网友您好， 请在下方输入框内输入要搜索的题目：
题目内容
（请给出正确答案）
单选题
The most common cause of scale formation in an auxiliary boiler is （）
A
concentrations of calcium sulfate in the boiler water
B
fuel oil in the feed water
C
improper treatment of the feed water with calcium sulfate
D
excessive feed water alkalinity
参考答案
参考解析
解析：
暂无解析
更多 “单选题The most common cause of scale formation in an auxiliary boiler is （）A concentrations of calcium sulfate in the boiler waterB fuel oil in the feed waterC improper treatment of the feed water with calcium sulfateD excessive feed water alkalinity” 相关考题
考题
Earth－like planets are extremely common in the Universe, () the latest computer simulation of the formation of the Solar System.
A.according toB.in addition toC.in regard toD.thanks to
考题
●The error messages given by a C compiler show the message text,the most common cause of the error,and a suggestion for (73) the error.(73) A．upfsyingB．fixingC．changingD．Editing
考题
The type of installation “________” is selected by most users, the sof1be installed with the most common options.A.TypicalB.CompleteC.CustomD.Minimum
考题
Radio, telephone and press ____ of conveying news and information.
A.are the most three common meansB.are the most common three meansC.are the three most common meansD.are three the most common means
考题
The main propulsion diesel engine jacket water temperature rises above normal, with the raw sea suction and the expansion tank water level being normal. Which of the following problems is most likely the cause?A.Faulty thermostatic bypass valveB.Eroded zinc pencils in the heat exchangerC.Steam formation in the expansion tankD.Excessive leakage from jacket water pump seals
考题
The error messages given by a C compiler show the message text, the most common cause of the error, and a suggestion for(73)the error.A．updatingB．fixingC．changingD．Editing
考题
The type of installation“(71)”is selected by most users, the software installed with the most common options.A．TypicalB．CompleteC．CustomD．Minimum
考题
______ is the most common cause of ice formation．A.The freezing of raindrops on contact with the vessel's structureB.Drastic fall in ambient temperatureC.The deposit of water droplets on the vessel's structureD.Snowfall
考题
Which of the following is not the cause of the decrease in the oceanic salinity?___________A.Precipitation
B.Rain and snow
C.Formation of ice
D.Addition of water by rivers
考题
This question is about the formation of OSPF adjacency. An OSPF adjacency will not form correctly across a point-to-point link in the same area. Which would most likely cause this problem？（）A、Each interface has a different OSPF cost.B、Each interface is configured with secondary addresses as well as primary addresses.C、Each interface has a different MTU size.D、Each interface is configured with theip unnumbered loopback 0 command.
考题
单选题Excessive scale formation in a distilling plant may result from （）.A
poor distillate qualityB
reduced evaporator capacityC
low brine concentrationD
improper vacuum regulation
考题
单选题Worn main bearing will cause the compression ratio of an auxiliary diesel engine to（）A
increaseB
decreaseC
remain the sameD
increase on compression decrease on expansion
考题
单选题The purpose of treating the cooling water of the diesel engine is to（） Ⅰ. resist the scale formation in the cooling chamber Ⅱ.lubricate the engine part Ⅲ.increase thermal capacity Ⅳ.resist corrosionA
Ⅰ+ⅡB
Ⅱ+ⅢC
Ⅲ+ⅣD
Ⅰ+Ⅳ
考题
单选题Radio, television and press are ______ of conveying news and information.A
the most three common means B
the most common three meansC
the three most common means D
three the most common means
考题
单选题Waterside scale in a fire-tube boiler may cause （）.A
increased heat transferB
fireside erosionC
high steam demandD
overheated tubes
考题
单选题Which of the following may hardness of the boiler water cause?（） (1) scale formation (2) tube failure (3) corrosionA
（1）and（2）B
（1）and（3）C
（2）and（3）D
（1），（2）and（3）
考题
单选题For a flash type evaporator, the seawater heater will have to maintain a enough temperature to minimize scale formation（）A
lowerB
higherC
lowD
high
考题
单选题The main propulsion diesel engine jacket water temperature rises above normal, with the raw water sea suction and the expansion tank water level being normalWhich of the following problems is most likely the cause?（）A
Faulty thermostatic bypass valveB
Eroded zinc pencils in the heat exchangerC
Steam formation in the expansion tankD
Excessive leakage from jacket water pump seal
考题
单选题The most common cause of lowering the crankcase lube oil flash point is （）.A
more water contentsB
contamination with fuel oilC
higher temperatureD
sufficient cooling of oil mist
考题
单选题Moisture absorbed in the windings or condensed on the surface of electrical machinery insulation （）A
is good for long term preserving since most insulation is organic and contains some amountB
lowers the insulation value and is a common cause of fault grounds in idle machinesC
will enhance insulation resistance only if it is fresh water and contains no saltD
reduces the amount of current supplied or drawn by the machine so horsepower is limited
考题
单选题Excessive valve lash in an auxiliary diesel engine will cause the valves to open（）A
later and close soonerB
sooner and close laterC
sooner and close soonerD
later and close later
考题
单选题The star formation is most commonly used and requires（） on the alternator.A
one slip-ringB
two slipringsC
three slipringsD
four sliprings
考题
单选题An increase in the heat load to a refrigeration system will cause （）.A
the suction pressure to decreaseB
the suction temperature to increaseC
increased ice formation on the evaporator coilD
excessive short cycling of the compressor
考题
单选题Excessive alkalinity of the water in an auxiliary boiler can cause （）.A
caustic embrittlement of the boiler metalB
acidic corrosion of the boiler metalC
hard scale deposits on the boiler tubesD
etching of the heat exchange surfaces
热门标签
最新试卷
