简介：WeldingresearchofA6N01S-T5aluminumalloyprofileforhigh-speedtrainwasdonebyusinglaser-MIGhybridweldingandMIGweldingindividually.Andtheweldappearance,weldingdistortion,mechanicalpropertiesofthejointsandmicrostructureswereanalyzed.Thetestresultsdemonstratedthathigh-efficientweldingfortheprofilecanbeachievedbyusinglaser-MIGhybridwelding,thespeedofwhichcanbeover3.0m/min.Theprocessinghadagoodgapbridgingability，evenifthegapofthebuttjointwasupto2.0mm,agoodweldappearancecanalsobegot.Whilethehybridweldingspeedwasgreaterthan2.5m/min,theweldingdistortionofthelaser-tandemMIGhybridjointswasjustabout33%ofthatoftheMIGjoints,buttheweldingefficiencywasover3timesofMIGwelding.Andtensilestrengthofthehybridjointswas85%ofthatofA6N01S-T5basemetal,9%higherthanthatoftheMIGjoints.Fatiguepropertieswastestedindividuallywithpulsedtensilefatiguemethodintheconditionof1×107lifetime.Thetestresultsdemonstratedthatthefatiguestrengthofthejointswasalittlelowerthanthatofbasematerial,whichcouldbeupto115MPa.Butthefatiguestrengthofhybridweldingjointswas107.5MPa,whichwas23%higherthan87MPaofMIGweldingjoints.

简介：介绍一种金属/合金的生产方法,用于恒电流和恒电位条件下由混合硫化物(Cu2S,NiS)生产Cu-Ni合金,称为直接电化学还原(DER)。研究槽电压和槽电流等工艺参数对还原得到的化合物组成的影响,以生产工业所需的CuNi10,CuNi20和CuNi30等合金。在1200°C下采用循环伏安法(CV)考察Cu2S和NiS在CaCl2熔体中的电化学行为。根据CV研究结果,Cu2S的阴极还原是一步完成的,即Cu2S?Cu;NiS的阴极还原则分两步进行,即NiS?Ni3S2?Ni。恒电流研究表明,在10A电流下电解15min,可制备出最高硫含量为320×10-6的高纯CuNi10合金。扫描电子显微镜以及能量色散X射线能谱和光学发射光谱(OES)测试结果表明,在2.5V电压下直接电化学还原15min,可制备出杂质含量低(即硫含量小于60×10-6)的所选成分的Cu-Ni合金。

简介：Soil,cropandresidents'hairoverXiaoqinlinggoldminingregion,China,whichwasselectedasacasestudy,weresampledandanalyzedforHg,Cd,Pb,Cu,Cr,AsandZnconcentrations.Theconcentrationsofheavymetalsinsoilorcropandhairsampleswereusedtoassesstheirpotentialecologicalrisks,ortofindtheresponsestothesemetalsasevidencestoprovethepotentialriskwascomingdowntoobservedharm,respectively.Theresultsshowedthat,thesemetalsinsoilwererankedbyseverityofecologicalriskasHg>Cd>Pb>Cu>Cr>As>Zn,basedontheirsingle-elementindexes.Intheviewofthepotentialecologicalriskindexes,ofallsoilsamples,abouthalfhadsignificantlyhighorhighpotentialecologicalrisk,whichcoveredmorethan74%ofthestudiedregion.Mostoftheriskswere97.41%fromHg,PbandCd,especially,84.37%fromHg.Boththesingle-elementandpotentialecologicalriskindexesindicatedthat,theecologicalriskgradeshadaspecialspatialcharacteristic,andincreasedfromnorthwesttosoutheastgenerally.Thiswasagreedwiththespatialdistributionofthestrengthingoldminingactivitiesoverthestudiedregion.TheconcentrationsofHgandPbwerehigherthantheirrelativebackgroundsinthecorps,andwereeven9.48and25.09timeshigherthantheirrelativebackgroundsinresidents'hair,respectively.Alltheseshowedthattheheavymetalsinthesoilhadahighpotentialecologicalrisk,especially,hadbeenaffectingthesecrops'growingandyield,andeventheresidents'healththroughfoodstrains.Obviously,thesemetals'potentialecologicalharmhadbeencomingdowntoobservedharmtotheecology.

简介：对ＨＬＤ－ＦＱＺ－２Ｃ型程控式汽车发电机进行了工况分析和失效分析，同时对其关键易失效部件转子轴进行了受力分析，运用有限元模拟的方法对汽车发电机转子轴进行了应力分析，根据其材料特性Ｓ－Ｎ曲线，得到该型号汽车发电机的疲劳寿命极限，以及一般汽车发电机基于Ｓ－Ｎ疲劳曲线的寿命估计模型，并对再制造汽车发电机产品进行了可靠性预测。

简介：2006年1月6日。TopSolid首次新闻发布会在上海威斯汀大酒店钻石会议厅隆重召开。来自全国20多家企业、机构和媒体共70多人参加了此次会议。

简介：ThesusceptibilityofweldedjointfortheX65pipelinesteeltoH2Sstresscorrosioncracking(SCC)isinvestigated.SCCtestsonthesteelarecarriedoutintheenvironmentbasedonNACETM-01-77solutionwithsaturatedgaseousH2S.Thethresholdstressintensityfactorandcrackpropagationvelocityarecalculatedaccordingtowedge-openingloading(WOL)specimens.Thethree-dimensionalelastic-plasticfiniteelementanalysisofWOLspecimensisperformedbyusingtheFEMprogrammingpackageANSYS.Stressfieldandconcentrationofhydrogendistributionpropertyaheadofthecracktipareobtained.ThispapersurveyedthemicrostructureofweldedjointandstudiedonthemechanicalpropertiesofX65pipelinesteel.Itprovidesexperimentalbasisforstudyingstresscorrosion.Theresultsofnumericalanalysisareconsistentwithconclusionsofstresscorrosiontest.

简介：EA8S是三菱电机新研发的一款放电火花机，主要适用智能性手机、一般用途塑皎模、自动化、接插件、骨位和浇口、硬质合金模板等行业的模具加工。市场定位为普及经济型，在满足精度要求的前提下，最大程度提高加工效率。尤其在大面积加工、石墨电极加工的情况下，加工速度有显著提高。EA8S设备的主要性能有以下特点：

简介：本文以"2015年电子设计创新展会"为视角,对全球微波/射频(RF)用基材产品、技术与市场发展现况,作了报道与综述。

简介：备受全球内燃机行业瞩目的EngineChina2015经过一年的精心筹备,于2015年11月2~4日在北京国家会议中心隆重举办。本届展会是在国际、国内经济形势日益复杂、中国制造转型升级以及＂十二五＂规划收官和＂十三五＂规划启动的时间节点举办的,是相关政府部门和行业专业人士商讨行业发展形势和方向的最重要年度盛会,凸显了历史悠久的EngineChina内燃机展在行业的风向标作用。

简介：Inthiswork,asimpleandfacileone-potoleylaminesolvothermalsyntheticmethodwasdevelopedtosynthesizeCu_2ZnSnS_4(CZTS)nanocrystals.AndtheCu_2ZnSn(S,Se)_4(CZTSSe)thinfilmswerepreparedbyselenizingCZTSnanocrystals.TheobtainedCZTSnanocrystalsandCZTSSefilmswerestudiedusingX-raydiffraction(XRD),transmissionelectronmicroscopy(TEM),scanningelectronmicroscopy(SEM),energy-dispersiveX-rayspectroscopy(EDX),andultraviolet–visiblespectrophotometer(UV–Vis).TEMresultsshowthatthesphere–likeCZTSnanoparticleswithdiameterbetween12and35nmarepolydispersed.XRDstudiesindicatethatthepreparedCZTSnanocrystalsformkesteritecrystalstructure,andtheCZTSSefilmswithkesteritecrystalstructurearealsoobtainedattheannealingtemperaturesof500and550°C.Inparticularafterannealingat500°Cfor20min,theCZTSSefilmexhibitsasmooth,uniform,crack-free,andlarge-grainedtopographyandpossessesCu-poorandSn-richcomposition.Moreover,itshowsstrongopticalabsorptionfromvisibletonear-infrared(IR)region,anditsopticalbandgap(Eg)isfoundtobeabout1.44eV.

简介：2009年5月10日，由陕西省科学技术厅组织，咸阳市科技局主持，在陕西生益科技有限公司召开了对该公司研制的“S2600E复合基覆铜箔层压板”的科技成果鉴定会。与会专家听取了技术研究报告等相关汇报，进行了资料审查、现场考察、质疑答辩，经充分讨论后鉴定委员会同意该项目通过科技成果鉴定。