恒定干燥介质条件下,降速干燥阶段的湿料表面温度为湿球温度。
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空气的干球温度和湿球温度相差越大,说明该空气偏移饱和程度就越大。
在恒速干燥阶段所除去的水分是非结合水和部分结合水。
Youareworkinginanonlinetransactionprocessing(OLTP)environment.YouusedtheFLASHBACKTABLEcommandtoflashbacktheCUSTOMERStable.BeforeexecutingtheFLASHBACKTABLEcommand,theSystemChangeNumber(SCN)was663571.AfterflashingbacktheCUSTOMERStable,yourealizethatthetableisnotinthecorrectstateandtheresultantchangesarenotwhatyouhaddesired.So,youneedtoreversetheeffectsoftheFLASHBACKTABLEcommandwhileensuringthat:
a)Nootheruserdatainthedatabaseisaffected.
b)Theoperationtakestheminimumpossibletime.
Whichoptionwouldyouchoose?()