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简介:粉状的LiCr0.35Mn0.65O2的电的传导性在温度范围在高压力下面被测量直到26.22GPa由使用一个钻石铁砧房间的300413K。电导率和激活热含量在5.36GPa和21.66GPa不连续地变化,这被发现。在压力范围1.105.36GPa,压力增加激活热含量并且减少散布的搬运人,它最后导致传导性增加。在压力范围6.3221.66GPa和22.6026.22GPa,有压力增加的激活热含量减少,它有积极贡献到电的电导率增加。二导致压力的结构的阶段转变被发现由在原处在高压力下面X光检查衍射,它导致电导率和激活热含量的不连续的变化。
简介:Veryhighcyclefatiguebehaviorsoftwobainite/martensitedual-phasesteelswereinvestigated.Oneofthesteelswascyclicrapidheattreatedanditsmicrostructureswererefined.Fatiguestrengthofthesteelis225MPahigherthanthatwithoutrefining.Observationoffracturesurfacesshowthatthefatiguecracksinitiateatbainitesfornon-refinedsteelandatnon-metallicinclusionsfortherefinedsteel.Thesizeofinclusionsismuchsmallerthanthatofbainiteswhichresultsintheimprovementoffatiguestrength.
简介:InsituhighpressureenergydispersiveX-raydiffractionmeasurementsonlayeredperovskite-likemanganateCa3Mn2O7underpressuresupto35GPahavebeenPerformedbyusingdiamondanvilcellwithsynchrotronradiation.Theresultsshowthatthestructureoflayeredperovskite-likemanganateCa3Mn2O7isunstableunderpressureduetotheeasycompressionofNaCl-typeblocks.ThestructureofCa3Mn2O7underwenttwophasetransitionsunderpressuresintherangeof0-35GPa.Onewasatabout1.3GPawiththecrystalstructurechangingfromtetragonaltgoorthorhombic.Theotherwasatabout9.5GPawiththecrystalstructurechangingformorthorhombicbacktoanothertetragonal.
简介:Thethree-phasesbehaviorinthequaternarystsemofn-dodecylpolyglucosideC12G1.46/1-butanol/cyclohexane/waterhasbeenstudiedat40℃intermsofthevariablesγandδ.Increasingδatconstantγcausesaphaseinversionfromanoil-in-watermicroemulsionincontactwithexcessoil(winsorIor2)toawater-in-oilmicroemulsionincontactwithexcesswater(winsorⅡor2)viaamiddle-phasemicroemulsionincontactwithexcessoilandwater(winsorⅢor3).Bytakingintoaccountthedifferentsolubilitiesofalkylpolyglucosideand1-butanolintheoilphase,thecompositionofthehydrophile-lipophilebalancedinterfacialfilminthemiddleofthethree-phasebodycanbecalculated.Theeffectsofdifferentoilsandaqueousmediaonthephasebehaviorandonthecompositionoftheinterfacialfilmandtheefficiencyforalkylpolyglucosidetomakeequalweightsofwaterandoiltoasinglephasewereinvestigated.Itwasfoundthattheoilmoleculeswithsmallmolecularvolumescanimprovethesolubilizingefficiencyofthesurfactanttoformsingle-phasemicroemulsion.Ininorganicsalt(NaCl)andacid(HCl)solutions,less1-butanolisneededthanthatinalkali(NaOH)solutiontoformmiddle-phasemicroemulsion.
简介:OnDecember12,2013theproject'Developmentandcommercialapplicationofcontinuousliquid-phasedieselhydrotreating(SLHT)technology'jointlyundertakenbyRIPP,SEI,theShijiazhuangRefiningandChemicalCo.(SRCC)andtheAnqingPetrochemicalCo.haspassedthetechnicalappraisalorganizedbytheScienceandTechnologyDivisionofSINOPECinBeijing.
简介:Anovelgas-phaseelectrocatalyticcellcontainingalow-temperatureprotonexchangemembrane(PEM)wasdevelopedtoelectrochemicallyconvertCO2intoorganiccompounds.TwodifferentCu-basedcathodecatalysts(CuandCu-C)werepreparedbyphysicalvapordepositionmethod(sputtering)andsubsequentlyemployedforthegas-phaseelectroreductionofCO2atdifferenttemperatures(70-90℃).ThepreparedelectrodesCuandCu-CwerecharacterizedbyX-raydiffraction(XRD),X-rayphotoemissionspectroscopy(XPS)andscanningelectronmicroscopy(SEM).Asrevealed,CuispartiallyoxidizedonthesurfaceofthesamplesandtheCuandCu-Ccathodiccatalystswerecomprisedofaporous,continuous,andhomogeneousfilmwithnanocrystallineCuwithagrainsizeof16and8nm,respectively.Theinfluenceoftheappliedcurrentandtemperatureontheelectro-catalyticactivityandselectivityofthesematerialswasinvestigated.Amongthetwoinvestigatedelectrodes,thepureCucatalystfilmshowedthehighestCO2specificelectrocatalyticreductionratesandhigherselectivitytomethanolformationcomparedtotheCu-Celectrode,whichwasattributedtothehigherparticlesizeoftheformerandlowerCuO/Curatio.Theobtainedresultsshowpotentialinterestforthepossibleuseofelectrical「enewableenergyforthetransformationofCO2intovaluableproductsusinglowmetalloadingCubasedelectrodes(0.5mgCucm2)preparedbysputtering.
简介:SixNi-MocatalystswithdifferentmetalcontentswerepreparedandcharacterizedbyN2adsorptionandX-raydiffractometry.TheactivephasemicrostructureofthesecatalystswasexaminedbytheRamanspectroscopy,temperatureprogrammedreduction(TPR),X-rayphotoelectronspectroscopy,andhigh-resolutiontransmissionelectronmicroscopy.Hydrodesulfurization(HDS)activityofcatalystsampleswereanalyzedinaflowfixed-bedmicroreactor.ThesulfidationdegreeofMoandthelengthoftheMoS2slabslightlyincreasedwiththeamountofmetalloadedfollowingsulfidation.Thissmallchangeisattributedtopolymolybdatespeciesobservedinalltheoxidizedcatalysts.Weakmetal-supportinteractions,asdeterminedbytheTPRtechnique,increasedtheNiSxsulfidationphaseandMoS2slabstacking.TheHDSactivityofthecatalystsamplesincreasedwiththenumberofactivesites.Forhighmetalloadingcatalysts,theirHDSactivitywasnearlyidenticalbecausethesulfuratomscannoteasilyapproachactivesites.ThischangeiscausedbythelargenumberofstackedlayersintheMoS2slabsaswellasthedecreaseinthespecificsurfaceareaandporevolumeofthecatalystsampleswithanincreasingmetalloading.
简介:Basedonthetensoranalysisofwater-sedimenttwo-phaseflow,thebasicmodelequationsforclearwaterflowandsediment-ladenflowarededucedinthegeneralcurvecoordinatesfornaturalwatervariable-densityturbulentflow.Fur-thermore,correspondingboundaryconditionsarealsopresentedinconnectionwiththecompositionandmovementofnon-uniformbedmaterial.Thetheoreticalresultsareappliedtothecalculationofthefloatopencaissonintheconstructionperiodandgoodresultsareobtained.
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简介:Thesegregationanddiffusionofboronduringheattreatmentswerestudied.Theinfluenceofboroncontents,agingtimeandappliedstressonFeMo2B2formationwasalsostudied.Finally,theeffectsofboroncontentsandFeMo2B2formationonthehightemperaturestrengthwerestudied.Boronatomsweresegregatedtoprioraustenitegrainboundaryduringnormalizingtreatment.Andtheseboronatomswereslowlydiffusedintothegraininteriorduringtemperingandagingat700℃.TheFeMo2B2phasewasonlyformedafter1,000hagingat700℃inalloycontaining196ppmboron.TheformationofFeMo2B2phaseisacceleratedbytheappliedstress.ItwasexpectedthattheformationofFeMo2B2iscloselyrelatedtotheredistributionofboronatoms.Thetensilestrengthsat700℃areincreasedwiththeincreaseofboroncontents.However,theformationofFeMo2B2phaseresultsinlowertensilestrength.
简介:Microstructuresandmechanicalpropertiesoftransientliquidphase(TLP)bondedmagnesiummetalmatrixcomposite(MMC)jointsusingcopperinterlayerhavebeeninvestigated.Withanincreaseofbondingtimesfrom5minto50minatbondingtemperatureof510℃,theaverageconcentrationofcopperinthebondedzonedecreased,themicrostructureinthezonechangedfromCu,α-MgandCuMg2toα-Mg,CuMg2andTiC,andmechanicalpropertiesofthejointincreased.Theshearstrengthofthejointbondedat510℃for50minreached64MPaduetothemetallurgicalbondingofthejointandimprovingitshomogeneityofcompositionandmicrostructure.ItisfavorabletoincreasethebondingtimeforimprovingmechanicalpropertiesofTLPbondedmagnesiumMMCjoint.
简介:Pr2Fe14B-La2Fe14B系统被衍射(XRD),微分扫描热量测定(DSC)和扫描电子显微镜学(SEM)与精力装备了的X光检查粉末调查散X光检查光谱学(版本)。水晶结构参数被完整侧面的Rietveld精炼决定。结果揭示了那所有合金(Pr1-xLax)2Fe14B使Nd2Fe14有空格组P42/mnm的B类型结构并且形成了连续固体在x=0.0之间的解决方案并且1.0。格子参数一,c,单位房间体积V和c/a比率与La集中线性地增加了。由thermogravimetry分析决定了,居里温度(TC),阶段转变温度和融化的温度(Pr1-xLax)2Fe14B在La内容之上线性地减少了。基于DSC大小和X光检查粉末衍射考试的结果,Pr2Fe14B-La2Fe14B系统被建立。
简介:FenanowirearraywithstrongshapeanisotropywasemployedasthesoftphaseinNd-Fe-Bbasednanocomposites.TheeffectsoftheFenanowiredistributiononmagneticpropertiesofthenanocompositeswereinvestigatedbymicromagneticsimulation.TheresultsindicatethattheshapeanisotropyofFewiresaddedinthesamedirectionastheuniaxialmagnetocrystallineanisotropyofthehardphasecannotincreasethecoercivityofthenanocomposite.Whenthenanowiresaredistributedperpendiculartotheeasyaxisofthehardphase,theshapeanisotropyofsoftphasecanretardthemomentsfromrotatingtothefullreverseddirection,leadingtoenhancedcoercivity.Inaddition,withincreasingthenanowirediameter,thecoercivityofthenanocompositedecreases,butthedipolarinteractionshowsdifferentrolesinmagneticreversalofnanocompositefordifferentdistributionsofnanowires.ThecurrentresultssuggestthatthecoercivityoftheNd2Fe14B/α-Fenanocompositecanbeenhancedbyintroducingthesoftmagneticnanowirearraywiththediameterlessthantheexchangelengthandwiththelongaxisalongthedirectionotherthantheeasyaxisofhardphase.