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简介：纳米大小的钇铝石榴石(钇铝柘榴石)粉末被与铵氢碳酸盐把一起沉淀方法用作综合一急躁。当碘在分别地，在答案的Y3+和Al3+的起始的集中在0.018和0.03mol/L被设置的条件和pH=8上在一起沉淀过程被介绍时，结果显示一位极其松开的钇铝柘榴石先锋被获得。因而，在在为2h的1173K的锻烧与30nm和更好的sinterability的一种平均谷物尺寸由monodispersed粒子组成以后，产生钇铝柘榴石搽粉。现在的结果显示修改一起沉淀方法，与是的碘添加剂，比常规一起沉淀方法优异，综合极其细小的钇铝柘榴石粉末。

简介：SphericalYAG:Ce3+phosphorparticleswithnarrowsizedistributionwerepreparedbyspraypyrolysis.Theeffectsoftheconcentrationofsolution,theflowrateofcarriergasandtheannealingtemperatureonthephosphormorphologywerestudied.Theproductivityofprecursorparticlesshowsatrendofdropafterrisingwiththeincreaseofconcentration.Raisingtheflowrateofnitrogencanimprovetheproductivityoftheprecursorparticles.Phosphorpreparedbyspraypyrolysishasobviouslyhigheremissionintensitythanthatsynthesizedbysolidstatereaction,spraypyrolysismakesCe3+ionswelldistributedinthecrystallatticeastheluminescentcenters,andphosphorparticleshaveregularsphericityandnarrowsizedistribution.

简介：以YAG（Y3Al5O12，钇铝石榴石，Al2O3和Y2O3的反应产物）为主要助烧剂的SiC／YAG复合陶瓷材料具有许多优良的性能，在诸多领域中存在巨大的应用潜力。综述了近年来SiC／YAG复合陶瓷材料的研究进展，并提出了目前研究工作中尚存在的一些问题，指出SiC／YAG复合陶瓷仍具有广阔的发展前景。

简介：ItwasagreatpleasuretobeinbeautifulFlorencewithover7,000geoscientstswhohadregistered.Iwasverymuchinvolvedintwosymposiaongeoethicsandgeoeducation.Theybothwentverywell,butitwasinterestingthatthegroupswhocameweresmall.Inourdiscussionapointofagreementwasthatwemustattackthegreatglobalproblemssuchasvastmalnutritionandthefactthatmostoftheworldpopulationhasproblemswithfoodandwaterresources,notgold!,

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简介：Inthispaper,MPt/C(M=La,Nd)catalystsofPEMFCweresynthesizedbymicrowaveradiationprocess.ThecrystallinityandstructureofcatalystswererespectivelyanalyzedbyXRDandnitrogenadsorptiontests.Theactivityofcatalystswasinvestigatedbyelectrochemistryexperiment.Theresultsshowedthat:1)comparedwithPt/Ccatalystpreparedbytypicalimpregnation-reductionprocess,thesizeofMPt/CcatalystparticledecreasedandtheavailablecrystalforO2reductionincreased;2)theMPt/CcatalystshadrelativelyhighBETsurfaceareas;and3)thesecrystaltransformationsoftheMPt/Ccatalystbroughthightheelectrocatalyticactivity,andasaresult,improvedthepowerofPEMFC.

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简介：Lanthanidehasattractedmuchattentioninthefieldofopticalcommunicationsinrecentyears.SomepropertyanalysesonopticalwaveguideofNd-dopedcrystalNdxY1-xAl3(BO3)4andNd:MgO:LiNbO3aremadeinthispaper,followedbyintroductionofthemethodsofexperimentationandtheoreticalcalculationfortheplanaropticalwaveguides.Therefractiveindexprofilesoftheopticalwaveguidesareanalyzed.Theaboveworkoffersusefulinformationforstudyonnewtypematerialsforopticalcommunications.

简介：PositronannihilationbehaviorshavebeenstudiedinthesinglephaseNd2Fe14BmagnetandthenanocompositeNd2Fe14B/α-Femagnet,preparedbymeltspinning.Theresultsshowedthatthenumberofvacancy-clusteratgrainboundariesincreaseswithincreasingannealingtemperatureforthebothtypesofmagnets.Theincreaseofthiskindofdefectcanimprovethecoercivityof

简介：Thehighrepetitionrate10J/10nsYb:YAGlasersystemanditskeytechniquesarereported.Theamplifiersinthissystemhaveamulti-passV-shapestructureandtheheatintheamplifiersisremovedbymeansoflaminarwaterflow.Inthemainamplifier,thelaserisfour-pass,andanapproximately8.5J/1Hz/10nsoutputisachievedintheprimarytest.Thefar-fieldoftheoutputbeamisapproximately10timesthediffractionlimit.Becauseofthehigherlevelsofamplifiedspontaneousemission(ASE)inthemainamplifier,theoutputenergyislowerthanexpected.Attheendwediscusssomemeasuresthatcanimprovethepropertiesofthelasersystem.

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简介：ThesolidsolubilityofCe、La、SmandNdinFeorNiatvarioustemperaturewasdeterminedbymeansofadiffusion-couplemethodwiththeaidofanelectronprobemicroanalyzer.Twomethods,namelyareamethodandwholerangemethod,wereproposedfordataprocessinginthepresentpaper.Theprincipleandre-latedproblemsintheexperimentaldeterminationofthesolidsolubilityofrare-earthelementsinFeorNibyuseoftheabovementionedmethodswerealsodiscussed.

简介：TheanalysisofavailableNdisotopedatafromtheTanzaniaCratonplacesimportantconstraintsonthecrest-mantleseparationages,andeventsmarkingjuvenilecrustaladditionandcrustalrecycling.Ndmodelagesdatetheoldestcrustextractionto3.16GaintheTanzaniaCraton,althougharockrecordofsuchantiquityisyettobefoundthere.Themostsignificantperiodofjuvenilecrustaladditionaswellascrustalrecyclingis2.7-2.6Ga.TheNdisotopesofmariesamplesshowthatchemicalheterogeneityexistedinthemantlebeneaththeTanzaniaCraton,withsomesamplesoriginatingfromsignificantlydepletedmantle,andmostsamplesoriginatingfromthemixtureofprimitivemantleanddepletedmantle.TheNdisotopesectionrevealssignificantdifferencesinNdisotopesbetweenthenortheratonandcentralcraton;comparedtothenorthcraton,thecentralcratonyieldsaNdmodelagethatisapproximately100Maolder,anditsεNd(t)valuesaremorenegative,indicatingthatthetwopartsofthecratonhavedifferentmantlesourceregions.DifferenttypesofgranitoidsaredistributedintheTanzaniaCraton,suchashigh-Kandlow-Algranite,ealc-alkalinegranite,peraluminousgraniteandtransitionaltypesoftonalite-trondhjemite-granodiorites(TTGs).Mostofthegranitoidsformedlaterthanthemarierocksinsyn-collisionandpostcollisionevents.

简介：TheNd2O3nanoparticleswhichmodifiedbyAOTwaspreparedusingmicrioemulsionmethodinthesystemofwater/xylene.L3edgeXAFSwasusedtodeterminethedifferenceofthelocalstructurearundNd^3+ionandtheelectricalstructurebetweenthenanocystallineNd2O3andthecoarsebulkmicrocrystallineNd2O3.ItwasfoundthatNd-Odistanceincreasedwiththeformofnanocrystalliteandtheintensityofabsorptionedgealsoenhancedatthesametime.

简介：Sm-NdandRb-Srwhole-rockisochrondatingofthesamplesofcumulatedgabbro,diabaseandandesiticporphyritefromtheArmantaiophiolite,Xinjiang,yieldedtheagesof561±41(Ma(εNd(t)=6.1)and392±17Ma(87Sr/86Sr)i=0.7041],whichstandfortheagesofcreationandlatermetamorphismoftheophiolites,respectively,ThecreationenvironmentoftheArmantaiophiolitesseemstoaback-arcbasincausedbythesouthwardsubductionofthetheArmantaiophiloitesseemstoaback-arcbasincausedbythesouthwardsubductionofthepalaeo-AsiaOcean.

简介：Cr的Nanopowder:Cr的GGG和nanopowder，Nd:有从0.1at.%到1.5at.%的Cr3+的不同集中的GGG被大音阶的第五音胶化方法用醋酸和乙烯乙二醇综合。热gravimetric分析和微分扫描热量测定(TGA-DSC)，X光检查衍射(XRD)和光致发光光谱学被用来描绘粉末。当在1000点对待时，雏晶尺寸是大约58nm?????????????????猯灵?匠?猼'T资???猼灵?????????猯'T??猼灵????￣?????猯'T????猯灵??猼'T?????吗????????????????‵渠????????浮？？

简介：R454.299020918激光感应等离子体冲击波碎石=Laser-inducedshockwavelithotripsy[刊,中]/孙永道,赵卫,杨斌洲(中科院西安光机所.陕西,西安(710068))∥物理.—1998,27(5).—282-285对激光感应等离子体冲击波碎石技术的物理机理、发展现状及未来趋势做了综合性评述,并结合实验研究对激光碎石中存在的重要技术问题进行了探讨,提出了一些可能解决的方法。图3参7(李瑞琴)