2016年12月四级真题第三套段落匹配题SectionBDirections:Inthissection,youaregoingtoreadapassagewithtenstatementsattachedtoit.Eachstatementcontainsinformationgiveninoneoftheparagraphs.Identifytheparagraphfromwhichtheinformationisderived.Youmaychooseaparagraphmorethanonce.Eachparagraphismarkedwithaletter.AnswerthequestionsbymarkingthecorrespondingletteronAnswerSheet2.CanBurglarsJamYourWirelessSecuritySystem?A.Anyproductthatpromisestoprotectyourhomedeservescarefulexamination.Soitisn’tsurprisingthatyou’11findplentyofstrongopinionsaboutthepotentialvulnerabilitiesofpopularhome—securitysystems.B.Themostlikelytypeofburglary(人室盗窃)byfaristheunsophisticatedcrimeofopportunity,usuallyinvolvingabrokenwindoworsomeforcedentry.AccordingtotheFB1.crimesliketheseaccountedforroughlytwo.thirdsofallhouseholdburglariesintheUSin2013.Thewidemajorityoftherestwereillegal.unforcedentriesthatresultedfromsomethinglikeawindowbeingleftopen.TheoddsofacriminalusingtechnicalmeanstobypassasecuritysystemaresosmallthattheFBIdoesn’teventrackthosestatistics.C.Oneofthemaintheoreticalhome—securityconcernsiswhetherornotagivensystemisvulnerabletobeingblockedfromworkingaltogether.Withwiredsetups,thefearisthataburglar(人室盗贼)mightbeabletoshutyoursystemdownsimplybycuttingtherightcable.Withawirelesssetup.youstickbattery—poweredsensorsuparoundyourhomethatkeepaneyeonwindows。doors,motion,andmore.Iftheydetectsomethingwrongwhilethesystemisarmed.they’lltransmitawirelessaleftsignaltoabasestationthatwillthenraisethealarm.Thatapproachwilleliminatemostcord—cuttingconcerns--butwhatabouttheirwirelessequivalent,jamming?withthefightdevicetunedtothefightfrequency,what’stostopathieffromjammingyoursetupandblockingthatalertsignalfromeverreachingthebasestation?D.Jammingconcernsarenothingnew,andthey’renotuniquetosecuritysystems.Anydevicethat’sbuilttoreceiveawirelesssignalataspecificfrequencycanbeoverwhelmedbyastrongersignalcominginonthesamefrequency.Forcomparison.1et’ssayyouwantedto“jam”aconversationbetweentwopeople—allyou’dneedtodoisyellinthelistener’sear.E)Securitydevicesarerequiredtolistthefrequenciestheybroadcaston—matmeansthatapotentialthiefcanfindwhattheyneedtoknowwithminimalGoogling.Theywill.however.needtoknowwhatsystemthey’relookingfor.Ifyouhaveasigninyouryarddeclaringwhatsetupyouuse,that’dpointthemintherightdirection,thoughatthatpoint,we’retalkingaboutahighlytargeted,semi—sophisticatedattack,andnotthesortofforced—entryattackthatmakesupthemajorityofburglaries.It’seasiertofindandacquirejammingequipmentforsomefrequenciesthanitisforothers.F)Wirelesssecurityproviderswilloftentakestepstohelpcombatthethreatofjammingattacks.SimpliSafe,winnerofourEditors’Choicedistinction.utilizesaspecialsystemthat’scapableofseparatingincidentalRFinterferencefromtargetedjammingattacks.Whenthesystemthinksit’sbeingjammed,it’llnotifyyouviapushalert(推送警报).Fromthere,it’suptoyoutosoundthealarmmanually.G)SimpliSafewassingledoutinonerecentarticleonjamming,completewithavideoshowingtheentiresystembeingeffectivelybypassedwithhandheldjammingequipment.AftertakingappropriatemeasurestocontaintheRFinterferencetoourtestlab,wetestedtheattackoutforourselves,andwereabletoverifythatit’spossiblewiththerightequipment.However.wealsoverifiedthatSimpliSafe’santi-jammingsystemworks.Itcaughtusintheact,sentanalerttomysmartphone,andalsolistedourRFinterferenceonthesystem’seventlog.Theteambehindthearticleandvideoinquestionmakenomentionofthesystem,orwhetherornotitdetectedthem.H)Weliketheuniquenatureofthatsoftware.Itmeansthatathieflikelywouldn’tbeabletoGooglehowthesystemworks.thenfigureoutawayaroundit.Eveniftheycould,SimpliSafeclaimsthatitssystemisalwaysevolving,andthatitvariesslightlyfromsystemtosystem,whichmeanstherewouldn’tbeauniversalmagicformulaforcrackingit.Othersystemsalsoseemconfidentonthesubjectofjamming.TheteamatFrontpointaddressestheissueinablogonitssite,citingtheirownjamprotectionsoftwareandclaimingthattherearen’tanydocumentedcasesofasuccessfuljamattacksincethecompanybeganofferingwirelesssecuritysensorsinthel980s.I)Jammingattacksareabsolutelypossible.Assaidbefore.withthefightequipmentandtherightknow—how,it’spossibletojamanywirelesstransmission.Buthowprobableisitthatsomeonewillsuccessfullyjamtheirwayintoyourhomeandstealyourstuff?J)Let’simaginethatyouliveinasmallhomewithawirelesssecuritysetupthatoffersafunctionalanti—jammingsystem.First,athiefisgoingtoneedtotargetyourhome,specifically.Then,he’sgoingtoneedtoknowthetechnicaldetailsofyoursystemandacquirethespecificequipmentnecessaryforjammingyourspecificsetup.Presumably,youkeepyourdoorslockedatnightandwhileyou’reaway,sothethiefwillstillneedtobreakin.Thatmeansdefeatingthelocksomehow,orbreakingawindow.He’11needtobejammingyouatthispoint,asabrokenwindoworopeneddoorwouldnormallyreleasethealarm.S0,too,wouldthemotiondetectorsinyourhome,sothethiefwillneedtocontinuejammingoncehe’sinsideandsearchingforthingstosteal.However.he’11needtodosowithouttrippingtheanti-jammingsystem,thedetailsofwhichhealmostcertainlydoesnothaveaccessto.K)Attheendoftheday,thesekindsofsystemsareprimarilydesignedtoprotectagainstthesortofopportunisticsmash—and—grabattackthatmakesupthemajorityofburglaries.They’realsoonlyasinglelayerinwhatshouldideallybeamany—sidedapproachtosecuringyourhome,onethatincludescommonsensethingslikesoundlocksandproperexteriorlightingatnight.Nosystemisimpenetrable,andnonecanpromisetoeliminatetheworstcasecompletely.Everyoneofthemhasvulnerabilitiesthataknowledgeablethiefcouldtheoreticallyexploit.Agoodsystemisonethatkeepsthatworst—casesettingasimprobableaspossiblewhilealsoofferingstrongprotectionintheeventofaless-extraordinaryattack.--1.Itispossibleforburglarstomakejammingattackswiththenecessaryequipmentandskill.--2.Interferingwithawirelesssecuritysystemissimilartointerferingwithaconversation.--3.Aburglarhastocontinuouslyjamthewirelesssecuritydevicetoavoidtriggeringthealarm,bothinsideandoutsidethehouse.--4.SimpliSafeprovidesdevicesthatareabletodistinguishincidentalradiointerferencefromtargetedjammingattacks.--5.Onlyaverysmallproportionofburglariesarecommittedbytechnicalmeans.--6.ItisdifficulttocrackSimpliSafeasitssystemkeepschanging.--7.Wirelessdeviceswilltransmitsignalssoastoactivatethealarmoncesomethingwrongisdetected.--8.Differentmeasuresshouldbetakentoprotectone’shomefromburglaryinadditiontothewirelesssecuritysystem.--9.SimpliSafe’sdevicecansendawarningtothehouseowner’scellphone.--10.Burglarscaneasilygetasecuritydevice’sfrequencybyInternetsearch.
2016年12月四级真题第三套段落匹配题SectionBDirections:Inthissection,youaregoingtoreadapassagewithtenstatementsattachedtoit.Eachstatementcontainsinformationgiveninoneoftheparagraphs.Identifytheparagraphfromwhichtheinformationisderived.Youmaychooseaparagraphmorethanonce.Eachparagraphismarkedwithaletter.AnswerthequestionsbymarkingthecorrespondingletteronAnswerSheet2.CanBurglarsJamYourWirelessSecuritySystem?A.Anyproductthatpromisestoprotectyourhomedeservescarefulexamination.Soitisn’tsurprisingthatyou’11findplentyofstrongopinionsaboutthepotentialvulnerabilitiesofpopularhome—securitysystems.B.Themostlikelytypeofburglary(人室盗窃)byfaristheunsophisticatedcrimeofopportunity,usuallyinvolvingabrokenwindoworsomeforcedentry.AccordingtotheFB1.crimesliketheseaccountedforroughlytwo.thirdsofallhouseholdburglariesintheUSin2013.Thewidemajorityoftherestwereillegal.unforcedentriesthatresultedfromsomethinglikeawindowbeingleftopen.TheoddsofacriminalusingtechnicalmeanstobypassasecuritysystemaresosmallthattheFBIdoesn’teventrackthosestatistics.C.Oneofthemaintheoreticalhome—securityconcernsiswhetherornotagivensystemisvulnerabletobeingblockedfromworkingaltogether.Withwiredsetups,thefearisthataburglar(人室盗贼)mightbeabletoshutyoursystemdownsimplybycuttingtherightcable.Withawirelesssetup.youstickbattery—poweredsensorsuparoundyourhomethatkeepaneyeonwindows。doors,motion,andmore.Iftheydetectsomethingwrongwhilethesystemisarmed.they’lltransmitawirelessaleftsignaltoabasestationthatwillthenraisethealarm.Thatapproachwilleliminatemostcord—cuttingconcerns--butwhatabouttheirwirelessequivalent,jamming?withthefightdevicetunedtothefightfrequency,what’stostopathieffromjammingyoursetupandblockingthatalertsignalfromeverreachingthebasestation?D.Jammingconcernsarenothingnew,andthey’renotuniquetosecuritysystems.Anydevicethat’sbuilttoreceiveawirelesssignalataspecificfrequencycanbeoverwhelmedbyastrongersignalcominginonthesamefrequency.Forcomparison.1et’ssayyouwantedto“jam”aconversationbetweentwopeople—allyou’dneedtodoisyellinthelistener’sear.E)Securitydevicesarerequiredtolistthefrequenciestheybroadcaston—matmeansthatapotentialthiefcanfindwhattheyneedtoknowwithminimalGoogling.Theywill.however.needtoknowwhatsystemthey’relookingfor.Ifyouhaveasigninyouryarddeclaringwhatsetupyouuse,that’dpointthemintherightdirection,thoughatthatpoint,we’retalkingaboutahighlytargeted,semi—sophisticatedattack,andnotthesortofforced—entryattackthatmakesupthemajorityofburglaries.It’seasiertofindandacquirejammingequipmentforsomefrequenciesthanitisforothers.F)Wirelesssecurityproviderswilloftentakestepstohelpcombatthethreatofjammingattacks.SimpliSafe,winnerofourEditors’Choicedistinction.utilizesaspecialsystemthat’scapableofseparatingincidentalRFinterferencefromtargetedjammingattacks.Whenthesystemthinksit’sbeingjammed,it’llnotifyyouviapushalert(推送警报).Fromthere,it’suptoyoutosoundthealarmmanually.G)SimpliSafewassingledoutinonerecentarticleonjamming,completewithavideoshowingtheentiresystembeingeffectivelybypassedwithhandheldjammingequipment.AftertakingappropriatemeasurestocontaintheRFinterferencetoourtestlab,wetestedtheattackoutforourselves,andwereabletoverifythatit’spossiblewiththerightequipment.However.wealsoverifiedthatSimpliSafe’santi-jammingsystemworks.Itcaughtusintheact,sentanalerttomysmartphone,andalsolistedourRFinterferenceonthesystem’seventlog.Theteambehindthearticleandvideoinquestionmakenomentionofthesystem,orwhetherornotitdetectedthem.H)Weliketheuniquenatureofthatsoftware.Itmeansthatathieflikelywouldn’tbeabletoGooglehowthesystemworks.thenfigureoutawayaroundit.Eveniftheycould,SimpliSafeclaimsthatitssystemisalwaysevolving,andthatitvariesslightlyfromsystemtosystem,whichmeanstherewouldn’tbeauniversalmagicformulaforcrackingit.Othersystemsalsoseemconfidentonthesubjectofjamming.TheteamatFrontpointaddressestheissueinablogonitssite,citingtheirownjamprotectionsoftwareandclaimingthattherearen’tanydocumentedcasesofasuccessfuljamattacksincethecompanybeganofferingwirelesssecuritysensorsinthel980s.I)Jammingattacksareabsolutelypossible.Assaidbefore.withthefightequipmentandtherightknow—how,it’spossibletojamanywirelesstransmission.Buthowprobableisitthatsomeonewillsuccessfullyjamtheirwayintoyourhomeandstealyourstuff?J)Let’simaginethatyouliveinasmallhomewithawirelesssecuritysetupthatoffersafunctionalanti—jammingsystem.First,athiefisgoingtoneedtotargetyourhome,specifically.Then,he’sgoingtoneedtoknowthetechnicaldetailsofyoursystemandacquirethespecificequipmentnecessaryforjammingyourspecificsetup.Presumably,youkeepyourdoorslockedatnightandwhileyou’reaway,sothethiefwillstillneedtobreakin.Thatmeansdefeatingthelocksomehow,orbreakingawindow.He’11needtobejammingyouatthispoint,asabrokenwindoworopeneddoorwouldnormallyreleasethealarm.S0,too,wouldthemotiondetectorsinyourhome,sothethiefwillneedtocontinuejammingoncehe’sinsideandsearchingforthingstosteal.However.he’11needtodosowithouttrippingtheanti-jammingsystem,thedetailsofwhichhealmostcertainlydoesnothaveaccessto.K)Attheendoftheday,thesekindsofsystemsareprimarilydesignedtoprotectagainstthesortofopportunisticsmash—and—grabattackthatmakesupthemajorityofburglaries.They’realsoonlyasinglelayerinwhatshouldideallybeamany—sidedapproachtosecuringyourhome,onethatincludescommonsensethingslikesoundlocksandproperexteriorlightingatnight.Nosystemisimpenetrable,andnonecanpromisetoeliminatetheworstcasecompletely.Everyoneofthemhasvulnerabilitiesthataknowledgeablethiefcouldtheoreticallyexploit.Agoodsystemisonethatkeepsthatworst—casesettingasimprobableaspossiblewhilealsoofferingstrongprotectionintheeventofaless-extraordinaryattack.--1.Itispossibleforburglarstomakejammingattackswiththenecessaryequipmentandskill.--2.Interferingwithawirelesssecuritysystemissimilartointerferingwithaconversation.--3.Aburglarhastocontinuouslyjamthewirelesssecuritydevicetoavoidtriggeringthealarm,bothinsideandoutsidethehouse.--4.SimpliSafeprovidesdevicesthatareabletodistinguishincidentalradiointerferencefromtargetedjammingattacks.--5.Onlyaverysmallproportionofburglariesarecommittedbytechnicalmeans.--6.ItisdifficulttocrackSimpliSafeasitssystemkeepschanging.--7.Wirelessdeviceswilltransmitsignalssoastoactivatethealarmoncesomethingwrongisdetected.--8.Differentmeasuresshouldbetakentoprotectone’shomefromburglaryinadditiontothewirelesssecuritysystem.--9.SimpliSafe’sdevicecansendawarningtothehouseowner’scellphone.--10.Burglarscaneasilygetasecuritydevice’sfrequencybyInternetsearch.
比较C≡C, C=C, C─C, C=C─C=C的键长次序为: C=C─C=C>C─C> C≡C >C=C|C=C─C=C>C─C>C=C>C≡C|C≡C>C=C>C─C>C=C─C=C|C─C>C=C>C=C─C=C>C≡C|C─C>C=C─C=C>C=C>C≡C
比较C≡C, C=C, C─C, C=C─C=C的键长次序为: C=C─C=C>C─C> C≡C >C=C|C=C─C=C>C─C>C=C>C≡C|C≡C>C=C>C─C>C=C─C=C|C─C>C=C>C=C─C=C>C≡C|C─C>C=C─C=C>C=C>C≡C
下列哪种主链骨架原子排列最能代表两个肽键?() A: Cα—N—Cα—C—Cα—N—Cα—C B: Cα—N—C—C—N—Cα C: C—N—Cα—Cα—C—N D: Cα—C—N—Cα—C—N E: Cα—Cα—C—N—Cα—Cα—C
下列哪种主链骨架原子排列最能代表两个肽键?() A: Cα—N—Cα—C—Cα—N—Cα—C B: Cα—N—C—C—N—Cα C: C—N—Cα—Cα—C—N D: Cα—C—N—Cα—C—N E: Cα—Cα—C—N—Cα—Cα—C
比较C≡C(Ⅰ),C=C(Ⅱ),C─C(Ⅲ),C=C─C=C(Ⅳ)的键长次序为( )。 A: Ⅰ＞Ⅱ＞Ⅲ＞Ⅳ B: Ⅲ＞Ⅱ＞Ⅳ＞Ⅰ C: Ⅲ＞Ⅳ＞Ⅱ＞Ⅰ D: Ⅳ＞Ⅲ＞Ⅱ＞Ⅰ
比较C≡C(Ⅰ),C=C(Ⅱ),C─C(Ⅲ),C=C─C=C(Ⅳ)的键长次序为( )。 A: Ⅰ＞Ⅱ＞Ⅲ＞Ⅳ B: Ⅲ＞Ⅱ＞Ⅳ＞Ⅰ C: Ⅲ＞Ⅳ＞Ⅱ＞Ⅰ D: Ⅳ＞Ⅲ＞Ⅱ＞Ⅰ
不稳定的一类化合物是: C≡C|C－C|C＝C|C＝C－C＝C|C＝C＝C
不稳定的一类化合物是: C≡C|C－C|C＝C|C＝C－C＝C|C＝C＝C
NaNH4HPO4水溶液的质子条件式为 A: c(H+)+c(H2PO4-)+2 c(H3PO4)=c(OH-)+c(NH3) +c(PO43-) B: c(H+)+c(H2PO4-)+ c(H3PO4)=c(OH-)+c(NH3) +c(PO43-) C: c(H+)+c(NH3)+ c(H3PO4)=c(OH-)+c(PO43-) +c(H2PO4-) D: c(H+)+c(NH3)+ 2c(H3PO4)=c(OH-)+c(PO43-) +c(H2PO4-)
NaNH4HPO4水溶液的质子条件式为 A: c(H+)+c(H2PO4-)+2 c(H3PO4)=c(OH-)+c(NH3) +c(PO43-) B: c(H+)+c(H2PO4-)+ c(H3PO4)=c(OH-)+c(NH3) +c(PO43-) C: c(H+)+c(NH3)+ c(H3PO4)=c(OH-)+c(PO43-) +c(H2PO4-) D: c(H+)+c(NH3)+ 2c(H3PO4)=c(OH-)+c(PO43-) +c(H2PO4-)
比较C≡C(I)，C=C(II)，C─C(III)，C=C─C=C(IV)的键长次序为：
比较C≡C(I)，C=C(II)，C─C(III)，C=C─C=C(IV)的键长次序为：
在同一种固体介质中，纵波、横波、表面波三者之间的声速关系为（） A: C﹤C﹤C B: C﹤C﹤C C: C﹤C﹤C D: C﹤C﹤C
在同一种固体介质中，纵波、横波、表面波三者之间的声速关系为（） A: C﹤C﹤C B: C﹤C﹤C C: C﹤C﹤C D: C﹤C﹤C
scanf(“%c%c%c“, &a,&b,&c)与scanf(“%c %c %c“ ,&a,&b,&c)的输入（ ）。
scanf(“%c%c%c“, &a,&b,&c)与scanf(“%c %c %c“ ,&a,&b,&c)的输入（ ）。
能产生共轭效应的是 A: C=C=C B: C=C C: C≡C D: C=C-C=C E: C-C
能产生共轭效应的是 A: C=C=C B: C=C C: C≡C D: C=C-C=C E: C-C