Besides heat, fuel, and oxygen, which of the following is necessary for a fire to exist?（）

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• The rate of heat transfer between the hot and cold fluids passing through a shell-and-tube type heat exchanger will （）.

  A . remain constant along the tubes length B . be greatest in a single pass counter flow heat exchanger C . remain constant throughout the heat exchanger D . vary from section to section through out the heat exchanger

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• The vapors given off by heated fuel oil are flammable, explosive, and （）

  A . lighter than air B . heavier than air C . odorless D . nontoxic

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• Heat damage to fuel injection nozzles can be prevented by avoiding （）

  A . excessive fuel oil temperature B . long periods of engine overload C . metallic contact between nozzles and cylinder heads D . hard carbon deposit and varnish on the nozzle

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• In a diesel engine, the time taken to heat the fuel particles, turn them into vapor, and bring about combustion is called （）

  A . injection lag B . ignition delay C . compression D . turbulence lag

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• The treatment of the fuel oils involves storage, heating, filtering and（）

  A . centrifuging B . pressurizing C . atomization D . igniting

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• The vapors given off by heated fuel oil are heavier than air and are（）.

  A . odorless B . explosive C . nontoxic D . visible

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• Heat for igniting the fuel oil in the cylinder of a diesel engine is generated by the （）

  A . electronic ignition system B . compression of air by the piston C . friction in the fuel injector D . fuel oil bearing system

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• The rate of expansion of heated fuel oil varies with the （）.

  A . conductivity B . viscosity C . volume D . specific gravity

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• Diesel fuel is relatively safe to handle due to its low volatility, but the fumes will self-ignite and continue to burn steadily if the fuel is heated to the （）.

  A . flash point B . auto-ignition point C . volatility point D . upper explosive limit

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• Fuel injection systems meter fuel, atomize fuel, and （）.

  A . create turbulence in the combustion chamber B . aid in completing cylinder scavenging C . inject fuel at the proper time D . minimize fuel penetration into the cylinder

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• Heat damage to fuel injection nozzles on small high-speed diesel engines, can be prevented by（）

  A . employing fuel oil as a cooling medium B . preventing hard carbon deposit on nozzle tips C . avoiding fuel oil temperature exceeding builder’s specification D . ensuring good metallic contact between nozzles and cylinder head

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• Heavy residual fuel oils are heated prior to centrifuging to （）

  A . reduce fuel weight B . increase specific gravity C . separate fuel from lube oil D . reduce fuel viscosity

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• What is required in addition to the heat，fuel，and oxygen of the fire triangle to have a fire?（）

  A . Electricity B . Chain reaction C . Pressure D . Smoke

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• The burning of the fuel adds more heat to the air charge, causing it to expand and force the engine piston to do work on the crankshaftWhat does “it” mean in this sentence?（）

  A . the burning B . the fuel C . the air charge D . the engine pisto

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• The flash point of a residual fuel oil should be used to determine the highest temperature to which oil may be heated （）

  A . for atomizing B . for centrifuging C . in a storage tank D . in the re-circulating line

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• In a typical fuel oil system, the oil is stored in tanks in the double bottom from which it is pumped to （） and heated.

  A . a service tank B . a collecting tank C . a sump D . a settling tank

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• Besides Buddhism and Shamanism , do the Mongolians worship their ancestor Chingis Khan ?

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• ◑Cold and dry.◑Humidity and heat.◑Light rain.◑Variation.

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• When the heavy fuel oil is heated to achieve the viscosity of 10-15 cSt, may occurTo 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

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• English ______ in many countries besides the UK and the US.

  A．speaks B．has spoken C．is spoken

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• Some policymakers believe that bio-fuel could help to save American farm, besides relieving pressure on______.

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• Besides giving, love _______ such elements as care, responsibility, respect and knowledge.

  A．composes of B．makes up of C．makes from D．consists of

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• In some ways, the human body is both like a furnace and like an engine. It must have fuel to produce heat as a furnace【C1】______. It must have fuel to produce motion and do【C2】______as an engine does. The nutrients(营养物)which【C3】______energy best are carbohydrates(碳水化合物)and fats. Protein can also be used as fuel. Minerals, vitamins, and water,【C4】______extremely valuable to the body, cannot be used as fuel.

  If the body takes in more carbohydrates【C5】______are used for energy, the【C6】______is stored. Two storage places are the liver(肝)and muscles. There is a【C7】______, however, to the amount of carbohydrates they can【C8】______. When they are filled and they always【C9】______be for you to feel your best, excess carbohydrates are changed to fat and【C10】______around the body. If the body does not take【C11】______a sufficient amount of food, it will use its stored fat for energy. If you【C12】______at all, the body would use up all the stored fats and【C13】______it would use its own protein in order to keep【C14】______as long as possible. Therefore, the【C15】______amount of food you eat should be in【C16】______with your energy requirements. It is not necessary,【C17】______, for you to go【C18】______counting calories(卡路里)and weighing food. If a person is the【C19】______weight, it is safe to【C20】______that he is eating enough. 【C1】 A．has B．needs C．does D．is

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• Nurse: Besides the diet, you need to do mild （)（运动)and keep in good mood.In this wa

  A．In this way you will get well very soon. B．exercises C．sighing D．framework E．disable person

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