Combustion knock can occur in the cylinders of a diesel engine under any condition permitting （）.

[单选题]How does combustion air enter the cylinder of a two-cycle diesel engine?（）A . Cylinder head valvesB . PortsC . Turbo chargersD . Bleeder valve

[单选题]C．ombustion knock occurring in a diesel engine can be caused by _____.A．low coolant temperatureB．insufficient fuelC．high ambient temperatureD．carbon buildup on the injector tips

[单选题]Combustion knock occurring in a diesel engine can be caused by （）.A . excessive fuel penetrationB . prolonged injection lagC . reduced ignition lagD . prolonged ignition lag

[单选题]Poor combustion in a diesel engine can be caused by （）.A . high compression pressureB . low intake air temperatureC . low exhaust pressureD . high scavenge air pressure

[单选题]A．ccording to this passage, if the cylinder non-return valve were not leakyA．an explosion would not be causedB．there still would be a danger of explosionC．oil would not deposit in the air pipeD．pipe lines would not have to be drained

[名词解释] knock out（基因敲除）

[名词解释] 心包叩击音（pericardial knock）

[单选题]Theoretical perfect combustion in a diesel engine yields by-products of_____.A．aldehydes and carbon dioxideB．water vapor and carbon monoxideC．nitrogen and carbon monoxideD．water vapor and carbon dioxide

[单选题]If the flame from combustion in the cylinder of a four-stroke engine past the piston into the space below, the accumulation of flammable mixture would be ignited, thus resulting in _____.A．the crankcase explosionB．lifting of the cylinder safety valve

[单选题]Fuel is delivered into the combustion space by （）.A . a cooling systemB . a lubricating systemC . an electric systemD . an injection system