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The heat identified by only a change in temperature is known as （）.
A . sensible heat
B . latent heat
C . total heat
D . residual heat
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The lowest temperature at which fuel combustion becomes self-sustaining in the presence of a source of ignition, is defined as the （）
A . auto-ignition point
B . flash point
C . burning temperature
D . fire point
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In a flash evaporator, scale as a result of higher than normal temperatures in most likely to occur in the （）
A . second stage feed heater
B . saltwater feed heater
C . distillate cooler
D . second stage vapor separator
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For a flash type evaporator, the seawater heater will have to maintain a enough temperature to minimize scale formation（）
A . lower
B . higher
C . low
D . high
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As the temperature of an air mass decreases，the（）.
A . absolute humidity decreases
B . relative humidity increases
C . specific humidity decreases
D . dew point rise
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A bonding cable should be connected for cargo operations aboards a tank vessel as soon as the（）.
A . cargo has been loaded or discharged
B . cargo ghose is connected
C . cargo pumps are started
D . vessel is ready to handle cargo
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The tendency for lubricating oil to thin out at high temperatures and thicken at low temperatures will be characterized by a （）.
A . low viscosity index
B . high viscosity index
C . high neutralization number
D . low demulsibility quality
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The heat required to change a substance from a solid to a liquid while at its freezing temperature, is known as the latent heat of （）.
A . fusion
B . vaporization
C . condensation
D . sublimatio
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If the coolant temperature of a closed cooling water system for a diesel engine gradually increases, the trouble usually is （）
A . a broken shaft on the freshwater pump
B . an excessive accumulation of scale exchanger
C . an incorrect thermostatic element operating range
D . lube oil in the cooling water
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Reheating a hardening component to a temperature lower than the hardening temperature and then cooling it is known as （）
A . low temperature hardening
B . case hardening
C . annealing
D . tempering
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As the temperature for a given mass of air increase, the（）.
A . dew point increase
B . dew point decreases
C . relative humidity increases
D . relative humidity decrease
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If a refrigeration compressor is running continuously without lowering temperature as normal in the refrigerator, the trouble may be （）.
A . excessive condenser cooling water
B . warm food in the refrigerator
C . a shortage of refrigerant
D . s shortage of compressor oil
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All items such as steam pipes, exhaust pipes and fittings which, because of their location and operating temperature, present a hazard should be adequately lagged.That means the items should（）
A . not be put into operation too early
B . be pay adequate attention to
C . be used only when necessary
D . be coated with certain material
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As the temperature of the air reaches the dew point，（）.
A . rain must develop
B . fog may form
C . it begins to snow
D . water freeze
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The operating diesel generators will have their exhaust temperatures, cooling water and lubricating oil temperatures and pressures （） in much the same way as for the main engine.
A . to be kept
B . logged
C . changed
D . has remained
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The artwork Uncle Sam was created in 1917 as a recruiting poster for the US Army.
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听力原文：W: Sorry I did not come yesterday, because I had a temperature. Could you tell me the requirement for my term paper？
M: The theme of your paper can be about business management or touring resources in China, and the length of the paper should be no less than fifteen pages.
Q: What is the most probable relationship between the two speakers？
(19)
A．Manager and employee.
B．Salesman and customer.
C．Guide and tourist.
D．Professor and student.
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Is there something as truth？ For a good many centuries "the search for truth" has been （31
Is there something as truth？ For a good many centuries "the search for truth" has been (31) the noblest activity of the human mind, but the seekers after truth have come to such (32) conclusions that it often seems that very little progress has been made. (33) , there are many people who reel that we are actually going backward. They (34) , often contemptuously, that we have accumulated more "knowledge" than our ancestors, but they think we are farther from the truth than ever, or even that we have (35) the truth that we once possessed. If people look for anything long enough without finding it, the question naturally arises (36) the thing is really there to find. You have seen a picture of an animal with a lion's head, a goat's body, and a serpent's tail--and maybe an eagle's wings for good (37) There is plenty of evidence that each part of this animal (38) --but there is no (39) evidence that the parts ever occur in this combination. It is at least conceivable that the seekers after "truth" have made a similar mistake and invented an (40) combination.A.regardedB.consideredC.ponderedD.referred
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What is suggested as a reason for the shortage of business women？
A．Girls do not perform. so well as boys at school.
B．Most companies are reluctant to employ women.
C．Banks often refuse to give women large loans.
D．Women are very worried about the risk-taking in their careers.
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All items such as steam pipes, exhaust pipes and fittings which, because of their location and operating temperature, present a hazard should be adequately laggedThat means the items should .
A.not be put into operation too early
B.be pay adequate attention to
C.be used only when necessary
D.be coated with certain material
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The temperature of frozen Fargo is______for a full week.
A．six degrees below zero
B．twenty degrees or more below average
C．single digit or below zero
D．below zero
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听力原文：M: It's so cold now, but this morning it was so hot and sunny. I wish there was a way! could always be wearing the most suitable clothes for the temperature.
W: I recently read that in ten years we'll be wearing clothes that change with the weather. So when it's cold, our clothes will warm up, and when it's hot, our clothes will cool off.
M: Oh, very funny! So we'll be wearing huge clothes with built-in air conditioners and heaters.
W: I'm being serious! Researchers have discovered a method of treating fibers with plastic crystals capable of storing and releasing heat as the temperature fluctuates. These treated fibers absorb more heat than untreated fibers. Researchers are still working with this, but soon this process will be widespread.
M: That's fascinating. I didn't know that fibers had the capability of storing heat. How does that work？
W: These fibers work with the heat by rearranging their structures. The treated fibers move back and forth between two solid shapes.
M: I don't understand. What kind of shapes do they change into？
W: When the weather gets warmer, the crystals take on cube shapes and absorb heat. When the weather gets cooler, the crystals become cooler and come back to their original structure.
M: That's truly unbelievable. You said that it'd be a decade before this type of clothes will be available, What a shame! I don't think I can wait that long.
(23)
A．He is indifferent.
B．He is doubtful.
C．He is disgusted.
D．He is alarmed.
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Which of the following is the best reason for pouring a condensation impression material as soon as possible()
A．the degree of polymerization of condensation polymers is initially high and then decreases with time
B．evaporation of a volatile by-product causes shrinkage ofthe set material
C．If left unpoured，condensation impression materials expand as they absorb water from air
D．condensation polymers will start to react with the polymer of the impression tray and cause distortion
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Choose the best option for the sequence of A and B. Once the gas cloud has reached a certain temperature, it is hot enough for nuclear fusion to take place. A= nuclear fusion takes place B= the gas cloud reaches a certain temperature
A、A happens first
B、B happens first
C、A and B happen at approximately the same time
D、Not given
