F Do microwaves cook food from the inside out? Some people think so, but the answer seems to be no. Microwaves cook food from the outside in, like conventional ovens. But the microwave energy only penetrates about an inch into the food. The heat that's created by the water molecules then penetrates deeper into the food, cooking it all the way through. This secondary cooking process is known as "conduction".
G When sales of microwave ovens took off in the late 1980s, millions of cooks discovered the same thing: Microwaves just don't cook some foods as well as regular ovens do. The reason: Because microwaves cook by exciting the water molecules in food, the food inside the microwave oven rarely cooks at temperature higher than 212°F, the temperature at which water turns to steam. Conventional ovens, on the other hand, cook to temperatures as high as 550°F. High temperatures are needed to caramelize sugars and break down proteins, carbohydrates and other substances, and combine them into more complex flavors. So, microwave oven can't do any of this, and it can't bake, either. Some people feel this is the microwave's Achilles heel. "The name 'microwave oven' is a misnomer," says Cindy Ayers, an executive with Campbell Soup. "It doesn't do what an oven does." "It's a glorified popcorn popper," says Tom Vierhile, a researcher with Marketing Intelligence, a newsletter that tracks microwave sales. "When the microwave first came out, people thought they had stumbled on nirvana. It's not the appliance the food industry thought it would be. It's a major disappointment." Adds one cooking critic: "Microwave sales are still strong, but time will tell whether they have a future in the American kitchen."
Questions 1 - 6
Reading Passage 1 has seven paragraphs A - G. State which paragraph discusses each of the points below. Write the appropriate letters A - G in boxes 1 - 6 on your answer sheet.
Examples The Discovery That Spencer Made
Answer B
1. The Introduction of the Radarange
2. The Conduction Process of Heating Food
3. Basic Cooking Method of Microwave oven
4. The Commercial Development of the Microwave
5. Popularity of Microwaves Today
6. Limitations of the Microwave
Questions 7 - 11
Complete the summary below with the word taken from each blank. Write your answers in boxes 7 - 11 in your answer sheet. Use NO MORE THAN ONE WORD for each blank.
Before magnetrons were used for microwaves they were primarily used (7) systems. Microwaves have much (8) wavelength than electromagnetic waves. Why do microwaves cook so fast? The reason that regular ovens cook so slowly is because ovens heat air molecules first, while microwaves heat (9) molecules first. Microwave ovens cook food in any direction because when the microwaves hits the metal walls in a microwave they (10) off the metal walls. The process that allows microwaves to cook food from the outside to the inside may best be called "heat transfer by (11) ."
Questions 12 - 15
Do the following statements agree with the information given in Reading Passage 1? Write your answers in boxes 12 - 15 on your answer sheet.
YES if the statement agrees with the information
NO if the statement contradicts the information
NOT GIVEN if there is no information on this in the passage
12. Spencer invented magnetrons.
13. Regular ovens are better at breaking down sugars because they heat them at a lower temperature.
14. Raytheon couldn't make money out of microwave ovens at first.
15. In the future, microwave sales are not likely to be as good as they were in the past.
练习一
Garbage In, Garbage Out
There are many ways of obtaining an understanding of people's behaviour. One of these is to study the objects discarded by a community, objects used in daily lives. The study of the refuse of a society is the basis for the science of archaeology in which the lives and behaviour of past societies are minutely examined. Some recent studies have indicated the degree to which rubbish is socially defined.
For several years the University of Arizona, USA, has been running a Garbage Project, in which garbage is collected, sorted out and noted. It began in 1973 with an arrangement whereby the City of Tucson collected for analysis garbage from randomly selected households in designated census collection districts. Since then the researchers have studied other cities, both in the USA and Mexico, refining their techniques and procedures in response to the challenges of validating and understanding the often unexpected results they have obtained. Garbage is sorted according to an extremely detailed schedule, a range of data for each item is recorded on a standardised coding form, and the researchers cross-tabulate their findings with information from census and other social surveys.
This Project arose out of courses designed to teach students at the University the principles of archaeological methodology and to sensitise them to the complex and frequently surprising links between cultural assumptions and physical realities. Often a considerable discrepancy exists between what people say they do or even think they do — and what they actually do. In one Garbage Project study, none of the Hispanic (Spanish-speaking) women in the sample admitted to using as much as a single serving of commercially-prepared baby food, clearly reflecting cultural expectations about proper mothering. Yet garbage from the Hispanic households with infants contained just as many baby food containers as garbage from non-Hispanic households with infants.
The Project leaders then decided to look not only at what was thrown away, but what happened to it after that. In many countries waste is disposed of in landfills; the rubbish is compacted and buried in the ground. So in 1987, the Project expanded its activities to include the excavation of landfills across the United States and Canada. Surprisingly, no one had ever attempted such excavations before.
The researchers discovered that far from being sites of chemical and biological activity, the interiors of waste landfills are rather inactive, with the possible exception of those established in swamps. Newspapers buried 20 or more years previously usually remained perfectly legible, and a remarkable amount of food wastes of similar age also remained intact.
While discarded household products such as paints, pesticides, cleaners and cosmetics result in a fair amount of hazardous substances being contained in municipal landfills, toxic leachates pose considerably less danger than people fear, provided that a landfill is properly sited and constructed. Garbage Project researchers have found that the leachates do not migrate far, and tend to get absorbed by the other materials in the immediate surrounds.
The composition of landfills is also strikingly different from what is commonly believed. In 1990 US survey people were asked whether particular items were a major cause of garbage problems. Disposable nappies (baby diapers) were identified as a major cause by 41 per cent of the survey respondents, plastic bottles by 29 per cent, all forms of paper by six per cent, and construction debris by zero per cent. Yet Garbage Project data shows that two per cent of the volume of landfills and plastic bottles less than one percent. On the other hand, over 40 per cent of the volume of landfills is composed of paper and around 12 per cent is construction debris.
Packaging — the paper and plastic wrapping around goods bought — has also been seen as a serious cause of pollution, But while some packaging is excessive, the Garbage Project researchers note that most manufacturers use as little as possible, because less is cheaper. They also point out that modern project packaging frequently functions to reduce the overall size of the solid-waste stream.
This apparent paradox is illustrated by the results of a comparison of garbage from a large and socially diverse sample of households in Mexico City with a similarly large and diverse sample in three United States cities. Even after correcting for differences in family size, US households generated far less garbage than the Mexican ones. Because they are much more dependent on processed and packaged foods than Mexican households, US households produce much less food debris. (And most of the leaves, husks, etc. that the US processor has removed from the food can be used in the manufacture of other products, rather than entering the waste stream as is the likely fate with fresh produce purchased by households.)
One criticism made of Western societies is that the people are wasteful, and throw things away while they are still useable. This, however, does not seem to be true. Garbage Project data showed that furniture and consumer appliances were entering the solid waste stream at a rate very much less than would be expected from production and service-life figures. So the researchers set up a study to track the fate of such items and thus gained an insight into the huge informal and commercial trade in used goods that rarely turns up in official calculations and statistics.
The Garbage Project's work shows how many misconceptions exist about garbage. The researchers are therefore critical of attempts to promote one type of waste management, such as source reduction or recycling, over others, such as incineration or landfilling. Each has its advantages and disadvantages, and what may be appropriate for one locality may not be appropriate for another.
Glossary
Leachate: water carrying impurities which has filtered through the soil
Questions 1 - 7
Complete the following notes using information from the passage. Write NO MORE THAN THREE WORDS OR A NUMBER in boxes 1 - 7 on your answer sheet.
The Garbage Project
• started in 1973
• organised by (Example) Answer: University of Arizona
• first studied garbage in the city of ________ (1) ________ since then has studied it in other cities in USA and ________ (2) ________
• method: garbage collected and sorted, the information noted on ________ (3) ________
• findings compared with ________ (4) ________ and other social surveys
• reason for the Project: show students the ________ (5) ________ of archaeological ________ (6) ________
• from 1987 Garbage Project studied ________ (7) ________ in USA and Canada
Questions 8 - 11
Complete the following sentences using information in the passage. Choose the appropriate phrase A - C from the list in the box and write its letter in boxes 8 -11 on your answer sheet. You may use any phrase more than once.
A more ... than
B less... than, fewer ... than
C as many ... as, as much ... as
8. Hispanic women used ________ baby food ________ they said they did.
9. After excavating landfills the Garbage Project researcher found that there were ________ plastic bottles ________ people thought.
10. Mexican families create ________ garbage ________ American families.
11. Consumer appliances are reused ________ ________ was officially predicted.
练习二
Keeping Cut Flowers
While everybody enjoys fresh cut flowers around their house, few people know how to keep them for as long as possible. This may be done by keeping in mind a few simple facts.
An important thing to remember about cut flowers is that they are sensitive to temperature. For example, studies have shown that cut carnations retain their freshness eight times longer when kept at 12℃ than when kept at 26℃. Keeping freshly harvested flowers at the right temperatures is probably the most important aspect of flower care.
Flowers are not intended by nature to live very long. Their biological purpose is simply to attract birds or insects, such as bees, for pollination. After that, they quickly wither and die. The process by which flowers consume oxygen and emit carbon dioxide, called respiration, generates the energy the flower needs to give the flower its shape and colour. The making of seeds also depends on this energy. While all living things respire, flowers have a high level of respiration. A result of all this respiration is heat, and for flowers, the level of heat relative to the mass of the flower is very high. Respiration also brings about the eventual death of the flower, thus the greater the level of respiration, the sooner the flower dies.
Questions 1 - 3
Complete the sentences below with words taken from Reading Passage 1. Use NO MORE THAN ONE WORD or NUMBER for each blank. Write your answers in boxes 1 - 3 on your answer sheet.
1. A difference of 14℃ can extend the life of carnations by up to ________ times.
2. ________ and ________ are two aspects of a flower's appearance that depend on respiration.
3. Respiration is also necessary for the flowers to produce ________.
练习三
With all the hundreds of plant species used for food by th Australian Aborigines, it is perhaps surprising that only one, the Queensland nut, has entered into commercial cultivation as a food plant. The reason for this probably does not lie with an intrinsic lack of potential in Australian flora, but rather with the lack of exploitation of this potential. In Europe and Asia, for example, the main food plants have had the benefit of many centuries of selection and hybridisation, which has led to the production of forms vastly superior to those in the wild. Before the Europeans came, the Aborigines practised no agriculture and so there was no opportunity for such improvement, either deliberate or unconscious, in the quality of the edible plants.
Since 1788, there has, of course, been opportunity for selection of Australian food plants which might have led to the production of varieties that were worth cultivating. But Australian plants have probably "missed the bus". Food plants from other regions were already so far in advance after a long tradition of cultivation that it seemed hardly worth starting work on Australian species. Undoubtedly, the native raspberry, for example, could, with suitable selection and breeding programs, be made to yield a high-class fruit; but Australians already enjoy good raspberries from other areas of the world and unless some dedicated amateur plant breeder takes up the task, the Australian raspberries are likely to remain unimproved.
And so, today, as the choice of which food plants to cultivate in Australia has been largely decided. and as there is little chance of being lost for long periods in the bush, our interest in the subject of Australian food plants tends to relate to natural history rather than to practical necessity.
Questions 1 - 3
Complete the partial summary below. Choose ONE or TWO words from the passage for each answer. Write your answers in boxes 1 - 3 on your answer sheet.
