简介：Synthesis,structureandmagneticpropertiesofRudopedperovskitestructuredmanganiteLa0.5Sr0.5MnO3wereinvestigatedexperimentally.Ahydrothermalmethodwasusedforthepreparationofthesamples.Ahigh-temperatureannealingprocesswasalsoemployedtomakeacomparison.AslightlyenhancementoftheunitcellvolumewasobservedwiththeincreaseofRuconcentration.Scanningelectronmicroscopyshowsthatthematerialsaremadeupofcube-shapedparticleswithdimensionofseveralmicrometers.Importantly,itisfoundthatboththeCurietemperatureTCandsaturationmomentcanbereducedbyRudoping.ThevalueofcoercivefieldisnotaffectedbytheintroductionofRu.

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简介：包含1,3,4-oxadiazole单位的热地稳定的聚合物作为溶剂在pyridine与芳香/脂肪族的二度酸氯化物通过芳香/脂肪族的bis-tetrazole混合物的Huisgen反应被综合了。获得的聚合物甚至在象DMSO和DMF那样的极的aprotic溶剂不可溶解或稍微可溶。相对高的固有的粘性价值(0.611.33dL/g，在在25点的0.125%H2SO4????????????????????????倠？？

简介：用浸渍法制备了一系列镍基催化剂并以苯加氢反应及二硫化碳中毒为手段考查了ＭｏＯ３对Ｎｉ基催化剂的改性机制。结果表明，钼的加入能增加Ｎｉ催化剂的催化活性和抗二硫化碳毒性，原因是钼的加入增加了催化剂的活性中心数量和镍的分散度，改变了催化剂与反应物所形成中间体的活化焓及熵。根据过渡态理论，钼对Ｎｉ基催化剂的影响即有电子效应又有几何效应，但以电子效应为主。更多还原

简介：本文对JM-2/JM-3转动惯量仪进行了改进,减小了实验误差.

简介：AnapplicatiopnoftheopticalpyrometerisstudiedformeasuringmonochromaticemissivitiesofcementclinkerwithvariousFe2O3contnet.Theidsaofusing“brightnesstemperature”isintroducedintotheeimssivitymeasurement.Inthismethod,thereisnoneedformeasuringanactualtemperatureofsamplesurfaces,onlywithdeterminingbothbrightnesstemperaturesofasampleandablackbodycantherequiredemissivitybeevaluatedaccordingtoWien'sradiationlaw.Inpractice,thecementclinkerisregardedasagreybody,themonochromaticemissivityisapproximatelyequaltothetotalemissivity,soasingle-colouropticalpyrometerisappliedforthispurpose,Testmeasurementsarecarriedouton10kindsofcementclinkers,Experimentaldataaretreatedbytheleastsquaremethod.Asaresult,theemissivityvariationwithtemperatureatacertainFe2O3contentisquitewellrepresentedbyεn=a+bT.Furthermore,thisworkfirstreportedthattheeimissivitiesofcementclinkerchangeconsierablywithFe2O3contents.Inmultiplecementproductionthisconclusionisveryimportant.

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简介：WepresentseveralcomparisonsofGEANT4simulationswithtestbeamdataandGEANT3simulationsfordifferentliquidargon(LAr)calorimetersoftheATLASdetector,Allrelevantpartsofthetestbeamsetup(scintilators,multiwireproportionalchambers,cryostatetc.)aredescribedinGEANT4aswellasinGEANT3.MuonandelectrondataatdifferentenergieshavebeencomparedwithMonteCarloprediction.

简介：在亲水性Fe3O4磁流体中，以甲基丙烯酸（MAA）为单体，N，N’-亚甲基双丙烯酰胺（MBA）为交联剂，采用光化学方法在水溶液体系中首先合成磁性聚甲基丙烯酸（PMAA）微球，进而在60℃下PMAA与稀土元素Dy离子反应合成具有荧光特性的磁性微球（FMPMs）．运用振动样品磁强计（VSM），光子相关光谱仪，傅立叶变换红外光谱仪（FTIR）和热重-差热分析（TG-DTA）分别对微球的磁性能，平均水合粒径,化学组成和表面形貌进行了检测．结果表明，荧光磁性高分子微球有超顺磁性，呈很好的球形，表面含有丰富的稀土羧酸盐．

简介：通过对分子筛原粉添加黏结剂,制备出了适宜作为吸附材料的成型分子筛颗粒.随后对成型分子筛颗粒进行活性组分的负载,并采用氮气吸附等温线对不同样品的比表面积和孔径分布进行了分析表征.通过考察样品对氨气的动态吸附能力,对活性组分的种类和含量进行筛选和优化,最终确定以质量分数为8%的H_2SO_4作为分子筛基氨气吸附材料的配比组成.通过与活性炭吸附材料的对比发现,在低湿度和高湿度2种条件下,分子筛基防护材料对NH3的防护性能均优于活性炭.

简介：针对DC/DC的质子位移效应,选取具有抗TID能力的DC/DC器件作为试验样品,在3MeV质子辐照条件下获取了器件的失效位移损伤剂量.结果表明,DC/DC功能失效是PWM控制器输出异常导致的.通过等效^60Coγ辐照及退火试验,排除了TID效应的影响,确定器件功能失效是由位移损伤引起的.高温退火后器件功能恢复,并立即对该器件进行了测试.结果表明,输出电压、电压调整度、负载调整度、交叉调整度、纹波及负载跃变时的输出电压均大幅衰退.利用这些敏感参数,获取了位移损伤导致的电源性能衰退模式.根据位移损伤缺陷类型及退火温度,分析了DC/DC的退火规律,可为DC/DC质子辐射损伤模拟试验方法的建立及其空间应用提供依据.

简介：Thegreenlong-after-glowluminescencefromTb3+-dopedSr2SiO4phosphors,whicharesynthesizedbythehightemperaturesolidstatereactioninareductiveatmosphere,isobservedinthispaper.Theresultsshowthatunderultravioletexcitation,theobtainedphosphorsproduceanintensegreen-lighting-emissionfromtheTb3+,andthegreen-lightinglongafter-glowluminescencerelatedtoTb3+canlasthalfanhouraftertheirradiationsourcehasbeenremoved.Moreover,theeffectsofco-dopingLi+,Dy3+,Er3+,Gd3+,andYb3+withTb3+onthedecaypropertiesandthermoluminescencepropertiesareinvestigatedtoconfirmthelong-after-glowmechanism.

简介：Intheunderwater-shockenvironment,cavitationoccursnearthestructuralsurface.Thedynamicresponseoffluid-structureinteractionsisinfluencedseriouslybythecavitationeffects.Itisalsothedifficultyinthefieldofunderwaterexplosion.Withthetraditionalboundaryelementmethodandthefiniteelementmethod(FEM),itisdifficulttosolvethenonlinearproblemwithcavitationeffectssubjectedtotheunderwaterexplosion.Tosolvethisproblem,undertheconsiderationofthecavitationeffectsandfluidcompressibility,withfluidvisciditybeingneglected,a3Dnumericalmodeloftransientnonlinearfluid-structureinteractionsubjectedtotheunderwaterexplosionisbuilt.Thefluidspectralelementmethod(SEM)andtheFEMareadoptedtosolvethismodel.AftercomparisonwiththeFEM,itisshownthattheSEMismoreprecisethantheFEM,andtheSEMresultsareingoodcoincidencewithbenchmarkresultsandexperimentresults.Basedonthis,combinedwithABAQUS,thetransientfluid-structureinteractionmechanismofthe3Dsubmergedsphericalshellandshipstiffenedplatessubjectedtotheunderwaterexplosionisdiscussed,andthecavitationregionanditsinfluenceonthestructuraldynamicresponsesarepresented.Thepaperaimsatprovidingreferencesforrelevantresearchontransientfluid-structureinteractionofshipstructuressubjectedtotheunderwaterexplosion.

简介：Thebubblesriseupandburstatthefreesurfaceisacomplextwo-phaseprocess.AfreeenergylatticeBoltzmannmethod(LBM)modelisadoptedinthispapertostudythisphenomenon.Theinterfacecapturingtechnique[Zhengetal.,2006]isusedtodealwiththehighdensityratioproblem.TheLaplacelawandtheair-waterinterfacecapturingabilityarevalidatedforthemultiphasemodel.Theinteractionbetweenthesinglebubbleormultiplebubblesandthefreesurfacearestudiedbythemultiphasemodel.Theforceactingonthebubbleandtheevolutionofthefreesurfaceisstudied.Meanwhile,effectoftheinitialdistancebetweentwoadjacentbubblesoninteractioneffectsofmultiplebubblesisinvestigatedaswell.

简介：Inthisworkweconsidertheproblemofshapereconstructionfromanunorganizeddatasetwhichhasmanyimportantapplicationsinmedicalimaging,scientificcomputing,reverseengineeringandgeometricmodelling.ThereconstructedsurfaceisobtainedbycontinuouslydeforminganinitialsurfacefollowingthePartialDifferentialEquation(PDE)-baseddiffusionmodelderivedbyaminimalvolume-likevariationalformulation.Theevolutionisdrivenbothbythedistancefromthedatasetandbythecurvatureanalyticallycomputedbyit.Thedistancefunctioniscomputedbyimplicitlocalinterpolantsdefinedintermsofradialbasisfunctions.SpacediscretizationofthePDEmodelisobtainedbyfiniteco-volumeschemesandsemi-implicitapproachisusedintime/scale.Theuseofalevelsetmethodforthenumericalcomputationofthesurfacereconstructionallowsustohandlecomplexgeometryandevenchangingtopology,withouttheneedofuser-interaction.Numericalexamplesdemonstratetheabilityoftheproposedmethodtoproducehighqualityreconstructions.Moreover,weshowtheeffectivenessofthenewapproachtosolveholefillingproblemsandBooleanoperationsbetweendifferentdatasets.

简介：PlanarringresonatorwaveguidesarefabricatedinthinfilmsofAs2S3chalcogenideglass,depositedonsilicaon-siliconsubstrates.WaveguidecoresaredirectlywrittenbyscanningthefocusedilluminationofafemtosecondTi:sapphirelaseratacentralwavelengthof810nm,throughatwo-photonphoto-darkeningprocess.Alargephotoinducedindexchangeof0.3–0.4refractiveindexunitsisobtained.Theradiusoftheringresonatoris1.9mm,correspondingtoatransmissionfreespectralrangeof9.1GHz.Ahighloaded（intrinsic）Qvalueof110,000（180,000）isachieved.Thethermaldependenceoftheresonatortransferfunctionischaracterized.Theresultsprovidethefirstreport,tothebestofourknowledge,ofdirectlywrittenhigh-Qringresonatorsinchalcogenideglassfilms,anddemonstratethepotentialofthissimpletechniquetowardsthefabricationofplanarlightguidecircuitsinthesematerials.

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简介：有从30～80nm的尺寸的Fe3O4nanoparticles被湿milling铁粉末在一家行星的球工厂综合。阶段作文和同样综合的产品的形态学被X光检查衍射(XRD)测量，扫描电子显微镜学(SEM)和传播电子显微镜学(TEM)。NanosizedFe3O4粒子被湿milling准备金属性的铁粉末(?200网孔，99%)在与不锈钢装备的一家行星的球工厂，使用的小瓶与50:1并且以300rpm的旋转速度的ball-to-powder团比率在提取的水下面熨球。在这个方法的铁球的使用在Fe3O4formation起了一个关键作用。现在的技术简单，这个过程是容易的执行。

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