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單項(xiàng)選擇題

Oxygen corrosion in auxiliary boilers is prevented by treating the boiler feed tank with either sodium （）

A.sulfite or hydrazine
B.sulfite or hygroscopic sulfite
C.bromide or hydrazine
D.bromide or hygroscopic sulfite

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單項(xiàng)選擇題

Operating a diesel engine for prolonged periods, with a closed freshwater cooling system, at temperatures lower than the normal design temperature can cause （）.

A.the formation of sulfuric acid
B.a decrease in lube oil viscosity
C.a decrease in cooling water pH
D.a thermostat failure

單項(xiàng)選擇題

Improper maintenance of the fuel oil burners in an automatically fired auxiliary boiler, could result in （）

A.increased fuel consumption
B.increased feed water consumption
C.fuel pump failure
D.combustion control system failure

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