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500 个结果
  • 简介:尝试用六次甲基四胺和铜试剂联合分离法分离出锰等干扰离子,解决了传统分析法对部分高锰试样中的钙镁分析不准确的问题。

  • 标签: 高锰 EDTA 铜试剂 六次甲基四胺
  • 简介:文章介绍了用水泥净浆压蒸检验方法检测MgO安定性存在的有关问题.通过相应的对比试验和工程实际运用,对采用胶砂试件代替水泥净浆试件进行MgO水泥压蒸试验的合理性进行了分析和探讨.

  • 标签: 微膨胀混凝土 MGO 压蒸 安定性
  • 简介:摘要:2019年度在400㎡烧结机开展入炉料中MgO含量结构生产优化探索研究,随着内容的逐步深入,烧结过程趋于合理,通过对烧结矿MgO含量研究,发现其与烧结机流量与利用系数组成之间的关系,通过优化烧结机生产参数控制,对炼铁厂整体经济技术指标的提升有着巨大的促进意义,降低了铁前生产成本。

  • 标签: 入炉料 MgO含量 烧结矿
  • 简介:BycarbothermalreductionofMgOwithblackcarbonasreductionagentatahightemperature,MgOwasdepositedonthesurfaceofMgO-CaOclinker(ascoating)toimprovetheclinker'shydrationresistance.Inthepaper,effectofdepositiontemperatureandholdingtimeonthehydrationresistanceofthetreatedMgO-CaO,thedepositionmechanismandMgOcoatingkineticswereinvestigatedwithhydrationresistancetest,X-raydiffractometry(XRD)andscanningelectronicmicroscope(SEM).ResultsshowedMgOcoatinggrewina2DmodeonthesurfaceofMgO-CaOparticles;theMgOcoatingimprovedthehydrationresistanceofthecoatedMgO-CaOclinker,andthecoatedclinkerwouldbecomestrongerwhencoatedathigherdepositiontemperatureandlongerholdingtime.ThemeasurementsalsofoundthatMgOdepositionprocessvariedwiththedepositiontemperature:itwasmainlyachemical-controlledprocessattemperaturesbetween1400-1500℃,withanapparentactivationenergy(AAE)of97.8kJ·mol~(-1);itwouldchangeintoadiffusion-controlledprocesswhenthetemperaturerisingto1500-1600℃,withapparentactivationenergyof19.2kJ·mol~(-1).

  • 标签: 抗水化性能 沉积温度 涂层生长 镁钙砂 MGO 扫描电子显微镜
  • 简介:Thedependenceofperpendicularmagneticanisotropy(PMA)onthebarrierlayerMgOthicknessinMgO/CoFeB/Tamultilayersisinvestigated.TheresultsshowthatthestrongestPMAoccursinasmallwindowofabout2-4nmwiththeincreaseofMgOthicknessfroml-10nm.ThecrystallinedegreeofMgOandthechangeofinteratomicdistancealongtheout-of-planedirectionmaybethemainreasonsforthechangeofPMAinthesemultilayers.Moreover,theroughnessesof2-and4-nm-thickMgOsamplesare3.163and1.8nm,respectively,andboththesamplesshowPMA.TheseresultscouldbeusedtotunethemagneticcharacteristicoftheultrathinCoFeBfilmforfutureapplicationsinperpendicularmagneticdevices.

  • 标签: MGO 厚度 粗糙度 垂直磁 各向异性 氧化镁/型CoFeB
  • 简介:文章采用电感耦合等离子原子发射光谱法测定滑石中MgO含量。将试样经硫酸、氢氟酸溶解,盐酸浸取,定容摇匀,用电感耦合等离子体原子发射光谱法直接测定,方法回收率在99.8%~100.3%之间,测定的RSD(n=6)在0.31%~1.86%之间。该方法简化了样品处理步骤,提高了工作效率,分析成本降低,适合批量样品分析。

  • 标签: 电感耦合等离子体原子发射光谱法 滑石 氧化镁
  • 简介:ThefracturetoughnessofMgOpartiallystabilizedzirconia(MgO-PSZ)hasbeenmea-suredbythehardnessindentationmethod.TheinfluencesofheattreatmentonthefracturetoughnessK1cofMgO-PSZwerestudied,ItwasfoundthatthefracturetoughnessofMgO-PSZcanbegreatlychangedbydifferentheattreatmentprofile.Thefracturetoughnesswasimprovedbytheheattreatmentat1100℃afteragingat1400℃,TherewasthegreatestK1cvalue(11.30MPa.m^1/2)ofthesamplesagedat1400℃for2hfollowedbyasubse-quentannealat1100℃for10h.ThechangesinthemicrostructureofMgO-PSZceramicsagedwithdifferentthermaltreatmentwerestudieddbyuseoftransmissionelectronmicroscopy.

  • 标签: 氧化镁 MGO PSZ 微观结构 韧化处理 部分稳定氧化锆
  • 简介:以聚乙烯醇(PVA)作为络合剂与醋酸镁反应制得前驱体,采用静电纺丝法制得聚乙烯醇(PVA)/醋酸镁复合纤维,经焙烧后得到分布均匀、具有较高比表面积和多孔结构的MgO纳米纤维.对所制得的纳米纤维的结晶度、纯度和表面形貌,分别采用X射线粉末衍射、差热-热重分析(TG-DTA)、红外光谱(IR)、扫描电镜(SEM)等分析测试手段进行了表征.结果表明,煅烧温度对纳米纤维的结晶度和形貌有很大影响.

  • 标签: 氧化镁 纳米纤维 静电纺丝法 制备 煅烧温度 结晶度
  • 简介:ToxicityofMgOandZnOnanoparticlesatconcentrationsof250,500or1000mg/LforCitrusmaximaseedlingswasinvestigatedtoevaluatethepotentialityoftheiruseasnano-fertilizers.UptakeandtranslocationofmetaloxidenanoparticlesandlipidperoxidationweremeasuredandcomparedwiththoseofplantsexposedtothehighestequivalentconcentrationsofMg2+andZn2+.MgOnanoparticlesweretranslocatedfromrootstoshoots,whiletranslocationofZnOnanoparticleswaslow.ExposuretoMg2+andMgOatallconcentrationsentailedseveretoxicityandstrongoxidativestress.ZnOnanoparticlesshowedonlymildtoxicity,whileZn2+causedleafveinchlorosisandstrongoxidativestresstoplantshoots.Inconclusion,thetoxicityofMgOnanoparticlestotheplantresultedfromthedissolvedMg2+concentration,whilethatofZnOnanoparticleswasnotcorrelatedwiththedissolvedZn2+concentration.OurfindingsaresignificantfordevelopmentandapplicationofMgOandZnOnanoparticlesasnano-fertilizersinagriculture.

  • 标签: MGO and ZnO NANOPARTICLES CITRUS MAXIMA
  • 简介:Sinteredmagnesiaclinker(alsocalledsinteredMgO)waspreparedwithMg(OH)2(preparedbylightcalcininghydrationofmagnesite)andmagnesiteasstartingmaterials,respectively,bythetechnicalprocess:lightcalcining(850℃1h)→grinding→molding→firing(1600℃3h).ThemorphologyandstructureoflightcalcinedMgOpowderspreparedwithmagnesiteorMg(OH)2wereanalyzedbyXRD,SEMandFT-IR.ThesinterabilityandmicrostructureofsinteredmagnesiapreparedwithmagnesiteorMg(OH)2wereresearched.Theresultsshowedthat:(1)lightcalcinedMgOpowderspreparedwithmagnesiteorMg(OH)2werebothface-centeredcubicstructure.ThelightcalcinedMgOpreparedwithmagnesitehadtheresidualoffunctionalgroupCO32-,andthatpreparedwithMg(OH)2didn'thaveCO32-,andwaseasytobreak,whichreducedthegrindingtime.(2)BecauseofthehighactivityofthelightcalcinedMgOpreparedwithMg(OH)2andthecatalysisofthewaterresidualinthedecomposingprocessofMg(OH)2,theapparentporosityofsinteredmagnesiadecreasedto0.6%from2.0%ofbeforehydration,closedporositydecreasedto2.8%from6.1%,andbulkdensityincreasedto3.46g·cm-3from3.29g·cm-3.

  • 标签: 氧化镁 烧结 菱镁矿 SRD SEM
  • 简介:MgO-ZrO2unfiredbrickswithZrO2contentupto8%attheintervalof2%wereprepared,usingfusedmagnesia(MgO:97%)andfusedMgO-ZrO2clinker(ZrO2:14.33%)asstartingmaterialsandphenolicresinasbinder.TheeffectsofZrO2contentonthermalshockresistance(TSR)andotherpropertiessuchascoldandhotmodulusofrupturehavebeeninvestigated.Residualcoldmodulusofruptureratioafterheatingat1000℃andquenchingbyairblowingwasadoptedtocharacterizeTSR.AdditionoftheMgO-ZrO2clinkerimprovesTSR,attributingtothemicrocracktougheningeffectbythermalexpansionmismatchbetweendifferentphases.WhenZrO2contentgoesabove4%,theimprovingeffecttendstobemoderate.TheintroductionofMgO-ZrO2clinkercanalsoimprovetheHMORat1500℃,whiletheincreasedZrO2contentreducesCMORofthebricksprefiredat1600℃,duetothethermalexpansionmismatcheffect.Compromisingtheoverallproperties,theoptimalZrO2contentforsuchmagnesiabasedunfiredbrickissuggestedtobe4%.

  • 标签: 氧化镁 氧化锆 防火砖 抗热震性
  • 简介:摘要随着现代水泥行业的快速发展,对水泥生产各工序质量也提出更高的要求。然而现行水泥熟料煅烧过程中,其中存在的碱和MgO会带来明显的影响。本文分析了碱和MgO对熟料性能的影响。

  • 标签: MgO 熟料性能 影响
  • 简介:采用溶胶-凝胶工艺制备了MgO薄膜.X射线衍射谱显示,随热处理温度升高,薄膜结晶质量提高;原子力显微镜观测也得到相同的结果,且随热处理温度升高,薄膜表面粗糙度增加.

  • 标签: 溶胶-凝胶 MgO薄膜 结构 形貌
  • 简介:SlagcorrosionresistanceofMgOZrO2refractorieswasinvestigatedinthiswork.Theresultsindicatethatinanon-orientedelectricsteelslagsystemwithahighratioofcalciatosilica,theslagresistanceofMgOZrO2refractoriescanbedescribedasfollows:ZrO2reactswithCaOformingcalciumzirconatecompoundwhichstrengthensthematerialandblocksthechanneloftheslaginfiltration;however,inanorientedelectricsteelslagsystemwithahighconcentrationofsilicaandthelowratioofcalciatosilica,theslagcorrosionresistanceofMgOZrO2refractoriesisdifferent;ZrO2reactswithCaOformingthecalciumzirconateandsimultaneouslyonemoreproductC2Saswell;C2Scanimprovecorrosionresistancebyblindingporeandenhancingslagviscosity;therefore,itisexpectedtobethemajorreasonfortheenhancedcorrosionresistanceobservedforMgOZrO2refractories.

  • 标签: 耐腐蚀性能 耐火材料 氧化锆 氧化镁 二氧化硅 炉渣粘度
  • 简介:ThepaperdescribestheeffectofadditivesAl,Si,SiCandB4ContheexpansionofMgO-ZrO2-Cmaterialafterbeingcoked.TheresultsindicatethatAlandSicannotincreaseitshotandcoldstrength.AlandSiwereoxidizedtoformAl2O3andSiO2respectively,andthenreactedwithCaZrO3orstabilizerinc-ZrO2toformcalciumaluminate,spinel(MA),dicalciumsilicate(C2S)andforsterite(M2S).Meanwhile,α-C2Swastransformedtoγ-C2Sandc-ZrO2tom-ZrO2whentemperaturechanged.AlltheabovereactionsresultedinthedecreaseoftheamountofAl4C3andSiCandtheincreaseinbulkvolume,whichcausedthestructureofMgO-ZrO2-Cmaterialdestroyed.Hence,contrarytotheMgO-Cmaterial,whenaddingAl.andSi,theMgO-ZrO2-Cmaterialwouldbestructurallydeterioratedafterheat-treatmentanditsstrengthandcorrosionresistancedecreased.

  • 标签: 性质 氧化镁 MGO 二氧化锆 ZRO2