简介：ThepreparationoftwotypesofmolecularsievesAlPO4-11andMAPO-11isreported.Theparticlesizeofthelatterishundredsofmicrons,about10timeslargerthanthatoftheformer.TheXRD,IRandDTAspectrahavedemonstratedthatmagnesiumhasbeenintroducedintotheframeworkofAlPO4-11.ThesuccessfulpreparationoflargesinglecrystalofMAPO-11willopenupanewareaforthepreparationoflargemolecularsievescrystalsinthefuture.ThelargeMAPO-11crystalcompoundisapromisinghostforthehost-guestassemblyofcompositematerials.

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简介：利用直接法合成未见文献报道的K8[ZnMg（H2O）W11O39]·15H2O，通过ICP，IR和XRD等方法对其结构进行表征，结果表明所合成的配合物具有Keggin结构．采用化学热扩渗法对合成配合物进行稀土扩渗实验，经XPS测试表明，有微量的钆渗进配合物的体相，并与组成元素存在键合作用，导电性测试结果表明，扩渗后试样的导电率提高10^5倍，是一种优良的固体电解质，有望成为具有实用价值的功能材料．

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简介：用单辊甩带法制备了不含高生物毒性元素的Ti60Zr10Ta15Si15非晶薄带,并在高于其晶化开始温度的不同温度下对该非晶薄带进行了真空退火,研究了该非晶薄带在磷酸盐缓冲溶液（PBS）中的电化学腐蚀行为及热处理对其显微组织及其电化学行为的影响。结果表明,用单辊甩带法制备的Ti60Zr10Ta15Si15金属薄带为完全的非晶态结构,其玻璃转变温度和晶化开始温度分别为759K和833K,经过878K真空热处理后,薄带发生了部分晶化,在非晶的基底上析出了Ti相;经过938K热处理后,薄带发生了完全晶化,晶化相主要由Ti、Si3Ta5和SiZr以及TiSi组成。动电位极化测试表明,该非晶合金在PBS溶液中可表现出较为优异的耐蚀性能,部分晶化可进一步提高该合金的耐蚀性能,而完全晶化的合金抗腐蚀性能明显下降。

简介：有0.2–的直径的新宏观规模的SBA-15范围；0.5公里被sol–准备；胶化方法，tetrabutylorthosilicate(TBOS)在被用作硅来源和triblock共聚物和polyoxyethylene辛基酚醚(OP-10)(P123)被用作模板。结果球形的样品被XRD描绘，N2adsorption–；解吸附作用，TEM和SEM方法。结果证明SBA-15宏范围的内部结构有宏多孔的隧道(0.5μ；m)并且我酣睡的骨骼(4–；5nm)。有层次毛孔结构的这些SBA-15宏范围为Emodin分子表明高吸收能力。

简介：Atwo-dimensionalsteadyReynolds-averagedNavier–Stokes(RANS)equationwassolvedtoinvestigatetheeffectsofaGurneyflaponSFYT15thickairfoilaerodynamicperformance.Thisairfoilwasdesignedforflightvehicleoperatingat20kmaltitudewithfreestreamvelocityof25m/s.Thechordlength(C)is5mandtheReynoldsnumberbasedonchordlengthisRe=7.76×105.Gurneyflapswiththeheightsrangingfrom0.25%Cto3%Cwereinvestigated.Theshearstresstransport(SST)k-ωturbulencemodelwasusedtosimulatetheflowstructurearoundtheairfoil.ItisshowedthatGurneyflapcanenhancenotonlytheprestallliftbutalsolift-to-dragratioinacertainrangeofanglesofattack.Specially,atcruiseangleofattack(α=3°),Gurneyflapwith0.5%Cheightcanincreaselift-to-dragratioby2.7%,andliftcoefficientby12.9%,respectively.Furthermore,thesurfacepressuredistribution,streamlinesandtrailing-edgeflowstructurearoundtheairfoilareillustrated,whicharehelpfultounderstandthemechanismsofGurneyflaponairfoilaerodynamicperformance.Moreover,itisfoundthattheincreaseofairfoildragwithGurneyflapcanbeattributedtotheincreaseofpressuredragbetweenthewindwardandtheleewardsidesofGurneyflapitself.

简介：134Csabranchingpointins-processpathwhichisshowninFig.1.Thebranchingratioisdefinedasfβ=λβ/(λβ+λn).Itcouldbededucedfromtheabundanceof134Baand136Basince136Bagoesthroughbothdecayandneutroncaptureof134Cswhile134Baonlyexperiencesdecaychannel[1].Duetoboth134Baand134Baarepures-processnuclei,thisbranchingpointisagoodapproachtodeterminethes-processparameters.Withtemperaturedependentβ-decayrateof134Cs,thetemperatureofs-processcouldbededuced.

简介：InstitutionofModernPhysics(IMP)hasdesigned,fabricatedandinstalledthefirstSRFcavityelectropolishingsystemofChina.It’ssizedfor1.3GHzSRFcavities,andalsocanworksformultiplecellcavitieswithfurtherupgradeofstructure.

简介：《数学课程标准》要求学生所掌握的空间与图形内容如下：能够借助不同的方法探索几何对象的有关性质；能够使用不同的方式表达几何对象的大小、位置与特征；能够在头脑里构建几何对象，进行几何图形的分解与组合，能够对某些图形进行简单的变换；能够借助数学证明的方法确认数学命题的正确性。图形与证明是空间与图形的核心内容之一，课标要求学生掌握基本的图形基础知识与基本技能；了解证明的含义，掌握证明的方法，体会证明的过程；能把所学的公理、定理和基本事实正确运用到证明的过程中，在合情推理的基础上发展初步的演绎推理能力；初步通过观察、实验、归纳、类比、推测获得数学猜想，体验数学活动充满着探索性和创造性，感受证明的必要性、证明过程的严谨性及结论的稳定性，它贯穿在整个几何知识的学习及运用之中．

简介：Asanimportantmulti-functionalmaterialappliedinsurfaceacousticwavedevices,opticalcommunications,laserandoptoelectronicsduetoitsgoodphotoelectricandpiezoelectricproperties,lithiumtantalate(LiTaO3)hasdrawnextensiveinterests[1].NumerousphysicalpropertiesofLiTaO3,suchasacoustical,electronicstructures,opticalpropertiesandeffectivemass,thermodynamicproperties,havebeenreportedinseveralpapers.Pointdefectswillaffecttheelectronicstructurewhichshouldberesponsibleformanyphysicalproperties,especiallyopticalproperties.

简介：Fieldemissionoccurredinsuperconductingradio-frequency(SRF)cavitiesisthemajorobstacleoftheacceleratorsoperatingathighgradient,whichpartlycausedbytheinnersurfacecontamination,suchasthehydrocarbonsandtheabsorbedresidualgas.Theplasmaprocessingcanbeaneffectivemethodtosolvethefieldemissionissues.Thepropertiesoflowtemperatureglowdischarge,whichwasargonplasmawiththechemicallyreactiveoxygen,wereinvestigatedfortheSRFcavitiesusedforCADSproject.

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简介：HierarchicalZSM-11microsphereswithintercrystallinemesoporouspropertiesandrod-likecrystalsintergrowthmorphologyhavebeensynthesizedusingaspotoftetrabutylammoniumasasingletemplate.XRD,FTIR,SEM,TEMandN2adsorptionanalysisrevealedthateachindividualparticlewascomposedofnanosizedrodcrystalsinsertingeachotherandtheintercrystallinevoidsexistingamongrodsgaveasignificantmesoporesizedistribution.Steamtreatmentresultdemonstratedtheexcellenthydrothermalstabilityofsamples.Variouscrystallizationmodesincludingconstanttemperaturecrystallization(one-stagecrystallization)andtwo-stagetemperature-varyingcrystallizationwithdifferent1ststagedurationswereinvestigated.TheresultssuggestedthatthecrystallizationmodesweremainlyresponsiblefortheadjustableparticlesizeandtexturalpropertiesofsampleswhilethesmallamountoftetrabutylammoniumbromidewasmainlyusedtodirecttheformationofbothZSM-11frameworkanditsintergrowthmorphology.Furthermore,theperformanceofoptimalZSM-11asanactivecomponentforthecatalyticpyrolysisofheavyoilwasalsoinvestigated.Comparedwiththecommercialpyrolysiscatalyst,thehierarchicalZSM-11catalystexhibitedahighselectivitytodesiredproducts(LPG+gasoline+diesel),aswellasamuchlowerdrygasandcokeyield,plusahighselectivityandyieldoflightolefins(C=3C=4)andverypoorselectivitytobenzene.Therefore,fullyopenmicropore-mesoporeconnectivitywouldmakesuchhierarchicallyporousZSM-11zeolitesveryattractiveforapplicationsincleanpetrochemicalcatalysisfield.

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简介：6,9,11-Trihydroxy-6a,12a-dehydrorotenoid1(coccineoneB)wassynthesizedfrom2-hydroxybenzaldehyde2andphloroglucinol.

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