单选题The ability of lubricating oils to resist viscosity changes during temperature changes is indicated by the（）A American PetroleumB Institute number viscosity index numberC Seconds Saybolt Furol numberD Seconds Saybolt Universal number

An additive used to improve the ability of a lube oil to reduce friction is known as a/an

A.suppressant additive

B.dispersant additive

C.extreme pressure additive

D.viscosity improver additive

Which of the following statements is correct regarding an oil with a high viscosity index?

A.A large change of viscosity occurs with a minor change in temperature

B.No change in viscosity occurs with any change in temperature

C.Very little change in viscosity occurs with a significant change in temperature

D.The viscosity of the oil increases with an increase in temperature

A diesel engine exposed to widely varying ambient temperatures should use to a lubricating oil with .

A.a high viscosity index

B.a low viscosity index

C.neutralize acids

D.resist oxidation at high temperatures

Since lubricating oils and jet fuels are acutely water critical，it is necessary to effect full line draining and mopping up of any water in tanks before loading ______．

A.purging with hydrocarbon gas

B.gas-freeing operations

C.maintaining an inert condition

D.full line draining and mopping up of any water

The ability of lubricating oils to resist viscosity changes during temperature changes is indicated by the ____.

A.American Petroleum

B.Institute number viscosity index number

C.Seconds Saybolt Furol number

D.Seconds Saybolt Universal number

The pour point of lubricating oils is affected the most by which of the following?

A.Extensive centrifuging

B.Wax content

C.Water content

D.Acid content

viscosity