On a turbo-charged, medium-speed diesel engine, which of the following problems is an indication of a restricted air intake passage?（）
A . Engine is hard to start
B . Engine misses
C . Surges at governed RPM
D . Coolant temperature is too low
相似题目
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Which of the following conditions is realized by the turbo-charging of a previously naturally aspirated diesel engine?（）
A . Ignition lag increases
B . Lube oil system pressure increases
C . Brake specific fuel consumption increased
D . Mechanical efficiency increaded
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Which three objectives would be met by designing Layer 3 switching in the Campus Backbone of a medium size installation?（）
A . scale to a large size
B . increase router peering
C . provide a flexible topology with no spanning tree loops
D . control broadcasts in the backbone
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On a medium-speed main propulsion diesel engine, the crank-pin or crank journal bearings receive lubricating oil from （）.
A . a spindle lubricator
B . an oil jet
C . internal splashing
D . drilled passages in the crankshaft
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You are at a client site. It is a medium-sized business and needs a Cisco Catalyst switch that offers high availability and security. What type of Catalyst switches would you recommend？（）
A . Catalyst 2960 Series
B . Catalyst 3750 Series
C . Catalyst 4900 Series
D . Catalyst 6500 Serie
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Some medium and high-speed diesel engines require reduction gear units to provide a useful propeller speedIn most reduction gears, the bull gear（）
A . must churn the oil in the sump
B . is connected to the propeller shaft
C . is driven at the highest RPM
D . compensates for alignment variations between the engine and pinion gear
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Before shutting off the fuel supply to stop a medium or high–speed diesel engine, why is it necessary to allow the engine to idle for a few minutes?（）
A . To prevent internal damage form local overheating
B . To ensure the fuel nozzles are flushed clean
C . To clear the smoke stack
D . To let the waste heat boiler reduce its rate of steam generatio
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Which of the following conditions can cause above normal air temperature to develop in the intake manifold of a four-stroke/cycle turbo-charged diesel engine?（）
A . Clogged air intake falters
B . Piston blow-by
C . A defective after-cooler
D . Faulty exhaust valve
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Which characteristic is an advantage of Halon as a fire extinguishing medium?（）
A . Electrically non-conductive
B . Relatively inexpensive
C . Effective against chemicals containing an oxidizer
D . All of the above
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（） can be found on most medium to large merchant vessels even if the main engine is either a steam turbine or 2-stroke crosshead engine.
A . The medium speed 4-stroke trunk piston engine
B . The low speed 2-stroke crosshead engine
C . The medium speed 2-stroke crosshead engine
D . The low speed 4-stroke trunk piston engine
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One characteristic of a pulse type turbo-charging system is（）
A . high average exhaust manifold
B . greatly fluctuating inlet manifold pressure
C . constant exhaust manifold pressure
D . multiple exhaust pipes to the turbocharger
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Which is a disadvantage of Halon as a fire extinguishing medium?（）
A . Conducts electricity
B . Difficult to store
C . Large volume necessary to be effective
D . Ineffective in powdered metal fire
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If over a period of weeks the air-box pressure of a turbo-charged, diesel engine, operating at full load, appears to be dropping off, the cause can be （）.
A . open air-box drains
B . loss of cooling water to the diffuser
C . gradual fouling of the air filters
D . improperly timed exhaust valve
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Each cylinder liner on the marine medium speed engines （）.
A . is usually cooled by sea water
B . can be replaced when worn out
C . is in direct contact with the water in the bore of the cylinder
D . can t expand when heated
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You are anchoring in 16 fathoms of water．On a small to medium size vessel，the（）.
A . Anchor may be dropped from the hawse pipe
B . Anchor should be lowered to within 2 fathoms of the bottom before being dropped
C . Scope should always be at least ten times the depth of the water
D . Scope should always be less than 5 times the depth of the water
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The majority of medium speed and high speed marine diesel engines for main or auxiliary drive operate on the （） cycle.
A . two-stroke
B . four-stoke
C . long-stroke
D . short-stroke
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E-mail is a convenient, highly democratic informal medium for conveying messages that _______ well to human needs.
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We have developed into a medium¬_______ ¬¬enterprises with many branches and offices.
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Because of its intimacy, radio is usually more than just a medium; it is __________.
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In MLA style, the name of the book in a series is placed at the end of the entry, before the medium.
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The superiority of Internet as a mass medium lies in its high speed, diversification, personalized services, interactivity, openness, richness and globalization.
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Solvents are requried both as a reaction medium and for purification via ________.
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Because of its intimacy,radio is usually more than just a medium; it is_____.
A．firm
B．company
C．corporation
D．enterprise
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In a diesel engine, offers the heat energy directly; works as working medium and changes the heat energy to mechanical energy.
A.the burning of the fuel; medium shaft
B.fuel spray; fresh air
C.fuel; fuel spray
D.the burning of the fuel; the burned gas mixture
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E. coli is grown on a medium containing 15N for a long time. Cells were then transferred to medium containing only normal 14N. DNA samples were obtained for analysis after three rounds of replication
A．One with DNA containing both 15N and 14N
B．Two, one with DNA containing only 15N and one with DNA containing only 14N
C．Two, one with DNA containing both 15N and 14N and one with DNA containing only 14N
D．Three, one with DNA containing only 15N, one with DNA containing both 15N and 14N and one with DNA containing only 14N
