简介：Aseriesofbiodegradablehydrogelsbasedondextranandpoly(L-glutamicacid)werefabricatedforeffectivevancomycinloadingandrelease.Thepreparationofhydrogelswassimplyachievedbyphotocross-linkingofmethacrylateddextranandpoly(L-glutamicacid)-g-hydroxyethylmethacrylate(PGH)inthepresenceofphotoinitiatorI2959.ThestructuresofhydrogelswerecharacterizedbyFTIRandSEM.Theswellingandenzymaticdegradationbehaviorsofhydrogelswereexaminedtobedependentonthepoly(L-glutamicacid)contentinthehydrogels.Thehighercontentofpoly(L-glutamicacid)inthegel,thehigherswellingratioandquickerdegradationwereobserved.Moreinterestingly,thehydrogelwithhigherPGHratioshowedhighervancomycin(VCM)loadingcontent,whichmightbeduetotheelectrostaticinteractionbetweencarboxylategroupsinhydrogelandammoniumgroupofVCM.InvitrodrugreleasefromtheVCM-loadedhydrogelsinaqueoussolutionexhibitedsustainedreleaseofVCMupto72h,whiletheinvitroantibacterialtestbasedontheVCM-loadedhydrogelshowedanefficientMethicillin-ResistantS.aureus(MRSA)inhibitionextendingoutto7days.Theseresultsdemonstratedthatthebiodegradablehydrogelswhichformedbyinsituphoto-crosslinkingwouldbepromisingasscaffoldsorcoatingsforlocalantibacterialdrugreleaseintissueengineering.

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简介：Inbiosciencepapers,besidestheotherscientificmisconductissues,replicationofthemethodsectionisacommonproblembecauseduplicationisalwaysbeingdetectedinthesectionMaterialsandMethods.Weeditorsoftenreceivecommentsandqueriesfromauthorswhothinkthatitisamatterofcoursetocopytheirownpublishedmaterialsasopposedtocopyingthoseofothers.Howshouldeditorshandlesuchpaperswithsimilarcontentinthemethodsectionandhowtoguideauthorsinwritingthemethodsectionwithoutbeingaccusedofplagiarism?Whatisright?Whatiswrong?Herewestudiedanexampletoexplainthisproblem.

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简介：Inthisarticle,weestablishtheglobalstabilityofanendemicequilibriumofmulti-groupSIRepidemicmodels,whichhavenotonlyanexchangeofindividualsbetweenpatchesthroughmigrationbutalsocrosspatchinfectionbetweendifferentgroups.Asaresult,wepartiallygeneralizetherecentresultinthearticle[16].

简介：Basedonthermogravimetricanalysis,kineticparametersofShenhuacoal,suchasactivationenergyandfrequencyfactorhavebeengotfromtheTG/DTGresults.Itshowedthatactivationenergyisthesmallestatthetemperaturefrom850℃to930℃withheatingrateof15℃·min-1.Pyrolysiswasfurthercarriedoutonafixed-bedreactorwithdifferentheatingrate.Theproductionofhydrogenhasbeenstudiedinparticular.Itgavethehighesthydrogenproductionattheheatingrateof15℃·min-1.Anditalsofoundtheincreaseofhydrogenproductionwiththeraiseoftemperature.Furthermore,catalyticpyrolysisofcoalwasdoneatadding2%oftransition-metaloxidestodiscovertheimpactofcatalystsuponcoalpyrolysisatheatingrateof15℃·min-1.ItindicatedthatbothN-typeandP-typeoxideenhancedhydrogenproductionincoalpyrolysis.However,itshowedthatN-typeoxideincreasedhydrogenproductionatmediumtemperatures,andP-typeoxidesimprovedhydrogenproductionathighertemperatures.

简介：Intensiveturbulenceexistsinthewakesofhighspeedtrains,andtheaerodynamicperformanceofthetrailingcarcoulddeterioraterapidlyduetocomplicatedfeaturesofthevorticesinthewakezone.Asaresult,thesafetyandamenityofhighspeedtrainswouldfaceagreatchallenge.Thispaperconsidersmainlythemechanismofvortexformationandevolutioninthetrainflowfield.ArealCRH2modelisstudied,withaleadingcar,amiddlecarandatrailingcarincluded.Di?erentrunningspeedsandcrosswindconditionsareconsidered,andtheapproachesofunsteadyReynold-averagedNavier–Stokes(URANS)anddetachededdysimulation(DES)areutilized,respectively.ResultsrevealthatDEShasbettercapabilityofcapturingsmalleddiescomparedtoURANS.However,forlargeeddies,thee?ectsoftwoapproachesarealmostthesame.Inconditionswithoutcrosswinds,twolargevortexstreetsstretchfromthetrainnoseandinteractstronglywitheachotherinthewakezone.Withthereinforcementoftheground,acomplicatedwakevortexsystemgeneratesandbecomesstrengthenedastherunningspeedincreases.However,thelocationsofflowseparationsonthetrainsurfaceandtheseparationmechanismkeepunchanged.Inconditionswithcrosswinds,threelargevorticesdevelopalongtheleewardsideofthetrain,amongwhichtheweakestonehasnoobviousinfluenceonthewakeflowwhiletheothertwostretchtothetailofthetrainandcombinewiththehelicalvorticesinthetrainwake.Thus,optimizationoftheaerodynamicperformanceofthetrailingcarshouldbeaimingatreducingtheintensityofthewakevortexsystem.

简介：Evaporationofsessilewaterdropletonpolydimethylsiloxane(PDMS)surfaceswiththreedi?erentcuringratios(5:1,10:1,and20:1)wasexperimentallyinvestigatedinthispaper.Weshowthattheconstantcontactradius(CCR)evaporationonsurfacewithhighcuringratiolastslongerthanthatwithlowcuringratio.WealsomeasuredYoung’smoduliofPDMSfilmsbyusingatomicforcemicroscopy(AFM)andsimulatedsurfacedeformationofPDMSfilmsinducedbysessilewaterdroplet.WithincreasingcuringratioofPDMSfilm,Young’smodulusofPDMSfilmisgettinglower,andthentherewillbelargersurfacedeformationandmoreelasticstoredenergy.Sincesuchenergyactsasabarriertokeepthethree-phasecontactlinepinned,thusitwillresultinlongerCCRevaporationonPDMSsurfacewithhighercuringratio.

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简介：Structuraloptimizationforcrashworthinesscriteriaisofparticularsignificanceespeciallyatearlystageofdesign.ThecomparativestudyofKrigingandradialbasisfunctionnetwork(RBFN)wasperformedinordertoimprovethecrashworthinesseffectsofhoneycomb.ImprovingthecrashworthinesscharacteristicofhoneycombwasachievedusingLS-OPTanddomainreductionstrategy.Thisoptimizationisperformedonthebasisofvalidatednumericalsimulationtoestablishtheapproximatedmodeltoillustratetherelationshipbetweentheresponsesanddesignvariables.TheresultsshowedthatKrigingmeta-modelisexcelledinaccuracy,robustnessandefficiencycomparedtoradialbasisfunction(RBF)andcrashworthinesscharacteristicofhoneycombisimprovedby4%.

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简介：AseriesofCoMo/Al2O3catalystsforselectivehydrodesulfurization(HDS)ofgasolinewerestudiedwithRamanspectroscopy,apowerfulmethodthatcreatesspecifcsignalsforthestatesandthedistributionsofoxidicprecursorsandsulfdedactivephases.ThehighertheMoandCo,thelowerthetetrahedrallycoordinatedmolybdate,andthehigherthepolymolybdate.ButtheamountofpolymolybdatedecreasedwhenCoMoO4appeared.Cobalt-promotedpolymolybdatewastheprecursor,anditsrelativecontentcorrelatedwellwiththeHDSselectivity.Forsulfdedcatalysts,addingthecobalt-promoterledtolocaldistortion-disorderoftheMoS2structureandtheformationofaCoMoSphase.Thismethodcanprovideimportantinformationfordesigningnewindustrialselective-HDScatalysts.

简介：Selectivitycontrolisadifficultscientificandindustrialchallengeinmethanol-to-olefins(MTO)conversion.Ithasbeenexperimentallyestablishedthatthetopologyofzeolitecatalystsinfluencedthedistributionofproducts.Besidesthetopologyeffectonreactionkinetics,thetopologyinfluencesthediffusionofreactantsandproductsincatalystsaswell.Inthiswork,byusingCOMPASSforce-fieldmoleculardynamicsmethod,weinvestigatedtheintracrystallinediffusionofetheneandpropeneinfourdifferentzeolites,CHA,MFI,BEAandFAU,atdifferenttemperatures.Theself-diffusioncoefficientsanddiffusionactivationbarrierswerecalculated.AstrongrestrictiononthediffusionofpropeneinCHAwasobservedbecausetheself-diffusioncoefficientratioofethenetopropeneislargerthan18andthediffusionactivationbarrierofpropeneismorethan20kJ/molinCHA.Thisratiodecreaseswiththeincreaseoftemperatureinthefourinvestigatedzeolites.TheshapeselectivityonproductsfromdiffusionperspectivecanprovidesomeimplicationsontheunderstandingoftheselectivitydifferencebetweenHSAPO-34andHZSM-5catalystsfortheMTOconversion.

简介：Toimprovetheaerodynamicperformanceofsmallaxialflowfan,inthispaperthedesignofasmallaxialflowfanwithsplitterbladesisstudied.TheRNGk-εturbulencemodelandSIMPLEalgorithmwereappliedtothesteadysimulationcalculationoftheflowfield,anditsresultwasusedastheinitialfieldofthelargeeddysimulationtocalculatetheunsteadypressurefield.TheFW-Hnoisemodelwasadoptedtopredictaerodynamicnoiseinthesixmonitoringpoints.FastFouriertransformalgorithmwasappliedtoprocessthepressuresignal.Experimentofnoisetestingwasdonetofurtherinvestigatetheaerodynamicnoiseoffans.Andthentheresultsobtainedfromthenumericalsimulationandexperimentweredescribedandanalyzed.Theresultsshowthatthestaticcharacteristicsofsmallaxialfanwithsplitterbladesaresimilarwiththeprototypefan,andthestaticcharacteristicsareimprovedwithinacertainrangeofflux.Thepowerspectraldensityatthesixmonitoringpointsofsmallaxialflowfanwithsplitterbladeshavedecreasedtosomeextent.Theexperimentalresultsshowsoundpressurelevelofnewfanhasreducedinmostfrequencybandsbycomparingwithprototypefan.Theresearchresultswillprovideaproofforparameteroptimizationandnoisepredictionofsmallaxialflowfanswithhighperformance.

简介：Stent-graftimplantationisanimportantmeansofclinicaltreatmentforaorticdissectinganeurysm(ADA).However,researchesonfluiddynamicseffectsofstentwererare.ComputersimulationwasusedtoinvestigatetheinteractionsbetweenbloodstreamandvascularstructureinastentedADA,whichendurestheperiodicpulsevelocityandpressure.Weobtainedandanalyzedtheflowvelocitydistribution,thewalldisplacementandwallstressintheADA.Bycomparingthedifferentresultsbetweenanon-stentedandastentedADA,wefoundthattheinsertionofavasculargraftcanmakethelocationofmaximumstressanddisplacementmovefromtheaneurysmlumenwalltothearterywall,accompaniedwithagreatlydecreaseinvalue.Theseresultsimplythattheplacementofastent-graftofanykindtooc-cludeADAwillresultinadecreasedchanceofrupture.

简介：Manualacupunctureiswidelyusedforpainreliefandstresscontrol.Previousstudiesonacupuncturehaveshownitsmodulatoryeffectsonthefunctionalconnectivityassociatedwithoneorafewpreselectedbrainregions.Toinvestigatehowmanualacupuncturemodulatestheorganizationoffunctionalnetworksatawhole-brainlevel,weacupunctureatST36ofarightlegtoobtainelectroencephalograph(EEG)signals.Bycoherenceestimation,wedeterminethesynchronizationsbetweenallpairwisecombinationsofEEGchannelsinthreeacupuncturestates.Theresultingsynchronizationmatricesareconvertedintofunctionalnetworksbyapplyingathreshold,andtheclusteringcoefficientsandpathlengthsarecomputedasafunctionofthreshold.Theresultsshowthatacupuncturecanincreasefunctionalconnectionsandsynchronizationsbetweendifferentbrainareas.Forawiderangeofthresholds,theclusteringcoefficientduringacupunctureandpostacupunctureperiodishigherthanthatduringthepre-acupuncturecontrolperiod,whereasthecharacteristicpathlengthisshorter.Weprovidefurthersupportforthepresenceof'small-world'networkcharacteristicsinfunctionalnetworksbyusingacupuncture.Thesepreliminaryresultshighlightthebeneficialmodulationsoffunctionalconnectivitybymanualacupuncture,whichcouldcontributetotheunderstandingoftheeffectsofacupunctureontheentirebrain,aswellastheneurophysiologicalmechanismsunderlyingacupuncture.Moreover,theproposedmethodmaybeausefulapproachtothefurtherinvestigationofthecomplexityofpatternsofinterrelationsbetweenEEGchannels.

简介：Inthispaper,theeffectofaddingdifferentconcentrationsofkineticinhibitorsontheinductiontimeofhydrogensulfidehydrateformationinareactorequippedwithautomaticadjustabletemperaturecontrollerisstudied.Anovelmethodnamely"suddencooling"isusedforperformingtherelevantmeasurements,inwhichtheinductiontimeofH2Shydrateinthepresence/absenceofPVPandL-tyrosinewithdifferentconcentrations(100,500,and1000ppm)isdetermined.Asaresult,PVPwiththeconcentrationof1000ppminaqueoussolutionisdetectedasamoresuitablematerialforincreasingtheinductiontimeofH2Shydrateformationamongtheinvestigatedkinetichydrateinhibitors.

简介：Differentsystemshavebeenusedovertheyearstodeliverdrugparticlestothehumanskinforpharmaceuticaleffect.Researchhasbeendonetoimprovetheperformanceandflexibilityofthesesystems.Inrecentyearsauniquesystemcalledthetransdermaldrugdeliveryhasbeendeveloped.Transdermaldrugdeliveryopenedanewdoorinthefieldofdrugdeliveryasitismoreflexibleandoffersbetterperformancethantheconventionalsystems.Theprincipleofthissystemistoacceleratedrugparticleswithahighspeedgasflow.Amongdifferenttransdermaldrugdeliverysystemswewillconcentrateonthecontourshocktubesysteminthispaper.Acontouredshocktubeisconsistsofarupturechamber,ashocktubeandasupersonicnozzlesection.Thedrugparticlesareretainedbetweenasetofburstingdiaphragm.Whenthediaphragmisrupturedatacertainpressure,ahighspeedunsteadyflowisinitiatedthroughtheshocktubewhichacceleratestheparticles.Computationalfluiddynamicsisusedtosimulateandanalyzetheflowfield.TheDPM(discretephasemethod)isusedtomodeltheparticleflow.AsanunsteadyflowisinitiatedthoughtheshocktubethedragcorrelationproposedbyIgraetalisusedotherthanthestandarddragcorrelation.Theparticlevelocitiesatdifferentsectionsincludingthenozzleexitareinvestigatedunderdifferentoperatingconditions.Staticpressurehistoriesindifferentsectionsintheshocktubeareinvestigatedtoanalyzetheflowfield.Theimportantaspectsofthegasandparticledynamicsintheshocktubearediscussedandanalyzedindetails.

简介：Anewfiniteelementmethod(FEM)ofB-splinewaveletontheinterval(BSWI)isproposed.ThroughanalyzingthescalingfunctionsofBSWIinonedimension,thebasicformulafor2DFEMofBSWIisdeduced.The2DFEMof7nodesand10nodesareconstructedbasedonthebasicformula.Usingtheseproposedelements,themultiscalenumericalmodelforfoundationsubjectedtoharmonicperiodicload,thefoundationmodelexcitedbyexternalandinternaldynamicloadarestudied.Theresultsshowtheproposedfiniteelementshavehigherprecisionthanthetraditionalelementswith4nodes.Theproposedfiniteelementscandescribethepropagationofstresswaveswellwheneverthefoundationmodelexcitedbyexternalorinternaldynamicload.Theproposedfiniteelementscanbealsousedtoconnectthemulti-scaleelements.Andtheproposedfiniteelementsalsohavehighprecisiontomakemulti-scaleanalysisforstructure.

简介：Electron-wallinteractionisalwaysrecognizedasanimportantphysicalproblembecauseofitsremarkableinfluencesonthrusterdischargeandperformance.Basedonexistingtheories,anelectrodeispredictedtoweakenelectron-wallinteractionduetoitslowsecondaryelectronemissioncharacteristic.Inthispaper,theelectron-wallinteractioninanAton-typeHallthrusterwithlow-emissiveelectrodesplacedneartheexitofdischargechannelisstudiedbyafullykineticparticle-incellmethod.Theresultsshowthattheelectron-wallinteractionintheregionofsegmentedelectrodeisindeedweakened,butitissignificantlyenhancedintheremainingregionofdischargechannel.Itismainlycausedbyelectrodeconductivepropertywhichmakesequipotentiallinesconvextowardchannelexitandevenparalleltowallsurfaceinnear-wallregion;thisconvexequipotentialconfigurationresultsinsignificantphysicaleffectssuchasrepellingelectrons,whichcausestheelectronstomovetowardthechannelcenter,andtheelectronsemittedfromelectrodestoberemarkablyaccelerated,therebyincreasingelectrontemperatureinthedischargechannel,etc.Furthermore,theresultsalsoindicatethatthedischargecurrentinthesegmentedelectrodecaseislargerthaninthenon-segmentedelectrodecase,whichisqualitativelyinaccordancewithpreviousexperimentalresults.