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Better metals are vital to technological progress



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1. Since the earliest days the preparation of metals for mechanical use was vital to the advance of civilization. Gold, silver and copper were the first to be used by a primitive man, as they were found free in nature. Today we know more than sixty-five metals available in large enough quantities to be used in industry.

2. Metals are mostly solid at ordinary temperature and possess comparatively high melting points with the exception of mercury. They are for the most part1 good conductors of heat and electricity, and silver is the best in this respect2. As to3 their chemical properties the first point to be mentioned is that they vary widely in degree of chemical activity: some are enormously active and others are inert. The Earth contains a large number of metals useful to man. Of all metals to be utilized in industry iron remains by far4 the most important. Modern industry needs considerable quantities of this metal either in the form of iron or steel.

3. To get the desirable characteristics in metals or to improve them the art to mix metals and other substances began to develop. The first alloys that were formed in this way were sometimes stronger, tougher, harder and more elastic than the metals of which they were composed. To estimate nowadays how many alloys there exist in the modern world is difficult because their numbers increase daily.

4. To serve special uses modern metals and alloys must be lighter yet stronger, more corrosion-resistant, more suitable for automated fabrication yet less expensive than those available before.

5. Today transformation, communication, construction, farming and manufacturing all depend on the availability of suitable metals and alloys.

 

VII. Прочитайте 1 и 2-й абзацы текста и ответьте на вопросы письменно.

1.What was vital to the advance of civilization?

2.What metals were the first to be used by a man?

3.Why were they used first?

4.How many metals are available in large quantities today?

5.What do transportation, communication, construction and manufacturing depend on?

Вариант 2

I. Перепишите следующие предложения, определите в каждом из них видовременную форму и залог глагола-сказуемого (см. образец). Переведите предложения на русский язык.

1. When much had been done in the study of ecology by our institute it became an important scientific center.

2. This material is unaffected by solar radiation.

3. During the experiment the air in the laboratory was being purified by two ventilators.

4. Great deposits of coal have been discovered in our region.

 

II. Перепишите следующие предложения и переведите их на русский язык, обращая внимание на разные значения слов it, that, one.

1.It is necessary to find new sources of cheap energy.

2.It was Einstein who came to the conclusion that the electromagnetic field is influenced by the gravitational field.

3. This metro station was opened last year and that one will be put into operation in two years.

 

III. Перепишите предложения и переведите их на русский язык, обращая внимание на различные значения глаголов to be, to have, to do.

1.Man had to learn to obtain electric power directly from the Sun.

2.At present most of the industrial enterprises have their own electric power stations.

3.Specialists do not use solar cells in industry as they are too expensive.

4.The engineers are to study the problem of using cosmic rays.

 

IV. Перепишите следующие предложения и переведите их на русский язык, обращая внимание на бессоюзное подчинение.

1. The methods we have just described are very effective.

2. The instruments our plant produces help to automate production processes.

 

V. Перепишите следующие предложения и переведите их на русский язык, обращая внимание на функцию инфинитива.

1.We hope to get new data in a week or two.

2.A number of devices were developed to detect cosmic rays.

3.He spoke about the fuels to be utilized in space research.

4.To operate new flexible line became possible thanks to computers.

 

VI. Прочитайте и переведите с 1 по 3-й абзацы текста. Перепишите и письменно переведите 2 и 3-й абзацы.

Пояснения к тексту:

1.magneto – heat engine – магнитно-тепловой двигатель

2.inexhaustible – неисчерпаемый, неистощимый.

 

Sun-driven engine

1. It is common knowledge that certain metals and their alloys are attracted by a magnet. After heating, this property vanishes; it is restored after cooling down. A new magneto-heat engine1 works on this principle. This invention relates to devices which transform thermal power, for instance, the power of the sun rays, into a mechanical power of rotation.

2. We know solar power is inexhaustible2 and its use does not harm the environment. That’s why such importance is attached to devices which make it possible to apply the idea of direct use of solar power, transforming it into mechanical forms of power. The development of an engine directly driven by a heat source such as solar power, makes it possible to simplify and make power generation considerably cheaper, in comparison to the existing thermal engines we use today.

3. The rotor of the new engine is made of an alloy that loses its magnetic properties at 100oC. If the rotor is heated on one side, the cold side of the rotor will turn toward the magnet. Since heating continues, the rotor goes on rotating too. Thus solar power can be used as a source of heat in this case. The magneto-heat engine can drive pumps in waterless districts, it can also be widely used for watering greenery in cities and settlements.

4. By using thermo-magnetic alloys it is possible to develop a lot of automatic devices, for example, solar clocks, thermometers, etc. Mention should be made that these devices can withstand extreme temperatures. To organize the production of the necessary alloys is simple as there is no need for rare materials or complex technology.

 

VII. Прочитайте 1 и 2-й абзацы текста и ответьте на вопросы письменно.

1.What property do many metals and their alloys possess?

2.Where are magneto- heat engines used?

3.Where are thermo-magnetic alloys used?

4.What temperatures can these devices withstand?

5.Is it simple or difficult to produce such alloys?

 

Вариант 3

I. Перепишите следующие предложения, определите в каждом из них видовременную форму и залог глагола-сказуемого (см. образец). Переведите предложения на русский язык.

1.The radar has been used for the automatic control of ground transport.

2.Today plastics are being widely used instead of metals.

3.The construction of the dam has been completed this month.

4.The alloys were experimented upon in our lab.

 

II. Перепишите следующие предложения и переведите их на русский язык, обращая внимание на разные значения слов it, that, one.

1.It is the number of electrons within the atom that determines the properties of a substance.

2.The territory of Moscow is larger than that of London.

3.In London one must get used to the left-side traffic.

 

III. Перепишите предложения и переведите их на русский язык, обращая внимание на различные значения глаголов to be, to have, to do.

1.Some substances do not conduct heat

2.These computers will have to perform millions of operations per second.

3.He was asked to make a report.

4.You are to present the results of your research in a week.

 

IV. Перепишите следующие предложения и переведите их на русский язык, обращая внимание на бессоюзное подчинение.

1.I think he has made a mistake in his calculations.

2.The heat a body contains is the kinetic energy of its molecules.

 

V. Перепишите следующие предложения и переведите их на русский язык, обращая внимание на функцию инфинитива.

1.They promised to supply us with the necessary equipment.

2.The experiment to be carried out is of great importance for our research.

3.To convert chemical energy into electrical energy we must use an electrical cell.

4.The task of the computer is to operate flexible line properly.

 

VI. Прочитайте и переведите с 1 по 4-й абзацы текста. Перепишите и письменно переведите 1 и 2-й абзацы.

Пояснения к тексту:

1.self-taught engineer – инженер самоучка

2.crossing – переправа

3.a span – пролёт, to span – перекрывать

 

On bridge building

1. The history of Russian bridge building is closely connected with the name of Kulibin, one of the most talented self-taught engineers1. From his early childhood Kulibin showed a keen interest in all kinds of mechanical devices. To acquire skill and knowledge became the boy’s greatest desire. But books were difficult to obtain in the provincial town where he lived and there was no one to instruct him in mechanics. The difficulties which he had to overcome seemed irresistible. But in spite of all that he succeeded in going to Petersburg where he was appointed mechanic to the Academy of sciences and since then spent all his free time and all his money on new inventions.

2. In Petersburg Kulibin undertook a very difficult engineering problem – to design a bridge across the Neva as there was not a single permanent bridge in this city to provide a crossing2 at any season of the year. Kulibin was the first to think of spanning3 the river with an arched bridge. According to his plan the bridge was to have a single span to leave a free water way for ships and barges. It was a daring idea: arched bridges of similar construction had been built before but no engineer dared even to think of constructing a bridge with a three hundred metre span.

3. After the model was completed it had to be submitted to a special commission set up by the Academy of Sciences and invaded by foreign scientists and specialists at the time of Catherine II. They considered themselves to be much superior to Russian people whose intellect and talent they utterly ignored.

4. In spite of general disbelief the testing of the model was a success. No failure resulted even when a weight much greater than the maximum load was applied to the bridge. In spite of the favourable conclusion no practical result followed.

 

VII. Прочитайте 3 и 4-й абзацы текста и ответьте на вопросы письменно.

1.What commission did the model have to be submitted?

2. What specialists invaded the Academy of sciences at the time of Catherine II?

3. Did they consider themselves much superior to Russian people?

4. Was the testing of the model a success?

5. Did practical result follow?

 

Вариант 4

I. Перепишите следующие предложения, определите в каждом из них видовременную форму и залог глагола-сказуемого (см. образец). Переведите предложения на русский язык.

1.The automatic equipment is being installed in our shop.

2.Radioactive isotopes have been made in nuclear reactor.

3.The construction of this house will be completed in a month.

4.The engineer was asked about the new technology used at the plant.

 

II. Перепишите следующие предложения и переведите их на русский язык, обращая внимание на разные значения слов it, that, one.

1.The success in chemistry made it possible to obtain a lot of new materials.

2. One must apply the materials that can be machined easily.

3. It is the energy of falling water that is used to drive turbines.

 

III. Перепишите предложения и переведите их на русский язык, обращая внимание на различные значения глаголов to be, to have, to do.

1.The operators dealing with radioisotopes must have protective suits.

2.The engineers are to study the problem of using solar energy.

3.We had to use a computer to make these calculations.

4.One never knows what he can do.

 

IV. Перепишите следующие предложения и переведите их на русский язык, обращая внимание на бессоюзное подчинение.

1.I think the drawing will be ready by tomorrow.

2. The phenomenon Roentgen discovered is widely used in medicine.

 

V. Перепишите следующие предложения и переведите их на русский язык, обращая внимание на функцию инфинитива.

1.To design new buildings is the work of an architect.

2.To measure volumes we must know the dimensions of a body.

3.The purpose of this book is to describe certain properties of metals.

4.She is leaving for the conference to be held in Moscow.

 

VI. Прочитайте и переведите с 1 по 4-й абзацы текста. Перепишите и письменно переведите 1 и 3-й абзацы.

Пояснения к тексту:

1. to propel – приводить в движение

2. self-propelled – самоходный, самодвижущийся

3. engine – машина, двигатель.

 



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