Excessivealkalinityofthewaterinanauxiliaryboilercancause().
A. causticembrittlementoftheboilermetal
B. acidiccorrosionoftheboilermetal
C. hardscaledepositsontheboilertubes
D. etchingoftheheatexchangesurfaces
公司初次发行公司债券,其资产总额为20000万元,负债总额为15000万元,则其累计发行债券总额不应超过()
A. 8000万元
B. 5000万元
C. 2000万元
D. 3000万元
Whichofthefollowingconditionsmayneedtobereducedwhenoperatingalarge,lowspeed,mainpropulsion,dieselengineatlowloads?()
A. Injectionpressures
B. Controlairsupplypressure
Coolingwaterflowthroughafter-coolers
D. Lubeoiltemperature
Oxygencorrosioninauxiliaryboilersispreventedbytreatingtheboilerfeedtankwitheithersodium()
A. sulfiteorhydrazine
B. sulfiteorhygroscopicsulfite
C. bromideorhydrazine
D. bromideorhygroscopicsulfite