学科分类
/ 25
500 个结果
  • 简介:RapidsolidificationofCu-Pbmonotecticalloyshasbeenaccomplishedduringfreefallina3mdroptube.BothmacrosegregatedanduniformlydispersedstructuresareobservedinCu-40wtpctPballoydroplets,whereasdropletsofcompositionCu-64wtpctPbexhibitonlymacrosegregationmorphologies.Themicrostructuresarestronglydependentondropletsize.Thehigherundercoolingtendstofacilitateliquidphaseseparationandresultsinmoreextensivemacrosegregationinsmallerdroplets.ThereexistsapronouncedtendencyforthePb-richliquidtooccupythesurfaceofthedropletsofbothcompositions,resultingfromthequitelowersurfacetensionofthePb-richphaseandcausingaPb-richlayeratthesurfaceofthesolidifieddroplet.ThenucleationofmonotecticcellsintheCu-40wtpctPbdropletswithdispersedstructurespreferentiallyoccursatthedropletsurface.Asinglenucleationeventtakesplacemorefrequentlyasdropletsizeisreduced.

  • 标签: 铜铅合金 偏晶合金 显微组织 结晶 凝固
  • 简介:ThetreatmentoftheGacuncomplexCu-PbbulkconcentratewithhighZn,Ag,etc.,byoxygenpressureacidleachingwasstudied.Theprimarycopperandleadmineralsintheconcentratearetetrahedriteandgalena.Thetreatmentoftetrahedritewasrarelystudied,andmostofsilveroccurredinthemineraltoo.Theoptimumoperatingparametersofoxygenpressureacidleachingwereestablishedbyconditionaltests.Undertheseparameters,theresultofpilotscaletestshowedthattheleachingpercentagesofcopperandzincwereseparatelyashighas98.9wt.%and94.9wt.%,whileleadandsilverweretransformedintosulfateandsulfideprecipitations,respectively.Thecopperandzincinlixiviumwerereclaimedbyextraction-electrowinningandpurification-electrowinning,respectively,andtheleadandsilverintheresiduewerereclaimedseparatelybycarbonatetransformation-silicofluoricacidleachingandthiourealeaching.

  • 标签: 非铁的冶金学 合成回收 沥滤的氧压力酸 复杂 Cu-Pb 体积专注 黝铜矿
  • 简介:Al-4。5Cu-5Pb合金被扔的沙和寒冷准备。一样的合金也是在1.6MPa的一个煤气的压力扔的水花。微结构特征展览一对为沙和寒冷铸石金的好树枝状的形态学粗糙。Equiaxed谷物被观察因为水花形成了合金。穿测试采用一根大头针--在圆盘上类型安装,揭示更加更低与寒冷和沙铸石金的相比水花穿扔的合金。词法特征在显示的标本和碎片上穿轨道混合oxidative-cum-adhesive为在现在的调查测试的这些合金穿机制。(编辑作者摘要)36个裁判员。

  • 标签:
  • 简介:摘要;本设计采用电感耦合等离子发射光谱法(ICP—OES)对岩石样品中的CuPb,Zn,Mn,Ni进行了测定,样品用四酸()熔矿,不经分离杂质,即可直接测定。该方法选择CuPb,Zn,Mn,Ni的测定分析波长分别为324.7nm,220.3nm,202.5nm,257.6nm,221.6nm分析了用HCl提取与用王水提取,样品首先经磨样机碎至200目,用去离子水湿润后,用四酸熔矿,再将坩埚放置恒温电热板上加热,最后分别用王水或盐酸提取再定容,对其中的CuPb,Zn,Mn,Ni做探究实验。

  • 标签: ICP,岩石,铜铅锌锰镍
  • 简介:目的:探讨料姜石对水中CuPb的吸附效果。方法:研究了不同粒径、温度、时间、用量、金属离子浓度等条件下料姜石对水中CuPb吸附效果的影响。结果:料姜石对水中CuPb的吸附效果与粒径、温度、时间、用量基本正相关,随参数的增加,吸附率提高,达到一定量后变化趋势不明显;与金属离子浓度呈负相关,随金属离子浓度的变大,吸附率逐渐降低。结论:本研究对料姜石的物化性能进行了初步评价,结果表明,料姜石对水中部分重金属确实有良好的吸附效果,为制备天然、低成本的新型净水剂提供了新的参考

  • 标签: 料姜石 CU PB 吸附率
  • 简介:建立起HNO3-H2O2-HF体系微波消解前处理样品,利用电感耦合等离子体质谱(ICP—MS)同时测定土壤中的铬(Cr)、镍(Ni)、铜(Cu)、砷(As)、铊(Tl)、铅(Pb)6种重金属元素含量的方法。该方法的相关系数在0.9996~1.000,相对标准偏差在0.669%~3.02%,加标回收率为94.68%~115.5%,检出限为2.004~312.4ng/L,结果表明该方法满足重金属分析的要求。用建立起的方法测定了来自湖南、湖北、云南、贵州、河南、福建、辽宁7个省45个产区烟田土壤中的Cr、Ni、Cu、As、田和Pb6种重金属元素含量;与对应烟叶中的6种重金属含量相比,聚类分析结果表明不同省区间土壤中的重金属含量无明显差异,而烟叶中却差异明显。

  • 标签: 电感耦合等离子体质谱(ICP—MS) 土壤 重金属元素 微波消解
  • 简介:TheadsorptionkineticsofPb^2+ondifferentsoilsandmineralswithvariablechargeswasstudiedbythetwoion-selectiveelectrodetechniqueatdifferentpHandconcentrations.Theresultsshowedthatmorethan95%ofadsorptiononallthesamplesoccurredduringthefirst5minutes.Alladsorptiontime-dependentdatacouldfitthesurfacesecond-orderequationverywell.ThevaluesofXmweregoethite>kaolinite,andlatosol>redsoilatthesameinitialreactionconcentration.Thevaluesofkwerekaolinite>>goethite,andlatosol>redsoilatthesamereactionpHandinitialconcentration.ThehigherthesuspensionpH,thefastertheadsorptionoccurred.ThemeaningofXmgotbythetwoion-selectiveelectrodetechnique(onekindofbatchtechnique)wasdifferentfromthatbythemiscibledisplacementtechniqueinthattheformerwasonlytheequilibriumadsorptionamountatadefiniteconcentrationandpH,butthelatterwasalmostequaltotheadsorptioncapacityatadefinitepHwithmuchlessinfluenceofconcentration.OnePb^2+wassupposedtooccupytwoadsorptionsitesastheadsorptionmechanismisconcerned.

  • 标签: 土壤 表面电荷 离子吸附 吸附动力学 铅离子 铜离子
  • 简介:UltrasonicvelocitieshavebeenmeasuredinsinglephaseBi1.7Pb0.3Sr2CaCu2O8+xandBi1.7Pb0.3Sr2Ca2O10+xpolycrystallinesamples.Anomalouschangesofbothlongitudinalandtransversevelocitieswereobservednear200K,whichindicatesthatsomestructuralphasetransitiomightoccur.Theelasticconstantsofthesesampleshavebeendeterminedfromthemeasuredultrasonicvelocitydata,whicharemuchsmallerthanthoseofYBa2Cu3O7-yandBaTiO3,manifestingthattheinterlayercoup-lingwilldramaticallydecreasewhenthec-axesoftheunitcellsoftheseperovstite-likemultilayerceramicsincrease.ThevaluesofPoissonratio,however,ofthoseceramicsareveryclose,implyingsimilarinteratomicbondingforces.Correctedtovoid-freestate,theDebyetemperatureofthesematerialsisestirnatedas270±20k.ThetemperaturedependenceofDebyetemperaturesforthesematerialsisalsocalculatedbyusingthesamemethodandreportedforthefirsttime.

  • 标签: ceramic INTERLAYER multilayer longitudinal CONSTANTS Poisson
  • 简介:本文建立了微波消化-原子吸收光谱法测定中成药中CuPb、Hg、As的方法。四种元素方法的相对标准偏差RSD%为2-4.8%,回收率在90~110%之间,定量检出限分别为6.8μgCu/g(干态)、0.41μgPb/g(干态)、0.13μgAs/g(干态)、0.1μgHg/g(干态)。

  • 标签: 中成药 原子吸收光谱法 铜、铅、砷、汞测定
  • 简介:TheprocesstoobtainhighT(110K)phasequickly,themicrostructureandpropertiesofAg-sheathedBi(Pb)-Sr-Ca-Cu-Osuperconductortapeshavebeenstudied.ItwasfoundthattheformationtimeofthehighTcphasewasgreatlyshortenedbytheadditionofmoreCaandCutothenominalcompositionofBi(Pb):Sr:Ca:Cu=2:2:2:3andtheadoptionofappropriatesinteringtemperatureandcoolingrate.SuperconductorpowderwithpredominanthighT,phasewaspreparedaftera840C/50htreatment.TheJoftheAg-sheathedtapesandthemagneticfielddependenceofJwereobviouslyimprovedbyrepeatedlypres-singandsintering.Themaximumtransportcurrentdensityat77Kinazeromagneticfieldwas12,200A/cm2.ThemagneticdependenceofJwassummarizedasfollows:6.450A/cm2(B⊥1.B∥S.0.1T)1,810A/cm2(B⊥1.B∥S,1T),390A/cm2(B⊥1.B∥S,2T)(B:magneticfield.1:electriccurrent.S:surfaceoftapes).TheimprovementofJwasattributedtotheformationoftheplate-likestructurewithhomogeneouscompositiondistributionandthestrongc-axistexture.

  • 标签: SUPERCONDUCTOR Ag-sheathed tape High T_ephase Critical
  • 简介:用同步辐射光电子谱详细研究了Cu(111)面上超薄Pb膜随厚度与退火的反应。发现室温下Cu(111)面上亚单层Pb以二维密积岛的形式生长。退火至200℃形成Pb-Cu表面合金。这种表面合金只发生在Cu(111)面的最外的一个原子层。作为在单晶Cu(111)表面诱使薄膜层状生长的活化剂,Pb的表面合金化可能会对它的活化作用产生不利影响。

  • 标签: 光电子谱 表面合金化 表面亚单层铅膜 铅铜合金 层状生长
  • 简介:1主题内容与适用范围受中国微量元素科学研究会委托研究人发、血清的统一分析方法,经一年多专家教授努力工作现予以公布。血清中钙、镁、锌、铁、铜、锰、镉、铅、钴的测定方法。推荐该法,适用于血清中钙、镁、锌、铁、铜、锰、镉、铅、钴的测定。

  • 标签: 原子吸收测定法 血清 CA Mg ZN Fe
  • 简介:摘要在分析原子吸收法原理的基础上,本文对原子吸收法在矿石中Zn、Cu、及Pb元素检测中的实际应用问题展开了分析,发现采用该方法可以实现元素含量准确、高效检测。

  • 标签: 原子吸收法 矿石检测 金属元素
  • 简介:1主要内容与适用范围本文受中国微量元素科学研究会委托研究人发、血清的统一分析方法,经一年多专家教授努力工作现予以公布。人发中钙、镁、锌、铁、铜、锰、镉、铅、钴的测定方法。推荐该法,适用于人发中钙、镁、锌、铁、铜、锰、镉、铅、钴的测定。

  • 标签: 原子吸收测定法 人发 CA Mg ZN Fe
  • 简介:TheTruongSonFoldBelt,locatedatthenortheasternmarginoftheIndochinaBlock,isconsideredtobetectonicallylinkedtothesubductionofthePaleotethysOceanandsubsequentcollision.SeponisoneofthemostimportantsuperlargedepositsoftheTruongSonFoldBelt.OurLA-ICP-MSzirconU-PbdatingresultsshowthatgranodioriteporphyrysamplesfromtheSepondeposithaveagesof302.1-4-2.9Ma,whichisacrucialphaseformagmatic-tectonicalactivitiesfromtheLateCarboniferoustoEarlyPermianandhasavitalinfluenceonthemineralizationofcopperandgold.ZirconfromgranodioriteporphyryyieldsεHf(t)valuesof4.32to9.64,andTDM2hasanaverageageof914Ma,suggestingthatthesourceofthegranodioriteporphyryintheregionweremainlymantlecomponentsbutunderwentmixingandcontaminationofcrustmaterials.TheCe^4+/Ce^3+valueofzirconinthegranodioriteporphyryvarysgreatlyfrom2.4to1438.29,whichshowsmagmamixingmightoccur.Consideringthecharacteristicsoftraceelementsinthezirconandthewholerockgeochemicalcharacteristicsofintrusionrocksaswellasthecharacteristicsofregionalvolcanic-sedimentaryassociation,itisindicatedthatthetectonicsettingmaybethecontinentalarcenvironment.TheSeponAu-Cudepositisderivedfromemplacementofcalc-alkalineintermediate-acidmagmawithcomingfromdeepsourcesinthesubductionprocessofthePaleotethysOcean,formingporphyryMo-Cu,skamCu-Aumineralizationandahydrothermalsedimentary-hostedAumineralizationinthewallrocks.

  • 标签: Granodiorite PORPHYRY ZIRCON U-PB AGES Hf
  • 简介:

  • 标签:
  • 简介:用志不分,乃凝于神。你只须专注.奋斗着,猛勇地奋斗着.持续着,永远的持续着,胜利就是你的了。

  • 标签: 信念 意志 “专注” 心理学