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简介：WetheoreticallyinvestigatednegativeentropySofbiopolymerwhichpassesthroughananometerpore(suchasα-hemolysin),especiallyenteringprocessandescapingprocess,onthebasisofwhichwealsostudiedbiopolymerentering-poretimeτent,biopolymerenteringmeanvelocityvent,biopolymerescaping-poretimeτesc,andbiopolymerescapingmeanvelocityvesc,respectively.Ourresultsillustratethattheenteringandescapingprocessesofbiopolymerdependonitsnegativeentropy,andenteringprocessismoredifficultthanescapingprocessforbiopolymertranslocation.Thistremendousdifferencebetweenthetwoprocesseswillofferausefulengineeringhintforsinglemacromoleculeidentification.

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简介：Thispaperproposesanautomaticmethodofporecombinationrecognition,whichisanimportantfeaturetohardwoodrecognition.Afterextractingedgefromwoodmicroscopiccross-section,basedonareahistogramofthesimilarcircleregions,themethodclassifiesallregionsintotwoclasseswithmaximumbetween-classvariance,soastodistinguishtheporefromothertextures,whicharesimilarinshapesbutdifferentinsizes.Meanwhile,secondobjectivefunctionaboutaverageareaofclosedregionsisusedtoimprovetheporesegmentationperformance.Atlast,themethodusesadjacencydegreeofporesettojudgeporecombination.Theexperimentsdemonstratethatthetaskofporesegmentationcanbecompletedsuccessfullyforallkindsofporedistributionandcombination,andalsothecorrectcombinationsofporesaregiven.

简介：DuringthereactionbetweencalciumsorbentsandSO2,calciumsorbentsarefirstcalcinedandconvertedintoCaO.CaOcanbeobtainedbycalciningCa(OH)2orCaCO3.Theporosityofthesorbentisincreasedbecauseofcalcinationandisdecreasedbecauseofsulfurization.InthecalcinationprocessH2OorCO2isescapedfromtheparticlesandporesareformedinparticles.ThereactionorconvertrateofCaOisinfluencedstronglybytheporestructurecharacters.FromCa(OH)2toCaOtheescapevelocityofH2Ooritsmasstransferisoneofthekeyfactorsinfluencingtheporeforming.Duringcalcinationprocessdifferentheatingvelocity,differentheatingtimeandtemperatureweresuggested.Thetemperaturerisingrateandcalciningtemperatureplayimportantroletotheporestructure.TheconvertratesofCaOobtainedthroughdifferentcalciningconditionswereinvestigatedexperimentally.SomeinterestingresultswereshowedthatthecalciumutilizationofCaOparticlesisdeterminednotonlybythespecialsurfaceareaandtotalporevolume,butalsobypore-sizedistribution.Themainfactorinfluencingthesulfationistheporediameterdistributionatlowersulfationtemperature.Forhigherreactiontemperaturespecificvolumeistheimportantreason.Butpore-sizedistributionisstronglyinfluencedbyheatfluxandtemperatureinthecalciningprocess.

简介：ChloridecontentandthepHvalueoftheporesolutionintheneighborhoodofsteelreinforcementaredecisiveparametersforinitiationandrateofcorrosion.Theporesolutionofcementmortarandhardenedcementpastehasbeenexpressedfromtheporespacebyhighpressureintheinvestigation.Theinfluenceofthewater-cementratio,age,andadditionofchloridetothefreshmixonchloridecontentintheporesolutionhasbeendeterminedbyionchromatography.AtthesametimethepHvalueoftheporesolutionhasbeendetermined.Thedissolvedchloridecontentdecreaseswithincreaseinthewater-cementratio.Theamountofboundchlorideincreaseswithtime,butitdecreaseswithdecreasingcontentofdissolvedchlorideintheporesolution.Asignificantinfluenceofcarbonationonthedissolvedchloridecontentoftheporesolutionhasbeenobserved.Withcompletecarbonation,thedissolvedchloridecontentincementmortarandhardenedcementpasteincreasesbyafactorbetween2and12.Theboundchloridedecreasesby27%-4%.Asexpected,thepHvaluedecreasesfromaround13.2toaslowas8.0duetocarbonation.ItcanbeconcludedthatcarbonationnotonlylowersthepHvaluebutliberatesboundchloride.Thisisoneobviousreasonwhythecombinedactionofchloridepenetrationandcarbonationacceleratessteelcorrosionandshortenstheservicelifeofreinforcedconcretestructures.

简介：有0.2–的直径的新宏观规模的SBA-15范围；0.5公里被sol–准备；胶化方法，tetrabutylorthosilicate(TBOS)在被用作硅来源和triblock共聚物和polyoxyethylene辛基酚醚(OP-10)(P123)被用作模板。结果球形的样品被XRD描绘，N2adsorption–；解吸附作用，TEM和SEM方法。结果证明SBA-15宏范围的内部结构有宏多孔的隧道(0.5μ；m)并且我酣睡的骨骼(4–；5nm)。有层次毛孔结构的这些SBA-15宏范围为Emodin分子表明高吸收能力。

简介：Adensityfunctionaltheoryisappliedtocalculatingthelocaldensityprofilesofcolloidsconfinedinaslit-likeporeaswellastheradialdistributionfunctionsofbulkcolloids.Theinteractionbetweenthecolloidalparticlesisdescribedusingahard-coreYukawamodel.TheexcessHelmholtzenergyfunctionalisacombinationofthemodifiedfundamentalmeasuretheoryofYuandWu(2002)forthehard-corecontributionandacorrectedmean-fieldtheoryfortheattractivecontribution.ComparisonwiththeresultsfromtheMonteCarlosimulationsshowsthatthecorrectedtheoryimprovesthedensityprofilesofcolloidsinthevicinityofcontactovertheoriginalmean-fieldtheory.Boththepresentcorrectedtheoryandsimulationssuggestthattherearedepletionanddesorptionforthecolloidwithstrongattractionbetweenparticlesatlowtemperature.

简介：Ｉｎｍｉｄｓｕｍｍｅｒ，ｔｈｅＣｈｉｎｅｓｅＡｓｓｏｃｉａｔｉｏｎｆｏｒＩｎｔｅｒｎａｔｉｏｎａｌＵｎｄｅｒｓｔａｎｄｉｎｇ（ＣＡＦＩＵ）ｗｅｌｃｏｍｅｄｔｈｅｆｉｒｓｔｇｒｏｕｐｏｆＪｏｒｄａｎｇｕｅｓｔｓ．ＡｔｔｈｅｉｎｖｉｔａｔｉｏｎｏｆＣＡＦ...

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简介：Byutilizinghardtemplatemethodtoadjustthemesoporelength,andalkaliactivationtogeneratemicropores,twohierarchicalporouscarbons(HPCs)wereprepared.Withcontrollingoftheirmesoporelengthandtheactivationconditions,thecomplexsystemcomposedbyHPCsandelectrolytewassimplifiedandtheeffectofmesoporelengthontheperformanceofHPCsaselectrodesinsupercapacitorswasinvestigated.Itisfoundthatwiththemesoporelengthgettingsmaller,theorderedareagetssmallerandthaggregationoccurs,whichiscausedbythehighsurfaceenergyofsmallgrains.HPCwithlongpore(HPCL)exhibitsadonut-likemorphologywithwell-definedorderedmesoporesandaregularorientationwhileinHPCwithshortpores(HPCS),shortmesoporesareonlyorderlydistributedinsmallregionsLongerorderedchannelsformunobstructedwaysforionstransportintheparticleswhileshorterchannels,onlyorderlydistributedinsmallareas,resultsinblockedpaths,whichmayhindertheelectrolytionstransport.Duetotheunobstructedstructure,HPCLexhibitsgoodratecapabilitywithacapacitancretentionrateover86%ascurrentdensityincreasingfrom50mA/gto1000mA/g.ThespecificcapacitanceofHPCLderivedfromthecyclicvoltammetrytestat10mV/sisupto201.72F/g,whilethespecificapacitanceofHPCSisonly193.65F/g.

简介：Theactivatedaluminaasacatalystcarrierwerewidelyusedinautomotiveexhaustcatalystsunderhightemperature,suchas,petroleumrefiningcatalysts,hydrogenationandhydrodesulfurizationcatalystcarrierinChinaandabroad.γ-Al2O3wasthecatalystcarrierthatwasthemostwidelyusedandthebestcarrierofimprovedspecificsurfacearea.However,theactivationofthecoatingconsistedofγ-Al2O3wereusuallytransformedintoα-Al2O3at800oC,causingincreaseddensity,reducedspecificsurfacearea,andthecollapseresultofporestructure.Whilethetemperaturereached1200oC,activationofcoatingdetachedfromthecarrier,theresistanceofflowinggasincreased,catalyticactivitydecreased.AdditionofLa2O3stabilizedtheγ-Al2O3crystalstructure,whichwouldkeeptheactivationstabilityofcoatingatahightemperatureandinhibitactivityloss.Theactivatedaluminacarriertreatedwiththesolid-pore-expandingagentcontaining[La(EDTA)]-thatsynthesizedusingsolidandsolid-hybridapproachwiththethermalstabilizerlanthanaandEDTAatthehigh-temperaturehada10-30μmlargeporeporousnetwork-likestructure,afteraluminawascalcinedat1200oCfor1h.Thespecificsurfaceareaoffourspecimenwerebeyond120m2/g,whilethesamplespecificsurfaceareaofx([La(EDTA)]-)=1%wasupto150.36m2/g.

简介：Aseriesofregularwaveexperimentshavebeendoneinalarge-scalewaveflumetoinvestigatethewave-inducedporepressurearoundthesubmarineshallowlyembeddedpipelines.Themodelpipelinesareburiedinthreekindsofsoils,includinggravel,sandandsiltwithdifferentburialdepth.Theinputwaveschangewithheightandperiod.Theresultsshowthattheamplitudesofwave-inducedporepressureincreaseasthewaveperiodincrease,anddecayfromthesurfacetothebottomofseabed.Higherporepressuresarerecordedatthepipelinetopandthelowerporepressuresatthebottom,especiallyinthesandseabed.Thenormalizedpressurearoundpipelinedecreasesastherelativewaterdepth,burialdepthorscatteringparametersincrease.Forthesiltseabed,thewavelettransformhasbeensuccessfullyusedtoanalyzethesignalsofwave-inducedporepressure,andtheoscillatoryandresidualporepressurecanbeextractedbywaveletanalysis.Higheroscillatorypressuresarerecordedatthebottomandthelowerpressuresatthetopofthepipeline.However,higherresidualpressuresarerecordedatthetopandthelowerpressuresatthebottomofthepipeline.

简介：Porestructurecharacteristicsofrockareagreatconcernforresearchersandpractitionersinrockmechanicsandrockengineeringfields.Inthisstudy,mercuryintrusionporosimetry（MIP）wasusedtomeasureporesizedistribution,aswellasseveralimportantindexparametersofporestructure,forsevencommontypesofdeepsedimentaryrockswithatotaloffiftyrocksamples.Resultsshowasimilarporesizedistributionpatternoftherocksamplesinthesamelithologicalgroup,butremarkabledifferencesamongdifferentlithologicalgroups.Amongseveninvestigatedrocktypes,mudstonehasthesmallestporosityof3.37%,whileconglomeratehasthelargestvalueof18.8%.Itisalsofoundthattheporosityofrocktypeswithfinergrainsizeislowerthanthosewithcoarsergrainsize.Meanwhile,acomparisonoffrequencydistributionattenintervalsofpore-throatdiameteramongseventypesofsedimentaryrocksrevealsthatdifferentrocktypeshavedifferentdominantpore-sizeranges.Furthermore,permeabilityoftheinvestigatedsedimentaryrocksampleswasderivedbasedonMIPdatausingreportedtheoreticalequations.Amongsevenrocktypes,mudstonehasthelowestaveragedpermeability(3.64×10-6mD)whileconglomeratehasthehighestone(8.59×10-4mD).Frommudstonetoconglomerate,rockpermeabilityincreaseswithanincreaseofgrainsize,withonlyanexceptionofsiltstonewhichhasarelativelylargerporosityvalue.Finally,regressionanalysisshowthatthereisagoodfitting（R2=0.95）betweenpermeabilityandporositywhichcouldbeeasilyusedtoderivereliablepermeabilityvaluesofsimilarkindsofengineeringrocks.

简介：Aseriesofsisalbasedactivatedcarbonfiberswerepreparedwithsteamactivationattemperaturefrom750℃to900℃.Theirporestructureswerecharacterizedthroughtheirnitrogenadsorptionisothermsat77Kusingdifferenttheories.Theresultsshowedthatt-plotmethodandDR-plotmethodcouldsuitablybeusedtocharacterizethemesoporestructureandthemulti-stagedistributionofporesizeofactivatedcarbonfibers.Italsoshowedthattheporesizewidenswiththeincreaseofactivationtemperature.

简介：Ｐｏｒｅｐｒｅｓｕｒｅｉｎｄｅｐｂｏｒｅｈｏｌｅｓ：ＩｔｓｍｅａｓｕｒｅｍｅｎｔａｎｄｒｅｌａｔｉｏｎｗｉｔｈｓｅｉｓｍｉｃａｃｔｉｖｉｔｉｅｓＪＩＡＮＬＩＧＡＯ（高建理）ＳＨＩＺＯＮＧＳＵＮ（孙世宗）ＪＩＡＮＭＩＮＤＩＮＧ（丁健民）ＧＵ...

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简介：ThemolecularsieveVPI-5wassynthesizedbyusingvariousorganicamines(DEA,Di-PA,DBA,DPenA,TBA,DEOAandTEOA)asthestructure-directingagent.TheuseofDPAenlargedtherangeofthecrystallizationtemperaturefrom110℃to190℃inthesynthesisofVPI-5,whiletheuseofTEOAchangedthecompositionofthereactantsinabroadvariety.DiaminesarethetypicalaminesinthesynthesisofVPI-5.AmongthemDBAandDPAarethemostfavoritestructure-directingagentsforthesynthesisofVPI-5molecularsieve.

简介：Centrifugeexperimentsarecarriedouttoinvestigatetheresponsesofsuctionbucketfoundationsunderhorizontaldynamicloading.Theeffectsofloadingamplitude,thesizeofthebucketandthestructuralweightonthedynamicresponsesareinvestigated.Itisshownthat,whentheloadingamplitudeisoveracriticalvalue,thesandattheupperpartaroundthebucketsoftensorevenliquefies.Theliquefactionindex(excessporepressuredividedbyinitialeffectivestress.Inthispaper,thedevelopmentaldegreeofexcessporepressureisdescribedbyliquefactionindex)decreasesfromtheupperparttothelowerpartofthesandfoundationintheverticaldirectionanddecreasesfromneartofarawayfromthebucket′ssidewallinthehorizontaldirection.Largesettlementsofthebucketandthesandaroundthebucketareinducedbythehorizontaldynamicloading.Thedynamicresponsesofthebucketofasmallerheight(whenthediameteristhesame)areheavier.Acycliccracksomedistancenearthebucketoccursinthesand.

简介：Anumericalmethodisproposedfortheelasto-plasticityandpore-pressurecoupledanalysisonthepulloutbehaviorsofaplateanchor.Thebounding-surfaceplasticity(BSP)modelcombinedwithBiot’sconsolidationtheoryisemployedtosimulatethecyclicloadinginducedelasto-plasticdeformationofthesoilskeletonandtheaccompanyinggeneration/dissipationoftheexcessporewaterpressure.Thesuctionforcegeneratedaroundtheanchorduetothecyclicvariationoftheporewaterpressurehasmucheffectonthepulloutcapacityoftheplateanchor.Thecalculatedpulloutcapacitywiththeproposedmethod(i.e.,thecoupledanalysis)getslowerthanthatwiththeconventionaltotalstressanalysisforthecaseoflong-termsustainedloading,butslightlyhigherforthecaseofshort-termmonotonicloading.Thecyclicloadinginducedaccumulationofporewaterpressuremayresultinanobviousdecreaseofthestiffnessofthesoil-plateanchorsystem.