Ползунова Обучение коммуникативному чтению 2015
.pdf9.Repairing the nuclear reactor is our … concern at the moment.
10.The surgeon’s medical … saved the man’s life.
11.Not all chemical substances are … .
12.How is the … of wood into ash explained?
¾ Reading 2
Nikolay Semyonov
Nikolay Semyonov, a physicist and chemist, and a leader of the Soviet nuclear weapons programme, was born on 15th April, 1896, and died on 25th September, 1986 in Moscow. His primary scientific contributions are related to the quantitative theory of chemical chain reactions, the theory of thermal explosion, and the burning of gaseous mixtures.
He was a Physics graduate of Petrograd (St Petersburg) University, and in 1920 he was put in charge of the electron phenomena laboratory of the Physico-Technical Institute in Petrograd. It was at this time, while working with Pyotr Kapitsa, that he discovered a way to measure the magnetic field of an atomic nucleus. In 1931, he became Director of the Institute of Chemical Physics of the USSR Academy of Sciences, and from 1944 he was a professor at the Moscow State University.
For his work on the mechanism of chemical transformation, he was awarded the 1956 Nobel Prize for Chemistry. Semyonov’s work on the mechanism of chemical transformation includes an important analysis of the application of the chain theory (a sequence of reactions where a reactive product or by-product causes additional reactions) to different reactions, particularly combustion processes.
In chemistry and physics, a chain reaction is a reaction that once, started, continues without further outside influence. Proper conditions for a chain reaction depend not only on various external factors, such as temperature, but also on the quantity and shape of the substance in the reaction. A chain reaction can be of various types, but nuclear chain reactions are the best known, and it was in this particular area that Semyonov contributed his expertise to the nuclear weapons programme. He also made valuable contributions to the field of molecular physics and electron phenomena.
Semyonov published his work in three important books. The first was Chemistry of Electron, published in 1927. This was followed by
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Chemical Kinetics and Chain Reactions in 1934, which was the first book in the USSR to propose a theory of chain reactions in chemistry. Further studies in chemical kinetics led to the publication, in 1954, of
Some Problems of Chemical Kinetics and Reactivity, which was translated into many languages.
Semyonov received many awards and honours in his lifetime, including five Orders of Lenin. He was a member of the Chemical Society in London, Foreign Member of the American, Indian, German, and Hungarian Academies of Sciences. He held honorary doctorates from the University of Oxford and Brussels University.
¾ F Comprehension
Read the text and choose the best title for each paragraph. There is one title which you do not need to use.
Paragraph 1. …
Paragraph 2. …
Paragraph 3. …
Paragraph 4. …
Paragraph 5. …
Paragraph 6. …
A.Scientific career
B.Lifetime recognition
C.Basic facts
D.Famous author
E.The highest honour
F.The combustion process
G.Explanation of a scientific process
¾ G Translation work. Explain the grammar of the sentences
1.Nikolay Semyonov was a Soviet physicist and chemist who, together with Sir Cyril Hinshelwood, was awarded the 1956 Nobel prize for Chemistry for research into chemical kinetics.
2.Semyonov had a successful career and became a Professor at the Moscow State University and the Director of the Institute of Chemical Physics of the USSR.
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3.Semyonov conducted research into the mechanisms of chemical chain reactions.
4.A chain reaction is a reaction that, once started, continues without further outside influence.
5.A chain reaction can be of various types, but nuclear chain reactions are the best known.
6.Semyonov contributed much to the study of chemical chain reactions, the theory of thermal explosions and the burning of gaseous mixtures.
7.Professor Semyonov received many awards and honours from foreign universities and scientific societies.
8.A chain reaction can be of various types, but nuclear chain reactions are the best known, and it was in this particular area that Semyonov contributed his expertise to the nuclear weapons programme.
Before you listen
Discuss these questions with your partner.
•How much do you know about atomic science?
•What do you think of it?
¾H Listening CD 1 (track 41)
Listen to a lecture on atomic and nuclear energy and keep notes. Then answer the questions with your own words.
1.Where is energy contained?
2.What is nuclear fission?
3.What is used to split an atom?
4.What is nuclear fusion?
5.When a uranium atom is split into two, what particles are released?
6.How could a nuclear winter affect life on Earth?
¾ I Speaking
Task
Discuss with your partner the dangers of nuclear war. Say what you think and find out if your partner agrees or disagrees with you.
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Talk about:
•the main idea behind nuclear energy
•nuclear fission
•nuclear fusion
•the future
Read texts 1 and 2 again and your notes from listening exercise
G.Use the following notes as well to help you.
The main idea: chemical kinetics and chain reactions Nuclear fusion: what happens?
The future: what might happen?
Remember to:
•try to use your own examples
•explain yourself clearly
•listen to your partner
¾J Writing
Write a report on the topic «Factors affecting chemical reaction rates».
Read texts 1 and 2 again and use these notes to write six sections. Use the title headings below for your sections. Use functional phrases of opinion giving, generalizing, ordering and summarizing:
I think/suppose, I know for sure, in my opinion, as a rule, for the most part, generally speaking, as a matter of fact, first of all, to begin with, another thing is, furthermore, moving on to, finally, in conclusion, to sum up. Write 200-300 words.
Report: Factors affecting reaction rates By: (Your name)
Date: (The date)
Introduction
Say what the report is about, and briefly list the areas you will discuss.
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Section 1
Concentration
Vocabulary: collide
Section 2
Pressure
Vocabulary: compress, force
Section 3
Surface area
Vocabulary: reaction rate, molecules
Section 4
Reactivity
Vocabulary: metals, consumed
Section 5
Temperature
Vocabulary: hot system, activation energy, bounce off
Section 6
Catalysts
Vocabulary: increase rate, minimum energy
Conclusion
Sum up by giving an outline of the six main areas.
¾ Reading Comprehension
Read several passages. Each passage is followed by a series of questions. For questions 1–3, you need to select the best answer, (A), (B), (C), or (D), to each question.
Questions 1 to 7 are based on the following passage.
A snowflake originates from countless water molecules that initially come together in small groups as a result of a weak attractive force between oxygen and hydrogen atoms. The same forces subsequently organize the groups into a frozen molecular crystal, a perfectly organized lattice molecules. Finally, several molecular crystals join to form a
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snowflake. Scientists have realized for some time the forces that assemble molecules into natural crystals can be utilized to produce a variety of important materials. They have determined the structure of more than 90,000 different molecular crystals, the most common examples of which are aspirin and mothballs.
In recent years, researchers have studied how molecules organize themselves to form crystals in the hope of better understanding what types of molecules and what conditions will produce molecular crystals with unusual and useful properties. Scientists are aware that the material properties of crystal depend in large part on the organization of the molecules in the crystal, yet they know little about the factors controlling the assembly of such crystals.
Synthesizing a molecular crystal is similar to designing a building. Before construction can begin, the architect must specify the shapes and sizes of the girders and the number and placement of the appropriate sizes and shapes and select the molecular forces that will hold the crystals together. A chemist can normally find many molecules of various shapes and sizes, but the challenge is to find ones that assemble in a predictable manner.
1. According to the passage, a snowflakes is formed by
A. the attractive force between oxygen and hydrogen B. molecular crystals with new and useful properties C. the synthesizing of molecular crystals
D. the joining of several molecular crystals
2. According to the passage, water molecules join together as a result of
A. an attraction between oxygen and hydrogen atoms B. the organization of the molecules in a crystal
C. a strong force that assembles crystal atoms
D. the unusual and useful properties of molecular crystals
3. By making use of forces that assemble molecules into natural crystals, scientists can
A.find molecules of various shapes and sizes
B.determine the structure of different molecular crystals
C.organize molecules into a perfect lattice
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D. create new and useful materials
4. According to the passage, what reason do researchers have for studying how molecules organize themselves to form crystals?
A. To assemble molecules into natural crystals B. To learn how to synthesize molecular crystals C. To make aspirin and mothballs
D. To change the material properties of a crystal
5. According to the passage, what do scientists still need to learn about the organization of molecules?
A. What determines the material property of a crystal B. The molecular forces that hold molecules together C. the conditions that produce molecular crystals
D. The factors controlling the way crystals are assembled
6. To produce new molecular crystals, chemists must choose all of the following EXEPT
A. molecules of the right size
B. molecules of the appropriate form C. the right molecular organization D. the proper molecular forces
7. According to the passage, the task of synthesizing a molecular crystal can be compared to
A.designing a building
B.building a house
C.making materials
D.constructing a lattice
Questions 8 to 16 are based on the following passage.
The cause of the tooth decay is acid, which is produced by bacteria in the mouth. The acid removes minerals from tooth enamel, allowing tooth decay to begin; the saliva in your mouth encourages remineralization and neutralizes the acid. The rate at which bacteria in the mouth produce acid depends on the amount of plaque on the teeth, the composition of the microbial flora, and whether the bacteria of the plaque have been «primed» by frequent exposure to sugar. To keep your
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teeth healthy, a regular dental hygiene program should be followed. Removing plaque with a toothbrush and dental floss temporally reduces the numbers bacteria in the mouth and thus reduces tooth decay. It also makes the surfaces of the teeth more accessible, enabling saliva to neutralize acid and remineralize lesions. If fluoride is present in drinking water when teeth are forming, some fluoride is incorporated into the enamel of the teeth, making them more resistant to attack by acid. Fluoride toothpaste seems to act in another way, by prompting the remineralization of early carious lesions.
In addition to a regular dental hygiene program, a good way to keep your teeth healthy is to reduce your intake of sweet food. The least cavi- ty-causing way to eat sweets is to have them with meals and not between. The number of times you eat sweets rather than total amounts determines how much harmful acid the bacteria in your saliva produce. But the amount of sweets influences the quality of your saliva. Avoid, if you can, sticky sweets that can stay in your mouth a ling time. Also try to brush and floss your teeth after eating sugary foods. Even rinsing your mouth with water is effective. Whenever possible, eat foods with fiber, such as raw carrot sticks, apples, celery sticks, etc., that scrape off plaque, acting as a toothbrush. Cavities can be greatly reduced if these rules are followed when eating sweets.
8. What does this passage mainly discuss?
A. Good nutrition
B.Food with fiber
C.Ways to keep your teeth healthy
D.Fluoridization and cavities
9.According to the passage, all of the following statements about plaque are true EXCEPT
A.It consists of acid producing bacteria
B.It is not affected by eating sweets
C.It can be removed from teeth by brushing
D.It reduces the positive effect of saliva
10.We can infer from the passage that one benefit of fluoride to healthy teeth is
A.It strengthens tooth enamel
B.It stimulates saliva production
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C.It makes teeth whiter
D.It is a replacement for brushing and flossing in dental care
11. The word «it» in line 9 refers to
A.dental floss
B.bacteria
C.removal of plaque
D.plaque
12. What can be concluded from the passage about sweets?
A.All sweets should be avoided
B.Sweets should be eaten with care
C.It is better to eat sweets a little at a time throughout the day
D.Sticky sweets are less harmful than other sweets.
13.The word «scrape off» in line 24 is closest in meaning to?
A. repel
B. rub together with C. remove
D. dissolve
14.It can be inferred from the passage that foods with fiber are
A. sugary B. expensive C. sticky
D. abrasive
15.According to the passage, the value of eating foods with fiber is that
A. they contain Vitamin A
B. they are less expensive than a toothbrush
C. they are able to remove the plaque from your teeth D. they contain no sugar
16.The author of the passage states that the amount of acid produced by the bacteria in your saliva increases
A. with the amount of sweets you eat
B. with the number of times you eat sweets C. if you eat sweets with your meals
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D. if you eat sticky sweets
Questions 17 to 26 are based on the following passage.
Most human diets contain between 10 and 15 per cent of their total calories as protein. The rest of the dietary energy comes from carbohydrates, fats and in some people, alcohol. The proportion of calories from fats varies from 10 per cent in poor communities to 40 per cent or more in rich communities.
In addition to providing energy, fats have several other functions in the body. The fat-soluble vitamins, A, D, E, and K, are dissolved in fats, as their name implies. Good sources of these vitamins have high oil or fat content, and the vitamins are stored in the body’s fatty tissues. In the diet, fats cause food to remain longer in the stomach, thus increasing the feeling of fullness for some time after a meal is eaten. Fats add variety taste, and texture to foods, which accounts for the popularity of fried foods. Fatty deposits in the body have an insulating and protective value. The curves of the human female body are due mostly to strategically located fat deposits.
Whether a certain amount of fat in the diet is essential to human health is not definitely known. When rats are fed a fat-free diet, their growth eventually ceases, their skin becomes inflamed and scaly, and their reproductive systems are damaged. Two fatty acids, linoleic and arachidonic acids prevent these abnormalities and hence are called essential fatty acids. They also are required by a number of other animals, but their roles in human beings are debatable. Most nutritionists consider linoleic fatty acid an essential nutrient for humans.
17. This passage probably appeared in which of the following?
A.A diet book
B.A book on basis nutrition
C.A cookbook
D.A popular women’s magazine
18. We can infer from the passage that all of the following statements about fats are true EXCEPT
A.fats provide energy for the body
B.economics influences the distribution of calorie intake
C.poor people eat more fatty foods
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