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How does laser light differ from ordinary light?
1. The waves of laser light are found to be coordinated in space and time and to have nearly the same length. 2. The light emitted by an ordinary source consists of uncoordinated waves of many different lengths. 3. Laser light is not so intense and coherent. 4. Laser light does not differ greatly from ordinary light.
Ex. 6. Remember the following antonyms: internal—external include—exclude direct—indirect dark – light purity – impurity Ex. 7. Form the derivatives from the following words: Differ, purity, use, develop, science, apply. Ex. 8. Give the missing forms of the following verbs: light – lighting find – found arise-arisen heat—heating show—showed
Ex. 9. Open the brackets translating the Ukrainian words into English: 1. The light emitted by an (звичайним) source consists of uncoordinated waves. 2. The scientists found the waves of laser (світла) to be coordinated in (просторі) and time. 3. Laser light is different from ordinary light even when it (просто) illuminates a surface. 4. (За допомогою) some instruments it is possible to examine materials andphysical phenomena in new ways. 5. (Внутрішня) structure should be examined much better.
Ex. 10. Insert prepositions or adverbs: 1. Laser light differs... ordinary light. 2. This difference results... the fact that this light is more intense. 3.... means... some microscopes we can observe the movement of these particles. 4. This material was examined... new ways. 5. He is working... the problem of using the source of light in industry. 6. Many new instruments and devices have been built.. this purpose lately. 7. This work consists... two parts, the first one having already been done.
The Objective Infinitive Construction
Ex. 11. Change the following sentences as in the models: M оd e 1 I: We expect that they will solve this problem very soon. We expect them to solve this problem very soon.
1. The scientists know that this phenomenon is important. 2. They suppose that she will take part in this work. 3. We consider that he knows the subject well. 4. Chemists know that isotopes find wide application both in industry and agriculture. 5. They expect the reaction will go to completion. 6. We think that he will help us in this work. 7. We consider that mercuric ions are colourless. 8. I want that he will leave for Kyiv tomorrow.
Model II: I thought that he had returned. I thought him to have returned.
1. We knew that the delegation had arrived. 2. They learned that he had carried out the experiment by the end ofthe week. 3. They expected that he had passed his last exam well. Ex. 12. Translate into English using the Objective Infinitive Construction: 1. Ми знаємо, що промінь лазера широко використовується у медицині. 2. Ми думаємо, що цей експеримент був проведено успішно. 3. Я припускаю, що джерело цього світла буде вивчено. 4. Я хочу, щоб ви взяли участь у цьому дослідженні. 5. Я бачу, як вони проводять досліди в нашій лабораторії. 6. Ми припускаємо, що конференція вже закінчилася. 7. Ми вважаємо, що ці легкі метали будуть використані у багатьох галузях промисловості у майбутньому.
Ex. 13. Translate the following sentences mind the Objective Infinitive Constructions: 1. The scientists stated atoms or molecules, which contain an even number of electrons to have no magnetic moment.2. They found that gas to be oxygen. 3. We supposed thissubstance to have liberated heat when the temperature had been greatly raised. 4. This scientist states laser light to bedifferent from ordinary light. 5. The scientists proved this substance to be an element. 6. After a number of tedious experiments, they made the substance dissolve. 7. Pressure caused ice to melt. 8. The scientists know many substances organic as well as inorganic to be stable in the presence of visible light.
Ex. 14. Translate the text, analyse the infinitives: How Light is Analysed The efforts of ancient philosophers to analyse matter begin with an understanding that matter can be separated into its elementary constituents. The concept that light can be analysed was much less obvious. We know men to have looked at rainbows without devising any kind of rational explanation for them. Even when Rene Descartes noted the colours of a rainbow to be like those produced by a prism he couldn't give an explanation to this phenomenon. It was Newton, who formulated the basic concept that light from ordinary sources is complex. By "complex" he meant that such light could be analysed into colours and the colours could be used to synthesize light.
Text B MACHINE-TOOLS VOCABULARY: Machine-tools – станки, workpiece – деталь, якуобробляють, facility – пристрій, thread(to) – різьба, нитка, нарізка, screw – винт, навинчувати, discharge– розряд, feed (fed, fed)– подавати, подача, lathe– токарнийстанок, friction– тертя, flexible– гнучкий, to mount– кріпити, прикріпляти, close tolerance – жорсткий допуск 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 mass-production 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 relatively to the workpiece. Most machining operations generate large amounts of heat, and cooling fluids (usually a mixture of water and oils) must be used 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 control of machine-tools and flexible manufacturing systems have made it possible for complete systems of machine-tools to be used flexibly 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 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. Ex. 15. Match the Words:
Ex. 16. Answer the questions: 1. What are machine-tools used for? 2. How are most machine-tools driven nowadays? 3. What facilities have all machine-tools? 4. How are the cutting tool and the workpiece cooled during machining? 5. What other machining methods have been developed lately? 6. What systems are used now for the manufacture of a range of products without the use of manual labour? 7. What parts can be made with lathes? 8. How can the cutting tool be moved on a lathe? 9. How is the workpiece clamped in a lathe? 10. Can we change the speeds of workpiece rotation in a lathe? 11. What is numerical control of machine tools used for?
Ex. 17. Find English equivalents in the text: 1. матеріал, що обробляють 2. електропривід 3. більш точний 4. окремі деталі 5. процес масового виробництва 6. пристосування для тримання різця і деталі 7. операції з механічної обробки деталі 8. високовольтний розряд 9. свердління ультразвуком 10. різання за допомогою лазерного променя 11. гнучкі виробничі системи 12. деталі круглі у розрізі 13. повертати деталь навколо її осі 14. рухати в бік, рухати у напрямку до деталі 15. глибина різання 16. безперервне обертання деталі 17. рухрізцявздовжстанини
Ex. 18. TranslateintoEnglish: 1. Токарний верстат дозволяє виробляти деталі круглі у розрізі. 2. Деталь затискається в патроні або на планшайбі токарного верстата. 3. Різець може рухатися як уздовж станини, так і під прямим кутом до неї. 4. Сучасні токарні верстати часто мають цифрове управління.
Unit 15
Text A MERCURY IN THE ENVIRONMENT Notes on the Text one part per million – одна частина на мільйон on a substantial scale – у великих масштабах toamountto – складати; дорівнювати; досягати Mercury is known to be a rare element. The element is found in trace amounts throughout the lithosphere (rocks and soil), the hydrosphere, the atmosphere and the biosphere (in tissues of plants and animals). In the rocks and soil mercury is found to be measured in fractions of one part per million. In the hydrosphere (the seas and fresh waters) it occurs only in parts per billion. In the atmosphere mercury is present both as vapour and in the form of particles. It should be noted, however, that under natural conditions the amount of mercury in the atmosphere is so smallthat extremely sensitive methods are required for detectingand measuring it. The situation is somewhat different in the biosphere. Plants and animals tend to concentrate mercury. For example, it has been found some marine algae to contain a concentration of mercury more than 100 times higher than thatin the seawater in which they live. Mercury today is used on a substantial scale in chemical industries, it being used in the manufacture of paints and paper as well as in agriculture. The world production of mercury has been found to amount to about 10,000 tons per year. In agriculture, mercury in the form of corrosive sublimate (HgCl2) can be used for disinfecting seeds. The chlorides of mercury are employed in protecting a number ofvegetable crops. Due to such large-scale uses a considerable amount of mercury waste is likely to flow into the air, the soil, the streams, rivers, lakes. One might ask whether all these may present a threat to health? In order to answer this question it is necessary to examine the forms in which mercury occurs. Liquid mercuryitself is not toxic to man, but mercury vapour, however,can be injurious. The soluble inorganic salts of mercury have long been known to be toxic. So, knowing properties and forms of mercury it is possible to use it. Mercury being very important, it is useful to continue investigating its properties very closely.
Properties of Mercury. Mercury is unusual in that it is the only metal, which is stable in the liquid state at about 20°C. It has a bright silvery luster, shows little tendency to tarnish at ordinary temperature, it being a good conductor of both heat and electricity. Because of its uniform expansion over a wide range of temperature, it is well adapted to use in thermometers, and due to its high density, low coefficient of expansion, and slight vapour pressure at ordinary temperature it is well suited for using in the liquid type barometer. Despite having high boiling point, mercury does show a small vapour pressure even at ordinary temperatures. Being raised to a temperature above its boiling point, mercury vapour readily conducts electricity at the same time emitting radiation, it being rich in ultraviolet rays.
Ex. 1. Answer the following questions: 1. Where can mercury be found? 2. What methods are required to detect the presence of mercury in the atmosphere? 3. Where is mercury used? 4. In what form is mercury used in agriculture? 5. What is mercury used for in agriculture? 6. Why is mercury considered to be unusual metal? 7. What properties of mercury do you know? 8. Why can mercury be used in thermometers and barometers? 9. When does mercury conduct electricity?
Ex. 2. Translate the following sentences paying attention to the word s in bold type; 1. By close study they could learn that the vapours of this substance are dangerous. 2. The similarity of mercury to zinc and cadmium is not very close, the metal showing a greater similarity to copper and silver. 3. Close the test tube until the solution cools. 4. The elements of Group II-B and IV -B of the Periodic System closely resemble the elements of Group III and IV respectively. 5. One degree is the one hundredth part of the temperature range between the normal freezing and boiling points of water. 6. The 6Li content of samples encountered in this laboratory has rangedfrom 4 to 98%. 7. The amount of water was not enough to carry out this experiment. 8. It should be noted that the increase in temperature amounted to only 20°C.
Ex.3. Explain the meaning of the verb "to do" in the following sentences: 1. The old methods of carrying out such experiments should be done away with. 2. What do you usually do in the laboratory? 3. He will do his best to finish his work in time. 4. Among the gases with which mercury does react is hydrogen sulphide. 5. Being lower than hydrogen in the activity series mercury does not displace hydrogen from solution but it does react with the oxidizing oxides to form their respective salts. 6. The substance does support combustion. 7. While no exchange takes place between chloride bromate and the corresponding halogen in neutral solutions exchange does occur if the solution is acidified. 8. Gold does not combine with oxygen or with sulphur and does not react with any familiar acids. It does, however, combine with chlorine and bromine. 9. Copper does not displace hydrogen from acids, but does react with acidic oxidizing agents. 10.They did carry out this work in due time. 11. Despite its high boiling point, mercury does show a small vapour fifessure even at ordinary temperature. 12. They did their task very well though it was rather difficult. 13. They always do everything in due time. 14. Do you know that a quite new property of this substance was observed? 15. I'll do my best to study well. Grammar   Что способствует осуществлению желаний? Стопроцентная, непоколебимая уверенность в своем...  Что вызывает тренды на фондовых и товарных рынках Объяснение теории грузового поезда Первые 17 лет моих рыночных исследований сводились к попыткам вычислить, когда этот...  ЧТО ПРОИСХОДИТ, КОГДА МЫ ССОРИМСЯ Не понимая различий, существующих между мужчинами и женщинами, очень легко довести дело до ссоры...  ЧТО И КАК ПИСАЛИ О МОДЕ В ЖУРНАЛАХ НАЧАЛА XX ВЕКА Первый номер журнала «Аполлон» за 1909 г. начинался, по сути, с программного заявления редакции журнала... Не нашли то, что искали? Воспользуйтесь поиском гугл на сайте:
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