简介:ANewmethod,namedatmosphericpressureplasmapolishing,fortheultra-smoothmachiningofthesiliconbasedmaterialsisintroduced.ByinputtingtheCF4gasintotheatmosphericpressureplasmaflame,highdensityreactiveradicalswillbegenerated,whichwillthenreactwiththesiliconbasedmaterials.ThereactionproductisthevaporizationoftheSiF4,whichcanbeeasilyprocessed.Inthisway,theatomicscalematerialremovalcanberealizedandthedefectfreeultra-smoothsurfacecanbeobtained.Anexperimentalsetupisbuiltup,andtheSiCpolishingexperimentiscarriedout.TheAFMtestresultshowsthatthefinishedsurfaceroughness(Ra)canbeimprovedfrom4.529nmto0.926nmin3minutes.
简介:Inthispaper,usingthethermo-decompositionquantitativemethodtodeterminethealitecontentincementclinkerhasbeenstudied.Itisshownthatthealitecontentdeterminedbythethermo-decompositionmethodisveryclosetothatobtainedbytheopticalmicroscopymethod.Thepracticalquantitativeanalysisofaliteincementclinkerwascarriedoutbythethermo-decompositionmethodandaquitesatisfactoryresulthasbeenobtained.
简介:阶段地水晶(陆军)模型被雇用与格子失配和一个小倾斜角度在飞机凸的底层上模仿取向附生的层的生长的过程。系统的免费精力,取向附生的层的全部的原子序数,和弯曲和底层的角度的效果的变化被分析。结果证明当底层的表面是飞机时,免费精力随底层倾斜角度的增加增加,并且也,取向附生的层的全部的原子序数增加;当底层的表面是凸的时,免费精力随底层角度并且那么也的增加减少取向附生的层减少的全部的原子序数。这是取向附生的层的表面的边疆与增加凸的底层的倾斜角度从步bunching改变到hill-and-valley方面结构的原因。这些结果在对另外的方法结果的好同意。
简介:关于mesomechanics的一个新方法有限元素的研究被建议预言山峰砍mesoscopic上的材料放大的mudded置闰的力量。基于几何、机械的参数,与样品获得的种类失败标准一起变丑特征,样品上的单轴的压缩测试通过一个有限元素的模型被模仿,它从单轴的压缩测试的实验室产出与数据一致的值,暗示方法是合理的。把模型基于这,一shear测试被执行计算山峰砍mudded置闰的力量,与在文学报导的价值一致,从而提供为调查mudded的机械性质的一条新途径置闰材料。
简介:
简介:Inthisstudy,highlyporousforsteritescaffoldswithinterconnectedporositiesweresynthesizedusingmulti-stepsintering(MSS)method.Thestartingpowderwasnanosizedforsterite,whichwassynthesizedfromtalcandmagnesiumcarbonatepowders.Thephasecomposition,averageparticlesizeandmorphologyoftheproducedforsteritepowderwerecharacterizedbyX-raydiffractiontechnique(XRD)andtransitionelectronmicroscopy(TEM).Forsteritescaffoldswereproducedbyfoamymethodusingpolymericsponges.MSSprocessincludingthreestepswasusedtoefficientlysintertheforsteritenanopowderswithoutdestroyingtheinitialporousstructureofpolymericsponges.TheresultsshowedthatMSStechniqueisanefficientandappropriateproceduretoproducehighlyporousforsteritescaffoldswithporesizeintherangeof100-300μm.Thecompressivestrength,compressivemodulusandporosityofC12specimen(sinteredat1650℃for1hwithsubsequentannealingat1000℃,for1000min)was1.88MPa,29.2MPa,and72.4%,respectively,whichisveryclosetothatofcancellousbone.Theapproachstudiedinthisresearchcanbedevelopedforothernanostructureceramicstoproducehighlyporousscaffoldswithinterconnectedporositiesforloadbearingapplications.
简介:Mn-Zn铁酸盐(Mn1−xZnxFe2有不同作文的O4)被象pH的如此的合成条件的一起沉淀方法,和影响准备价值,混合答案和NH4他们的微观结构和磁性上的HCO3答案被讨论。样品被X光检查衍射(XRD)和磁化测量仪器描绘。格子参数和综合材料的平均水晶的尺寸与相关软件Jade.5从相应XRD模式被计算。为不同pH价值的样品,当pH价值是7.0,8.0和9.0时,仅仅一个阶段被发现。有7.0的pH价值的样品展出了最高的浸透磁性的正式就职,最低强制力量,和使结晶的最好。为有7.0的pH价值的不同R价值的样品,仅仅一个阶段与R在所有样品,和样品被观察2.3的价值展出了最高的浸透磁性的正式就职和最低强制力量。作文主要有afected磁性的正式就职随Zn(x)的内容的增加增加,但是当x超过0.6时,减少的磁性,和浸透。强制力量的趋势相反是。然而,当x价值直到0.8时,没有磁力被展出。
简介:λ-MnO2waspreparedbycolumnmethodfromnormalspinelLiMn2O4withpurityof99.38%.TheinfluenceofLiMn2O4grainsizeandacidityofleachingsolutiononthelithiumleachingprocesswasstudied.TheresultsshowthattheappropriaterangeofLiMn2O4grainsizewas60-160meshesandtheconcentrationofleachingsolutionHClwas0.1mol·L-1.TheadsorptioncapacityQofλ-MnO2forlithiumincreasedwiththeincreaseofpHandchangedmarkedlyatpH6.0-10.0.Itwas3.80mmol/gatpH12.0.ThedistributioncoefficientsKdofLi+andNa+were3.406×104and2.300respectively,andtheseparationcoefftcientaLiNawas1.481×104atpH6.5.Asaresult,λ-MnO2isahighperformanceion-sievematerialforlithiumion.
简介:Adirectelectrolesscopper(Cu)coatingontungstenpowdersmethodrequiringnosurfacetreatmentorstabilizingagentandusingglyoxylicacid(C2H2O3)asareducingagentwasreported.TheeffectsofcoppersulfateconcentrationandthepHoftheplatingsolutiononthepropertiesofthepreparedW@Cucompositepowderswereassessed.ThecontentofCuinthecompositepowderswascontrolledbyadjustingtheconcentrationofcoppersulfateintheelectrolessplatingsolution.Auniform,dense,andconsistentCucoatingwasobtainedundertheestablishedoptimumconditions(flowrateofC2H2O3=5.01mL/min,solutionpH=12.25andreactiontemperature45.35℃)byusingcentralcompositedesignmethod.Inaddition,thecrystallineCucoatingwasevenlydispersedwithintheW@CucompositepowdersandCuelementinthecoatingexistedasCu0.TheformationmechanismfortheW@Cucompositepowdersbyelectrolessplatingintheabsenceofsurfacetreatmentandstabilizingagentwasalsoproposed.
简介:Samplesofacobalt-basedalloythatunderwentasurfacetreatmentwereevaluated.Thesamples,whichwereobtainedbycastingalloyASTMF75,weregroundandpolishedononesideuntilamirrorfinishwasobtained.Thesampleswereencapsulatedinwollastonite(W)usinguniaxialpressure,treatedat1220℃for1handsubsequentlytemperedinwater.Thecharacterisationofthesampleindicatedthatpartoftheceramicencapsulatingmaterialwasmechanicallyincorporatedonthemetallicsurfacebygrowthoftheoxidelayerofthealloy.Afterthermaltreatment,aseriesofspecimensweresubmergedinasolutionwith5-foldsimulatedbodyfluid(5SBF)for3,5and21days.Characterisationbyscanningelectronmicroscopy(SEM),energydispersivespectroscopy(EDS)andX-raydiffraction(XRD)indicatednucleationandgrowthofahomogenouslayerofapatite,beginningonthethirddaywhenthesamplewassubmerged.
简介:异构或合成的材料的有效热传导性为在科学和工程的特定的功能是材料选择和设计的一个必要物理参数。有效热传导性重重地在部分和每个阶段的空间分发上被依靠。在这个工作,基于图象的有限元素方法(女性)被用来与不同毛孔结构计算多孔的陶艺的有效热传导性。与象理论(EMT)方程和平行建模的有效媒介那样的以前的理论模型相比,基于图象的女性的罐头与相对稳定的偏差被用于材料系统的一个大变化。基于图象的女性的计算的偏差主要来自之间的差别二维(2D)想象并且三维(3D)真实系统的结构,和一个实验被执行证实这个假设。因素影响2D和3D有效热传导性被学习由对女性说明精确性和申请条件基于图象女性。