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SIMULATING —A NEW WAY OF CREATING MATERIALS





 

Mankind waited a long time for bronze. But when it arrived, it brought a revolution that changed civilisation for ever. Then came iron with its hard edge for swords and, later still, steel brought the Industrial Revolution. During the 20th century the pace quickened, in less than a hundred years several entirely new classes of material appeared and quite new ones will certainly make an impression on the 21st century.

Until recently, most new materials were discovered by complete accident, or by trial and error. The latter strategy involves taking a few metals, mixing them together in certain ratios and watching what comes out. The process of studying a material's behaviour under pressure, at high and low temperature, in and out of magnetic and electric fields and in countless other conditions can take years or decades.

But all this can soon change. Recent advances in mathematics and computing are making it possible to simulate the properties of materials. This approach entirely changes the whole idea of materials testing. What's more, the work that used to take years can now be done in months. The simulations begin with rules of quantum mechanics that govern matter on the atomic and subatomic level.

Huge increases in computing power have made the simulations possible and recent developments of mathematical methods are making complex calculations much easier. Thanks to new techniques of research the number of calculations needed to solve large numbers of functions has fallen.

Where the simulations work, they bring a great change to materials development. Thanks to this new simulation technology the 21st century will get new materials in quantities that had never been heard of before.

CUTTING FLUIDS

Coolants or cutting fluids are applied to reduce the heating of a tool and to prolong its life. Milling cutters are cooled with special cutting fluids. Cutting fluids should be supplied in a continuous stream and immediately that milling has begun.

Mist cooling is a recent development at the plants. For this purpose, the machine is equipped with a mixer filled with soluble oil. The mist prolongs tool life and enables the cutting speed to be increased.

MILLING MACHINE MAINTENANCE

The machine should always be free from dirt, dust, chips. Clean the machine while it stands idle. Dirt and oil are washed off with cotton waste dipped in kerosene. Then wipe off the machine with dry waste. Before off-days the whole machine should be coated with oil to prevent corrosion. After the machine has been cleaned, all used waste should be stowed in a special box.

 

II.Переведите на русский язык следующие английские словосочетания:

1) hard edge for swords 6) the whole idea of materials testing
2) new classes of material appeared 7) rules of quantum mechanics
3) by complete accident, or by trial 8) on the atomic and subatomic level
4) a material's behaviour 9) new simulation technology
5) advances in mathematics and computing 10) new materials in quantities

 

III.Найдите в тексте английские эквиваленты следующих словосочетаний:

1)изменило цивилизацию 6)может скоро измениться
2)недавнее развитие 7)работа, на которую обычно уходят годы
3)поведение материалов 8)бесчисленные другие условия
4)свойства материалов 9)большинство новых материалов
5)полностью меняет идею 10) благодаря новым технологиям

 



IV.Найдите в тексте слова, имеющие общий корень с данными словами. Определите, к какой части речи они относятся, и переведите их на русский язык:

Man, quick, impress, develop, research, behave, calculate, simulate, entire, industry.

 

V.Задайте к выделенному в тексте предложению все типы вопросов: общий, альтернативный, разделительный, два специальных: а) к подлежащему, б) к любому члену предложения.

VI.Выполните анализ данных предложений, обратив внимание на следующие грамматические явления: формы и функции причастия, независимый причастный оборот, формы и функции герундия, герундиальный оборот. инфинитивные конструкции (сложное дополнение, сложное подлежащее), существительное в роли определения, функции слов one (ones), that (those), условные предложения (сослагательное наклонение 1 и 2 типов):

  1. Recent advances in mathematics and computing are making it possible to simulate the properties of materials.
  2. The process of studying a material's behaviour under pressure can take years or decades.
  3. The scientists expected this approach to change the whole idea of materials testing.
  4. The developments of mathematical methods would make complex calculations much easier if huge increases in computing power made the simulations possible.
  5. The simulations having worked, they brought a great change to materials development.

 

 

VII.Ответьте на вопросы по тексту:

1. What happened when bronze arrived?

2. How were most new materials discovered?

3. What does the latter strategy involves?

4. What do recent advances in mathematics and computing make it possible to do?

5. What have huge increases in computing power made?

6. What are coolants or cutting fluids applied for?

7. When should you clean the machine?

 

VIII.Составьте аннотацию к тексту (2 - 3 предложения).

IX.Составьте реферат текста (10 - 15 предложений).

X. Составьте план текста и перескажите текст.

ВАРИАНТ № 8

I. Прочитайте и переведите тексты:

MACHINE-TOOLS

 

The machine-tool is the principal manufacturing equipment in a machine shop. It is essential in the manufacture of every product from a giant turbine to minute jewels for aircraft instruments.

One of the simplest tools is the ordinary drilling machine. It consists of a spindle which imparts rotary motion to the drilling tool, mechanism for feeding the tool into the work, a table on which the work rests, and a frame.

The drilling machines or drill presses are grouped into the following four classes: sensitive, upright, radial and multi-spindle machines.

A milling machine is a machine-tool that removes metal as the work is fed against a rotating cutter.

The lathe is a machine-tool which can perform a wide variety of operations. It is primarily used for turning and boring operations. In addition, the lathe can be used for drilling, reaming, tapping and, by employing suitable adapters, operations of milling and grinding may be carried out without difficulty.

The lathe is the oldest machine-tool, but it is still widely used.

There are many types of lathes that differ in their size, design, method of drive, arrangement of gears and purpose.

According to the character of work performed, the design and construction lathes are divided into the following types: bench lathes, chucking lathes and automatic lathes. There are also screw machines, boring mills, crankshaft lathes, wheel lathes, etc.

MEASURING TOOLS

Machined workpieces are measured by accurate measuring tools, such as precision vernier calipers, micrometer calipers, inside micrometers and limit gauges.

In performing accurate work a precision vernier caliper is required. The micrometer caliper, or simply micrometer, is used for more accurate measurements of external dimensions of work, such as diameters, thickness and lengths. Internal dimensions may be measured with an accuracy of 0.01 mm using inside micrometers.

The best measuring tools for checking threads are standard and limit thread gauges.

 

II.Переведите на русский язык следующие английские словосочетания:

 

1) giant turbine 6) is widely used
2) imparts rotary motion 7) differ in size
3) for feeding the tool 8) arrangement of gears
4) removes metal 9) the design and construction lathes
5) operations of milling and grinding 10) according to the character of work

 

 

III.Найдите в тексте английские эквиваленты следующих словосочетаний:

1) различаются по размеру 6) для подачи инструмента
2) операции фрезерования и шлифования 7) гигантская турбина
3) расположение шестерен 8) придает вращательное движение
4) широко используется 9)старейший станок
5) удаляет металл 10)следующие типы

IV.Найдите в тексте слова, имеющие общий корень с данными словами. Определите, к какой части речи они относятся, и переведите их на русский язык:

principe, manufacture, equip, air, simple, feed, drill, right, suit, arrange.





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