一般来说,液体燃料的密度越大,闪点越低,而自燃点越高。
错误
易燃液体的燃点比闪点约高1~5℃,而闪点愈低,二者的差距愈小。苯、二硫化碳、丙酮等的闪点都低袭于0℃。在开口的容器中百作实验时,很难区别出它们的闪点与着火。可燃液体度中闪点在100℃以上者,燃点与闪点的差数可问达30℃或更高。
由于易燃液体的燃点与闪点很接近,所以在估计这类液体有火灾危险性时,只考虑闪点就可以了。一般来说,液体燃料的密度越小,闪点越低,而自燃点越高;液体燃料的密度越大,闪点越高,答而自燃点越低。
Inwhatseemsliketheprehistorictimesofcomputerhistory;theearth’spostwarera,therewasquiteawidespreadrumorthatcomputerswouldtakeovertheworldfrommanoneday.Alreadytoday,lessthanfiftyyearslater,ascomputersarerelievingusofmoreandmoreoftheroutinetasksinbusinessandinourpersonallives,wearefacedwithalessdramaticbutnotlessforeseenproblem.Peopletendtobeover-trustingofcomputersandarereluctanttochallengetheirauthority.Indeed,theybehaveasiftheywerehardlyawarethatwrongbuttonsmaybepushed,orthatacomputermaysimplymalfunction.Obviously,therewouldbenopointininvestinginacomputerifyouhadtocheckallitsanswers,butpeopleshouldalsorelyontheirowninternalcomputersandcheckthemachinewhentheyhavethefeelingthatsomethinghasgonewrong.Questioningandroutinedouble-checksmustcontinuetobeasmuchapartofgoodbusinessastheywereinpre-computerdays.Maybeeachcomputershouldcomewiththewarning:forallthehelpthiscomputermayprovide,itshouldnotbeseenasasubstituteforfundamentalthinkingandreasoningskills.
37.Accordingtothepassage,theauthorwouldprobablydisapproveof__________.
A.investmentincomputers
B.completedependenceoncomputers
C.double-checkoncomputers
D.theuseofcomputer
38.Intheauthor’sopinion,peopleshould__________.
A.bereasonablydoubtfulaboutcomputers
B.usecomputersforbusinesspurposesonly
C.substitutecomputersforbasicthinking
D.checkalltheiranswerswhenusingcomputers
39.Whatissuggestedinthispassage?
A.Computerwon’tchangeourpersonallives.
B.Computercancreateunforeseenproblems.
C.Computerhastakencontroloftheworld.
D.Computercannotaffectourbusinesses.
40.Whatisthemainpurposeofthispassage?
A.Tolookbacktotheearlydaysofcomputers.
B.Toexplainwhattechnicalproblemsmayoccurwithcomputers.
C.Todiscourageinvestmentincomputers.
D.Towarnagainstamentallylazyattitudetowardscomputers.