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简介：Thecharacterizationmadtestingmethodsofthedynamicfractureinitiationtoughnessofelas-tic-plasticmaterialsundertensileimpactarestudied.Byusingtheself-designedbar-bartensileimpactappa-ratus,anoveltestmethodforstudyingdynamicfracture-initiationhasbeenproposedbasedontheone-di-mensionaltestprinciple.Thecurveofaverageloadv.s.displacement（-δ）issmoothuntilunstablecrackpropagation,andthekineticenergywhichdoesnotcontributetothecrackgrowthcanberemovedfromtotalworkdonebyexternal-forcetothespecimen.Thefracture-initiationpointisdeterminedbycompliance-changingratemethod.Theresultsshowthatthesemethodsarefeasibleandeffective.Throughtheanalysisoftheconversionbetweenworkandenergyofafracturespecimen,thedynamicJ-integralisadoptedasachar-acteristicparameterforelastic-plasticmaterialsunderimpactloading.TheJ-integraliscalculatedfrom-△andP-δcurvesbyusingtheformulaproposedbyRice.TheJ-integralatfractureinitiationisemployedtodescribethedynamicfracture-initiationtoughnessofelastie-plasticmaterialsandtheexperimentalresultsindicatethatJ10canberegardedasamaterialconstant.

简介：Insituchemicaloxidationpolymerizationofpyrroleonthesurfaceofsulfurparticleswascarriedouttosynthesizeasulfur/polypyrrole(S/PPy)nanocompositewithcore-shellstructure.Thecompositewascharacterizedbyelementalanalysis,X-raydiffraction,scanning/transmissionelectronmicroscopy,andelectrochemicalmeasurements.XRDandFTIRresultsshowedthatsulfurwelldispersedinthecore-shellstructureandPPystructurewassuccessfullyobtainedviainsituoxidativepolymerizationofpyrroleonthesurfaceofsulfurparticles.TEMobservationrevealedthatPPywasformedandfixedtothesurfaceofsulfurnanoparticleafterpolymerization,developingawell-definedcore-shellstructureandthethicknessofPPycoatinglayerwasintherangeof20-30nm.Inthecomposite,PPyworkedasaconductingmatrixaswellasacoatingagent,whichconfinedtheactivematerialswithintheelectrode.Consequently,theaspreparedS/PPycompositecathodeexhibitedgoodcyclingandrateperformancesforrechargeablelithium/sulfurbatteries.TheresultingcellcontainingS/PPycompositecathodeyieldsadischargecapacityof1039mAhg-1attheinitialcycleandretains59%ofthisvalueover50cyclesat0.1Crate.At1Crate,theS/PPycompositeshowedgoodcyclestability,andthedischargecapacitywas475mAhg-1after50cycles.

简介：Inthispaper,withK+,Ca2+andFe3+astheobjectsofstudy,retardationofsoil–bentonite(SB)barriermaterialsformetalionswithdifferentvalencesisinvestigated,andtheadsorptionmechanism,migrationpatternsandpermeationbehaviorareexploredsoastoprovideatheoreticalbasisfortheirapplication.TheresultsshowthattheadsorptionprocessformetalionswithdifferentvalencesbySBbarriermaterialsisfast,andthehigherthevalence,thegreatertheadsorptioncapacity.Thefttingoftheadsorptionprocessconformstopseudo-second-orderadsorptionkineticsandLangmuir–Freundlichadsorptionequation,whichexplainsthatchemicaladsorptionisthedominatingstateandthattheSBsurfacehascertainheterogeneity.ThepermeabilitycoeffcientofK+,Ca2+andFe3+inSBeachhasamaximumandthehigherthevalence,thesoonerthemaximumappears.Alsothehigherthevalence,themoreobvioustheeffectonSBretardationperformance;andthesoonertheionbreaksthroughthebarrierwallcompletely,thatis,thewall’sretardationperformanceforhighervalentionsmaydecline.

简介：Thispaperdealswiththecombinationofpointphononandphasonforcesappliedintheinteriorofinfiniteplanesandhalf-planesof1Dquasicrystalbi-materials.Basedonthegeneralsolutionofquasicrystals,aseriesofdisplacementfunctionsareadoptedtoobtainGreen'sfunctionsforinfiniteplanesandbi-materialplanescomposedoftwohalf-planesintheclosedform,whenthetwohalf-planesaresupposedtobeideallybondedortobeinsmoothcontact.Sincethephysicalquantitiescanbereadilycalculatedwithouttheneedofperforminganytransformoperations,Green'sfunctionsareveryconvenienttobeusedinthestudyofpointdefectsandinhomogeneitiesinthequasicrystalmaterials.

简介：HighZandlowZmaterialsareboththecandidateplasmafacingmaterials(PFM),uptonow,thetypicalrepresentativeofhighZmaterialsistungsten,andtherepresentativesoflowZmaterialsarecarbonmaterials(suchasgraphite,C/Ccomposite)andberyllium.MostofthesematerialshavebeenusedasPFMlimitersanddiverterarmortilesoftokamakmachines,tungsten,molybdenumandC/Ccompositearealwaysusedashighheatfluxcomponents.

简介：Inthispaper,theKirchhoffstransformationispopularizedtothenonlinearheatconductionproblemwhichtheheatconductivitycanbeexpressdasamultinomialoftemperaturefirstly,theboundaryconditionofheatconductionproblemisdeterminedbyanalytics.Secondly,theincubationperoidsuperpositionandthelinearcombinationlawisemployedtosimulatethetransientphassestransformationintheprocessofheattreatmentofmaterials.Thatthebegintimeofphasetransformation,thetypeofphasetransformationandtheamountofphaseconstitutionisdeterminedsimply.Finally,thethree-dimensionDualReciprocityBoundaryElementMethodisusedtoanalysisthetotalprocessofvariousheattreatmentofcomponent,theresultsofnumericalcalculationofexamplesshowthatthemethodprovidedinthispaperiseffectivce.

简介：Themechanismsofinterracialdebondingofparticlereinforcedtheologicalmaterialsarestudied.Basedonanenergycriterion,asimpleformulaoflocalcriticalstressforinterfacialdebondingisderivedandexpressedintermsoftheinterfacialenergy.Theparticlesizeeffectoninterfacedebond-ingcanthenbeanalyzedeasilyowingtothefactthatcriticalstressisinverselyproportionaltothesquarerootofparticleradius.BytakingPP/CaCO3systemasanexample,thepresentenergycriterioniscomparedwiththemechanicaldebondingcriterion,anditisfoundthatundertheconditionthatbondstrengthisequaltomatrixstrengthandparticleradiusnotover0.2μm,themechanicaldebondingcri-terioncanbeautomaticallysatisfiediftheenergycriterionissatisfied.Arelationbetweencriticaltimeandinterfaceenergyiscalculatedbyusingtheenergycriterion.Theinfluencesoftheparticlevolumefractionandtheparliclesize,theloadingrateandtherelaxationtimeofthematrixonthecriticaltimeofinterfacialdebondingarealsodiscussed.

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简介：Two-dimensional(2D)metalcarbides,MXene,presentthepromisingapplicationfortheenergystoragesystem.AmongtheMXenefamily,Ti2CTxasthelightestmaterial,showsitsuniqueelectrochemicalperformance.Herein,Ti2CTxissynthesizedbyselectiveetchingAllayerfromtheTi2AlC.WiththeoptimizedHFtreatingcondition,Ti2CTxdisplayshighvolumetriccapacitaneeandremarkablerateability.Moreover,theTi2CTx//Ti2CTxsymmetricsupercapacitorisdesignedandassembled,whichpresentscapablecapacitance,outstandingrateperformanceandexcellentcyclingperformance.Theremarkableelectrochemicalperformanceisattributedtoits2Dstructureandhighelectronicconductivity.ThisworkdemonstratesthepotentialapplicationoftheTi2CTxforthesupercapac让o「sandprovidesatemplatetodesignhighperformancesupercapacitorswith2Delectrodematerials.

简介：Theexistingabsorptioncoefficientmeasurementinawatertubeislimitedinlowfrequencyduetothelimitationofthepulsetubelength.Awide-bandpulsetubemethodbasedonthepost-processinginversefilterisproposed.Afterobtainingtheresponseoftheentiresystem,thetransducerisexcitedwithwide-band,short-durationsignals.Then,thereceivedsignalsareprocessedwithinversefiltersandthe'blurred'reflectivesignalsofstandardreflectorandtestsamplearerecoveredrespectively,finally,thereflectioncoefficientandabsorptioncoefficientarecalculated.Simulationworkisimplementedtoverifytheadvantageofpostprocessinginversefilteroverpre-processinginversefilterintermsoflowfrequencymeasurement.Toverifytheproposedmethod,twodifferentwide-bandpulsesintheseparatefrequencyrangesareadoptedtomeasurethesamerubbermaterial.Theexperimentalresultsindicatethatthewide-bandpulsemethodandCW(ContinuousWave)pulsemethodhavegoodagreementinbothlowfrequencyrangeandhighfrequencyrange.Wide-bandpulsemethodisofhighefficiency,andthelowfrequencyreaches350Hz,whichisabletoextendthelowfrequencyrange.

简介：Pillar[n]arenesareanewkindofsupramolecularmacrocyclichostswhichhavedevelopedrapidlyduetotheiruniquetopologyandhighfunctionality,givingrisetomanyapplicationsintheconstructionofinterestingandfunctionalmaterials.Amongthem,water-solublepillar[n]arenesbearingtriethyleneoxide(TEO)chainshavedrawnincreasingresearchinterestduetotheiradvantageousproperties.Inthisreview,wesummarizedtherecentprogressofdynamicmaterialsfabricatedfromwatersolublepillar[n]arenesbearingTEOgroups,includingthermoresponsivematerialswithlowercriticalsolutiontemperature(LCST)behavior,cyclichostliquids,andsmartwindows.Itisanticipatedthatmoreandmore‘smart’supramolecularmaterialsbasedonmodifiedpillar[n]areneswillbedevelopedinthisburgeoningareaofresearch.

简介：4-hydroxy-4'-nitroazobenzene(NHA)and4-amino-4'-nitroazobenzene(DO3)werepreparedrespectivelyfromp-nitrophenylamineasaprecursorcompound.Twokindsofdopedorganic/inorganichybridnonlinearoptical(NLO)materialscontainingNHAandDO3weresynthesizedbySol-Gelprocess.ThepreparationandpropertiesoftwoNLOmaterialswerestudiedandcharacterizedbyFTIR,1H-NMR,UV-VIS,SEM,DSCandSHGmeasurements.TheresultsshowthatthemaximumdopingamountsofNHAandDO3intwodopedhybridNLOmaterialsare7.2(wt)%and11.3(wt)%respectively,andthecorrespondingsecond-orderNLOcoefficients(d33values)are2.91×10-8esuand6.14×10-8esu.TwodopedNLOmaterialshaverelativelygoodRTstability,after90daysatRTthed33valuescanmaintainabout85%oftheirinitialvalues,butafter10hat100℃canonlymaintainabout50%oftheirinitialvalues.Inthisreport,thereasonsforhigh-temperatureinstabilityofdopedmaterialswerediscussed,andthepossibleimprovementswerealsosuggested.

简介：Carbon-basematerialswillbemajorplasmafacingmaterials(PFM)inafusiondeviceinneartermandeveninthefutureinspiteofitshightritiumtrappingandchemicalsputteringyield.Ofcourse,thedevelopmentofhighZPFMandfreesurfacesystemarealsoimportantforfusionenergy.

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简介：裂缝的一个二倍地周期的数组在远地的反飞机下面削弱的Orthotropic材料砍被调查，在基本房间包含不相等的尺寸的四个裂缝的地方。由使用印射的技术，椭圆的函数理论和分析函数边界值问题的理论，整个地的压力的一个关上的形式解决方案被获得。为在裂缝尖端和有效的反飞机的压力紧张因素的准确公式砍击碎的orthotropic材料的模量被导出。有有限元素方法的比较显示出现在的方法的效率和精确性。几个解说性的例子被提供，并且有趣的现象也就是说被观察更少的有效模量是的压力紧张因素和尺寸独立于为二倍地周期的击碎的各向同性的材料的材料性质，但是为二倍地周期的击碎的orthotropic材料强烈取决于材料性质。为反飞机问题的如此的现象为在里面飞机问题类似于那。现在的答案能为另外的数字、近似的方法提供基准结果。

简介：Wereportasimplesolution-processedmethodforthefabricationoflow-cost,flexibleopticallimitingmaterialsbasedongrapheneoxide(GO)impregnatedpolyvinylalcohol(PVA)sheets.SuchGO–PVAcompositesheetsdisplayhighlyefficientbroadbandopticallimitingactivitiesforfemtosecondlaserpulsesat400,800,and1400nmwithverylowlimitingthresholds.Femtosecondpump–probemeasurementresultsrevealedthatnonlinearabsorptionplayedanimportantrolefortheobservedopticallimitingactivities.Highflexibilityandefficientopticallimitingactivitiesofthesematerialsallowthesecompositesheetstobeattachedtononplanaropticalsensorsinordertoprotectthemfromlight-induceddamage.

简介：ActivatedcarbonsforelectrochemicalcapacitorelectrodesarepreparedfromsoyabeanusingchemicalactivationwithKOH.TheporesizeiseasilycontrollablebychangingthemassratiobetweenKOHandcarbonizedproduct.Theas-preparedmaterialspossessalargespecificsurfacearea,uniquestructure,well-developedhierarchicalporosityandplentifulheteroatoms(mainlyOandN).Thusresultedinitshighspecificcapacitance,goodratecapacityandcyclingstability.Moreover,attributingtoworldwideavailability,renewablenatureandlow-cost,activatedcarbonpreparedfromsoyabeanhasagoodpotentialinenergyconversionandstoragedevices.

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