简介：采用一步法合成了氨基化四氧化三铁（NH2-Fe3O4）磁性纳米材料,并以XRD,IR等手段对其进行了表征.将NH2-Fe3O4组装到磁性玻碳电极表面,得了NH2-Fe3O4修饰的磁玻碳电极,并以该修饰电极为工作电极,研究了其电化学性能.利用差分脉冲溶出伏安法研究了铅（Ⅱ）离子和铜（Ⅱ）离子在该修饰电极上的电化学行为.结果表明：NH2-Fe3O4纳米粒子可显著提高Pb2＋和Cu2＋在电极表面的富集量,提高溶出峰电流.由于差分脉冲溶出伏安曲线中Pb2＋和Cu2＋的溶出峰电位差较大,且没有相互干扰,所以该电极可用于Pb2＋和Cu2＋的同时测定.
简介：Lid-drivenmixedconvectionhasbeengivenimmenseimportanceduetoitswiderangeofapplications.AT-shapedcavityisintroducedandpertinentparameterscontrollingmixedconvectionphenomenonareanalyzedinthispaper.Water-Al2O3nanofluidisconsideredinsidethecavitytoaugmentheattransferrate.Galerkinweightedresidualmethodoffiniteelementanalysisisappliedforthenumericalsimulations.Numericalsolutionisobtainedfordifferentsolidvolumefractionsofnanofluid(?=0-0.15),Grashofnumbers(Gr=0.1?5000)andReynoldsnumbers(Re=0.31?1000)inlaminarflowregime.Specialattentionisgivenontheanalysisofflowatthepuremixedconvectionregime.ItisfoundthatGrashof,ReynoldsandRichardsonnumbersalongwithsolidvolumefractionofnanofluidhavesignificanteffectonheattransfercharacteristicsinsidethecavity.ResultsarepresentedusingstreamlineandisothermcontoursalongwithrelatedvariationofaverageNusseltnumbersoftheheatedwallandaveragefluidtemperatureinsidethecavity.
简介：采用固相法制备La2O3与Sb2O3掺杂的钛酸锶钡陶瓷，研究其介电性能及相变特性。通过X射线衍射法分析体系微观结构并利用扫描电镜观察其表面微观形貌。（La,Sb）共掺杂的钛酸锶钡陶瓷具有典型的钙钛矿结构，且随着Sb2O3掺杂量的增多其平均粒径显著减小。La3＋离子以及Sb3＋离子均占据钙钛矿晶格的A位。La2O3与Sb2O3添加量的改变显著影响钛酸锶钡基陶瓷的介电常数以及介电损耗。La2O3改性的钛酸锶钡陶瓷其四方-立方相变为二级相变，且居里温度随着La2O3掺杂量的增多向低温方向移动。（La,Sb）共掺杂的钛酸锶钡陶瓷则体现为弥散相变，随着Sb2O3含量的增大而偏离居里－外斯定律越显著。由于Sb3＋离子对晶格原位离子的取代使得（La,Sb）共掺杂的钛酸锶钡陶瓷的介电常数最大值下的温度亦随着Sb2O3含量的增大而降低。
简介：ThecapacitytocaptureCO2wasdeterminedinseveralstoichiometriccompositionsintheLi2O–Bi2O3system.Thecompounds（Li7BiO6,Li5BiO5,Li3BiO4andLiBiO2phases）weresynthesizedviasolid-statereactionandcharacterizedbyX-raydiffraction,scanningelectronmicroscopyandN2adsorptiontechniques.Thesampleswereheat-treatedattemperaturesfrom40to750°CundertheCO2atmospheretoevaluatethecarbonateformation,whichisindicativeofthecapacityofCO2capture.Moreover,Li7BiO6showsanexcellentCO2capturecapacityof7.1mmol/g,whichisconsiderablyhigherthanthoseofotherpreviouslyreportedceramics.Li7BiO6isabletoreactwithCO2from240°Ctoapproximately660°CshowingahighkineticreactionevenatCO2partialpressurevaluesaslowas0.05.
简介：纳米Fe3O4作为一种功能材料,在生物医药、生物靶向材料、微波吸收材料和高梯度磁分离器等方面应用前景广阔,其潜在的生物毒性也备受关注。为研究纳米Fe3O4对生物体可能造成的氧化损伤,以昆明小鼠为受试体,设置5、10、20和40mg·kg-14个染毒组,腹腔注射染毒7d后,测定小鼠肺组织中活性氧（reactiveoxygenspecies,ROS）、还原型谷胱甘肽（glutathione,GSH）和丙二醛（malondialdehyde,MDA）的含量。结果显示,随着纳米Fe3O4染毒剂量的升高,肺组织ROS和MDA含量逐渐上升,GSH含量逐渐降低,各指标均呈一定的剂量-效应关系。剂量≥10mg·kg-1,肺组织ROS含量与对照组相比有显著差异（p〈0.05）;剂量≥20mg·kg-1,肺组织MDA含量与对照组相比有显著差异（p〈0.05）;剂量≥40mg·kg-1,肺组织GSH含量与对照组相比有显著差异（p〈0.05）。研究表明,较高剂量（≥20mg·kg-1）的纳米Fe3O4颗粒材料会引起小鼠肺细胞的氧化损伤。
简介：TiO2@ZrO2@Y2O3:有coremultishell结构的Eu3+合成粒子通过layer-by-layer(LBL)的联合被综合自己组装方法和一个solgel过程。获得的样品与扫描电子被描绘显微镜学(SEM)，传播电子显微镜学(TEM)，X光检查光电子光谱学(XPS)，X光检查衍射(XRD)，和荧光spectrophotometry。结果证明合成粒子有coremultishell结构，球形的形态学，和狭窄的尺寸分布。TiO2核心上的ZrO2层的存在能有效地阻止在TiO2核心和Y2O3壳之间的反应；为在在TiO2@ZrO2@Y2O3的TiO2核心和Y2O3壳之间的反应的温度:Eucoremultishell黄磷能被300提高
简介：Thecopper(Ⅱ）complex[Cu3(nta)2(azpy)2(H2O2)]·6H2O(nta=nitrilotriacetate,azpy=4,4′-azobispyridine)hasbeensynthesizedandcharacterized.TheX-rayanalysisrevealsthattherearetwokindsofcopper(Ⅱ）coordinationenvironments.Cu(1)hasadistortedsquareplanesymmetryandCu(2)hasadistortedoctahedralsymmetry.Cu(1)islinkedtoCu(2)throughntaandboundtoCu(1C)byazpy,andCu(2)islinkedtoCu(2A)throughazpy,whichextendstotwo-dimensionalnetworkwithlargerhombus1.2nm×1.7nm.
简介：TherearemanyprocessestoproduceCr2O3fromchrome-ores,DifferentparticlesizerangesofCr2O3powder,finepinmentgradegreenCr2O3andcoarsemetallurgygradeblackCr2O3,aremadebydifferentprocessesinChina,GreenCr2O3assuperfineandadditionandmetallurgygradeblackCr2O3usedtosynthesizeCr2O3graincanbeappliedtorefractories.ItisverydifficultforhighpurityCr2O3tosintertodensificationandTiO2additioniscontributedtodensificationofCr2O3sinteredathightemperature,Cr2O3grainswithrelativedensityof91%-95%aregainedbysinteringCr2O3withTiO2additionandelectrofusingCr2O3rawmaterials.
简介：Nitridatedβ-Ga_2O_3(100)substratewasinvestigatedasthesubstrateforGaNepitaxialgrowth.Theeffectsofnitridationtemperatureandsurfaceroughnessofβ-Ga_2O_3wafersontheformationofGaNwerestudied.Itwasfoundthatthemostoptimizednitridationtemperaturewas900°C,andhexagonalGaNwithpreferredorientationwasproducedonthewell-polishedwafer.Thenitridationmechanismwasalsodiscussed.
简介：TheNd2O3nanoparticleswhichmodifiedbyAOTwaspreparedusingmicrioemulsionmethodinthesystemofwater/xylene.L3edgeXAFSwasusedtodeterminethedifferenceofthelocalstructurearundNd^3+ionandtheelectricalstructurebetweenthenanocystallineNd2O3andthecoarsebulkmicrocrystallineNd2O3.ItwasfoundthatNd-Odistanceincreasedwiththeformofnanocrystalliteandtheintensityofabsorptionedgealsoenhancedatthesametime.
简介：Uniformlysizedα-Fe2O3hexagonalplateletsweresynthesizedbyahydrothermalprocessusingFe(OH)3suspensionandlargeamountofNaOH.ThereactionproductswerecharacterizedbyX-raydiffraction(XRD),scanningelectronmicroscopy(SEM),transmissionelectronmicroscopy(TEM),selectedareaelectrondiffraction(SAED),andavibratingsamplemagnetometer(VSM).Theresultsshowthatthehexagonalplateletsarefine,monodisperseandconsistingofsingle-crystals.Themagnetichysteresis(M-H)curveofthesamplesmeasuredatroomtemperatureindicatesthattheα-Fe2O3micro-plateletsexhibitferromagneticbehaviorswithrelativelylowcoercivity.
简介：Inthisletter,Fe2O3UFP（UltrafineParticles）hydrosolandorganosolwithhighthirdorderopticalnonlinearsusceptibility（3）havebeenreportedforthefirsttime.ThesurfacialmodificationofFe2O3UFPwithdodecylbenzenesulfonateions（DBS）canenhancethenonlinearopticalresponsethroughinterfacialconfinementofelectronmotion.Theinvolvedmechanismisdiscussed.
简介：TheRamanspectraof3%(molefraction)Y2O3-ZrO2(3Y)areobtainedatdifferenttemperaturefrom77Kto853K.Theresultsshowthat260cm-1Egand460cm-1Egmodesonthespectrashifttowardlowerwavenumberwiththeincreaseoftemperature;meanwhile,thecontinuityoftheHalfWidthatHalfMaximum(HWHM)andwavenumber(frequency)ofRamanbandsarebrokenandt-phaseonlypartiallytransformstom-phaseat523K.Basedontheexperimentalresults,thispaperdiscussesthet-phaselatticevibrationof3YandpresentstheimagesofvibrationdisplacementofsixRaman-activemodesfort-phaseofZrO2.TheanalysisindicatesthattherearediversitiesexistinginthedisplacementoftheatomicvibrationofRaman-activemodesbecauseoftheirdifferentsymmetriesatvarioustemperature,whichleadstothedifferentchangetendenciesofRamanbands.Furthermore,theabruptchangesofsomeRaman-activemodesindicatingtheatomicdisplacementareassumedtobethecondensationsofphononmodesinthet→mphasetransition.
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