简介:FormorethanoneyeartheCLEOⅢexperimentattheCornellelectronpositronstorageringCESRhasaccumulatedPhysicsdatausinga4layersiliconvertexdetectorandanovelringimageCherenkovdetector,alongwithaconventionalDriftchamber,E.M.calorimeterandmuonchambers.BythetimeofCHEP2001theexperimenthasaccumulated10fb^-1ofdata,Thereadoutandmonitoringsystemscontrol,ca.400000electronicchannels.Detectorconfiguration.dataqualityandcomponentmonitoring,runcontrolareonlysomeoftheSlowControltasksthathavetobeperformed.DeployingindustrystandardssuchasCORBA(inter-platformcommunication)Java(remoteaccessviaWebbrowser)andObjectivity(eventandconstantsdatabse)asbuildingblocksofthecomputernetworkhasbeenofcentralimportance.Objectorienteddesignhasenabledtheseamlessintegrationofthemanyindividualcomponents.Inourpresentationwewilldescribeexperienceswiththisdistributedcontrolsystemandgiveareportofthemeasurestakentoobtainahighsystemavailability.
简介:Becauseofthesuccessofthediscretevortexmethodforthesimulationoflarge-scalevortexstructure.manyresearchersextendthismethodtotwo-phaseflowsimulations,especially,tothesimulationofparticledispersioninmixinglayer,whichischaracterizedbylarge-scalevortexstructure,Butthepreviousworkislimitedtoone-waycouplin,whichneglectstheeffectofparticlesonfluidflow.Inthispaperadiscretevortexmethodinvolvingtwo-waycouplingfortwo-phaseflowsisfristproposedandthenusedinnumericalsimulationoftwo-dimensionalgas-particlemixinlayersThenumericalresultsshowthattheintroductionofparticlesintothemixinglayerhassignificanteffectsonthecreation,developmentandmergingprocessoflarge-scalevortexstructures.Itmakesthemeansizeoflarge-scalevortexstucturelargeandthedistanceneededfordevelopmentoflarge-scalevortexsturctureshorter.
简介:Thearomatizationoflightalkenesinliquefiedpetroleumgas(LPG)withandwithoutdimethylether(DME)additioninthefeedwasinvestigatedonamodifiedZSM-5catalyst.Theresultsshowedthatunderthegivenreactionconditionstheselectivityofalkenestohigh-octanegasolineblendingcomponentswasmarkedlyenhancedandtheformationofpropaneandbutaneswasgreatlysuppressedwiththeadditionofDME.ItwasalsofoundthatthedistributionofC5+componentswaschangedalotwithDMEadditionintotheLPGfeed.Theformationofbranchedhydrocarbons(mainlyC6C8i-paraffin)andmulti-methylsubstitutedaromatics,whicharehighoctanenumbergasolineblendingcomponents,waspromotedsignificantly,whilethecontentofn-paraffinsandolefinsinC5+componentswasdecreasedobviously,indicatingthatinadditiontotheoligomerization,cracking,hydrogen-transferanddehydrogenation-cyclizationofalkenes,themethylationoftheformedaromaticsandolefinsintermediatesalsoplaysanimportantroleindeterminingtheproductdistributionduetothehighreactivityofsurfacemethoxygroupsformedbyDME.Andthisprocess,incombinationwiththesyngas-to-methanol/DMEtechnology,providesanalternativewaytotheproductionofhigh-octanegasolinefromcoal,naturalgasorrenewablerawmaterials.