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Файл:Английский язык = English. Учебное пособие-2
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Melting and Boiling Points. The temperature at which a metal melts, is
called the melting point, the metals of lower melting points are generally the
soft metals and those of high melting the hard metals.
The boiling point of a substance depends on the surrounding pressure.
The term “boiling point” refers to the temperature at which the metal boils
under normal atmospheric pressure.
Electrical Conductivity. The electrical conductivity of a substance is the
electrical conducting power of a unit length per unit of cross-sectional area.
The electrical resistance of metals or alloys is increased by decreasing the size
of the crystals and, therefore, increasing the number of crystal boundaries.
In general, all metals increase in resistivity with increase in impurities.
The resistivity of metals is also increased in most cases by an increase in
temperature.
Heat Conductivity. Heat conductivity is measured as the heat-conducting
ability of a unit length or thickness of a substance per unit of cross-sectional
area.
Magnetism. Magnetism is measured as the magnetic force exerted by a
unit volume of a substance under standard magnetizing force. Iron, cobalt
and nickel are the only metals possessing considerable magnetism at room
temperature, and they become non-magnetic when heated to a certain
temperature. Strong permanent magnets have been made chiefl y of one of
several compositions of steel, but in recent years a number of magnet alloys
of much greater magnetism have been developed.
Density and Porosity. Porosity, the quality of containing pores, is lack
of density. Density, on the other hand, denotes weight per unit of volume.
The distinction will be manifest from the fact that some heavy metals,
like grey cast ironware, are porous enough to leak under heavy hydraulic
pressures, whereas some lightweight metals, like aluminium, are dense and
compact.
Colour. Most of the metals are silvery white or grey in colour. Copper
is the only red metal, and gold is the only yellow one, although a number
of copper-base alloys are also yellow. All solid metals have metallic lustre,
although the true colour and lustre of many metals are often obscured by a
coating of oxide – which may be white, grey, red, brown, bluish, or black.
Notes:
the manner of arrangement – способ расположения;
space lattice – пространственная решетка;
close-packed cubic – кубическая с плотно упакованными атомами;
body-centred cubic – кубическая объемно-центрированная;
molybdenum – молибден;
tungsten – вольфрам;
191
hexagonal close-packed – гексагональная с плотно упакованными ато-
мами;
as the heat is lost from the mass – по мере того, как масса теряет тепло;
weight per unit of volume – вес на единицу объема.
21. Ответьте на следующие вопросы по тексту.
1. What are the main physical properties of metals and alloys?
2. What does the boiling point of a substance depend on?
3. When do most metals extend?
4. What is the diff erence between liquid and solid metals?
5. What metals possess considerable magnetism at room temperature?
22. Соедините термины и их значения в одну фразу.
1) porosity a) the temperature at which a metal melts
2) composition b) the electrical conducting power of a unit of
cross sectional area
3) melting point c) the quality of containing pores
4) boiling point d) the temperature at which the metal boils
under normal atmospheric pressure
5) electrical conductivity e) the manner of arrangement of metal atoms as
to geometric form in solid crystals
6) density f) weight per unit of volume
23. Найдите в тексте и прочитайте предложения, в которых употре-
бляются следующие слова и словосочетания. Поставьте вопросы к
этим предложениям.
Solid crystals; composition; surface; cooling; electrical resistance;
lightweight metals; to leak; resistivity; the solidifi ed mass; denseness.
24. Найдите в каждом абзаце слова, которые можно было бы вы-
нести перед текстом в качестве ключевых.
25. Разделите текст A на смысловые части и выделите в каждом его
абзаце предложение, передающее основную мысль.
26. Составьте подробный план текста, выделяя микротемы каж-
дой части и озаглавливая их.
27. Составьте резюме по содержанию прочитанного текста.
28. Перескажите текст А, пользуясь логико-смысловыми опорами.
192
29. Прочитайте текст B без использования словаря, определите, о
чем он, и ответьте на вопросы, данные после текста.
Text B. Foundry Metal Casting
One of the basic processes of the metalworking industry is the production of
metal castings. Numerous methods have been developed through the ages for
producing metal castings, but the oldest method is that of making sand castings
in the foundry. Primarily, work consists of melting metal in a furnace and pouring
it into suitable sand molds, where it solidifi es and assumes the shape of the mold.
However, the operation of making sand castings is not as simple as it seems.
Metal-castings methods may be classifi ed into three groups depending
upon the type of mold used and the manner in which the molten metal is
introduced into the mold.
The mold may be made from heat-resisting material, such as sand, some
suitable ceramic material, or plaster. The kind of material chosen to make
the mold is, of course, determined primarily by the melting temperature of
the cast metal. Molten metals may be poured into the mold by gravity or,
on the other hand, pressure may be applied to force the liquid metal into the
mold. The latter method is known as die casting. Die-casting pressure may
be furnished by air, hydraulic means, mechanical means, or centrifugally.
Among the mold materials, sand is used more than all others, since it can
be packed to any required shape with small eff ort.
This method of production is relatively simple, inexpensive, and is not
limited to any particular type of metal or to certain sizes and shapes of castings.
Of course, sand molds are used only once, and each casting requires a new mold.
Wider use of the permanent type of mold made from steel, iron or any
other suitable metal, depending upon the melting temperature of the cast
metal, is therefore greatly desired.
Bronze molds are employed at times for casting metals and alloys of very
low melting temperature such as zinc-base and lead-base alloys.
Modern casting techniques also permit that steel molds, coated inside
with refractory material, also be successfully used for production of iron and
steel castings.
The metal molds are usually made of two parts which are either clamped
together or closed by a screw or other suitable device. The molten metal may
be introduced into the mold either by gravity or pressure.
The inner surfaces of the metal mold are in most cases fi nished smooth.
They can be re-used. These qualities make them superior to sand castings.
Notes:
method of sand castings – метод литья в земляные формы;
furnace – печь;
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mold – форма, шаблон;
die casting – литье под давлением;
at times – иногда.
1. What is the oldest method of casting?
2. How may metal-casting methods be classifi ed?
3. Put the steps in the right order according to the technology:
• pouring the metal into suitable sand molds;
• solidifying;
• making sand molds;
• melting metal in a furnace.
4. Why is sand used as mold material?
5. What other mold materials do you know?
6. What methods of pouring molten metals into a mold do you know?
7. What does the melting temperature of the cast metal determine?
30. Составьте резюме по содержанию прочитанного текста.
31. Прочитайте текст С, постарайтесь понять его содержание и выполните послетекстовые задания.
Text C. Machine Tools
Machine tools are used to shape metals and other materials. The material
to be shaped is called the workpiece. Most machine tools are now electrically
driven. Machine tools with electrical drive are faster and more accurate than
hand tools: they were an important element in the development of massproduction processes, as they allowed individual parts to be made in large
numbers so as to be interchangeable.
All machine tools have facilities for holding both the workpiece and the tool,
and for accurately controlling the movement of the cutting tool relative to the
workpiece. Most machining operations generate large amounts of heat, and use
cooling fl uids (usually a mixture of water and oils) for cooling and lubrication.
Machine tools usually work materials mechanically but other machining
methods have been developed lately. They include chemical machining,
spark erosion to machine very hard materials to any shape by means of
a continuous high-voltage spark (discharge) between an electrode and a
workpiece. Other machining methods include drilling using ultrasound, and
cutting by means of a laser beam. Numerical controls of machine tools and
fl exible manufacturing systems have made it possible for complete systems of
machine tools to be used fl exibly for the manufacture of a range of products.
Lathe is still the most important machine tool. It produces parts of circular
cross-section by turning the workpiece on its axis and cutting its surface
194
with a sharp stationary tool. The tool may be moved sideways to produce
a cylindrical part and moved towards the workpiece to control the depth of
cut. Nowadays all lathes are power-driven by electric motors. That allows
continuous rotation of the workpiece at a variety of speeds. The modern lathe
is driven by means of a headstock supporting a hollow spindle on accurate
bearings and carrying either a chuck or a faceplate, to which the workpiece
is clamped. The movement of the tool, both along the lathe bed and at right
angle to it, can be accurately controlled, so enabling a part to be machined to
close tolerances. Modern lathes are often under numerical control.
Note:
spark erosion – электроэрозионная обработка.
32. Найдите в тексте и прочитайте предложения, в которых употребляются следующие слова и словосочетания. Поставьте вопросы к
этим предложениям.
To shape metals; workpiece; electrically driven machine tools; an
important element; machining operations; chemical machining; a laser beam;
circular cross-section; cylindrical part; modern lathe.
33. Прочитайте текст еще раз, разделите его на смысловые части и
подберите к ним названия.
34. Составьте план текста и перескажите его в соответствии с планом.
TEST
1. Из предложенных вариантов ответов выберите один правильный.
1. He agreed … the job as soon as possible.
a) start c) to start
b) starting d) starts
2. The teacher always expected me … well in exam.
a) did c) do
b) doing d) to do
3. Let me … for the meal. You paid last time.
a) pay c) paid
b) to pay d) paying
4. You can’t … your car outside the university.
a) parks c) park
b) to park d) parking
195
5. His words made me … uncomfortable.
a) to feel c) feel
b) feeling d) feels
6. Has the secretary come yet? I want my papers … .
a) to type c) typed
b) type d) to be typed
7. Our English teacher told us … shy and speak English as much as possible.
a) not to feel c) felt
b) not feel d) feel
8. The English colony, Plymouth, in Massachusetts, is known … by the
Piligrims who arrived on the Mayfl ower in 1620.
a) to be established c) to have been establishing
b) to have established d) to have been established
9. He is likely … on Sunday.
a) came c) to come
b) coming d) come
10. He is thought … now.
a) to study c) to have been studied
b) to be studying d) study
2. Прочитайте текст и составьте резюме по содержанию прочитанного.
50 years ago people didn’t even hear of computers, and today we cannot
imagine life without them.
Computer technology is the fastest-growing industry in the world. The
fi rst computer was the size of a minibus and weighed a ton. Today, its job can
be done by a chip the size of a pin head. And the revolution is still going on.
Very soon we’ll have computers that we’ll wear on our wrists or even in
our glasses and earrings.
The next generation of computers will be able to talk and even think
for themselves. They will contain electronic “neural networks”. Of course,
they’ll be still a lot simpler than human brains, but it will be a great step
forward. Such computers will help to diagnose illnesses, fi nd minerals,
identify criminals and control space travel.
Computers save a lot of time. They seldom make mistakes. It’s much
faster and easier to surf the Internet than to go to the library. Online shopping
makes it possible to fi nd exactly what you want at the best price, saving both
time and money. E-mail is a great invention, too. It’s faster than sending a
letter and cheaper than sending a telegram.
All in all, computers are a useful tool. They have changed our life for the
better. So why shouldn’t we make them work to our advantage?
196
UNIT X. Environmental Protection.
Forms of Energy
Vocabulary
Oral Practice: Environmental Protection
Grammar: Герундий (Gerund)
Reading and Speaking Practice:
Text А. Electricity
Text B. Kinds of Electricity
Text С. Energy Development
Test
VOCABULARY
1. Прочитайте и запомните новые слова, познакомьтесь с их русскими эквивалентами; переведите предложения на русский язык.
1. alternating current [ˈɔːltɜːneɪtɪŋ ˈkʌrənt] переменный ток
Alternating current reverses the direction of its fl ow many times a second.
2. bare [beə] adj. неизолированный
An electric current can kill you if you touch a bare wire with wet hands or
while standing on a wet fl oor.
3. belt [belt] n. пояс; ремень
The belt had coiled itself round the wheel, stopping the motor.
4. by-product [ˈbaɪ prɒdʌkt] n. побочный продукт
The invaluable by-products are wasted and escape into the form of smoke.
5. charge [tʃɑːdʒ] n. заряд; нагрузка; цена
Both electrons and protons have an electric charge.
6. consumption [kənˈsʌmpʃn] n. потребление; расход
The Government wants to reduce tobacco consumption by 40%.
7. to contain [kənˈteɪn] v. содержать в себе; вмещать
The new directory contains a lot of useful addresses and telephones.
8. direct current [dɪˈrekt ˈkʌrənt] постоянный ток
Direct current fl ows in only one direction.
9. discharge [dɪsˈtʃɑːdʒ] n. разряд; сток, слив
Discharges can also have thermal eff ects.
10. drill [drɪl] n. сверло; дрель; бур
In a hammer drill the hammer me chanism works separately from the
rotation mechanism.
197
11. electricity [ɪlekˈtrɪsɪtɪ] n. электричество
The new lights consume less electricity.
12. to emit [ɪˈmɪt] v. выделять; издавать
The factory has been emitting black smoke from its chimneys which is
against the law.
13. fl ash [fl æʃ] n. вспышка; проблеск
A fl ash of lightning lit up the night sky.
14. fl ow [fl əʊ] n. поток; течение
The dam regulates the fl ow of water into the river.
15. gasoline [ˈɡæsəliːn] n. газолин; амер.
1
бензин
The gasoline powers the engines.
16. generator [ˈdʒenəreɪtər] n. генерaтор; производитель
They scarcely ever used the emergency generator.
17. incomplete combustion [ˌɪnkəmˈpliːt kəmˈbʌstʃən] неполное сго-
рание
Pollutants are products of incomplete combustion in internal-combustion
engines, road dust and wood smoke.
18. internal-combustion engine [ɪnˈtɜːnl kəmˈbʌstʃən ˈendʒɪn] двига-
тель внутреннего сгорания
Internal-combustion engines can be powered by any fuel that can be
combined with an oxidizer in the chamber.
19. lightning [ˈlaɪtnɪŋ] n. молния
Lightning is a natural occurrence.
20. to occur [əˈkɜː] v. случаться; встречаться; происходить
Brazing occurs at temperatures in excess of 450 °C.
21. particle [ˈpɑːtɪkl] n. частица
Every particle of matter attracts every other particle.
22. precision [prɪˈsɪʒn] n. точность
The work was done with surgical precision.
23. renewable [rɪˈnjuːəbəl] adj. возобновляемый
Wind and water are renewable fuel sources.
24. satellite [ˈsætəlaɪt] n. спутник
The Moon is a satellite of the Earth.
25. socket [ˈsɒkɪt] n. патрон; розетка
When the plug is inserted in the socket, the lamp can be lighted.
26. spark plug [spɑːk plʌɡ] свеча зажигания
Motor vehicles equipped with spark plugs use electric sparks to explode
the gasoline that runs their engines.
27. tiny [ˈtaɪnɪ] adj. крошечный
The computer chips are tiny.
28. wire [ˈwaɪə] n. провод; проволока
The wire must not contact the metal cover.
1
амер. – американизм
198
2. Прочитайте следующие словосочетания с новой лексикой и переведите их на русский язык, обращая внимание на сочетаемость слов.
Alternating current, a bare wire, safety belt, to fasten one’s belt, an invaluable
by-product, to be on charge, fuel consumption, to contain useful information,
direct current, discharge from a chemical plant, the discharge of steam, an electric
drill, static electricity, to be worked by electricity, to emit rays, to emit clouds
of smoke into the air, fl ashes of lightning, a steady fl ow, premium gasoline, an
emergency generator, incomplete combustion, an internal-combustion engine,
forked lightning, to occur in nature, elementary particles, utmost precision,
renewable fuel sources, a communications satellite, to put an electric plug into a
socket, spark plug, a tiny room, copper wire, a length of wire.
3. Поставьте разные типы вопросов к следующим предложениям.
1. Both electrons and protons have an electric charge.
2. The Government wants to reduce tobacco consumption by 40%.
3. The dam regulates the fl ow of water into the river.
4. The work was done with surgical precision.
5. Wind and water are renewable fuel sources.
6. The Moon is a satellite of the Earth.
4. Образуйте словосочетания и предложения с новыми словами.
ORAL PRACTICE
5. Прочитайте текст. Поставьте к нему разные типы вопросов и
дайте на них краткие и полные ответы.
ENVIRONMENTAL PROTECTION
Our planet is only a tiny part of the Universe, but nowadays it’s the only
place where we can live. People always polluted their surroundings, but until
now pollution was not such a serious problem. People lived in rural areas and
did not produce such amount of polluting agents that would cause a dangerous
situation in global scale. With the development of overcrowded industrial highly
developed cities, which put huge amounts of pollutants into surroundings, the
problem has become more and more dangerous. Today our planet is in serious
danger. Acid rains, global warming, air and water pollution, and overpopulation
are the problems that threaten human existence on the Earth.
In order to understand how pollution aff ects our body, people must
understand exactly what pollution is. There are several types of pollution:
199
air, water, soil and even thermal and noise pollution. Air pollution hits our
body mainly through the respiratory system.
The pollutants that harm our respiratory system are known as particulates.
Particulates are small solid particles which can be seen through rays
of sunlight. They are products of incomplete combustion in internalcombustion engines, road dust and wood smoke. Billions of tons of coal
and oil are consumed around the world every year. When these fuels burn,
smoke and other by-products are emitted into the atmosphere. Although wind
and rain can occasionally wash away the smoke, given off by power plants
and automobiles. These chemical compounds undergo a series of chemical
reactions in the presence of sunlight, and as a result there is smog, a mixture
of fog and smoke. While such pollutants are seen, other harmful particles are
not visible. Among the most dangerous to our health are carbon monoxide
(CO), nitrogen oxides, sulfur dioxide, and ozone or active oxygen.
Whenever felt dizzy or light-headed being in an enclosed parking garage
or a tunnel, one should be aware he has felt the eff ect of carbon monoxide.
This odorless, colourless, but poisonous gas is produced by the incomplete
burning of fossil fuels, like gasoline or diesel fuel.
Factories emit tons of harmful chemicals. These emissions have
disastrous consequences for our planet and people. It is the main reason for
the greenhouse eff ect and acid rains.
Our forests are disappearing because they are cut down or burnt. If this
trend continues, one day people won’t have enough oxygen to breathe and
mankind won’t see beautiful green forests at all.
Lakes, seas and even oceans together with the groundwater are aff ected
by human activity. Industries discharge a variety of pollutants in their
wastewater including heavy metals, organic toxins, oils, nutrients, and
solids. Discharges can also have thermal eff ects, especially those from power
stations, and these too reduce the available oxygen. If nothing is done about
it, one day nothing will be able to live in our oceans.
Every ten minutes one kind of animal, plant or insect dies out forever. It
is mainly caused by human activity. If nothing is done about it, one million
species that are alive today may soon become extinct.
And even greater threats are nuclear power stations. We all are familiar
with the tragic and horrible consequences of the Chernobyl disaster.
Fortunately, it’s not too late to solve all these problems. People still have the
time, the money and even the technology to make our planet a better, cleaner and
safer place. And it is now more than ever apparent that destroy
ing our enviroment
we, at the same time, are destroying ourselves and our future generations.
Notes:
surroundings – окрестности; среда; окружение;
overcrowded – переполненный; перенаселенный;
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