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Упражнение 1. A. Прочитайте словосочетания из текста НА и постарайтесь понять значения выделенных слов.

1. the threshold of а new technological age
2. who was awarded the Noble Prize
3. which won for them the Noble Prize
4. their quality is often uneven
5. начало новой технологической эры
6. кому присудили Нобелевскую премию
7. за что они получили Нобелевскую премию.
8. их качество часто бывает неодинаковым.
9. Подберите к каждому выделенному в А слову соответствующее ему по значению.
10. give or grant (by official decision) 3
11. irregular, changing с start, beginning 4
12. get by means of hard work or struggle as a result of competition 2

Упражнение 2. A. Прочитайте текст и постарайтесь понять значения терминов memory cells, windings, coils.

The practical applications of superconductivity are limited because of the very low temperatures required. Some materials, for example lead, become almost perfect conductors at very low temperatures at the absolute zero (-273 °C). However, a number of uses have been proposed.

If a current is induced by a magnetic field in a ring of superconducting material, it will continue to circulate when the magnetic field is removed. In theory this could be made use of in the memory cells of computers. Memory cells made of superconducting material could store information indefinitely. Because of the zero resistivity of the cells, the information could be retrieved quickly, as fast as 10 -8 seconds.

90 per cent of the total losses in modern transformers is due to the resistance of the windings. Transformers could be made with windings cooled to the low temperature at which superconductivity occurs. The resistance would be zero and the transformer would be almost ideal. Similarly, a 100 % efficient electric motor has been proposed using the magnetic field of superconducting coils.

memory cells, windings, coils.

Клетки памяти, обмотка, катушки.

1. Подберите к каждому слову в колонке А соответствующее из колонки В.

1. induce E
2. remove F
3. indefinitely B
4. memory cell G
5. retrieve A
6. winding C
7. coil D

1. find, get back
2. unlimitedly

с spiral

1. length of wire wound in a spiral to conduct electric current
2. bring about

f take off, away

1. the unit of computer which stores data for future use

С Найдите в тексте, приведенном в А, три пары синонимов.

Ideal – perfect

Store- retrieve

Make -occur

Упражнение 3. Заполните пропуски словами conduct, superconductivity, superconductor, superconductive.

1 Superconductivity at high temperatures was almost discovered in 1979.

2. The Russian scientists found an oxide of metal they were experimenting with to conduct electric current. Moreover, the lower the temperature, the less resistance the material had.
3. The resistance continued to fall in liquefied nitrogen. To continue the experiments, they needed liquid helium. To obtain it was quite a problem at that time. So the experiments were stopped.
4. But it was this compound of copper, lanthanum and oxygen that proved to be a superconductor for which the Swiss physicists were honoured with a Noble Prize in 1987.
5. Later neither efforts nor money were spared (жалеть, экономить) for the study of the superconductive materials. Moreover, there were no longer any problems with helium.

Упражнение 4. A. Назовите 15-20 ключевых слов и словосочетаний на тему:

«Superconductivity research».

1. superconductivity
2. to limit
3. low
4. temperatures
5. conductors
6. to propose
7. magnetic
8. field
9. Memory cells
10. information
11. indefinitely
12. to retrieve
13. transformer
14. zero
15. coils
16. conductivity

1. Speak about:

Latest achievements in conductivity research

Researchers from Tokyo Metropolitan University have shown that a quantity known as thermoelectric conductivity is an effective measure for the dimensionality of newly developed thermoelectric nanomaterials. Studying films of semiconducting single-walled carbon nanotubes and atomically thin sheets of molybdenum sulfide and graphene, they found clear distinctions in how this number varies with conductivity, in agreement with theoretical predictions in 1D and 2D materials. Such a metric promises better design strategies for thermoelectric materials.

Thermoelectric devices take differences in temperature between different materials and generate electrical energy. The simplest example is two strips of different metals welded together at both ends to form a loop; heating one of the junctions while keeping the other cool creates an electrical current. This is called the Seebeck effect. Its potential applications promise effective usage of the tremendous amount of power that is wasted as dissipated heat in everyday life, whether it be in power transmission, industrial exhaust, or even body heat. In 1993, it was theorized that atomically thin, one-dimensional materials would have the ideal mix of properties required to create efficient thermoelectric devices. The resulting search led to nanomaterials such as semiconducting single-walled carbon nanotubes (SWCNTs) being applied.

However, there was an ongoing issue that prevented new designs and systems from being accurately characterized. The key properties of thermoelectric devices are thermal conductivity, electrical conductivity, and the Seebeck coefficient, a measure of how much voltage is created at the interface between different materials for a given temperature difference. As material science advanced into the age of nanotechnology, these numbers weren’t enough to express a key property of the new nanomaterials that were being created: the «dimensionality» of the material, or how 1D, 2D or 3D-like the material behaves. Without a reliable, unambiguous metric, it becomes difficult to discuss, let alone optimize new materials, particularly how the dimensionality of their structure leads to enhanced thermoelectric performance.