Text 7. Semi-conductors

1. Прочтите и переведите текст.

Vocabulary:

semi-conductors – полупроводники

to mean (meant, meant) – означать

to range – колебаться (в определенных пределах)

variety – разнообразие

silicon – кремний

germanium – германий

selenium – селен

phosphorus – фосфор

chemical compounds – химические соединения

oxides – окиси

sulphides – сульфиды

to influence – влиять

sharply – резко повышаться

dependence – зависимость

prospects – перспективы

to employ – применять, использовать

to apply – прикладывать, употреблять, обращаться

engine – двигатель

to count – считать

emergency signals – аварийная сигнализация

counter – счетчик

photocells – фотоэлементы

amount – количество, сумма, итог

fraction – доля, часть

thermocouple – термоэлемент

means – способы

to maintain – поддерживать

to vary – изменяться

wide range – широкие пределы

zero – ноль

The term “semi-conductors” means “half-conductors”, that is, a material whose conductivity ranges between that of conductors and non-conductors of insulators.

They include a great variety of elements (silicon, germanium, selenium, phosphorus and others), many chemical compounds (oxides, sulphides) as well as numerous ores and minerals.

While the conductivity of metals is very little influenced by temperature, the conductivity of semi-conductors increases sharply with heating and falls with cooling. This dependence has opened great prospects for employing semi-conductors in measuring techniques. Light as well as heat increases the conductivity of semi-conducting materials, this principle being used in creating photo resistances. It is also widely applied for switching on engines, for counting parts on a conveyer belt, as well as for various systems of emergency signals and for producing react to all kinds of radiations and are therefore employed in designing electronic counters.

Converting heat into electricity without using boilers or other machines was one of the most complicated engineering problems. This could be done by means of metal thermocouples, which later were made of semi-conductors that generated ten times as much electricity as the metal ones.

Sunlight, like heat, can feed out electric circuits. Photocells made of semi-conducting materials are capable of transforming ten per cent of sun-ray energy; we obtain only fractions of one per cent of electric power. The electricity generated by semi-conductor thermocouples can produce not only heat but also cold, this principle being used in manufacturing refrigerators.

Semi-conducting materials are also excellent means of maintaining a constant temperature irrespective of the surrounding temperature changes. The latter can vary over a wide range, for example, 50 below 0° to 100° above 0°.

Semi-conductors are determining the progress of radio engineering, automation, chemistry, electrical engineering and many other fields of science and technique.

2. Ответьте на вопросы по тексту:

1. What does the term “semi-conductor” mean?

2. What happens to the semi-conductor’s conductivity with the lowering of temperature?

3. Can light increase the conductivity of semi-conductors?

4. What was one of the main engineering problems which could be solved by means of semi-conductors?

5. What principle is used in manufacturing refrigerators?

3. Переведите с русского языка на английский язык:

1. Полупроводники – это материалы, способные проводить ток.

2. Полупроводники имеют обширное применение в измерительной технике.

3. Проводимость полупроводниковых материалов резко повышается при нагревании.

4. Кроме применения в технике, полупроводники уже широко используются в повседневной жизни.

5. Полупроводниковые фотоэлементы способны преобразовывать энергию солнца в электричество.

4. Определите базовые существительные в каждой группе слов. Переведите.

1. The Academy of Science Institute of Semi-Conductors.

2. Semi-conductor thermo-electric generator.

3. Current-carrying conductor.

4. Electrical engineering problem.

5. Emergency signal system.

6. High temperature range.

7. Cotton insulation layer.

8. Energy accumulation process.

9. Electronic counting machine.

5. Выберите правильный вариант ответа:

1. What is “semi-conductor”?-It is …

a) conductor b) non-conductor c) insulator d) half-conductor

2. The conductivity of semi-conductor …

a) falls with heating b) increases with heating

3. Light …

a) decreases the conductivity of semi-conducting material

b) increases the conductivity of semi-conducting material

4. Semi-conductors react …

1. to all kinds of radiations b) not to all kinds of radiations

5. Metal thermocouples made of semi-conductors generate …

1. a) ten times as much electricity as metal ones

b) ten times less electricity than metal ones

6. Sunlight, like heat, …

a) can feed our electric circuits b) cannot feed our electric circuits

7. Electricity generated by semi-conductors …

a) can produce heat b) can produce cold

c) cannot produce heat and cold d) can produce heat and cold