实用英语U2TextB市公开课一等奖百校联赛特等奖课件.pptx

Pre-Reading TaskPre-Reading Task While-Reading TaskWhile-Reading Task After-Reading Task After-Reading Task Unit 2:Text BUnit 2:Text B第1页Pre-reading TaskPre-reading TaskText-related InformationText-related InformationPre-reading ActivityPre-reading Activity第2页Nuclear PowerNuclear PowerText-related InformationText-related Information第3页Text-related InformationText-related InformationNuclear Power:Nuclear Power:The The energy energy consumed consumed or or produced produced in in modifying modifying the the composition composition of of the the atomic atomic nucleus nucleus and and powering powering electricity-generating electricity-generating plants plants in in countries countries throughout throughout the the world.world.It It is is seen seen by by many many as as the the source source of of inexpensive,inexpensive,clean clean power;power;but but because because of of the the hazardous hazardous radiation radiation emitted emitted in in producing producing that that power power and and the the radioactivity radioactivity of of the the materials materials used,used,others others feel feel that that it it may may not not be be a a viable viable energy energy alternative alternative to to the the use use of fossil fuels or solar energy.of fossil fuels or solar energy.第4页Text-related InformationText-related Information At At present,present,only only the the fission fission process process is is used used in in the the commercial commercial production production of of energy,energy,usually usually to to make make electricity,electricity,but but also also occasionally occasionally to to produce produce steam steam for for district district heating heating or or industrial industrial applications.applications.Public Public opinion opinion remains remains largely largely favourable favourable toward toward nuclear nuclear energy.energy.However,However,questions questions about about the the safety safety and and economy economy of of nuclear nuclear power power have have created created perhaps perhaps the the most most emotional emotional battle battle yet yet fought fought over over energy.energy.Nuclear Nuclear opponents opponents emphasize emphasize a a number number of of unanswered unanswered questions questions about about the the environment,environment,such such as as the the effects effects of of low-level low-level radiation radiation over over long long periods,periods,the the likelihood likelihood of of major major accidents accidents at at a a nuclear nuclear power power plant,plant,and and nuclear powers waste products.nuclear powers waste products.第5页1.What are the advantages and disadvantages of nuclear power?2.From the title of the passage,guess whether the author is for or against theuse of nuclear power.Now read the passage and see if you agree with what the Now read the passage and see if you agree with what the author says.author says.Pre-reading TaskPre-reading TaskExercise 1 Before reading the passage,think over the questions.Exercise 1 Before reading the passage,think over the questions.第6页Text BText BDetailed Study Detailed Study of the Textof the TextWhile-Reading TaskWhile-Reading Task第7页 Text B Text B Nuclear Power:Nuclear Power:Advantages That Outweigh the Risks Advantages That Outweigh the Risks1 1 The views expressed in the The views expressed in the debatedebate on the safety on the safety of nuclear power have come mainly from of nuclear power have come mainly from the interestedthe interestedpartiesparties the United Kingdom Atomic Energy the United Kingdom Atomic Energy Authority and British Nuclear Fuels Limited on the Authority and British Nuclear Fuels Limited on the one hand,and the various one hand,and the various environmental groupsenvironmental groups on on the other.It is not surprising therefore that the publicthe other.It is not surprising therefore that the publicis confused by the many contradictory is confused by the many contradictory statementsstatements,some of which have been sensational.some of which have been sensational.While-Reading TaskWhile-Reading Task第8页 Furthermore,Furthermore,most most of of the the responsible responsible contributions contributions to to the the debate debate have have been been written written in in such such highly highly technical technical terms terms as as to to be be incomprehensible incomprehensible to to the the laylay reader.reader.We We believe believe there there is is a a need need for for an an impartial impartial and and dispassionate dispassionate analysisanalysis of of the the issuesissues involved involved in in language the public can understand.language the public can understand.2 2 While While every every effort effort should should be be made made to to develop develop the the more promising natural sources as quickly as possible,more promising natural sources as quickly as possible,we we believe believe it it will will be be virtually virtually impossible impossible for for any any of of them them to to make make a a significantsignificant contribution contribution to to the the energy energy gap before the beginning of the next century.gap before the beginning of the next century.While-Reading TaskWhile-Reading Task第9页3 3 If If the the world world is is not not to to face face a a substantial substantial fall fall in in living living standards standards with with a a very very real real risk risk of of civil civil upheaval upheaval if if not not war war there there is is no no alternative alternative but but to to rely rely on on a a major major contribution contribution of of energy energy from from nuclear nuclear sources.sources.However,However,as as it it is is,there there are are genuine genuine anxieties anxieties which which must must be be answered answered objectively.objectively.These These fall fall under under the the following following broad headings:broad headings:(I)(I)The The long-term long-term effects effects of of the the low low level level radiation radiation to to which which workers workers in in the the plants plants and and the the public public may may be be exposedexposed;(II)(II)the the possibility possibility of of a a“run“run away”away”leading leading to to an an atomic atomic explosion;explosion;(III)the disposal of radioactive waste.(III)the disposal of radioactive waste.While-Reading TaskWhile-Reading Task第10页4 4 We will deal with these We will deal with these in turnin turn.5 5 1 1 Acceptable Acceptable limits limits of of radiation:radiation:The The long-term long-term effect effect of of low low doses doses of of radiation radiation is is a a particularly particularly difficult difficult subject subject since since medical medical experts experts disagree disagree on on the the interpretation of such statistical evidence as is interpretation of such statistical evidence as is availableavailable.However,However,two two facts facts emergeemerge which which seem seem to to us us significant:significant:(a)(a)there there is is no no evidence evidence that that the the incidence incidence of of cancer cancer or or other other diseases diseases among among the the work-force work-force of of the the United United Kingdom Kingdom nuclear nuclear plants plants is is higher higher than than the the national national average.average.(b)(b)the the average average exposure exposure of of the the public public to to radiation radiation as as a a result result of of nuclear nuclear power power is is only only a a minute minute fraction fraction(0.2(0.2 per per cent)cent)of of the the radiation radiation from from other other sources sources mainly natural.mainly natural.While-Reading TaskWhile-Reading Task第11页6 6 2 2 The The worst worst conceivable conceivable accident:accident:It It must must be be accepted accepted that that no no process process or or mechanism mechanism can can be be 100 100 per per cent cent safe.safe.However,However,under under no no circumstancescircumstances could could a a thermal thermal power power reactor reactor of of any any type type explode explode like like an an atomic atomic bomb.bomb.The The worst worst that that could could happen happen in in the the improbable improbable event event ofof a a whole whole series series of of unlikely unlikely incidents incidents happening happening together,together,would would be be an an escape escape of of radioactivity radioactivity to to the the surrounding atmosphere.surrounding atmosphere.7 7 It It has has been been calculatedcalculated by by Professor Professor Rasmussen,Rasmussen,of of the the Massachusetts Massachusetts Institute Institute of of Technology,Technology,that that the the chances chances of of such such an an accident accident causing causing 100 100 deaths deaths for for a a group group of of 100 100 power plants would be one incident in 100 000 years.power plants would be one incident in 100 000 years.While-Reading TaskWhile-Reading Task第12页While-Reading TaskWhile-Reading Task8 8 3 3 The The disposal disposal of of radioactive radioactive waste.waste.The The spent spent fuel fuel elements elements from from any any reactor reactor are are highly highly radioactive radioactive and and contain contain fission fission and and other other products products with with half half lives lives ranging fromranging from a few seconds to many thousands of years.a few seconds to many thousands of years.9 9 It It should should be be realized,realized,however,however,that that the the radiation radiation(of(of whatever whatever sort)sort)emitted emitted by by a a particular particular element element is is caused caused by by the the process process of of its its radioactive radioactive decay.decay.The The elements elements with with a a high high rate rate of of decay decay(short(short half half lives)lives)therefore therefore emit emit very very intenseintense radiation,radiation,while while those those with with low low rates rates of of decay(long half lives)emit only low levels.decay(long half lives)emit only low levels.第13页10 10 After After chemical chemical separation,separation,some some of of the the elements elements(uranium(uranium and and plutonium)plutonium)are are recycled recycled for for further further use;use;the the remainder remainder have have to to be be stored stored or or disposed disposed of of in in some some way.way.The The highly highly active active concentrated concentrated wastes wastes in in liquid liquid form form are are at at present present stored stored in in stainless stainless steel steel double-double-walled walled tanks tanks for for additionaladditional safety.safety.There There would would be be obvious obvious advantages advantages from from the the point point of of view view of of long-term long-term storage storage if if the the concentrates concentrates could could be be converted converted toto a a solid,solid,and and a a process process has has been been worked worked out out for for turning turning them them into an insoluble glass.into an insoluble glass.While-Reading TaskWhile-Reading Task第14页1111 There There are are areas areas in in the the earths earths crust crust where where the the natural natural levels levels of of radioactivity radioactivity are are already already high,high,and and as as in in so so many many other other instances,instances,the the additional additional radiation radiation due due to to mans mans efforts efforts would would be be insignificant insignificant compared compared with natural sources.with natural sources.While-Reading TaskWhile-Reading Task第15页 Nuclear Power:More Advantages Than Risks Nuclear Power:More Advantages Than RisksNuclear Power:Advantages That Outweigh the RisksNuclear Power:Advantages That Outweigh the Risks第16页 The different opinions which come from a The different opinions which come from a discussion on the safety of nuclear power.discussion on the safety of nuclear power.The views expressed in the debate on the safety of The views expressed in the debate on the safety of nuclear power have come mainly from the interested nuclear power have come mainly from the interested parties.and the various environmental groups on parties.and the various environmental groups on the other.the other.第17页e.g.e.g.The topic aroused an interesting The topic aroused an interesting debatedebate.Truth develops through Truth develops through debatedebate between different between different views.views.debate:debate:n.n.a public meeting in which a question is a public meeting in which a question is talked talked over over by by at at least least 2 2 people people or or groups,groups,each expressing a different point of view;each expressing a different point of view;argument or discussion in general argument or discussion in general第18页e.g.e.g.There is urgent need to There is urgent need to debatedebate this issue openly.this issue openly.The subject was hotly The subject was hotly debateddebated.cf.cf.debate:debate:v.v.to argue about(something)in an to argue about(something)in an effort to persuade other people effort to persuade other people第19页the groups that are directly concerned with the groups that are directly concerned with the issue and are likely to be affected by its the issue and are likely to be affected by its resultsresultsthe interested parties:the interested parties:第20页groups who are concerned with the protection groups who are concerned with the protection of the environment from pollution,etc.of the environment from pollution,etc.the environmental groups:the environmental groups:第21页 So So it it is is not not surprising surprising that that the the public public doesnt doesnt know know who who is is right right because because many many views views in in the the debate debate are are contradictory contradictory and and some some of of them them have have been shocking.been shocking.It It is is not not surprising surprising therefore therefore that that the the public public is is confused confused by by the the many many contradictory contradictory statements,statements,some of which have been sensational.some of which have been sensational.第22页e.g.e.g.The details of the agreement need more exact The details of the agreement need more exact statementstatement.We need further facts to back up our We need further facts to back up our statementsstatements.statement:statement:n.n.1)an expression in words1)an expression in words第23页e.g.e.g.Do you believe the witnesss Do you believe the witnesss statementstatement?The educational authorities gave out the The educational authorities gave out the following following statementstatement.statement:statement:n.n.2)a written or spoken declaration,2)a written or spoken declaration,esp.of a formal kind esp.of a formal kind第24页 .most most of of the the sensible sensible and and reliable reliable articles articles for for the the debate debate have have been been written written in in such such highly highly technical technical terms terms that that the the non-professional