土木工程专业英语Unit-14-Environmental-Engineeringr-earth课件.ppt

1、：Guess out the following issues Guess out the following issues job job opportunitopportunity yrush hourrush hournoise pollutionnoise pollutionaffordableaffordablehousinghousingLesson B And more graffitigraffitihungerhungerAIDSAIDS What does this video clip tell us?rain forest.avi1.Talk about environ

2、mental problems2.Practise reading skills3.Learn useful words and expressionsObjectivesPart One:Talk about itPicture DescriptionDisappearingNatural Beauties White Pollution Water Pollution Air Pollution Noise Pollution Types of Pollution Animals Living in Harmony Endangeredclearing of the forest Ille

3、gal HuntingDISCUSSIONWhat can we do to protect our environment?For IndividualsThe main environmental problems The causes of the environmental problemsThe effects of the environmental problemsActions and measures to be takenTHINK ABOUT IT Can you name some of the most frequently heard environmental p

4、roblems?global warming;greenhouse effects;the extinction of certain species acid rain,indoor pollution,etc,air/water pollution;waste of energy;Words and Expressions Relating to Environmentdesertificationdeforestationwater and soil erosionindustrial dust dischargemotor vehicle exhaustfossil fuels Top

5、soilsustainable developmentozone layersewage treatment/sewerageEcosystemNonrenewableresourcesenvironment-friendly products bio-degradable plasticAir pollution(空气污染)Water pollution(水污染)Global warming(全球变暖)Sandstorm Hits Hong Kong Air pollution in Hong Kong has hit record levels after a huge sandstorm

6、 swept across northern China over the weekend.For a third day,the Chinese capital,Beijing,was shrouded in a yellow haze,and people who go outside have been warned to wear masks and scarves.Scientists say a combination of drought,cutting down forests and city developments is to blame for these weathe

7、r conditions.(BBC News 3-29-2010)Power plants,heating furnacesautomobiles,trains,planes.volcanic eruptions,sand storm,forest fires industrialization trans-portation natural sourcesAir pollutionrespiratory diseases,lung cancerget killedby destroying their leavesclimate change,acid rainpeopleclimatepl

8、antspesticides（杀虫剂）（杀虫剂）industrial effluent（工业废水）（工业废水）sewage（污水）（污水）fertilizers（化肥）（化肥）oil spill（石油泄漏）（石油泄漏）garbage（垃圾）（垃圾）A newly formed desert near Qinghai Lake because of over pasturing.It was a piece of grassland several years ago.The Yellow RiverWhat to drink?glaciers melting sea level rising

9、（海平面上升）（海平面上升）low countries flooded（低地国家被淹）（低地国家被淹）The 2009 United Nations Climate Change Conference,commonly known as the Copenhagen Summit,was held at Copenhagen,Denmark,between December 7 and 18.According to the Bali Road Map,a framework for climate change mitigation beyond 2012 has been agreed t

10、here.EnvironmentEarth songAir pollutionGlobal warmingWater pollutionCopenhagenAre you ready to change the way you live?The climate crisis can be solved.Here is how:Change your habits to reduce energy for heating and cooling.If you can,buy a hybrid car.When you can,walk or ride a bicycle.Where you ca

11、n,use light rail and mass transit.To Save The EarthTell your parents not to ruin the world that you will live in.If you are a parent,join with your children to save the world that they will live in.Plant trees,lots of trees.Now,lets work together.Stop pollution!内容提要内容提要v本章引言：空气污染源；空气污染对环境以及健康造成的影响；空

12、气污染的解决办法。v本章重点：va.空气污染造成的影响及解决办法vb.科技英语之状语从句的翻译Part I Air Pollutionv空气污染源v空气污染对环境以及人类健康的影响v空气污染的解决办法vQuestions:va.Tell me some patterns of air pollution in different industrial processes.vb.How many conventional devices for control of particulate emissions?v Air pollution can be defined as the prese

13、nce in the outdoor atmosphere of one or more containments in such quantities and of such duration as may be injurious to human,plant,or animal life,or to property,or which may unreasonably interfere with the comfortable enjoyment of life or property,or the conduct of business.Air pollutant sources c

14、an be categorized from several perspectives,including the type of source,their frequency of occurrence and spatial distribution,and the types of emissions.Characterization by source type can be delineated as arising from natural sources or from man-made sources.“Natural sources”include plant pollens

15、,windblown dust,volcanic eruptions,and lighting-generated forest fires.“Man-made sources”can include transportation vehicles,industrial processes,power plants,construction activities,and military training activities.Source characterization according to spatial distribution can be categorized as stat

16、ionary source and mobile sources.Stationary sources are those that have a relatively fixed location.These include point sources,fugitive sources,and area sources.Mobile sources are emitters of air pollutants that move from place to place while yielding emissions.In this text we will mainly talk abou

17、t man-made sources,it is contamination of the air by noxious gases and minute particles of solid and liquid matter(particulates)in concentrations that endanger health.The major sources of air pollution are transportation engines,power and heat generation,industrial processes,and the burning of solid

18、 waste.vAir PollutionvDefinition:Air pollution can be defined as the presence in the outdoor atmosphere of one or more containments in such quantities and of such duration as may be injurious to human,plant,or animal life,or to property,or which may unreasonably interfere with the comfortable enjoym

19、ent of life or property,or the conduct of business.v The major sources of air pollution are transportation engines,power and heat generation,industrial processes,and the burning of solid waste.空气污染空气污染v 空气污染可以定义为室外大气中存在的一种或多种污染物，其含量和持续期可以趋向于伤害人类、植物、动物或财物，或干扰正常生活或商务行为。v 空气污染的主要来源是运输发动机，热电厂，工业生产过程和固体废

20、物焚烧。vSources of air PollutionvThe air pollutants can also be grouped into two categories:primary pollutants and secondary pollutants1.Primary pollutants are those emitted directly into the air.They include particulates,sulfur dioxide,carbon monoxide,nitrogen oxides,and hydrocarbons.Secondary polluta

21、nts are pollutants produced through reactions between primary pollutants and normal atmospheric compounds.For example,ozone forms over urban areas through reactions of primary pollutants,sunlight,and natural atmospheric gases.vThe combustion of gasoline and other hydrocarbon fuels in automobiles,tru

22、cks,and jet airplanes produces several primary pollutants:nitrogen oxides,gaseous hydrocarbons,and carbon monoxide,as well as large quantities of particulates,chiefly lead2.In the presence of sunlight,nitrogen oxides combine with hydrocarbons to form a secondary class of pollutants,the photochemical

23、 oxidants,among them ozone and the eye-stinging peroxyacetylnitrate(PAN).Nitrogen oxides also react with oxygen in the air to form nitrogen dioxide,a foul-smelling brown gas.In urban areas like Los Angeles where transportation is the main cause of air pollution,nitrogen dioxide tints the air,blendin

24、g with other contaminants and the atmospheric water vapor to produce brown smog.Although the use of catalytic converters has reduced smog-producing compounds in motor vehicle exhaust emissions,recent studies have shown that in so doing the converters produce nitrous oxide,which contributes substanti

25、ally to global warming.Sources of air Pollutionv The air pollutants can also be grouped into two categories:primary pollutants(一次污染物)and secondary pollutants(二次污染物).v The combustion of gasoline and other hydrocarbon fuels in automobiles,trucks,and jet airplanes produces several primary pollutants:ni

26、trogen oxides,gaseous hydrocarbons,and carbon monoxide,as well as large quantities of particulates,chiefly lead.v In cities,air may be severely polluted not only by transportation but also by the burning of fossil fuels(oil and coal)in generating stations,factories,office buildings,and homes and by

27、the incineration of garbage.空气污染源v 空气污染物也可以分为两类：一次污染物和二次污染物。v 汽车、卡车、喷气式飞机燃烧汽油和其它碳氢燃料，产生一些主要的污染物质：氧化氮，碳氢化合物，一氧化碳，还有大量的微粒，其主要成分是铅。v 在城市里，空气被严重污染不仅由于交通运输，也由于发电厂、工厂、办公楼、住宅里化石燃料（石油和煤炭）的燃烧以及垃圾焚烧。Definition of primary and secondary pollutants.v Primary pollutants are those emitted(排放)directly into the air.

28、They include particulates,sulfur dioxide,carbon monoxide,nitrogen oxides,and hydrocarbons.v Secondary pollutants are pollutants produced through reactions between primary pollutants and normal atmospheric compounds.For example,ozone forms over urban areas through reactions of primary pollutants,sunl

29、ight,and natural atmospheric gases.一次污染物和二次污染物的定义v“一次污染物”直接释放进入空气。它们包括微粒、二氧化硫、一氧化碳、氮氧化物和碳氢化合物。v“二次污染物”是一次污染物与常见大气化合物反应的产物。例如，城市上空的臭氧是一次污染物、阳光与自然界大气的反应产物。EFFECTS ON HEALTH AND THE ENVIRONMENTv Like photochemical pollutants,sulfur oxides contribute to the incidence of respiratory diseases.Acid rain,a

30、form of precipitation that contains high levels of sulfuric or nitric acids,can contaminate drinking water and vegetation,damage aquatic life,and erode buildings.When a weather condition known as a temperature inversion prevents dispersal of smog,inhabitants of the area,especially children and the e

31、lderly are chronically ill,are warned to stay indoors and avoid physical stress.Even everyday levels of air pollution may insidiously affect health and behavior.Indoor air pollution is a problem in developed countries,where efficient insulation keeps pollutants inside the structure.In less developed

32、 nations,the lack of running water and indoor sanitation can encourage respiratory infections.Carbon monoxide,for example,by driving oxygen out of the bloodstream,causes apathy,fatigue,headache,disorientation,and decreased muscular coordination and visual acuity.Effects on Health and the Environment

33、vEven everyday levels of air pollution may insidiously(潜在的)affect health and behavior.vAir pollution may possibly harm populations in ways so subtle or slow that they have not yet been detected.vA recently discovered result of air pollution are seasonal holes in the ozone layer in the atmosphere abo

34、ve Antarctica and the Arctic,coupled with growing evidence of global ozone depletion(臭氧耗竭).空气污染的影响v 每天空气污染都在不知不觉中影响着我们的健康和行为。v 空气污染很可能以细微缓慢不易察觉的方式危害人类。v 最近发现的空气污染的后果是南北极上空出现季节性的臭氧层空洞，也有越来越多的证据证明全球臭氧消耗。In different countriesv Indoor air pollution is a problem in developed countries,where efficient in

35、sulation keeps pollutants inside the structure.v In less developed nations,the lack of running water and indoor sanitation can encourage respiratory infections.Carbon monoxide,for example,by driving oxygen out of the bloodstream,causes apathy,fatigue,headache,disorientation,and decreased muscular co

36、ordination and visual acuity.不同国家的现状v室内空气污染在发达国家是个问题，高效的隔热系统滞留了室内污染物。v在欠发达国家，自来水和卫生设备的欠缺助长了呼吸道感染。例如一氧化碳，它可以赶走血液中的氧气，使人冷漠，疲劳，头痛，神志不清，肌肉协调性降低，视力下降。vSolutions to Air PollutionvThe conventional devices for control of particulate emissions from industrial sources are cyclones,electrostatic precipitators,

37、fabric filters,and scrubbers.Cyclonic collectors are round conically shaped vessels in which the gas stream enters tangentially and follows a spiral path to the outlet.The spiral motion produces the centrifugal forces that cause the particulate matter to move toward the periphery of the vessel and c

38、ollect on the walls and fall to the bottom of the vessel.Fabric filters,i.e.,baghouses,usually consist of tubular bags made of woven synthetic fabric or fiberglass,in which the dirty gases pass through the fabric while the particulates are collected on the upstream side by the filtering action of th

39、e fabric.The dust retained on the bags periodically shaken off and falls into a collecting hopper for removal.Wet scrubbers use water“sprays”to collect and remove particulates.They may generally be classified as low and high energy scrubbers.Low energy scrubbers of 1 to 6 inches of pressure drop may

40、 consist of simple spray towers,packed towers or impingement plate towers,which find frequently application in incinerators,fertilizer manufacturing,lime kilns,and iron foundries.The high energy scrubber,or Venturi,imparts high velocity to the gas stream by means of converging-diverging dust section

41、,and contacts the stream with injected water.The Venturi scrubber is often used in conjunction with steel furnaces,pulp mills and foundry cupolas.The principal mechanisms of the wet collectors are:1)increasing the size of the particles by combination with liquid droplets thereby increasing their siz

42、e so they may be collected more easily;2)trapping them in liquid film and washing them away.Electrostatic precipitators are particularly suited for gas streams which can be easily ionized and which contain either liquid or solid particulate matter.The operating principle requires three basic steps:1

43、)electrical charging of the suspended particulates;2)collection of the charged particulate matters on a grounded collection surface;3）removal of the particulates from the collecting surface by mechanical scrubbing or flushing with liquids.Solutions to Air Pollutionv The conventional devices for cont

44、rol of particulate emissions from industrial sources are cyclones,electrostatic precipitators,fabric filters,and scrubbers.v We should control air pollution not only from the aspect of technology,but also from the aspect of international laws.v The most satisfactory long-term solutions to air pollut

45、ion may well be the elimination of fossil fuels and the ultimate replacement of the internal-combustion engine.空气污染的解决办法v 用于控制工业污染源颗粒释放的常规装置有旋风除尘器、静电除尘器、布袋除尘器和涤气器。v 人类不仅要在技术方面还要在国际法律方面控制污染。v 最有效的解决空气污染的长远方案就是消除化石燃料的使用并最终替换内燃机。Classification of conventional devicesv Cyclonic collectors are round coni

46、cally shaped vessels in which the gas stream enters tangentially and follows a spiral path to the outlet.The spiral motion produces the centrifugal forces that cause the particulate matter to move toward the periphery of the vessel and collect on the walls and fall to the bottom of the vessel.v Fabr

47、ic filters,i.e.,baghouses,usually consist of tubular bags made of woven synthetic fabric or fiberglass,in which the dirty gases pass through the fabric while the particulates are collected on the upstream side by the filtering action of the fabric.The dust retained on the bags periodically shaken of

48、f and falls into a collecting hopper for removal.v Wet scrubbers use water“sprays”to collect and remove particulates.They may generally be classified as low and high energy scrubbers.常规装置的分类v 旋风集尘器是圆锥形的容器，容器内的气流沿切线方向进入，然后螺旋形路径抵达出口。螺旋运动产生使颗粒物朝容器周边向上运动的离心力，颗粒物聚集于气壁并落到气壁底。v 织物过滤器即袋滤器，通常由机织合成纤维或玻璃纤维制成，含

49、尘气体穿过织物时微粒被拦截收集。截留在袋中的灰尘定期抖落进入收集斗中去除。v 湿式洗涤器使用水雾收集并去除微粒。洗涤器按低能和高能进行分类。Part II Reading MaterialsvText A:Health Effects of NoisevText B:Water pollutionvRequirements of reading materials:(it is arranged by teachers)Part III Translation of EST(12)-状语从句的翻译 英语中的状语从句包括时间状语从句、地点状语从句、原因状语从句、条件状语从句、方式状语从句、目的状

50、语从句、让步状语从句、比较状语从句和结果状语从句等九种。一般来说，英语状语从句相当于汉语偏正复句中的偏句，引导状语从句的连词也大多可以在汉语中找到相应的关联词或表达方式。因此，虽然英语的状语从句形式多样且位置灵活多变，但一般不会给翻译带来很大的困难。科技英语中状语从句的翻译可采用以下方法：v 1、顺译法v 英语大部分状语从句的位置可以放在主句之前，也可以放在主句之后，还可以在主句的主谓语之间。当这些从句位于主句之前时，便于汉语偏正复句语序是一致的，可以按原顺序译出。v 例如：When the width of this size band is very narrow,the soil wil