English Reader for Technical Students. Учебное пособие

• Problem to discuss

What do you think of an all-plastic car? Can it become a reality? If so, what its advantages and disadvantages will be?

3.2. Libraries into space

Unbelievable though it sounds, we may have to place whole libraries in а space-like environment over the next decade! This strange proposal is not made because our orbiting astronauts need more reading material, but because if we don't do that most of our books won't be around very long for the rest of us to read. An alarming and little known problem faces mankind today – the vast majority of books, those printed since the 1850s, are relentlessly yellowing and crumbling to dust:

The library at the University of California at Berkeley in the USA, alone stands to lose 80,000 books and periodicals per year to decomposition. This is not because of air pollution; the source of the destruction lies in the very paper on which the books are printed. Now, some clever chemists have discovered that, surprisingly, а trip into an environment similar to space provides at least one solution to this vexing problem.

Papermaking processes used since the 1850s universally employ an alumrosin sizing to keep ink from feathering or spreading on the paper. Slowly, this papermaker's аlum-aluminium sulphate-combines with moisture in the pages and in the air to form sulphuric асid. This aggressive substance, in turn, facilitates attack on the cellulose fibres in the paper, breaking them into smaller and smaller fragments and, ultimately, to dust. Between 75 and 95 percent of the deterioration in 'modern' paper is caused by such acid attack.

In recent years, chemists have developed а number of acid-neutralizing processes for books. One process developed in the research laboratory of the Library of Congress in the USА suggests that а chemical, diethyl zinc, may be ideal for the job. Diethyl zinc is а gas, so its molecules can easily permeate even а closed book. Once inside, the substance deacidifies each book and then looks ahead to the future by leaving an alkaline residue zinc оху-саrbonate. The residue, uniformly distributed throughout the paper fibres protects the book from any future acid attack.

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However, diethyl zinc bursts into flame on contact with air and explodes when it touches water. How does а chemist work with а compound that cannot be exposed to air or water? In а deep space environment, or course. А suitable location was found at NASA's Goddard Flight Center, where 5000 books from the Library of Congress took а simulated flight, not on а rocket into space, but in a laboratory space-simulating vacuum chamber.

First, the books were thoroughly dried by warming under vacuum for 3 days. Then with all охуgen removed from the chamber, gaseous diethyl zinc was introduced and allowed to diffuse into the books. As the neutralizing reaction proceeded, harmless ethane gas was produced and pumped away. Then the protective zinc оху-carbonate is formed. The results have been extremely promising, and as the technology is perfected, libraries across the USА will be looking to install huge deacidification facilities. These countermeasures, coupled with the new ‘alkaline reserve’ papers now used in modern printing, promise that the precious heritage of the world's libraries will be preserved for future generations to enjoy, and profit from, just as we do today.

Notes on the text: relentlessly – неизбежно

crumble to dust – превращаться в пыль alumrosin sizing – квасцовое проклеивание alkaline residue – остаток щелочи oxy-carbonate – окись карбоната.

• Comprehension

For questions 1 – 6 choose the answer (a, b, c or d) which you think fits best according to the text.

1.There has been made a proposal to plane whole libraries into a spacelike environment because …

a.there is more place in libraries to store such a great number of books

b.orbiting astronauts need more reading material

c.old books are being gradually destroyed

d.scientists are experimenting with books to produce a new kind of paper.

2.Old books are relentlessly decomposed because …

a.the Earth’s atmosphere has become very polluted

b.the method of printing isn’t good enough

c.the conditions of the storage are not suitable

d.the source of the destruction lies in the very paper on which the books are printed.

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3.The source of the destruction is …

a.metal which printing material consist of

b.moisture and air

c.sulphonic acid

d.sulphuric acid.

4.Diethyl zinc is an ideal acid-neutralizing substance because …

a.its molecules can easily penetrate even a closed book

b.it’s very cheap

c.it’s freely available

d.it’s easy to be produced

5.Diethyl zinc cannot be widely used because …

a.it’s highly poisonous

b.not all kinds of paper can be influenced by this substance

c.It bursts into flame on contact with air and explodes when it touches water

d.the technology of its production is extremely complicated.

6.The results of the experiment are …

a.unrealistic

b.doubtful

c.kept secret

d.promising.

• Vocabulary

Find words or expressions in the article which mean:

extremely surprising; to put smth. somewhere; air, water, land in which people, animals and plants live; a period of ten years; most of books; continuing without stopping; to break apart into little pieces; to decay, to find out; empty of all gases; a complicated problem.

• Speaking

1. Describe the acid neutralizing process for books. Use the following expressions:

−to dry by warming under vacuum

−to remove oxygen

−to introduce gasous diethyl zinc

−to diffuse into books

−neutralizing reaction

−to produce harmless ethane gas

−to form the protective zinc oxy-carbonate.

2. Make a summary of the text.

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• Problem to discuss:

What do you think of the proposed method? What advantages and disadvantages can you see in it?

3.3. A lithium-powered heart

The heart pacemaker is a miracle of modern science that many of us take for granted – but not a person who owns one! Pacemakers operate on battery power, and the demands put on the tiny batteries generating the power are enormous. These batteries must keep the human lights and ratio running all the time and start the human

machine every morning without fail. Yet any people are adding healthy years to their lives by depending on the chemical reactions that occur in these batteries to generate – day in, day out – the electric current that drives their pacemakers.

These batteries have special requirements because they must be implanted in a human body. They must be rugged and leakproof, have long life and minimal weight, and, of course, they must be nontoxic. The first batteries used in pacemakers had a lifespan of only 2 years, and the periodic operations required for the replacement meant additional risk and stress for the patien

Chemists began to tackle the problem, and research efforts in electrochemistry indicated that lithium metal might be used to give longer life to batteries. Unfortunately, lithium is highly reactive – it burns in air, and it reacts with water to produce flammable hydrogen gas. If lithium were to be used, it would be necessary to discover new, nonaqueous electrolyte systems.

Electrolytes are substances that dissolve in water to form conducting solutions. They dissolve to produce ions, particles carrying electrical charge. The movement of these charges carries the current as the battery’s chemistry releases its stored energy. Conventional batteries that draw on the chemical energy of zinc and mercuric oxide depend upon aqueous electrolytes. The problem for the chemists to solve was – to design a lithium battery that would operate without water.

Extensive investigations, into new solvents and new materials for use in high energy, long-life batteries, eventually led to the discovery of a solid electrolyte for use with lithium metal. The solid electrolyte is iodine, and the lithium-iodine battery was born for biomedical applications. These

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revolutionary batteries are currently in use, and they have an impressive lifespan of 10 years. The benefits to those who must depend upon cardiac pacemakers are incalculable.

The lithium-iodine battery is not the end of the story While it is a vast improvement over its predecessors and extremely useful in pacemakers, it has a lower power than would be optimum for other uses. On the horizon is the need for new, higher-power batteries for use in other implantable organs like artificial kidneys and hearts. But further electrochemical research will undoubtedly provide the answer.

Notes on the text:

to take for granted – считать само собой разумеющимся

to put on demands on smth. – предъявлять требования к чему-то rugged – неровный, шероховатый

leakproof – герметичный flammable – воспламеняющийся solvent – растворитель

lifespan – срок действия

artificial kidney – искусственная почка.

• Comprehension

For questions 1 – 8 choose the answer (a, b or c) which you think fits best to the text.

1.Heart pacemakers operate …

a.from electrical devices

b.on battery power

c.from other organs of the body.

2.The chemical reactions that occur in the battery …

a.are of minor importance

b.no chemical reactions take place there

c.are very important for the battery to work successfully.

3.Heart pacemakers …

a.are implanted in the body

b.are carried by the patients in their pockets

c.can operate at a distance.

4.The first batteries were not very successful because …

a.they were toxic

b.their lifespan was very short

c.they were made of the wrong material.

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5.Why is lithium metal so good?

a.It is light

b.It is cheap

c.It gives longer life to batteries.

6.Lithium batteries can be used if …

a.they operate without water

b.we use a certain amount of lithium

c.lithium is combined with zinc.

7.The revolutionary batteries …

a.are going to be used in the nearest future

b.are currently in use

c.have already been used by our predecessors.

8.The lifespan of a new battery is …

a.two years

b.more than ten years

c.ten years.

• Vocabulary

The words in this table are from the article. Fill as many of the gaps as you can with related words.

• Speaking

−What are the demands put on heart pacemakers?

−Describe the work of electrolytes and say how important they are to heart pacemakers.

−Speak of the advantages and disadvantages of the lithium batteries.

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• Problem to discuss:

Do you think the lithium-iodine battery is the end of the story? What other discoveries are possible in the nearest future?

3.4. Experiments in time reversal

Today we have come to realize that the laws of nature are not indifferent to right and left, and we now suspect that they also make a distinction between past and future. As a result of recent findings in elementaryparticle physics the principle of the symmetry of the flow of time has been seriously challenged. An intense search is now under way to see if violations of the principle can be detected experimentally. Workers in the fields of atomic, nuclear and high-energy physics have undertaken a multipronged attack on the problem. No violation has yet been confirmed, but there is good reason to believe an asymmetry exists. It may be very small and difficult to detect, or perhaps we have not yet looked in the right places.

As an example of how physical laws remain unchanged in spite of reversal of the direction of time, consider celestial mechanics. Imagine that the direction of orbital motion and the direction of spin of all the bodies in the solar system have suddenly been reversed. Now leave them free to move under their mutual gravitational attraction. Time-reversal invariance tells us that the bodies will evolve in time backward through exactly the same orbits they have just traversed. The equations of physics do not prefer one direction of planetary motion over its opposite. The-planets are moving in one direction around the sun only because they somehow got started in that direction.

Another traditional example is found in the collision of billiard balls. Let a motion picture be taken of a series of elastic collisions of several billiard balls. On showing the film the projectionist gets confused and runs the film backward. Because the elastic collisions of the balls are invariant under time reversal, either a backward or a forward viewing corresponds to situations that can be physically realized; we in the audience cannot tell in which temporal direction the film sequence was actually shot. This same time symmetry has been found to be true for all known laws of physics, the classical Newtonian ones as well as those of modern quantum mechanics. On the other hand, almost everything we experience in the everyday world is strongly asymmetrical in time. It is absurd for us to

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conceive of our world as suddenly running backward. The world around us is ''most certainly evolving in one particular direction of time. We can understand this apparent paradox by focusing our attention on the complexity of the process being considered. In a sufficiently complex event, for example a physical reaction involving a large number of particles, we find that a definite directionality of time flow is, generally observed. Conversely, when we focus on elementary interactions between a few particles, this directionality is lost. The principle is the one contained in the second law of thermodynamics, which states that ordered systems tend to evolve in such a way as to increase their degree of disorder, or randomness. The evolution toward increasing randomness defines the direction of time. The time-reversed world is not impossible, just highly importable.

Notes on the text:

time reversal – изменение направления хода времени violations of the principle – нарушение принципа

time-reversal invariance – инвариантность относительно обращения времени

to involve – включать в себя to evolve – эволюционировать

to conceive – понимать, представлять себе.

• Comprehension

Give answers to the following questions:

1.Why have rigorous tests been made of nature’s indifference to which way time flows?

2.Why has the principle of the symmetry of the flow of time been seriously challenged?

3.Why did the question of the violation of time-reversal invariance arise in the first place?

4.What role do the concept of time-reversal and similar symmetry principles play in physics?

5.Why are the planets moving in one direction around the sun?

6.Why is it absurd for us to conceive of our world as suddenly running backward?

7.What defines the direction of time?

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• Vocabulary

1. The words in this table are from the article. Fill as any of the gaps as you can with related words.

2.Arrange the words given in a) and b) in pairs of synonyms.

a)to prove, rigorous, to suspect, to search, to violate, to participate, to order, to traverse, preferable, confusion, to forbid, to advise, to inquire, famous, to appreciate, eventual.

b)to prohibit, to think that something is true, to veriby, to cross, to command, to ask, desirable, to seek, to break, to recommend, to take part, disorder, celebrated, to value, final.

•Problem to discuss:

Recent findings indicate that the universe we know may be only half of

all that exists. There may be a complete set of antiworlds, which are possibly populated by thinking creatures? What do you think about it?

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CHAPTER 4. METALLURGY SYSTEMS AND

TECHNOLOGIES

4.1. Furnace design and operation

The task of designing and analyzing industrial furnaces is complex and time-consuming. Most furnaces are not mass-produced but built to specification. During the proposal phase of furnace buying, the customer’s needs are communicated to the furnace manufacturer, who in turn, comes up with several design solutions to satisfy these requirements. This process usually involves several iterations of lengthy engineering calculations.

One of the key aspects of furnace sizing and design is the need to understand the heat transfer among furnace walls, furnace atmosphere, and the parts being heat treated. It's well-known that heat flows from higher temperatures to lower temperatures, and that heat transfer takes place by radiation, convection, and heat flux. However, determination of each of these heat transfer components involves complex calculations. For example, at high temperatures, heat transfer takes place by radiation. Unfortunately, it is not a linear function. Moreover, thermophysical properties change with temperature. Engineers and designers use rules of thumb and manual calculations to "solve" these complex problems. Some may even use a computer spreadsheet program. The fact is that meaningful solutions to these problems cannot be obtained by manual or simple spreadsheet means.

The same argument applies to furnace users. Process engineers and heat treaters are always faced with the challenge of operating their furnaces at the highest efficiency without sacrificing product quality.

Thanks to advances in computer technology, the barriers formerly posed by these challenges have been leveled. More and more engineers are now using software tools for accurate analysis and simulation of equipment and processes. Moreover, the software provides a window on the process, enabling engineers to better understand what happens inside the parts as they are heat treated.

Furnace manufacturers can use the FurnXpert program to accurately and efficiently size furnaces for their customers, while heat treaters, process engineers, and plant operators can use the design and analysis software to determine the best setup for any furnace/part combination.

To help illustrate the benefits of design software, an analysis of a furnace was performed first using manual calculations and then using FumXpert software. The results were then compared. Although FumXpert software can be used to analyze any type of batch or continuous furnace, the subject of this study was a continuous mesh-belt furnace for sintering

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