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[单选题]

Which air is used to feed the HPTACC system（）

A.Fan air

B.HP compressor 5th stage air

C.HP compressor 4th and 9th stage air

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更多“Which air is used to feed the …”相关的问题

第1题

Which of the fluids listed is normally used to condense the primary refrigerant in a shipb

oard central air conditioning system？

A.Air or Nitrogen

B.Seawater or Fresh water

C.Sodium Nitrate brine

D.Calcium Sulfate brine

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第2题

People often speak of fire as though it were a living creature--It grows, dances, needs ox

ygen, feeds on whatever it can find, and then dies. And when a forest fire rages out of control, threatening human lives and homes, it must be fought like a "wild animal." The fight is often desperate, since firefighters' best efforts may be dwarfed by the fury of a large fire. But the fire's own traits can be used against it.

The heated air above a fire rises in a pillar of smoke and burnt gases, pulling fresh air in from the sides to replace it. Firefighters use this fact when they "fight fire with fire." They start a fire well in front of the one which they are fighting. Instead of traveling on in front of the huge fire, the smaller fire is pulled back toward it by the updrafts of the larger blaze. As it travels back to meet the large fire, the smaller backfire burns away the fuel that the forest fire needs to survive.

Even when a backfire has been well set, however, the fire may still win the struggle. The wind which the firefighters used to help them may now become their enemy. When the backfire meets the main fire, before both die for lack of fuel, there is tremendous flame, great heat and wild winds. A strong gust may blow the fire into the treetops beyond the area, giving the fire new fuel and a new life.

This passage focuses on ______.

A．how fires start

B．damage caused by fire

C．the fascination of fire

D．fighting forest fires

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第3题

Our environment is getting worse and worse with the increase of the world population, whic

h affects the environment in two ways. Firstly, the limited energy resources will be used up much faster. Secondly, the increasing population creates more pollution, another severe problem that needs to be solved: Both problems are long-term ones because actions taken now show their results slowly over many years. They are also urgent because delays in action can lead to great suffering and social problems. The question seems to be difficult to handle for most people. However, a person can be a protector of environment in everyday life if he takes actions to save the environment right now. With the development of technology, cars make transportation easier and quicker than before, but we can't ignore the disadvantages brought to us by more and more cars in use. For example, we are consuming gasoline(汽油), which is a non-renewable (无法更新的)resource, and will soon be gone. Moreover, the exhausted gas from cars pollutes our air, and our health is therefore threatened by air pollution, which has a big potential effect on our daily life. So we can consider walking, taking buses, carpooling(合用汽车) instead of driving cars alone. This seems to be a very slow process that can't be so effective if it's taken by a single person. But when more and more people become aware of the importance and positively take it as their personal responsibilities, the condition of the air will be improved to a great extent.

According to the writer, the main problem to our environment today is______.

A．the increase of population

B．the limited energy resources

C．the more serious air pollution

D．the development of technology

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第4题

根据材料回答下列各题,Smoking, which may be a pleasure for some people, is a serious source

of discomfort for their fellows. _51_, medical authorities express their concern about the effect of smoking _52_ the health not only of those who smoke but also of those who do not. In fact, non-smokers who must involuntarily inhale (吸入) the air _53_ by tobacco smoke may suffer more than the smokers _54_. Smoking is prohibited in the theatres and in halls used for showing films _55_ in laboratories _56_ there may be a fire hazard (危险). Elsewhere, it is up to your good _57_. I am _58_ asking you to maintain “No-Smoking” in classrooms and seminar rooms. This will prove that you have the _59_ health in mind, which is very important to a large _60_ of our students.

A.Still

B.Further

C.More

D.Again

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第5题

Smoking, which may be a pleasure for some people, is a serious source of discomfort for th

eir fellows. Medical authorities express their【31】about the effect of smoking on the health not only【32】those who smoke but also of those who do not. In fact, nonsmokers who must involuntarily inhale the air polluted by the tobacco smoke may【33】more than the smokers themselves.

As you are doubtless aware, a considerable number of our students have【34】an effort to【35】the university to ban smoking in the classrooms. I believe they are entirely right in their aim.【36】, I would hope that it is possible to achieve this by【37】on the smokers to use good judgment and show concern for others rather than【38】regulation.

Smoking is prohibited by city laws in theaters and in halls used for showing films as well as in laboratories【39】there may be a fire hazard. Elsewhere, it is up to your good sense.

I am therefore asking you to maintain "No Smoking" in the auditoriums and classrooms. This will prove that you have to keep nonsmokers' health and well-being【40】, which is very important to a large number of our students.

(31)

A．concern

B．trouble

C．interest

D．displeasure

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第6题

Foreachblankinthefollowingpassage,therearefourchoicesgivenbelowandmarkedA,B,CandD.Choose

For each blank in the following passage, there are four choices given below and marked A, B, C and D. Choose

the one that is most suitable and mark your answer by blackening the corresponding letter on the Answer Sheet.

Smoking, which may be a pleasure for some people, is a serious source of discomfort for their fellows. _51_,

medical authorities express their concern about the effect of smoking _52_ the health not only of those who

smoke but also of those who do not. In fact, non-smokers who must involuntarily inhale (吸入) the air _53_

by tobacco smoke may suffer more than the smokers _54_.

Smoking is prohibited in the theatres and in halls used for showing films _55_ in laboratories _56_ there

may be a fire hazard (危险). Elsewhere, it is up to your good _57_.

I am _58_ asking you to maintain “No-Smoking” in classrooms and seminar rooms.

This will prove that you have the _59_ health in mind, which is very important to a large _60_ of

our students.

__________

A. Still

B. Further

C. More

D. Again

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第7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8题

Green-space facilities are contributing to an important extent to the quality of the urban

environment. Fortunately it is no longer necessary that every lecture or every book about this subject has to start with the proof of this idea. At present it is generally accepted, although more as a self-evident statement than on the base of a closely-reasoned scientific proof. The recognition of the importance of green-spaces in the urban environment is a first step on the right way, this does mean, however, that sufficient details are known about the functions of green-space in towns and about the way in which the inhabitants are using these spaces. As to this rather complex subject I shall, within the scope of this lecture, enter into one aspect only, namely the recreative function of green-space facilities.

The theoretical separation of living, working, traffic and recreation which for many years has been used in town-and-country planning, has in my opinion resulted in disproportionate attention for forms of recreation far from home, whether there was relatively little attention for improvement of recreative possibilities in the direct neighborhood of the home. We have come to the conclusion that this is not right, because an important past of the time which we do not pass in sleeping or working, is used for activities at and around home. So it is obvious that recreation in the open air has to begin at the street-door of the house. The urban environment has to offer as many recreation activities as possible, and the design of these has to be such that more obligatory activities can also have a recreative aspect.

The very best standard of living is nothing if it is not possible to take a pleasant walk in the district, if the children cannot be allowed to play in the streets, because the risks of traffic are too great, if during shopping you can nowhere find a spot for enjoying for a moment the nice weather, in short, if you only feel yourself at home after the street-door of your house is closed after you.

According to the author, the importance of green-spaces in the urban environment ______.

A．is still unknown

B．is usually neglected

C．is being closely studied

D．has been full recognized

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第9题

Bionics is a recently developed branch of science, which has tremendous potential for impr

oving the life of mankind in our contemporary society. Bionics can be described as the study of systems in living creatures and the application of the knowledge gained from this study to the improvement of various kinds of man-made systems. The term bionics was coined around 1960, and much of what is known about the science of bionics has been discovered since about 1970.

Some researchers recently have studied the eyes of the common frogs and have discovered that a frog's eyes only find moving things such as insect-shaped objects and large, threatening objects. As a result of studying the eyes of frogs, scientists have constructed a simple electronic model of a frog's eyes which can track airplanes circling above an airport and then provide information to computer-run air traffic control systems. Someday such electronic eyes may provide the means to automatically guide automobiles by providing information about objects moving toward the automobile. Other scientists have studied the compound eyes of some insects and crabs and have built a seeing machine that is a simple model of the horseshoe crab eye.

The hearing of a number of creatures also has been studied extensively so that hearing machines can be developed. Bats have unusual hearing which can extend into the ultrasonic (超声的) range. The dolphin also has been studied extensively, and dolphins are able to navigate through water extremely effectively. Radar and sonar(声纳) systems which are used to help ships and planes navigate have been based on the sonar systems of both bats and dolphins.

Which of the following could be the best title？

A．Electronic Eyes

B．The Science of Bionics

C．Sonar Systems

D．The Hearing of Some Creatures

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第10题

Without proper planning, tourism can cause problems. For example, too many tourists can cr

owd public places' that are also enjoyed by the inhabitants of a country. If tourists create too much traffic, the inhabitants become annoyed and unhappy. They begin to dislike tourists and to treat them impolitely. They forget how much tourism can help the country's economy. It is important to think about the people of a destination and how tourism affects them. Tourism should help a country to keep the customs and beauty that attract tourists. Tourism should also advance the well-being of local inhabitants.

Too much tourism can be a problem. If tourism grows too quickly, people must leave other jobs to work in the tourism industry. This means that other parts of the country's economy can suffer.

On the other hand, if there is not enough tourism, people can lose jobs. Businesses can also lose money. It costs a great deal of money to build large hotels, airports, air terminals, first-class roads, and other support facilities needed by tourist attractions. For example, a major international-class tourism hotel can cost as much as 50000 dollars per room to build. If this room is not used most of the time, the owners of the hotel lose money.

Building a hotel is just a beginning. There must be many support facilities as well, including roads to get to the hotel, electricity, sewers to handle waste and water. All of these support facilities cost money. If they are not used because there are not enough tourists, jobs and money are lost.

Which of the following has most probably been discussed in the para. that goes before the para. ？ ______.

A．It is extremely important to develop tourism

B．Building roads and hotels are essential

C．Support facilities are highly necessary

D．Planning is of great importance to tourism

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