- •Министерство образования и науки Российской Федерации Казанский государственный технический университет им. А.Н.Туполева
- •Английский язык
- •Lesson 1 Sequence of Tenses (Согласование времен)
- •Ex.2 Put the verbs in brackets into the Past Indefinite or the Past Perfect Tense.
- •The Passive Voice Страдательный залог
- •History Part I.
- •Part II.
- •Modern electronics
- •Exercises to the texts:
- •Listening and speaking.
- •Task 3. Check your answers to Task 3 with the help of the text and diagrams.
- •Task 4. Label each step in this flowchart with the correct letter from the list. The first one is done for you.
- •Task 5. Read the text below, then look at these statements. Are they true or false? You may need to use your own knowledge as well as information from the text.
- •Lesson 2 Reported Speech (Косвенная речь)
- •Exercises:
- •Reported Questions (Вопросы в косвенной речи).
- •Reported Commands and Requests Приказания и просьбы в косвенной речи
- •Alfred nobel - a man of contrasts.
- •Notes to the text.
- •Listening and speaking.
- •Task 4. Read this advice on 'Mixing down'. Listen again to Part 2. Then note the points in this text which are additional to those given on the tape.
- •Lesson 3. Conditional Sentences (Условные предложения)
- •Союзы, вводящие условные предложения.
- •Exercises:
- •What is an electric current?
- •Notes on the text
- •Words to be learnt.
- •Carbon dioxide emission
- •Listening and Speaking.
- •Course Guide
- •Information Technology
- •Lesson 4. The Participle.
- •Forms of the Participle II
- •Functions and translation
- •Complex Object with the Participle /сложное дополнение/
- •Complex Subject with the Participle.
- •Absolute Participle Construction /Независимый причастный оборот/.
- •Особенности перевода
- •Holographic technique helps in testing and research.
- •Words to be learnt
- •Listening and speaking.
- •Gerundial Object
- •Indefinite Gerund Passive (being written)
- •Сравнение герундия и причастия.
- •Exercises:
- •Sources of power
- •Notes on the Text:
- •Words to be learnt:
- •Revision
- •Listening and speaking
- •Lesson 6 The Infinitive
- •Формы инфинитива
- •Functions
- •Complex Object with the Infinitive.
- •It consists of two elements.
- •Complex Subject with the Infinitive
- •Grammar exercises
- •Ex.2 Translate the phrases with the Infinitive.
- •Ex.3 Grammar review.
- •Translate and define the functions of the infinitive.
- •Vocabulary to be learnt:
- •Ex. 3 Define the meanings of the phrases with international words.
- •Revision
- •Listening and speaking
- •Search reading
- •Read yourself
- •A new pedestrian crossing strategy
- •Viruses
- •2. Decide whether the following statements are true (t) or false (f) in relation to the information in the text. If you feel a statement is false, change it to make it true.
- •Database management systems
- •1. Review questions:
- •2. Translate the international words without a dictionary.
- •1. Review questions:
- •2. Translate the international words without a dictionary:
- •3. Define what parts of speech these words are and translate them:
- •Transistors and semiconductors
- •1. Review questions:
- •2. Translate the international words without a dictionary:
- •3. Explain what meanings prefixes and suffixes give to the following words and translate the words:
- •Amplifiers
- •1. Review questions:
- •2. Make up an abstract of the text basing on the answers to the above questions.
- •3. Define to what parts of speech these words belong and translate them:
- •Check yourself
- •Variant I Computers in our life
- •Grammar test
- •Variant II
- •Virtual worlds
- •Grammar test
- •Appendix 1
- •Appendix 2
- •Irreqular verbs
- •Appendix 3 Чтение дробных и смешанных величин
- •Словообразование (Word Formation) Суффиксы
- •Приставки
- •Derivatives
- •Synonyms
- •Opposites correct – wrong; continue – interrupt; free – bound; presence – absence; remain – leave; begin – complete, finish safe – dangerous
- •Vocabulary
- •Литература
1. Review questions:
1.What elements does a diode consist of ? 2.What metal is the plate made of? 3.What does a basic law of electricity state? 4.What charges are emitted from the cathode of an electron tube? 5.When is an electric field established within the tube? 6.For what purpose is a battery connected between the plate and the cathode of a diode? 7.What is the plate current? 8.When does the tube act like an open circuit? 9.What is space charge? 10.What is the effect (action) of the space charge?
2. Translate the international words without a dictionary:
to vary, to control, to absorb, to indicate, to tend, to limit, to discuss, to form
3. Define what parts of speech these words are and translate them:
direction, directive, directly, indirectly, director; partial, partially, partly, party; operator, operating, operation, operative, operatively; converter, convertible; dependable, dependent, dependence, dependency
Text 6 Read and translate the text.
Transistors and semiconductors
1. In recent years the transistor — an entirely new type of electron device — has come into its own1 and bids to replace the bulky electron tubes in many applications. Transistors are far smaller than tubes, have no filament and hence need no heating power. They are mechanically rugged, have practically unlimited life, and can do some jobs better than electron tubes, while catching up fast in other respects.2
2. In contrast to electron tubes, which utilize the flow of free electrons through a vacuum or gas, the transistor relies for its operation on the movement of charge carriers through a solid substance, a semiconductor. Transistors are only one of the family of semiconductors; many other semiconductor applications are becoming increasingly popular and new ones are constantly being discovered.
3. It is known that materials are classed as semiconductors if their electrical conductivity is intermediate between metallic conductors, which have a large number of free electrons available as charge carriers, and non-metallic insulators, which have practically no free electrons available to conduct current. The two semiconductors most frequently used in electronics and transistor manufacture are germanium and silicon. Both elements have the same crystal structure and similar characteristics, so that the discussion that follows for germanium will also apply to silicon.
4. It is known that outermost electron shell of an atom contains the loosely held valence electrons, which are easily dislodged to become electric current carriers. Germanium has four valence electrons in its outer shell, and for our purposes, the atom may be pictured as containing only these electrons and four protons in the nucleus to keep it electrically neutral.
5. When germanium is in crystalline form its atoms assume the typical diamond structure. In this structure adjacent germanium atoms share their valence electrons in a strong bond, so that effectively four orbital electron pairs are associated with each nucleus. These electron pairs are termed covalent bonds and they are bound so strongly to each other and to the nucleus that no free electrons are available to conduct a current through the germanium.
6. A pure germanium crystal, therefore, is practically a nonconductor of electricity. It is not completely non-conducting, since ordinary heat energy occasionally disrupts some of the covalent bonds, thus liberating free electrons as charge carriers.
7. If a small amount of an impurity is introduced into the germanium crystal, its current-conducting characteristics change radically. Thus, when atoms that have five electrons in their outer shell are introduced into the germanium, a procedure known as doping, the fifth electron of the impurity atom does not find a place in the symmetrical covalent-bond structure and, hence, is free to roam around through the crystal. These free electrons are then available as electric current carriers.
8. By placing an electric Yield across the "doped" germanium crystal, the excess of free electrons donated by the impurity atoms will travel toward the positive terminal of the voltage source. Relatively few impurity or "donor" atoms within the germanium structure permit fairly substantial electron currents through the crystal when an electric field is applied. Germanium that has been doped by pen-tavalent donor atoms is known to be n-type germanium, because current conduction is carried on with negative charge carriers, or electrons.
9. Consider now the situation when an impurity that has only three electrons in its outer shell is introduced into the pure germanium crystal. The trivalent indium atoms take their place in the germanium structure, but one of the covalent bonds around each indium atom has an electron missing,3 or a hole in its place. Although the hole indicates the absence of an electron it behaves like a real, positively charged particle when an electric field is applied across the crystal.
10. Under the influence of the electric field, electrons within the crystal will tend to move toward the positive terminal of the voltage source and jump into the available holes of the indium atoms near the positive terminal. Since there are no free electrons available, the deficient indium atoms near the positive terminal "steal'" electrons from their neighbors by disrupting their covalent bonds. This creates new holes in adjacent atoms.
11. As electrons move toward the positive terminal, the holes will move toward the negative terminal, thus acting like mobile, positive particles. As the holes reach the negative terminal, electrons enter the crystal near the terminal and combine with the holes, thus cancelling them.
12. At the same time, the loosely held electrons that filled the holes near the positive terminal are attracted away from their atoms into the positive terminal. This, of course, creates new holes near the positive terminal, which again drift toward the negative terminal. Current conduction may thus be considered to occur by means of holes inside the crystal, and by means of electrons through the external connecting wires and battery.
13. An impurity that has three electrons in its outer shell is known as an acceptor atom, because it takes electrons away from surrounding germanium atoms. Germanium that has been doped with trivalent acceptor atoms is called p-type germanium, to specify that current conduction is carried on by holes, which are the equivalent of positive charges.
Commentary
1. has come into its own — стал совершенно самостоятельным
2. while catching up fast in other respects — и широко применяется в других областях техники
3. an electron missing — недостающий электрон
EXERCISES: