简介:Sprayauto-ignitionexperimentswerecarriedoutinaconstantvolumecombustionchamberforsomepurealkanes(n-paraffinswithdifferentchainlength,cyclohexane,n-butylcyclohexane,andisooctane)andblendsofn-decanewithStandardBlendedFuel(isooctane/n-heptane)andproductgasoline.Testresultsshowedthatthereactionactivityofn-paraffinswasrelativelyhigh.Meanwhile,theauto-ignitioncharacteristicsdifferedsignificantlywiththemolecularstructuresofalkanes.Addingdifferentvolumefractionsofn-decanetoStandardBlendedFuelandproductgasolinecouldimprovethefuelreactionactivityatvaryingdegree.Finally,functionalgroupseffectswereusedtosimulatetherelationshipbetweenthemoleculartopologyandtheauto-ignitionquality.
简介:Throughimprovingtheagingprocessduringsynthesisofthesupport,γ-Al2O3withlargeporevolumeandhighsurfaceareawassynthesizedbyafacilesecondaryreformingmethod.Thesynthesisparameters,suchasthereactiontemperature,thefirstagingtemperatureandthesecondagingtemperature,wereinvestigated.Thetexturalpropertiesofγ-Al2O3werecharacterizedbymeansofN2adsorption-desorptionisotherms,X-raypowderdiffractometry(XRD),scanningelectronmicroscopy(SEM),Fouriertransforminfrared(FTIR)spectroscopyandthermogravimetry(TG).TheexperimentalresultsindicatedthatAACHandamorphousAlOOHweretheprecursorsofalumina,whichwereformedviaprecipitationfromsolutionsafterreactionofaluminumsulphatewithammoniumhydrogencarbonate.Theprecursornanocrystallitesgrewandre-assembledduringthesecondaryreformingprocess,whichresultedinanincreasedporesizeandporevolumeandadecreasedbulkdensity.Theas-synthesizedγ-Al2O3materialsfeaturedmeso/macroporosity,largeporevolume(2.175cm3/g),highsurfacearea(237.8m2/g),andlowbulkdensity(0.284g/mL).