简介:Processmodelsareveryusefultocontrolhighefficientindustrialmetallurgicalprocesses.Howevertheiraccuracydependsstronglyonthechoiceofboundaryconditionsandthermodynamicaswellaskineticdataused.WhereasthecommercialdatabaseFactSageorThermocalcisusedasthesourceofthermodynamicdatathekineticparameterarecharacteristicforeachprocessandprocessdesign.Thereforeitisessentialtoestimatethekineticparameterinwelldesignedexperimentssupportedbyusingofnumericalmethods.Inthispaperthesteelmeltflowparameter,gas-meltinterfacialareaandmasstransfercoefficientobtainedin30tindustrialgasstirredladlesaredescribed.Ontheexampleofnitrogenabsorptionanddesorptionthepredictiveprocessmodelfornitrogencontrolwhileladletreatmentanddecarburisationprocessispresentedfordifferentsteelalloys.Themodellingresultsarecomparedwithresultsfromindustrialprocesses.
简介:TheoverallreactionwasdeterminedonthebasisofthedissociationconstantofTBAandtheratiooftheligandtotherareearthioninthecomplex.Theratelaw,rateconstantsandacitivitionenergiesforthereactionofLa3+,Gd3+andHo3+withTBAwerestudied.ItisshowninthestudythatprerequisitesforperformingdifferentialrateanalysisforbinaryrareearthswithTBAarethatthepseudo-first-orderparallelreactionmechanismshouldbeconformedwith,nomultinuclearcomplexwouldbeformedandtheco-colorationeffectscouldbeneglected.
简介:Theformationofsolidsolutioncombinedwithtricalciumphosphateanddicalciumsilicatecouldpromoteaconsiderableremovalofphosphorusfromliquidslagtosolidduringhotmetaldephosphorization,andthusthedephosphorizationbyusingmultiphasefluxescouldsignificantlydecreasetheconsumptionoflime.However,thereactionmechanismofmultiphasefluxeshasnotbeenunderstoodclearly.Inthepresentstudy,thephasediagramfortheCaO-SiO2-FeO-P2O5systemhasbeenmeasuredwithcertainoxygenpartialpressureathotmetalpretreatmenttemperature.ComparingwiththeCaO-SiO2-FeOsystem,shrinkageofliquidphaseareaathigherFeOcontentswasobservedat1673Kwithoxygenpartialpressureof9.2×10-11atm.
简介:Whitebody-color(Y,Gd)BxV1-xO4-x:Eu3+phosphorswerepreparedbycoprecipitationreaction.UnderVUVexcitationat147nm,theredemissioncolorimetricpurityof(Y,Gd)BxV1-xO4-x:Eu3+phosphorismuchbetterthanthatofcommercialPDP(plasmadisplaypanels)phosphor(Y,Gd)BO3:Eu3+.Butitsrelativeemissionintensityisonlyabout90%ofthecommercialphosphor.
简介:我们在甲烷(POM)的部分氧化上调查了填满的格子氧的锻烧温度,反应温度,和不同数量的效果到把perovskite类型LaFeO3氧化物用作氧施主而不是气体的氧的合成气体,它被大音阶的第五音胶化方法准备,并且氧化物被XRD,TG/DTA,和赌注描绘。结果显示粒子尺寸增加了,锻烧温度增加,当赌注和CH4变换衰退了,锻烧温度当气体的氧不在时作为氧施主用LaFeO3氧化物增加时。在象上面那样的高水平仍然是的公司选择92%,并且当锻烧温度增加了,稍微增加了。到甲烷空气的LaFeO3氧化物的暴露提高了氧迁居在有由于格子氧和氧化说的Fe离子的减小的损失联机的时间的体积同时。高反应温度对从向为有高公司选择的合成气体生产的表面的体积的氧种类的迁居有利。为由顺序的氧化还原作用反应的POM的产品分发和进化被填满的格子氧的数量与气体的氧决定。最佳的过程应该衰退甲烷的全部的氧化,和增加甲烷的部分氧化的选择。
简介:稀罕做地球的铜锰混合了氧化物催化剂被一起沉淀并且用铜硫酸盐,锰硫酸盐,和稀土元素的氧化物REO的机械混合准备(REO显示La2O3,CeO2,Y2O3,或Pr6O11)作为原料。样品被X光检查描绘衍射(XRD),规划温度的减小(TPR),氧化表面(s-TPR)的规划温度的减小,和规划温度的解吸附作用(TPD)。催化活动为水气体移动反应被测试。做稀土元素氧化物没改变原来的铜锰的水晶结构混合了氧化物,但是改变了interplanar间距,吸附表演和反应性能。与La2O3提高了这项活动,因为高铜分发和好减小,Cu-Mn的稳定性混合了氧化物。与CeO2和Y2O3也减少了到不同的度的样品的减小温度当在表面上改进Cu的分散时,这样,催化活动比undopedCu-Mn的好样品。Pr6O11-doped样品是困难的减少,表面铜的分散被降低,导致穷人活动。
简介:一系列Ni-CeO2催化剂被一起沉淀方法与Na2CO3准备,NaOH,并且混合急躁(Na2CO3:NaOH;1:1比率)同样急躁分别地。催化表演上的precipitants的效果,Ni-CeO2催化剂的物理、化学的性质在X光检查的帮助下被调查衍射(XRD),Brumauer-Emmett-Teller方法(赌注),Fourier变换红外线的光谱学(英尺红外),thermogravimetry(TG),和H2-TPR描述。Ni-CeO2催化剂为反向的水气体移动反应关于他们的催化表演被检验,并且他们的催化活动是被评价:Ni-CeO2-CP(Na2CO3:NaOH=1:1)>Ni-CeO2-CP(Na2CO3)>Ni-CeO2-CP(NaOH)。相关到特征结果,催化剂由一起沉淀准备了与,这被发现混合急躁(Na2CO3:NaOH;1:1比率)同样急躁氧空缺的大多数数量与高度驱散的Ni粒子伴随了,它做了相应Ni-CeO2-CP(Na2CO3:NaOH=1:1)催化剂展览最高催化的活动。当时Na2CO3或NaOH急躁在Ni-CeO2催化剂导致了更少或没有氧空缺。作为结果,Ni-CeO2-CP(Na2CO3)和Ni-CeO2-CP(NaOH),催化剂介绍了差的催化性能。
简介:RE-dopedNi-basedcatalystswerepreparedbysol-gelmethod.ThesecatalystswereappliedtothereactionofCO2reformingCH4tosyngas.ThestudiesrevealthatRE-doped(RE=La,Ce,Sm,Yb)Ni-basedcatalystsshowhighercatalyticactivitythanundopedNi-basedcatalyst,andwiththeincreasingofRE-dopedquantity,thecatalyticactivityofcatalystsexhibitsregularchanges.WhenRE-dopedquantityis0.2%(molarratio),thecatalystsshowthebestcatalyticactivity.