Гвоздева Пхысицс фор адванцед студентс 2011

–And besides the opportunities in medicine? What else?

–Molecular manufacturing will let us have a much lower cost infrastructure. In other words, today manufacturing takes place in very large facilities. If you want to build, for example, a computer chip, you need a giant semiconductor fabrication facility. But nature can grow complex molecular machines using nothing more than a plant. Potatoes are a miracle of biology, and yet they are so cheap. The reason for this is that the potato can grow more potatoes. It is a self-replicating technology and it demonstrates the feasibility of a self-replicating manufacturing capability.

–Are there any other areas that would be significantly affected by nanotechnology?

–Nanotechnology will let us build incredibly powerful molecular

computers. Computer storage and operation capacity will be improved by a factor of a million. Lighter computers and lighter sensors would let us have more function in a given weight, which is very important if you are launching things into space. Besides, we will have much lighter, much stronger materials, and this will reduce the cost of planes and rockets.

–How will artificial systems be different from living systems?

–They will function correctly if we provide them with a very specif-

ic environment. Without that environment they won’t function.

–Can you put any kind of timeframe on that?

–We’re talking about decades – and, probably, not many decades.

Vocabulary Notes

1.to address a problem – to deal with a problem

2.an opportunity – a possibility

3.a root – (here) an origin

4.facilities – equipment

5.a feasibility – a possibility

6.a capability – ability

7.to replicate − to make an exact copy

Exercise 4 (in pairs)

Summarize the answer to each question in one sentence, write the sentences down and reproduce the dialogue formulated by you.

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V. We use would to talk about the natural course and behavior of things and events as a result of some action. Would is the less definite form of will

Study the sentence.

Pushing the control rod deeper into the reactor would reduce its power output, and its extracting would increase it.

VI. You translate a past participle V3 before you translate a N. We sometimes put V3 before a noun, but we usually put it after a

noun.

Study the sentences.

1.Commonly used moderators include regular (light) water (75% of the world’s reactors).

2.The number of particles emitted decreased.

3.The energy released is in the order of one electron volt per atom.

4.Fossil fuels, such as oil, gas and coal, are simply stored solar ener-

gy.

VII. that (those) is used to refer to a thing (things) that has been mentioned before.

Study the sentences.

The heat power generated by the nuclear reaction is 1,000,000 times that of the equal amount of coal.

VIII. Saying what will happen we use going to (not will) when there is something in the present situation which shows what will happen. The speaker feels sure about what will happen because of the situation now.

Study the sentence.

Mankind is going to need vast amounts of energy in the future.

Give Russian correspondence:

as opposed to (unlike), to turn into (to change into), original (initial), and so on (etc.), thereby (thus, as a result), commonly (typically), to result in (to lead to, to give rise to), a time, then (after that), former, so (therefore), in addition to (besides), considerable (rather large), factor (coefficient), by, somewhat (a bit), the only (single)

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THE NUCLEAR REACTOR

Study the passage. Mind the underlined grammar points. Translate the sentences marked with asterisks in writing.

A nuclear reactor is a device in which nuclear chain reactions are initiated, controlled, and sustained at a steady rate, as opposed to a nuclear bomb, in which the chain reaction occurs in a fraction of a second and is uncontrolled causing an explosion.

The nuclear reactor is used as an energy source for the generation of electric power. This energy is used to heat water and turn it into steam. The steam is used to drive a turbine connected to a generator which produces electricity.

The reactor converts nuclear energy into heat. When a relatively large fissile atomic nucleus (usually uranium-235 or plutonium-239) absorbs a neutron it undergoes nuclear fission. The original heavy nucleus splits into two or more lighter nuclei which release kinetic energy, gamma radiation and free neutrons; collectively known as fission products. A portion of these products is later absorbed by other fissile atoms and trigger further fission events, which release more neutrons, and so on.

*The nuclear chain reaction can be controlled by neutron moderators to change the portion of neutrons to cause more fission. In nuclear engineering, a neutron moderator is a medium which reduces the velocity of fast neutrons, thereby turning them into thermal neutrons capable of sustaining a nuclear chain reaction involving uranium-235*. Commonly used moderators include regular (light) water (75% of the world’s reactors), solid graphite (20% of reactors) and heavy water (5% of reactors). The increase or decrease of the rate of fission will result in the increase or decrease of the energy output.

*The reactor core generates heat by converting the kinetic energy of fission products into thermal energy. The heat power generated by the nuclear reaction is 1,000,000 times that of the equal amount of coal.*

A cooling source – often water but sometimes a liquid metal – is circulated past the reactor core to absorb the heat that it generates. The heat is carried away from the reactor and is then used to generate steam.

The power output of the reactor is controlled by controlling the number of neutrons able to create more fission. Control rods are used to absorb neutrons. Pushing the control rod deeper into the reactor would reduce its power output, and its extracting would increase it.

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Nuclear reactors generally have automatic and manual systems to insert large amounts of boron into the reactor to shut down the fission reaction in case of emergency.

Fuel removed from a reactor, after it has reached the end of its useful life, can be reprocessed to produce new fuel.

Vocabulary Notes

1.regular – ordinary

2.the reactor core – the active zone of the reactor

3.the power output – the amount of energy produced

4.a control rod – a thin long straight bar made of graphite

5.to remove – to take out

POST-READING TASK

(To be done at home in writing)

I. What is the difference between a nuclear reactor and a nuclear bomb?

II. Answer the questions.

1.When does nuclear fission occur?

2.What is a fission event?

3.What are fission products?

4.What is the function of a neutron moderator?

5.What is a neutron moderator?

6.What does the energy output of a reactor depend on?

7.Which is more efficient: a coal plant or a reactor plant?

8.What is the function of a cooling source?

9.How is a nuclear chain reaction controlled?

10.What is the function of control rods?

11.How is a fission reaction shut down in case of emergency?

III. Make up 4 short sentences with the below expressions to describe a chain reaction.

1.to undergo nuclear fission

2.to split into

3.to release kinetic energy

4.to trigger further fission events

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--.Human activity over the last two hundred years has raised levels of greenhouse gases leading to more radiation absorption and re-radiation. It’s as if the Earth is now covered with a thick blanket which is causing it to overheat. We really shouldn’t underestimate the threat this poses. Carbon dioxide levels have increased 31% since 1750. Methane is the second biggest contributor to the greenhouse effect. Its share of the effect is about a fifth.

--What human activities cause enhanced greenhouse effect?

-- Agriculture and energy production accounts for about 60% of methane emissions. Methane’s GWP or global warming potential is twenty one. GWP takes into account factors such as potency as well as lifetime in the atmosphere.

INTERVIEW WITH CHARLES HILL

“Mankind is going to need a vast amount of energy in the future”

Dr Charles Hill, nuclear physicist and former lab director at Argonne National Laboratory

Read the interview in pairs twice, changing parts.

--What is, in your opinion, the most efficient and less polluting source of energy, capable to supply the power demand of the future?

--There is only one. It’s coal. It’s natural gas. Some limited addi-

tional use of the more exotic forms of energy, like solar and wind. But they are limited in what they can do. So it is going to be fossil fuel. The question immediately arises, well, how long will it last? And everyone has a different opinion on that. One thing that is certain is that the increase in the use of fossil fuels will sharply increase the amount of carbon dioxide in the atmosphere. Another thing is certain. You will put a lot more pollutants into the atmosphere in addition to carbon dioxide. One can point to natural gas. Well, natural gas has fewer pollutants, and it gives some considerable factor of perhaps two - more energy for the amount of carbon dioxide put into the air than does coal. But if you are increasing the amount of fossil fuels by a large number, like five, then the use of natural gas is not a long - term solution. It simply somewhat reduces what may be a very serious problem.

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--What do you think about solar energy?

--Solar? No.

--Wind?

--No, small amounts only. The simplest form of pencil calculation will tell you that. The only way you can produce the vast amount of energy to supply the demand of mankind is with sources of energy, where the energy is concentrated. With solar energy the main problem is gathering it. In a nuclear form of energy, it is there. It has been gathered.

--Which puts more radiation into the atmosphere: a coal plant or a nuclear plant?

--Coal plants, by large margins.

--Where is the radiation from?

--The radiation is from the contaminants in the coal - thorium, uranium. It’s a large source of pollution.

Give your comments in writing. Follow the interview.

1.Solar and wind energy are limited in what they can do. (What are they limited in?)

2.Everybody has a different opinion on that. (On what?)

3.One can argue whether there is a greenhouse effect.. (What do you think?)

4.Natural gas gives a considerable factor of perhaps two. (What fac-

tor does he mean?)

5.The simplest form of pencil calculation will tell you that.

(What?)

6.With solar energy the main problem is gathering it. (How is solar

energy gathered?)

7. A coal plant puts more radiation into the atmosphere than a nuclear plant. (Why?)

SHOULD NUCLEAR POWER BE THE FUEL OF CHOICE?

Analyze the information, write an outline and be ready to speak either as an advocate or an opponent of the nuclear power.

Absolutely, says Tony Blair. Nuclear power must stay on the agenda if you are serious about the issue of climate change. Definitely, says the independent scientist James Lovelock, civilization is in danger from

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global warming and must use nuclear power - the one safe, available energy source.

Electricity generation is responsible for about one third of worldwide greenhouse gases. Nuclear power, which provides 16% of the world’s electricity, saves roughly 600m tones of carbon emissions per year.

On emissions, nuclear compares with renewables. The nuclear power chain, from uranium mining to waste disposal emits roughly 2-6 grams of carbon per kilowatt-hour. This is about the same as wind and solar power, and two orders of magnitude below coal, oil and even natural gas.

With world electricity demand expected to increase up to 100% by 2020, the Nuclear World Association says nuclear is now not just an option but a necessity for survival. With carbon emissions threatening the very stability of the biosphere, the security of our world requires a massive transformation to clean energy.

There are, however, many obstacles standing in the way of a nuclear renaissance. A global nuclear programme could cost hundreds of billions of dollars to get up and running and has little likelihood of attracting private finance. Nuclear stations usually take 8 to 15 years to build, and almost that long to start repaying their financial and carbon investments. “Renewables and energy conservation can deliver the cuts immediately,” says a Greenpeace spokesman. To start a new nuclear programme would divert political will and money away from renewables, which are proven. The money which would have to be spent developing a new generation of nuclear stations could massively stimulate other forms of renewables.

Adapted from The Guardian

GLOBAL WARMING AND CLIMATE CHANGE

IS NUCLEAR POWER ABOUT TO HAVE ITS RENAISSANCE?

Nuclear power is the only practical way of countering climate change, oil shocks and landscape destruction in the West

The Guardian

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