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1、Pre-Reading Task While-Reading Task After-Reading Task,Unit 2: Text B,Pre-reading Task,Text-related Information Pre-reading Activity,Nuclear Power,Text-related Information,Text-related Information,Nuclear Power:,The energy consumed or produced in modifying the composition of the atomic nucleus and p
2、owering electricity-generating plants in countries throughout the world. It is seen by many as the source of inexpensive, clean power; but because of the hazardous radiation emitted in producing that power and the radioactivity of the materials used, others feel that it may not be a viable energy al
3、ternative to the use of fossil fuels or solar energy.,Text-related Information,At present, only the fission process is used in the commercial production of energy, usually to make electricity, but also occasionally to produce steam for district heating or industrial applications. Public opinion rema
4、ins largely favourable toward nuclear energy. However, questions about the safety and economy of nuclear power have created perhaps the most emotional battle yet fought over energy. Nuclear opponents emphasize a number of unanswered questions about the environment, such as the effects of low-level r
5、adiation over long periods, the likelihood of major accidents at a nuclear power plant, and nuclear powers waste products.,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
6、 passage and see if you agree with what the author says.,Pre-reading Task,Exercise 1 Before reading the passage, think over the questions.,Text B Detailed Study of the Text,While-Reading Task,Text B Nuclear Power: Advantages That Outweigh the Risks 1 The views expressed in the debate on the safety o
7、f nuclear power have come mainly from the interested parties the United Kingdom Atomic Energy Authority and British Nuclear Fuels Limited on the one hand, and the various environmental groups on the other. It is not surprising therefore that the public is confused by the many contradictory statement
8、s, some of which have been sensational.,While-Reading Task,Furthermore, most of the responsible contributions to the debate have been written in such highly technical terms as to be incomprehensible to the lay reader. We believe there is a need for an impartial and dispassionate analysis of the issu
9、es involved in language the public can understand. 2 While every effort should be made to develop the more promising natural sources as quickly as possible, we believe it will be virtually impossible for any of them to make a significant contribution to the energy gap before the beginning of the nex
10、t century.,While-Reading Task,3 If the world is not to face a substantial fall in living standards with a very real risk of civil upheaval if not war there is no alternative but to rely on a major contribution of energy from nuclear sources. However, as it is, there are genuine anxieties which must
11、be answered objectively. These fall under the following broad headings: (I) The long-term effects of the low level radiation to which workers in the plants and the public may be exposed; (II) the possibility of a “run away” leading to an atomic explosion; (III) the disposal of radioactive waste.,Whi
12、le-Reading Task,4 We will deal with these in turn. 5 1 Acceptable limits of radiation: The long-term effect of low doses of radiation is a particularly difficult subject since medical experts disagree on the interpretation of such statistical evidence as is available. However, two facts emerge which
13、 seem to us significant: (a) there is no evidence that the incidence of cancer or other diseases among the work-force of the United Kingdom nuclear plants is higher than the national average. (b) the average exposure of the public to radiation as a result of nuclear power is only a minute fraction (
14、0.2 per cent) of the radiation from other sources mainly natural.,While-Reading Task,6 2 The worst conceivable accident: It must be accepted that no process or mechanism can be 100 per cent safe. However, under no circumstances could a thermal power reactor of any type explode like an atomic bomb. T
15、he worst that could happen in the improbable event of a whole series of unlikely incidents happening together, would be an escape of radioactivity to the surrounding atmosphere. 7 It has been calculated by Professor Rasmussen, of the Massachusetts Institute of Technology, that the chances of such an
16、 accident causing 100 deaths for a group of 100 power plants would be one incident in 100 000 years.,While-Reading Task,While-Reading Task,8 3 The disposal of radioactive waste. The spent fuel elements from any reactor are highly radioactive and contain fission and other products with half lives ran
17、ging from a few seconds to many thousands of years. 9 It should be realized, however, that the radiation (of whatever sort) emitted by a particular element is caused by the process of its radioactive decay. The elements with a high rate of decay (short half lives) therefore emit very intense radiati
18、on, while those with low rates of decay (long half lives) emit only low levels.,10 After chemical separation, some of the elements (uranium and plutonium) are recycled for further use; the remainder have to be stored or disposed of in some way. The highly active concentrated wastes in liquid form ar
19、e at present stored in stainless steel double-walled tanks for additional safety. There would be obvious advantages from the point of view of long-term storage if the concentrates could be converted to a solid, and a process has been worked out for turning them into an insoluble glass.,While-Reading
20、 Task,11 There are areas in the earths crust where the natural levels of radioactivity are already high, and as in so many other instances, the additional radiation due to mans efforts would be insignificant compared with natural sources.,While-Reading Task, Nuclear Power: More Advantages Than Risks
21、,Nuclear Power: Advantages That Outweigh the Risks, The different opinions which come from a discussion on the safety of nuclear power .,The views expressed in the debate on the safety of nuclear power have come mainly from the interested parties . and the various environmental groups on the other.,
22、e.g. The topic aroused an interesting debate. Truth develops through debate between different views.,debate: n. a public meeting in which a question is talked over by at least 2 people or groups, each expressing a different point of view; argument or discussion in general,e.g. There is urgent need t
23、o debate this issue openly. The subject was hotly debated.,cf. debate : v. to argue about (something) in an effort to persuade other people,the groups that are directly concerned with the issue and are likely to be affected by its results,the interested parties:,groups who are concerned with the pro
24、tection of the environment from pollution, etc.,the environmental groups:, So it is not surprising that the public doesnt know who is right because many views in the debate are contradictory and some of them have been shocking.,It is not surprising therefore that the public is confused by the many c
25、ontradictory statements, some of which have been sensational.,e.g. The details of the agreement need more exact statement. We need further facts to back up our statements.,statement: n . 1 ) an expression in words,e.g. Do you believe the witnesss statement? The educational authorities gave out the f
26、ollowing statement.,statement: n . 2) a written or spoken declaration, esp. of a formal kind, . most of the sensible and reliable articles for the debate have been written in such highly technical terms that the non-professional reader can not understand them.,. most of the responsible contributions
27、 to the debate have been written in such highly technical terms as to be incomprehensible to the lay reader.,e.g. lay opinion (外行意见) to the lay mind (对外行人来说),lay: v. not trained in or having knowledge of a particular profession or branch of learning, such as law or medicine, We believe that it is ne
28、cessary to have a fair and objective explanation of the problems concerned using no complicated technical language that the public cant understand.,We believe there is a need for an impartial and dispassionate analysis of the issues involved in language the public can understand.,e.g. The FBI wants
29、a complete analysis of how the crime was committed. On analysis, it gave the following results.,analysis: n. an examination of something together with thoughts and judgments about it,e.g. That issue must be decided before any other questions can be dealt with. Whether I go there or not is a debatabl
30、e issue.,issue: n. 1) a question that arises for discussion,e.g. The motor vehicle department handles the issue of driving licences. The issue of water from the cracked pipe grew so serious that we called the dire department.,issue: n. 2) the act of coming out,e.g. Have you read todays issue of “The
31、 Times”? The last issue of our weekly paper consisted of 1 000 copies.,issue: n. 3) something printed, . we believe it will be almost impossible for any of them to help to fill to an important degree the energy gap .,. we believe it will be virtually impossible for any of them to make a significant
32、contribution to the energy gap .,e.g. Penicillin was an extremely significant medical discovery. Does the report give all the significant facts of the case?,significant: a. of noticeable importance or effect, . the only type of energy we can rely on is from nuclear sources.,. there is no alternative
33、 but to rely on a major contribution of energy from nuclear sources., But, in fact, there are real worries .,However, as it is, there are genuine anxieties .,e.g. I thought things would get better, but as it is they are getting worse. As it is, we can hardly get to the airport by 5 oclock.,as it is:
34、 in reality; according to the situation that actually exists, esp. when that situation is different from what one expected or need,e.g. In many ways children live, as it were, in a different world from adults.,cf. as it were: as it might be said to be; as if it really were; seemingly (used to indica
35、te that the speaker is giving her or his own impression of a situation and may not be using words in their exact sense),e.g. The small craft was exposed to the dangers of the open sea. It can not be exposed to the sun. cf. He believes in regularly exposing his pupils to great works of art.,be expose
36、d to: to be left without protection (from something), We will explain these one by one in details.,We will deal with these in turn.,e.g. All the students recited the poem in turn. Each man in turn got up and spoke.,in turn: successively; in order, . because medical experts have their own explanation
37、 of the existing statistical evidence / have different opinions about the explanation of the statistical evidence that can be obtained now.,. since medical experts disagree on the interpretation of such statistical evidence as is available.,e.g. These data are readily available. Is the president ava
38、ilable for the graduation ceremony tomorrow?,available: a. able to be got, obtained, used, seen, etc., However there are two facts which seem important to us: .,However, two facts emerge which seem to us significant: .,e.g. The sun emerged from behind the clouds. Many facts emerged as a result of th
39、e investigation.,emerge: v. to come or appear; become known, However, it is absolutely impossible that any type of thermal power reactor could explode like an atomic bomb.,However, under no circumstances could a thermal power reactor of any type explode like an atomic bomb.,e.g. Under no circumstanc
40、es are you to leave the house.,under / in no circumstances: never; regardless of events (used to emphasize that something must definitely not happen),e.g. Under the circumstances, there was nothing I could say.,cf. under / in the circumstances: because of the conditions; because things are as they a
41、re (used to say that a particular situation makes an action, decision, etc. necessary or acceptable when it would not normally be),e.g. Under any circumstances a gentleman has no right to hurt a woman.,under / in any circumstances: in any case, The worst thing that could happen if a whole series of
42、unlikely incidents happened together, .,The worst that could happen in the improbable event of a whole series of unlikely incidents happening together, .,e.g. In the unlikely event of an accident, contact us at this number,in the event of: (formal) if something happen,e.g. Did she calculate the cost
43、? Yes, she calculated that it would cost $100. The scientist could not calculate when the spaceship would reach the moon.,calculate: v. to estimate; find out by working with numbers,the half life of a radioactive substance is the length of time it takes to lose half of its radioactivity,half(-)life:
44、,e.g. Those dresses range in price from eighteen to fifty dollars. His lectures ranged from music to mathematics.,range from . to: to vary (between limits),e.g. The patient has an intense will to recover. The heat from the furnace is intense.,intense: a. strong (in quality or feeling), After chemica
45、l treatment, .,After chemical separation, ., The concentrated wastes in liquid form with high level of radiation are now kept in stainless steel double-walled tanks for more safety.,The highly active concentrated wastes in liquid form are at present stored in stainless steel double-walled tanks for
46、additional safety.,e.g. The charge for the delivery of the furniture is additional. That is an additional reason for not leaving.,additional: a. extra; added,e.g. Coal can be converted to gas by burning. The sofa can be converted into a bed at night.,convert . to / into: to cause to change to or int
47、o another form, substance, or state, or from one use or purpose to another,After-Reading Task,Outline Reading Comprehension Vocabulary and Structure,Outline,After-Reading Task,Nuclear power an issue in the debate: a. an impartial and dispassionate analysis required; b. an impossible contribution by
48、any other natural resources to the energy gap.,Outline,After-Reading Task,Nuclear power a promising energy alternative: a. no option but the nuclear power that counts; b. questions raised concerning the nuclear power: 1) the long-term effects of the low level radiation 2) the “run away” leading to a
49、n atomic explosion 3) the disposal of radioactive waste c. answers to the questions (To each of the questions, a negative answer has been given by the author together with many figure and facts.),Exercise 2 Decide whether the statements are True (T) or False (F) according the passage.,Reading Comprehension,1. On the safety of nuclear power, the views expressed by the environmental groups are quite different f