简介：DifferentmodelshavebeenproposedfortheformationandtectonicevolutionoftheSouthChinaSea(SCS),includingextrusionoftheIndochinaPeninsula,backarcextension,two-stageopening,proto-SCSdragging,extensioninducedbyamantleplume,andintegratedmodelsthatcombinediversefactors.Amongthese,theextrusionmodelhasgainedthemostattention.Basedonsimpli?edphysicalexperiments,thismodelproposesthatcollisionbetweentheIndianandEurasianPlatesresultedinextrusionoftheIndochinaPeninsula,whichinturnledtoopeningoftheSCS.TheextrusionoftheIndochinaPeninsula,however,shouldhaveledtopreferentialopeninginthewestsideoftheSCS,whichiscontrarytoobservations.ExtensionalmodelsproposethattheSCSwasabackarcbasin,riftedofftheSouthChinaBlock.Mostofthebackarcextensionmodels,however,arenotcompatiblewithobservationsintermsofeitherageorsubductiondirection.Thetwo-stageextensionmodelisbasedonextensionalbasinssurroundingtheSCS.Recentdatingresultsindeedshowtwo-stageopeningintheSCS,buttheSouthwestSubbasinoftheSCSismuchyounger,whichcontradictsthetwo-stageextensionmodel.Hereweproposeare?nedbackarcextensionmodel.TherewasawideNeotethysOceanbetweentheAustralianandEurasianPlatesbeforetheIndian-Eurasiancollision.Theocean?oorstartedtosubductnorthwardat*125Ma,causingbackarcextensionalongthesouthernmarginoftheEurasianPlateandtheformationoftheproto-SCS.TheNeotethyssubductionregimechangedduetoridgesubductionintheLateCretaceous,resultinginfold-belts,uplifting,erosion,andwidespreadunconformities.Itmayalsohaveledtothesubductionoftheproto-SCS.FlatsubductionoftheridgemayhavereachedfurthernorthandresultedinanotherbackarcextensionthatformedtheSCS.Therollbackofthe?atsubductingslabmighthaveoccurred*90Maago;thesecondbackarcextensionmayhaveinitiatedbetween50and45Ma.TheopeningoftheSouthwestSub

简介：StraightandBentnano-cantileverspecimensarerespectivelyproposedtoinvestigatethesingle-modeandmixed-modecrackinitiationattheCu/Siinterfaceedgeinnanoscalecomponents.Withaminuteloadingapparatus,allnanoscalesamplesareinsituloadedandobserved.Numericalanalysisisemployedtoacquirethecriticalinterfacialstressdistributionsduringcrackinitiation.ThestressconcentrationregionsneartheedgeofCu/Siinterfaceinallspecimensarewithinthescaleof100nm,andthecriticalnormalandshearstresseshaveacircularrelationinnanoscalecomponents,whichrepresentsthefracturecriterionoftheinterfaceinnanoscalecomponents.