polunina_ln_bobrovskaia_im_priroda_nauka_tekhnologii

developed by Marvin Minsky in 1961 and the scanning acoustic microscope (SAM) developed by Calvin Quate and coworkers in the 1970s, that made it possible to see structures at the nanoscale. Various techniques of nanolithography such as optical lithography, X-ray lithography or nanoimprint lithography were also developed. Lithography is a top-down fabrication technique where a bulk material is reduced in size to nanoscale pattern.

(2)Another group of nanotechnological techniques include those used for fabrication of nanowires, those used in semiconductor fabrication such as deep ultraviolet lithography, electron beam lithography, focused ion beam machining, nanoimprint lithography, atomic layer deposition, and molecular vapor deposition. However, all of these techniques preceded the nanotech era, and are extensions in the development of scientific advancements rather than techniques which were devised with the sole purpose of creating nanotechnology and which were results of nanotechnology research.

(3)The top-down approach anticipates nanodevices that must be built piece by piece in stages, much as manufactured items are made. Scanning probe microscopy is an important technique both for characterization and synthesis of nanomaterials. Atomic force microscopes and scanning tunneling microscopes can be used to look at surfaces and to move atoms around. By using, for example, featureoriented scanning-positioning approach, atoms can be moved around on a surface with scanning probe microscopy techniques.

(4)In contrast, bottom-up techniques build or grow larger structures atom by atom or molecule by molecule. These techniques include chemical synthesis, self-assembly and positional assembly. Dual polarisation interferometry is one tool suitible for characterisation of self assembled thin films. Another variation of the bottom-up approach is molecular beam epitaxy or MBE. Researchers at Bell Telephone Laboratories developed and implemented MBE as a research tool in the late 1960s and 1970s. MBE allows scientists to lay down atomically precise layers of atoms and, in the process, build up complex structures. However, new therapeutic products, based on responsive nanomaterials, such as the ultradeformable, stress-sensitive Transfersome vesicles, are under development and already approved for human use in some countries.

(Adapted from Wikipedia, the Free Encyclopedia)

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1. Read the text and decide whether the following statements are TRUE, FALSE or there is NO such INFORMATION in the text.

2. Decide which part of the text contains the following information.

1.Atomic force microscopes and scanning tunneling microscopes are used to move atoms around.

2.Molecular beam epitaxy was developed as a research tool in the late 1960s and 1970s.

3.Give the answer to the following question.

What is lithography?

1.Lithography is a bottom-up technique where larger structures are build atom by atom or molecule by molecule.

2.Lithography is a nanotechnological technique used for fabrication of nanowires only.

3.Lithography is a bottom-up technique developed by the researchers at Bell Telephone Laboratories in the late1960s and 1970s.

4.Lithography is a top-down technique where a material is reduced in size to nanoscale pattern.

4. What is the main idea of the text?

1.The top-down techniques are expensive and time-consuming for mass production but very suitable for laboratory experimentation.

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2.The atomic force microscope and the Scanning Tunneling Microscope launched nanotechnology.

3.There are several developments of nanotechnological techniques which are very important for the modern society.

4.New therapeutic products, based on responsive nanomaterials, have been already approved for human use in some countries.

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UNIT 12

TRANSPORTATION

WARMING UP

1.Using your own words, try to define the term transportation.

2.What’s you favourite method of transportation?

3.What transportation problems are there in your country?

4.What will the transportation of the future be like?

READING

An automobile is a self-propelled vehicle used primarily on public roads but adaptable to other surfaces. Automobiles changed the world during the 20th century, particularly in the United States and other industrialized nations. From the growth of suburbs to the development of elaborate road and highway systems, the so-called horseless carriage has forever altered the modern landscape. The manufacture, sale, and servicing of automobiles have become key elements of industrial economies. But along with greater mobility and job creation, the automobile has brought noise and air pollution, and automobile accidents rank among the leading causes of death and injury throughout the world. But for better or worse, the 1900s can be called the Age of the Automobile, and cars will no doubt continue to shape our culture and economy well into the 21st century.

Automobiles are classified by size, style, number of doors, and intended use. The typical automobile, also called a car, auto, motorcar, and passenger car, has four wheels and can carry up to six people, including a driver. Larger vehicles designed to carry more passengers are called vans, minivans, omnibuses, or buses. Those used to carry cargo are called pickups or trucks, depending on their size and design. Minivans are van-style vehicles built on a passenger car frame that can usually carry up to eight passengers. Sport-utility vehicles, also known as SUVs, are more rugged than passenger cars and are designed for driving in mud or snow.

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Auto manufacturing plants in 40 countries produced a total of 63.9 million vehicles, including 42.8 million passenger cars, in 2004, according to Ward’s Auto, an auto industry analyst. About 16.2 million vehicles, including 6.3 million passenger cars, were produced in North America in 2004.

The automobile is built around an engine. Various systems supply the engine with fuel, cool it during operation, lubricate its moving parts, and remove exhaust gases it creates. The engine produces mechanical power that is transmitted to the automobile’s wheels through a drivetrain, which includes a transmission, one or more driveshafts, a differential gear, and axles.

Suspension systems, which include springs and shock absorbers, cushion the ride and help protect the vehicle from being damaged by bumps, heavy loads, and other stresses. Wheels and tires support the vehicle on the roadway and, when rotated by powered axles, propel the vehicle forward or backward.

Steering and braking systems provide control over direction and speed. An electrical system starts and operates the engine, monitors and controls many aspects of the vehicle’s operation, and powers such components as headlights and radios. Safety features such as bumpers, air bags, and seat belts help protect occupants in an accident.

Gasoline internal-combustion engines power most automobiles, but some engines use diesel fuel, electricity, natural gas, solar energy, or fuels derived from methanol (wood alcohol) and ethanol (grain alcohol).

Most gasoline engines work in the following way: turning the ignition key operates a switch that sends electricity from a battery to a starter motor. The starter motor turns a disk known as a flywheel, which in turn causes the engine’s crankshaft to revolve. The rotating crankshaft causes pistons, which are solid cylinders that fit snugly inside the engine’s hollow cylinders, to move up and down. Fuelinjection systems or, in older cars, a carburetor deliver fuel vapor from the gas tank to the engine cylinders.

The pistons compress the vapor inside the cylinders. An electric current flows through a spark plug to ignite the vapor. The fuel mixture explodes, or combusts, creating hot expanding gases that push the pistons down the cylinders and cause the crankshaft to rotate. The

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crankshaft is now rotating via the up-and-down motion of the pistons, permitting the starter motor to disengage from the flywheel.

(From Microsoft Encarta, 2008)

Expand your vocabulary

to propel – приводить в движение vehicle – транспортное средство wheel – колесо

cargo – груз truck – грузовик

engine – двигатель

gear – передаточный механизм; привод axle – ось

to steer – править рулем, управлять (автомобилем) to brake – тормозить

vapor – пар; пары; испарения

POST-READING ACTIVITY

1. Answer the following questions.

1. What is an automobile?

2. How are automobiles classified? What is the typical automobile? 3. What power does the engine produce?

4. What engines do most automobiles have?

5. How do most gasoline engines work?

2. In each line, three words rhyme, but one is different. Underline the one that is different. The two sounds are given to help you [t∫] or [∫].

3. Scan each line and match the words with the similar meaning.

4. Form the adjectives from the words given below. Use the following suffixes:

5. Transform the sentences into the question tags.

1.Automobiles changed the world during the 20th century.

2.The manufacture, sale, and servicing of automobiles have become key elements of industrial economies.

3.Automobiles are not classified by the number of passengers only.

4.The automobile is built around an engine.

5.The rotating crankshaft causes pistons to move up and down.

6.The pistons compress the vapor inside the cylinders.

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6. Put questions to the words or word expressions in the bold type.

1.The typical automobile has four wheels and can carry up to six people, including a driver.

2.Various systems supply the engine with fuel, cool it during operation, lubricate its moving parts, and remove exhaust gases it creates.

3.Suspension systems, which include springs and shock absorbers, cushion the ride and help protect the vehicle from being damaged.

4.Steering and braking systems provide control over direction and speed.

5.Most gasoline engines work in the following way: turning the ignition key operates a switch that sends electricity from a battery to a starter motor.

LANGUAGE IN USE

7. Read the text and fill in the gaps with the proper words in brackets.

Electric Motors and Generators

Electric motors and generators are a group of devices used to convert (1) … (mechanic/mechanical/mechanism) energy into electrical energy, or electrical energy into mechanical energy, by electromagnetic means. A machine that converts mechanical energy into electrical energy is called a generator, alternator, or dynamo, and a machine that converts electrical energy into mechanical energy is called a motor.

Two related (2) … (physics/physical/physic) principles underlie the operation of generators and motors. The first is the principle of electromagnetic (3) … (inductivity/induction/inductor) discovered by the British (4) … (science/scientific/scientist) Michael Faraday in 1831. If a conductor is moved through a magnetic field, or if the strength of the magnetic field acting on a stationary conducting loop is made to (5) … (vary/various/variety), a current is set up or induced in the conductor. The converse of this principle is that of electromagnetic reaction, first observed by the French (6) … (physics/physicist/physical)

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André Marie Ampère in 1820. If a current is passed through a conductor located in a magnetic field, the field exerts a mechanical force on it.

The simplest of all dynamoelectric machines is the disk dynamo (7) … (developed/developing/develop) by Faraday. It consists of a copper disk mounted so that part of the disk, from the center to the edge, is between the poles of a horseshoe magnet. When the disk is (8) … (rotating/rotates/rotated), a current is induced between the center of the disk and its edge by the action of the field of the magnet. The disk can be made to operate as a motor by (9) … (applied/applying/apply) a voltage between the edge of the disk and its center, causing the disk to rotate because of the force produced by magnetic reaction.

The magnetic field of a permanent magnet is (10) … (strong/strongly/stronger) enough to operate only a small practical dynamo or motor. As a result, for large machines, electromagnets are employed. Both motors and generators consist of two (11) … (basical/basic/basically) units, the field, which is the electromagnet with its coils, and the armature, the structure that (12) … (supporting/support/supports) the conductors which cut the magnetic field and carry the induced current in a generator or the exciting current in a motor. The armature is usually a laminated soft-iron core around which conducting wires are wound in coils.

(Abridged from Microsoft Encarta, 2008)

8. Read the text and fill in the gaps with the articles where necessary.

Carburetor

Carburetor is (1) … device that mixes (2) … fuel and air for burning in an internal-combustion engine. A carburetor atomizes (converts into a vapor of tiny droplets) liquid gasoline. An airflow carries (3) … atomized gasoline to the engine’s cylinders, where the gas is ignited.

The carburetor has been part of (4) … internal-combustion engines since the beginning of (5) … 20th century. In most passenger vehicles and light trucks built since 1985 the carburetor has been replaced by fuel injection, (6) … more efficient, computer-controlled method of

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injecting fuel into (7) … engine. Diesel engines, because of their design, have always used (8) … fuel injection instead of (9) … carburetors. Carburetors today are found only on older gasoline engines in cars and trucks. They are still common in boat engines, aircraft engines, and some sports vehicles, including jet-skis and motorcycles.

The basic carburetor is built around (10) … hollow tube called a throat, or barrel. Downward motion of the engine’s pistons creates a partial vacuum inside the cylinders that draws (11) … air into the carburetor’s throat and past a nozzle that sprays fuel. (12) … mixture of air and fuel produced inside the carburetor is delivered to (13) … cylinders for combustion.

A carburetor can be adjusted to mix larger or smaller amounts of air with the fuel. An idling engine at normal operating temperature requires an air-to-fuel ratio of about 15-to-1 (by weight) to completely burn (14) … fuel. Raising or lowering the air ratio makes (15) … mix either lean (containing less fuel) or rich (containing more fuel). (16) … lean mixture produces a cleaner, hotter combustion for cruising speeds, but not enough fuel for starting (17) … engine efficiently or allowing it to produce more power. A rich mixture is easier for the engine to burn, but produces more pollutants as (18) … byproducts.

The carburetor is adjusted to provide a rich mixture for (19) … cold engine starts because the rich mixture burns easier and longer. As the engine warms up, the carburetor alters the air-fuel ratio for (20) … leaner mixture.

(Abridged from Microsoft Encarta, 2008)

9. Read the text and fill in the gaps with the suitable words from the box.

Gasoline Engines

Gasoline engines have the (1) … over diesel in being lighter and able to work at higher rotational speeds and they are the usual choice

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