简介：采用电场、磁场、应力场和温度场多场耦合成形与烧结一体化技术制备高致密Fe-2Cu-2Ni-1Mo-0.8C合金,利用光学显微镜和扫描电镜对该合金的显微组织以及磨损表面进行观察和分析,重点研究耦合外加脉冲磁场对合金耐磨性能的影响。结果表明,在电场、应力场和温度场三场耦合放电等离子烧结技术的基础上进一步耦合适合的脉冲磁场,可明显改善烧结合金微观组织和合金元素分布的均匀性,不仅提高合金的耐磨性,同时还可显著提高合金的耐磨性能均匀性。在峰值电流、基值电流、频率、占空比分别为2700A、360A、50Hz和50%的脉冲电流以及烧结压力为30MPa的条件下烧结铁基合金粉末3min,耦合外加脉冲磁场强度为2.36×106A/m时,烧结材料的耐磨性能最佳,合金的磨损机制主要为粘着磨损。
简介：基于国外定向凝固氧化物／氧化物共晶复合陶瓷的晶体生长动力学行为的研究成果，阐述其动力学机制，分析动力学因素对微观结构形态的影响，探讨晶体生长热力学、动力学行为与微观结构形态之间的关系，同时结合以燃烧合成、快速凝固技术制备的新型高强韧A12O3/ZrO2（Y2O3）共晶复合陶瓷，探讨共晶复合陶瓷在快速凝固条件下的晶体生长动力学行为。结合定向凝固与快速凝固两种晶体生长机制，得知过冷度、凝固界面前沿的温度梯度是影响晶体生长方式的重要因素，且受二者决定的凝固速率（即晶体生长速率）则决定材料的最终微观结构与形态。
简介：混合氧化物(Ce0.6Zr0.4O2)由帮助微波的加热一起沉淀准备了的CeO2-ZrO2被用作支持经由早期湿的受精的方法与各种各样的CuO内容(0wt.%15wt.%)准备一系列CuO/Ce0.6Zr0.4O2催化剂。获得的CuO/Ce0.6Zr0.4O2样品被N2吸附，XRD，拉曼，TEM和H2-TPR技术，和他们的催化活动描绘因为公司氧化被调查。结果证明CuO/Ce0.6Zr0.4O2催化剂的活动被CuO的内容强烈影响，并且有10wt.%CuO的催化剂在公司氧化展出了最好的催化活动，它能在催化剂被归因于CuO，和高氧空缺集中的高分散和reducibility。
简介：Eu2+andDy3+codoped(Ca,Sr)7(SiO3)6Cl2yellowphosphorsweresuccessfullysynthesizedbyself-fluxmethod.Thestructure,morphologyandphotoluminescencepropertieswereinvestigatedbyX-raydiffraction(XRD),scanningelectronmicroscopy(SEM)andphotoluminescencespectra.Theas-preparedphosphorshowedabroademissionspectrumcenteredat550nmforEu2+single-dopedphosphor,whilelocatedat548–544nmfortheEu2+,Dy3+codopedsamplesunderexcitationat380nmlight.TheemissionintensitywasgreatlyimprovedwhenDy3+wasdopedintothe(Ca,Sr)7(SiO3)6Cl2:Eu2+system.Thecomposition-optimizedsamplewith3mol.%ofDy3+andconstant10mol.%ofEu2+exhibiteda220%PLenhancementcomparedtothephosphorwith10mol.%Eu2+single-doped.Meanwhile,itwasfoundthatthequantumefficiencyofphosphornamely(Ca,Sr)7(SiO3)6Cl2:3mol.%Dy3+,10mol.%Eu2+couldgetupto24.6%.Thesynthesizedyellow-emitting(Ca,Sr)7(SiO3)6Cl2:Dy3+,Eu2+isapromisingcandidateashigh-efficiencyyellowphosphorforNUV-excitedwhiteLEDs.
简介：DirectextractionofmetalsfromsolidswithcomplexingagentsinsupercriticalCO2(SC-CO2)hasrecentlyattractedinterestsinseparation,purification,recovery,andanalysisofmetals.Inthepresentstudy,thestatic/dynamicextractionofrareearthelements(Nd,Ce)fromtheiroxides(Nd2O3,CeO2)withorganophosphoruscomplexeswithHNO3andH2OinSC-CO2wasinvestigated.ThestaticextractionefficiencyofNdfromNd2O3withthetri-n-butylphosphate(TBP)-HNO3complexcouldreach95%underoptimizedexperiment...
简介：Steelmakingisenergyandmaterialintensive.Thatiswhysteelisalwaysdemonizedandconfrontedwithincriminationsandrequirementsforreductionofitsenvironmentalimpact.Thosepuredemands-likeforemissiontradingareshort-sightedastheydonotbaseonanintegratedapproach.InsteadtheymerelyconsiderCO2emissionsduringtheproductionprocess.Aforward-looking,globalclimateandenvironmentalpolicyneedsasustainablelifecycleapproach.Thereforeitmustforexamplealsotakeintoaccountthecontributionofsteeltowardscuttingemissionsinitsapplication-intheenergy.automotiveandhouseholdsectors.Steelwillplayakeyroleinclimateprotection.One-thirdoftheremainingCO2reductiontargetplannedinGermanyby2020canonlybeachievedwiththehelpofinnovativesteelproductsandtheirapplications.ThisistheconclusionofanindependentstudybyTheBostonConsultingGroup（BCG）onbehalfofSteelInstituteVDEh,andGermanSteelFederation.ThestudycomparesCO2savingsfromimportantinnovativesteelapplications（suchasmoreefficientpowerstations,windturbines,orlightervehicles）withCO2emissionscausedbysteelproduction.Byadoptingthiscomprehensiveperspective,thestudyforthefirsttimeprovidesaCO2balanceforthematerialsteelbycomparingtheCO2reductionsmadepossiblethroughinnovativesteelapplicationswiththeCO2emissionsresultingfromsteelproduction.ThebalancewascalculatedonthebasisofeightselectedinnovativesteelapplicationsinGermanyfortheperiod2007to2020,wherebytheCO2emissionscausedbysteelproductionwereconsideredthroughouttheentirelifecycleoftheparticularsteeluse.Fortheselectedexamples,theuseofinnovativesteelsresultedinatotalsavingspotentialof74MtofCO2in2020.Thecalculationsarebasedonconservativeassumptions;forexamplewithoutcountingofpotentialsbyexportedsteelorbycomparisonwithcompetitivematerials.TheproductionofsteelinGermany,includingtheextractiono
简介：ThereactionofNdCl3withlithiummethylnaphthalenein1:2moleratioinTHFgeneratesblackpowder.Thepowderreactswithcyclooctatetraene（COT）inTHFtoformthetitlecomplex.[Li（THF）4Nd（C8H8）2]·2THFcrystallizesinthemonoclinicspacegroupP2/cwithunit-celldimensionsa=1.7858（7）nm,h=1.3243（4）nm,c=1.8086（6）nm.β=106.52（4）°,V=4.10nm3andDc=1.268g/cm3forZ=4.F（000）=1660,R=0.0774,Rn=0.0733.Thecomplexconsistsofdiscreteion-pairandtwoTHFmoleculesadduct.Intheanion,theneodymiumatomiscoordinatedbytwoCOTrings.ThestructureofthecationshowsthatthelithiumatomisattachedwithTHFmoleculesonly.
简介：为了减少锂离子电池正极材料与电解液的相互作用，用沉淀法在LiNi0．8Co0．2O2表面包覆一层Al2O3，并通过电化学测试、扫描电镜和X射线衍射研究其表面形貌和晶体结构。结果表明，经过表面包覆后，有效地抑制了电解液对正极材料的侵蚀，虽然初始放电容量略有降低，但循环性能明显改善；Al2O3包覆量对LiNi0．8Co0．2O2电化学性能存在影响，包覆量为0．7％（质量分数）的样品性能最优。
简介：Thesinglecrystalofthecomplex[Sc（NO3）3（H2O）2]·（15C5）hasbeenpreparedinacetonitrile.Thenewcomplexhasbeencharacterizedbyelementalanalysis,IRspectra,solubilityandmolarconductancemeasurements.ThestructureofthecomplexisdeterminedbysinglecrystalX-raydiffractionanalysis.
简介：Aseriesofnovelbluelong-lastingphosphorescencephosphorsSr6Al18Si2O37:Eu2+,RE3+(RE3+=Ho3+,Gd3+,Dy3+andPr3+)werepreparedbytheconventionalhigh-temperaturesolid-statereactioninareductiveatmosphere.TheirpropertiesweresystematicallyinvestigatedutilizingX-raydiffraction(XRD),photoluminescence,phosphorescenceandthermoluminescence(TL)spectra.ThephosphorsemittedbluelightthatwasrelatedtotheemissionofEu2+dueto5d-4ftransition.Brightbluelong-lastingphosphorescence(LLP)couldbeobservedaftertheexcitationsourcewasswitchedoff.Fortheoptimizedsample,thebluelong-lastingphosphorescencecouldlastfornearly4hinthelightperceptionofthedark-adaptedhumaneye(0.32mcd/m2).TheeffectsofRE3+ionsonphosphorescencepropertiesofthephosphorswerestudied,andtheresultsshowedthattheco-dopingofRE3+ionsgreatlyenhancedtheintensityofthepeakaround315Kwhichwasrelatedtothelonglastingphosphorescenceofthephosphorsatroomtemperatureandconsequentlyimprovedtheperformanceofthebluephosphorescencesuchasintensityandpersistenttime.
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![Synthesis and Crystal Structure of a Novel Ion-pair Complex of [Li（THF）4Nd（C8H8）<b style='color:red'>2</b>]·<b style='color:red'>2</b>THF](/image/thesis15 "Synthesis and Crystal Structure of a Novel Ion-pair Complex of [Li（THF）4Nd（C8H8）<b style='color:red'>2</b>]·<b style='color:red'>2</b>THF")
![STUDIES ON RARE EARTH COMPLEXES WITH CROWN ETHERS ⅩⅧ——Synthesis,Characterization and Crystal Structure of[Sc（NO3）3（H<b style='color:red'>2</b>O）<b style='color:red'>2</b>]·（15-Crown-5）](/image/thesis18 "STUDIES ON RARE EARTH COMPLEXES WITH CROWN ETHERS ⅩⅧ——Synthesis,Characterization and Crystal Structure of[Sc（NO3）3（H<b style='color:red'>2</b>O）<b style='color:red'>2</b>]·（15-Crown-5）")
