简介：EffectsoftheorientationandapexangleonthesettlingvelocityofconicalparticlesinBinghamplas-ticfluidsarenumericallyinvestigatedoveraReynoldsnumberrangeof1≤Re≤100,Binghamnumberrangeof0≤Bn≤100,andconeanglerangeof20≤α≤150°.Governingequations(ofcontinuityandmomentum)aresolvednumericallyusingthefiniteelementmethodtoobtainvelocityandpressurefieldsthatarepostprocessedtoobtainvaluesofthedragcoefficien.Futthermore,theeffectofconeori-entationontheflowfieldisvisualizedandexploredintermsofstreamlinecontoursandthemorphologyofyielded/unyieldedregions.Finally,theobtainedvaluesofdragarecorrelatedviaasimplepredictiveexpressionintermsofthemodifiedReynoldsnumber.Theeffectoftheconeangleondragisfoundtobemoderatebecausethedragforceactingonthelateralsurfaceisasmallfractionoftheoveralldrag.

简介：Tetraphenylporphyrin(TPP)isatypicalred-emittingluminogenshowingevidentaggregationcausedquenching(ACQ)effect.Toenhanceitsemissionefficiencyinsolidstate,fourtetraphenylethene(TPE)unitswereattachedtothefourmeso-positionsofTPPcoreviaestergroupthroughafacileandefficientroute.Thederivedcompound(4(TPE-COO)-TPP)emitsredfluorescence(peakat655nm)withagoodquantumefficiency(F)of7.5%,whichismuchhigherthanthatofTPP(Φ~0.1%).Inmolecularaggregateformedintetrahydrofuran(THF)andwatermixtures,4(TPE-COO)-TPPhasarelativehighFof12%.TheevidentlysubduedACQbehaviorcanbeascribedtothepropellershapeandbulkysizeoftheTPEunits,whichpreventtheclosepackingandstrongp-pinteractionofTPPcores.TheloosemolecularpackingandweakinterchromophoreinteractionswerevalidatedbydifferentcharacterizationmethodsincludingUV-visibleabsorption,steadystateandtransientfluorescencespectroscope,X-raydiffractionandscanningelectronicmicroscopeobservations.Itisnotedthat4(TPE-COO)-TPPhasanemissionefficiencyof14.4%indiluteTHFsolution.ThisisduetotheconjugationbreakbetweentheTPPandTPEmoieties,therotationalandvibrationalmotionsofthephenylgroupscannotquenchthefluorescenceof4(TPE-COO)-TPP.

简介：Inthiswork,theborescopicparticleimagevelocimetry(BPIV)techniquewasappliedtoabubblinggas-solidfluidizedbed,andtheresultswerecomparedwithpublishedpositronemissionparticletracking(PEPT)measurementdata.Beforeperformingtheexperiments,thesensitivityoftheBPIVresultstotheilluminationpower,lightreflectivityoftheparticles,andlocationoftheborescopewasalsoinvestigated.TheBPIVandPEPTresultswereinfairagreement;however,somediscrepancieswereobserved.ThedifferencebetweenthetwosetsofresultsweremainlycausedbytheintrusivenessofBPIV,thefactthatthelocalsolidsvolumefractionwasnotaccountedforintheBPIVanalysis,andtheintrinsicdifferencesofthesetwomethods.Therefore,measurementofthelocalsolidsvolumefractionwiththeborescopeishighlyrecommendedforfurtherdevelopmentoftheBPIVmethod,whichwillalsoenablemeasurementofthelocalsolidsmassfluxesinsidedensegas-solidfluidizedbeds.

简介：Immisciblefluidflowisfrequentlyfoundinresourcerecoveryorsoilremediation.Theflowpatternintheporousmediaisaffectedbythewettabilityofporesurface.Inthisstudy,quartzsubstratesandmicrofluidicchipsaretreatedbysilicananoparticles(SNP)andtriethoxy(octyl)silane(TES)tofabricatethewater-wetandoil-wetsurfaces.Thewettabilityofthetreated-surfaceismeasuredintermofcontactangleforseveralcombinationsofsurroundingfluidandaliquiddroplet.Theeffectofthewettabilityonthefluidflowpatternisexploredbyinjectingoilandwateralternatelyintothesurface-treatedmicrofluidicchips.TheresultsrevealthattheSNP-coatedquartzsubstrateshowsstrongwater-wetpropertyandtheTEScoatingmakeswater-repellent/oil-wetsurfaces.Inaddition,itisfoundthatthemaximumandminimumoilandwatersaturationduringalternateinjectionofoilandwaterdependsonthesurfacewettabilityofthemicrofluidicchips.Thecharacteristicsofthepore-scalefluidflowpatternarealsodescribed.

简介：Theharmonysearchalgorithmisappliedtooptimumdesignsofafunctionallygraded(FG)-carbonnanotubes(CNTs)-reinforcedpipesconveyingfluidsubjectedtomovingload.ThestructureismodelledbyReddycylindricalshelltheoryandthefinalequationsareobtainedbyprincipalofHamilton.Basedondifferentialquadraturemethod(DQM),thedynamicdisplacementofsystemisderived.

简介：Asloshingmitigationconcepttakingadvantageoffloatinglayersofsolidfoamelementsisproposedinthepresentstudy.Physicalexperimentsarecarriedoutinaliquidtanktoinvestigatethehydrodynamicmechanismofthisconcept.Effectsofthefoam-layerthickness,excitationamplitude,andexcitationfrequencyonthesloshingpropertiesareanalyzedindetail.Itisfoundthatthefloatinglayersofsolidfoamelementsdonotevidentlyaffectthefundamentalnaturalsloshingfrequencyoftheliquidtankevidentlyamongtheconsideredcases.Attheresonantcondition,themaximumwaveheightanddynamicpressurearegreatlyreducedasthefoam-layerthicknessincreases.Higher-orderpressurecomponentsonthetanksidegraduallyvanishwiththeincreaseofthefoam-layerthickness.Caseswithdifferentexcitationamplitudesarealsoanalyzed.Thephenomenonisobservedwhenthewavebreakinginthetankcanbesuppressedbysolidfoamelements.

简介：Becauseoftheexcellentmechanicalpropertiesof34C「NiMo6steel,itiswidelyusedinhigh-valuecomponents.Manyconventionalapproachestostrengthening-steelstypicallyinvolvethelossofusefulductility.Inthisstudy,34CrNiMo6Steelhavinghighstrengthandductilityisproducedbylasersolidforming(LSF)w让haquenching-tempering(QT)treatment.TemperingofbainiteismainlybysolidphasetransformationinthepreviousLSFlayersduringtheLSFprocess.ThestablemicrostructureofLSFconsistsofferriteandfinecarbides.Themicrostructuretransferstotemperedsorbiteafterheat-treatment.ThetensilepropertiesoftheLSFsteelmeetthoseofthewroughtstandard.TheUTSandelongationofLSFsampleat858MPa,19.2%,respectively,aregreaterthanthoseofthewrought.TheQTtreatmentenhancedtheultimatetensilestrengthandyieldstrengthoftheLSFsample.Theultimatetensilestrength,yieldstrength,reductioninarea,andelongationoftheLSF+QTsampleat980MPa,916MPa,58.9%,and13.9%,respectively,aregreaterthanthoseofthewroughtstandard.TheyieldstrengthoftheLSF+QTsampleisapproximately1.27timesthatofthewrought.TheLSFsamplesfailedinaductilefracturemode,whiletheLSF+QTsamplesshowedmixed-modefailure.ThedefectshaveonlyasmalleffectonthetensilepropertiesowingtotheexcellentductilityoftheLSFsample.

简介：Experimentswereconductedtoinvestigatetheeffectofaddingfinesonthetribo-chargingofcoarseglassbeads.Fourtypesoffines,i.e.,copper,stainlesssteel,uncoatedandsilver-coatedfineglassbeads,mixedw让h240-830μmglassbeadswereconveyedbyairthroughastainless-steelspiralpipeactingasatribo-charger.Regardlessofthetypeorelectricalconductivityofthefineparticlestested,addingsmallamountsoffines(upto10wt%)tocoarseglassbeadsresultedinasharpincreaseinthemassandsurfacechargedensitiesoftheparticles.Ingeneral,theprofilesofthemassandsurfacechargedensidesofthefine-coarseparticlemixturesasafunctionofthemixturecompositionweredeterminedbytherelativemagnitudeofcontactpotentialdifferencesandthetotalsurfaceareasofallthecomponents.Thedominantparticletribo-electrificationmechanismswitchedfromcoarseparticle-wallcontactstofineparticle-wallcontactswhenthefinesweightpercentageinthemixtureexceeded10%.Amodelwasdevelopedtopredictthemasschargedensityofbinarymixturesasafunctionofthemixturecomposition.

简介：Wedevelopatheoreticalmodelforpredictingtheultrasonicattenuationintheliquid-solidsystemcontainingmixedparticles.Theultrasonicattenuationcoefficientisobtainedbycountingthenumberofphononsthatreachthereceiver.UsingtheMonteCarlomethod(MCM),numericalsimulationswereperformedtopredicttheultrasonicattenuationswithnotonlyasingleparticletypebutalsomonodisperseandpolydispersemixedparticles.Thesimulationresultsforthesystemswithasingleparticletypewerecomparedwithvariousstandardmodels.Theresultsshowthattheyagreewellatrelativelylowparticlevolumeconcentrations(within10%).Forsystemswithmixedparticles,theparticlevolumeconcentrationwasfoundtoincreasetoaround10%,andthevariationoftheultrasonicattenuationagainstthemixingratioyieldsanonlineartrend.Moreover,theultrasonicattenuationissignificantlyaffectedbyparticleproperties.Thenumericalresultsalsoshowthatboththeparticletypeandparticlesizedistributionshouldbecarefullytakenintoaccountinthedispersionswithpolydispersemixedparticles,wheretheMCMcangiveamoredirectdescriptionofthephysicsofsoundpropagationcomparedwiththeconventionalmodels.

简介：Systemictoxicityandinsufficientdrugaccumulationatthetumours让earemainbarriersinchemotherapy.Thermosens让iveliposomes(TSL)combinedwithhighintensityfocusedultrasound(HIFU)hasemergedasapotentialsolutiontoovercomethesebarriersthroughtargeteddrugdeliveryandlocalisedrelease.Owingtothemultiplephysicalandbiochemicalprocessesinvolvedinthiscombinationtherapy,mathematicalmodellingbecomesanindispensabletoolfordetailedanalysisofthetransportprocessesandpredictionoftumourdruguptake.Tothisend,amultiphysicsmodelhasbeendevelopedtosimulatethetransportofchemotherapydrugsdeliveredthroughacombinedHIFU-TSLsystem.Allkeydeliveryprocessesareconsideredinthemodel;theseineludeinterstitialfluidflow,HIFUacoustics,bioheattransfer;drugreleaseandtransport,aswellastumourdruguptake.Thecapabilityofthemodelisdemonstratedthroughitsapplicationtoa2-Dprostatetumourmodelreconstructedfrommagneticresonanceimages.Ourresultsnotonlydemonstratethefeasibilityofthemodeltosimulatethiscombinationtherapy,butalsoconfirmtheadvantageofHIFU-TSLdrugdeliverysystemwithenhancementofdrugaccumulationintumourregionsandreductionofdrugavailabilityinnormaltissue.ThismultiphysicsmodellingframeworkcanserveasausefultooltoassistinthedesignofHIFU-TSLdrugdeliverysystemsandtreatmentregimenforimprovedanticancerefficacy.

简介：Shingledmagneticrecording(SMR)caneffectivelyincreasethecapacityofharddiskdrives(HDDs).HostawareSMR(HA-SMR)isexpectedtobemorepopularthanotherSMRmodelsbecauseofitsbackwardcompatibilityandnewSMR-specificAPIs.However,anHA-SMRdriveoftensuffersperformancedegradationunderwrite-intensiveworkloadsbecauseoffrequentnon-sequentialwritesbufferedinthediskcache.Thenon-sequentialwritesmainlycomefromupdatewrites,smallrandomwritesandout-of-orderwrites.Inthispaper,weproposeahybridstoragesystemcalledROCOwhichaimstouseasolidstatedrive(SSD)cachetoimprovetheperformanceofanHA-SMRdrive.ROCOreordersout-of-orderwritesbelongingtothesamezoneandusestheSSDcachetoabsorbupdatewritesandsmallrandomwrites.WealsodesignadatareplacementalgorithmcalledCREAfortheSSDcache.CREAfirstconductszone-orientedhot/colddataidentificationtoidentifycold-cachedzonesandhot-cachedzones,andthenevictsdatablocksbelongingtocolderzoneswithhigherprioritiesthatcanbesequentiallywrittenorwrittenthroughhost-sideread-modify-writeoperations.Itgivesthelowestprioritytodatablocksbelongingtothehottest-cachedzonethathavetobenon-sequentiallywritten.ExperimentalresultsshowthatROCOcaneffectivelyreducenon-sequentialwritestotheHA-SMRdriveandimprovetheperformanceoftheHA-SMRdrive.

简介：Aone-dimensional(1D)fluidsimulationofdualfrequencydischargeinheliumgasatatmosphericpressureiscarriedouttoinvestigatetheroleofthesecondaryelectronemissiononthesurfacesoftheelectrodes.Inthesimulation,electrons,ionsofHe+andHe2+,metastableatomsofHe*andmetastablemoleculesofHe*2areincluded.Itisfoundthatthesecondaryelectronemissioncoefficientsignificantlyinfluencesplasmadensityandelectricfieldaswellaselectronheatingmechanismsandionizationrate.TheparticledensitiesincreasewithincreasingSEEcoefficientfrom0to0.3aswellasthesheath’selectricfieldandelectronsource.Moreover,theSEEcoefficientalsoinfluencestheelectronheatingmechanismandelectronpowerdissipationintheplasmaandbothofthemincreasewithincreasingSEEcoefficientwithintherangefrom0to0.3asaresultofincreasingofelectrondensity.

简介：Thelargesize,crack-freeZr55Cu30Al10Ni5bulkmetallicglass(BMGs)withthediameterof54mmandtheheightof15mmwasbuiltbylasersolidformingadditivemanufacturingtechnology,whosesizeislargerthanthecriticaldiameterbycasting.Themicrostructure,tensileandcompressivedeformationbehaviorsandfracturemorphologyoflasersolidformedZr55Cu30Al10Ni5BMGswereinvestigated.Itisfoundthatthecrystallizationmainlyoccursintheheat-affectedzonesofdepositionlayers,whichconsistofAl5Ni3Zr2,NiZr2,ZrCu,CuZr2phases.Thecontentofamorphousphaseinthedepositisabout63%.Underthecompressiveloading,thedepositpresentsnoplasticitybeforefractureoccurs.Thefractureprocessismainlycontrolledbytheshearstressandthecompressiveshearfractureanglesofabout39.Thecompressivestrengthreaches1452MPa,whichisequivalenttothatofas-CastZr55Cu30Al10Ni5BMGs,andthereexistvein-likepatterns,river-likepatternsandsmoothregionsatthecompressivefractography.Underthetensileloading,thedepositpresentsthebrittlefracturepatternwithoutplasticdeformation.Thefractureprocessexhibitsnormalfracturemodel,andthetensileshearfractureangleofabout90°.Thetensilestrengthisonlyabout609MPa,andthetensilefractographymainlyconsistsofmicro-scaledcoresandvein-likepatterns,dimple-likepatterns,chocolate-likepatternsandsmoothregions.Theresultsfurtherverifiedthefeasibilityandlargepotentialoflaseradditivemanufacturingonfabricationandindustrialapplicationoflarge-scaleBMGsparts.

简介：摘要 义 184-斜 7井是位于济阳坳陷沾化凹陷渤南洼陷中部断阶带的一口注气井，该井面临着上部地层造浆严重，东营底部、沙河街易垮塌，沙四段地层压力系数高且密度窗口窄的难题。在经过对各地质层位深入研究并和邻井对比分析后，制定了合理的钻井液技术措施，该井于 2018年 11月 6日 6:00钻至井深 4133m三开完钻。钻进过程中二开转换泥浆体系是关键，三开钻井液流变性调整是重点，并且高密度钻井液性能维护不同于常规钻井液，助剂配伍性要好，而且加量要及时、均匀而充足，保证其有效含量，形成优质泥饼，从而降低失水和摩阻，确保井壁稳定、防止复杂事故的发生。

简介：Thepulsed-sprayfluid-bedgranulation(PSFBG)processwasinvestigatedandoptimizedusingdefinitivescreeningdesign,arecentlyproposednewclassofthree-leveldesignofexperimentmethod.Suchadesignenabledquadraticmodelstobeestablishedthatdescribedtheeffectofsixinputprocessparameters-inletairtemperature,inletairhumidity,bindersprayrate,atomizationpressure,pulseperiod,andpulsewidth-onthegranulequalityinaPSFBGprocess.Mathematicalmodelsofthemeanparticlesize,relativesizedistributionwidth,productionyield,andporosityweredevelopedtoquantifytherelationshipsbetweentheinfluencingfactorsandcriticalqualityattributes.Onthebasisofconstraintsonthedesiredgranuleproperties,adesignspaceforPSFBGwasdeterminedandrangesoftheoperatingparametersweredefined.Anacceptabledegreeofpredictionwasconfirmedbyvalidationexperiments,demonstratingthereliabilityandeffectivenessofusingdefinitivescreeningdesigntostudythePSFBGprocess.Thismethodcanacceleratescreeningandoptimizationofthisprocesswithinalargemultidimensionaldesignspace.

简介：Thesuppressionoftherecombinationofelectronsandholes(e–h)andtheenhancementofthelightabsorptionofsemiconductorsaretwokeypointstowardefficientphotocatalyticdegradation.Here,wereportafew-layerg-C3N4/α-MoO3nanoneedles(flg-C3N4/α-MoO3NNs)all-solid-stateZ-schememechanismphotocatalystsynthesizedviaatypicalhydrothermalmethodinacontrolledmanner.Therecombinationofthephoto-inducede–hpairscouldbeeffectivelyrestrainedbytheZ-schemepassagewaybetweentheflg-C3N4andα-MoO3NNsinthecomposite,whichcouldalsopromiseahighredoxabilitytodegradepollutants.Anditbecamepossibleforthepreparedphotocatalysttoabsorblightinawiderangeofwavelengths.Thedetailedmechanismwasstudiedbyelectronspin-resonancespectroscopy(ESR).Thelow-dimensionalnanostructureofthetwoconstituents(α-MoO3NNswithone-dimensionalstructureandflg-C3N4withtwo-dimensionalstructure)endowedthecompositewithvarietiesofexcellentphysicochemicalproperties,whichfacilitatedthetransferanddiffusionofthephotoelectronsandincreasedthespecificsurfaceareaandtheactivesites.The10wt%flg-C3N4/α-MoO3NNsshowedthebestphotocatalyticperformancetowardRhBdegradation,therateofwhichwas71.86%,~2.6timeshigherthanthatofα-MoO3NNs.