简介:ThisstudypresentsanovelprocessofinsitusurfacemodificationofCaCChnanoparticlesusingamultipleorificedispersionmicroreactor.CO2/Ca(OH)2precipitationreactionwasemployedtoprepareCaCO3nanoparticleswithsodiumstearatesurfactant.SynthesizedCaCChproductswerecharacterizedbythermogravimetricanalysis(TGA),infra-red(IR),X-raydiffraction(XRD),transmissionelectronmicroscopy(TEM)andBrunauer-Emmet-Telleranalysis(BET).Theeffectofvariousoperationparametersonnanoparticlesandthedosageofsodiumstearateweredetermined.Theresultsshowedthatthepreparationprocesscouldbepreciselycontrolledwithefficientmasstransferprocess.Theparticleswerehighlyhydrophobicwithacontactangleof117andmonodispersewithanaveragesizeof30nm.Theadsorptionsofsodiumstearateandcalciumiononsolidparticlesduringtheinsitusurfacemodificationprocesswereinvestigated.
简介:Thespectralcharactersofhydrocarbonsinsomeoil-bearingstrataandsoillayersoueroilandgasreservoirsintheJunggarBasinandnorthernTarimBasininXinjngarecomparedwiththoseofchemicallypurehydrocarbons.Thehydrocarbonsarecharacterizedbythebi-absorptionat2310nmand2350nm.Hydrocarbonandradioactiveanomaliesinoilandgasterrainsarefoundmuchmorewidespreadthancarbonatealterations.Basedonthespectraofheavyhydrocarbonsrelatedtooilbetween2270nmand2460nmandrefineddatatreatment,remotesensingmayholdencouragingpromiseasadirectlyprospectingtechniqueforoilandgasresources.
简介:Themainpurposeofthispaperistwo-fold:(i)togeneralizeanexistenceresultforacompressiblegas-liquidmodelwithafrictiontermrecentlypublishedbyFriisandEvje[SIAMJ.Appl.Math.,71(2011),pp.2014–2047];(ii)toderiveauniquenessresultforthesamemodel.Amainingredientintheexistencepartistheobservationthatwecanconsiderweakerassumptionsontheinitialliquidandgasmass,andstillobtainanexistenceresult.Comparedtotheabovementionedwork,werelyonamorerefinedapplicationoftheestimatesprovidedbythebasicenergyestimate.Concerningtheuniquenessresult,weborrowideasfromFangandZhang[NonlinearAnal.TMA,58(2004),pp.719–731]andderiveastabilityresultunderappropriateconstraintsonparametersthatdeterminerateofdecaytowardzeroattheboundaryforgasandliquidmasses,andgrowthrateofmassesassociatedwiththefrictiontermandviscouscoefficient.
简介:AhypereutecticAl-Sialloypowderwaspreparedbyultrasonicgasatomizationprocess.Themorphologies,microstructureandphaseconstituentofthealloypowderwerestudied.TheresultsshowedthatpowderofthealloywasveryfineanditsrnicrostructurewasmainlyconsistedofSicrystalsplusintermetalliccompoundAl9FeSi3,whichwere.veryfineanduniformlydistributed.
简介:Thispaperpresentstheresultsofourinvestigationsofbreakdownmechanisms,aswellasadescriptionoftheirinfluenceonthedistributionsoftimedelaydistributions,foragastubefilledwithnitrogenat4mbar.Thevaluesofthetimedelayaremeasuredfordifferentvoltages,andthevaluesoftherelaxationtimesandtheirdistributionsandprobabilityplotsareanalyzed.TheobtaineddensitydistributionshaveGaussiandistributionsandexponentialdistributionsfordifferentvaluesofrelaxationtimes(Gaussianforsmallvaluesandexponentialforlargevaluesofrelaxationtime).ItisshownthatformiddlevaluesofrelaxationtimethedelaydistributionshaveashapebetweenGaussianandexponentialdistributions,whichisaresultofthedifferentinfluencesofelectricalbreakdown.
简介:Withanalloycontentashighas80%ormore,Ni-basedOCTGisastrategicproductsrelatedtothestateenergysecurity,mainlyappliedintheexploitationanddevelopmentofsourgasfieldswithcomplicategeologicalformation,hightemperature,highpressureandseverecorrosivewellconditions.Ni-basedOCTGisregardedasthepipeproductwithmosthightechnologiesduetothecomplexityandgreatdifficultyinmanufacturingandrigorousrequirementsinqualitycontrol.Inthispaper,thetechnicalfeaturesandqualityrequirementsofNi-basedOCTGaresummarized,andthequalityandpropertiesoftheNi-basedOCTGproductsofBaosteelareintroducedindetail.WiththehelpofSEM,XPSandTEM,thecorrosionmechanismofNickle-basedOCTGintheenvironmentscontainingH2S,CO2,Cl-andelementarysuifurarealsoanalyzed.
简介:Turbulentreactingflowsinagenericswirlgasturbinecombustormodelareinvestigatedbothnumericallyandexperimentally.Intheinvestigation,anemphasisisplacedupontheexternalfluegasrecirculation,whichisapromisingtechnologyforincreasingtheefficiencyofthecarboncaptureandstorageprocess,which,however,canchangethecombustionbehavioursignificantly.Afurtheremphasisisplacedupontheinvestigationofalternativefuelssuchasbiogasandsyngasincomparisontotheconventionalnaturalgas.FlamesarealsoinvestigatednumericallyusingtheopensourceCFDsoftwareOpenFOAM.Inthenumericalsimulations,alaminarflameletmodelbasedonmixturefractionandreactionprogressvariableisadopted.Asturbulencemodel,theSSTmodelisusedwithinaURANSconcept.Computationalresultsarecomparedwiththeexperimentaldata,whereafairagreementisobserved.
简介:IntroductionTheelectrochemicalreductionofO2wasinvestigatedwidelyduringthepasttwodecades.O2-canreactwithvariousorganiccompounds.O2-asanewsynthesisreagenthasbeenbeingexplored.
简介:Numericalsimulationofgas-solidflowinatwo-dimensionalfluidizedbedwithaninclinedjetwasperformed.Thenumericalmodelisbasedonthetwo-fluidmodelofgasandsolidsphaseinwhichthesolidsconstitutiveequationsarebasedonthekinetictheoryofgranularflow.TheimprovedICEalgorithm,whichcanbeusedforbothlowandhigh-velocityfluidflow,wereusedtosolvethemodelequations.Themechanismofjetformationwasanalyzedusingbothnumericalsimulationsandexperiments.Theemergenceandmovementofgasbubbleswerecapturednumericallyandexperimentally.Theinfluencesofjetvelocity,nozzlediameter,nozzleinclinationandjetpositiononjetpenetrationlengthwereobtained.Asemi-empiricalexpressionwasderivedandtheparameterswerecorrelatedfromexperimentaldata.Thecorrelationequation,whichcanbeeasilyusedtoobtaintheinclinedjetpenetrationlength,wascomparedwithourexperimentaldataandpublishedcorrelationequations.
简介:Wavelengthmodulationtechnique(WMT)andactiveintracavitytechnique(ACIT)arefirstintroducedinthispaper,whichareusedtorealizetheconcentrationdetectionofmethaneandacetylenerespectively.WhenACITiscombinedwithwavelengthsweeptechnique(WST),thedetectionsensitivityofacetylenecanbeenhancedsharply.WhenACITiscombinedwithWSTandWMT,thedetectionsensitivityofacetylenecanbeenhancedfurther.