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单选题
A vacuum is initially created in a flash type distilling plant by（）.
A
the flashing of the feed water
B
the condensation of the saltwater feed
C
air ejectors, eductors, or a separate vacuum pump
D
condensation of the distillate
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In your database, the flash recovery area (FRA) is configured as the default for RMAN backups. You executed the following commands to configure the settings in RMAN:Which statement is true about the outcome?（）A. Only one channel is allocated and the backup is created in the flash recovery areaB. Only one channel is allocated and the backup is created in the destination specified for channelC. Two channels are allocated and backup sets are created in the destinations specified for channels 1 and 2D. Three channels are allocated and backup sets are created in the destinations specified for channels 1, 2, and FRA
考题
In a flash type evaporator, all saltwater heaters are vented through individual vent cocks to the ______.A.saltwater heater shellB.second-stage condenserC.atmosphereD.second-stage flash chamber
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You decided to change the location of the flash recovery area. You executed the following command： ALTER SYSTEM SET DB_RECOVERY_FILE_DEST=’+disk1’ SCOPE=BOTH SID=’*’； Which statement is true？（）A、 The location can be changed only if the flash recovery area is empty.B、 After executing the command， all new flash recovery area files will be created in the new location.C、 The command will generate an error because you cannot change the flash recovery area while the database is open.D、 All the existing files in the flash recovery area will be moved to the new location and all new Flash Recovery Area files will be created in the new location.
考题
单选题One advantage of a flash distilling plant when compared to a submerged tube distiller is（）A
greater distillate purity through high temperature evaporationB
cold shocking for scale removal is not requiredC
less internal corrosion because of lower brine densityD
less feed-water is required for equal plant capacity
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The vacuum maintained in the salt water feed heater shell of a flash-type evaporator is generally accomplished by （）.A
a separate air ejector unitB
a direct unimpeded connection between second stage and salt water feed heaterC
either by vacuum drag or an external line from the first stage via a fixed orificeD
the fixed orifice provided in the steam supply line
考题
单选题You are using a radar in which your own ship is shown at the center，and the heading flash always points to 0°. If bearings are measured in relation to the flash，what type of bearings are produced? （）A
RelativeB
TRUEC
CompassD
Magnetic
考题
单选题In a flash type evaporator, all saltwater headers are vented through individual vent cocks to the（）.A
saltwater heater shellB
second-stage condenserC
atmosphereD
second-stage flash chamber
考题
单选题When distilling sea water the cooling water discharging from the distiller is fed back to evaporator as feed water （）.A
to decrease scale formationB
for better cooling effectC
for more economical purposeD
to raise vacuum
考题
单选题You decided to change the location of the flash recovery area. You executed the following command： Which statement is true？（）A
The location can be changed only if the flash recovery area is empty.B
After executing the command， all new flash recovery area files will be created in the new location.C
The command will generate an error because you cannot change the flash recovery area while the database is open.D
All the existing files in the flash recovery area will be moved to the new location， and all new Flash Recovery Area files will be created in the new location.
考题
单选题What is the operating principal of a flash type evaporator?（）A
Sea water is heated to boiling temperature under a vacuumB
Sea water is passed over heated plates in a thin filmC
Heated sea water is injected into a vacuum chamberD
Sea water is forced through a heated eductor
考题
单选题In the operation of a flash type evaporator equipped with air ejectors,the air and non- condensable gases are evacuated directly from the （）.A
first stage flash chamberB
second stage flash chamberC
first stage after condenserD
second stage distilling condenser
考题
单选题In your database, the flash recovery area (FRA) is configured as the default for RMAN backups. You executed the following commands to configure the settings in RMAN: RMAN CONFIGURE DEVICE TYPE disk PARALLELISM 2 BACKUP TYPE TO BACKUPSET; RMAN CONFIGURE CHANNEL 1 DEVICE TYPE disk FORMAT '/home/oracle/disk1/%U'; RMAN CONFIGURE CHANNEL 2 DEVICE TYPE disk FORMAT '/home/oracle/disk2/%U'; You issue the following RMAN command to backup the database: RMAN RUN 2 { 3 ALLOCATE CHANNEL ch1 DEVICE TYPE disk; 4 BACKUP DATABASE; 5 } Which statement is true about the outcome?（）A
Only one channel is allocated and the backup is created in the flash recovery areaB
Only one channel is allocated and the backup is created in the destination specified for channel 1C
Two channels are allocated and backup sets are created in the destinations specified for channels 1 and 2D
Three channels are allocated and backup sets are created in the destinations specified for channels 1, 2, and FRA
考题
单选题You decided to change the location of the flash recovery area. You executed the following command： ALTER SYSTEM SET DB_RECOVERY_FILE_DEST=’+disk1’ SCOPE=BOTH SID=’*’； Which statement is true？（）A
The location can be changed only if the flash recovery area is empty.B
After executing the command， all new flash recovery area files will be created in the new location.C
The command will generate an error because you cannot change the flash recovery area while the database is open.D
All the existing files in the flash recovery area will be moved to the new location and all new Flash Recovery Area files will be created in the new location.
考题
单选题The heated feedwater entering any flash chamber of a flash-type evaporator will（）A
vaporize, with the unflashed water remaining at the temperature at which it entered the flash chamberB
vaporize, with the unflashed water equalizing to the saturation conditions existing in the flash chamberC
vaporize, with the remaining water at the temperature greater than it entered the flash chamberD
boil, allowing steam bubbles to rise through the brine at the bottom of the flash chamber
考题
单选题For a flash type evaporator, a demister is located the condenser（）A
AfterB
beforeC
insideD
outside
考题
单选题In a flash type evaporator, the brine overboard pump is vented directly to the（）A
saltwater heater shellB
the condensation of the saltwater feedC
air ejectors, eductors, or a separate vacuum pumpD
condensation of the distillate
考题
单选题The advantages of flash type evaporators, as compared to submerged tube type evaporators, include （）.A
less internal corrosion because of lower brine densityB
higher temperature evaporation for lower salinity of the distillate producedC
less scale formation in a flash evaporatorD
less feed-water required for a flash evaporator
考题
单选题In the two stage flash distilling plant, which of the pumps listed is vented to the shell of the second stage in order to remove vapor from the pump suction?（）A
Condenser circulating water pumpB
Feed-water heater drain pumpC
Distillate pumpD
Air ejector condenser drain pump
考题
单选题Why will a two stage flash type distilling plant tend to operate more efficiently when operating in cold seawater?（）A
The colder seawater passing through the condenser tube bundles of the various stages increases evaporator vacuumB
The amount of heated feed water discharged from the feed water heater after cndenser is increasedC
Fewer non-condensable gases are created by the flow of colder seawaterD
More seawater is allowed to pass through the flint stage overflow weir
考题
单选题The crankcase of many diesel engines are kept under a slight vacuum by the （）.A
scavenging action of the pistonB
piston type vacuum pump taking suction off a differential manometerC
gland exhausting manometerD
crankcase exhaust fan
考题
单选题In （）, hot diesel engine jacket water passes over the stack and heats the sea water passing through the tubes.A
a flash generatorB
a flash evaporatorC
a vacuum boiling evaporatorD
a boiler
考题
单选题The second stage feed-water temperature and shell absolute pressure in a multistage, flash type, distilling plant is （）A
higher than the first stage feed-water temperature and absolute shell pressureB
lower than the first stage feed-water temperature and absolute shell pressureC
the same as the first stage feed-water temperature and absolute shell pressureD
not related to the feed-water temperature and absolute shell pressure
考题
单选题Which of the following descriptions best identifies the operating principal of a flash-type evaporator?（）A
Sea water is heated to boiling temperature while under a vacuumB
Sea water is passed over heated plates in a thin filmC
Heated sea water is injected into a vacuum chamberD
Sea water is forced through a heated eductor
考题
单选题Which one of the followings might not be employed to create vacuum for flash type evaporator? （）A
high-pressure steam-driven air-ejectorB
motor-driven vacuum pumpC
water-motivated air eductorD
centrifuge pump
考题
单选题In a flash distilling unit, evaporator feed (seawater) first absorbs heat in the （）.A
vapor feed heaterB
air ejector condenserC
saltwater heaterD
distillate cooler
考题
单选题A vacuum is initially created in a flash type distilling plant by（）.A
the flashing of the feed waterB
the condensation of the saltwater feedC
air ejectors, eductors, or a separate vacuum pumpD
condensation of the distillate
考题
单选题A vacuum is initially established in the first and second stages of a low pressure evaporator by the use of （）A
vacuum drag from the auxiliary condensate systemB
individual vacuum pumpsC
a single non-condensing air ejectorD
a two stage air ejector
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