简介:Ti6Al4Visawidelyappliedinmedicalimplantssuchasbone,joint,andteethduetoitsexcellentmechanicalproperties,corrosionresistance,plasticityandthebiocompatibilityofthesurfaceoxide.However,thenativesurfaceoxidefilmisquitethin(about5nm)andtechniquessuchasmicroarcoxidation,plasmasprayedhydroxyapatitaeandplasmaimmersionionimplantationareusedtosynthesizethickersurfacetitaniumoxide.
简介:TheCADSdemofacilityisaimedtobuildaprototypelinacforthelowenergypartofthecontinuouswave(CW)superconductingprotonlinacanddemonstratetechnologyinthissection[1].IntheCADSroadmap,therealizationof25MeV10mAbeamisakeypoint.Thus,basedonthe10MeVCADSInjectorIIatIMP,IMPandIHEPwillbothcontributeacryomoduletoreach25MeVatthesiteofIMP[2].Todumpthebeamfromthelinac,webuildanewhighenergybeamtransportlinewithbendingangleof90°,toavoidback-scatteringgammaandneutronbeamstodamagethelinac.Fig.1showsthelayoutofthe25MeVdemofacility.
简介:Inthiswork,SMAT(surfacemechanicalattritiontreatment)wasperformedonTi6Al4V.PlasmanitridingoftheSMATedsampleswasinvestigatedincomparisonwithcoarse-grainedsamples.Thesampleswerecharacterizedusingopticmicroscope,SEM,TEMandVickersmicrohardnesstester.TheresultsshowedthatasignificantlythickercompoundlayerwithhigherhardnesswasobtainedfortheSMATedsampleswhencomparedwithun-SMATedsamplesafternitriding.CorrosionresistanceofTi6Al4VinaRinger’ssolutionwasstudiedbyelectrochemicaltechniquesincludingopencircuitpotentialmeasurement,potentiodynamicpolarizationandEIS(electrochemicalimpedancespectroscopy).Overall,ourresultsidentifiedthebeneficialimpactsoftheduplexSMAT/nitridingtreatmentoncorrosionbehaviourofTi6Al4V.Weartestswerealsoperformedonaball-on-disctribometerwherethetreatedsampleswererubbedagainsta6mmdiameteraluminaballunderanormalloadof5NusingRinger’ssolutionaslubricantmedia.ThefrictioncoefficientoftheSMATedandnitridedsampleswasreducedcomparedtotheuntreatedsamples.WearratesdemonstratedthatSMATcombinedwithnitridingimprovedwearresistanceofTi6Al4Valloy.
简介:Inthispaper,asurfacepotentialbasedthresholdvoltagemodeloffully-depleted(FD)recessed-source/drain(Re-S/D)silicon-on-insulator(SOI)metal-oxidesemiconductorfield-effecttransistor(MOSFET)ispresentedwhileconsideringtheeffectsofhigh-kgate-dielectricmaterialinducedfringing-field.Thetwo-dimensional(2D)Poisson’sequationissolvedinachannelregioninordertoobtainthesurfacepotentialundertheassumptionoftheparabolicpotentialprofileinthetransversedirectionofthechannelwithappropriateboundaryconditions.Theaccuracyofthemodelisverifiedbycomparingthemodel’sresultswiththe2DsimulationresultsfromATLASoverawiderangeofchannellengthsandotherparameters,includingthedielectricconstantofgate-dielectricmaterial.
简介:研究了YBaCu3O6~7超导催化剂上CO2的加氢制醇反应。考察了温度、压力和空速等条件对催化剂反应性能的影响。反应的主要产物是甲醇、CO和少量甲醚。利用XPS、XRD和AFM等技术对催化剂的结构、铜的存在状态和反应活性位进行表征发现,在反应过程中,YBa2Cu3O6~7由orthombic相转变为tetragonal相。反应活性位可能是Cu(I)物种。反应后催化剂颗粒的分散程度明显提高