学科分类
/ 25
500 个结果
  • 简介:IntroductionIn2O3·Snfilmshavehightransparency(>95%)withinthevisiblespectralregion,lowresistivity(10-2—10-4ohm·cm)atroomtemperatureandsuperiorthermalstability.Thesefilmshavebeenappliedtosolarcells,electronicsandphotoelectronicsfields.Inrecentyears,organometallic-CVDmethodhasemergedasasuccessfulalternatetothephysicalmethodsandgeneralCVDforthegrowthofthesefilms.TheMO-CVDtech-

  • 标签: Metallorganic chemical VAPOUR DEPOSITION (MOCVD) Tin
  • 简介:Aquantumdynamiccalculationonafive-dimensionalO2/LiF(001)modelsystemisperformedusingthemulti-configurationtime-dependentHartreemethod.Theobtainedresultsshowthatthemechanismofrotationalanddiffractiveexcitationindetails:Comparisonwiththerotationalexcitedstate,theinitiallynon-rotationalstateisseentofavortheinelasticscatteringintherotationalexcitationprocess.Thesurfacecorrugationcandampthequantuminterferencesandproduceagreateramountofrotationalinelasticscatteringattheexpenseoftheelasticprocessintherotationalexcitationprocess.Thediffractionprocessandtheaverageenergytransferredintotherotationalanddiffractivemodearealsodiscussed.

  • 标签: 非弹性散射 旋转状态 衍射过程 表面波纹 氟化锂 氧气
  • 简介:美国宇航局在加州帕萨迪纳的喷气推进实验室研究成功了一种制造YBa2Cu3O7-α高温超导电缆(封装在金属套管内)的新方法。据称,这种方法成本较低,过程易于控制,且对各种前体材料有很强的适应能力。该分4个步骤:生产具有化学(配)比的前体(Precursor)粉;将前体粉包封在金属套管内;用轧制的方法使前体粉固结;在液态锂金属浴槽内进行处理,使之转变成超导组

  • 标签: 粉末冶金 金属套管 高温超导电缆 锂金属 实验室研究 喷气推进
  • 简介:Themicrostructureandslagerosionfractaldimensionofreactioninterfaceofβ-Sialon-Al2O3brickusedin300MtironladleofBaosteelhavebeenstudiedbySEMandXRD.Theresultsindicatedthatβ-Sialon-Al2O3brickexhibitedexcellentslagresistance.Themainwearmechanismofβ-Sialon-Al2O3brickismainlyfromthespallingcausedbythermalmechanicalstressandattackedbyslagsecondly.

  • 标签: 耐火材料 三氧化二铝 制备 β-硅铝氧氮聚合材料 石英砖 显微结构
  • 简介:Basedonthedifferenceofhydroxygroupconfigurationondifferentplanesofα-Fe2O3nanoparticles,usingthespecialadsorptionandcoordinationofphosphateonthe(001)planeofα-Fe2O3,well-crystallizedandwelldispersedα-Fe2O3nanodiskswithdiameterof150–200nmandthicknessof40–80nmweresynthesizedviaahydrothermalmethod.Themagneticpropertiesofsynthesizednanodiskswereinvestigated.Itwasfoundthatthenanodiskspossessedasaturationmagnetization(Ms)of0.38emu/g,aremanentmagnetization(Mr)of0.031emu/gandacoercivityof452.91Oeatroomtemperature.TheMrandcoercivityofsynthesizedα-Fe2O3nanodisksarehigherandtheMsislowerthanthoseofotherpreviouslyreportedα-Fe2O3nanostructures.

  • 标签: 纳米粒子 氧化铁 饱和磁化强度 制备 生长 封闭
  • 简介:

  • 标签:
  • 简介:Al2O3-MgOcastableshavebeenwidelyusedforworkingliningsofsteelladleduetotheirsuperiorhotstrengthandcorrosionresistance.Inthiswork,effectsofmicrosilica,ultrafinealuminaandMgOfinesadditionsontherheologicalbehaviorofthecastableswereinvestigatedbymeansofIBBrheometerV1.0tomeasuretorque(shearstress)undervaryingshearrates.Theresultsshowthatrheologicalpropertiesofcastablesatvaryingshearratesaresignificantlyimprovedwithincreaseofmicrosilicaadditions(from1mass%to5mass%)andcorrespondingdecreaseinwateraddition;thereisonlylittlechangeinrheologicalbehaviorwithvariationofultrafinealuminaandMgOfinesadditions.Optimumultrafinealuminaandmicrosilicaadditionsarerecommendedforcastableswithgoodrheologicalbehavior.

  • 标签: 超细氧化铝 流变行为 浇注料 氧化镁 水泥 剪切速率
  • 简介:BasedonthetechniqueforpreparingLaCl3viadirectpyrolysisofrareearthchloridesolution,ajetpyrolysisreactorwasdesignedandtheintra-reactortemperatureandchemicalreactionswerenumericallysimulatedusingcomputationalfluiddynamics(CFD)technique.Theresultsshowthattheflowratevariationatthefuelinletdoesnotlargelyaffectthetemperatureinthereactor,whiletheincreaseinexternalpressureatthematerialinletrapidlydecreasestheaveragetemperature,Venturitemperature,andoutlettemperature.TheCH4andO2insidethereactorarecombustedcompletely,andwhenthematerialinletpressureis\90Pa,theLaCl3isfullypyrogenated.ThecontentsofCO2,La2O3,andHClfluctuateneartheVenturitubeandfinallystabilize.La2O3contentattheoutletisinatop-to-bottomgradient.

  • 标签: Jet-flow PYROLYSIS Chemical REACTION NUMERICAL SIM
  • 简介:T2O模式(TVtoOnline/Offline),是将电视节目的内容传播到电子商务终端,进行即时消费;或者将电视节目内容带到线下产业链,进行即时体验。从互联网O2O概念中延伸出来的"T2O",已成为电视人践行互联网思维的一种新尝试。2014年5月,旅游卫视和淘宝网"阿里旅行·去啊"一起,第一次提出了"T2O"的概念,双方以《鲁豫的礼物》试水,共同探索旅游节目电商化的全新商业模式。

  • 标签: 淘宝网 旅游产品 内容传播 T2O 旅游卫视 东方卫视
  • 简介:目的:分析新生儿重度窒息常见治疗措施。方法:对2003年1月-2007年10月之间发生的20例新生儿重度窒息复苏的临床资料进行回顾性分析。结果:11例在5分钟内复苏,7例在10分钟内复苏,1例在20分钟内复苏,窒息复苏成功率在95%,死亡仅1例。结论:新生儿重度窒息应清理呼吸道,建立呼吸,保持呼吸道通畅。

  • 标签: 新生儿重度窒息 复苏
  • 简介:研究了MWCNT-H2O纳米流体的光学及光热特性,利用紫外-可见-近红外分光光度计结合积分球原理测试了不同质量分数的纳米流体在太阳能全波段(250nm<λ<2500nm)的透射率。利用太阳辐射对纳米流体的光热转换特性进行了测试。实验结果表明:纳米流体的透射率明显低于水的,并且纳米流体的透射率随着粒子质量分数的增加而降低。纳米流体(质量分数为0.02%)的最高温度比水提高了31.87%,集热量比水增加了54.14%。MWCNT-H2O纳米流体有望用在直接吸收式太阳能集热系统中。

  • 标签: 纳米流体 太阳能 光热特性 透射率
  • 简介:Thecorrosionbehaviorandanti-corrosionmechanismoftheZn-Ni-Al2O3compositecoatingwereinvestigatedbySEM,EDSandXPS.TheresultsindicatethatthecorrosiontypeoftheZn-Ni-Al2O3coatingsinneutral5wt.%NaClsolutionisuniformcorrosion.ThepresenceofcompactanduniformlydispersednanoaluminaparticlessubstantiallyinhibitsthecorrosionofZn-Ni-Al2O3compositecoatings.Intheinitialcorrosionstage,thecorrosiveproductsofZn-NimatrixformacompactZnCl2·4Zn(OH)2layer.Withthedevelopmentofcorrosion,somenanoaluminaparticlesareembeddedandformaNienrichmentlayer.InNienrichmentlayer,NipresentsasNiandNiO.

  • 标签:
  • 简介:TheinfluencesoffourkindsofadditivesaddedintothematrixofMgO-Al2O3unbunedproductswereinvestigated,TheresultsshowthatsampleswithproperMgO/Al2O3rationandproperadditionofCr2O3(2%-4%)havegoodthermalshockresistanceandslagcorrosionresistanceaswell,XRDandSEMdeterminationresultsindicatethatakindofcompoundspinel(Mg,Al,Cr)O4wasformedandthemicrostuctureofthesamplesaredenser.

  • 标签: 添加剂 性质 氧化镁 三氧化二铝 三氧化二钴 耐火材料
  • 简介:a small set of international English language proficiency tests such as TOEFL and IELTS is developing with great momentum. Test localization,and one cannot replace the other. Notwithstanding his strong arguments for localizing language tests Yang (2004) acknowledges that developing a test on the intercultural norm does not mean eradication of the native speaker norm or complete localization of the test,if one test is carried out to assess the English language proficiency of students from other countries

  • 标签:
  • 简介:Fe2O3和ZnO的粉末混合物是在一家高精力的行星的球工厂的milled综合ZnFe2O4和X光检查粉末diffractometry被用来获得阶段,雏晶尺寸和Fe2O3和ZnFe2O4的microstrain的相对内容。Fe2O3的格子常数被房间精炼方法获得。macrokinetics和事的结构进化被学习,结果证明ZnFe2O4的mechanochemical合成的动力学过程适合Avrami-Erofe'ev模型并且被成核生长机制,和结构的macrokinetics理论在燃烧合成研究控制区域能被用来也描述运动过程。

  • 标签: 结构宏观动力学 合成过程 铁酸锌 机械球磨 粉末衍射仪 行星球磨机
  • 简介:TheelectrooxidationofBilirubin(BR)inN,N’-dimethylformamide(DMF)andDMF+H2Omixedsolventisinvestigatedbyvoltammetrytechniques,insiturapidscanthinlayerspectroelectrochemistryandinsituESRspectroscopy.ThedatarevealthattheoxidationprocessofBRundergoesmanystages,whichareallspedupbytheintroductionofwater.ThespeciesofbilirubintakingpartinthereactionisfoundtobechangedfromBRinDMFintoBR’inthemixedsolventsandtheanodicpeakpotentialisshiftedcorrespondinglyfrom+0.58Vto+0.026-+0.35V(vs.Ag/AgCl,1.0MKCl).Freeradicalsandthedimerizationofthemareobservedduringtheoxidation.

  • 标签: ELECTROOXIDATION BILIRUBIN biliverdin.