单项选择题X 纠错
A.oxygen in the water
B.poor boiler design
C.density too high
D.excessive steam demand
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A.yellowish flame
B.golden yellow flame
C.white flame
D.brilliant white flame
单项选择题
A.condensate
B.a small amount of make-up feed
C.A and B
D.None of the above
单项选择题
A.yellowish flame
B.golden yellow flame
C.white flame
D.brilliant white flame
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A.low water level
B.low oil pressure
C.excessively high fuel pressure
D.an improper air/fuel ratio
单项选择题
A.Reciprocating pump
B.Screw pump
C.Diffuser pump
D.Water-ring pump
单项选择题
A.discharge is continuous
B.it has no internal valves
C.upon accidental closing of discharge valve, excessive pressure will not build up
D.all of the above are true
单项选择题
A.between the suction and discharge
B.below the liquid supply
C.above the liquid supply
D.any of the above
单项选择题
A.(1)only
B.(1)and(2)
C.(1),(2)and(3)
D.(2)and(3)
单项选择题
A.(1)only
B.(1)and(2)
C.(1),(2)and(3)
D.(2)and(3)
单项选择题
A.increased;decreased
B.decreased;increased
C.decreased;decreased
D.increased;increased