【单选题】Which lubricating oil additive is used in diesel engines to reduce the tendency for sludge and varnish to form. on the engine parts?
【单选题】已知液化石油气气相的各组分质量成分为 在标准状态下的平均动力黏度为( )[各组分的动力黏度(10-6Pa.S)为:C3H8=7.65, C4H10=6.97]
【单选题】已知空气的密度ρ为1.205kg/m3,动力黏度(动力黏滞系数)μ为1.83×10-5Pa·s,那么它的运动黏度(运动黏滞系数)υ为( )。
【单选题】Sea water is not directly used as a coolant for engines because of its _____.
【单选题】已知空气的密度ρ为1.205kg/m 3 ,动力黏度(动力黏度系数)μ为1.83×10 - 5 Pa·s,那么它的运动黏度ν为( )。
【单选题】______ is a casing used for exhaust pipes from the engines.
【简答题】Unit 3 (Reading A) Match the business meals with their characteristics.A. breakfast meetingsB. breakfast meetingsC. lunchD. lunchE. afternoon tea or coffeeF. afternoon tea or coffeeG. dinnerH. dinner
【单选题】_____ the engines, the diesel engine is ____ used engine on board
A.
Between / more commonly
B.
Among / the most commonly
C.
Between / not more commonly
D.
Among / not the most commonly