingisthesupportofarotatingshaftthatistransmittingpowerfromonelocationtoanother.TheWorldWideWebisauniquemediumforcommunicationandforpublishing.轴承最常见的应用是支撑旋转轴将功率从一处传至另一处万维网是一个独特的通讯和出版媒体第2节翻译练习6Apracticalmeansoftransferringgeothermalenergyistoconvertittoelectricpower.Anelectronifmovingproducesamagneticfield.将地热能转变成电能是输送这种能量的一种切实可行的办法电子如果运动,就会产生磁场第2节翻译练习7Needlebearingshaveahighloadcapacity.Considerableeffortmustbeexpendedtoensureconsistentblastvolumehumidityandtemperature.滚针轴承的承载能力大还要在确保风量、湿度和温度稳定方面做出相当大的努力第2节翻译练习8Thegearteethshouldhavethestrengthsufficienttooperate.We’lldoeverythingpossibletoimprovethesupplyofelectricity.Wehopeeverythingreadyfortheoperation.Scientistshavefoundamethodofmeasurementsuitableformostislandwatersandcoastalareas.齿轮的齿必须具备足够的运转强度我们将尽一切努力来改善电力供应我们希望一切在开工之前就绪科学家们已经找到了一种适合大多数岛屿的近海和沿海地区的测量方法Coalisakindoffuelsuitableforpowergeneration.TheonlytransformeravailableisproducedinShanghai.煤是一种适合发电的燃料唯一可用的变压器是上海产的第2节翻译练习9Theresistanceoftheloadistoohighfortheamplifier.Forthisreasontheswitchingsignalshouldbenosteeperorlargerthannecessary.Thecapacitytostorewaterintheirleavesistypicalofdesertplant.Heisquitefamiliarwithstatefunction.负载的电阻对于放大器来说太高因此激励信号的斜率及宽度不应超过所要求的数值在叶子中储存水的能力是沙漠植物的特性他非常熟悉状态函数第3节翻译练习1Desertedsoilsaresparselycoveredwithshrubsandgrass.Therelationshipsusedarebrieflyoutlined.荒漠上稀疏地覆盖着灌木丛和杂草这些用到了的关系已简要地概括出来了
5.3副词的译法第3节翻译练习2Theresultingfluxisconfinedessentiallytothering.Actuallyandmetaloralloycanbecastbyprecisioncasting.Normallythewholemassoftheatomisconcentratedinthenucleus.所产生的磁通基本上被限制在环内实际上,任何金属或合金都可以进行精密铸造在正常情况下,原子的整个质量都集中在原子核里第3节翻译练习3Admittedlythetermtemporalcoherenceseemstoimplyaneffectwhichisexclusivelytemporal.Themostimportantadvantagesofrollingbearingsoverslidingbearingsisthemostcompleteeliminationoffriction.不可否认,时间相干性这个术语似乎意味着一种只属于时间的效应滚动轴承优于滑动轴承的最重要的优点在于几乎完全消除了摩擦第3节翻译练习4Wearecertainthatneutronsactdifferentlyfromprotons.Todetectgasesasampleofaircanbeanalyzedchemically.Slopesorientateddifferentlyreceivedirectsolarradiationindifferentamounts.我们确信中子的作用和质子的是不同的为了检测各种气体,可以对空气试样进行化学分析朝向不相同的山坡,直接接收到的太阳辐射量是不同的第3节翻译练习5Thesaltsshouldbeheatedelectricallyifpossible.Themethodsofcontrollingpestschemicallyoftenhaveundesirablesideeffects;forthisreasonitislikelythatthemethodsofcontrollingbiologicallywillbeappliedincreasinglyinthefuture.Evaporationtakesplaceonlyatthesurfaceofaliquid;boilingtakesplacethroughouttheliquid.如果可能的话,这些盐应该用电来加热用化学品控制害虫的方法常有不良的副作用,因此将来会越来越多地采用生物学方法蒸发只是发生在液体表面,沸腾发生在液体各处第3节翻译练习6TheCPUalsocontrolstheflowofdatatoandfromtheperipheraldevices.Itisalsopossibletocheckthetemperaturedistributionatthetopoftheburdenalthoughtheburdenatthetopofthefurnaceisnotevenlydistributed.Thereisalsoanincreasedexcretionofnitrogeninorganicphosphorusandsodiumchloridesalt.CPU还控制着流向和来自外部设备的数据流尽管炉顶炉料的分布方式是不均匀的,但炉顶炉料的温度分布也还是可以检测的推拿还促进氮、无机磷和氯化钠(盐)的排放第3节翻译练习7Arelativelysmallexplosionwouldbeenoughtosendashipoffataveryfastrate.Whenthecoreofthiscloudbecamedenseenoughgravitytriggeredthecollapseofitsinnerlayers.Satellites---somelargeenoughtobeplanetsintheirownright---eitherformedalongwiththegiantsorwerecapturedlater.一次较小的爆炸就足以将飞船以极快的速度发射出去当这个分子团的核心变得十分稠密时,重力引起分子团的内层崩溃至于卫星,有些大的足以称得上行星,它们或是与这些巨大的行星同时形成,或是后来被猎获的第3节翻译练习8Thewattisasmallunitofpowersoweusethekilowattinstead.Insteadofworkingwiththespacevariableforelectricfieldintensitywecanworkdirectlywithvoltage.瓦特是一个很小的功率单位,因此我们就改用千瓦代之我们可以直接用电压来代替电场强度这个空间变量第3节翻译练习9TheexperimentalresultwasjusttheoppositeofwhatIhadexpected.Theintroductionoflaserintoindustryhasonlyjustbegun.实验结果与我预料的刚好相反激光用于工业还仅仅刚开始第3节翻译练习10Neverlaytoolsorworkpiecesonthewaysofalathe.Manhasnevermadeamachinethatofitselfwillcontinueinastateofuniformmotion.Uptonowatomicenergyhasneverbeenusedforaircraftpropulsion.绝不要把工具或工件放在车床的导轨上人类从未制成过一台能自行永久保持匀速运动状态的机器到目前为止,原子能从来没有被用于飞机的推进第3节翻译练习11Anelectriccurrentisonlyashiftingofelectricity.Whatwecallmassisonlyanothermanifestationofenergy.Onlywhenanobjectmovesisworkdone.电流仅仅是电的移动我们所说的质量只是能的另一种表现形式物体只有移动时才做功第3节翻译练习12Gravitykeepsthesatelliteinorbit.Otherwiseitwoulddriftoffintospace.Hisinspectionofthetransmissionlinesrevealedsomepossiblefaultsthatmightotherwisehavebeenoverlooked.引力使卫星保持在轨道上,否则卫星就会偏离而进入太空他对输电线路进行检查,查出了一些故障,否则这些潜在的故障就会被忽视第3节翻译练习13Inamathematicalsensetheimpulseresponseisarathersophisticatedconcept.Processdependsonidentifyingradiostarswithsomekindofobjectemittingvisiblelight---butradioastronomerscangivetheiropticalcolleaguesonlyratherimprecisedirectionsastowheretolook.Theoperationofourgeneratingunitwasnobetterbutratherworse.从数学意义上讲,冲量反应是个相当微妙的概念进一步的进展取决于能否确定射电星是一种能发射可见光的天体,然而射电天文学家只能给光学天文学家提供很不精确的观测方向我们机组运行的情况没有见好,相反更糟了Thetemperaturedidnotgoupasonehadexpectedbutratherwentdown.Theyareencouragedindesigningaturbineratherthanrepairingit.Indecidingwhereanairplaneactuallyisintheskywebelieveoureyesratherthanourears.温度没有像人们预料的那样上升,反而下降了他们从事涡轮机的设计工作,而不是修理涡轮机要判断飞机在空中的确切位置,我们与其相信自己的耳朵不如相信自己的眼睛第3节翻译练习14Justasthefeed-watersupplysystemcanbecontrolledsothecoalhandlingequipmentcanalsobecomputer-controlled.Itisforthisreasonthatsomuchcarehastobegiventotheburdenpreparationbysinteringandbytheblendingoffluxesandcoke.Somanydeviceshaveutilizedtheseprocesses.正如给水系统可由计算机控制那样,输煤设备也可以这样做正因为如此,必须通过优良烧结以及助熔剂和焦炭来精心准备高炉的炉料如此之多的装置现已采用了这些工艺第3节翻译练习15Attentionisgiventothetransformertoo.Toomanywomenignoretheamountofirontheytakein.Suchparticlesarefartootinytobeseenwiththestrongestmicroscope.Hardenedsteelistoohardandtoobrittleformanytools.同时也注意变压器太多的女性忽视了自己摄入的铁离子含量这种粒子太小,即使用最高倍的显微镜也看不见硬化钢太硬、太脆,对许多工具的制作都不适宜第3节翻译练习16Manynaturalphenomenayetremaintobeinvestigated.Thecauseofthiswearhavenotyetbeenestablished.Ifthetemperatureishightheresistanceofawirebecomesyetgreater.尚有许多自然现象有待研究这种磨损的原因尚未查明如果温度升高,导线的电阻会更大Thiscouldturnouttobeourbiggestmistakeyet.Thisisthebiggestundergroundlakeyetdiscovered.这是我们到目前为止所犯的最大错误这是迄今已发现的最大的底下湖
5.4形容词和副词比较级的译法第4节翻译练习1Theroadsinourpowerplantarewithanewkindofmaterialthestrengthofwhichisasgreatasthatofconcrete.Metalsdonotchangetheirformaseasilyasplasticbodiesdo.我们电厂的道路是一种新材料铺设的,这种新材料的强度与水泥的强度一样高金属不像塑料物体那样容易变形第4节翻译练习2Thismaterialcanwithstandhigherstressesunderrepeatedloading.Givenahighercapitalcostforelectricbusesthecashgrantpayablewouldbehigherforaconventionalvehicle.Ifonehasanattitudeofrespectfortheequipmenttheendproductwillbemoresatisfactory.这种材料在交变载荷下可以承受较高的应力即使电瓶巴士投资成本高于传统车辆,传统车辆应支付的现金补贴也会更高如果人们对生产设备持尊重态度,那么其生产出的成品也会更加令人满意第4节翻译练习3Therightgeneticmaterialweightforweightcanbemorevaluablethanpreciousmetalsandjewels.Threeofthegiantplanetsradiatemoreheatbackintospacethantheyabsorbfromthesun.恰当的遗传物质,就其重要性来说,要比贵金属和珠宝更有价值巨大的外层行星中有三颗射向太空的热量超过它们从太阳那里吸收的能量第4节翻译练习4Evenquitesmallamountsofsomeimpuritiescanmakecopperamuchpoorerconductorofelectricity.Aluminumandcopperarefarmorecorrosion-resistantthanordinarysteel.甚至很少量的杂质都可能会使铜成为性能差得多的导电体铝和铜的抗腐蚀能力比普通钢高得多第4节翻译练习5Nuclearenergyisbeingusedmoreandmorewidely.Moreandmorenuclearpowerstationsarebuiltup.核能用得越来越广泛了建设了越来越多的核电站第4节翻译练习6Thegreaterthebearingloadtheshorterwillbethelifeofthebearinginrevolutions.Thefartheroutthelineofthemomentumextendsthegreatertheangularmomentum.Thegreaterthecross-sectionalareathegreaterthestrengthwillbe.轴承的载荷越大,其以转数为单位的寿命就越短动量作用线伸展得越远,角动量就越大截面越大,强度越大
5.5形容词和副词最高级的译法第5节翻译练习1:Polyacetyleneisthesimplestpossibleconjugatedpolymer.Painisthemostprominentsymptomofsurgicaldisease.聚乙炔可能是最简单的共轭聚合物疼痛是外科疾病最突出的症状第5章总复习题Thisseemstoindicatethatfurtherresearchwouldbenecessary.Ana.c.motorissimilarinconstructiontoad.c.motor.Naturalenvironmentcanbeeasilyruinedbyinappropriateexploration.Negativechargesaremovingcounterclockwise.这似乎表明进一步研究的必要性交流电动机与直流电动机结构相似开发不当容易毁坏自然资源负电荷按逆时针方向流动Theaveragevalueofvoltagecanbemeasuredpointbypoint.Theproblemofmaterialsiseasedbythelowerboilingpoint.Asaresultalthoughthereisminimalfrictionpresentalubricantisstillabsolutelyessential.Removalprocedureforleft-handandright-handcycliccylindersisessentiallythesame.因此,虽然有很小的摩擦,但润滑剂仍旧是非常必要的电压的平均值可以逐点测量由于沸点较低,材料问题容易解决左右两边循环气缸的拆卸步骤基本上相同Substantiallyanthecyaninthepigmentthatturnsleaves---andapples---redisproducedbysugarsthatremainafterthenutrientsarechokedoff.Massagewillaffectmusclesthroughoutthebody.Inthistestthemajorpartisbackedoffelectrically.Itisalsogoodforshockandimpactloads.Thetermminimumlifeisalsousedtomeanratinglife.在此项实验中,主要部分被电补偿本质上,使树叶和苹果变红的色素——花色素苷是营养去除后剩余的糖分产生的它还适用于振动和冲击载荷推拿将会对全身的肌肉组织产生影响最小寿命这个术语也指额定寿命Usuallya2cmadjustmentofthemachineisenoughtobringthepressurebacktonormal.Statisticsisarathermodernbranchofmathematics.Computersprovidethemeansforgreaterspeedandaccuracyinworkingwithideasthanhadpreviouslybeenpossible.Lessthanaquarteroftheenergyofahumanengineisconvertedintomechanicalenergy.Hydrogenisthelightestgasitsdensitybeing
0.0894g/l.统计学是一门相当新的数学分支人体发出的不到1/4的能量转变为机械能计算机处理意念时所提供方法的速度和精确度都超过了以往所能达到的水平氢是最轻的气体,其密度为
0.0894克/升通常,把机器调整2厘米就足以使压力恢复正常
6.1介词的一般译法第1节翻译练习1Ingeneralmanservesasthesourceofinfectionwhileanimalsactassuchonlyoccasionally.Anindustrialrobotsharesmanyattributesincommonwithanumericalcontrolmachinetool.一般来说,人可作为感染源,而动物只是偶然如此工业用机器人与数控机床有许多共同的特性第1节翻译练习2Withnon-changeovercontrolboththeboilerplantandthechillerplantoperatetoprovidesimultaneousheatingandcoolingthroughouttheyear.Theonlineservicedeliverssubstantiallymorevaluetoourglobalaudienceofe-businessprofessionalsinthechemicalplasticsandalliedindustries.Thisdevicecanmimicphotosynthesistoproduceusableenergyfromsunlight.采用非转换控制,锅炉设备和制冷装置都在运行,全年可同时供暖和制冷该网络服务主要向全球从事化学、塑料及相关工业的专业电子商务用户提供更有价值的服务这种装置能够模拟光合作用,利用阳光产生可用的能源第1节翻译练习3Thelongitudinalaxisoftheturbinegeneratorisperpendiculartotheaxisofthesteamgenerator.Intherightconditionsmembranesareself-assembling.Windingofthespringinducesresidualstressesthroughbending.汽轮发电机的纵轴与锅炉轴线垂直当条件适宜时,细胞膜会自行聚集卷绕弹簧时因为弯曲引起了残余应力第1节翻译练习4Ifleakageoccursaroundoutputshaftreplacesealandpacking.Sotheygiveoffastrongersignaltosensitiveradiationdetectorsmountedoverthesubject’shead.如输出轴周围漏油,应更换密封件及填料因而它向安装在受试者头部上方的灵敏的辐射探测器发出的信号比较强第1节翻译练习5Itiscustomarytouseelectromagnetsratherthanpermanentmagnetsforthefield.Thisflatscreentechnologyeliminatescurvatureonthescreensurface.Allthechargeonaconductorliesonitssurface.通常磁场用的都是电磁铁而不是永久磁铁这种纯平面技术可以消除屏幕表面的弯曲导体的全部电荷都在其表面
6.2介词短语的译法第2节翻译练习1Foreaseofassemblyandremovalofthewheelstheouterracesarepress-fittedinthewheelhubs.Withthelengthmuchgreaterthanitswidththecoiliscalledsolenoid.WithonlyabouthalfasmanymovingpartsasaconventionalengineaWankelisonlyhalfthesizeandweightandalmostcompletelyvibrationless.为了便于车轮安装和拆卸,把外套圈压入配合到轮毂里如果长度远远超过了宽度,这种线圈就称为螺线管由于其运动机件数几乎仅为一般发动机的一半,汪克尔发动机只有一般发动机的一半大、一半重,而且几乎完全没有振动Withoutanelectricfieldappliedadielectricatomissymmetrical.Despitechangesintheloadthevoltageappliedtoitremainsfairlyconstant.Formoreinformationontheimprovementswe’vemadescrolldowntoNewFeaturesFunctionality.如果没有外加电场,电介质原子是对称的不管负载如何变化,加在负载上的电压都仍然相当稳定要想对我们的改进有更多的了解,请往下看“新特点与新功能”第2节翻译练习2Singularityfunctionsdonotoccurinphysicalsystems.Afairamountoftheoreticalandexperimentalworkhasbeendevotedatthisagencytoabetterunderstandingofnon-stationaryaerodynmics.物理系统不存在奇异函数该机构为更好地了解非定常气体动力学作了大量的理论研究和试验工作第2节翻译练习3Animalsarealwayslosingcarbonbyrespirationasagainstplantsalwaysgainingcarbon.Themosteffectivemethodofreducingfrictionistouserollingfrictioninsteadofslidingfriction.动物通过呼吸排除碳,而植物却吸收碳减少摩擦力的最有效的方法是采用滚动摩擦,而不是采用滑动摩擦第2节翻译练习4Theshapeoftheelectronspectruminbetadecayisnotdominatedbypropertiesofthematrixelement.Pressureinaliquidisatrightanglestothewallsofcontainer.β衰变的电子谱的形状不取决于矩阵元的性质液体的压力与容器壁垂直第2节翻译练习5Hysteresisenergyisausefulbasisfortheestablishmentoffailurecriteriainfatigue.Physicalchemistryappliesthemethodsofphysicstothestudyofchemicalsystems.在建立疲劳破坏准则时,迟滞能量是一个有用的依据物理化学是应用物理学的方法研究化学体系
6.3常用介词的译法第3节翻译练习1Littleinformationisgivenabouttheoriginoflife.Abasicchangeinthinkingaboutforceandmassisrequired.Fluoridedamageisgenerallyrestrictedtoareasaboutmanufacturingplants.Thevacuumwascreatedabouttheexit.关于生命起源方面的资料极少对于力和质量的看法需要做根本的改变氟化物的危害一般仅限于制造厂附近在出口附近产生真空第3节翻译练习2Allofitscircuitelementsarebondedtogetherafterbeingmanufactured.Linereamsnewbushingsafterinstallation.Afteralllogiceventshavebeencompletedtheautomaticcontrolunitinitiatesthemachineaftertheinstruction.将所有的电路元件在制成之后都连结在一起安装后对新轴套绞同心孔在所有的逻辑事件完成之后,自动控制器按照指令再次启动该机器Thosemachinesaremadeafterthemodel.Afterallitschangeableformsenergycanneverbedestroyed.那些机器是按该模型制成的尽管能的形式是可以改变的,但绝不会消失第3节翻译练习3Workinginstrumentsareverifiedforcalibrationagainstreferenceinstruments.Thecurrentinatransmittingantennawhenplottedagainsttimeisusuallyasinewave.Theprocesswasagainstanybasiclawsofphysics.Forceisnecessarytodriveanelectriccurrentagainstaresistance.工业用的仪表要根据基准仪表来校验其刻度将发射天线中的电流相对于时间来描述出来,常是一正弦波该过程违背了物理学的基本原理驱动电流克服电阻需要有电动势Oneofthechiefusesofzincistoprotectthesurfaceofironagainstrust.Lighteningrodsareusedtoprotectelectricaldevicesagainstlightening.Itisnecessarytopreventinductionmotorsagainstoverloadandundervoltage.Theadvantagesanddisadvantagesofeachalgorithmhavetobeweightedagainsteachotherinthelightoftheparticularapplication.锌的主要用途之一是防止铁表面生锈避雷针用来保护电器设备不受雷击必须保护感应电动机,防止过载及欠压每一种算法都必须根据具体应用相互对比才能权衡其优劣第3节翻译练习4Thesecondphaseoftherestorationprojectwillbetolaydownastabilizationringaroundthetower’sfoundation.Theseparatingforceonthemillwascalculatedtobearound10million1b.Thearchdamiseconomicalinnarrowcanyonswherethetopchordlengthisaroundtwotothreetimestheheightofthedam.修复工程的第二阶段是在塔基周围建造一环形稳固基此轧机的轧制力量估计大约一千万磅左右截面越大,强度越大第3节翻译练习5Eachobservationcouldbeweightedinverselyasthedistanceorasthesquarerootofthefrequency.Iftheelectriclinesareparalleltotheearththewaveisreferredtoashorizontallypolarized.每次观测可以倒过来加权,作为距离或频率的平方根如果电力线与地面平行,其电波就称为水平极化电波第3节翻译练习6Atthebeginningofitsoperationthisturbineisonlyabout50percentefficient.Itisusualtoprovideaflowmeteratthecolumnoutlet.Asmallholeisprovidedatthelockringgroovetofacilitateremovalofthelockring.在开始运行的时候,这台涡轮机的效率只有50%在柱子出口处常常要安装一个流量器为使锁定环拆卸方便,可在其沟槽内开一小孔Theshuntmotoroperatesnearlyatconstantspeed.Womenofchild-bearingageareatgreatestrisksincetheirmonthlybleedingisamajorsourceofironloss.并励电动机差不多恒速运行育龄女性危险最大,因为月经是铁流失重要原因之一第3节翻译练习7Andoffshoredrillingismadepossiblebyusinghugequantitiesofgaseousnitrogenandoxygentoprovidealivableatmospheredeepunderwater.Everymetalpossessescertainpropertiesorcharacteristicsorqualitieswhichwecanfindbyexperiment.Allmaterialsaredeformedtosomeextentbytheapplicationofanexternalforce.用大量的氮气和氧气形成在深水中能够生活的环境,才有可能进行海底石油钻探每一种金属都具有某些性能,或特性、性质,而这些我们可以通过实验检验出来所有材料多少都会由于外力而变形(练习8用法)NdBytheLawofUniversalGravitationallbodiesattracteachother.Bythistheorywecanexplainthephenomenonforwhichtheoldviewofmatterdidnotaccount.按照万有引力定律,一切物体都相互吸引根据这一学说,我们就能解释旧的物质观没有说明的现象第3节翻译练习8Themachinetoolisdirectlydrivenbythemaindrivemotor.Thepituitaryglandisconstitutedbytwolobes.Theenergypossessedbyanobjectbyvirtueofitsmotioniscalledkineticenergyorenergyofmotion.Theproductioncapacityhasgreatlyincreasedbythedevelopmentofthecontrolofmanufacturingprocessesbycomputers.机床由主电机直接启动物体由于运动而获得的能量称为动能,或称为运动能量由于采用了计算机控制制造过程,因而生产能力大大提高垂腺体由两个叶组成第3节翻译练习9Wemaynothaveeliminatedcigarettesmokingcompletelybytheendofthiscentury.Thefacultylinemustberepairedbythetimeofthesummerharvest.Thecurrentinaninductorlagsthevoltageby90°orwhatisthesamethingthevoltageleadsthecurrentby90°.Theexpertscalculatethatthiswillstraightenupthetowerbyseveralcentimeters.到本世纪末我们或许还不能完全消除吸烟现象夏收之前,故障线路必须修好根据专家们的计算,这将使斜塔取直几厘米电感器中的电流落后于电压90°,或者说,电压超前于电流90°第3节翻译练习10ByhPawemeananinternationalstandardizedpressureunit.Byconductivitywemeantheabilitytoconductanelectriccurrent.所谓百帕,是国际上通用的表示气压的单位所谓导电率,是指传导电流的能力Nd第3节翻译练习11Theelectricdrivesystemismadedetachableforeaseoftransportationandinstallation.CFCsandotherozone-depletingchemicalswerefirstmass-producedinthe1950sforuseasrefrigerantsindustrialsolventscleaningfluidsandagentsinmakingfoamproducts.Thesedataarethebasisforimportantdecisions.Theywillbuildtwopowerplantsherewhichcanmeetthedemandsforpowersupply.为了便于运输和安装,电力驱动系统做成可拆式20世纪50年代,氟里昂和其他消耗臭氧的化工产品首次批量生产,它们主要用作制冷剂、工业溶剂、清洗液以及制造泡沫产品的制剂这些数据上做出重要决策的依据他们将在这里建两座电厂,这样便可以满足对电力的需求Nd第3节翻译练习12Thetemperaturewastoohighfortheboilertowithstand.Avisualinspectionmustbedonecarefullyforthematerialsespeciallyforthosetobeusedinfabricationofpressurevessels.Forthisreasonbeverycarefulwhenyoutakeantibiotics.Thefirstpassengerscametogroundnonetheworsefortheirexperience3000metersfromtheirstandingpoint.温度提高,致使锅炉承受不了必须对材料仔细进行外观检查,对制造压力容器所用材料尤需如此由于这个原因,当你用抗生素时务必非常小心第一批乘客在离出发点3000米处着陆,并没有因这一遭遇而发生不良反应Nd第3节翻译练习13Makewaterdodutyforalcoholasasolvent.Theysucceededinsubstitutingasyntheticrubberforthenaturalrubber.Electricitycompensatesforbarometricpressureaswellassystempressurevariations.用水代替酒精当溶剂用他们在用合成橡胶代替天然橡胶方面取得了成功用电补偿大气压力和系统压力的变化NdThediseaseragedthroughthecityformonths.Themixturewascuredatroomtemperaturefor8-14days.这种疾病在这座城市猖獗了几个月混合物在室温下需熟化8-14天第3节翻译练习14Foralltheirgreatstablenessunderordinarycircumstancesinsulatingmaterialsmaychangeradicallyincharacteristicsunderextremeconditionsofvoltagestressortemperatureorundertheactionofcertainchemicals.Forallitsinvisibleshieldtheozonelayercanbemeasuredinanumberofways.Forallouradviceheinsistsoncarryingoutignitionexperiment.尽管在正常的情形下绝缘材料的性能很稳定,但在极端情况下,比如电压过高、高温或在某种化学物质作用下,绝缘材料的性能会遭到完全破坏尽管臭氧层是一种不可见的保护层,但还是有多种测量它的方法尽管我们劝阻他,他仍然坚持要进行点火实验Nd第3节翻译练习15Thisreducestheresistancetocurrentflowingfromthewirethroughtherubbertocopperstripsbelowthetubes.Ausermayjumpfromonedocumenttoanotherinanonlinearassociativeway.Fromtheinformationinthistablewecaneasilycomputeanestimateofthevalueofthemeanofthisgroupeddata.Havingnocompasshegothisbearingsfromthesun.轴承的载荷越大,其以转数为单位的寿命就越短动量作用线伸展得越远,角动量就越大截面越大,强度越大Nd第3节翻译练习16Fabricateashieldfrom12cmaluminumalloytothedimensionsshownonFigure
11.Theelectronicdeviceismadefromsemiconductor.Deadtimeisthetimeaworkerlossesfromlackofmaterialsorequipmentbreakdown.Asimilarerrorarisesfromneglectofmultiplecauses.按图11所示,用12厘米厚的铝合金制造防护罩这只电子器件是用半导体做的无效时间是指工人因无原料或设备故障而失去的时间类似的错误可能由于忽视了多种原因而产生Nd第3节翻译练习17Thehardenedwashershallbepreventedfromturningduringlocknuttightening.Washersshallbefromburrsandsharpedges.Thetriggeringcircuitisimmunefromnoise.Themixturearedistinctfromcompounds.Dataisoftendistinguishedfrominformationandfromprograms.当自锁螺母拧紧时应防止淬火垫圈转动这个触发电路不受杂音影响混合物不同于化合物垫圈不应带有毛刺和尖角数据通常有别于信息和程序Nd第3节翻译练习18Highlypoisonousinsecticidesshouldbekeptfromordinaryinsecticides.Electrolysisistheliberationoffreeelementsfromaliquidbypassinganelectriccurrentthroughit.Placethesepartsinaplasticbagandkeepseparatefromotherbearingassemblies.剧毒农药和普通农药要严格分开置放电解就是让电流通过液体,从而使游离元素从液体中分离出来的过程将这些零件装进塑料袋中,和其他轴承部件分开置放Nd第3节翻译练习19CanadianscientistslookedforozonethinningintheArctic.InCanadagovernmentsarealsostartingprogramstorecycleandrecoverCFCs.Theusesofindustrialgasesinourhigh-techworldarenumerousandvaried.加拿大科学家在北极区寻找臭氧层变薄的迹象在加拿大,政府正在开展工作回收和循环使用氟里昂在我们这个技术高度发达的社会中工业气体的用途是多种多样的NdThehummingbirdhasthehighestmetabolicrateperunitofbodyweightintheavianworld.Althoughinrecentyearstheliquidstatehasbeenthesubjectofintensestudytheseveralbookstreatmainlythephysicsofthisstate.Inthe1970sthefocusofdesigninghardwarewasthecreationofcircuitry.在鸟类世界中,单位体重的新陈代谢以蜂鸟为最高虽然近年来液态已成为努力研究的课题,但是这些书主要是谈论液态的物理特征在20世纪70年代,硬件设计的焦点是生成电路第3节翻译练习20Thedecisiontorepairisnoteasyespeciallyinborderlinecases.Allmoleculesareinconstantmotion.Inthestudyoflubricationandjournalbearingsadditionalfundamentalknowledgemustbeutilized.Inordertopreventanydamageorinjurytohumaneyesintrainingalaserenergyattenuatormaybemountedonthelaserexitwindow.做出返修的决定不是容易的,在可修可不修的情况下尤其如此在研究润滑和滑动轴承时,尚需用到另外的基础知识在训练时,为防止误伤人眼,可在激光输出窗口上装上激光能量衰减器一切分子都处在永恒的运动状态之中Nd第3节翻译练习21Theelectricpowerwhichisconsumedinanelectriccircuitismeasuredinwattsorkilowatts.Energyandworkarebothmeasuredinjoules.Powerbeingtheamountofworkdonepersecondismeasuredinwattsjoules/sec.电路中消耗的电力是以瓦或千瓦计量的能和功都用焦耳计量功率是每秒钟所做的功,所以用瓦特(焦耳/秒)计量Nd第3节翻译练习22Objectssinkdownintofluidsuntiltheupthrustequalstheweightoftheobject.Ifapermanentmagnetsisplungedintothecoilthemeterregistersamomentarycurrent.Itisonlyrecentlythatastronomershavebegunspecificresearchintoblackholes.物体沉入流体,直到向上的推力与物体的重量相等如果把永久磁铁插入线圈,电表会记录到一次瞬间电流只是在最近,天文学家才开始对黑洞进行具体的研究NdPhysicsgivesuspowertoadventureintotheunknown.Heattransformsiceintowaterandwaterintosteam.Theprocessconvertsironandsteelscrapsintometalpowder.物理学给予我们探索未知世界的能力热使冰变成水,使水变成蒸汽此法可把钢铁切屑变成金属粉末第3节翻译练习23Considerableliteraturehasgrownuprelatingtoexperimentalconfirmationofelastohydrodynamictheory.Thesuccessfullaunchingofspacerocketshasaddedmuchtoman’sknowledgeoftheupperstrataoftheatmosphere.Theprocessorisinover-allcontrolofthesystem.关于弹性流体动力润滑理论的实验证明,已涌现出大量文献宇宙火箭发射的成功大大增加了人类对大气上层的知识处理器对系统实施全面控制Nd第3节翻译练习24Thesecompoundsareofthesamefamilyoforganicmaterials.Allthetypesofmemorywehavediscussedareof“randomaccess”.Itmightbethoughtthatthesetwoeffectswouldbeofthesameorderofmagnitude.TodayofthefouronlyEarthisknowntobetectonicallyactive.这些化合物属于同族有机物上述的各类储存期都属于“随机存取”类型人们可能会以为这两个效力的大小属于同一个数量级今天,在这四颗行星中,据人们所知只有地球的地壳构造仍在活动NdOfallformsofenergyelectricityisthemostimportant.在所有形式的能量中,电能是最重要的第3节翻译练习25AmagneticsystemismadeofwroughtironarrangedasinFig.8-
16.Flatbeltsareusuallymadeofeitheroak-tannedleatherorafabricsuchascottonorrayonwhichhasbeenimpregnatedwithrubber.Themotorconsistsoftwopartsthestatorandtherotor.磁系统是由熟铁制成,如图8-16所示平型带通常用橡树皮鞣革或浸渍过橡胶的棉织品或人造纤维织品制成电动机由定子和转子两部分构成NdEachstagerequiresadifferentsetoftoolsandsometimesrequiresdifferentequipmentandskills.每一步都要求有一套不同的工具,有时还要求有不同的设备和技术第3节翻译练习26Thischartmaybeplottedonsemilogpaperoronlog-logpaper.Applyasmallamountoftheadhesiveliquidonthefaceofthegasket.FinalcompositionoftheTheaterListisnormallydecidedbythesurgeononthedaypriortooperation.Onfreezingwaterdoesnotcontractbutinsteaditexpands.此曲线图可绘于半对数图纸或对数图纸上在密封垫表面上涂少许粘着剂接受手术人员的最后名单一般由外科大夫在手术前一天做出决定水结冰时,并不收缩,而是膨胀Nd第3节翻译练习27Furtherresearchonthissubjectmaysuggestwaysinwhichearthquakescanbepredictedandprevented.Agoodexampleofthelocaleffectsofpollutiononweatheristheincreaseinrainfallfoundinregionsadjacenttoalargepapermill.Thedesignofstructuresanddrainagesystemsarenotbasedontheseadversesiteconditions.在这方面作进一步研究也许能提供预报和预防地震的方法污染对天气有局部影响,一个很好的实例就是在大型造纸厂附近地区降雨量有所增加工厂的建筑物和排水系统没有根据这些不利的厂址条件进行设计Relationshipsbetweenvoltagesandcurrentsinacircuithavebeenestablishedontheexperiments.OnBohratomictheoryandwaveamplificationtheorylaserhasbeendevelopedbyscientists.电路中电压与电流的关系已根据实验确定根据玻尔的原子理论以及波的放大理论,科学家们研制了激光第3节翻译练习28Itreliesheavilyondigitalprocessing.Ontheseobservationsahypothesismaybeformulated.Themotorisontheoperation.HedevelopedpneumoniacausedbybloodclotsinthelungsaftertravelingtoAsiaonaneconomy-classticket.这在很大程度上要依靠数字处理电动机在运行他在一次乘经济舱飞往亚洲之后,由于肺里产生血块而得了肺炎通过这些观察,可以作出一个假设Nd第3节翻译练习29Theprereducedorrawfineoreisinjectedintothesmeltingreductionfurnacethroughtheuppertuyeres.Gasesreadilydiffusethroughporoussolids.Theradiationcouldpenetratethroughlayersofdifferentmaterials.经过预还原的矿粉或者原始的矿粉都是通过上部的风口送入熔融还原炉的气体很容易通过多孔固体渗出该辐射可以穿透多层不同的材料Throughthecombustionofthefuelchemicalenergyisconvertedintoheatenergy.Therangeandvarietyofworkthatcanbedoneonalathearegreatlyincreasedthroughtheuseofvariouswork-holdingattachments.Atomicenergyhasarrivedintimetosavecivilizationfromdyingthroughlackofpower.Siliconchieflythroughitsbettertemperaturecharacteristicsquicklyreplacedgermaniuminthepowerdiode.通过使用各种工件夹具,可大大扩大车床所进行的作业范围和种类由于硅有较好的温度特性,在功率二极管中,硅很快取代了锗通过燃料的燃烧,化学能转变为热能原子能已及时出现,从而拯救文明使其免于因能源短缺而灭亡第3节翻译练习30Magmasintransittothesurfacewillfurthersupplementthisheat.Themakeupwaterpipelineconveysthemakeupwaterfromthemakeupwaterintakestructuretothecoolingtowerbasin.Afreshcuttercanbeloadedtothespindleinasimilarmanner.向地表移动的岩浆进一步补偿这种热量补给水管道把补给水从取水建筑物输送到冷却塔水池用同样的方法可将新刀具装在主轴上Thefunctionofthecomputerisnotlimitedtoprovidingsupportinsolvingmathematicalproblems.Thesystemisrestrictedtoexaminingthesurfaceonly.Neededisamethodoftimingaccuratetomillionthsofasecond.Cultivationcanbemechanizedtothelargestdegree.该系统仅限于检验金属表面耕作可在最大程度上实行机械化计算机的作用不能只限于帮助解决数学问题上需要有一种精确度达到几百万分之一秒的计时方法第3节翻译练习31Computershaveasyetcontributedlittletopuremathematicaltheory.Airpressureisinverselyproportionaltoaltitude.ThusFig.5issimilartoFig.4binsofarasthesamerecombinationandfiltershavebeenappliedtoboth.Anelectricmotorissimilartoageneratorinconstruction.迄今为止,计算机对纯数学理论的贡献不大气压与高度成反比电动机和发电机在结构上类似第3节翻译练习32Waterentersthecylinderandfillsthespaceunderthepiston.Whenavehiclepassesoveraroaditsweightistransmittedthroughthewheelontothepavementunderit.Buthowcanbouncingsoundwaveshelpoceanographerstoseetheseafloorandthemudsoilandrocksunderit水进入泵筒,并注满活塞下面的空间当一辆车驶过马路时,其重量通过车轮传至车下的路面上而反射波怎样帮助海洋学家去考察海底以及下面的泥、土和岩石呢?Undercertainconditionsheatenergymaybechangedintomechanicalenergyandmechanicalenergymaybechangedintoheatenergy.Thereisnomaterialbutwilldeformmoreorlessundertheactionofforces.Watervaporintheairbreaksdownundertheintenseheat.在力的作用下,一切材料无不变形在一定条件下,热能可以转换成机械能,机械能也可以转换成热能空气中的水蒸气在高温下发生分解第3节翻译练习33Undersometradetermsthebuyermightundertaketoclearthegoodsforexportintheseller’scountry.ThebooksarecategorizedundertheDeweyDecimalSystem.Theagreementforthetradeandcooperationisstillunderadraft.LianyungangNuclearPowerStationisstillunderconstruction.根据某些贸易条款规定,买方须负责在卖方所在国的出口清关这些图书是按照杜威十进制编目的贸易合作的协定仍在草拟中连云港核电站仍在建设中第3节翻译练习34Ithasnoconnectionwiththeautomaticpositioningfacilities.Oxygenisagasthatcanunitewithmanysubstances.Theresistanceusuallyvarieswithtemperature.它与自动定位装置没有关系氧是一种能与许多物质化合的气体电阻常常随温度变化Withtheinventionofthetransistorelectronicsenteredanewphase.Withtheadvanceofscienceandtechnologysomescientificproblemsbecomelesscomplicatedthantheywerethought.随着晶体管的发明,电子技术进入了一个新的阶段随着科技进步,有些科学问题没有原先认为的那么复杂了第3节翻译练习35Themachiningcenterisprovidedwithanautomatictoolchanger.Bricksarealsoproducedinmanydifferentcolorsandwithvariousfinishes.Mostofthemachiningwedoinamachineshopisdonewithcuttingtools.Unixmarketershavelookedwithsomeenvyattheseapplications.加工中心备有自动换刀装置砖也可以烧成不同的颜色,具有不同的光洁度我们在机械加工车间所做的大部分机加工是用刀具来进行的“UNIX”的销售者以很大的热情关注着这些应用程序第3节翻译练习36Withtheadventofmodernmethodsofcommunicationthewholeworldhasbeentransformedintoasinglemechanism.Themachinesmaygetheatedwithoverload.Computersperformparticularoperationswiththeinformationtheyaregiven.由于近代通信方法的出现,整个世界已转变为一个统一的机体机器可因过载而发热计算机根据所收到的信息进行特定的运算Assemblebearinginnerandouterraceswithserialnumbersindexed.Aninterruptisallowedtooccurinaccordancewithspecifiedpriorities.根据特定的优先权允许发生中断根据序号组装轴承内外座圈第3节翻译练习37Withitsmanyadvantageswoodisnotwithoutitsdrawbacksasafuel.Withitscomplexstructureitisliabletoinstall.Withnodiscoverymanylawsofnatureactuallyexistinnature.Withslightrepairtheoldtypeofenginecanbeused.尽管木材有许多优点,但作为燃料仍有缺陷虽然结构复杂,但容易安装许多自然规律虽然尚未被发现,但它们确实存在于自然界之中只要稍加修理,这台老式发动机就可使用第3节翻译练习38Petrolisamixtureofthelower-boilinghydrocarbonswithboilingtemperaturesrangingfrom100°Cto400°C.Neveroperatetheenginewiththewatertemperatureintheradiatorexceeding100°C.Thefield-effecttransistorconsistsofasinglecrystalofdopedsemiconductormaterialintheshapeofabarwithleadsconnectedtobothends.在散热器中的水温超过100°C的情况下决不要开发动机场效应晶体管是一个棒状的掺杂半导体材料的单晶,两端连有引出线汽油是低沸点的碳氢化合物混合体,其沸点范围在100°Cto400°C之间Withthecauseofthefaultremovedatoncethegeneratorkeptworking.Onekindofswitchisinsideametalboxcalledaswitchboxwithahandleontheoutside.Thepressureofagasvariesinverselyasitsvolumewithtemperatureconstant.Withtheswitchopenthereisnocurrentflowingintheload.有一种开关是放在一个称作开关箱的金属箱内,而柄留在外面由于即使排除了故障,发电机继续工作温度不变时,气体压强和体积成反比打开开关,没有电流通过负载第3节翻译练习39Magneticinductioncantakeplacewithoutcontactbetweenthemagnetandtheiron.Withoutdusttherewouldbenocloudsandnorain.Thinplatesarejoinedbymeltingtheiredgestogetherwithouttheadditionoffillingmetal.磁铁和铁块相互不接触便可发生磁感应若没有灰尘,就不会形成云和雨薄钢板是靠熔化其边缘而焊接在一起的,不需要填料金属Abodycannotbemovedwithouthavingaforceactuponit.Hefinishedthestressexperimentwithoutdifficulty.他轻松地完成了这个应力实验若没有力作用于物体上,物体就不能移动第6章总复习题Theconductivityofpolyacetylenedropsrapidlyincontactwithair.Thereisabrighterfutureforintelligentdevicesinthehome.Thescientistsfoundthatthebloodvesselsinthelegcannotswell.Onceuponatimeboldclaimsweremadeaboutcomputersthefutureandthe“paperlessoffice”.聚乙炔一接触空气,其导电性就迅速下降家庭智能装置仍有着更加光明的前景(省译)科学家们发现腿内的血管不会肿胀曾几何时,有人就有关计算机、未来和“无纸化办公”做过大胆的预测Thedoctoradvisedagainsttheuseofthenewtreatment.Ifagoodbasecannotbefoundatareasonabledepththenaso-calleddeepfoundationmustbeprovided.Magneticlinesofforcecannotbeseenbutweknowtheyexistbywhattheydo.磁力线是看不见的,但是我们按照它们的作用即知它们的存在医生建议不要使用新的治疗方法若在合理的深度内找不到坚实的地基层,那就要采用所谓的深基础WemayprocessdirectlywithKirchoff’svoltagelawforthecircuit.Thepropervaluesofaandbaredeterminedfromtwoconditions.Optionalcommunicationsarefreefromelectromagneticinterference.Thistypeofdiscrepancycouldhaveresultedfromdifferencesinkinetics.a和b的值由两个条件决定对于电路,我们可直接从克希荷夫电压定律讲起光电通信不受电磁的干扰这种差异可能是由动力的不同而造成的Thevisualimageofthelettersmakingupthewordisconvertedintoitsspokenequivalent.Primitivemanmadeweaponstoolsandutensilsofcopperbrassandbronze.Thelongerwavelengthsofradiosignalspassthroughtheatmosphererelativelyundisturbed.将组成词的各字母的视觉形象转换成该词对应的发音相对来说,波长较长的射电讯号通过大气时没有受到干扰原始人类用铜、黄铜和青铜制作成各种武器、工具和器皿Mosthardness-testingsystemsemployastandardloadwhichisappliedtoaballorpyramidincontactwiththematerialtobetested.Allmetalsarecorrodibleunderthepropercircumstances.Thedesignoftherocketnozzlealsohasmuchtodowiththebehavioroftheexhaustandtheresultingvelocityofthevehicleitself.多数的硬度实验系统使用一标准载荷加在与实验金属相接触的小球或棱锥上所有金属在一定情况下都是可腐蚀的火箭喷管的设计与排气的性能及飞行器本身的有效速度有很大关系Peripheralmillingoperationsareusuallyperformedonmillingmachineswiththespindlepositionedhorizontally;howevertheycanalsobeperformedwithendmillsonvertical-spindlemachines.Copperandaluminumarethebestconductorsofelectriccurrentonlyaftersilver.Fromvariousexperimentswecannotbutthinkthetheorystillholdsgood.周铣作业通常在带有水平定位主轴的铣床上进行,但也可以在带有端面铣刀的主轴铣床上进行铜和铝是仅次于银的最好的导电体根据各种实验,我们不得不承认这个理论依然是行之有效的Hydrogenisgeneratedfromzincandsulfuricacid.Thesortoffishcannotliveinthetemperatezoneletaloneinthefrigidzone.Thelocomotivedevelopedsomenewproblemsonitsline-test.Gasescanbechemisorbedorphysicallyabsorbedonsolids.氢由锌和硫酸所产生这种鱼不适合在温带生活,更不必说在寒带了这台机车在试运行时出现了一些新问题气体能化学吸附或物理吸附在固体上Underidealconditionsthefatiguefailurewillconsistofaspottingoftheload-carryingsurfaces.Oxidationimpliesthecombinationofotherelementswithoxygentoformcompounds.在理想条件下,疲劳失效将是承载表面的点蚀氧化意味着其他元素与氧形成化合物
7.1连词的一般译法第1节翻译练习1Carbonsteelcontainsonlyironandcarbonwhilealloysteelcontainssomeotheralloyingmetals.Becausethiscurrentcontinuallyreversesindirectionitiscalledanalternatingcurrent.Liquidandvaporphasescannotcoexistinequilibrium.碳钢只含有铁和碳,而合金钢含有一些别的合金金属由于这种电流不断地改变方向,故称为交流电液相和气相不能在平衡中并存第1节翻译练习2Somecompaniesreplacecertainpartsregularlydeterminingtheeffectivelifeofapartandthenreplacingitjustbeforeitwouldwearout.Thecostofmakingthesetestsisverylowwhenitisdividedbythetotalnumberofpartsmanufactured.一些公司定期更换某些零部件,先推定零部件的有效寿命,以便在零部件即将磨损之前予以更换如果以生产零件的总数来划分,这些实验的成本会非常低WhyusemetalwhenyoucanuseplasticAbriefdescriptionofhowtransistorsaremanufacturedisgivenhere.Thatiswhysurfactantsaresowidelyusedinindustry.既然能用塑料为什么你却使用金属呢?这里对晶体管的是生产方法作一简略叙述这就是在工业上广泛使用表面活性剂的原因第1节翻译练习3Sometimesitisnecessarytodrilltoadepthof1000metersormorebeforewaterisfoundinsufficientquantity.Itisstatedthatthepositioningsystemhasanaccuracyofrepeatabilitywithin
0.0002inch.Whenshortwavesaresentoutandmeetanobstacletheyarereflected.有时必须钻到1000米或更深的深度,才能找到足够量的水据称,该定位系统的重复精度在
0.0002英寸短波发送出去,遇到障碍就反射回来
7.2常用并列连词的译法第2节翻译练习1Computerscopewithnegativenumbersandfractionsinbinaryarithmetic.Oxygenischemicallyactiveandtakespartinmanyreactions.计算机采用二进制算法来处理负数与小数氧的化学性能活泼,能参与许多反应(省译)ModernelectroniccomputersandotherdeviceswillbemadesmallerbythedevelopmentofLSI.Someelectricalengineersdesignandmaintainpowerplantstransmissionlinesandhomeandfactoryelectricalinstallations.大规模的集成电路的发展将使现代化电子计算机以及其他装置越来越小有些电气工程师设计和保养发电厂、输电线、以及各种家用和工业用电器设备第2节翻译练习2Theinducedelectromotiveforcelagsandthecurrentleads.Likechargesrepelandunlikechargesattract.感应电动势滞后,而电流导前同性电荷相斥,异性电荷相吸(省译)Transformersarecommonlyusedinradioreceiversandelectricalcommunicationcircuitsandtheyaregenerallymuchsmallerthanthoseforpowertransmission.Analyzingthedynamicsofthewayapersonsignshisorhernameandnotjusthowthesignaturelooksisonebasisofabiometricverifier.变压器通常用于无线电收音机和电信电路中,可是这些变压器一般比用于输电的变压器小得多分析一个人签名时书法的笔力,而不只是分析签名的字形如何,这是生物统计学核实器的一个基本点第2节翻译练习3Itisimportanttoknowthatdifferenttypesofcontrolcircuitsmaybeusedinonecontrolsystemandacompletedcontrolloopmayconsistofacombinationofelectricpneumaticorhydraulicelements.重要的是要知道,在一个控制系统中可使用不同类型的控制电路,而且一个完整的控制回路可由电力、气动或液压配合组成Thesynchronousmotorisevenmoreexpensiveandrequiresasourceofd.c.excitationaswellasspecialsynchronizingcontroltoapplythed.c.poweratthecorrectinstant.Telephonecommunicationisnowwidespreadandefficient.Themachineisoldandheavy.同步电动机则更贵,而且需要直接励磁电源和专门的同步控制器以便在适当的瞬间接入直流电源现在的电话通讯既广泛又有效这台机器又旧又笨重第2节翻译练习4Wehavetoreplacesomeofitspartsandmakethismachinemoreefficient.Tomaketheballoondescendthe“pilot”openedavalveandallowedsomeofthegasescape.我们必须调换某些零件,以使这台机器效率更高为使气球降落,“飞行员”打开阀门,以使部分气体逸出Changeoneormorestepsandwewillimprovethequalityofthefinishedproducts.Useatransformerandwecantransformpoweratlowvoltageintopowerathighvoltageandviceversa.若改变一个或几个步骤,我们就有可能提高成品的质量用了变压器,我们就可以把低电压变为高电压,也可把高电压变为低电压第2节翻译练习5Uncapopeningsinindicatorsandconnectlines.Installaluminumwashersnesttopumpsteelwashersnextandinstallnuts.Leadlackstensilestrengthanditcannotbedrawnoutintheformoffinewire.取下仪表开口处的盖子,再接上管路铅的张力差,因此不能制成细丝状紧贴泵处安上铝垫片,然后加钢垫片,再安上螺栓ForLPturbinethereisnoresidualaxialthrustcausedfrombladingbecauseoftheturbine’sdouble-flowarrangementofbladingandthusnobalancingpistonisneeded.至于低压汽轮机,并没有残存的轴力,因为汽轮机的叶栅作双流配置,因而也无需采用平衡轮第2节翻译练习6Theplanisverycomplicatedtechnicallybutthegeneralideaisquitesimple.Nowtheelectronswhichhavebeendrivenontothenegativeplatearetryingtogetbacktothepositiveplatebutcannotdosobecauseofthee.m.fwhichisappliedtotheplates.这一计划在技术上十分复杂,但总的想法却相当简单现在已被赶到负极上的电子力图返回正极,可是由于极板上施加有电动势的缘故而办不到Therearealreadyanumberofmodernvehicleswhicharenotyetincommonusebutwhichmaybecomeausualmeansoftransportinthefuture.现在已有一些现代化的运载工具,它们目前尚未被普遍使用,但将来可能成为一种日常的交通工具第2节翻译练习7ButthathepreventedmeImighthavekeptthemachinepartsinthedampplace.Butthatthecheckingupoftheexperimentaldatahadtakensomuchtimeweshouldhavecompletedourworklongago.若不是他阻止,我可能就会把那些机器零件保存在潮湿的地方假若检验这些实验数据不花那么多时间,我们早就完成了这项工作Butforairtheearthwouldundergoextremechangesintemperature.Butforthelawsofmotionasabasisthousandsofdiscoveriesandinventionswouldhavebeenoutofthequestion.要是没有空气,地球温度就会发生剧变如果没有运动定律作为基础,就不可能有成千上万的发现和发明第2节翻译练习8Thepositiveandnegativeionsbecomeseparatedordissociated.Noelectricchargeshavebeenobservedofsmallermagnitudethanthechargeofprotonsorelectrons.Foodsquick-frozeninliquidnitrogenorcarbondioxidehavetransformedthewayweeat.正负离子彼此分解或电离还没有观察到比质子或电子的电量更小的电荷用液态氮或二氧化碳速冻的食物已改变了我们的饮食习惯Wewillstartwithacubicinchofhydrogenatatmospherepressureortheairpressureattheearth’ssurface.Scientistshaveshownthatcertainchemicalsareslowlyerodingtheozonelayer.ThemainculpritsarechlorofluorocarbonsorCFCs.Fireisachemicalactionoranactiontakingplacebetweendifferentchemicalsubstances.我们从大气压力(即地球表面的空气压力)下的一立方英寸氢气开始科学家们已经证明,某些化工产品会慢慢破坏臭氧层主要诱因就是氯氟甲烷,即氟里昂火是一种化学反应,也就是发生在不同化学物质间的一种作用第2节翻译练习9Rightorwronghistheoryisthemostinfluential.Allmethodssimpleorcomplicatedareemployedinthetension-test.Youhavetoopentheswitchrightawayorelsethefusewillbeburnedoff.无论对错,他的理论无疑是最有影响力的在拉伸试验中,所有方法不论简单还是复杂,都用过了你必须把开关立即断开,否则保险丝就会烧断Abodymustmoveornoworkisdone.Theseoldtransformershavebeenusedfortenortwentyyears.Thenewly-installedgeneratingsetwillbeputinoperationamonthorso.物体必须移动,否则就没有做功这些旧变压器已经使用大约一二十年了新机组再有一个月左右就投入运行第2节翻译练习10Thecentralcomputer’sjobistorunthroughthemapsinitsdatabaseaswellasdetailsonroadworksweatheretc.Boilingpointelevationsaswellasthevariationoftheheatcapacitiesandlatentheatswithtemperaturearenegligible.中心计算机的任务是查阅储存在数据库中的地图以及修路工程、天气等详细情况沸点升高以及热容和潜热随温度的变化而忽略不计Hediscoveredthathecouldsendthesoundofmusicaswellasthedot-and-dashsoundsofMorseCodethroughthecoil.Thephysicsstudentsstudychemistryaswellasphysics.他发现不仅能使线圈传送莫尔斯电码的点划音,而且也能是线圈传送音乐(倒译法)物理系学生不仅学物理,而且要学化学(倒译)Experimentaldatacanbeusedtoillustratetheapplicationtechniquesaswellastodemonstratethevalidityoftheapproach.Inordertogetvariousvitaminsapersonshouldeatadietincludingvegetablesaswellasmeat.实验数据既能用来说明应用技术,也能用来验证方法的有效性(顺译)为了摄取多种维生素,一个人既应该吃些素食,也该吃荤食(顺译)第2节翻译练习11Whenlightstrikesanopaqueobjectthelightiseitherabsorbedorreflected.Theoxygencontainedintherocketiseitherintheliquidorinthesolidform.Whenastronomerslookattheskytheyexpecttoseeeitherastaroragalaxy.当光照在不透明的物体上时,光或是被吸引或是被反射火箭内储存的氧或是液态的,或是固态的每次天文学家观测天空,他们期望看到的不外乎是一个恒星或一个星系第2节翻译练习12Therearematerialswhichareneithergoodconductorsnorgoodinsulators.Itisneitherpossiblenorpracticaltomakemanypartstoanexactsize.Neitherglassnorporcelainisaconductor.有些材料既非良好的导体也非良好的绝缘体要使许多零件加工尺寸丝毫不差,既不可能,也不切实际玻璃和陶瓷都不是导体第2节翻译练习13Notonlydoesairexertpressurebutitalsohasbuoyancy.Thismethodnotonlysimplifiesanalysisbutalsofacilitatesmeasurements.空气不仅产生压力,而且有浮力这种方法不仅简化了分析,而且也便于测量
7.3常用主从连接词的译法第3节翻译练习1Thelooposcillatorfrequencycanbethesameasoramultipleofthereferencefrequency.Becausead.c.motoristhesamephysicalmachineasad.c.generatoritsequivalentcircuitisexactlythesameasthatofageneratorexceptforthedirectionofcurrentflow.环路振荡器可以和参考频率相同,也可以是参考频率的倍数由于直流电机与直流发电机的物理结构是一样的,其等效电路除了电流方向外也与直流发电机相同R2asisshowninFig.3hasbeensplitinhalvestoenablethefeedbacktobeapplied.Undercertainconditionsabodycanbechargedashasbeensaidbefore.如图3所示,R2被分为两半,使得反馈能够加上去在一定的条件下,物体能够带电,这在前面已经讲到第3节翻译练习2AscurrentisincreasedthefluxbuildsupaccordingtoCurve
2.Asyouaredoingtheexperimentwritedowntheobservations.当电流增大,磁通沿着曲线2增大在你做实验的同时,把观察到的情况记录下来Asthe21stcenturyapproachescomplicateddigitaltechnologiesandthepromiseofexplodingbandwidtharecombiningtocreateathirdkindofconvergence.Asparticlehasnoextentitspositionisapoint.Aswaterisacompounditcanbedecomposed.Asthecurrentwastrebledabruptlythesecondvalveburntout.随着21世纪的来临,复杂的数字技术与带宽不断扩大的前景相结合将会创造出第三种意义的“连通”由于质点没有广度,它的位置是一个点因为水是化合物,所以可以分解由于电流突然增加了两倍,第二个电子管烧坏了第3节翻译练习3Gravitytheforceoftheearth’sattractiongovernstheatmospherejustasitgovernssolidobjects.Somewavesarereflectedasamirrorreflectslight.Thelargeforceistothesmallforceasthelargeareaistothesmallarea.引力,即地球的吸引力,正像它影响着固体那样影响着大气大的力与小的力之比就像大面积与小面积之比有些波被反射,就像镜子反射光一样Electrontubesarenotsolightinweightassemiconductordevices.Thetoolsaremachinedtotolerancesascloseas
0.0001inch.Moderncomputerscanstorethefactsasfastastheyaregatheredandpourthemoutwhenevertheyareneeded.电子管的重量不如半导体器件那么轻现代计算机能尽快地将收集到的资料储存起来,并在需要时输送出去工具加工的误差接近
0.0001英寸第3节翻译练习4Complicatedasmodernmachineisitisessentiallyacombinationofsimplemachines.ThevariouslossesinamachinegreatastheyaredonotinanywaycontradicttheLawofConservativeofEnergy.Verylargeasthenuclearenergysupplyintheinteriorofthestarisitisneverthelessfinite.现代化机器虽然复杂,但实质上不过是许多简单机械的组合虽然恒星内部的核能储量很大,但仍是有限的机器中的各种损耗尽管很大,但这与能量守恒定律丝毫也不矛盾第3节翻译练习5Eachofthetwowirescarryingcurrentshasamagneticfieldasifitwereamagnet.Wateralsopressesontheinsideofthecontainerasthoughitistryingtoescape.通电的两根导线每一根都有一个磁场,好像是一块磁铁水对容器的内壁也产生压力,似乎水力图要流出来一样第3节翻译练习6Solongaswehavemeansofproducingheatcanwekeepasteamengineworking.Itiscapableofkeepingitsshapeaslongastheplanetkeepsspinning.只要设法产生热,就能使蒸汽机做功只要恒星连续不断地旋转,它就能保持自己的形状AsfarasprocessingpowerisconcernedthedifferencebetweenaPCandamainframeisclosingfast.Asfarasthequalityoftransformersisconcernedtheonestheyproducedarebetter.就处理能力而言,PC机和大型机之间的差异正在迅速缩小就变压器的质量而言,他们生产的变压器更好第3节翻译练习7Assoonasprintingqualitylevelscanbemaintainedandtheeffectivelifeofthemachineincreasedapreventivemaintenanceprogramiseffective.Assoonastheelectronsaretransformedandionsformedtheyarecharged.Theelectronscreateamagneticfieldassoonastheybegintomove.一旦印刷质量得以保证并且机器有效使用期得以延长,经常性维修保养计划才是行之有效的一旦电子转移,形成离子,它们就带电了电子一开始运动,就产生磁场第3节翻译练习8Beforeyoujoinoneelectricwirewithanothermakesurethecurrenthasbeenswitchedoff.Theleavesseparatebeforethemetallicboardistouched.Furtherstudyisneededbeforetheoriginofthecovalentbondcanbeconsideredasettlequestion.在你把一根电线和另一根电线连接起来之前,务必先切断电源在接触金属板以前簧片分开需进一步深入研究,才能解决共价键的起源问题Thedirectionofthecurrentwasdecidedbeforeelectronswerediscovered.Sheswitchedontheenginebeforewecouldstopher.电流方向确定了,电子才被发现我们还没来得及阻止她,她就开动了发动机第3节翻译练习9Evenifoneoftheenginesfailstheplanewillbeabletocontinueitsflightsafely.Ithasundergoneachemicalchangesinceevenifcooleditwillnotreturntoitsoriginalcondition.Thelathecanturnholesevenifitisnotadriller.即使发动机中有一台失灵,飞机仍能安全地继续飞行车床尽管不是钻床,也能钻孔从那时起它已发生化学变化,即使加以冷却,它也不会恢复原样第3节翻译练习10Ifa.c.powerisavailablealldrivesrequiringconstantspeedshouldusesquirrel-cageinductionorsynchronousmotorsbecauseoftheirruggednessandlowercost.Ifthepartingcontactsaremadeoflow-melting-pointmaterialsuchasbrassorcopperthearcwillgooutatthefirstcurrentzeroasthevoltageisinsufficienttoreestablishascathodespotaftercurrentreversal.因为鼠笼式感应电动机或同步电动机经久耐用且成本低,若有交流电源可用,所有需要恒速驱动的装置应使用这两种电机如果分段的触点采用低熔点金属(如黄铜、铜)等制作,则电弧会在第一个电流过零点熄灭,因为在电流极性变化后,没有足够的电压再次产生阴极辉光放电Peoplemighthaveavoidedmanyaccidentsifultrasonicmethodshadbeenknown.Ifad.c.systemweretobeusedthetransmissionlosswouldbeverygreat.Iftherewerenoairtheearthwouldundergoextremechangesintemperature.Thequestionisifthereareotherchiefsourcesoforganicmaterialsinadditiontocoalandpetroleum.要是过去知道超声波法,人们当时是可以避免许多事故的如果没有空气,地球温度就会发生剧变若采用直流电力网,输电损失就会很大问题是除了煤和石油之外是否还有别的有机物主要来源第3节翻译练习11Thecurrentflowsthroughaconductorincasethereisadifferenceofpotentialbetweentheendsoftheconductor.Ordinarymovementswouldbeimpossibleincasefrictionwereunavailable.如果导体两端有不同电位时,电流就可以通过导体流动假如没有摩擦力,常见的活动都不可能进行第3节翻译练习12Onceformedthedepletionregionactsagainstfurtherdiffusion.Oncethemeltingpointisreachedthetemperaturewillnotincreaseanyfurtheruntilthemeltingiscompleted.Onceanobjectisinmotionitwillcontinuetomove.耗尽区一旦形成,便会阻碍进一步扩散一旦达到熔点,温度就不再升高,直到完全熔化物体一旦处于运动状态,就会继续运动下去第3节翻译练习13Thepressureofagasisinverselyproportionaltoitsvolumeprovideditstemperatureiskeptconstant.Theblast-furnaceisexpectedtoremaintheworld’schiefsourceofironunitssteelmakingprovidedadequatesuppliesofsuitablecokingcoalremainavailableatcompetitivecost.如果温度保持不变,则气体压力和其体积成反比只要有足够的焦煤且成本低,高炉仍将是世界上主要的炼铁设备Allsubstanceswillpermitthepassageofsomeelectriccurrentintheeventthatthepotentialdifferenceishighenough.Themagneticeffectdoesnotrepresentacontinuousexpenditureofenergysupposingthatthecurrentissteady.倘若电位差足够高时,所有的物质都将可能通过若干电流假如电流稳定的话,磁效应不再继续消耗能量第3节翻译练习14SincethattimeespeciallysincetheintroductionoftheBessemerprocesstheageofironhasturnedintoanageofsteel.Electricityhasfoundwideapplicationsinceitwasdiscovered.自从那时起,特别是自从采用贝西默炼钢法以来,炼铁时代转变为炼钢时代自从发现电以后,电就获得了广泛的应用Sinceplanetesimalsaggregatedatdifferentdistancesfromthesun’sheatandlightthecompositionoftheplanetsvaries.Sincethesecondarywindingisnormallyoperatedintoahigh-impedancecircuitthesecondarycurrentisquitesmall.由于微星聚集的地点离太阳的热和光远近不同,行星的组成也不同因为次级绕组通常被输入高阻抗的电路,所以次级电流很小第3节翻译练习15Largeaccumulationsofplantremainsindicatethatthedepositswereformedincloseproximitytolandinaswampestuaryordelta.Oneconditionforthisisthatthepolymerconsistsofalternatesingleanddoublebondstermedconjugateddoublebonds.若是植物遗骸大量堆积,这表明沉积物是在紧靠陆地的沼泽、港湾或三角洲中形成的(宾从)一种情况是,这种聚合物由单双键交替构成,即所谓的共轭双键(表从)Weareallfamiliarwiththefactthatnothinginnaturewilleitherstartorstopmovingbyitself.Theporespaceofsoilthatisthoroughlysoakedwithwaterdoesnothaveanyair.Thiscouldresultinthedevelopmentoftinypowerfulcomputersthatrunforextendedperiodsoftimeonlittlepower.我们都熟知这样一个事实自然界没有一个物质会自行开始运动或自行停止运动(同位从)完全被水浸没的土壤,其孔隙没有丝毫空气(定从)这种技术可以用于开发体积微小、功能强大的计算机而这类计算机依靠极少的电能就可以长时间地工作(定从)第3节翻译练习16Manysubstancessuchasglassandwoodconductsopoorlythattheymaybecallednonconductorsorinsulators.Atanestimated80beatspersecondthebeehummer’swingsmovesorapidlythatthenakedeyecannotdetectthem.诸如玻璃、木材之类的物质传导性极差,所以可称为非导体或绝缘体(结果状从)蜂鸟的翅膀估计每秒扇动80次,速度之快使肉眼看不到它的翅膀(结果状从)Cablesareusuallylaidundergroundsothattheirlifemaybeextended.Nowthatwehaveexaminedseveralareasofnaturalscienceperhapsitwouldbewelltoattempttodefinescience.Leadistoxicinthatithampersbraindevelopment.电缆通常安装在地下,为的是延长其寿命(目的状从)既然我们已经仔细研究了自然科学的几个领域,现在不妨给科学下个定义(原因状从)铅有毒,因为铅会影响大脑发育(原因状从)第3节翻译练习17Unlessthesteamissuperheatedhigherpressurewillbenecessary.Acopperwireisnotaffectedunlessthereiselectricalpressure.Usuallysubstancescan’texpandunlesstheyareheated.如果蒸汽不是过热蒸汽,就需要较高的压力铜线不受磁铁的影响,除非它载有电流物质如果不受热,一般是不会膨胀的第3节翻译练习18UntiltheSCRwasdevelopedthethyratronwastheonlycontrolledrectifieravailable.Rubberwasknownonlyasanaturalproductuntilitssynthesiswasachievedin
1916.Notuntilthejetenginehadcomeintousecouldplanestravelatsupersonicspeeds.在研制出可控硅之前,闸流管是唯一可用的可控整流元件在1916年人工合成橡胶之前,人们只知道橡胶是一种天然产品直到喷气发动机投入使用,飞机才能做超音速飞行Whenthewatertemperatureisincreaseditvaporizesmorequicklyuntilitreachesboilingpoint.水温升高时,水蒸发得越来越快,直到达到沸点为止第3节翻译练习19Preciselywhathappenstotheatomicstructureofmetalsatsuchlowtemperaturesisstillnotwhollyunderstood.Sincesoundtravelsdifferentlythroughdifferentmaterialsanalyzingthesoundscanrevealwhatthefloorismadeof.在如此低的温度下金属的原子结构到底发生什么变化,还不完全清楚(主从)因为声音在不同的物质中传播情况不同,分析这些声音能够知道海底是由什么构成的(宾从)Aprogrammermustmakeoutineverydetailtheproblemtobesolvedinwhatiscalledmachinelanguage.Theseillustrationsshowwhathappenstothemixtureafteritentersthecylinderoftheengine.Themethodofphysicsistoanalyzefirstthesimplercasestoextractwhatwecanfromthemandtogoforwardtomoreandmorecomplicatedcases.Whattheimagetubedoesisnothardtodescribe.程序编制人员要用所谓的机器语言把要解决的题目详尽地编排出来(宾从)这些插图显示混合物进入汽缸后会发生什么情况(宾从)显象管的作用不难说清(主从)物理学的方法是首先分析一些较简单的事例,从中吸取我们所能吸取的知识,然后进一步分析越来越复杂的事例(宾从)第3节翻译练习20Wedon’tknowwhenthebesttimesareforseeingMercury.Wedon’tknowwhentheycangivethetransformersweordered.ThiswastheperiodwhenhebegantheresearchwhichresultedinthecreationofhisfamousTheoryofRelativity.我们不知道观察水星的最好时机是什么时候(主从)我们不知道他们什么时候开始交付我们订购的变压器(宾从)就在这期间,他开始进行一项研究,通过这项研究创立了著名的相对论(定从)Inthoseyearswhenelectricityhadnotbeendiscoveredpeopleknewnothingofconductorsandinsulators.在电还没有被发现的年代里,人们不知道有导体和绝缘体(定从)第3节翻译练习21Whenasubstanceisdissolvedinwaterthefreezingpointofthewaterislowered.TheSCRwillonlypasscurrentwhenitsgateispulsed.Newton’sfirsttwolawsholdonlywhentheyareobservedinunacceleratedreferenceframes.当一种物质溶解于水时,水的冰点就会降低只有当可控硅的门电极受脉冲作用时才能让电流通过牛顿的第
一、第二定律,只有在非加速的参照系中作观察时,才能成立Anelectriccurrentexistswhentherearechargesinmotion.如果有电荷运动,就存在着电流第3节翻译练习22Wherethepowerstationwillbebuiltisunderdiscussion.Universalconnectivitywillbringtogetheralltheinformationandservicesyouneedandmakethemavailabletoyouregardlessofwhereyouarewhatyouaredoingorthekindofdeviceyouareusing.电站建在什么地方正在讨论中(主从)通用连接技术将能把你所需要的信息和服务收拢起来而且无论你在哪里,无论你在做什么,无论你使用何种设备,它都能将这些信息和服务送到你手上(宾从)Thenarosethequestionwhereweweretobuythegeneratorsneeded.Waterpowerstationmustbebuiltwheretherearewaterfalls.Wherethewattistoosmallaunitwemayusethekilowatt.这时就产生了这样一个问题,我们到哪儿买所需要的发电机?(同位从)水电站必须建在水有落差的地方(状从)在用瓦作单位太小的情况下,我们可用千瓦(状从)第3节翻译练习23Resistantandtolerantvarietiescanhelpmitigatetuberdamagewherenematodesarepresent.MosturbanareasnowhaveaTDDrelaycenterwhereoperatorsserveasintermediariesbetweenTDDusersandstandard-phoneusers.Surroundingeverymagnetthereisaregionwheremagneticforcesact.在每一块磁铁的周围都有一个磁力作用的区域(定从)抗病虫品种可以有助于减缓线虫对球根的损害(定从)现在大部分城市市区都有“耳聋电信装置”中继中心,在那里接线员是“耳聋电信装置”用户和普通电话用户的中间人(定从)Thereducingtopgascontaining70percentcarbonmonoxideplushydrogenflowsfromanoutletpipelocatednearthetopoftheDRfurnaceintothetop-gasscrubberwhereitiscooledandscrubbedtoremovedustparticles.第3节翻译练习24Thequestioniswhethertheserelaysandbreakerscomeuptothemark.Wewonderwhethersimplerandmoreinclusiveconservationlawsexist.Thereisnodifferencewhetherornotthetemperatureiskeptconstant.Awaterfallwhetheritisman-madeornaturalalsopossessesenergy.我们不知道是否有形式更简单、运用范围更广泛的守恒定律(宾从)温度是否保持不变,这没有什么关系(同位从)问题是这些继电器和断路器是否合乎要求(表从)瀑布,不管它是人造的还是天然的,也具有能量(状从)第3节翻译练习25Whichofthesegeneratorsisthemostefficienthastobetested.Theproblemiswhichgeneratoryourepairfirst.AstowhichoftheseapparatusesisthebestIcan’tgiveyouanydefiniteanswer.这些发电机中哪一个最有效还有待试验(主从)至于这些装置中哪台最好,我不能作任何肯定的回答(宾从)问题是你先修哪一台发电机(表从)第3节翻译练习26Technologytriestofindapplicationsfornewideaswhichsciencediscovers.Inordertokeeptheenginespeedwithinthelimitswhichitwasdesignedforadevicewhichisknownasagovernorisincorporatedintheengine.Thebasicprinciplewhichataperecorderfunctionsonisthatofmagnetism.技术力图为科学所发现的新思想找到应用(定从)为了使发动机的转速保持在所设计的范围之内,在发动机里装有被称为调速器的装置(定从)磁带录音机的基本工作原理就是磁性原理(定从)Moleculesinturnaremadeupofatomswhicharesmallerparticlesstill.AnexperimentalstationhasbeenestablishedofftheIvoryCoastofAfricawhichutilizesthedifferenttemperaturelevelsofseawater.Lighthasahigherfrequencythanradiovavesormicrowaveswhichgivesitagreaterinformationcarryingcapacity.分子本身又是由原子构成,后者是更小的粒子(定从)在非洲象牙海岸沿海已建立起一座试验性发电站,该发电站利用海水的温度级差来发电(定从)光的频率高于无线电波和微波,这就使它具有更大的信息运载能力(定从)Atpresentmicrowavetechnologywhichincludesmicrowaveheatingandmicrowavesurveyisbeingwidelyappliedtoindustrialandagriculturalproduction.Manypeoplecouldfindthatvideoconferencingyieldsproductivitygainswhichmakeitworththeinvestmentoftimeandmoney.目前,微波技术,包括微波加热和微波测量,正广泛地应用于工农业生产(定从)许多人会发现,视频会议系统可以提高生产效率,因此它值得我们投入时间和金钱(定从)第3节翻译练习27Motionisabsolutewhilestagnationisrelative.Newtypesofcomputersaresmallerinsizewhiletheyaresimplerinoperation.Eachfaceisanequilateraltrianglewhilethreefacesmeetateachvertex.新型计算机体积较小,而且操作也比较简单每一个面是一个正三角形,而且在每一个顶点有三个面相交运动是绝对的,而静止是相对的第3节翻译练习28Whileacrystalsolidmeltsthereisnochangeintemperature.WhilethereareheatlossesinasteamturbineIcannotproveit.Whileasparkofliferemainsitisadoctor’sdutytosavethepatient.当晶态固体熔化时,温度没有变化虽然涡轮机内有热损耗,但我无法加以证明只要病人还有一息生机,医生就有责任挽救第3节翻译练习29Itisstillnotclearinmymindwhyageneratorcanproducepower.Thisiswhysomeconjugatedpolymersexhibitelectro-luminescence.Weallknowwhythegroundlosesheattotheair.我仍然弄不明白为什么发电机能发电(主从)这就是为什么一些共轭聚合物具有电致发光的特点(表从)我们都知道为何地表把热量输送给空气(宾从)Thereasonwhyelementsemitradioactiveraysisthattheyareconstantlydecaying.Thereasonwhytheturbinedoesn’tworkisthelackoflubricant.元素射出放射线的原因是因为它们不停地在衰变(定从)那台汽轮机运转不灵的原因是缺少润滑油(定从)第7章总复习题Theconductivityofpolyacetylenedropsrapidlyincontactwithair.Thereisabrighterfutureforintelligentdevicesinthehome.Thescientistsfoundthatthebloodvesselsinthelegcannotswell.Onceuponatimeboldclaimsweremadeaboutcomputersthefutureandthe“paperlessoffice”.聚乙炔一接触空气,其导电性就迅速下降家庭智能装置仍有着更加光明的前景(省译)科学家们发现腿内的血管不会肿胀曾几何时,有人就有关计算机、未来和“无纸化办公”做过大胆的预测Thedoctoradvisedagainsttheuseofthenewtreatment.Ifagoodbasecannotbefoundatareasonabledepththenaso-calleddeepfoundationmustbeprovided.Magneticlinesofforcecannotbeseenbutweknowtheyexistbywhattheydo.磁力线是看不见的,但是我们按照它们的作用即知它们的存在医生建议不要使用新的治疗方法若在合理的深度内找不到坚实的地基层,那就要采用所谓的深基础WemayprocessdirectlywithKirchoff’svoltagelawforthecircuit.Thepropervaluesofaandbaredeterminedfromtwoconditions.Optionalcommunicationsarefreefromelectromagneticinterference.Thistypeofdiscrepancycouldhaveresultedfromdifferencesinkinetics.a和b的值由两个条件决定对于电路,我们可直接从克希荷夫电压定律讲起光电通信不受电磁的干扰这种差异可能是由动力的不同而造成的Thevisualimageofthelettersmakingupthewordisconvertedintoitsspokenequivalent.Primitivemanmadeweaponstoolsandutensilsofcopperbrassandbronze.Thelongerwavelengthsofradiosignalspassthroughtheatmosphererelativelyundisturbed.将组成词的各字母的视觉形象转换成该词对应的发音相对来说,波长较长的射电讯号通过大气时没有受到干扰原始人类用铜、黄铜和青铜制作成各种武器、工具和器皿Mosthardness-testingsystemsemployastandardloadwhichisappliedtoaballorpyramidincontactwiththematerialtobetested.Allmetalsarecorrodibleunderthepropercircumstances.Thedesignoftherocketnozzlealsohasmuchtodowiththebehavioroftheexhaustandtheresultingvelocityofthevehicleitself.多数的硬度实验系统使用一标准载荷加在与实验金属相接触的小球或棱锥上所有金属在一定情况下都是可腐蚀的火箭喷管的设计与排气的性能及飞行器本身的有效速度有很大关系Peripheralmillingoperationsareusuallyperformedonmillingmachineswiththespindlepositionedhorizontally;howevertheycanalsobeperformedwithendmillsonvertical-spindlemachines.Copperandaluminumarethebestconductorsofelectriccurrentonlyaftersilver.Fromvariousexperimentswecannotbutthinkthetheorystillholdsgood.周铣作业通常在带有水平定位主轴的铣床上进行,但也可以在带有端面铣刀的主轴铣床上进行铜和铝是仅次于银的最好的导电体根据各种实验,我们不得不承认这个理论依然是行之有效的Hydrogenisgeneratedfromzincandsulfuricacid.Thesortoffishcannotliveinthetemperatezoneletaloneinthefrigidzone.Thelocomotivedevelopedsomenewproblemsonitsline-test.Gasescanbechemisorbedorphysicallyabsorbedonsolids.氢由锌和硫酸所产生这种鱼不适合在温带生活,更不必说在寒带了这台机车在试运行时出现了一些新问题气体能化学吸附或物理吸附在固体上Underidealconditionsthefatiguefailurewillconsistofaspottingoftheload-carryingsurfaces.Oxidationimpliesthecombinationofotherelementswithoxygentoformcompounds.在理想条件下,疲劳失效将是承载表面的点蚀氧化意味着其他元素与氧形成化合物第8章第1节翻译练习1Thisgasozonegasisfoundsome15to35kilometersabovetheEarth’ssurfaceintheupperatmosphereor“stratosphere”.这一气体(臭氧)位于地球表面上空大约15-35公里的大气层或“同温层”Airloadcanbeplacedinequilibriumwithinertiaload.气动载荷可以与惯性负载相平衡Whenopposingforcesbalanceeachotherastateofequilibriumorbalanceisreached.当两个反方向作用的力相互抵消时,便达到平衡状态第1节翻译练习Themicrowaveisfeaturedbywidebandandtheabilitytopenetratehighaltitudeionospherewithoutobstruction.微波的特点是频带宽可无阻碍地穿过高空大气电离层Thedeckofthetriple-hullsubmarineissituatedmuchlowerandinconsequencebetterutilizationofspaceispossible.三层船壳潜水艇的甲板位置要低得多,因而有可能更好地利用空间Microscopecontinuestobeaveryimportanttoolinsciencetoday.显微镜仍然是今日科学中很重要的工具Suchwavesoccurmostfrequentlyatstormylatitudeswherethestormstendtocomeingroupstravelinginthesamedirectionwithonlyshortperiodsseparatingthem.首先,我们有可能注意到,有一系列附加因素在加速这一过程第1节翻译练习3Astheflightspeedincreasestherecomesapointwheretheflowreachesthelocalspeedofsound.随着飞行速度的增加,这一流动可能会达到局部音速Thewheelisconsideredtobeoneofthegreatesttechnicaladvancesinhumanhistory.轮子是人类历史上最伟大的技术进步之一Thereisconfusionoverthedifferencesbetweenbasicandappliedresearch.基础研究和应用研究之间的区别分辨不清Incontrasttoconductorsthereareveryfewfreeelectronsinaninsulator.与导体完全不同,绝缘体中自由电子很少Considerationshouldbegiventotheamountofwearlikelytotakeplacebeforethenextinspectionfallsdue.必须考虑到下次检修之前可能发生的磨损量Likethegasolineenginethedieselenginegenerallyisconstructedwithseveralcylinders.像汽油机一样,柴油机通常也有数个气缸第1节翻译练习4Glassdoesnotconductelectricityneitherdoestheair.玻璃不导电,空气也不导电Theelectricpowercanbetransmittedeitherbymeansofd.c.ora.c.电既可以直流传输,也可以交流传输AtthenextstationtheangryconductorputEdisonandallhisthingsoffthetrain.到了下一站,气冲冲的列车员把爱迪生赶下了火车,并把他所有的东西都扔了下去第2节翻译练习1Thetechniqueisusedtodetectflawsinequipment.该项技术被用来探测设备的缺陷Conductinganelectriccurrentmeanstransmittingelectrons.传导电流就意味着传送电子Controloftherefrigerationprocessissimplifiedbytheuseofaliquidsubcoolingcontrolvalve.冷冻过程的控制可采用一个液体过冷控制阀而得到简化第2节翻译练习2ThatwinterIdidnotknowtheprinciplesofworkofthismachinenottospeakofdesigningit.那年冬天,我连这台机器的操作原理都不懂,更不用说设计这种机器了Theyworkedoutnewcontrolelementsmakingtheoperationmucheasier.他们研制出了新的控制元件,从而使操作容易多了Hesaidhewouldcheckupandrepairthesetransformers.他曾说过他要检查和修理这些变压器第2节翻译练习3Therewillbemoreandmoretelephonesinthefuturesandtheywillbebetterones.将来会有越来越多的电话机,而且它们将更好Decisionsaboutsitesilvicultureandgeneticswillaffectharvestvolumeandlogandwoodproperties.有关场址、造林术和遗传学的决策将会影响产量以及圆木和木材性质Fossilfuelswillcontinuetoactastheprincipalfuelsourceinthefirstquarterofthe21stcentury.矿物燃料的21世纪在头25年里将仍然是主要的燃料来源第2节翻译练习4Inrecentyearsscientistshavefoundchemicalsthataffectmoodmemoryandotherhappeningsofthemind.近年来,科学家们已经发现了一些会影响情绪、记忆、以及其他精神活动的化学物质Somemakershavealreadymovedto17-inchmodelsastheirfocuswhileothersarekeepingtheattentiononthe15-inchline.有些制造商已经将注意力转移到17英寸显示器的生产,而其他一些制造商则仍主要生产15英寸显示器EnvironmentCanadahasalsoinventedaverysensitiveinstrumentthattakesozonelayermeasurementsfromtheground.加拿大环境部门已经发明了一种十分敏感的检测仪,它能从地面测量臭氧层数据第2节翻译练习5Nowattemptsarebeingmadetoincreasetheproportionofelectricallypoweredvehiclesontheroadparticularlybymanufacturinganordinarymotorcarthuspowered.目前正试图增大道路上电动车辆的比例,特别是要生产电动的普通汽车Todaytheroleofneuropeptidesinhumanbehavioriscreatingmuchinterest.目前,神经肽对于人类行为的作用正在引起人们的很大兴趣Peoplearestilltalkingaboutthehistoriceventsoflastweekwhenthefirstspacemencircledtheearth.人们还在谈论上星期的历史性事件,第一批太空人环绕地球飞行第3节翻译练习1Waternecessaryfortheseedtogerminate.种子发芽需要水分Itisvitaltoensurethatapatientisnotoneoftheminoritybeforecuttingintohisrighthemisphere.在对大脑右半脑进行手术之前,确信病人不是那些少数人之一是非常重要的Itisusuallybesttoavoidsubstitutionofnumericalvaluesuntilthefinalformulahasbeenobtained.在得到最后公式之前,最好不要代入数值Itisratherdifficulttodefinethisquantityprecisely.对这个量要精确地下定义是相当困难的Whenreadingathermometeritisessentialtoholdtheinstrumentinanuprightpositionotherwisethereadingmaybewrong.读取温度计示数时,一定要使温度计保持直立的位置Itisoftennecessarytomultiplyaquantitybyitselfanumberoftimes.常常需要将一个量自乘若干次Itisdifficulttoremovetheimpuritiesfromthesolution.很难将溶液中的杂质去除Thephenomenonisdifficulttoexplain.这个现象很难解释第3节翻译练习2Theideahereistolocateintheweatherrecordsconditionsthatareasanalogoustothecurrentconditionsaspossible.灯泡底座的两个接触头通过灯座借以传送电流Onewayinwhichcostscanbeminimizedinmanufactureorconstructionistousestandardparts.将生产或制造成本降低到最低限度的一种方法就是采用标准部件Theonlywayahomecomputercaneffectivelydealwiththehugeamountsofdatarequiredforgoodqualityvideoistocompressit.家用电脑有效处理高品质视频所需大量数据的唯一途径就是压缩第3节翻译练习3Theuseofparallelcircuitsmakesitpossibletoswitchanylightorapplianceonoroffwithoutaffectingothercircuits.使用并联电路使我们可能开关任何电灯或电器而不影响到别的电路Therebeesandhummingbirdshelppollinateplantsandacolonyoftermitesaidinthedecompositionofdyingmaterial.在那里,蜜蜂和蜂鸟有助于给植物传授花粉,成群的白蚁能促进枯萎的枝叶分解Theyforgottoincludesomeotheralloyingmetalsintothealloy.他们忘了在合金中放入某些其他的合金金属第3节翻译练习4Thestudyofthermodynamicsenablesustopredictwhichprocessesorreactionsmightoccurspontaneously.对热力学的研究使我们能够预计哪些过程或反应可以自发的进行Shortcircuitswouldcauseverystrongcurrentstoflow.短路会使得很大的电流通过ThenewinformationledscientiststoassumethatVenusrotatesonitsaxisveryslowly.这一新信息使科学家们设想,金星及其缓慢地饶轴自转第3节翻译练习5Thecarrierwaveismodulatedtotransmitthesignal.通常用微粒除尘机控制粉尘污染Thesparkistimedtooccurbeforethepistonreachestopdeadcenterotherwisemaximumpressurewouldnotbereachedintime.火化应定在活塞到达上死点之前出现,否则不能按时达到最大的压力Turbinebladesmustbeproducedtowithstandcreepandcorrosion.绝缘体用来把电流限制在所要求的路线中第3节翻译练习6Eventhoughtheozonelayerisaninvisibleshieldscientistshavefoundanumberofwaystomeasureit.臭氧层是一种不可见的保护层,不过科学家们已经找到了多种测量它的方法Peoplearesearchingforthenewandbetterwaystopreventfactoriesfromsendingoutpoisonousgasesandpollutedwater.人们正在寻找防止工厂排放有毒气体和污水的新的更好的方法Therewassimplynovisibleevidencetosupportsuchatheory.根本看不到有任何明显的证据来支持这一理论第3节翻译练习7Togetagreatamountofwaterpowerweneedlargepressureandcurrent.要得到巨大的水力,就需要高水压和大流量Allairwouldbepassedthroughacleaningsystemtoremovedustparticlespollennoxiousgasesandotherpollutants.所有的空气都通过净化系统来消除灰尘、花粉、有害气体及其他污染物Theproblemsincludethedevelopmentofprocessescatalyticconverterseffluenttreatmentfacilitiestominimizethereleaseofordeactivateproductsharmfultotheenvironment.问题包括开发加工技术(催化转换器、污水处理设施)以尽可能地减少排放对环境有害的物质,或使有害物非活性化Thiscausesthebelttowedgeitselfintothegroovetoincreasethefriction.这就使得本身契入槽中,以增大摩擦Aresistorisplacedparallelwithanotheronlytomakethecurrentgreater.一只电阻箱与另一只电阻器并联,从而使电流变大Sophisticatedtechnologydevicesfordisabledpeopleareoftenexpensivetobuyandtoproduce.供残疾人使用的先进技术设备的生产成本和购买价格往往很高第3节翻译练习8Thankstofastprintersandcopiersproducingahigh-qualitydocumentonpaperhasbecomemucheasier.由于高速打印机和复印件的出现,制作高质量纸张文档变得极为容易Eliminatingpopularmisconceptionsaboutdisabilitycanalsoplayaroleinenablingthevisuallyandhearingimpairedtoliveonequaltermswiththesightedandthehearing.消除普遍存在的对残疾人的错误看法也有助于使视力和听力损伤者与耳聪目明的健康人平等的生活Increasingitsdiameterwilldecreasetheresistanceofawire.加大导线的直径会降低其电阻第3节翻译练习9Arcweldingismakingmetalstogetherbymeansofanelectriccurrent.电弧焊是利用电流把金属溶解在一起Onebasisofabiometricverifierisanalyzingthedynamicsofthewayapersonsignshisorhername.生物统计学核实器的一个基本点的分析一个人签名时的书法笔力Theaimofdocumentmanagementsoftwareisreducingtheworkloadandimprovestheproductivityofmostoffices.文档管理软件的目标就是要减少大多数办公室的工作量并提高工作效率第3节翻译练习10Weavoidedusinganexpensivecomponentbyredesigningthecircuit.我们重新设计了电路,避免了使用一种昂贵的元件Themajorityofalloysarepreparedbymixingmetalsinthemoltenstate.大多数合金是将熔态的金属混合制成Acleanmachinegivesallconcernedthefeelingorproducingahigh-qualityprintingproduct.一台洁净的机器给各有关人员的感觉是能生产出高质量印刷产品第3节翻译练习11Mountingthepanelmodelonashortstruthastheadvantagesofdecreasingthetaredragofthesetup.把翼片模型安装在一个短支柱上,其优点是减少了安装支架的阻力Therearefourwaysfortransmittingpowerfromtheelectricmotortothespindle.有四种方法可以把动力从电动机传到主轴Animportantconsiderationinmakingresistancecalculationsistheeffectoftemperatureonresistivity.在进行电阻的计算时,应重点考虑的一点就是温度对电阻率的影响第3节翻译练习12Themajoradvantagesofthetransistorasusedinelectroniccircuitsarelightweightsmallspacelowpowerconsumption.使用在电子电路中的晶体管的主要优点是重量轻、体积小、耗电量低Associationisthebasisofconditionedreflexes.心理联想是条件反射的基础Submarinescanassumeanydesireddepthbetweenthesurfaceandtheseafloorbychangingtheirdensities.潜水艇通过改变自身的密度可以达到介于海面与海底之间所期望的任何深度Theneedforafter-treatmentcanbeavoidedbyusingbetterpreparedfeedstock.利用一种较好的、经过特别处理的原料,就可以不必进行后处理Specialistsinallbranchesofmechanicalengineeringarekeenlyawareofthenecessityofreplacingmachineswithperiodicoperationbycontinuouslyoperatingmachines.机械工程各部门的专家们都深深感到必须用连续操作的机器来代替间歇操作的机器Theamountofheatgivenoutbytheheaterincreasesindirectproportiontothelengthoftimetheheaterison.加热机器所放出的热量与加热器开的时间长短成正比Robotswillbecarryingoutmanytasksatpresentcarriedoutbymen.机器人将完成目前由人来做的许多工作Thetestspecimenpreparedfromthetestsamplesselectedfromcopperrodsshallmeettherequirementsofthisstandard.用从铜棒中选取的试样制成的试件必须符合本标准的技术要求Theonlysemiconductorelementusedinearly1940s-stylemicrowavecircuitswasthecrystaldetectordiode.在20世纪40年代早期微波电路使用的唯一的半导体器件是晶体检波二极管Theproductshouldpassalltheenvironmenttestsasspecifiedinthetable
6.产品应用通过表6所规定的全部环境试验项目Infactmaterialsasusedintransistorsdonotexistinnaturebutareman-made.实际上,晶体管中所用的材料是人造的,在自然界中并不存在Curvedsurfacesmayreflectlightregularly.曲面会规则地反光Whenevercurrentflowsinacircuitcontainingresistanceavoltageappearsacrosstheterminalsoftheresistance.每当电流流过具有电阻的电路时,电阻两端之间会出现电压Automationmakesskilledlaboravailableformorecreativeoccupation.自动化技术使熟练的劳动者能从事更有创造性的职业Thetypicalproblemofcircuitandnetworktheoryistodeterminethecurrentscausedbytheapplicationofagivenvoltagetoagivencircuitornetwork.电路和网络理论的典型问题是确定将一定电压加于一定电路或网络所引起的电流第3节翻译练习13Pigironcontainsanumberofimpuritiesincludingcarbonfromthecoke.生铁含有一些杂质,其中包括来自焦炭的碳Everycranehasacertainliftingcapacityrangingfromafewtonstomanyhundredsoftons.每台起重机均有一定的起重力,该起重力从几吨到几百吨不等Theelectricchargeswhichflowinmentaltoformwhatiscalledelectriccurrentareelectronsbelongingtometalatoms.在金属中流动从而形成所谓电流的电荷属于金属原子的电子第3节翻译练习14Ifoundthespringremovedfromthemachineunharmed.我发现此弹簧从机器上拆下以后没有损伤Awattofpowerwillkeepacurrentofoneampereflowinginacircuitunderapressureofonevolt.一瓦电能使一安培电流在电压为一伏的回路中流动第3节翻译练习15ObservedinunaccelebratedreferenceframesNewton’sfirsttwolawshold.在非加速的参照系中作观察时,牛顿第
一、第二定律才能成立Havingbeenwellinsulatedthewiremaybeusedasaconductor.经过良好的绝缘之后,金属线可用作导体Havingreachedboilingpointwatervaporizesmorequickly.水在达到沸点之后,蒸发得越来越快Whenmakingidentificationsbiometricsystemsreadinauser’scharacteristics.进行身份鉴定时,生物统计学系统读入使用者的特征第3节翻译练习16Lookingatacrosssectionofawaterwavewemayseethatitisperiodicincharacter.如果观察水波的横截面,我们就会发现水波具有周期性Livinginaspaceshuttlehumanbeingswillmeetwithsomeproblemssuchasweightlessnessandlackingofoxygen.假如人类生活在航天飞机上,就会碰到失重和缺氧等问题Usingatransformerwecanincreaseordecreasethevoltageofanalternatingcurrent.如果使用变压器,就可以升高或降低交流电的电压第3节翻译练习17Suchareactioncanbeverydangerouscausingthecutoffofyouroxygensupply.这种反应可能造成很大危险,因为它能切断你的氧气供应Designedtobeearthquake-proofthetunnelcanmovelaterallyupanddownorslideendwise.由于是按防震要求所设计的,这条隧道可以左右、上下移动或向两端延伸第3节翻译练习18Possessingmanyexcellentfeaturesthethree-phaseinductionmotorisnotavariable-speedmachine.三相感应电动机虽有许多优点,但不是变速电机Highlymechanizedthefoodandtextileindustriesstillrelyonthehumansensesforcertainessentialoperations.食品业和纺织业虽已高度机械化,扔依赖于人的感官来进行某些重要的工序Consideredadifficultmaterialtoweldaluminumisinfactoneofthemostreadilyweldableofallmetals.肃然铝被认为是一种难焊的材料,事实上确实所有金属中最容易焊接的金属之一第3节翻译练习19Bricksareproducedinstandardsizesmakingthemeasytohandle.通常的砖都具有一定的尺寸和规格,这样容易砌筑Itshotinnermostconstituentsdriftedfartherinwardenlargingtheprotosun.星云盘最里面的高温部分进一步向内漂动,使原始太阳增大Theexpandinggasrotatestheturbinethusgivingupalargepartofitspower.膨胀的气体转动涡轮机,从而放出了大部分的动力第3节翻译练习20Usingamagneticorelectricfieldtheemanationsfromradioactiveelementscanbeseparatedintothreecomponents——alphaparticlesbetaparticlesandgammarays.发动机可以是气冷式的或是水冷式的,后者更为常见Dependingontheirmethodoffunctioningadistinctionisbetomadebetweenhydraulicandmechanicalpresses.根据其工作方法,可以把压力机区分为水压机和机械压力机Batsflythroughthedarkestnightsnothittinganythingexcepttheirintendedtargets——monthsandotherflyinginsectswhichthebatshuntandeat.蝙蝠在漆黑的夜晚飞翔,除了想要捕捉和吞噬目标——蛾子和其他飞虫——之外,不会碰到任何东西第3节翻译练习21Thevoltagebeingkeptconstantthecurrentvariesinverselywiththeresistance.电压保持不变时,电流和电阻成反比Simplesubstancesconsistofatomseachsubstancehavingitsspecialatoms.简单物质都由原子组成,每种物质都有它特有的原子第4节翻译练习1All-mentallocknutscanwithstandtemperaturesabove300C全金属自锁螺母能耐300度以上的高温Thenetworkcantakecareofitsowndevices.这种网络能监控自身的设备Wecanreadilyvisualizeanobjectcarryingacharge.我们能够很容易地观察到一个物体带电Heatcannotflowspontaneouslyfromacoolertoahotterbody.热决不会自发地从低温物体流向高温物体AsshowninFig.8theresultantcurrentcouldnotfalltozero.如图8所示,合成电流决不会降至零Withexpensiveeditingcomputersyoucouldeditvideojustlikeadocumentwithcuttingandpassing.使用昂贵的编辑用计算机,你可以像编辑文档一样编辑视频材料,对其进行剪切和粘贴Abeamofelectronscanbebentbypassingitbetweenamagnet’spoles.使一束电子通过磁铁的两极之间,可使电子束方向偏斜Thiscanhardlyhappenunlessthefueltankisbroken.这种情况几乎不可能发生,除非油箱破裂第4节翻译练习2Incoldweatherwatermayfreezeintheenginecoolingsystem.在寒冷的天气里,发动机冷却系统中的水可能会凝固Anexcessivepressureofsteammightcausetheboilertoexplode.过高的蒸汽压力可能会引起锅炉爆炸Therearepeptidesthatmaychangeorimproveforexamplecreativityintelligenceimaginationandmemory.有些肽可能改变或提高诸如创造力、智力、想象力和记忆力Butifthestarisverylargemuchbiggerthanoursunthisprocessofshrinkingmaybesointensethatablackholeresults.但是如果这种恒星很大(比太阳大得多),它的收缩过程可能非常剧烈,结果产生黑洞Imadeaholehereinorderthatthetemperatureinsidethecasemightbemeasured.我在这里打了一个洞,以便测到盒子里面的温度Wemayillustratemolecularmotioninliquidsbythefollowingexperiment.我们可以通过以下试验来说明液体中的分子运动Pleasetesttheinsulationofthewiresothatwemaybesureitissafetouse.请试验一下这根导线的绝缘性能,以使我们确信导线可安全使用Ifawaycouldbefoundtoharnessthereactionstheymightbeusedtomakevaluablechemicalproducts.假如能找到一种利用这些反应的方法,这些反应或许能用来生产贵重的化学制品Weretherenoelectricpressureinasemiconductortheelectronflowmightnottakeplaceinit.如果半导体没有电压,半导体内就不会产生电子流动第4节翻译练习3Thedrugmustbetakenatexactlytherighttimeandintherightdosesandareonlytherudimentaryprecursorsofaneventualjet-lagorshift-workpill.必须完全准时并严格按计量服用这些药,而且这些药只不过是未来的飞行时差或轮班工作药的初级形式Thecurrentratingofthecablemustnotbeexceeded.不得超过电缆的额定电流Theoilpressuremustnotbeunderthescaleotherwiseitwillbringgreatdamagetotheengine.油压不得低于刻度要求,否则会引起发动机严重损坏Thismustbeinterpretedasasignofhypothyroidism.这只可能解释为甲状腺机能减退的一种现象Theremustbesomethingwrongwiththatgenerator;itdoesnotwork.电机肯定出了毛病,它不工作了Theunitsmusthavebeeninstalledbynow.机组现在一定安装好了第4节翻译练习4Needwemakeanyadjustmenttothismeterbeforeapplication使用之前我们有必要调试这台仪器吗?Thiscircuitcableneednotberatedatanymorethan23A.这条电路电缆的额定值不必超过23AOncethereactionhasstartednomoreexternalheatneedbeapplied.反应一开始就不需要外部加热了第4节翻译练习5Economiccontractsshallbeinwrittenform.经济合同必须采用书面形式Anoticenotsmallerthan65mmby50mmshallbefixedtothecontainermarked“DangerHighVoltage.’在外壳上必须钉上一块面积不小于65mmX50mm的标牌,上写“高压、危险”字样Thetemperaturerangethroughwhichtheequipmentshalloperateis180°to90°.设备的工作温度一定要在180度到90度之间第4节翻译练习6Sometimesweshouldhavethestressesatdirectionsotherthanthosegivenbytheequations.有时要与公式所定的方向不同的应力Weshouldchoosetherightmotorforeachkindofworksincemotorsofdifferenttypesdifferintheircharacteristics.既然不同类型的电动机的性能有别,我们应该按不同工种来选用适当的电动机Shipsshouldnotdischargeoilintotheopensea.船舶不得把污油排入公海Asparesetofbrushesshouldbeofproperrating.一套备用电刷应有适当的定额Providedthatthecostisreasonablethisdesignshouldbeaccepted.倘若成本合理,这项设计有可能被采纳Shouldtherebeurgentsituationpressthisredbuttontoswitchofftheelectricity.万一有紧急情况,请按红色按钮以切断电源Shouldthecurrentbecutoffthecoilwillreturntoitsoriginal.一旦切断电流,线圈即恢复到原来状态Weuseinsulatorsforfearthatelectricityshouldleakawayfromthewire.我们使用绝缘体,以免漏电Wemustcheckandrechecktheresultsofourexperimentslestthereshouldbeanyerrorsinthem.我们必须反复核对实验结果,以免发生差错Electrochemicalmachiningshouldhavebeenbetterthanmechanicalmethodsofmentalremoval.用电化加工方法本应该比用机械方法切削金属的效果好Youshouldnothavekeptthosecellsinthedampplace.你本不该把那些电池放在那块潮湿的地方第4节翻译练习7Thecomputerwillbepreprogrammedtodrawmacros.计算机可按预编程序绘出宏指令表示的内容Itmaywellbethatspeedalonewillnotbethemainemphasisinthefutureaviationdesign.在未来的飞机设计中,很可能不再单单强调速度Mostpeoplewoulddescribewaterasacolorlessliquid.多数人会把水描述成无色的液体Partreplacementwilldecreaseifmachineadjustmentsarecheckedonaregularbasis.假如机器调试精度得以定期检查的话,那么零件的更换也会减少TogetherwewilltakeactionbyphasingCFCsandotherozone-depletingchemicalsoutofourlives.总的来说,我们可以采取行动,在我们的生活中逐步停止使用氟利昂和其他消耗臭氧的化学品Withoutitsatmospheretheearthwouldhaveaveryhighdaytimetemperature.假如没有大气层,地球白天的温度将会很高Soundwillnottravelthroughvacuum.声音不能通过真空Iftheenginecouldbemadetoworkinthiswayitwouldhaveanefficiencyof100%.假若能使发动机这样来工作,它会有100%的效率第5节翻译练习1Fortransmittingrotarymotionandtorquearoundcornersbevelgearsarecommonlyused.为了使转动和转矩能绕道传递,常常使用伞齿轮Thetypesofroofsaregenerallyspeakingdividedintotwothesebeingflatandpitched.通常,屋盖可分为平屋顶与坡屋顶两种Theelementvaluesofthefiltermaybechosenasdesired.滤波器的额定值是可以任意选取的Sometypesofpneumoniacan’tbetreatedwithantibiotics.有些类型的肺炎是不能用抗生素治疗的ThepumpisdesignedspeciallyforusewiththeDoxfordengine.这种泵的设计专门用于与多克斯发动机配合使用第5节翻译练习2Theproblemwassolvedbyaddingacapacitor.安装一个电容器就解决了这一问题Thistypeofsystemwasrequiredbybuildingwithlargeglazedareas.装配玻璃面积很大的建筑需要安装这种系统Avehiclewasdevisedafewyearsagowhichpermittedmovementoverdifficultlandandcouldflyforashortdistance.几年前人们设计了一台能在难以行走的土地上移动并能短距离飞行的交通工具Attemptshavebeenmadetousefuelcellsforcentralpowerstationsbutwithlittlesuccess.人们所进行过的将燃料电池用于中心电站的尝试都未获成功Radioactivityisfoundonbothsidesofthefailureplaneinallcases.在任何情况下,破断面的每一翼面都发现有放射性Three-phasecurrentshouldbeusedforlargeindustrialequipment大型工业设备应使用三相电流.TigersarefoundinIndiaandmostofthecountriesofSoutheastAsia.印度以及东南亚地区的大多数国家都有老虎Ifoneisdiscoveredtohavedevelopedhighblood-pressureorheart-diseaseheisimmediatelytransferredtolightwork.如果发现谁得了高血压或心脏病,就立即调他去做轻松的工作第5节翻译练习3Foranymachinewhoseinputandoutputforcesareknownitsmechanicaladvantagecanbecalculated.对于任何机器来说,如果知其输入力和输出力,就能求出其机械效益Reinforcedconcreteroofsareoftenconstructednowadaysespeciallywherethereisariskoffire.从防火要求考虑,目前多采用钢筋混凝土屋顶Analmostidenticalcrackingproblemwasencounteredintheproductionofcast713turbineblades.在生产712铸造汽轮机叶片时,碰到了一个几乎相同的裂纹问题第5节翻译练习4Whencurrentismadetoflowthroughacoilthesortironcoreismagnetized.当电流通过线圈时,软铁心便被磁化Thetermisusedtodescribeaninterlinkedsystemofdocuments.该术语被用来描述文件连接系统Atomsinmoleculesareboundbycovalentbonds.分子式的原子被共价键所束缚Thespeedofageneratoriscontrolledbytheprimemover.发电机的转速受原动机控制Withouttheozonelayerplantsandanimalswouldalsobeaffected.如果没有臭氧层,动植物也将受到影响第5节翻译练习5Allelementsaremadeupofatomswhichinturnaremadeupofelectronsprotonsandotherminuteparticles.所有单质都有原子组成,而原子又由电子、质子及其他微小的粒子组成Allthealternativeroutesaregiventocardriversbycomputers.所有供选择的路线都由计算机显示给汽车司机ThetransistorwascreatedbytwoBellscientistsBrattainandBardeen.晶体管是由贝尔实验室的两位科学家布拉顿和巴丁发明的Entireepochshavebeennamedformaterials.人类往往用某种材料来命名一个时代Hisequipmentismadefromflatpiecesofcopperandaluminumarrangedsothatelectricitycangothroughthem.他的设备是用几片扁平的铜片及铝片组成的,其组合方式可让电流通过第5节翻译练习6Thisprocessischaracterizedbythesmeltingreductionfurnacewithtwo-stagetuyeresofacokepackedbedtype.这种工艺是以使用带两极风口的焦炭填充床的熔融还原炉为特点的Oilisdischargedfromthetankbyapump.油是靠泵压从罐中放出的Microwavecircuitse.g.couplersamplifiersoscillatorsdetectorsetc.wereintensivelydevelopedduringtheWorldWartwotomeetthepressingmilitarydemandsofradarinparticular.在第二次世界大战期间,为了满足急迫的军事需求,尤其是对雷达的需求,微波电路(如耦合器、放大器、振荡器、检波器等等)得到了极大的发展Problemsshouldberesolvedingoodtime.有问题要及时加以解决Thesecirculationanomalieshavelongbeenrecognized.这些环流异常现象早就为人们所认识Thismethodwasadoptedforthefollowingreasons.之所以采用这种方法,有以下几个原因Steeliswidelyusedinengineeringforitspropertiesaremostsuitableforconstructionpurposes.钢之所以广泛地用于工程中,因为钢的性能非常适合于建筑使用第5节翻译练习7Veterinaryservicesshouldnotbeconsideredaluxury.不应把兽医服务看成是一项奢侈服务Inthecaseofanorbitingspacevehiclecentripetalforeisappliedtothevehiclebytheearth’sgravity.当宇宙飞行器沿轨道运行时,地球的引力把向心力作用于飞行器上Whensuchmotorsareusedtheyareusuallybuiltintotheequipmentbythemachinerymanufacturerasinportabletoolsofficemachineryandotherequipment.这类电动机的使用通常是由机械制造商把它们直接安装在设备中,如便携式工具、办公机械及其他设备第5节翻译练习8Naïveratsandfrogsaresaidtohavereactedwildlytosuchproposedenvironmentalchange.据说首次用来做实验的鼠和蛙对这种拟定的环境改变都有剧烈的反应Itisgenerallyacceptedthatirradiationisdestructivetohumantissues.一般认为,辐射对人体组织是有害的Ithasbeenobservedthatforalongtimeitwasincorrectlybelievedthatcurrentflowedfrompositivetonegative.我们已经注意到,人们过去长期错误地认为电流是由正极流向负极的Itisnowknownthatfoodproteinisnotabsorbedassuchbutmustfirstbebrokendownintoconstituentamino-acids.人们已经发现,食物中的蛋白质不能按其原来的形式加以吸收,必须首先分解为氨基酸总复习题Thestatoroftheinductionmotorismadeupofalaminatedsilicon-steelcoreandastatorwinding.感应电动机的定子由硅钢片制成的铁芯及定子绕组构成Sinceairhasweightitmustpressdownonthesurfaceoftheearth.由于空气具有重量,它必定对地球表面有压力Computerlanguageisbasedonthebinarysystem.计算机语言以二进制为基础Thiselectricalpressureactsmuchlikewaterinatank.这种电压的作用很像是水箱中的水压TheSpirothermequipmentgivestheoperatoragoodpictureofthetemperaturedistributionoverthetopoftheburden.利用Spirotherm装置,操作者可获得一个较好的炉顶物料温度分布图Againthestainlesssteelsdonothavethissecondcharacteristicbutmostmetalsdo.另外,不锈钢不具备这第二种特性,但大多数金属都具备Severalresearchgroupsareconcentratingonfindingnewmethodsofdeliveringdrugstothebody.几个研究小组都在集中精力探索向人体释放药物的新方法Itisfrequentlyadvantageoustostakethesurveyinglinesperpendiculartotheknownorpresumedgeologicalstrike.(在做物探测量时)将侧线垂直于已知的或者假定的地质走向标出,通常是比较有利的Itisimpossibletosecurerealeconomicandpoliticalindependenceofacountrywithoutdevelopingitsheavyindustry.不发展重工业不可能确保一个国家经济和政治的真正独立Itisnecessarytohaveaverylargeheatingsurfacewithintheboiler.锅炉里面必须有很大的受热面AccordingtoAlbertEinsteinitispossibletochangemassandenergyintoeachotherwithoutaloss.根据爱因斯坦的观点,质量和能量可互相转换而没有任何损耗Inthiswayitispossibletomakestrongmagnets.用这种方法可以制造出很强的磁铁Suchabearingisdesignedtoprovidelubricationtoreducefriction.这样的轴承用来提供润滑以减少摩擦Thehoppermachinegivesasubstantialincreaseinloadingrateasagainstthestandardloader.与一般的装载机相比,这种漏斗车可以大大提高装载速度Thereducedpressurecausestheinletvalvetoopen.压力降低使得进给阀门打开GasesexhaledbyvolcanoesbecametheatmosphereofVenusEarthandMars.火山喷出的气体形成了金星、地球和火星的大气层Theoperationallowssurplusenergytobeused.这道工序可以使剩余的能量得到利用Weburnfuelsinenginestomakethemwork.燃料在发动机里燃烧以使机器工作Oneoftheobjectsofawelldesignedcircuitistoavoidinterferencebetweencomponents.设计良好的电路所要达到的目的之一便是避免元件之间的干扰Inonekindoftransistortherearethreewiresfastenedtothecrystalofgermanium.有一种晶体管,在锗晶体上面牢系着三根导线IntheUnitedStatesthecustomaryvoltageforhouseholdusehasbecome110-120Vsinceitwasdiscoveredthathighervoltagescouldcausefatalaccidents.美国通常的家用电压是110-120伏,因为人们发现,更高的电压会造成致命的事故Plantheightwashighlycorrelatedwithmaturityindicatingthatpopulationwithshortstemstendstobeearlyinmaturity.植株的高度与成熟期有密切的关系,这说明矮秆群体往往会早熟Allotherconditionsbeingequalweshouldfirstadjusttheinstrumentto“zero”.其他条件相同的情况想,我们应先把仪器调整到“零位”Inthe1930’sitwasfoundthattheatomcouldbesplitreleasinghugequantitiesofenergy.20世纪30年代人们就发现原子可以分裂并释放出大量的能量Ontheotherhandowingtothesmallerfurnacethegasutilizationandthermalefficiencymightbecomelow.另一方面,由于炉子小了,气体的利用率和热效率可能要降低Anequipmentfailureoraccidentonthemooncouldhavelefttheastronautsstranded.在月球上如果有一种设备失灵或出事会使宇航员们束手无策、进退两难Inordertokeeptheinstrumentinagoodstatereadyforuseatanytimeitshouldgothroughnecessarycalibrationregularly.为确保仪器经常处于良好的可使用状态,平时必须定期对仪器进行必要的检测Iftheropeshouldbreakthepulleywouldfalldown.一旦绳子断了,滑轮就会掉下来Sometimesitisdesiredthatboththedriverandthedrivenwheelrotateinthesamedirection.有时希望主动轮和从动轮都向同一方向转动Itwillbeappreciatedthatthenecessityofprovidingacommutatorwithitscarbonbrushescomplicatestheconstructionofthemotor.我们可以理解,必须给换向器装备碳刷会使电动机的结构复杂化Aninterestingmachinehasbeenmadetoreplaceworkersfordangerousjobs.已造出一种有趣的机器代替工人做危险的工作Ceramicshavelongbeenlimitedbytheirbrittleness.易碎这个弱点长期以来限制了陶瓷的发展Investigatorssuspectthattheviruswasbroughtintothecountrythroughwastefood.调查人员怀疑,食品垃圾把这种病毒带入了该国第9章第1节翻译练习1Hydraulicspringsareparticularlysuitedforapplicationsinwhichhighloadcapacitiesandstiffnessarerequired.液压弹簧尤其适用于要求承载能力和刚度很高的地方Wecanregardtheentireweightofabodyasconcentratedatitscenterofgravity.我们可以认为物体的整个重量像是集中在物体的重心上Installingtheelectronicunitsinthegroundandleasingtelephonewireswouldcost$15million.安装地下电子装置和租借电话线就要耗资一千五百万美元Introductionofanewly-developedtechniquewillenhancetheprospectsofsuccess.引进一项新开发的技术将增加成功的希望第1节翻译练习2SincethelinesofmagneticforceconvergeanddivergethereisthenecessityforacomponentBr.由于磁力线的汇聚和发散,就必须需要一个分量BrAttemptshaveevenbeenmadetorenametherobot.人们也一直在尝试给机器人重新命名第1节翻译练习3Severalconceptsareintroduced:decision-makingmodelingdynamicsfeedbackstabilityandlogicaldesign.这里介绍几个概念判定、模拟、动力学、反馈、稳定性和逻辑设计等Provisionismadewithinthecircuitrytolimitthetransistorvoltage.电路已采取措施来限制晶体管的电压Seetoitthatalltroublesshouldbeeliminated.务必要排除所有故障Nodirectelectricalconnectiontotherotorisprovided.转子没有直接的连接电线Thehinge-pinreactionsarefoundbytakingasummationofthehorizontalandverticalforces.分别求出水平方向和垂直方向各力之和,即可得铰销反力Uptonowtherehavebeenthreemainoptionsforencodingamessage.迄今为止,消息的编码有三种主要的选择Provisionmustbemadefordissipatingtheheatthatresultsfromtheslidingofsurface.必须采取措施驱散因表面摩擦所产生的热Itcanbeconcludedthatcopperoxideisamorestablecompoundthanmercuricoxide.我们可以断言,氧化铜是比氧化汞更为稳定的一种化合物Fromthisexperimenttheconclusionisdrawnthatthetheoryofoppositelychargedparticlesattractingeachotheristrue.由这一实验可以得出结论,带异性电荷的粒子相互吸引的这一说法是正确的第1节翻译练习4Theexperimentsaredesignedtovalidatehistheory.这些试验的设计是用来证实他的理论的Goodclockshavependulumswhichareautomaticallycompensatedfortemperaturechanges.好钟的钟摆可以自动补偿温度的变化Anatomofoxygenis16timesasmuchasanatomofhydrogeninweight.一个氧原子的质量相当于一个氢原子质量的16倍Asemi-conductormaterialispoorerthanaconductorinconductivity.半导体材料的导电性比导体的差第1节翻译练习5Thecollapseofthedamcausedthelandbeingflooded.由于水坝倒塌,土地因此被淹没Restrictedmovementledtoaninterruptionofbloodflow.由于活动受限制导致血液流动受阻第1节翻译练习6Anyfrictionbetweentwosurfacesresultsinatemperatureriseofthematerials.两个表面之间的任何摩擦都会导致材料的温度升高Therivetscontractastheycooldrawingtheplatestogether.铆钉随着冷却而收缩,从而使钢板紧紧地压在一起Andthedirectioninwhichthesoundistravelingtellsthebatwherethemealislocated.同时,声音传播的方向能告诉蝙蝠事物的位置第1节翻译练习7Theexperimentresultedinthediscoveryofacureforcancer.这一实验的结果是发现了一种治疗癌症的方法Theapplicationofsurfactantsaimstosimplifyworkprocesses.使用表面活性剂的目的就是简化工作工程第1节翻译练习8Weightvariesslightlyindifferentplacesoftheearthdependingontheforceofgravity.物体的重量在地球上的不同地点都会稍有变化,它取决于引力的大小Thedialisscaledintoonehundredgraduations.该标度盘刻有分成100等分的标度第1节翻译练习9Thepressurewasdeterminedtobe
0.1torr.所测得的压力为
0.1托Thepowerstationmanagedtomaintainitssupplyofelectricitydayandnight.电站尽力地保持日夜供电第1节翻译练习10Measurementofthelateralstraincanbeaccomplishedusingalateralextensometer.侧向应变可用侧向伸长计来测量Anybodywhichiscapableofdoingworkisconsideredtopossessenergy.任何能做功的物体都具有能量第1节翻译练习11Themomentwhenlightleavesadistantstarandthemomentwhenitreachesoureyesarenotsimultaneous;theymaybeseparatedbymillionsofyears.光离开遥远的恒星的时刻和它到达我们眼睛的时刻不是同时的,期间可能相隔几百万年Thebasicgoalofhigh-definitiontelevisionistoincreasethenumberoflinesinatelevisionpicturethussharpeningit.高清晰度电视的基本目标是增加电视图像的扫描线数量,从而使图像清晰Anaddedbenefitisthatlessnoiseisgenerated.一个附带的好处就是所产生的噪音小第1节翻译练习12Carbondioxideisdenserthanair.二氧化碳的密度比空气大Rubberisabetterdielectricbutapoorerinsulatorthanair.橡胶的介电性比空气好,但绝缘性比空气差第1节翻译练习13Ifyou’rewatchingagameintheballparkthenetworkwillknowthatplayerprofilesarewhatyouneedonyourpalm-sizedcomputer.如果你在球场观看一场比赛,网络会知道你希望掌上电脑提供的是每位球员的简介Oneofthewell-knownlawsofphysicsisOhm’sLaw.欧姆定律是物理学上著名的定律之一Itisamatterofcommonexperiencethatitismucheasiertorollbodiesalongthantoslidethem.通常的经验是物质向前滚动比向前滑动容易得多第1节翻译练习14Thesenewmachinesarenowinwideuse.这些新机器正在被广泛使用Thesumofthepowerdissipationisequaltothepowerdeliveredbythecurrentsource.总共消耗的功率等于电流源发出的功率第1节翻译练习15Asmostmetalsaremalleableandductiletheycanbebeatenintoplatesanddrawnintowire.由于大多数金属都具有延展性和韧性,所以可以压成薄板和拉成细丝Theangular-contactbearingisofgreaterthrustcapacity.向心推力轴承具有较大的轴向承载能力第1节翻译练习16Theironintheshipcausedadeviationofthemagneticneedleofthecompass.船体里的铁引起指南针磁针的偏离Allmovingbodieshaveenergy.所有运动的物体都具有能量第1节翻译练习17Aradioantennashouldhaveaphysicalsizeofone-halfwavelengthormore.无线电天线的实际尺寸应为办个波长或更大一些Animalsandplantshavecharacterswithvariation.动植物的特性是可变的Thereareradioactiveisotopesofeveryelementeitherthoseexistinginnatureorelsethoseactivatedartificially.每一元素都有放射性同位素,或是天然存在的,或是人工激活的Theseproblemsarestillofprimaryconcerntopresent-dayphysicists.现代物理学家对这些问题仍然非常关心第1节翻译练习18Manualfirealarmstationareinstalledoneachflooratthestairstobeusedforfirenotificationbythebuildingoccupants每层楼的楼梯处装有手动消防警报器,便于楼内住户通知火情Itallhelpstheclaimthattherawmaterialforlifewasimportedfromthecloudsofspace.所有这些都有助于说明形成生命的原料是从星际空间的尘云输入的第1节翻译练习19Thismuscle“balancing”canhelppostureandpromotemoreefficientmovement.这种肌肉的“平衡性”能帮助校正姿势,促进更有效的运动Beingagoodinsulatorrubberstronglyresistscurrentflow.橡胶是一种良好的绝缘体,它能基本组织电流的通过第1节翻译练习20Theabilitytocontrolyourqualitylevelisimportantfordesktopvideoproducers.控制品质水平的能力对桌面视频制作者是十分重要的Internalheattrappedbythegasesfiredupaprotosunandignitedthermonuclearreactions.被气体封住的内部热量点燃原始太阳,激起热核反应第1节翻译练习21Therearetwodifferentkindsofelectricitywhichwecallpositiveelectricityandnegativeelectricity.电有两种正电和负电Therearedifferentformsofenergy:heatenergylightenergysoundenergymechanicalenergyelectricalenergyetc.能有各种不同的形式热能、光能、声能、机械能和电能等Therearetwogroupsofmetals:puremetalsandtheiralloys.金属有两大类,纯金属及其合金第1节翻译练习22Mathematicshasthesameeducationalfunctionasclassicsusedtohave.数学现在所起的教育作用和过去古典著作一样Copperhasveryhighconductivity.铜的导电率很高Whenyouturnalightorelectricapplianceofftherewillbeelectricvoltagebuiltupattheswitchbutnocurrentwillflow.当关上电灯或者电器时,在开关上有电压产生,但是没有电流流动ItisasetofprogramsgoverningthewayinwhichmultimediafilesarecreatedanddisplayedontheInternet.它是一套程序,这些程序控制着因特网上多媒体文件的建立和展示的方式第1节翻译练习23InthisbookIhavegivenspecialprominencetothelawsthatgoverngravity.在这本书里,我特别强调了那些支配引力的定律Abriefdescriptionofhowtransistorsaremanufacturedisgivenhere.这里扼要地讲讲晶体管是如何制造的Thistypeofspringisextensivelyusedinelectricalinstrumentsanddeservesspecialconsideration.这种弹簧广泛地应用于电工仪表中,因此值得专门地考察一下Incopperandmostpuremetalsthereisanappreciableincreaseinresistancewithanincreaseintemperature.在铜和大多数纯金属里,随着温度的升高,电阻也会明显地增大Whenaneworrepairedmachineisabouttobeputintoserviceathoroughexaminationformechanicaldefectscannotbecancelled.一台新机器或修好的机器投入使用时,必须仔细地检查有无机械缺陷Whatworriesnuclearphysicistsisthesafedisposalofnuclearwaste.令核物理学家担忧的是如何安全地处置核废料第1节翻译练习24Inordertokeeptheenginespeedwithinthelimitswhichitwasdesignedforadevicewhichisknownwasagovernorisincorporatedintheengine.为了把发动机的速度保持在设计的范围之内,发动机内装有一个叫做限速器的装置Onlyafewmetalsareusedcommerciallyintheirpurestate.只有少数几种金属以纯态被用在工商业上Theheatsupplywasinadequatetomaintaintheliquidasitsboilingpoint.热的供给不足以使液态保持在其沸点第1节翻译练习25Quasi-starsbroadcastpowerfulradiowaveswhichmayvaryinstrength.类星体不断发出强大的无线电波,其强度可能各不相同Inductionmotorsaresimpleindesignsturdyinconstruction.感应电动机设计简单,结构牢固Aboveacertaincriticaltemperaturesteelwillchangeinstructure.超过某一临界温度,钢的结构便会发生变化第1节翻译练习26Intheatmospheretheratiobyweightofthenitrogenandoxygenvariesslightlyaboutanaverageof3:2:
1.大气中的氮和氧按重量的比例平均约为3:2:1Thetemperaturecoefficientoftheresistanceispositiveformetalsandnegativeforsemiconductors.金属的电阻温度系数的正的,而半导体的是负的第2节翻译练习1Theindifferencecurvehadnocurvatureatall.无差异曲线根本没有弯度Theinactivegasneitherburnsnorsupportscombustion.惰性气体既不能燃烧,也不助燃Castironisnoteasilyrepairedbyweldingorbrazing.铸铁(制品)不易用熔焊或钎焊法修复Blowingmethodisnolongerpossibleespeciallyinthecaseofthickworkpieces.尤其是厚工件,已不可能采用喷吹法第2节翻译练习2Computersarenotwellsuitedtomanipulatepicturesorothergraphicdata.计算机不很适合于处理图像或其他图示数据Frictionisnotonlyundesirable.摩擦并非总是不需要的AnelasticmaterialdoesnotnecessarilyobeyHooke’slaw.并非任何一种弹性材料必定符合胡可定律第2节翻译练习3Suchglasswouldbendlikemetalwhendroppedratherthanshatterbits.这种玻璃掉在地上会像金属一样弯曲而不碎裂Thismachineappearstobeoutoforder.这台机器似乎不正常Aquickrealitycheckconfirmsthatthecomputerfarfromreducingtheamountofpaperhasactuallyincreasedit.实际情况明显反映出计算机不仅没有减少纸张用量,相反却使之增加Thespeedandversatilityoftheearliestcomputersweregreatlyinferiortothoseofamodernmicrocomputer.早期计算机的速度和通用性远不如现代的微型计算机第2节翻译练习4Despiteitsmanyadvantageswoodarenotwithoutitsdrawbacksasafuel.尽管木材有许多优点,但作为燃料不是没有缺点的Withoutsubstancetherecouldbenoworld.没有物质就没有世界Noflowofwateroccursunlessthereisadifferenceinpressure.没有压差,水就不会流动Intheabsenceofelectricitylargescaleproductionisimpossible.有了电才可能进行大规模生产Alltheseelectricprotectivedevicesshouldnotbeunboxedorunwrappeduntilthemomentforfittinghasarrived.要等到安装这些电气保护装置时才可打开包装箱或包装盒第2节翻译练习5Therearefewtosupporttheviewthatinahighlyefficienttransitoperationalmosteveryvehicleshouldbecapableofrunningalmosteveryservice.很少有人赞成这样的观点,即在高效的交通运输作业中,几乎每一种机动车都应能够完成几乎所有的服务功能TheyfoundthattheozonedamageovertheArcticwasmuchlessseverethanthedamageovertheSouthPoleandthattherewaslittleincreasedrisktopeoplelivinginthefarnorth.他们发现,北极臭氧层的破坏远不及南极厉害,这使得生活在北极地区的人们几乎没有增加危险第2节翻译练习6Nosignificantdifferencebetweentheexperimentalandcontrolbirdswasobserved.没有观测到实验鸟和对照鸟之间存在明显的差异Theobjectdidnotmovebecauseitwaspushed.该物体移送,不是因为有人推了它Thecircuitshouldbeoverloadedonnoconditions.电路在任何情况下都不得过载EvenintheSouthPolenoactualholeexists.即使在南极也不存在实际的(臭氧)“空洞”Wedon’tthinkitonlyahypothesis.我们认为那不仅仅是一个假设Wedon’tconsiderthatneutronshavecharges.我们认为中子不带电Atnotimeandundernocircumstanceswilltheybethefirsttousenuclearweapons.他们在任何时候和任何情况下都不首先使用核武器总复习题Heascribedthisdisagreementtotheoversimplifiedmodel.他把这种不一致现象归因于模型过于简单Nowironandsteelmakingprocessesarenowreexaminedworldwide.现在世界范围内开始重新审视炼铁和炼钢工艺Thisdiseaseisresponsivetotreatmentwithdrug.药物治疗这种病有良好的疗效Distilledwaterisneededinthelaboratoryinlargequantities.实验室里需要大量的蒸馏水Safetyprecautionsshouldbeobservedatalltimes.任何时候都应遵守安全预防措施Thewinghasaflatundersurfaceandacurvedtopsurface.机翼的下表面是平的,上表面是弯曲的Thereexistmanysourcesofenergybothpotentialandkinetic.势能和动能都有许多来源Intheskymanyplanetarysystemsmustbeentirelylifeless.天空的许多行星系必定是无生命的IftheneedlefailstoremainatzeroreadjustcontrolNo.
1.若果指针不能保持在零的位置上,应重新调整一号控制器Theearthwasnotbelievedtoberoundbutflat.人们曾经认为地球是扁的而不是圆的Notenoughpowercanbegotoutofthesingle-stagesockettogetthesatelliteuptowhereitshouldbe.从单级火箭上不可能获得足够的功率把卫星送到所需的位置第10章第1节翻译练习1Wecouldusetworesistorsinseriesorwecouldincreasethevalueofthepresentsingleresistor.我们可以用两个串联的电阻,或者我们可增加现有的一个(电阻)的电阻值Displacementisavectorandtimeisascalar.位移是一种矢量,而时间是一种标量Industrializationenablescountriestoraisetheirstandardsoflivingbutitisalsonecessarytoimprovemethodsofagricultureaswell.工业化能使国家提高其生活水平,但是也必须改进农业生产方法第1节翻译练习2Thetemperaturewouldhavecontinuedtogoupbutthatfeedbacktookplace.要不是发生反馈的话,温度会继续上升Theaveragekineticenergyofthemoleculesisincreasedandthetemperatureisraised.分子的平均动能增加了,因而温度也升高了Theoutputpowercanneverequaltheinputpowerfortherearealwayslosses.将铅化合物加进汽油中以提高其辛烷值,从而也提高了发动机的性能第2节翻译练习1Wherethisnewtoolofinvestigationwillultimatelytakeusisbeyondmypowersofprediction.这一新的研究工具最终将把我们带至何方,我无法做出预测Amorecarefullypreparedexperimentwouldbepossibletoconfirmyourtheory.更加精心准备的实验有可能证实你的理论Whetherlifecanexistonanyplanetotherthantheearthisverydoubtful.除地球外的任何别的行星上是否存在生命,是很值得怀疑的第2节翻译练习2Itislikelythatallthepowderwilldissolveatonce.全部粉末可能一下子全部溶解Itisnolongeranecessaryconsequencethatanobjectthrownintotheairmustfallbacktoearth.射入空中的物体一定会回到地面上来,这已不再是必然的结果Itisquitenaturalthereforethatallmodernmachinesshouldpreferablyemploycontinuousrotarymotioninsteadofperiodicreciprocatingmotion.所以,现有现代机器都尽量采用连续的回转运动来代替周期的往复运动,这是很自然的Itisstilltobediscussedwherethenewsubstationwillbebuilt.新变电站建在什么地方仍有待讨论第2节翻译练习3Weuseinsulatorstopreventelectricalchargesfromgoingwheretheyarenotneeded.我们使用绝缘体来防止电荷跑到不需要电荷的地方去FaradayandHenryweretryingtodiscoverwhetherelectricitycouldbeproducedfrommagnetismasamagneticfieldwasproducedbyanelectriccurrent.法拉第和亨利都曾试图揭示,电是否可像磁场由电流产生那样由磁产生Onemightaskwhythescientistfeelssocertainoftheexistenceoftheseparticles.人们可能要问,科学家对这些粒子的存在为什么感到如此肯定第2节翻译练习4Onthemoonanastronautwillweighonlyonesixthofwhatheweighedonearth.宇航员在月球上的体重只有在地球上体重的六分之一Wefeedtheprogramandthedataintoaninputdevicefromwheretheyaretakenthroughthecontrolunitintothestore.我们将程序和数据送入输入设备,从那里通过控制器把它们送入存储器第2节翻译练习5Theconsequenceofheatingagivencopperrodisthatitundergoesoxidationandformsanoxide.加热一条铜棒的结果是它会氧化并形成一种氧化物Thecuttingspeedofthetooliswhatmatters.刀具的切削速度才是重要的Theassembly-lineofthefactoryiswhereallthecomponentsareputtogether.工厂的装配线是将所有的零部件装在一起的场所Thefirstthingweneedtofindoutiswhetherwatercontainsair.我们需要弄清楚的第一件事是水是否含有空气第2节翻译练习6Attheendoflastcenturyanimportantdiscoverywasmadethateverythingwaspartlybuiltofelectrons.上世纪末有一个重要发现,即一切东西都有一部分由电子组成In1905Einsteinworkedoutatheorythatmatterandenergywerenotcompletelydifferentthings.1905年,爱因斯坦提出了一个理论物质和能并不是完全不同的东西第2节翻译练习7Theproposalthatmoreequipmentshouldbeimportedfromabroadistobediscussedatthemeeting.会上将讨论从国外进口更多设备的建议Theproblemthatallmachinesinthisfactorymustbecontrolledbycomputerswillbesolvedbeforelong.该厂所有机器实现计算机控制的问题,不久就能解决第2节翻译练习8Atthattimeonlyafewscientistsacceptedtheideathattherehadbeenalargeislandinwhatisnowthedeepestpartofthissea.那时,只有少数几个科学家认为现在的这个海域最深的部分曾经有过一个大岛Anoutstandingadvantageisthefactthattheaxialclearanceisnotlimited.其突出的一个优点就是轴向间隙不受限Wewereworkingonthesuppositionthattheycouldimprovethecomplexmachine.我们认为他们能改进这台复杂的机器第2节翻译练习9Somenecessarymeasureswereadoptedinviewofthefactthattheeventhadhappenedunexpectedly.由于事态的意外发生,我们采取了一些必要的措施Despitethefactthatyouarenottheonlypersontoblameyouareprincipallyresponsibleforit.你虽然不是唯一承担过失的人,但你要负主要责任第2节翻译练习10Obviouslytherewaslittleprobabilitythattheywouldsucceedinelectrolysis.很明显,他们在电解方面成功的可能性是很小的ThereisnocertaintythattheelasticmaterialdoesnotnecessarilyobeyHooke’slaw.人们不能确定,这种弹性材料是否符合胡可定律Therearealsosuggestionsthatblackholescouldbeusedtocreatebombsinthefuturebyamplifyingradiowavessentuptothem.还有一些建议,认为通过把发射到黑洞的无线电波增强,将来有可能利用黑洞制造炸弹第3节翻译练习1Itisparticularlyusefulforasphericopticsproductionwhereordinarypolishingkinematicsistotallyunsuitableforaspherics.它特别适用于加工传统机械抛光无法做到的非球面光学产品Cloningdoesn’tnecessarilymakecellsgrowoldandcanevenactasafountainofyouthsayresearcherswhohavebeeninvestigatingagroupofclonedcalves.克隆牛犊的研究者们宣称克隆不一定非使细胞老化不可,它甚至可以成为长生不老的源泉Asystemthatmimicsphotosynthesisefficientlymaybe50yearsaway.一种能有效地模拟光合作用的系统的出现可能还需要50年第3节翻译练习2TheyrapturouslycommendedthefaultlessorganizationoftheaerialsiteandtheskillofEiffel’sengineerswhoamongstotherachievementshadperfectedaspecialdesignofcraneGuyrnettypethatmovedverticallyalongtheliftrails.他们兴高采烈地赞扬高空作业工地无懈可击的组织工作和埃菲尔铁塔的工程师们高超的技术这些工程师的成就之一是完善了一种特殊设计的起重机(居耶钠型),这种起重机能沿着升降机轨道垂直移动AsreportedrecentlyinScienceresearchersattheUniversityofNotreDameareworkingonamethodofbuildingcircuitsthatneedonlyatinyinitialelectricalchargetotransferinformation.根据《科学》杂志最近的报道,诺查丹玛大学的研究人员正在开发一种电路设计方法,它只需微量的初始电荷便可以传输信息Thesoundtoberecordedispickedupbyamicrophonewhichtransformssoundwavesintoimpulsesofelectriccurrent.所要记录的声音为传声器所接收,后者将声波转变为电流脉冲Alreadylasergunsarebeingdevelopedwhichcouldkillanenemyorbringdownanairplaneoramissileatagreatdistance.人们已在研制各类激光炮,这些激光炮能远距离杀死敌人,击落飞机或导弹Athermometerisatubeclosedatbothendswhichcontainsaliquid.温度计是一根两端密封,里面装有某种液体的玻璃管Thesungivesusheatwithoutwhichtheearthwouldbeafrozenworldinwhichnolifecanexist.太阳给我们提供热,没有这种热地球将会成为生命无法生存的一个冰冻的世界第3节翻译练习3Laseristhemostpowerfuldrillingmachinebecausethereisnothingonearthwhichcannotbedrilledbyit.激光器是打孔能力最强的钻机,因为它能给世上的任何物体钻孔Therearemanysubstancesthroughwhichcurrentswillnotflow.许多物质不导电Howevertherearemanyinstanceswhereadditionaltestsareneeded.可是,在很多情况下需要进行附加测试第3节翻译练习4Inadomino-likeeffectthechargeofthefirstofthefirstcellinthecircuitchargesallthecellsthatfollow.好像多米诺效应一样,电路中第一个电池的电荷能够使后面所有的电池充电Agoodunderstandinghasbeenobtainedofevaporationprocesseswhicharecarriedoutatordinarypressure.人们对于常压下的蒸发过程已有了清楚的了解Intheearlydaysoftheclippershipssailorswhowentonlongvoyageswouldoftengetadangerousdiseasecalledscurvy.在使用快速帆船的初期,远洋海员们往往会患一种叫做坏血病的危险疾病Thehardnessofthesteeldependsonthepercentageofcarbonitcontains.钢的硬度取决于其含碳量第3节翻译练习5AcommoncomplaintoftravelagentsisthatEuropeanswhoaccountforover40percentofthetouristtrafficexpecttoseeallofIndiainafortnightinthesamewaythattheymaytrytoseeItalyorFranceinaweek.旅游业经理的共同抱怨是占游客总数百分之四十以上的欧洲人希望能有在一周内游览意大利或法国的那种方式,在两周内游览全印度TheresultwhichhavejustbeenreportedtoBritain’sMedicalResearchCouncilshowthatsomeofthediverswhowereapparentlyhealthyhadareasofbraindamagesimilartothosefoundinstrokevictims.最近提交给英国医学研究委员会的检查结果报告表明这些潜水员中有些人虽然表面上看起来很健康,但脑部有些区域出现同中风病人类似的病灶第3节翻译练习6Forheavymulti-storeyblocksbuiltonpoorsoilthefoundationoftenconsistsofawatertightreinforcedconcreteopenboxwhichalsoformsthebasement.若要在土质差的地方建高层建筑,经常采用不渗水的混凝土箱型基础,它也是地下室的一部分Whenacrystalmeltsdisorderisproducedintheparticleswhichlosetheirfixedlocationsinthecrystallattice.当一种晶体熔化时,粒子中便产生无序现象这些粒子便失去其晶格中的固定位置Massistobedistinguishedfromweightwhichismeasuredbythepullofgravityonabody.应把质量与重量区分开,后者是根据对物体的引力来测定的Thetransistorisacurrent-controlleddeviceasdistinctfromthevacuumtubewhichisavoltage-controlleddevice.晶体管是一种电流控制器件,它不同于真空管,后者是电压控制器件第3节翻译练习7Thesunheatstheearthwhichmakeitpossibleforplantstogrow.太阳使地球变暖,这使植物生长成为可能Anation’slevelofdevelopmentcanmeasuredbyitsabilitytoproducefoodandfiberwhichrelatestotheirexpertiseintheareaofCropandSoilSciences.一个国家的发展水平可以通过它生产食品和纤维制品的能力来衡量,这涉及到其在作物与土壤学领域的专门技术Liquidwaterchangestovaporwhichiscalledevaporation.液态水变为蒸汽,这就叫做蒸发第3节翻译练习8Worldpopulationisincreasingataratewithwhichfoodandotherproductionmaynotbeabletokeepplace.世界人口在迅速增长,使得粮食和其他产品可能无法跟上其增长的速度Thedrillshouldbebackedfromtheworkfrequentlywhichallowsremovalofchipsandpassageofcoolant.应经常后退钻头,以便能除去钻屑并使冷却液通过Andatthesametimetheywouldfoilgenepirateswhowouldseetheirstolengoodsdisappearbeforetheirveryeyes.同时还能挫败基因窃贼,因为他们会眼睁睁的看着他们偷来的东西就在眼前消失掉StrontiumisnamedforStrontianaScottishvillagewhereorecontainingiswasfound.锶是以一座叫做斯特朗西恩的苏格兰村庄命名的,因为含锶的矿石就是在那里发现的Cancershouldbesuspectedinpersonswhohaveanyofthesesymptomsandsignsforunaccountablecausesandforanunreasonableperiod.如果病人具有任何这些症状和体症,病因难以说明,而且持续时间过长,就应怀疑病人换了癌症第3节翻译练习9Evenifourmeasurementsshowthesamevelocityoverdifferentsectionsitmaybeassertedthatthemotionisuniformonlywiththedegreeofaccuracythatthemeasurementsweremadewith.虽然自动化机器有很多优点,但它们只能做人们吩咐它们要做的事Theinterpretationwhichisnotentirelyconvincingisatleastpartlytrue.这种解释虽不完全令人信服,至少有几分真实性Anyonewhohastuggedheavyhandbaggagedownendlessairportcorridorsorwaitedforadelayedflightinasterileloungewillknowhowuser-unfriendlymanyairportsareindesignterms.任何人当他拖着沉重的随身行李,走过无止境的机场走廊,或者在枯燥乏味的休息室里等候延误的班机,都会体会到许多机场在设计上对旅客是多么不方便第3节翻译练习10Thefactsofsciencearenotassomethinkdryandlifeless.与某些人想象的相反,科学上的某些事实并不是那样的枯燥无味和没有生命力Thepatientdidnothaveaheartattackasthedoctorhadfeared.与医生担心的相反,患者并没有复发心脏病第3节翻译练习11GlaxoWellcomeisdevelopingamethodofvaccinedeliverywherethevaccineisattachedtotinygoldparticles.格莱索·威尔克姆正在开发一种疫苗释放方法,即将疫苗粘附在微金粒上Astronomersandscientiststhinkthatablackholeisaregionofspacenotathingintowhichmatterhasfallenandfromwhichnothingcanescape——notevenlight.天文学家和科学家认为黑洞不是一种物体,而是太空的一个区域,即物质掉进去后,任何东西,甚至于光,都无法逃出第3节翻译练习12EpisodesoflowcardiacoutputwhichwereaccompaniedbysignificantincreasesinPAP/AOPratiooccurredin20patientsandweremanagedbyalterationandadministrationofpulmonaryvasodilators.在20个患有低心输出血量发病的患者中,伴有肺动脉压和主动脉压比率明显增加,其处理方法是改善通气并给以肺血管扩张剂Theceramicwillbemadeofoxidepowdersusingtechniquesthatmustbecarriedoutonlyinanatmosphereofultra-pureandinertnitrogen.这种陶瓷用氧化物粉末制成,所采用的工艺必须在超高纯度和超高惰性的氮气中才能进行NewevidencetobepublishedlaterthismonthinthejournalScienceoffersasimpleexplanationwhytwolaboratoriescametoclaimcreditforthesamediscovery.本月晚些时候将在《科学》杂志上公布新的证据,就为什么两个实验室对同一个发现都要求荣誉权的问题提供一个简明的解释第3节翻译练习13Puttingarestrictiononthedepthtowhichadivercandescendmightbehelpful.对潜水员下潜的深度实行限制也许是有益的Nowhereinthewholedomainofthemotionsofthenaturalworldhaveweyetfoundanycasetowhichtheanalysisofmechanicsdoesnotapply.在自然界的整个运动领域里,我们还没有发现力学分析不适用的任何情况Thisisanincandescentbulbthelightofwhichtravelsinalldirections.这是一盏白炽灯,它的光是向四面八方传播的Someelementsareknowntheatomsofwhichusuallydonotcombinewithmorethantoneatomofanyotherelement.某些元素是众所周知的,这些元素的原子通常不能同其他任何元素的一个以上的原子相结合Airisamixturethecomponentsofwhichareofgreatuseinthechemicalindustry.空气是一种混合物,其成分在化学工业中大有用处第4节翻译练习1Asweobserveobjectsaroundusoneofthemostnoticeablepropertiesistheirmotion.当我们观察周围的物体时,最显著的特性之一是其运动性Whenanobjectissuspendedbyasinglestringitisobservedthatthestringhangsvertically.当一物体用一根细绳悬挂起来时,可以看到绳子垂直的挂着Whenoneformofenergydisappearsotherformsappearinequivalentamounts.每当一种形式的能量消失时,就会出现等量的其他形式的能量第4节翻译练习2Ourwholephysicaluniversewhenreducedtothesimplesttermsismadeupoftwothingsenergyandmatter.我们的整个物质世界,如果用最简单的话来说,是由两样东西组成的,即能和物质Wearealwaysabletoknowthethirdonewhenweknowthemagnitudesoftheothertwo.如果已知其中的两个变量,我们就可以求出第三个变量第4节翻译练习3Abodyatrestwillnevermovetillaforcecompelsit.精致的物体在外力迫使它运动之前决不会运动HeatandtemperaturewereconfuseduntilJosephBlackclearedupthesubjectin
1760.在1760年约瑟夫·布莱克澄清了热和温度这个问题以前,人们一直将两者混为一谈SlidelineCtotheleftuntilitcorrespondswithlineD.将线C向左平移,直到与线D重合为止BoilthesolutiontillitbecomesfreeofH2S.将该溶液一直加热到没有硫化氢为止Electriccurrentdoesnotflowinthecircuituntilweaddabattery.直到我们加上电池组后,电流才能在这条电路中流动第4节翻译练习4Onceasatisfactorysystemoflubricationhasbeensecuredthehardnessoftheinteractingelementsbecomescritical.一旦获得了满意的润滑系统,相互作用的元件的硬度就成为了关键因素Onceairborneparticlestoucheachothertheycombineintoabunchofparticles.空气中的粒子一旦彼此相碰,就结合成一个粒子团Ifalltheimpendingforcesofgravitationandresistancecouldberemovedthereisnoreasonwhytheballonceitisinmotionshouldeverstop.如果一切起阻碍作用的引力和阻力能被除去,就没有理由认为,球一旦处于运动中会再停下来第4节翻译练习5Sincethearcburnsinaclosedvolumeahighgaspressurewillbeobtained.因为电弧在一个密闭容器中燃烧,将得到很高的压力Sincefromnowonfrequentreferencewillbemadetosampleandpopulationitisnecessarytodistinguishbetweenthemeanofasampleandthemeanofpopulation.因为从现在起要常常提到样本和种群,所以有必要把样本和种群的均值区分开来Theresultsoftheinvestigationwerenotconclusivesincethecrucialexperimenthadbeenperformedonlyonce.研究的结果还不是结论性的,因为决定性的实验只进行过一次第4节翻译练习6Wherethereisnoneedforelectricalisolationanauto-transformerissometimesemployed.在不需要电绝缘的地方,有时使用自耦变压器Whereonlysmallavariationinoutputisrequiredsynchronoustapchangingisoftenused.在要求输出电压调节范围较小的电路中,常常采用同步抽头变换法第4节翻译练习7Wherethebearingcapacityisparticularlypoororthequalityofthesoilvariesconsiderablyaraftfoundationisoftenrecommendedtosupportnormalbuildings.若承载力特别低或土质差异巨大,通常用片筏基础支撑一般的建筑物Concretefoundationsneednotalwaysbereinforcedbutwheretheloadtobecarriedishighandtheveeringcapacityofthesoilpoorheavyreinforcementisusuallynecessary.混凝土基础不必总是用钢筋来加固但是,若承受的载荷很大,而且地基的承载力又比较低,通常有必要用钢筋进行大力加固第4节翻译练习8Computertechnologyisadvancingsorapidlythatnobookcaneverbefullyuptodate.计算机技术发展非常迅速,所以任何时候也不可能有一本书能及时充分的反映它的最新成就Gearsplaysuchanimportantpartinmachinesthattheyhavebecomethesymbolformachinery.齿轮在机器中起着相当重要的作用,以致它已成为机械的象征Thebarissetnexttoascrewsothatittouchesthescrewwhenitisstraight.金属棒安装的位置紧靠着螺钉,这样,当金属棒伸直时就碰到螺钉第4节翻译练习9Inorderthatelectronsbeacceleratedinanappliedfieldtheymustbeabletomovetohigherenergylevels.为了使电子能在外加场中加速,电子应能移到更高的能级Thebeltisadjustedsothatitwillfittightlyoverbothwheels.为了减少摩擦,金属表面必须涂上润滑脂Thecompliermustknowitsoperationcodeanditsparametersothataninstructioncanbeassembled.为了能储存大量电荷,电容器通常用大面积的金属板制成Negativeworkshouldbemaintainedataslowavalueaspossibleforanygivenpressureratioinorderthatamaximumamountofusefulworkmaybeobtained.在给定的压力下,负功应尽可能维持在低的数值下,以便获得最大的有用功Iamgoingtostartupthegeneratorincasethepowergoesoff.我去启动发电机,以免断电Setallscrewssotheybearevenlyonlevelingplates.调整各个螺钉,使它们都均匀的压在调平板上第4节翻译练习10Thepressureofagasisinverselyproportionaltoitsvolumeifitstemperatureiskeptconstant.如果温度保持不变,则气体压力和体积成反比Aslongasthecurrentflowsthearmaturewillkeeprotating.只要有电流流通,电枢就会不停的转动Anobserverwillnotseearainbowunlesstherearedropsofwatersuspendedintheair.如果没有小水滴悬在空中,观察者就看不到彩虹Thelawistrueprovidedthatthephysicalconditionsofthecircuitremainconstant.当电路的物理条件不变,这一定律就是正确的Iftheadmissiblegrippingforceisexceededahydraulicoverloadprotectionisoperated.当夹紧力超过了允许值,液压超负荷防护装置就会起作用Wecankeepthesteamengineatworksolongaswehavemeansofproducingheat.我们能够使蒸汽一直运转,只要有办法产生热第4节翻译练习11Electricityflowsthroughawirejustaswaterflowsthroughapipe.电流通过导线,正像水流通过管道一样Exoticplasticsglassandceramicswillshapethefuturejustassurelyashavegeneticengineeringandcomputerscience.奇异的塑料、玻璃和陶瓷无疑将同遗传工程和计算机科学一样塑造着未来Solidsexpandandcontractasliquidsandgasesdo.固体像液体和气体一样地膨胀和收缩第4节翻译练习12Althoughtheseparticlesareverylighttheirenergiesareconsiderablebecauseoftheirhighspeeds.虽然这些粒子很轻,但由于速度很快,因而能量很大Evenifsomeoneisnotaprogrammerhecanhaveagreatimpactonpieceofsoftwarebysuggestinghowtoimproveittothedevelopmentteam.即使一个人不是专业编程人员,他也可以通过向开发小组提出改进建议,而对一个软件产生极大的影响Whilethestarslooklikemerespeckstheyareinrealityenormousbodies.虽然看起来只是些光点,实际上星星都是庞然大物Thoughalittleover100elementsinnaturetheycombinetoformthousandsuponthousandsofdifferentsubstancesintheworld.虽然在自然界中只有100多种元素,可是它们却构成世界上成千上万种物质Nomatterhowsmallastressisappliedtoabodythebodywillyieldalittle.作用在一物体上的应力无论多么小,该物体总会有一点变形第4节翻译练习13Virtualconvergencewilltakethepoweronyourdesktopandmakeitavailablewhereveryouwantit.这种放大器无论信号变化怎样缓慢,都能放大输入信号Theuniquetrainingofthechemicalengineerbecomesessentialintheseareaswheneverprocessesinvolvethechemicalorphysicaltransformationofmatter.只要工艺过程涉及到物质的化学或物理转换,就必然要专门培训化学工程师第4节翻译练习14ItisanticipatedthatLSIchipswillshowtwiceashighareliabilityastheyhavenow.预计大规模集成电路芯片的可靠性比目前可提高1倍Theelectronsmeetlessresistancewhenconductoriscoldthanwhenitishot.导体冷的时候,电子遇到的阻力比导体热的时候小Electronicengineersaremoreinterestedintheapplicationthaninthedevelopmentofsemiconductordevices.电子工程师对半导体器件的应用比对半导体器件的研究更感兴趣第5节翻译练习1WebelievethattheratioismodesthypercholesterolemiasinceindividualswithloworveryhighcholesterolconcentrationsareunlikelytohavetheirriskofdevelopingCHDcoronaryheartdiseasealteredeitherbyHDL-Cmeasurementorthecalculationoftheratio.我们认为这一比率只适用于血胆固醇有些过高的病人,因为胆固醇偏低或过高的人得冠心病的可能性不大会因为他们的高密度脂蛋白胆固醇的高低或这一比率的大小而有所改变Nowateamofastronomershasdiscoveredevidencethattheobjectwhateveritmaybeisspewingvastquantitiesofenergeticparticlesthatcollidewithasurroundingirregularringofcoldhydrogengas.现在,一组天文学家已经发现了证据,即这个天体(不管它是什么),在不断地喷出大量高能粒子,同周围的形状不规则的冷氢气环相碰撞HoweverincasesthathadepisodesofincreasedPAP/AOPratiothemeandurationoffunctionwasincreasedtofivedaysandthiswasalmostcertainlyrelatedtotheuseofcontinuoustolazolineinfusionthroughthecatheter.然而,在患有增加肺动脉压和主动脉压比率的病例中,平均效用时间增加到五天,这几乎肯定与通过导管继续输入抗肾上腺素有关第5节翻译练习2Justasapacesatelliteonceithasgotawayfromthepulloftheearth’satmospherecontinuestocircleroundandroundtheearthforeversoanelectriccurrentcirclingafrozenringofmercuryshouldcontinuetoflowforeverifthetemperatureiskeptbelowtheessentialfourdegreesaboveabsolutezero.如果把冷冻的水银环的温度保持在低于绝对零度以上4度的话,环绕水银环流动的电流就必定会不停的流动正如人造卫星一旦摆脱地球大气的引力,就会永远绕地球运行一样Itisveryinterestingtonotethedifferentlychosenoperatingmechanismbythedifferentmanufacturersinspiteofthefactthattheoperatingmechanismhasamajorinfluenceonthereliabilityofthecircuit-breakers.尽管操作装置对断路器的可靠性具有主要的影响,但注意不同的制造厂按不同形式选择操作装置非常有趣的Thusmarginalcosttotheproducermayfallbelowmarginalcostfromthepointofviewofthewholeeconomywhenextraoutputrequiresextraforeignexchangeandwhenforeignexchangeisparticularlyscarce.以至当生产额外的产品需要额外的外汇,而外汇又很缺乏的情况下,生产者的边际成本可能低于从整个经济角度来看的边际成本第5节翻译练习3Thisdevelopmentisinpartaresultofexperimentalstudiesindicatingthatfavorablealterationsinthedeterminantsofmyocardialoxygenconsumptionmayreduceischemicinjuryandthatreductioninafterloadmaybeassociatedwithimprovedcardiacperformance.从某种角度上讲,这方面的进展是实验研究的结果实验研究表明,心肌耗氧量的决定因素的改善可减轻局部缺血性损害,并且,负荷的减轻也能改善心肌功能Uptoapointflyoversandunderpassesbeingthefirstreallydecisivestepstospeedupanddivertraffichaveeasedthesituationbutaconsiderablecontributiontowardasatisfactorysolutioncanbemadebyundergroundrailwaynetworks.在某种程度上,立交桥和地下道的建设,在加速和分流交通方面迈出了具有决定意义的第一步,从而缓解了交通不畅的局面但要从根本上解决交通问题,仍需依赖地铁系统Inordertounderstandwhathappensduringsinteringofcompactsthechangesindensityindimensionsinmetallographicstructureandinmechanicalpropertiesduringsinteringmustbestudiedfromanexperimentalpointofviewbeginningwiththoseincompactsfromasinglemetalpowderorfromhomogeneoussolidsolutionalloypowders.为了了解用单一金属粉末或同类固体溶解合金粉制成的压坯在烧结过程中发生的变化,必须从实验的观点研究烧结过程中压坯的密度、尺寸、金属结构和机械性能的变化情况第5节翻译练习4Howeverinourexperiencesomepatientsinwhomahighpulmonaryvascularresistancewassuccessfullyloweredbytheabovemeasureshavehadepisodesofincreasedpulmonaryvascularresistancepost-operativelyaccompaniedbyclinicaldeteriorationwhichinsomecaseswasextremelyrapid.然而,根据我们的经验,通过上述措施,某些病人的肺血管阻力成功的降低了,但术后由于临床恶化并在某些病例中发展很快,所以仍有肺血管阻力增高的现象ThenutritionaldilemmaofpersonswithAIDSorPWASisthattheymusteatabundantlyyettheymustalsoavoidfoodborneillnessjugglefoodsandmedicationsandsurmountthepoorappetiteandindigestioncausedbytheirmedicationsandbyAIDSitself.艾滋病患者又称PWAS,他们所遭遇的饮食困境表现为患者一方面必须大量进食,另一方面又不得不防范因饮食而导致的疾病,拒绝零食和用药,还要克服因治疗以及艾滋病本身而引发的食欲不振和消化不良WhatisquestionediswhetheracountrylikeBritainhasachanceassumingithasthewilltosucceedwheresomanyhavefailedandevenassumingthatishasshouldmakethetremendouseffortandtakesubstantialfinancialriskoftryingtoleapfrogintoleadershipinentirelynewtechnologyorwhetheritshouldtakethesofteroptionofmerelycatchingupwiththerestoftheindustrializedworld.问题在于像英国这样一个国家,假定它有决心,是否在那么多的国家已告失败的情况下有取得成功的可能,即使有可能,是否应该做出巨大努力并冒相当大的财政风险,试图在完全新的技术领域跃居领导地位,或者是应该做较为轻松的选择,仅仅赶上工业世界其他国家总复习题Intheearlydaysofthetelegraphandthetelephonemenobservedthatsignalssometimesjumpedthespacebetweenwiresrunningnexttoeachother.在电报及电话发展的早期,人们注意到信号有时会跳过并行导线的空间Tounderstandbothsidesofthequestionsomebackgroundonhowenergyisobtainedfromanuclearreactionmustbestudied.要理解这一问题的两个方面,必须研究有关如何由核反应获得能量的一些基本情况Voyager’sphotographsmayhelpexplainhowtheyNeptune’sringsformed.旅行者号拍摄的照片也许有助于说明这些光环是怎样形成的Ifthewaterisheatedtheparticlesmovemorequicklywhichagreeswithourtheory.如果把水加热,粒子运动就更快,这一现象是和我们的理论吻合的Radiantheatwavespassthroughavacuumbutmaybeabsorbedbybodieswhosetemperatureistherebyraised.辐射热波能通过真空,但能被一些物体所吸收,因而这些物体的温度便升高了Andtherewasthepossibilitythatasmallelectricalsparkmightaccidentallybypassthemostcarefullyplannedcircuit.而且总有这种可能性——一个小小的电火花,可能会意外的绕过了最为精心设计的线路Peopleseethingsdifferentlyinthelightofthefactthattheyarematerialistsandidealists.由于人们的观点有唯物、唯心之分,因而他们对事物的看法也就不同Therewasevidencethatallatomsconsistsofanucleusandelectrons.有证据表明,所有原子都由原子核和电子组成Generallyspeakingwedonotusematerialsintheforminwhichtheyoccurinnature.一般来说,我们并不用自然界中天然存在的那种形态的物质Thesemotorsareasaruleespeciallydesignedforthespecificmachineswithwhichtheyareused.总的来说,这些电动机是为使用它们的专门机器特别设计的Amachinespindlehasdifferentspeedswhichtheoperatorselectsaccordingtothework.机床主轴有几种不同的速度,操作人员可以根据工件进行选用Nowthatwehaveexaminedseveralareasofnaturalscienceperhapsitwouldbewelltoattempttodefinescience.既然我们以考察了自然科学的若干方面,也许不妨可以试试给科学下一定义Sinceanammetermustbeplacedinserieswiththecircuitthelattermustbeopenedforinsertionofthemeter.由于电流计必须与电路串联,故后者必须断开以插入电流计Manyofthemhavemorethanonesolidstatesasinthecaseofphosphoruswhichisknowninthreesolidphase:blackmorefamiliarredandyellowforms.热是能的一种形式,这是大家都知道的Anuclearreactorgetsenergyfromthelossinmassduringthenuclearreactionssowecanconsidermassaformofenergy.核反应堆在核反应期间由质量的损失而获得能量,因此我们可以把质量看作是能量的一种形式Anautomaticproductionlineisexcellentfortheautomotiveindustrywherethousandsofidenticalpartsareproduced.自动生产线很适用于汽车工业,因为那里生存成千上万个同样的零件Ifyouaretravelingforwardinatrainsurroundingobjectsoutsideappeartobemovingbackwards.如果你在一列向前行驶的火车里,外面周围的东西好像是在向后移动Televisionequipmentmakesuseofdevicesthatcanbeconsideredopticalbecausetheydependonlightraysfortheiroperation.电视装置所用的器件可看成光学器件,因为这些器件是靠光线来工作的Ifthelaserdriftsanattemptshouldbemadetoscanthewholefreespectralrangeasfastaspossible.如果激光漂移,则应尽快地尝试扫描整个自由谱区Theadjustmentmustberepeatedeachtimethevesselischanged.每当更换容器时都要重新调整Eachtimetheshortcircuithappenstheshortcircuitcurrentrunsthebatterydown.每当短路发生时,短路电流就将电池的电能耗尽Whenpressureisappliedtoicepartofitwillmelt.假如对冰加压,一部分冰就会融化Anobjectonceitisinmotionwillpersistinthatmotionbecauseofitsinertia.物体一经运动,由于惯性就将继续保持其运动Seeingthatheatcanbeusedtodrivemachinesitisaformofenergy.由于热能够用来驱动机器,所以它是一种能Theblackstainusuallyoccurswherepartsareincontactwitheachother.黑锈斑通常发生在零件相互接触之处Inthesubsequentyearstherewasatrendofhigheryieldsintilledplotsalthoughtheincreasewasnon-significant.尽管在正常的情形下绝缘材料的性能很稳定,但在极端情况下,比如加压过高,高温或在某种化学物质作用下,绝缘材料的性能会遭到完全的破坏Ingeneralthereisameasurabledifferenceinpotentialbetweenthetwoelectrodeswhetherthecellispassingacurrentornot.通常,不论电池有无电流流过,两极之间均具有可测量的电位差Itisevidentthatifinanoxygenconvertercarbonisreplenishedbycontinuousadditionofcoalandtheexothermiccombustionofcarboninthebathisbalancedwiththeendothermicdirectreductionofironoreandthentheconverterwillbeproducingironatacertaincarboncontentinsteadofsteel.很明显,如果在氧气转炉内碳是通过不断地添加煤来补充,而且熔池中碳的放热燃烧与铁矿吸热的直接还原相平衡,那么转炉可以生产含一定碳的铁而不是钢AsshownbySumitomoMetalstheprocessesarenotrestrictedtobottomblowingandacombinationoftopandbottomblowingismostlikelytobechosenespeciallyaspostcombustionoftheCOisamostimportantpossibilityforthefuture.住友金属公司的工作表明,这种工艺不仅局限于底吹,而且将来使一氧化碳产生二次燃烧成为最大可能时,组合式的顶一底吹会成为首选工艺Thestudyofthechemicalsensorswasmainlyconcentratedonthesubjectsofselectivitylifeandcost;i.e.howtodetectaspecificmaterialfromtheenvironmentwheremanydifferentsubstancesco-existselectivity;howtomaintainthesensorintheoriginalconditionlife;andhowtoeconomicallyachievethetargetscost.化学传感器的研究主要集中在选择性、寿命和成本上,即如何在很多不同物质共存的环境中测定某一特定物质(选择性);怎样把传感器维持在初始状态(寿命);怎样经济地实现目标(成本)TheunderstandingofthemechanismsinvolvedintheselectivityandreversibilityofthesensorswouldbeaninterestingsubjectbecauseitrelatestoaphenomenonoflifelikecrownetherandValinomycinwhicharethesimulationofthebiologicallyselectivemembranetheselectionoftheenzymemicroorganismsanti-bodyandorganelleimmobilized.有关传感器的选择性喝可逆性机理的研究与了解将会是一个有趣的课题,因为它与生命现象有关像王冠以太和结氨霉素,它们就是生物选择膜的模拟,也就是酶、微生物、抗体和细胞器官固定膜的选择Deformationisaffectedbythestressinherentinthemetalthemicrostructuralcharacteristicsofthestartingmaterialthetemperatureatwhichthedeformationoccurstherateatwhichthedeformationoccursandthefrictionalrestraintbetweenthematerialbeingforgedandthediesurface.变形会受到金属的内在应力、原始材料的微观结构特征、变形时的温度、变形的速度以及被锻造的材料与模具表面间的摩擦阻力的影响第11章翻译练习1Therootsystemsofterrestrialplantsperformtwoprimaryfunctions:oneistheacquisitionofsoil-basedresourcesprincipallywateranddissolvedionsandtheotherisanchorage.Otherrootsystemfunctionssuchasstoragesynthesisofgrowthregulatorspropagationanddispersalcanbeseenassecondary.Littleisknownoftheearlyevolutionofthenonaerialpartsofplantsbutitiscertainthatmostofthefirstlandplantshadpoorlydevelopedrootsystems.Suchfragmentsasarepreservedareoflargediameterandsparinglyandoftendichotomouslybranched.Sinceearlylandplantsweresmallandlivedinverywetenvironmentsneitheranchoragenoracquisitionofwaterislikelytohavebeenaseriousproblem.Itisquitepossiblethatthemostdifficultfunctionforearlyrootsystemstoperformwastheacquisitionofpoorlymobileresourcesespeciallyphotosphate.陆生植物的根系有两个主要功能一个是获得土壤养分的作用(主要是水分和溶解在水中的离子)另一个是固定作用根系的其他功能如贮存、生长调节剂的合成、繁殖和扩散则被看作是次要功能我们对植物地下部分早期进化了解得比较少但可以肯定的是,大多的早期陆生植物根系发育低现存下来的早期陆生植物的根,直径大而分支较少,常是两叉的由于早期陆生植物小且生活在非常潮湿的环境中,因此植物的固定和吸收水分都不可能成为严重的问题很可能早期植物根系最难起到的作用是吸收养分,因为养分的移动性差,特别是吸收磷酸盐翻译练习2Diesareusuallymadeofcastiron.Thediesshouldbesplitsothatthecoresandthecastingcanbereadilyremovedthecorespreferablyupwardssoasnottointerferewithgasheatingofthedieassemblyfrombelow.Wherethediewillnotbetiltedspruesshouldbeinclinednarrowconstrictedatthebottominfrontofthegateandarrangedtofanoutintothelatteratanangleof45soastoavoidsharpcorners.Severalgatesconnectedbyahorizontalrunnermaybeuseful.模具通常由铸铁制成模具应制成可拆卸型,以确保方便地取出型芯和铸件型芯最好朝上,以保证其不受在模具组建下方进行气体加热的影响模具在使用过程中不倾斜时,应在浇口前方底部设置倾斜,狭窄且缢缩的注入口,并使注入口以45度角展入模具底部,以避免出现急弯有时可能用到由一条横浇道连起来的几个浇口翻译练习3Thesuspensorusedtoberegardedmerelyasananchoragedevicefortheembryobutitisnowregardedashavinganimportantroleinthetransferofnutrientsandplantgrowthregulatorsfromthematernaltissuestotheembryo.过去人们将胚柄仅仅看作胚的固着器,但现在人们认为胚柄在把营养物质和植物生长调节因子从母体组织转移到胚中起着重要作用当然在实验中对胚柄造成的破坏,影响胚的生长在双子叶植物中,胚柄细胞经历了DNA内部复制,也就是DNA复制而核不分裂尽管在植物界这是很普遍的现象,但胚柄代表了极端情况例如,在红花菜豆的胚柄细胞中含有8192倍的DNA(即单倍体细胞中DNA的8192倍)假定这些细胞最初是处于二倍体状态,这么大量的DNA意味着在核不分裂的情况下DNA复制12个周期DNA内部复制的作用我们还完全不清楚翻译练习4Itwasmanyhundredsofyearsbeforeanyfurthersignificantobservationsweremadeaboutthephenomenonofstaticelectricity.Thenitwasdiscoveredthatmanyothermaterialsbesidesambercouldbechargedbyrubbingwhichproducedfriction.Amoreimportantdiscoverywasthatthereweretwokindsofelectricalcharges.数百年过去了,对静电现象的进一步观察才取得突破性成果人们发现,除了琥珀之外还有许多其他材料也能摩擦起电更为重要的发现了两种电荷的存在这两种电荷被称为正电荷与负电荷正电荷用(+)号表示,负电荷用(—)号表示这些符号今天仍然通用人们还发现,同种电荷——同正或同负——相互排斥,而异种电荷——一正一负——则相互吸引人们更晚才知道,是一种叫做电子的物质微粒的移动引起电电子三组成原子的一种微粒,而原子又是组成化学物质的基本单位原子的中心是原子核,几乎包含原子的全部重量或者物质原子核本身由两种不同的微粒,即质子和中子组成总复习题PrecisionForgingPrecisionforgingisnormallytakentomeanclose-to-finalformorclosetoleranceforging.Inthefinalanalysisitisnotaspecialtechnologyofitsownbutarefinementofexistingtechnologiestoapointwheretheforgedpartcanbeusedwithlittleornosubsequentmachining.Theimprovementscovernotonlytheforgingmethodproperbutextendtopreheatingdescalinglubricationandtemperaturecontrolpractices.精密锻造精密锻造通常指近终型锻造或小公差锻造归根到底,它本身不是一项特殊的技术,而是对现有技术的改进它生产的锻件很少经过或不经过后续加工就可以直接使用这种改进不仅包括锻造方法本身,而且扩展到预热、除鳞、润滑和温度控制等是否使用精密锻造技术主要取决于附加锻造操作以及用刀具和取消机械加工之间的相对经济性问题由于刀具开发的成本较高,精密锻造通常仅限于要求产品质量很高的生产中一个使用精密锻造的例子是涡轮叶片,现在它是用不锈钢和其他难以锻造的合金制造的因为轻的叶片连接在相对重的基体上,涡轮叶片的形状不是特别适合于锻造必须进行延长预变形,为实现此目标可以采用不同的生产方法有的制造者通过镦粗其一端的方法生产,还有的挤压足够的材料形成叶片,但是在每种情况下,最后的模槽都是用于提高表面质量和保证较高的尺寸精度AntifrictionBearingsAntifrictionBearingsoperatewithrollingelementseitherballsorrollersandhencerollingresistanceratherthanslicingfrictionpredominates.Thecauseofrollingresistanceisthedeformationofmatingsurfacesoftherollingelementandtheracewayonwhichitrolls.Thethreebasictypesofantifrictionbearingsareballbearingsrollerbearingsneedlebearings.Ballandrollerbearingscanbedesignedtoabsorbthrustloadsinadditiontoradialloadswhereasneedlebearingsarelimitedtoradialloadapplicationsonly.滚动轴承滚动轴承利用滚动体(滚珠或滚柱)来工作,因此占主导的是滚动阻力而非滑动摩擦力滚动阻力的起因在于滚动体的配合面和它滚动的滚道的变形滚动轴承的三种基本类型是滚珠轴承、滚柱轴承和滚针轴承滚珠和滚柱轴承在承受径向荷载之外还可承受轴向荷载,而滚针轴承仅限于承受径向荷载滚动(滚动接触)轴承的一个主要优点在于几乎完全消除了摩擦因此,滚动轴承润滑剂的主要功能是帮助防腐及污垢污染由于确实存在一定的摩擦,尤其是在滚动体与轴承座之间,润滑剂也必须带走这一滑动作用所产生的热,因此虽然有很小的摩擦,但是润滑剂仍然是必要的引起正常润滑的滚动轴承失效的原因是疲劳,它是发生在滚道的接触面或滚动体上的一种应力反向现象这样,滚动轴承的寿命是以疲劳失效前轴滚动的转数来衡量的轴承的载荷越大,其以转数为单位的寿命就越短而且,轴的速度越快,轴承的寿命就越短由于统计中要考虑到疲劳因素,所以也必须考虑失效的百分比概率了解各种类型的轴承的优点与缺点及它们的突出特点很有必要例如,滚珠和滚柱轴承可以是自定位型以便调整轴的对中不准和偏移此外,挡板及密封用于保护轴承以防外来污染物的污染一些滚动轴承内装有密封好的润滑剂,这些润滑剂是由制造商提供的,使得轴承在整个使用过程中得到润滑InSituDesulphurisationPartialremovalofthesulfurvaluesinfossilhydrocarbonfuelscanbeaccomplishedinplaceduringtheapplicationofsocalled“insitu”recoverytechniques.Perhapstheearliestofthesetechniquestobeexploredwasinsitucoalgasification.Duringthe1940’sand1950’sboththeRussiansandtheBritishcarriedoutextensivefieldtrialswithinsitucoalgasificationanddemonstratedthepracticalfeasibilityofobtainingalowBTUgasproductfromtheprocess.MorerecentlyinsitucoalgasificationtrialshavebeenconductedinAlbertaandseveralprojectsintheColoradooilshaleshavefocusedoninsituretortingoftheshaletoliberatethehydrocarbon.Insiturecoverytechniquesusingfiresteamfloodingoracombinationofbothalsoappeartobeoneofthemostpracticalroutesforfluidizingtheheavybitumensofdeeplyburiedoilsandsthusenablingtheirrecoverybydrilledwellsratherthanmining.现场脱硫化石碳氢燃料所含硫的部分脱除可以在实施所谓的“就地”开采技术的过程中完成,这方面最早探索的技术大概是现场煤气化在20世纪40和50年代,苏联和英国都进行了广泛的煤气化的现场试验,证明了此过程获得低BTU煤气产品的实际可行性后来在亚伯达进行了现场煤气化实验另外还有几项对科罗拉多页岩油的开发项目则集中研究对页岩油的现场提纯技术以产生碳氢化合物采用燃烧、蒸汽注入或两者结合的就地开采技术也已经成为深层油砂中的重沥青流体化的最实际的技术途径,从而可以使用钻井法而不使用开矿法来开采这些沥青就脱硫而言,这种原地加工技术的最重要的优点大概在于可以达到需要的化学反应的温度和压力如果在地面进行,则该温度和压力需要负责而昂贵的加工设备方能实现这样可以就地实现化学反应状态,而如果将化石燃料开采出来以后再用传统的方法进行提炼精制,这样做既不切实际又不经济在脱硫反应中这种高温高压条件特别重要地面上的炼焦设备也许可以模拟原地注入燃烧过程的氢转移反应,产生低分子量的碳氢化合物和硫化氢因此,可以达到从有机硫化合物的母体中就地除硫的目标,而且可以出去更易于处理的气态H2SSeedHealthManypestsanddiseasesareseed-transmitted;forexamplethestemandbulbeelwormmaybepassedtotheprogenyviatheseeofAlliumspp.whileceleryleafspotcanbetransmittedbytheinfectedseed.Manyeconomicallyimportantplantviruses——forexamplelettucemosaicvirusandtomatomosaicvirus——areseed-transmitted.Virusintheseedorintheseedcoatcanleadtoearlyinitialfieldinfectionwhichspreadstootherplantswithinthecrop.种子的健康许多虫害和病害是通过种子传播的例如茎线虫和球线虫可能通过葱属植物的种子传播,而芹菜叶斑病能通过感病的种子传播从经济角度讲,许多造成很大经济损失的植物病毒,例如莴苣花叶病毒和番茄花叶病毒是通过种子传播的种子内和种皮内的病毒能导致田间的初期感染,并在同种作物的其他植株间蔓延发展中国家的许多小规模种植者种植他们自己作物留的种子他们常常忍不住从没有销路的作物中采集种子此后导致下一代遗传特性差小规模种植者不使用例如后代检测这样的技术事实上,在一些国家许多大规模生产者也不使用这些相对简单的技术,因此种子改良的可能性,甚至维持原种水平的可能性有时也丧失了NucleusThenucleusisusuallymoreorlesssphericalthoughnucleiwithothershapeshavealsobeenobserved.Thenucleusissurroundedbyandanenvelopeandcontainsthenuclearmatrixandoneormorenucleoli.细胞核尽管也观察到过其他形状的细胞核,但细胞核一般都是接近球形的细胞核被膜包围着而且内含核基质和一个或多个核仁在核质中有由脱氧核糖核酸和蛋白质组成的染色体在染色体中对碱性染料有一定的亲和性的DNA和蛋白质的复合体称染色质在分裂期间(核分裂之间)染色体解螺旋而且不能被分清在这个阶段,在核质中常常可见到浓缩的染色深的染色质团这种染色质称异染色质比异染色质染色浅的染色质称常染色质在分裂期间DNA合成,为染色体的复制过程做准备核膜由两层单位膜组成核膜之间狭窄的空间称核周腔核膜和内质网相连核膜上有一定规律地分布着的核孔。