简介:Praseodymium(Pr)wasimpregnatedtoCeO2-ZrO2solidsolutionbyanimpregnationmethod.Theas-obtainedPrmodifiedCeO2-ZrO2wasimpregnatedwith1wt.%Pdtopreparethecatalysts.ThestructureandreducibilityofthefreshandhydrothermallyagedcatalystswerecharacterizedbyX-raydiffraction(XRD),Raman,X-rayphotoelectronspectroscopy(XPS),COchemisorptionandH2temperature-programmedreduction(H2-TPR).Theoxygenstoragecapacity(OSC)wasevaluatedwithCOservingasprobegas.EffectsofimpregnatedPronthestructureandoxygenstoragecapacityofcatalystswereinvestigated.TheresultsshowedthattheagedPr-impregnatedsampleshadmuchhigherOSCandbetterreducibilitythantheunmodifiedones.TheschemeofstructuralevolutionsofthecatalystswithandwithoutPrwasalsoestablished.PartialoftheimpregnatedPrdiffusedintothebulkofCeO2-ZrO2duringageing,whichinhibitedthesintering,andincreasedtheamountofoxygenvacanciesinCeO2-ZrO2support.Furthermore,thoseimpregnatedPrspecieswhichcoveredonthesurfaceofthesupportobstructedthestrongmetal-supportinteractionbetweenPdandCesoastoreducetheencapsulationofPdaswellasthebackspill-overoftheoxygenduringthecatalyticprocess.
简介:摘要院伴随当前汽车市场的不断成熟,客户在对汽车的消费过程中产生越来越高的要求,同时也越来越严格。在经济飞速发展的今天,汽车已经成为人们生活中的必需品,同时汽车在品牌方面的归口管理需求也迫切需要汽车4S店的产生。因此,汽车4S店是一种必然的发展趋势。本文将重点对汽车销售4S店的财务核算和管理进行分析,从而为汽车4S店的高效运营提供决策参考。
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简介:ChinaandtheU.S.haveinitiatedaseriesofbilateralandmultilateralactionstodealwiththeNorthKoreannuclearcrisis.Inthelong-term,bilateralcooperationwilldependonPyongyang’sactions,U.S.attitudeonthenuclearissue,NorthKorea’spositioninChina’sgrandstrategyaswellasthebalancebetweenSino-U.S.strategiccompetitionandcooperation.
简介:Thepost-earthquakerapidaccurateassessmentofmacroinfluenceofseismicgroundmotionisofsignificanceforearthquakeemergencyrelief,post-earthquakereconstructionandscientificresearch.TheseismicintensitydistributionmapreleasedbytheLushanearthquakefieldteamoftheChinaEarthquakeAdministration(CEA)fivedaysafterthestrongearthquake(M7.0)occurredinLushanCountyofSichuanYa’anCityat8:02onApril20,2013providesascientificbasisforemergencyrelief,economiclossassessmentandpost-earthquakereconstruction.Inthispaper,themeansforblindestimationofmacroscopicintensity,fieldestimationofmacrointensity,andreviewofintensity,aswellascorrespondingproblemsarediscussedindetail,andtheintensitydistributioncharacteristicsoftheLushan'4.20'M7.0earthquakeanditsinfluentialfactorsareanalyzed,providingareferenceforfutureseismicintensityassessments.
简介:AftertheendoftheColdWar,theClintonadministrationemployedapolicyof‘engagementandintegration’towardsChina,anapproachwhichevolvedanddeepenedintheBushandObamagovernments.TheObamaadministrationhasmadesubstantialadjustments,highlightingthedualnatureofSino-U.S.relationshipwithbotha"highdegreeofcooperation"anda"highlevelofcompetition."
简介:Kartagener’s综合征(kartagener’ssyndrome,KS)由支气管扩张、慢性鼻窦炎或鼻息肉、内脏反位三联征组成。主要表现为反复发生呼吸道化脓性感染、咯血为特征的支气管扩张症状及副鼻窦炎和右位心。笔者结合1例近期诊治患者并文献复习,现报告如下。
简介:Theresearchproject'DevelopmentandapplicationofFCCadditiveformaximizationofpropyleneandisobutylene'jointlyundertakenbyRIPP,theBalingPetrochemicalCompany(BPC)andtheSINOPECCatalyst
简介:摘要院起源于日本的“5s”管理,是指在对生产现场的生产要素,如人员、机器、材料和方法等进行的有效管理,这是日本企业独特的一种管理办法。由于应用此方法能够有效推动企业的良好发展,因此,现在已广泛应用于我国的各类型企业中,但是以职业技能教育为主的高职学院各类实训中心却少有应用,本文将介绍“5S”管理的作用及如何应用于实训中心教学管理中。
简介:目的探讨中老年人纹状体和黑质1H—MRS各参数值正常参考范围。方法纳入健康中老年志愿者32名,采用单体素PRESS序列对纹状体、多体素PRESS序列对黑质进行1H—MRS扫描,分析N-乙酰天门冬氨酸(NAA)、胆碱(Cho)和肌酸(Cr)含量及各参数比值。结果左右侧纹状体和黑质NAA/Cr、Cho/Cr、NAA/Cho、NAA/(Cho+Cr)差异均无统计学意义(P均〉0.05)。综合两侧结果,纹状体NAA/Cr、Cho/Cr、NAA/Cho、NAA/(Cho+Cr)均值及95%C1分别为1.39(1.33~1.45)、0.90(O.86~0.94)、1.58(1.50~1.66)、0.73(0.70~O.76);黑质上述比值均值及95%C1分别为2.36(1.85~2.87)、1.38(1.12~1.65)、1.70(1.59~1.81)、0.93(0.86~1.00);纹状体及黑质中NAA/(Cho+Cr)比值均最稳定。结论正常中老年人黑质和纹状体’H—MRS各参数中,NAA/(Cho+Cr)比值最稳定,可为研究累及黑质和纹状体区域的疾病提供正常参照。
简介:AhighlyefficientH1-Galerkinmixedfiniteelementmethod(MFEM)ispresentedwithlineartriangularelementfortheparabolicintegro-differentialequation.Firstly,somenewresultsabouttheintegralestimationandasymptoticexpansionsarestudied.Then,thesuperconvergenceoforderO(h2)forboththeoriginalvariableuinH1(π)normandthefluxp=uinH(div,π)normisderivedthroughtheinterpolationpostprocessingtechnique.Furthermore,withthehelpoftheasymptoticexpansionsandasuitableauxiliaryproblem,theextrapolationsolutionswithaccuracyO(h3)areobtainedfortheabovetwovariables.Finally,somenumericalresultsareprovidedtoconfirmvalidityofthetheoreticalanalysisandexcellentperformanceoftheproposedmethod.