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The making of glass is a very old industry--at least 4,500 years old. Glass has many extra

ordinary qualities and it is frequently being used in new ways.

One of the most interesting new uses for glass is in telephone communication. Scientists have developed glass fibers as thin as human hair, which are designed to can-y light signals. When the light reaches the other end, it is first changed into electrical signals, which are in turn converted into sound messages.

Called light wave communication, the new system was used successfully in an experiment in Chicago in 1997. During the experiment, two glass fibers were able to carry 672 conversations at the same time. The lightwave cable, containing 144 glass fibers, has the capacity to carry 50,000 conversations at the same time.

The lightwave communication system has two important advantages. First, the glass fiber cables are smaller and weigh less than copper. Second, they cost less.

Perhaps it can be said that telephone communication has entered the age of light.

One of the extraordinary qualities of glass is that it can carry ______.

A.sound signals

B.light signals

C.electrical signals

D.any signals

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更多“The making of glass is a very …”相关的问题
第1题
Artificial flowers are used for scientific as well as for decorative purposes. They are ma
de from a variety of materials, such as wax and glass, so skillfully that they can scarcely be distinguished from natural flowers. In making such models, painstaking skill and artistry are called for, as well as thorough knowledge of plant structure. The collection of glass flowers in the Botanical Museum of Harvard University is the most famous in North America and is widely known throughout the scientific world. In all, there are several thousand models in colored glass, the work of two artists-naturalists, Leopold Blaschka and his son Rudolph.

The intention was to have the collection represent at least one member of each flower family native to the United States. Although it was never completed, it contains more than seven hundred species representing 164 families of flowering plants, a group of fruits showing the effect of fungus diseases, and thousands of flower parts and magnified details. Every detail of these is accurately reproduced in color and structure. The models ate kept in locked cases, as they are too valuable and fragile for classroom use.

Which of the following is the best title for the passage?

A.An Extensive Collection of Glass Flowers.

B.The Live Leopold and Rudolph Blaschka.

C.Flowers Native to the United States.

D.Materials Used for Artificial Flowers.

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第2题
Directions: There are five reading passages in this part. Each passage is followed by five
questions. For each question there are four suggested answers marked A, B, C and D. Choose the best answer and blackening the corresponding letter on the answer sheet.

Passage One

Artificial flowers are used for scientific as well as for decorative purposes. They are made from a variety of materials, such as wax and glass, so skillfully that they can scarcely be distinguished from natural flowers. In making such models, painstaking skill and artistry are called for, as well as thorough knowledge of plant structure. The collection of glass flowers in the Botanical Museum of Harvard University is the most famous in North America and is widely known throughout the scientific world. In all, there are several thousand models in colored glass, the work of two artists-naturalists, Leopold Blaschka and his son Rudolph.

The intention was to have the collection represent at least one member of each flower family native to the United States. Although it was never completed, it contains more than seven hundred species representing 164 families of flowering plants, a group of fruits showing the effect of fungus diseases, and thousands of flower parts and magnified details. Every detail of these is accurately reproduced in color and structure. The models ate kept in locked cases, as they are too valuable and fragile for classroom use.

31. Which of the following is the best title for the passage?

A. An Extensive Collection of Glass Flowers.

B. The Live Leopold and Rudolph Blaschka.

C. Flowers Native to the United States.

D. Materials Used for Artificial Flowers.

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第3题
Anyone who has ridden on a railroad train knows how rapidly another train【36】by when it is
traveling in the【37】direction and conversely how it may look almost【38】when it is moving in the same direction.【39】a train at a station starts to move forward【40】gently that passengers feels no backward movement【41】.Then if they happened to【42】the window and see another train slide past on the next track, they have no way of knowing【43】train is in motion and which is at rest;【44】can they tell how fast either one is moving or in which direction The only way they can judge their【45】is by looking out the other side of the car for some fixed body of reference【46】the station platform. or a single fight. Newton was【47】these tricks of motion, only he thought in terms of ships. He knew that on a calm day at sea a sailor can shave himself or drink soup as【48】as when his ship is lying motionless in harbor. The water in his basin, the soup in his bowl, will remain【49】whether the ship is making five knots, 15 knots or 25 knots. So【50】he looks hard at the sea it will be【51】for him to know how fast his ship is moving or indeed if it is moving at all. Of course, if the sea should get rough or the ship changes course suddenly,【52】he will sense his state of motion. But even supposing that we have the idealized conditions of a glass calm sea and a silent ship, nothing that happens below decks -- no amount of observation or mechanical experiment performed inside the ship --will reveal its velocity through the sea. The physical【53】based on these facts was formulated by Newton in 1687."The motions of bodies included in a given space , he wrote, "are the same【54】themselves, whether that space is at rest or moves uniformly【55】in a straight line."

(66)

A.passes

B.goes

C.flashes

D.moves

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第4题
完成下列各选项 A A greenhouse is a building made of glass whi
ch is used for keeping plants warm when the outside temperature is how.In a similar way there are several gases in the atmosphere which trap(捕捉)the heat produced by the sun and prevent it from escaping.These gases are known as“greenhouse gases“,and the way in which they trap heat in the atmosphere is called the “greenhouse effect”.This is not simply air pollution.Most of the main greenhouse gases exist naturally in small amounts in our atmosphere.And without them earth would be 30 degrees colder and human life would not exist.In other words,the greenhouse effect is a natural course which is to some degree helpful to us. The problem is that in the last century and a half.we have been putting too many 0f these gases into the earth’s atmosphere by burning large quantities of coal and oil and by cutting down forests.The rapid increase in greenhouse gases is making the world warmer.The world's temperature has already gone up by half a degree this century,and the sea level has risen by lo centi-metres.If the amount of carbon dioxide(二氧化碳)in the atmosphere doubles,there will probably be a rise in the earth’s temperature of between l and 4 degrees.This may seem a small in—crease,but it would be enough to cause major changes in geography and agriculture.Large areas of the world would be flooded.and some areas would become dry and unable to produce crops.It is important,too,to consider that there may be a delay of about 30 years in the greenhouse effect.This means that we’re probably experiencing only now the effect of the gases put into the atmosphere before the l960s.Since then,our use of these gases has greatly increased. “Greenhouse effect”means________.

A.a natural course which is to some degree helpful to us

B.the way.in which gases are used for keeping plants warm

C.the way“greenhouse gases”trap heat on the earth

D.the whole course in which greenhouse gases prevent heat

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第5题
阅读:Designing a lens can be compared to playing chess. In chess a player tries to trap his opponent's

Questions 31 to 35 are based on the following passage:

Designing a lens can be compared to playing chess. In chess a player tries to trap his opponent's king in a series of moves. In creating a lens a lens designer attempts to “trap” light by forcing all the rays arising from a single point in the subject to focus on a single point in the image, as a consequence of their passing through a series of transparent(透明的) elements with precisely curved surfaces. Since in both cases the ultimate goal and the means by which it can be attained are known, one is tempted to think there will be a single best decision at any point along the way. The number of possible consequences flowing from any one decision is so large, however, as to bevirtually, if not actually, infinite. Therefore in lens design, as inchess, perfect solutions to a problem are beyond reach. Although this article will be concerned only with the design of photographic lenses, the same principles apply to all lenses.

The lens designer has one enormous advantage over the chess player: the designer is free to call on any available source of help to guide him through the staggering number of possibilities. Most of that help once came from mathematics and physics, but recently computer technology, information theory,chemistry, industrial engineering and psychophysics have all contributed to making the lens designer's job immeasurably more productive. Some of the lenses on the market today were inconceivable a decade ago. Others whose design is as much as a century old can now be mass produced at low cost. With the development of automatic production methods, lenses are made by the millions, both out of glass and out of plastics. Today's lenses are better than the best lenses used by the great photographers of the past.Moreover, their price may lower, in spite of the fact that 19th century craftsmen worked for only a few dollars a week and today's lenses are more complex. The lens designer cannot fail to be grateful for the science and technology that have made his work easier and his creations more widely available, but he is also humbled: it is no longer practical for a fine photographic lens to be designed from beginning to end by a single human mind.

31.Lens design and chess playing are similar in that ____.

A) the final goal and the means by which it can be reached are known

B) perfect solutions to a problem can be found

C) any one decision at any point along the way to the goal can bring numerous possible results

D) both A and C

32.The final goal of designing a lens is ____.

A) to trap the opponent's lenses

B) to focus light with lenses

C) to hand make lenses at low cost

D) to reflect light by means of curved surfaces

33.After the passage the author will talk about ____.

A) the principles of designing lenses

B) techniques of making contact lenses

C) the design of photographic lenses

D) styles of lenses

34.Which of the following words cannot be used to describe today's lenses?

A) More delicate. B) Cheaper. C) Numerous. D) Unpopular.

35.Lens designers today ____.

A) have a large source of help to fall back on B) receive a low salary

C) are less respectable than those of the past D) are not decisive in the lens design

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第6题
下列哪个选项可以为照片添加玻璃浮雕效果()。

A.Glass Distortion(玻璃扭曲)效果

B.Glass Distortion(玻璃扭曲)动态层

C.Glass Distortion(玻璃扭曲)画笔

D.Glass Distortion(玻璃扭曲)图层

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第7题
glass()

A.眼镜

B.草

C.玻璃杯

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第8题
a glass of…()

A.太阳镜

B.一杯…

C.一堆

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第9题
-------------()

A.glass

B.weight

C.water

D.height

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第10题
I am in__2()

A.glass

B.grass

C.lass

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