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单选题
Marine four-stroke diesel engines are mainly （）.
A
of crosshead type
B
of trunk piston type
C
of low speed type
D
all the above
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causeD
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less even torqueB
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单选题For an ordinary modem marine four-stroke engine the inlet valves close （）.A
after TDCB
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most critical in a four-stroke cycle diesel engineB
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单选题（）, so they are widely used on board ship nowadays.A
Diesel engines have more advantages in comparison with gasoline enginesB
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sanitary waterD
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单选题（）uses one or two high pressure pumps for all the cylinders with one more standby, while（）have a separate high-pressure pump for each cylinder.A
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four cycleB
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crownC
piston rodD
connecting rod
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单选题Modern marine diesel engines using mechanical fuel injection, operate on a combustion cycle which is（）A
a combination of constant volume and constant pressureB
a combination of constant temperature and constant pressureC
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单选题A turbocharged, four-stroke/cycle diesel engine has a larger valve overlap than a naturally aspirated four-stroke/cycle diesel engine, in order to in crease the （）.A
temperature of the exhaust gasesB
energy supplied to the turbochargerC
air pressure to the intake manifoldD
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单选题Turbocharged four-stroke/cycle diesel engines utilize valve overlap for（）.A
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单选题Modern marine diesel engines equipped with mechanical fuel injection operate on a combustion phase within the cycle which is（）A
entirely constant pressureB
entirely constant temperatureC
a combination of constant volume and constant pressureD
a combination of constant temperature and constant pressure
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