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When are windows the weak link in a building?
A．In the cold winter.
B．In the hot summer.
C．When air conditioners are turned on.
D．Both Ａ and Ｂ.
参考答案
更多 “ When are windows the weak link in a building?A．In the cold winter.B．In the hot summer.C．When air conditioners are turned on.D．Both Ａ and Ｂ. ” 相关考题
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What kind of drink did Joe order for himself when invited the princess?()
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The room is a little small; _______ it is so hot.
A.in additionB.in addition toC.additionalD.adding
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Smart WindowWindows not only let light in to cut down an electricity use for lighting, but the light coming through the window also provides heat. However, windows are not something people typically associate with being a cutting edge technology. Researchers are now working on new technologies that enable a window to quickly change from clear to dark and anywhere in between with a flip of a switch."It took us a long time to figure out what a window really is," says Claes Granqvist. He's a professor of solid-state physics at Uppsala University in Sweden. "It's contact with the outside world. You have to have visual contact with the surrounding world to feel well. " So, windows and natural light are important for improving the way people feel when they're stuck indoors.Yet, windows are the weak link in a building when it comes to energy and temperature control. In the winter, cold air leaks in. When it's hot and sunny, sunlight streams in. All of this sunlight carries lots of heat and energy. And all of this extra heat forces people to turn on their air conditioners. Producing blasts of cold air, which can feel so refreshing, actually suck up enormous amounts of electricity in buildings around the world.Windows have been a major focus of energy research for a long time. Over the years, scientists have come up with a variety of strategies for coating, glazing, and layering windows to make them more energy efficient. Smart windows go a step further. They use chromogenic technologies which involve changes of color.Electrochromic windows use electricity to change color. For example, a sheet of glass coated with thin layers of chemical compound such as tungsten oxide works a bit like a battery. Tungsten oxide is clear when an electric charge is applied and dark when the charge is removed, that is, when the amount of voltage is decreased, the window darkens until it's completely dark after all electricity is taken away. So applying a voltage determines whether the window looks clear or dark.One important feature that makes a smart window so smart is that it has a sort of "memory. " All it takes is a small jolt of voltage to turn the window from one state to the other. Then, it stays that way. Transitions take anywhere from 10 seconds to a few minutes, depending on the size of the window. The development of smart windows could mean that massive air conditioning systems may no longer need. "In the future," Granqvist says, "our buildings may look different. "Which of the following statements does not indicate the importance of windows as described in the first two paragraphs?A．Windows can change from clear to dark to save energy.B．Windows help to save energy by letting light in.C．Windows help to save energy by providing heat.D．Windows enable people to have contact with the outside world.
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What will be the benefit if the research on smart windows turns out to be successful, according to the last paragraph?A．The buildings will look different.B．Windows can be as large as you want.C．We may not need air conditioners any more.D．They are less expensive than traditional windows.
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____________ fire, sound the alarm and leave the building immediately.
A.In need ofB.In case ofC.In spite ofD.In charge of
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If a diesel engine turned over freely but failed to start, the cause could be ________.A.water in the fuelB.cold lube oilC.excessive starting air pressureD.excessive fuel pressure
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Steam smoke will occur when ______.A.extremely cold air from shore passes over warmer waterB.warm dry air from shore passes over cooler waterC.cold ocean water evaporates into warm airD.cool rain passes through a warm air mass
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Hygroscopic cargoes should be ventilated when ______.A.going from a warm to a cold climateB.the dew point of the outside air is greater than the dew point of the air in the holdC.the dew point of the air in the hold is very lowD.the outside dew point is 16°C and the cargo temperature is 12°C
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The fresh air intake of the inert gas system ______，A.Prevents the flue gas from falling below 3% content of oxygenB.Allows the inert gas piping to be used for gas freeing the tanksC.Opens when there is excessive vacuum on the deck water sealD.Enables outside air to mix with and cool hot flue gasses
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______ is a type of fog occurring close to the sea surface when the air is dry and cold-probably at least 9℃ below the sea surface temperature．A.MIXING FOGB.ADVECTION FOGC.RADIATION FOGD.ARCTIC SEA SMOKE
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A portable dry chemical fire extinguisher discharges by ______.A.gravity when the extinguisher is turned upside downB.pressure from a small CO2 cartridge on the extinguisherC.air pressure from the hand pump attached to the extinguisherD.pressure from the reaction when water is mixed with the chemical
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Smart Windows
1.Windows not only let light in to cut down an electricity use for lighting, but the light coming through the window also provides heat. However, windows are not something people typically associate with being a cutting edge technology. Researchers are now working on new technologies that enable a window to quickly change from clear to dark and anywhere in between easily.
2."It took us a long time to figure out what a window really is," says Claes Granqvist. He's a professor of solid-state physics at Uppsala University in Sweden. "It's contact with the outside world. You have to have visual contact with the surrounding world to feel well." So, windows and natural light are important for improving the way people feel when they're stuck indoors.
3.Yet, windows are the weak link in a building when it comes to energy and temperature control. In the winter, cold air leaks in. When it's hot and sunny, sunlight streams in. All of this sunlight carries lots of heat and energy. And all of this extra heat forces people to turn on their air conditioners. Producing cold air, which can feel so refreshing(使人清新的), actually suck up enormous amounts of electricity in buildings around the world.
4.Windows have been a major focus of energy research for a long time. Over the years, scientists have come up with a variety of strategies for coating, glazing(用玻璃覆盖), and layering windows to make them more energy efficient. Smart windows go a step further. They use some chromogenic(发色的)technologies involving changes of color.
5.Electrochromic(电致色的) windows use electricity to change color. For example, a sheet of glass coated with thin layers of tungsten oxide(氧化钨)works a bit like a battery. Tungsten oxide is clear when an electric charge is applied and dark when the charge is removed, that is, when the amount of voltage(电压)is decreased, the window darkens until it's completely dark after all electricity is taken away. So applying a voltage determines whether the window looks clear or dark.
6.One important feature that makes a smart window so smart is that it has a sort of "memory". All it takes is a small shock of voltage to turn the window from one state to the other. Then, it stays that way. Transitions take from 10 seconds to a few minutes, depending on the size of the window. The development of smart windows could mean that massive air conditioning systems may no longer need. "In the future," Granqvist says, "our buildings may look different."
文章(31~35)
Which of the following values of windows is NOT mentioned?A.They let light in to brighten the house.
B.They let light in to heat the house.
C.They let us have visual contact with the surrounding world.
D.They let us think about the outside world.
考题
The air-conditioners are tested for defects before leaving the factory.A:parts B:functions C:faults D:motions
考题
--The weather is too cold ______ Novemberthis year in Changsha.
--It was ______ when I came here years ago.A.for; colder
B.in; cold
C.in; hot
D.for; hotter
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单选题The hydraulic oil most likely to thin out when hot and thick when cold would have a viscosity index of（）A
20B
40C
60D
80
考题
单选题The fresh air intake of the inert gas system（）.A
prevents the flue gas from falling below 3% content of oxygenB
allows the inert gas piping to be used for gas freeing the tanksC
opens when there is excessive vacuum on the deck water sealD
enables outside air to mix with and cool hot flue gasses
考题
问答题Practice 1 Heat loss by sweating depends on the fact that when a liquid evaporates, it absorbs an enormous quantity of heat from its surroundings. Therefore, when I am of sweat evaporate, a great deal of heat is absorbed from the surface of the body in contact with it. 1______ 2______ The first is the amount of movement of air surrounding the body. The second is the amount of water vapor in the air that surrounds the body. 3______ For this reason, sweat evaporates very rapidly on windy days, and the rate of heat loss by sweating is much more than on a still day. This accounts for the fact that hot still days are much less comfortable than hot windy days. In contrast, the sweat evaporates very rapidly on hot windy days, and cools the body quickly and effectively. 4______ When air is carrying the maximum amount of water vapor that it can hold, it is said to be 100% saturated with water vapor. The relative humidity of the air is said to be 100%. Under these conditions the air cannot carry any water, so no water can evaporate. When the relative humidity is high, therefore, sweat cannot evaporate. Instead, it forms large drops and runs off your skin without cooling you. 5______ It is obvious that under these conditions, evaporation will be much more rapid. Therefore, sweating will be much more effective as a method of losing heat from the body. On a hot dry day, sweat evaporates as soon as it is formed, and you feel reasonably cool even though the temperature of your environment is very high.[A] When the air is very dry and carries no water at all, the relative humidity is said to be 0%.[B] The second factor is the amount of water vapor in the air－the humidity.[C] Hot windy days are much more comfortable than hot still days.[D] This heat transfer occurs even if the environment is hotter than the body.[E] When air moves over the surface of water, the amount of evaporation is greatly increased.[F] You might expect the highest incidence of a heat stroke when the maximum temperature is 100 and humidity is 50%.[G] Two factors affect the rate of evaporation of sweat, and therefore the effectiveness of sweating as a method of cooling the body.
考题
单选题（）is a type of fog occurring close to the sea surface when the air is dry and cold-probably at least 9℃ below the sea surface temperature.A
MIXING FOGB
ADVECTION FOGC
RADIATION FOGD
ARCTIC SEA SMOKE
考题
单选题In extreme weather conditions, either hot or cold, control of the air conditioning plant presents （） difficulties.A
fewB
littleC
a littleD
less
考题
单选题Hygroscopic cargoes should be ventilated when（）.A
going from a warm to a cold climateB
the dew point of the outside air is greater than the dew point of the air in the holdC
the dew point of the air in the hold is very lowD
the outside dew point is 16°C and the cargo temperature is 12°C
考题
单选题Hot air can hold（）.A
less moisture than cold airB
more moisture than cold airC
the same amount of moisture as cold airD
moisture independent of air temperature
考题
单选题Hygroscopic cargoes should be ventilated when（）.A
going from a warm to a cold climateB
the dew point of the outside air is greater than the dew point of the air in the holdC
the dew point of the air in the hold is very lowD
the outside dew point is 16℃ and the cargo temperature is 12℃
考题
单选题Steam smoke will occur when（）.A
Extremely cold air from shore passes over warmer waterB
Warm dry air from shore passes over cooler waterC
Cold ocean water evaporates into warm airD
Cool rain passes through a warm air mass
考题
单选题We’ve just installed two air conditioners in our apartment, _____ should make great differences in our life next summer.A
whichB
whatC
thatD
they
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