简介：对两种单种煤进行工业性质、工艺性质和结焦性能检测,结果表明两种单种煤的粘结性能属中上等水平,流动性能较好。通过20kg小焦炉配煤炼焦发现,两种煤均有利于焦炭热态性能的改善,但是对于焦炭冷态性能方面,两者表现出来的作用不尽相同,官桥煤优于信诚和煤。

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简介：Duetotheremarkablemagnetoresistance(MR)effectonperovskite-typemanganite,magnetoelectronicsandspintronicshavebecomeattractivesubjectsofexperimentalandtheoreticalinvestigationsfortheapplicationpurpose.(La0.9Nd0.1)2/3Ca1/3Mn1-xFexO3(x=0,x=0.05)werepreparedsuccessfullybysol-gelmethod.Thestructure,magneticproperties,andtransportpropertiesofthecompoundswereinvestigated.Themagnetoresistanceeffectdependsonthecompositionandthetemperature.XRDpatternsshowthatthecompoundisasinglephasepolycrystalwithpseudocubicstructure.Alargenegativeisotropicmagnetoresistanceeffectinthesampleswereobservedatlowtemperatureregion.ThemaximumMRofthesampleswas77%and97%,respectively.Itwasmostlikelyduetothescatteringorthetunnelingtransportofspin-polarizedcarriersinlatticeunderstrongmagneticfield.

简介：Er3+/Yb3+codopedzincateBaGd2ZnO5phosphorsweresynthesizedviaatraditionalsolidstatereaction.ThecrystalstructureandphasepuritywerecheckedbymeansofX-raydiffraction(XRD),andtheresultsshowedthatpurephaseBaGd2ZnO5phosphorswithvariousEr3+,Yb3+concentrationswereobtained.TheinfluenceofEr3+andYb3+dopingconcentrationsonthegreenandredupconversionemissionswasstudied.Itwasfoundthatbothgreenandredupconversionemissionsunder980nmexcitationweretwo-photonprocessesindependentfromtherareearthdopingconcentrations.However,theupconversionluminescenceintensitiesgreatlydependedontherareearthdopingconcentration.Furthermore,thepopulationprocessesofupconversionluminescenceandthequenchingmechanismswereanalyzed.Thetemperature-dependentgreenupconversionluminescencewasstudied,andthetemperaturequenchingprocessoftwogreenupconversionemissionswasmodeled.Thethermalquenchingprocessesofthegreenupconversionemissionscouldbewellexplainedbythemodelweproposed.

简介：ThephaseandmorphologytransformationduringthehydrothermaltreatingprocessofY2O3wasevaluatedwithX-raydiffcrcnce(XRD),scanningelectronmicroscopy(SEM),transmissionelectronmicroscopy(TEM),particlesizeandspecificsurfaceareadetermination.TheresultsshowedthatthecubicY2O3didnottransferintohexagonalY(OH)3inpurewater.Therefore,purehexagonalY(OH)3withnanotubeandmicrorodmorphologieswereobtainedbyhydrothermaltreatingY2O3at150℃for12hin15mlof2mol/LNaOHsolutionwithandwith-outPVAorPEGItwassuggestedthatthecharacteristicpreferentialgrowthofY(OH)3wasattributedtothestructureanisotropyofhexahedronY(OH)3.TheadditionofPVAorPEGcouldpromotetheformingprocessofnanotubesbyselectiveadsorptionondifferentcrystalplanes,whichalteredthegrowthratealongdifferentdirectionsandresultedinthediffusionlimitofconstructingionsinthecentertopofrods.Finally,Y(OH)3:EuandY2O3:Eunanotubeswerealsosynthesizedbyusingthismethod,andtheirphotoluminescencepropertieswereevaluated.

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简介：ThemeasurementsoftemperaturedependenceofthemagneticsusceptibilityofLa1-xSrxCoO3perovskiteoxidesatdifferentSrdoping(0≤x≤0.5)andannealingtemperaturewerepresented.Forthesamplewithx=0.1,ashoulderwasobservedaround150K,andapeakwhichisonefeatureofspinglassappearedaround50Kinthecurveofsusceptibilityversustemperature.Thehigh-temperature(250～420K)susceptibilityfitswellwithCurie-Weisslawforallsamples.WeissconstantandeffectivemagneticmomentweredeterminedandtheirvariationswithSrdopingandoxygenannealingconditionwereobtained.TheWeissconstantincreasesmonotonouslywithSrcontentforx>0.2.Thevaluesofeffectivemomentswereinterpretedwiththespinstateofcobaltions.Studiesonthesusceptibilitiesofthesampleswithx=0.2underdifferentpreparationtemperaturesandannealingtemperaturesshowthattherisingofsinteringtemperatureandannealingtemperaturewillincreasethepara-ferromagnetictransitiontemperature,andreducetheeffectivemomenttonormalvalue.OurresultshowsthatbothCo3+andCo4+ionsshouldbeinISstateafterannealingandtheoxygenannealingcausesthetransitionofCo3+spinstatefromHStoIS.

简介：Thesinglecrystalofthecomplex[Sc（NO3）3（H2O）2]·（15C5）hasbeenpreparedinacetonitrile.Thenewcomplexhasbeencharacterizedbyelementalanalysis,IRspectra,solubilityandmolarconductancemeasurements.ThestructureofthecomplexisdeterminedbysinglecrystalX-raydiffractionanalysis.

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：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。该法分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

简介：黄磷(Bi1-xSmx)2ZnB2O7(x=0.01，0.03，0.05，0.07，和0.09)被常规稳固的州的反应综合。所有样品的纯净被X光检查粉末衍射(XRD)检查。XRD分析证明所有这些混合物具有Bi2ZnB2O7的一个单个阶段，显示在Bi2ZnB2O7的双性人(3+)能被没有晶体结构的变化的Sm(3+)部分代替。在房间温度的刺激和排放系列显示出Sm(3+)的典型4f-4f转变。主导的刺激线在404nm附近由于(6)H5/2→(4)K11/2和排放光谱在563，599，646，和704nm由一系列线组成由于(4)G5/2→(6)H5/2，(6)H7/2，(6)H9/2，并且(6)H11/2分别地。在Bi2ZnB2O7的Sm(3+)的最佳的集中关于3mol%(相对1mol双性人(3+))并且批评距离Rc作为2.1nm被计算。Bi1.94Sm0.06ZnB2O7的排放紧张的温度依赖在在100和450K之间的温度范围被检验。紧张下降了到起始的紧张的一半的熄灭的温度是280K。为在Bi1.94Sm0.06ZnB2O7的Sm(3+)的一生作为0.29和1.03ms的价值被适合。

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简介：TheZrO2-Al2O3ceramiccompositeswerepreparedbyappropriatetechniqueswithcommercialZrO2andAl2O3powdersasrawmaterialsandY2O3asstabilizer.TheresultsindicatethatwiththeintroductionofAl2O3intotheZrO2matrixwherethequantityofadditiveY2O3is3.5%(molefraction),thegrowthofZrO2grainsisefficientlyinhibited,whichhelpstheZrO2grainsexistinametastabletetragonalmanner;thushigherstrengthandtoughnessareacquired.Whenthecontentofaluminais20%(massfraction),thebendingstrengthandfracturetoughnessofthecompositesare676.7MPaand10MPa·m1/2respectively,themechanicalbehaviorsareclosetothosepreparedwithZrO2andAl2O3powderssynthesizedthroughwetchemicalapproach.Themechanicalbehaviorsofthecompositesarewellimprovedowingtothedispersiontougheningofaluminagrainsandphasetransformationtougheningofzirconiagrains.

简介：作为报导Y2O2S的改进:Tb3+，白光的长持续的黄磷：Y2O2S:Tb3+，Sm3+被准备由固态反应。光致发光系列证明在紫外刺激下面的Tb3+和Sm3+排出物的位置和形状在这位主人是类似的，它在不同刺激下面保证了一种稳定的白排放颜色(IEC的日光标准)。共同做的样品的腐烂曲线显示二个离子的排出物的腐烂时间是靠近的。热照明测量建议做的Sm3+离子创造的陷井是有用的推迟共同做的样品的白晚霞。因此，共同做的Sm3+离子的功能作为改进样品的白排放颜色并且充当新陷井中心被证实。

简介：介绍了武山铜矿中段运输系统原3m3底侧卸矿车的设计特点。结合生产实际状况，对3m3底侧卸矿车在运行过程中出现的问题进行了分析，总结产生故障的原因，针对性的提出改进措施。现场使用表明，通过改进后，取得了良好效果，满足了矿山生产的需要。

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简介：以异丙醇铝为前驱体，HNO3为胶溶剂，采用溶胶-凝胶法制备Al2O3膜。考察HNO3浓度对溶胶及薄膜的影响，通过TG-DTG，XRD，AFM，BET等表征手段对溶胶的稳定性及黏度，薄膜的热稳定性，物相组成，表面形貌，微孔结构及分布等进行综合分析。结果表明：随HNO3浓度增大，溶胶黏度增大，HNO3浓度为5mol/L时溶胶发生团聚；薄膜的热稳定性较好，高于500℃加热薄膜几乎没有质量损失；随烧结温度升高，薄膜中的γ-AlOOH逐渐向γ-Al2O3转变，薄膜因此变得更加稳定；薄膜表面较为平整，微孔分布均匀，平均孔直径为4.22nm。

简介：Er~（3＋）andLa~（3＋）codopedY_2O_3nanocrystallinepowdersweresynthesizedbygelcombustionmethodandcharacterizedwiththermalanalysis,X-raydiffraction（XRD）,transmissionelectronmicroscopy（TEM）,high-resolutionTEM（HRTEM）techniquesandfluorescencespectroscopy.Afterbeingcalcinedat1200oC,the（Y_（1–x）La_x）_2O_3：Er~（3＋）powderswereconfirmedtobecubicY_2O_3phasewiththecrystallinegrainsizeintherangeof20–40nm.TheEr~（3＋）emissionat1.53μmfromthe~4I_（13/2）→~4I_（15/2）transitionwasobserved,whichwasfoundtobeenhancedbyintroducingLa~（3＋）ions.SuchenhancementcouldbeattributedtotheadjustmentofEr~（3＋）ions＇localenvironmentbythecodopingofLa~（3＋）ions,leadingtotheincreasedgroundstateabsorptioncrosssectionofEr~（3＋）ions.

简介：阐述自增韧Al2O3陶瓷的增韧原理及增韧机制，综述近年来Al2O3陶瓷的自增韧研究现状。指出Al2O3陶瓷的自增韧方式可以分为引入添加剂和引入晶种2种，并详细论述了不同添加剂、不同晶种及引入方式对Al2O3晶粒异向生长及其力学性能的影响，分析了不同条件下Al2O3晶粒的显微结构及其异向生长机理。最后对下一步的研究方向进行了展望。