Учебное пособие Издание второе, переработанное и дополненное Москва Астрель act 2005
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Part IV. MODERN DISCOVERIES, THEORIES AND TECHNOLOGIES UNIT FOURTEEN GRAMMAR: МЕСТОИМЕНИЕ ONE Модальные глаголы must, have, should, ought, may, can, might теряют ciioи оттенки значений и переводятся практически одинаково. Местоимение one не переводится.
• Complete the sentences.
• Translate the following sentences. Pay special attention to: • one as the subject of a sentence. Model 1: One could expect the value to change. Можно было бы ожидать, что эта величина изменится.
• one as a substitute for a previously mentioned noun. Model 2: Have you developed any procedures? We need an effective one. Вы разработали какие-то процедуры? Нам нужна эффективная (процедура).
WORD AND PHRASE STUDY gain п. - усиление, коэффициент усиления v. - получать
READING (14A) • Read the passage attentively and be prepared to discuss its plot according to the following outline:
SUPERCONDUCTORS The Startling Breakthrough That Could Change Our World That discovery, most scientists believe, could lead to incredible savings in energy: trains that speed across the countryside at hundreds of miles per hour on a cushion of magnetism, practical electric cars, powerful yet smaller computers and particle accelerators, safer reactors operating on nuclear fusion rather than fission and a host of other rewards still undreamed of. Superconductivity is aptly named. It involves a remarkable transition that occurs in many metals when they arc cooled to temperatures within several degrees of absolute zero, or, as scientists prefer to designate it, 0 Kelvin. Absolute zero equivalent to —460°F or -273°C, represents a total absence of heat; it is the coldest temperature conceivable. As the metals approach this frigid limit, they suddenly lose all their electrical resistance and become superconductors. This enables them to carry currents without the loss of any energy and in some cases to generate immensely powerful magnetic fields. Scientists have recognized for years that the implications of this phenomenon could be enormous, but one stubborn obstacle has stood in their way: reaching and maintaining the temperatures necessary for superconductivity in these metals is difficult and in most instances prohibitively expensive. From the time that a Dutch physicist Kamerlingh Onnes discovered superconductivity in 1911 until the recent rush of breakthroughs, there was only one way to produce the phenomenon: by bathing the appropriate metals — and later, certain metallic alloys — in liquid helium. This exotic substance is produced by lowering the temperature of rare and costly helium gas to 4.2K (—452°F), at which point it liquefies. But the process is expensive and requires considerable energy. Furthermore, unless the liquid helium is tightly sealed in a heavily insulated container it quickly warms and vaporises away. Thus, the practical use of superconductors has been limited to a few devices — an experimental Japanese magnetically levitated train, a few giant particle accelerators and medicine's magneticresonancc imaging machines that operate with intense magnetic fields. But in the last few years physicists have stumbled on unusual cases of ceramic compounds that change everything. They also must be cooled to become superconductors but only to a temperature of 98 К (—283°F) and that suddenly brings superconductivity into the range ofthe practical: liquid helium can be replaced as a coolant by liquid nitrogen, which makes the transition from a gas at the easily produced temperature of 77 К (—320°F). Moreover, liquid nitrogen is cheaper than milk and so longlasting that scientists carry it around in ordinary thermos bottles. Also, the ceramics may be able to generate even more intense magnetic fields than metallic superconductors. Thus, if these new substances can be turned into practical devices — and most scientists believe they can — technology will be transformed. • For each word in column 1 find its synonymous phrase or word in column 11. Model: (in most) instances — in most cases I heavily (insulated) tightly (sealed) immensely (powerful fields) prohibitively (expensive) startling (breakthrough) incredible (savings) remarkable (transitions) (the coldest) conceivable (temperature) frigid (limit) stubborn (obstacle) II that can be imagined not easy to control or deal with exclusively, forbiddingly uncommon; of unusual quality intensely cold impossible to be believed surprising not leaky severely immeasurably • Match each word in column I with its antonymous phrase or word in column II. I II exotic cheap rare very common expensive easy to control or deal with safe dangerous stubborn usual or colourless • Look through the passage and fill in the blanks with the proper information.
• Look through the passage and answer the following questions.
CLASS WORK READING (14B) • Skim the passage carefully (3 min), define the main idea of the passage and give a headline to it. In terms of the social impact superconductivity could well be the breakthrough of the 1980s in the sense that the transistor was the breakthrough ofthe 1950s. Indeed, scientists hardly know where to start in describing the bonanza that superconductors could yield. Take the transmission of electricity, for example. As much as 20% ofthe energy sent through high-tension lines is now lost in the form of heat generated as the current encounters resistance in the copper wire. If the electricity could be sent through superconducting cable, however, not a kilowatt-second of energy would be lost, thus saving the utilities, and presumably consumers, billions of dollars. Furthermore, at least in theory, all of a large city's electrical energy needs could be supplied through a handful of underground cables. Elimination of heat caused by electrical resistance could have ^profound effect on the design and performance of computers. In their efforts to produce smaller and faster computers, designers try to cram more and more circuits into chips and ever more chips into a tiny space. But they are limited in their scaling down endeavors by heat: even the tiny currents in computer circuits generate enough cumulative heat to damage components if they are too tightly packed. Today's personal computers could not operate without vents or internal fans to dissipate the heat. Now, with practical superconducting circuitry on the horizon, computer designers may soon see the way clear for even more remarkable miniturization. In still othcrapplications, the intense magnetic fields that might some day be generated by the new superconductors should benefit any device that now uses electromagnctism in its operation — medical diagnostic imaging machines, magnetically levitated trains, fusion-energy generators — and will undoubtedely spawn a host of new machines. Electric motors could increase in power and shrink in size.
HOMEWORK (to be done in writing) 1. Translate into Russian. High-temperature Superconductors The new HTSCs arc mixed oxides that display the mechanical and physical properties of ceramics. A key to the behaviour of the new ..- 'crials appears to be the presence of planes containing copper (Cu) and • gen (O) atoms, chemically bonded to each other. The special nature of the copper-oxygen chemical bonding gives rise to materials that conduct electricity well in some directions in contrast to the majority of ceramics whic'i are electrically insulating. The first class of high T(.' oxides discovered was based on the chemical alteration ofthe insulating ternary compound La2Cu04 by replacement of a small fraction ofthe element lanthanum (La) with the alkaline earths barium (Ba), strontium (Sr) or calcium (Ca). This substitution led to compounds with Tcs of up to 40 K. In these materials, an intimate relation between superconductivity and magnetic order is presently under intensive study and has inspired one of the many classes of theories that attempt to explain HT Superconductivity. 2. Translate into English.
Tt.s — critical temperatures UNIT FIFTEEN GRAMMAR: REVISION • Provide answers to the following questions. Use the words in brackets. Follow the model. Model: What problems do they discuss? (A highly important...) A highly important problem has just been discussed by them.
• Translate into English using the Passive Voice. Follow the model. Model: Многие насущные (pressing) задачи нашего времени решаются в этом институте. Many ofthe pressing problems of our days are solved at this college. В нашем институте постоянно решаются жизненно важные (vital) проблемы. Выдвигаются интересные гипотезы. Рассматриваются различные пути исследования. Конструируются высокочувствительные (highly sensitive) приборы. Развиваются новые методы исследования. Изобретаются жизненно необходимые материалы. 115 WORD AND PHRASE STUDY followv. — следовать за; следовать чему-то, придерживаться чего-то followed by — за которым следует as follows — следующим образом be as follows — заключаться в следующем it follows that — из этого следует, что; следовательно in what follows — ниже, в дальнейшем (syn. in the following) following adj. — следующий prp. — следуя, вслед за, после; согласно, в соответствии с in the following way — следующим образом (syn. in such a manner, in this fashion, in this way) • Sentences to be translated.
READING (15A) • Read the passage carefully and find facts to prove or disprove the idea that scientists are close to comprehensive understanding of the superconductivity mechanism. STATUS OF THEORETICAL UNDERSTANDING While scientists know the chemical composition of the new class of superconductors, they are less certain about how they work. True, a theory exists that explains low-temperature superconductivity. It is known as BCS from the initials ofthe authors John Bardeen and his colleagues Leon Cooper and Robert Schrieffer, who shared the 1972 Nobel Prize for physics for their effort. In the microscopic theory of Bardccn-Coopcr-Schrieffer, the presence of a net attractive interaction between conduction electrons, which would normally repel each other because of their like electrical charges, is essential to the occurance of superconductivity. 1 n conventional superconductors this attraction originates in the dynamical motion ofthe crystal lattice which leads to unattractive "electron-photon-electron" interaction. But the recent appearance of superconductivity in a class of matcrialsquite different from the conventional superconductors, and with extremely high transition temperatures as well, has led physicists to explore a very wide spectrum of possible new pairing mechanisms involving, for example, spin fluctuations, acoustic plasmons and excitonic processes. The principle origin ofthe pairing "glue" remains an open and to some extent crucial question. There is a wide range of theoretical possibilities, and the ultimate explanation may involve a combination of mechanisms. Indeed, some theorists have discarded conventional BCS-theory and have suggested that there may not even be the traditional close relationship between energy gaps and basic superconducting properties. It may take a considerable effort to fully unravel the secrets of these compounds. Typical ofthe questions currently underactive consideration are the role played by oxygen, the nature and scope of dynamical mechanisms and resulting electron pairing, whether this coupling is weak or strong, and whether the anisotropic nature of the materials is a truly important feature. The appearance of superconducting coherence lengths one or two orders of magnitude smaller than those previously encountered, the very low carrier concentrations, and the apparent importance of both copper and oxygen will probably require a considerable extension of our current understanding of superconductivity. The fact that the superconducting interaction mechanism in the new materials is likely to be very different certainly enhances the prospect that other high-tempcrature superconducting materials (HTSC) may be discovered. • Look through the passage again and find English equivalents for the following Russian phrases. химический состав; менее уверены; суммарное взаимодействие притяжения; сходные заряды; существенно важнодля возникновения; притяжение зарождается; механизм образования пар; вопрос остается открытым и до некоторой степени критическим; окончательное объяснение; "развенчали" общепринятую теорию; энергетические зоны; полностью раскрыть секреты; усиливать перспективу того, что ...; значительное расширение нашего современного представления • Answer the following questions.
• Think and say a few words about:
CLASSWORK READING (15B) • Skim the passage (4 min), explain the title and answer the questions posed in the text. SUPERCONDUCTIVITY KEEPS SCIENTISTS ON THE BOIL In 1986, two researchers at IBM in Zurich, Switzerland, made what seemed a momentous discovery. An unusual kind of "pottery" (керамика) made from oxides of lanthanum, strontium and copper could conduct electricity without resistance at 30 degrees above absolute zero. In other words, the ceramic material was superconducting at 30 K. This temperature does not sound very high, but until then, physicists had seen superconductivity at temperatures only below 24 K. In fact, most physicists thought that superconductivity could not exist above 35 K. So, the two researchers, Georg Bednorz and Alex Miiller, were working in afield in which most people had given up hope of finding anything exciting. They even had to disguise their work from their supervisor in order to be able to do it. After Bednorz and Miiller announced their results, researchers around the world quickly confirmed the discovery. Within a few months, Paul Chu and his associates at the universities of Texas and Alabama found a new class of ceramics, made from oxides of yttrium, barium, copper and oxygen oxides, that became superconducting at an even higher temperature, 93 K. And that is when the excitement really began. It looked as though materials that were superconducting at room temperature were just around the corner, and the door was about to open on a golden era of physics, chemistry and technology. The programme forthe 1987 meeting of the American Physical Society in New York City had gone to bed in December before the discovery was widely known, so it contained nothing about high-temperature superconductivity. But the organisers ofthe meeting obligingly arranged for a special evening session on the topic just in case anyone had anything to contribute. Four thousand people attended. The session began at seven o'clock in the evening and finally broke up at six o'clock the following morning. The front page story of The New York Times called it the "Woodstock for physicists". The press heralded the high-temperature superconductors as the greatest discovery since the invention ofthe transistor. Pundits postulated that the materials would have far-reaching applications in power transmission, transport, energy storage and electronics. The economics of high-temperature superconductivity was set to change society. Why? Because although the lower temperature superconductors were already being used in specialized areas of science, they required liquid helium to keep them cool enough to remain superconducting. Cooling helium gas to below its boiling point of 4 К was expensive. The new superconducting oxides required only liquid nitrogen, which boils at 77 К to keep them working. It is much cheaper. Researchers also hoped that they would soon discover materials that were superconducting at room temperature. This would change the way we use energy and also speed up communications. A new technology would alter many aspects of our life. Virtually every major university, electronic and chemical company started research programs to examine the new compounds. Most technologically advanced countries started national initiatives. No country wished to be left behind in the race to exploit these new wonder materials. So, what has happened in the past years since then? Will these new superconducting materials fulfil their early promise? Or has the euphoria of an unexpected and remarkable discovery clouded the judgement of scientists, businessmen and politicians alike? (New Scientist, London, 15 July 1989)
• Match each word in column I with the one which means the opposite from column II. II attract, occurrence, different, enhance, presence, conduction, extremely, ultimate, initial, the same, repel, unimportant, disappearance, absence, weaken, slightly, insulation crucial • Choose the proper word and complete the sentences.
HOMEWORK (to be done in writing) 1. Translate into Russian. In 1987, each new report of achieving superconductivity at a higher temperature was received with excitement by the physics community. By summer, claimed records were approaching room temperatures, but enthusiasm was cooling. In December, signs of superconductivity above the boiling point of water (373 K) were reported. However, most observers were sceptical about this claim, reflecting growing doubts that the existence of superconductivity above 100 К has been proved. During the second half of the year, about 20 research groups reported evidence for superconductivity above 100 K. However, at the Boston meeting, Paul Chu, the researcher from the University of Houston, who made the first superconductor at 90 K, said higher-temperature observations were "unstable superconducting anomalies", rather than convincing results. He stressed that reports of high-temperature superconductivity should meet four criteria: zero resistance; demonstration of the Mcissner effect (the exclusion of magnetic fields from a superconductor); stability; and reproducibility. Although he said that there was "no clear evidence to exclude" the possibility of superconductivity well above 100 K, Chu believes that the highest reported temperatures for superconductivity which meet all four criteria are in the 90 to 100 К range. 2. Translate into English. Высокотемпературная сверхпроводимость Недавнее открытие (1986) сверхпроводимости при температурах до 95 К является одним из наиболее важных научных событий последующего десятилетия. Вероятно, наиболее примечательной особенностью этого открытия является то, что оно было совершенно неожиданным. Сверхпроводимость была открыта голландским (Dutch) ученым Камерлингом Оннесом (Kamerlingh Onnes) в 1911 году. Он обнаружил, что сопротивление замороженной ртути внезапно исчезало при 4,2 К (—269 градусов Цельсия), т.е. при температуре, которую можно получить (accessible) только погружением (immersion) в жидкий гелий. В 1913 году Оннес также обнаружил, что слабые магнитные поля разрушали этот эффект, и металл возвращался к своему обычному резистивному состоянию. Впоследствии было найдено, что другие металлы, такие, как олово (tin) и свинец (lead) являются сверхпроводниками при таких же низких температурах. Люди сразу же начали придумывать, как применить сверхпроводники (to invent applications for...), например, для уменьшения потерь на линиях электропередач (electric power systems). UNIT SIXTEEN GRAMMAR: THE COMPLEX OBJECT WITH THE INFINITIVE  Subject +Predicate believe expect consider assume, etc. sec hear observe feel, etc.
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