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A1￡?When a ship in loaded condition floats at arbitrary water line, its displacement is ___to the relevant mass of water displaced by the ship.
A. equal
B. larger
C. smaller
D. equivalent
B2￡?The displacement of a ship is ___ to the total weight, all told, of the relevant loaded ship.
A. larger
B. equal
C. smaller
D. equivalent
B3. Which one is true?
A. Two main areas of skill are involved in the construction of ship.
B. There are distinct divisions in responsibilities between naval architects and marine engineers.
C. Each ship will assume varying proportions according to its type.
D. Ships can be divided into different categories from different perspectives. D4. Why a gearbox is needed in a ship driven by a medium-speed diesel engine?
A. To reduce the main engine speed.
B. To increase the main engine speed.
C. To govern the main engine speed.
D. To fix the propeller shaft.
B5. A propeller, in order to operate efficiently, must rotate at a relatively ___ speed.
A. high
B. low
C. fast
D. lowly
D6. Ina 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 B7. In a diesel engine, ________ works as working medium and changes the heat energy to mechanical energy, ___________ changes the reciprocating movement to rotary moment.
A. fuel spray; the burning of the fuel
B. the burned gas mixture; connecting rod
C. medium shaft; crankshaft
D. the burned gas mixture; piston rod
D8. One of the differences between a two-stroke engine and a four-stroke engine is, _________.
A. a two-stroke engine works without exhaust operation
B. a two-stroke engine works without compression stroke
C. a two-stroke engine works without expansion stroke
D. a two-stroke engine works without suction operation
D9. One of the differences between a two-stroke engine and a four-stroke engine is, _________.
A. a two-stroke engine can?ˉt work without cylinders
B. a two-stroke engine can?ˉt work without piston
C. a two-stroke engine can?ˉt work without crankshaft
D. a two-stroke engine can?ˉt work without a blower
C10. In a diesel engine, with the fuel is injected into the cylinder, ________________.
A. the piston is just coming upward from the bottom dead center.
B. the piston has moved about one-fifth of the up.
C. the piston has moved most of the way up and almost reached the TDC.
D. the piston has just past the TDC.
B11. ___________ is the main reason that reduces the power advantage of a two-stoke engine over a same size four-stroke one to about _________.
A. Inefficient scavenging; twice
B. Inefficient scavenging; 1.8 times
C. Fewer strokes in a circle; twice
D. Fewer strokes in a circle; 1.8 times
A12. If the engine is naturally aspirated, or is a small high-speed type with a centrifugal turbocharger, the period of valve overlap, i.e. when both valves are ____, will be _____, and the exhaust valve will close some 10?? ______ top dead canter.
A. open; short; after
B. closed; short; after
C. open; long; before D; closed; long; before
A13. In a two-stroke engine, there are always a series of openings known as ________, and in some circumstances, there are also openings known as _________, in the part of the cylinder liner inside the scavenging air box.
A. scavenging air ports; exhaust ports
B. inlet ports; scavenging air ports;
C. scavenging air ports; inlet ports
D. exhaust ports; inlet pots
A14. In some type of two-stroke engines, besides some small holes for ______, starting valve, safety valve, indicator cock, and so on, there is a large central opening in each cylinder cover for mounting the _________.
A. fuel valves; exhaust valve
B. exhaust valve; inlet valve
C. fuel valves; inlet valve
D. exhaust valve; fuel valve
C15. In a two-stroke engine, the piston consists of a lower part, which in named as ______ and usually made of _______, and a upper part, which is referred to as ______ and made of ______.
A. low-half, cast iron; top-half, heat-resistant steel
B. low-half, aluminum; top-half, stainless steel
C. piston skirt; cast iron; piston crown; heat-resistant steel
D. piston skirt; aluminum; piston crown; stainless steel
B16. In order to keep the oil film on the cylinder liner during the running-in period, the piston ring are slightly rounded __________________.
A. on both the external and internal top edges
B. on both the external top and bottom edges
C. on both the external and internal bottom edges
D. on all the four edges
D17. In order to control thermal stresses, some types of modern engines use piston with _________.
A. heavy wall and intensive cooling
B. heavy wall and no cooling
C. thin wall and no cooling
D. thin wall and intensive cooling
A18. In order to improve the working conditions of the crosshead bearing, the bearing pressure is made ______ and the peripheral speed is made ______ in later designs.
A. smaller, higher
B. higher, smaller
C. smaller, smaller
D. higher, higher
B19. When the heavy fuel oil is heated to achieve the viscosity of 10-15 cSt, ______ may occur. To avoid this, a _________ system is used in most occasions.
A. boiling and cavitations; low temperature
B. boiling and cavitations; pressurized
C. leaking and boiling; low temperature
D. leaking and boiling; pressurized D20. The fuel from the bunker tanks must be treated by ______ before entering the service tanks, from where the fuel enters _________.
A. centrifugal separators; the engine cylinder
B. oily water separators; the engine cylinder
C. oily water separators; the fuel supply system
D. centrifuges; the fuel supply system
A21. A full-flow 50|ìm filter is installed _________, so the injection system components on the main engine are safeguarded.
A. as close to the main engine as possible
B. as close to the main pump as possible
C. just before the fuel valve
D. just before the booster pump
B22. The booster pump, which supplies diesel oil to _________, should have a possibility of being powered by compressed air or by emergency power.
A. the main engines
B. the auxiliary engines
C. the emergency generator engine
D. the auxiliary engines and the main engine(s)
D23. ______is harmful for fuel pumps, fuel valves, cylinder liner, exhaust valve seats, and the turbocharger blades as well.
A. Bed combustion of the fuel
B. Bed atomization of the fuel
C. Liquid contaminants
D. Solid contaminants
B24. As an alternative to the conventional seawater cooling system, _________ is based on _______ principles about cooler locations, flow control and preheating, but with a central cooler and one additional set of pumps.
A. the central cooling system, different
B. the central cooling system, the same
C. the opening cooling system, different
D. the opening cooling system, the same
D25. An alarm device inserted between the deaerating tank and the expansion tank can notify the on-watching crew that _____________.
A. the expansion tank in lack of water
B. the expansion tank is over flowing
C. there is something wrong with cooling system
D. there is something wrong with the engine
D26. The ___________ cooling system needs least maintenance work for __________ in this kind of system.
A. open, the minimum components
B. open, the high cooling efficiency
C. central, there more coolers and a extra set of pumps
D. central, there is only one component contacts seawater
B27. About the jacket water, that of the auxiliary engines usually is circulated by_________ pumps,
And the main engine usually___________.
A.an engine-driven, as well
B.an engine-driven, has an independent pump
C.an independent, ad well
D.an independent, has an engine-driven pump
B28.In order to maintain a constant outlet water temperature of 80?a85 from the engine ,a
Three ¨Cway valve is installed___________.
A.at the jacket cooler outlet to control the flux through the engine
B.at the jacket cooler outlet to control the flux through the cooler
C.at the engine outlet to control the flux through the engine
D.at the engine inlet t to control the flux through the engine
C29.In modern installations ,the main engine and the standby auxiliary engines___________
A. can be started at low temperature and are free from preheating
B .usually are preheated by steam before being started
C. are kept at a constant temperature and free from preheating
D .are kept at a low temperature to save engine
C30.A marine diesel engine is started by_____________
A. supplying high pressure oil into a hydraulic motor
B .supplying high temperature air into the cylinder
C .supplying high pressure air into the cylinder
D .electrical igniting
C31.The staring air system of an engine on board usually has interlocks in to ____________
A .ensure a successful shutting down at emergency conditions
B .ensure a successful starting at emergency conditions
C .prevent the engine from starting at some abnormal condition s
D .prevent the engine from starting at emergency condition s
A32.In the starting system, the automatic valve is controlled by ________,and the cylinder start valves are controlled by_________.
A. pilot air; pilot air
B. handle; solenoid
C. handle, pilot air coming through the distributor
D. solenoid; pilot air coming through the distributor
B33.The starting air entering the cylinder begins when the piston _________.
A. has nearly come to TDC
B. has just past the TDC
C. has nearly come to BDC
D. has just past the BDC
C34. When starting an engine, the compressed air enters the cylinder when the corresponding piston is in position of its_________.
A. suction stroke
B. compression stroke
C. power stroke
D. exhaust stroke
A35. When an engine is starting and has got a sufficiently high speed, say about 20 rpm,_______.
A. the starting air supply is cut off and fuel is injected into the cylinders
B. the fuel feeding is cut off and the turning gear is put in
C. the starting air supply is cut off and the turning gear is taken out
D the electric blower is shut down and fuel is injected into the cylinders
B36. The air distributor is conventionally drive by and distributes into each cylinder by sequence.
A. camshafr; fresh air
B. camshafr; starting air
C. electronic motor which is controlled by a computer; fresh air
D. electronic motor which is controlled by a computer; starting air
D37. The following options are all the functions of lubricating oil except________.
A. removing heat and deposits
B. neutralizing acidic products
C. lubricating
D. improving combustion cfficiency
C38. ______diesel engines generally have two systems of lubrication:a total loss system feeding_____and a circulating system lubricating the running gear and cooling the pistons.
A. Large crosshead type , crossheads
B. High speed , the cylinders
C. Large crosshead type , cylinders
D. Four-stroke, pistons and cylinders C39. In soom diesel engine designs , the injection of cylinder oil is timed to impinge when the pistion|_____and only impinge on______.
A. is coming upward , cylinder ring belt
B. is going downward, piston ring belt
C. is coming upward, piston ring belt
D. is going downward,cylinder ring belt
C40. Large crosshead type engine generally has two lubrication systems, a function performed only by cylinder oil system is ______.
A. lubricating
B. cooling
C. sealing
D. cleaning
B41. Large crosshead type engine generally has two lubrication systems, a function performed only by crankcase oil system is_______.
A. lubricating
B. cooling
C. cleaning
D. neutralizing
B42. ?°The use of deposits in the piston crown which in turn results in a considerable reduction in heat transfer with subsequent overheating and thermal cracking.?±According to this sentence we can know that the principle reason of the overheating and thermal cracking is _______.
A. the use of a poor quality oil
B. the deterioration of its properties
C. the formation of deposits
D. the reduction in heat transfer ability C43. Gas exchange. Is a basic part of the cycle of an internal combustion engine. Is ______.
A. the supply of normal air and removal of compressed air
B. the supply of fuel oil and combustion of the atomized oil
C. the supply of fresh air and removal of exhaust gases
D. the supply of fresh air and removal of extra heat
D44. ?°This increase in charge air densety is accomplished on most modern diesel engine
types by use of exhaust gas turbo-charging,in which a turbine wheel driven by exhaust from the engine is rigidly coupled to a centrifugal type air compressor.?±According to this sentence,we can know that ______increases charge air density ,_____drives the compressor directly.
A. a modern diesel engine, a turbine wheel
B. a modern diesel engine . exhaust gases
C. a compressor , an exhaust fas turbocharger
D. a compressor ,a turbine wheel
A45. When the air charge contacts with the cylinders and pistons and mixes with the residual gases ,it will_____.
A. increase in temperature
B. lose its energy partly
C. expand and do work
D. begin to be compressed
C46. Usually we take the cooling effect of the air flown through the cylinder during the wverlap period as ________.
A. inevitable
B. harmful
C. helpful
D. unacceptable
C47. In slow speed two-stroke engines,the fresh air entering begins when______and stops as_____.
A. the inlet port is opened by the up coming piston;the port is closed by the down going piston
B. the inlet valve is opened by the down going piston ;the inlet valve is closed
C. the inlet port is opened by the down going piston ;the port is closed by the up coming piston
D. the inlet valve is opened
C48. The____is employed to warm up a large diesel engine before its starting. A. Hot air B. Hot boiler water C. Cylinder water D. hot seawater
D49. Which one of the followings may not be checked before engine sarting?
A. tank level
B. Various filters
C. drains
D. seawater temperature A50. When the direction handle of telegraph is moved,the relative position of camshat and crankshaft will be_____.
A. changed accordingly
B. unchanged
C. positioned ahead
D. positioned astern
A51. Which of the followings will affect the spray of fuel oil?
A. coke deposits
B. cylinder water temperature
C. asphalt in fuel oil
D. lub oil
B52. Which one of the following may contribute to the forming of coke around the nozzle of fuel valve ?
A, too much water in fuel oil B. too much asphalt in fuel oil
C. larger nozzle holes
D. more nozzle holes inlet valve
is closed
A53. The transmission system transmitting power forom the engine to the propeller is composed of shafts , bearings, and _____.
A. propeller
B. flying wheel
C. main engine
D. crankshaft
B54. The thrust from the propeller to the hull of the ship is transferred by ____.
A. tie rod
B. thrust block
C. bedplate of main engine
D. frame of main
engine
D55. ______is used to prevent the entry of sea water to the machinery space.
A. A special sealing gland
B. propeller
C. Tailshaft
D. Sterntube bearing
A56. Oil pressure in the lubrication system is _____than the static tea water head to ensure that sea water cannot enter the sterntube in the event of seal falure A. higher B. lower C. very higher D. very lower
B57. The propeller consists of a _____with several blades of helicoidal form attached to it.
A. shaft
B. boss
C. wheel
D. lever
B58. The difference between Fixed pitch propeller{FPP}and Controllable pitch propeller{CPP}is in that
A. for FP , once fitted,the position of the blades can also be3 changed in operation
B. for CP, once fitted ,the position of the blades can also be changed in operation
C. the CP type has a relatively smaller hub compared with the FP propellers
D. the FP type has a relatively larger hub compared with the cp propellers
A59. In conventional systems,the injection pressure_______,while it?ˉs_____in common rail diesel engine.
A. fluctuates with the engines speed to extent,independent of engine speed
B. keeps constant at all engine speed,dependent on the engine speed to some extent
C. keeps constant at all engine speed,independent of the engine speed
D. is decided by the engine speed,constant at all engine speed
A60. In common rail engines,the fuel is________before is injectsed into the cylinders.
A.stored in a common fuel line
B.pumped by the injection pump
B.at low pressure D.already atomized
C61. Ina common rail engine, the fuel is injected into cylinders________.
A. by injection pumps
B.at a time decided by the injection pump timing
C.by a signal opening the magnetic valves
D.at a time decided by the cam directly
A62. _________uses one or tow high pressure pumps for all the cylinders with one more Standby,while______have aseparate high-pressure pump for each cylinder.
A.A common rail engine, conventional engine
B.A conventional engine, common rail engines
C.A marine diesel engine, most other engines
D.A two-stroke engine, four-stroke engines
D63. A common rail engine has only one or tow high pressure pumps in operation at the same
time, and the injection into each cylinder_______.
A.can?ˉt be controlled very precisely
B.can?ˉt be controlled as flexibly as the separate pump system
C.can be controlled as flexibly as the separate pump system
D.can be controlled more precisely and flexibly
B64. The common rail engines show great advantages in combustion sepecially ______.
A. at high speed and full load
B. at low speed and part load
C. when heavy fuel oil is used at sea
D. when the ships run distance
A65. To meet the market requirements, a marine diesel engine should not be of________.
A. big size
B. fuel economy
C. low speed
D. high power
D66. The main purpose of changing main engine to electronic controlled is not to________.
A. control fuel injection time more precisely
B. control fuel injection rate more precisely
C. meet the environmental requirements
D. meet high engine speed requirements
A67. If a cam-controlled engine has a normal injection pressure at rate speed, the injection
pressure will be________ at slow speed.
A. a little lower
B. a little higher
C. too low
D. exactly the same
D68. If a camshaft-less engine has a normal injection pressure at rated speed, the injection
pressure will be _______at low speed.
A. too low
B. a little lower
C. a little higher
D. exactly the same
C69. _______is not a feature of the electronic controlled engines.
A. Lower fuel consumption
B. Better balanced cylinder power
C. A shorter overhaul period
D. Less smoke emission
A70. The mechanical exhaust valve operation system is replaced by _______ in an electronic
controlled ME engine.
A.a system with a Hydraulic Power Supply (HPS) unit
B.a system with roller guides for exhaust valves
C.a system with an electronically controlled Alpha Lubricator
D.a system with directly powered by electric motor
A71. ______ are mounted in pairs to protect the boiler against overpressure.
A. Safety valves
B. Water tubes
C. Steam stop valves
D. Blow down valves
B72. When steam is being raised on a boiler, the water level will normally __________.
A. drop as the boiler warms up
B. rise as the boiler warms up
C. remain unchanged until the boiler is hot enough
D. rise and fall with the steam demand
D73. The donkey boiler may be given a bottom blow ________.
A. to raise water level
B. only while making steam
C. to remove scum
D. when fire is secured
C74. Impurities from the boiler water surface can be removed though the _______.
A. safety valve
B. blow down valve
C. scum valve
D. feed check valve
C75. The exhaust boilers are used to recover some of ________carried in the exhaust gas from the
main engine.
A. water
B. oil
C. heat
D. steam
A76. The defective place in the furnace should be _________ with fire bricks.
A. paved
B. cleaned
C. welded
D. dismantled
C77. The safety valves are mounted in pairs to ___________the boiler against overpressure.
A. use
B. release
C. protect
D. effect
C78. The valve that prevents water from backing out of the boiler into the feedline is the _______.
A. bottom-blow valve
B. skin valve
C. feed-check valve
D. feed-stop valve
D79. The boiler feed water check valves are located on the ________.
A. feed pump suction line
B. hot well
C. shell of the feed heater
D. feed lines the boiler
B80. If in doudt as to the true water level when a boiler is being Oil-fired, you should _______.
A. take no measures
B. extinguish the fire as soon as possible
C. feed water to the boiler
D. open the blow down valve
A81. The boiler feed pump discharge pressure is higher than the steam dram pressure to _______.
A. ensure feed water flow into the boiler
B. keep the steam drum pressure high
C. prevent water hammer in the feed line
D. help the feed water flash to steam C82. Safety valves in a boiler vent to the ________.
A. Fuel tank
B. bilge
C. atmosphere
D. auxiliary exhaust line
D83. ________Will be used to blow away the combustion products from the tube surfaces.
A. The blow down valve
B. The scum valve
C. the ah?ˉrelase cock
D. The soot-blower
C84. Soot blowers should be used in proper sequence so that _______.
A. excess stresses will not be set up in the boiler
B. the decks will not be covered with soot
C. the soot will be swept toward the uptakes
D. there will not be a loss of steam pressure
C85. What is the first thing you would check on taking over a watch?
A. the bilges
B. the water
C. the periscope
D. the oil pressure
D86. One of the main purposes of refractories in a boiler furnace is to _________.
A. help preheat the air for the furnaces
B. help preheat the feedwater
C. protect economizer from excessive heat
D. prevent excessive furnace heat losses C87. the pump has a constant stroke and the amount of fuel delivered is regulated by
rotating _______ which has a specially arranged helical groove cut into it.
A. the pump cylinder
B. the pump cam
C. the pump plunger
D. the pump miler
D89. The pumps press oil into the cross-head bearing gap when the load on the shell is at its
lowest. What is the meaning of ?°its?± in the sentence above?′e°?D
B90. A vane pump belongs to _______according to its working principle.
A. reciprocating pump
B. positive displacement pump
C. centrifugal
D. centripetal pump
A91.Through a _______pump ,the liquid is transferred from the suction to the discharge by the mechanical variation of the volume of a chamber or chambers
A. positive displacement
B. ejector
C .centrifugal D. air compressor
C92.The gear and screw pumps are classified as_______.
A. variable stroke pumps
B. multistage pumps
C. positive displancement pumps
D. triple-ported pumps
B93.A gear pump belongs to ______according to its working principle.
A. reciprocating pumps
B. positive displancement pumps
C. centrifual pumps
D. centripetal pumps
B94.A Screw pump belong to______according to its working principle.
A. reciprocating pumps B .positive displancement pumps
C. centrifual pumps
D. centripetal pumps
A95.When the heat load begins to increase,the needle valve of an expansion valve will A. move in an opening direction B. move in a closing direction
C. either open or close D .not move at all
B96.When the refrigeration demand is small,_____________.
A .the expansion valve will move toward the wide open position
B. the expansion valve will move toward the closing position
C .the feeler bulb will conveys the high temperature
D. the superheat degree will raise.
D97.The thermostatic valve has a throttling action,that is to say the valve can_______.
A. stop the refrigent from flowing
B. force the refrigerant to flow
C. cause the refrigerant pressure to rise D .cause the refrigerant pressure to fall. A98.The thermal expansion valve responds to the_______.
A .amount of superheat in the vapor leaving the coil
B. amount of superheat in the liquid
C. temperature in the evaporator coil
D. pressure in the evaporator coil
B99.The bulb for the thermal expansion valve is located______.
A. in the middle of evaporator coils
B. near the evaporator coil outlet
C. near the evaporator coil inlet
D. on the bottlom row of evaporator coils
B100.If the compressorruns continually,the cause might be the_____.
A .high-pressure cutout switch is jammed open
B .low-pressure switch is jammed shut
C. thermal bulb is nt operating properly
D. scale trap is clogged
B101.The solenoid valve can be typed as a_______
A .thermal valve B. magnetic stop valve
C. bellows valve D .bimetallic valve
B102.In term of pressure and temperature tefrigerant in the compressor,what,happens to the primary?________.
A .its pressure and temperature are both lowered
B .its pressure and temperature are both raised
C. its pressure is lowered and its temperature is raised
D. its pressure is raised and its temperature is lowered
B103.What is the purpose of sub cooling R-12in the condenser?_______.
A. to increase the system efficiency by sensible heat transfer
B. to stop the liquid from flashing
C. to reduce the load on the compressor
D. to remove latent heat of vaporization and the suction piping transfer
A104.The purpose of the purge valve at the top of the condenser in a refrigerating system is to_____.
A .remove any air that may accumulate in the sustem
B. take out unpleasant fumes from the refrigerant
C. vent off excess refrigerant in an emergency
D. permit opening the refrigerating system for cleaning and inspecting
B105.The device used for low-pressure control and high-pressure cutout on a compressor is called a_______.
A. cutout
B. pressure controller
C .controller switch
D .cutout switch
A106.Where are the zinc plates located?__________.
A .saltwater side of the condenser B. refrigerant side of the condenser C .in the evaporater coil D. vacuun reducing valve
C107.Air or noncondensable gas is removed from a refrigeration system by a_________.
A. separating chamber
B.system of baffles
C .purge valve D. vacuum reducing valve
C108.The compressor suction line conveys the refrigerant vapor fronm_______.
A .condenser to evaporator B. compressor to condenser
C .evaporator to compressor D. receiver to compressor
C109.If the temperature in the icebox is too high,the trouble could be_______. A. a clogged scale trap B .are in the system
C. automatic controls not functioning properly
D. insufficient cooling water to the condenser
C110. If no gaskets are used in the piping joints of a Freon system,the joints must be_____.
A. finished joints B welded joints
C. ground joints
D. soldered joints
A111. When adding oil to a F reon system one must be sure that______.
A. all air is removed from the pump and fittings
B. there is not too high a suction pressure
C. the discharge pressure is not too high
D. the condenser is shutdown
C112.If the head pressure is too high,______.
A. the relief valve should open before the high-pressure cutout
B. the relief valve should open and let excess refrigerant go to receiver
C. the high-pressure cutout switch should operate before the relier valve opens
D. close in on the suction valve
A113.If the compressor-discharge pressure is higher the receiver temperature_______.
A. increase the amount of cooling water to the condenser
B. decrease the amount of cooling water to the condenser
C. add more refrigerant to the system
BD. removed some of the refrigerant from the system
114.The relief valve is located on the_______.
A. discharge side of condenser
B. discharge side of compressor
C. outlet of the evaporator
D. receiver tank
D115. The expansion valve on a Freon system controls the_______.
A. superheat of the gas leaving the compressor
B. back pressure in the evaporator
C. temperature of the icebox
D. superheat of the gas leaving the evaporator
A116.The scale trap is located between the_______.
A. king valve and the expansion valve
B. solenoid valve and expansion valve
C. evaporator and receiver D . compressor and evaporator
D117.If the high-pressure switch on the compressor opens and stops the compressor a possible cause could be:
A. too much cooling water going through the condenser
B. too enough refrigerant in the system
C. a leak in the evaporator coil
D. no enough cooling water going through the condenser
A118. Which of the following would not cause high suction pressure ?
A. insufficient refrigeration
B. leaky suction valves
C. expansion valve stuck open
D. suction valve not adjusted properly
D119.If a compressor runs continuously, the cause might be a ______.
A. defective thermal bulb
B. clogged scale trap
C. stuck high-pressure switch
D. stuck low-pressure switch
C120.The main distribution duct in an air conditioning system which contains the cooling coils and filters is called the______.
A. sublimation
B. desiccation
C. humidification
D. moisturization
AA121.The main distribution duct in an air conditioning system which contains the cooling coils and filters is called the_______.
A. manifold
B. condenser
C. chamber
D. plenum
D122. In a centrifugal Freon refrigeration system, the overall capacity of the system is increased by______.
A. opening more bypass lines
B. opening additional expansion valves
C. adding refrigerant
D. speeding up the machine
D123.The humidity of the atmosphere can be determined by the use of the______. A. anemometer B. potentiometer C. manometer D. psychrometer
A124.The device, which is installed in the compressor suction line to prevent liquid from entering
The compressor when hot gas defrosting,is called a______.
A. re-vaporator
B. receiver
C. dehydrator
D. solenoid
B125.A centrifugal compressor?ˉs purge recovery unit______.
A. reclaims water
B. purges air without losing refrigerant
C. purges air with some loss of refrigerant
D. purges lube oil from the refrigerant
D126.Which one of the following is not generally recognized as one constitute of bilge water? ______.
A. Oil leaking from tanks inside engine room
B. Engine rom cleanling water
C. Water leaking from the refrigerant
D. Sewage water
D127.When bilge water is heated in a holding tank, which one of the following statements is not accurate? ______.
A. The high temperature facilitates primary gravity separation
B. Most of the oil and organic solvents are raised to the top layer
C. The high the temperature is, the more the top oil will be collected
D. The high temperature has little use on the separation of emulsified oil
D128.When discharging bilge water, which criteria must be observed? ______.
A. The requirement for the oil content of bilge water discharged is 15 ppm
B. No discharge in sensitive waters
C. Any discharge in sensitive waters
D. International, national or local requirements have to be observed
D129.Which of the following methods might be used as the treatment on emulsified oil? ______.
A. gravity separation
B. centrifuge
C. Cyclone
D. Cross-flow membrane filtration
D130.What?ˉs the advantage of oily water separator that meets the requirement of MEPC 30(33) over
MEPC 107(49)?
a. more economic B. larger capacity on oil treatment
C. less costive
D. polishing device fouling prevention
C131.Which of the following methods might favor oil emulsion in bilge water?
A. Raising temperature
B. less use of surfactant
C. more use of solvent
D. polishing device fouling prevention
A132.Which of the following methods can not remove the non-separable emulsified oil in bilge water?
A. gravity separation
B. use of adsorbents
C. use of flocculents
D. use of chemical addition
C133.Disposal of all kinds of garbage but______ is prohibited within Special Areas.
A. plastics
B. comminuted or ground paper, rags, glass, metal etc.
C. food waste comminuted or ground
D. Incinerator ash
C134.When the garbage is mixed with some discharges having different disposal discharge requirements, ______shall apply.
A. any requirement appointed by the PSC officer
B. the most suitable requirement
C. the most stringent requirement
AD. no requirement
135.The basic process of biological sewage treatment consists of ______the liquor either by bubbling air through it or by agitating the surface.
A. oxygenating
B. oxidizing
C. oxidizing function
D. proportioning
A136.It is ______ that reduce the BOD by converting the organic content of the sewage to a chemically and organically inert sludge.
A. the bacteria
B. oxidizing
C. deoxygenating
D.proportioning
A137.Bacteria which live ______are said to be aerobic.
AA. in the presence of oxygen B. without oxygen
C. in the presence of nutrition
D. without nutrition
138.When anaerobic bacteria convert the sewage to an inert sludge, ______.
A. no oxygen is needed
B. oxygen
C. oxygen is given off
D. no gas is produced
A139.Both fuel oils and lubricating oils require ______ before passing to the engine.
A. treatment
B. heating
C. cooling
D. boiling
A140.The treatment of the fuel oils involves storage, heating, filtering and______.
A. centrifuging
B. pressurizing
C. atomization
D. igniting
D141. ______is used to separate two liquids or a liquid and solid and solids as in contaminated oil.
A. Oily-water separator
B. Purifier
C. Clarifier
D. Centrifuge
A142.Where a centrifuge is arranged to separate two liquids, it is known as a ______.
A. purifier
B. clarifier
C. liquid-separator
D. oily-water separator
B143.Where a centrifuge is arranged to separate impurities and small amounts of water from oil it is known as a ______.
A. purifier
B. clarifier
C. liquid-separator
D. oily-water separator
C144. ?°A centrifuge consists of an electric motor driving a vertical shaft on the top of which is mounted the bowl assembly.?± According to this sentence, we can know that ______ is mounted on the top of the vertical shaft.
A. a centrifuge
B. an electric motor
C. a bowl assembly
D. a driving motor B145.A centrifuge of which the bowl is arranged as the upper and lower parts separate discharge the sludge______.
A. by opening the separator manually
B. by separating the lower part from the upper part automatically
C. by separating the upper part from the lower part automatically
D. continuously
A146.Before the sludge in a purifier is ejected, ______.
A. the oil feeding is stopped and replaced by admitting flushing water.
B. the flushing water feeding is stopped and repalaced by admitting oil.
C. the feeding of dirty oil and flushing water is stopped.
D. the feeding of dirty oil and flushing water is admitted
A147.A flash-type evaporator discharges heated seawater into a chamber that is maintained at a pressure______ than the vapor pressure of the entering heated seawater , and subsequently the flashed water vapor pressure of the entering heated seawater, and subsequently the flash water vapor thereby produced.
A. lower condensing
B. higher cooling
C. lower cooling
D. higher condensing B148.The design of ______ for a flash type evaporator is of critical importance because it must provide an optimum feedwater spray pattern that facilitates the flashing process, and it must also maintain a pressure differential between successive stage.
A. condenser
B. flashing device
C. lashing device
D. vacuum pump
D149. Which one of the followings might not be employed to create vacuum for flash type evaporator______.
A. high-pressure steam-driven air-ejector
B. motor-driver vacuum pump
C. water-motivated air eductor
D. centrifuge pump
B150.The flash-evaporator is different with the submerged-tube evaporator in that for the
Former______..
A. Water is heated into vapor on heating surfaces
B. Water is vaporized by pressure difference
C. There are no heating-transfer surfaces
D. There are more heating-transfer surfaces
C151.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
B152. For a flash type evaporator , a demister is located______. the condenser. A. After B. before C. inside D. outside
D153. Among the basic categories of equipment , which of the following is used to convert
Hydraulic energy into continuous rotary motion?
A. Hydraulic pumps
B. Valves
C. Hydraulic cylinders
D. Hydraulic motors
D154. ______ are used to limit the pressure in any particular portion and mainly contron the pressure after the valve.
A. Relief valves
B. Check valves
C. Safety valves
D. Reducing valve A155 The rotor of the hydraulic motor rotates at a speed proportional to the ______.
A. flow of oil
B. pressure
C. A and B
D. temperature of oil
B156. What type of valve is used to direct the flow hydraulic fluid?
A. Relief valve
B. Direction control valve
C. Stop valve
D. Pressure control valve
B157______play a very important part in hydraulic systems by preventing interaction between different parts of the hydraulic circuit.
A. Motors
B. Check valves
C. Safety valves
D. Reducing valve
A158. Which of the following can be used in hydraulic transmission system? ______.
A. Hydraulic oil
B. Animal oil
C. Light oil
D. Fuel oil
C159. Among the basic categories of equipment, which of the following are used to convert are hydraulic energy into linear motion? ______.
A. Hydraulic pumps
B. Valves
C. Hydraulic cylinders
D. Hydraulic motors
D160. The crane is usually mounted on a pedestal to offer adequate ______ to the operator.
A. time
B. space
C. length
D. visibility
B161. When the union purchase derrick is operated, one derrick is positioned over the quayside and the other almost vertically over the ______..
A. dock
B. hold
C. pedestal
D. machinery space
C162 .Cargo handling unit is rated according to the ______to be lifted.
A. cargo crane
B. Jib
C. safe working lead
D. oil pressure
A163. ______ are used for cargo handling.
A. Cranes
B. Mooring winches
C. Windlasses
D. Foreman
C164. ______are used to handle anchors and chains.
A. Cargo winches
B. Mooring winches
C. Windlasses
D. Cargo hatches
B165. ______ are used for hauling in or letting out the wires which fasten the ship to the shore.
A. Cargo winches
B. Mooring winches
C. Windlasses
D. Cargo hatches
B166. When the power is shut off ,the wire ______.
A. becomes slack
B. can not be paid out unless the brake is overhauled or wire unless manually operated
C. will be let out because the brake is out of work
D. may be pay out duo to no power
D167. In an automatic mooring winches, the wire is paid off the barrel at a ______ tension and is
recovered at ______tension.
A.lower/higher
B.maximum/higher
C.predetermined maximum/higher
D.predetermined maximum/lower
A168. The spur geared mooring winches have advantages over worm geared ones in ______.
A. higher efficiency of the gear train while reversing
B. the higher gear ratio
C. the multi-start feather
D. higher recovering speed
D169. The advantage of the control equipment is ______.
A. that the transmitter is on the bridge
B. the local manual control can be achieved
C. that remote control cab be achieved
D. simple in construction and reliable in operation
B170. The function of the cut-off lever is ______.
A. to provide electrical signal
B. to provide feed-back
C. to provide local manual control
D. to provide right rudder angle
A171. Another name for the ?°swash plate?± in the variable delivery pump is ______.
A. tiltable disc
B. gravity disc
C. distributing disc
D. catch plate C 172. Which of following is NOT true according to the passage?
A. Both the main steering gear and the auxiliary steering gear should be operated
B. The alarms fitted to the remote control system should be operated
C. The emergency generator compartment should be checked
D. The communication system between the bridge and the steering gear compartment should be operated
A173. According to the passage, during the tests, ______.
A. the rudder should be moved through its full extent
B. the rudder should be moved in starboard direction
C. the rudder should be moved with the ship at maximum speed
D. the rudder should be moved with the ship at minimum speed
C174. The actual rudder angle reading is ______.
A. rudder angle indicator reading
B. the desired rudder angle reading
C. the measured rudder angle reading
D. the intended rudder angle reading
D175. What would the amps be at 240 volts with an 8 ohm resistance ? ______.
A. 32.5 amps
B. 25 amps
C. 1.5 amps
D. 30 amps
D176. If two A.C.generators are operated in parallel, the load is distributed evenly by ______.
A. a rheostat
B. a balancing coil
C. changing field excitation
D. adjusting the governor settings
A177. The voltage output of an A.C. generator is controlled by ______.
A. varying the D.C.exciter voltage
B. varying the reluctance of the air gap
C. regulating the speed of the prime mover
D. shorting out part of the armature windings
C178. Generator brushes are staggered to ____________.
A. reduce current pulsations
B. reduce brush chatter
C. prevent uneven commutator wear
D. allow greater power generation
A179.Which is an acceptable means of correcting high mica between commutator bars ? ______ ______.
A. undercutting
B. sanding
C. burnishing
D. filing
B180. When current and voltage reach maximum values at the same time , the power factor is ____________.
A. minimum
B. maximum
C. leading
D. lagging
B181. If a voltmeter is connected across a line , it must be protected with a ___________.
A. shunt
B. high-resistance coil in the armature circuit
C. low- resistance coil in the armature circuit
D. shunt and a coil of high resistance
C182. If two A.C. generators are to be operated in parallel , the lode is distributed evenly by ____________.
A. means of rheostat C. adjusting the governor settings
B. a balance coil D. changing excitation
B183. A circuit that has one wire in contact with the hull of the ship is a ____________.
A. series circuit
B. short circuit
C. grounded circuit
D. closed circuit
C184. The emergency generator or emergency battery is connected to ______ on most large ship.
A. distribution boards
B. section boards
C. emergency switch boards
D. closed circuit
C185. Switchboard may be of the dead-from type in which all live part are installed behind ______ and only the operation handles and instruments are on the front. A. the capstan B. the collector C. the panels D. the surface
D186. Shore power must be _____________ during dock repair.
A. disconnected
B. switched off
C. cut off
D. connected
A187. The current flowing first in one direction and then in another is called ______ current.
A. an alternating
B. a rush
C. a direct
D. an exciting
D188. The switchboards for a.c. systems differ form the d.c. switch gear in that open type panels are generally ____________ and the dead-front switch gear is the common role.
A. permissibly
B. permissible
C. no permissible
D. not permissible
A189. The liquid flowing in the capillary is such that the difference in ______ readings taken before the capillary and after it is related to the oil viscosity.
A. pressure
B. velocity
C. flow rate
D. temperature
B190. ____________ shall be continuously powered and shall have an automatic changeover to a stand by power supply in case of loss normal power supply.
A. cooling system
B. alarm system
C. the air conditioning installation
D. the mooring equipment
B191. ____________ is a machine by which electrical energy is transformed in to mechanical energy.
A. an alternator
B. an electric motor
C. a diesel engine
D. a main switchboard
A192. Current changing in direction and rising and falling value is ____________.
A. A.C.
B. D.
C. C. generator
D. fresh water generator C193. The separate supplies are connected in either star or delta formation . The
star formation is most commonly used and requires ______ slip-rings on the alternator.
A. two B .three C. four D. five
D194. D.C. generators are classified according to the manner in which ______ .
A. they are used
B. the field winds are connected to the road
C. the armature circuit is connected to the road
D. the field windings are connected to the armature circuit
A195. The purpose of the commutator and brushes on a D.C. generator is to __________.
A. change A.C. to D.C. current
B. change D.
C. to A.C. current
C. neutralize armature reaction
D. carry current to the outside circuit D196. The lode between two steam-driven alternation operating in parallel may ba adjusted by varying ___________.
A. the speed of the alternators
B. the field strength of the machines
C. the power factor of the alternators
D. steam supply to the prime movers
C197,When would you ground an electric hand tool ?____________.
A. When it is a D.C. machine
B. When it is a A.
C. machine
C. Any machine that operates on over 100 volts
D. Only when working on wet steel plates
B198. All of the following operating characteristics are listed on the name-plates of motors used aboard ship except the _________.
A. temperature C. horsepower
B. input kilowatts D. operating voltage
C199. A probable cause for a turbo generator tripping out on overspeed is a sudden __________-.
A. loss of field excitation C. total loss of load
B. large increase in load D. loss of steam pressure
C200. The correct phase rotation of a three-phase alternator can be checked with a ___________.
A. dynamometer C. three-phase motor
B. power factor meter D. polyphase voltmeter
A201. A voltmeter is connected in a circuit in___________.
A .parallel C. series
B. series parallel D. relay
D202. When two D.C. generators operate in parallel , they are protected against motorizing by ________.
A. blow out coils C. under voltage trips
B. governor relay D. reverse current trips
D203. The frequency of the alternating current generated by a synchronous generator is governed by the speed and the _________.
A. full excitation C. power factor
B. load D. number of poles
A204. The load rating of an A.C. generator is determined by the ___________.
A. internal heat it can withstand C. load it is capable of supplying
B. load it can carry continuously D. overload it can carry for a specified time only
C205. Which of the followings is NOT the advantages of the remote control and automation of engine operations? ____________.
A. Routine supervisory labor particularly the unproductive night-service labor is reduced
B. Engine mal-operation is automatically sensed and Manned.
C. The engine mom need be manned at night in bad weather or close waters
D. Some remedial measures can be taken automatically.
B206. In the event of failure of an auxiliary such as a lubricating pump, the standby pump is started and put on the line automatically. ?°the line?± in this sentence refers to ____________
A. fuel manifold
B. lubricating pipe line
C. auxiliary engine pipe line
D. generator output line
D207. TWO STEP CONTROLER ACTION is mainly____________.
A. proportional control
B. integral control
C. derivative control
D. on-off control
D208. The word ?°offset?± most probably means__________.
A. predetermined value
B. measured value
C. off-limit
D. sustained deviation
D209. Which kind of the following controllers is the most sophisticated controller?_________.
A. Proportional controller
B. Integral controller
C. Derivative controller
D. PID controller
A210. From the passage, we can learn that the simplest controller action is _________.
A. two-step controller action
B. proportional controller action
C. integral controller action
D. derivative controller action
D211. _________control system is one in which the control action is independent of the output .
A. Feed back
B. Negative feed back
C. Close loop
D. Open loop
D212. Domestic water pump is started automatically by __________ which operates as the water level falls to a predetermined level.
A. a level controller
B. a temperature switch
C. a floating ball
D. a pressure switch
C213. After the trouble of the automatic control system has been completely eliminated, assistance is _________ required.
A. remained
B. still
C. no longer
D. much more
D214. The alternating current generator supplying a load has a voltage drop resulted from the load .When the load has a lagging power factor this voltage drop__________.
A. is small
B. may be neglected
中华人民共和国海事局 2006年第3期海船船员适任证书全国统考试题(总第41期) 科目：轮机英语试卷代号：805 适用对象：无限、近洋航区3000KW及以上船舶二/三管轮 （本试卷卷面总分100分，及格分为70分，考试时间为100分钟） 答题说明：请选择一个最合适的答案，并将该答案按答题卡要求，在其相应位置上用2B铅笔涂黑。第1题至74题，每题1分，第75题至78题，每题1.5分,第79题至80题, 每题10分。 一、单项选择题 1. A diesel engine is similar to a gasoline engine except that the former has no ______. A. cross-head B. spark plug C. connecting rod D. cylinder 2. A diesel engine which is rated for normal operation at a crankshaft speed of 800 RPM, is commonly classed as a ______. A. slow-speed diesel B. medium-speed diesel C. high-speed diesel D. constant-speed diesel 3.Which of the diesel engine components listed increases air density and helps to improve engine operating efficiency? A. Impeller B. Compressor C. After-cooler D. Exhaust diffuser 4.For a given size engine, the two-stroke/cycle diesel engine will deliver more power than a four- stroke/cycle diesel engine because ______. A. it has a longer power stroke B. more air gets into the cylinder each stroke C. it develops twice as many power strokes at the same speed D. higher combustion pressure is developed 5.The intake valves in a diesel engine are reseated by ______. A. cam followers B. push rods C. combustion gases D. valve springs 6.According to the way the energy of the exhaust gases is utilized, pressure-charging can be divided into two main systems, namely, the constant-pressure system and ______. A. the pulse-phase system B. the pulse Doppler system C. the pulse system D. the pulse interval system 7.An over-speed safety device is usually fitted to a generator engine for______in the event of over- speed. A. cutting power off the engine B. increasing the fuel pump setting C. braking the crankshaft D. stabilizing the ship speed 8.What preventative maintenance should be done frequently to diesel engine starting air receivers? A. Drain the accumulated moisture. B. Test the relief valves. C. Watch the temperature to prevent fluctuations in pressure. D. Clean the interior to remove oil and foreign matter. 9.Immediately after any diesel engine is started, the engineer should check the ______. A. crankcase pressure B. lube oil pressure C. seawater pressure D. exhaust temperature 10. A controllable pitch propeller on a diesel driven vessel eliminates the need for ______. A. friction clutches B. disconnect clutches C. reversing gears D. reduction gears 11.In motor ship, ______is often used to recover some of the heat carried in the exhaust gases from the main engine. A. an diesel oil heater B. a waste heat boiler C. a fresh water generator D. a donkey boiler 12.An exhaust gas bypass is installed on a waste heat boiler in order to ______. A. bypass exhaust gas at high loads to prevent excessive back pressure B. bypass a portion of the exhaust gas at peak loads for better efficiency C. recycle exhaust gas to the turbocharger D. minimize moisture condensation in the boiler gas passages at low loads 13.Prior to lighting off a cold automatically fired auxiliary boiler, you should ______. A. check and regulate the water level B. close the air cock once fires are lit C. blow down the gage glass D. assure protective steam flow 14.Flame failure in an automatically fired auxiliary boiler can mostly result from a/an ______. A. incorrect electrode setting B. incorrect nozzle position C. clogged fuel nozzle D. broken high tension lead 15.Waterside scale in a fire-tube boiler may cause ______. A. increased heat transfer B. fireside erosion C. high steam demand D. overheated tubes 16.Which of the following will be the advantage of a centrifugal pump as compared with a reciprocating pump? I. Its discharge is continuous; II. It has no internal valves; III. Upon accidental closing of discharge valve, excessive pressure will not build up A. I, II B. II, III C. I, II, III D. II only 17.Why are removable sleeves installed on centrifugal pump shafts? A. They make it easier to replace the pump shaft packing. B. They can be economically replaced as they wear out. C. They can be removed when it is necessary to lighten the weight of the pump. D. They increase the strength of the shaft. 18.If one of the bilge system manifold valves does not properly seat, the ______. A. bilge well connected to that valve, plus the second bilge well being pumped will be completely emptied B. bilge system will lose vacuum and prevent the other bilges from being pumped out C. bilge well aft connected to that valve will siphon(虹吸) its contents to the forward bilge wells D. discharge pressure will be too high. 19.Which of the listed statements is correct concerning the starting of centrifugal pumps? A. They should always be started with the discharge valve closed. B. They should always be started with the discharge valve opened. C. A priming pump is always required to flood the impeller suction. D. They should always be started with the sealing line valves closed. 20.The simplest method to use for determining if a centrifugal pump is operating as designed, is to ______. A. closely observe the pump discharge temperature B. close off the discharge valve, and watch for a rise in pressure C. momentarily close off the suction valve, and watch for a rise in pressure D. use a clamp on ammeter and compare the readings to past records
轮机英语名词性专业术语的特点及翻译摘要：研究轮机英语名词性专业术语的特点，重点探讨轮机英语名词性专业术语 构词特点、词法特点和语义特点，并讨论轮机英语名词性专业术语的翻译方法和 翻译技巧． 关键词：轮机英语；名词性专业术语；特点；翻译技巧 The characteristics of nominal terms of marine engineering English and their translation Abstract The characteristics of special nominal terms of marine engineering English are explored with a focus on three aspects----word formation，morphology and semantics．The translation techniques employed in translating special nominal terms of marine engineering English are also discussed． Key words marine engineering English；special nominal terms；characteristics； translation techniques 0 引言 轮机英语中有大量的名词性专业术语，这些术语在构词法、词法和语义等方面都有它自身的特点，这些特点又决定了其在汉译时必须选取特定的翻译方法和翻译技巧，因此，掌握轮机英语名词性专业术语的特点以及了解相应的翻译方法和技巧对于学习和翻译轮机英语是非常重要的．确实有一批工程技术人员，他们了解船舶机械的构造和原理，英语功底也比较好，而且对翻译表现出浓厚的兴趣，但是在翻译轮机英语时常常会感到茫然，原因之一可能就是由于对轮机英语中名词性专业术语的特点不够熟悉，对相应的翻译方法和翻译技巧缺乏分析和掌握．本文尝试归纳出轮机英语名词性专业术语的几个特点，并有针对性地提出翻译方法和技巧，以期对提高轮机英语的翻译质量有所帮助． 1 轮机英语名词性专业术语的特点 轮机英语属于科技英语，其词汇具有科技英语词汇的特点，如大量使用专用词汇，常用词汇具有专业意义，词性的转换较多等等．此外，轮机英语名词性专
第一章汽车总论 1)Today’s average car contains more than 15,000 separate, individual parts that must work together. These parts can be grouped into four major categories: body, engine, chassis and electrical equipment 。P1 现在的车辆一般都由15000多个分散、独立且相互配合的零部件组成。这些零部件主要分为四类：车身、发动机、底盘和电气设备。 2)The engine acts as the power unit. The internal combustion engine is most common: this obtains its power by burning a liquid fuel inside the engine cylinder. There are two types of engine: gasoline (also called a spark-ignition engine) and diesel (also called a compression-ignition engine). Both engines are called heat engines; the burning fuel generates heat which causes the gas inside the cylinder to increase its pressure and supply power to rotate a shaft connected to the power train. P3 发动机作为动力设备，常见的类型是内燃机，其原理是通过发动机缸内的液体燃料燃烧而产生能量。发动机可分为两类：汽油机（点燃式）和柴油机（压燃式），都属于热力发动机。燃料燃烧产生热量使缸内气压上升，产生的能量驱动轴旋转，并传递给动力传动系。 第二章内燃机 1)Power train system: conveys the drive to the wheels 2)Steering system: controls the direction of movement 3)Suspension system: absorbs the road shocks 4)Braking system: slows down the vehicle P4 传动系把发动机输出的扭矩传递给驱动轮。传动系包括离合器（对应机械变速器）或液力变矩器（对应液力自动变速器）、变速器、驱动轴、主减速器、差速器和驱动桥。 5)Drum brakes have a drum attached to the wheel hub, and braking occurs by means of brake shoes expanding against the inside of the drum. With disc brakes, a disc attached to the wheel hub is clenched between two brake pads. P6 鼓式制动器的制动鼓和轮毂连接，制动蹄张开压紧制动鼓内侧从而产生制动。在盘式制动器上，连着轮毂的制动盘被紧紧夹在两个制动块之间。 1)Linking the piston by a connecting rod to a crankshaft causes the gas to rotate the shaft through half a turn.The power stroke"uses up"the gas,so means must be provided to expel the burnt gas and recharge the cylinder with a fresh petrol-air mixture:this control of gas movement is the duty of the valves;An inlet valve allows the mixture to enter at the right time and an exhaust valve lets out the burnt gas after the gas has done its job . P10 活塞通过连杆和曲轴连接，使得气体带动曲轴旋转半圈。作功冲程耗尽了所有的气体，这样就必须采取相应的措施排出废气并且向气缸内充入新的可燃混合气：气体的运动由气门来控制。进气门使可燃混合气在恰当的时刻进入气缸，排气门使燃烧后的废气排出气缸。 2)The spark-ignition engine is an internal-combustion engine with externally supplied in ignition,which converts the energy cntained in the fuel to kinetic energy.The cycle of operations is spread over four piston strokes. To complete the full cycle it takes two revolutions of the crankshaft. P11 火花点火式发动机是由外部提供点火的内燃机，从而将含在燃料内的能量转化成动能。发动机的一个工作循环分布在活塞的四个行程中，一个完整的工作循环曲轴需要转动两圈。 3)The oil pump in the lubricating system draws oil from the oil pan and sends it to all working parts in the engine. The oil drains off and runs down into the pan. Thus,there is constant circulation of oil between the pan and the working parts of the engine. P15
2015综合A真题及答案 第一部分词汇选项 1. I will not tolerate that sort of behavior in my class a. control b. observe c. regulate d. accept 2 .she showed a natural aptitude for the work. a. sense b. talent c. flavor d. taste 3. most people find rejection hard to accept. a. Excuse b. client c. refusal d. destiny 4. The organization was bold enough to face the press. a. Pleased b. powerful c. brave d. sensible 5. They were locked in mortal combat. a. Deadly b. open c. actual d. active 6. We were attracted by the lure of quick money. a. Amount b. supply c. tempt d. sum 7. The procedures were perceived as complex and less transparent. a. Clear b. necessary c. special d. correct 8. The stock exchange is in turmoil following a huge wave of selling. a. Service b. danger c. disorder d. threat 9 .He believed that Europe must change or it will perish. A. Survive b. last c. die d. move 10. There was a simultaneous trial taking place in the next building. a. Fair b. full c. coexisting d. public 11. They promote assimilation of ethnic groups into the main-stream culture. a. Policy b. value c. equality d. integration 12. A salesman’s cardinal rule is to satisfy customers. a. Principal b. official c. simple d. legal 13. I must compliment you on your handling of a very difficult situation. a. Silence b. praise c. assure d. complain 14. We lived for years in a perpetual state of fear. a. Emotional b. nervous c. terrible d. continuous 15. The starving children were a pathetic sight. a. Common b. unexpected c. unforgettable d. pitiful
中华人民共和国海事局 2009年第5期海船船员适任证书全国统考试题(总第48期) 科目：轮机英语试卷代号：803 适用对象：无限、近洋航区3000KW及以上船舶大管轮 （本试卷卷面总分100分，及格分为70分，考试时间为100分钟） 答题说明：请选择一个最合适的答案，并将该答案按答题卡要求，在其相应位置上用2B铅笔涂黑。第1题至82题，每题1分，第83题至94题，每题1.5分。 一、单项选择题： 1. The reason why more and more of the large merchant vessels are being powered by medium-speed diesel engines is . A. they operate between 150 and 450 rpm B. they are connected to the propeller by gearing C. their smaller size and weight D. they can be connected directly to the propeller without gearing 2. The closing of the exhaust valves used on a modern, large, low-speed, main propulsion diesel engine may be directly provided by . A. large conical springs B. compressed air pressure C. hydraulic pressure D. exhaust gas pressure 3. One of the factors limiting the amount of toad which can be put on a modem marine diesel engine is the . A. governor sensitivity B. exhaust temperature C. fuel injection pressure D. speed of the cam shaft 4. The desirable properties or a marine fuel oil should inc lude . A. high flash point and high viscosity B. low flash point and high viscosity C. low heating value and high sulphur content D. high heating value and low sulphur content 5. As the plunger moves upwards in the barrel, injection will commence once the plunger bas the spill ports and the pressure builds up. A. opened up B. closed off C. lined up D. taken off 6. In an auxiliary diesel engine bypass type lubricating oil system, the main lube oil pump forces . A. all of the oil used by the engine through a filter B. some of the oil used by the engine through a filter C. some of the oil used by the engine through a centrifuge D. all of the oil used by the engine through a centrifuge 7. Because the circulating water is in a closed loop, is installed to cater for expansion and contraction of the water at different conditions of operation. A. an expansion joint B. a drain tank C. a head tank D. a contraction tank 8. The high air velocity leaving the compressor of an exhaust gas turbocharger is converted to pressure in the . A. inlet nozzle ring B. turbine wheel blade C. diffuser passages D. inlet volute 9. is usually driven by the engine camshaft and supplies pilot air to the cylinder air start valve. A. An air receiver B. An operating valve C. An automatic valve D. An air distributor 10. Diesel engines driving alternators operating in parallel must maintain a set frequency regardless of load changes. The governor characteristic used to accomplish this is known as . A. actuation B. sensitivity C. compensation D. promptness 11. By comparing the exhaust gas temperature of each cylinder, the operator can determine if the load is balanced throughout the engine. The device most commonly used is a . A. tachometer B. pyrometer C. dynamometer D. calorimeter 12. When the ship is going to enter into the harbor, ____. A. change from heavy fuel oil to diesel oil for main engine B. pumping out bilge water C. change sea chest from high level one to lower level one D. test emergency generator 13. If the jacket water temperature rises rapidly above normal in a diesel engine, you should first . A. place standby cooler in operation B. reduce engine toad C. check thermostatic valve D. clean sea water strainer 14. Air cocks, usually positioned at the in a circulating system, is used to get rid of the air in the system. A. bending joint B. expansion tank C. weld D. the highest point 15. Which of the following conditions could contribute to the cracking of a diesel engine cylinder head? A. Leaking seal ring B. Insufficient heat transfer from the exhaust valves C. Blocked cooling water passages to the head D. Excessive scavenging air provided to the engine 16. of an engine crankshaft can be detected by measuring deflections of' crank webs for each unit of the engine. A. Misalignment B. Length C. Strength D. Stresses 17. can be a direct cause of faulty operation of diesel engine fuel injection nozzles. A. Excessive fuel nozzle holder cooling B. Sediment in the fuel supply C. Distortion of the fuel spray pattern D. Improper atomization of the fuel 18. When fuel is injected late into a diesel engine cylinder . A. the exhaust will be clear B. fuel consumption will be low C. all the fuel will be burned at top dead center D. fuel consumption will be high 19. A large change in ambient temperature, or using an oil of a viscosity different than the one recommended by the manufacturer in a mechanical hydraulic governor, will result m the need to adjust the . A. pilot valve opening B. compensating needle valve C. compensating spring tension D. accumulator spring tension 20. Which of the following factors tends to increase scale formation on the saltwater side of a heat exchanger used in a diesel engine cooling water system? A. Baffle plates that have been bent during prior removal. B. Leaks m the cooler tube nest. C. Operating the engine while maintaining a high sea water outlet temperature. D. A punctured sea water strainer supplying cooling water to the heat exchanger. 21. If the scavenge fire is of a more major nature, if there is a risk of the fire extending or if the scavenge trunk is adjacent to the crankcase with risk of a hot spot developing it sometimes becomes necessary to the engine. A. stop B. start C. speed up D. slow down 22. In an operating diesel engine, which of the following conditions is an indication of a leaking air starting valve?
Unit 1 罗素悖论的提出是基于这样的一个事例：设想有这样一群理发师，他们只给不给自己理发的人理发。假设其中一个理发师符合上述的条件，不给自己理发；然而按照要求，他必须要给自己理发。但是在这个集合中没有人会给自己理发。（如果这样的话，这个理发师必定是给别人理发还要给自己理发） 1901年，伯特兰·罗素悖论的发现打击了他其中的一个数学家同事。在19世纪后期，弗雷格尝试发展一个基本原理以便数学上能使用符号逻辑。他确立了形式表达式（如：x =2）和数学特性（如偶数）之间的联系。按照弗雷格理论的发展，我们能自由的用一个特性去定义更多更深远的特性。 1903年，发表在《数学原理》上的罗素悖论从根本上揭示了弗雷格这种集合系统的局限性。就现在而言，这种类型的集合系统能很好的用俗称集的结构式来描述。例如，我们可以用 x代表整数，通过n来表示并且n大于3小于7，来表示4，5,6这样一个集合。这种集合的书写形势就是：x={n：n是整数，3
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