简介：Debrisflowsinnaturegenerallyfallintothreegroupsdistinctintheirgraincomposition:water-stoneflow,orsub-viscousdebrisflow,dominatedbycoarsegrains;muddyflow,dominatedbyfinegrains;andviscousdebrisflowcomposedofgrainsinlargerange.Liquid-phasevelocityandsedimentarydeliveryresistanceofsub-viscousdebrisflowhavebeendiscussedbasedonthecompositioncharactersofsub-andhigh-viscousdebrisflows.Itisrevealedthatthepresenceoffinegrainsplaysavitalroleinaffectingresistanceandaveragevelocity,particularlywhenthevolumefractionofgrainsintheflowisrelativelyhigh,i.e.Sv＞0.45.Grain-sizedistributionofviscousdebrisflowischaracterizedbyabimodalcurve,whichexplainsthepropertieslikehighdensityandlowresistancegradientofdebrisflows.Acalculationformulaisfinallyputforward,whichhastosomeextentovercomelocalitylimitsandachievedagoodagreementwiththefieldobservationsofdebrisflowsinSouthwestChina.

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简介：AnonlinearBurgers’modelisusedtodescribeverticalinfiltrationofwaterintoanon--swellingsoilwithprescribedconcentrationconditionsattheboundary.Theexactsolutionisconstructedintermsofaseriesinvolvingcomplementaryerrorintegrals.

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简介：Insteady,solid-liquidtwo-phaseturbulentflows,thereexisttwotypicalpatternsoftheverticaldistributionofparticleconcentration.ThepatternIshowsamaximumconcentrationatanelevationabovethebed.ThepatternIIshowsanincreaseoftheparticleconcentrationdownwardoverthewholevertical,withthemaximumatthebed.MostofthetheoriesonparticleconcentrationdistributionhavebeendonewiththepatternII,anditislackofasuccessfultheorycovetingbothofthetwopatterns.Thispaperreviewstheparticledistributiontheories,includingthediffusiontheory,themixturetheory,theenergytheory,thesimilaritytheory,thestochastictheoryandthekinetictheory.Thekinetictheoryisalsoappliedtodescribetheverticaldistributionofparticleconcentrationinbothdiluteanddenseflows.

简介：Thepaperpresentsexperimentalstudyofdebrisflows.Theequilibriumconcentrationofsolidparticleintheflowisafunctionoftheenergyslope,densityofsolidparticleandkineticfrictionangleofparticles.Thekineticfrictionangleisafunctionofinternalfrictionangle,theconcentrationofsolidparticlesandthemaximumpossibleconcentration.Todeterminethefunctionbetweenthekineticfrictionangleandinternalfrictionangleistheaimofthisresearch.Flumeexperimentsofequilibriumconcentrationaboutparticlesinwaterandslurrywereconducted.Thelargedensityslurrymadethecoarseparticlesbeabletomoveinsmallslope.Thefunctionbetweenthekineticfrictionangleandinternalfrictionanglewasfoundfromtheseexperiments.Thecoarseparticlesandfineparticlesarewellmixed.D50demarcationlinewassuggestedinthispapertodemarcatethecoarseparticleandfineparticleofdebrisflows.TheequilibriumconcentrationofdebrisflowswascalculatedbyusingDs0demarcationforthedebrisflowsinfield.Theequilibriumconcentrationofdebrisflowscalculatedbythefunctionbetweenthekineticfrictionangleandinternalfrictionanglewasclosetotheequilibriumconcentrationdataofdebrisflowsinfield.

简介：Thepresentpaperisfocussedontheeffectsofviscousandturbulentshearstressesonbothverticalvelocityandconcentrationdistributionsinlargesuspensionofsands.Whentheflowcarrieslargeamountofsedimentsinsuspension,thepropertiesoffluidmixturearechangedintermsofmodifiedviscosity,densityandfallvelocity,andhencetheflowcharacteristics.Theoreticalmodelshavebeendevelopedforbothvelocityandconcentrationprofiles,takingintoaccounttheviscousandturbulentshearstresses,whicharethefunctionofvolumetricconcentration.Comparisonoftheoreticalmodelswithexperimentaldatarevealsthat(i)themodifiedvelocityandconcentrationprofilesagreewellwiththeobserveddataforhighsuspension,(ii)thehigherthesedimentsuspension,thesmallerthevonKarmanconstant,and(iii)sedimentdiffusioncoefficientislessthanmomentumdiffusioncoefficientforfinesandsinsuspension.

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简介：Anovelfluorometerbasedonfiberopticsisbrieflyintroducedforthemeasurementofalgaconcentration.Boththeexcitinglightandthefluorescencefromalgachlorophyllaretransmittedalongafibercable.Bythisway,wecangetalgaconcentrationbymeasuringitschlorophyll-afluorescenceintensity.Theexperimentresultsshowthatthisinstrumentischaracterizedbygoodsensitivity,linearityandaccuracy.

简介：ForareasonableclassofweakPoincaréinequalities,thedecayofthecorrespondingMarkovsemigroupsobtainedearlierbyRcknerandthefirstnamedauthorisimprovedbyremovinganextraL~2-norm.Next,aconcentrationestimateofthereferencemeasureispresentedfortheweakPoincaréinequality,whichissharpasillustratedbysomeexamplesofone-dimensionaldiffusionprocesses.

简介：Combinedwithflow-injection(Fl)technology,asimplechemiluminescence(CL)methodwasdevelopedforhydrazinedeterminationinthispaper.ItwasfoundthathydrazinecouldgreatlydecreasethestrongCLsignalproducedbythereactionbetweenluminolandhexacyanoferrate(Ⅲ)inalkalinemedium.ThedecreasedCLintensitywaslinearwithhydrazineconcentrationintherangeof5.0×10-9gmL-1to4.0×10-5gmL1,andthelimitofdetectionwas2.0×10-9gmL-1(3σ)witharelativestandarddeviationof2.4～4.1%(n=5).

简介：Theabsorptionoffreealkaliatlowconcentrationbysubacidresinwastracedwithelectricconductancemethod,theeffectoftemperatureontheadsorption,theactivationenergy,ofadsorption(Ea)andinteractionenergy(U)wasstudied.Theresultshowedthat,theprocessoflowconcentrationalkaliadsorptionbysubacidresinwasinaccordancewithmechanismofmonomolecularlayerabsorption,inaddition)withtheincreasingoftemperature,theinteractionenergybetweenadsorbateandsorbentincrease,sodidthesurfaceadsorptionrate(k),andlinearcorrelationexistedbetweeninteractionenergy(U)andtemperature(T).

简介：在低CTAB集中的血红素(Hb)的性质上的cetyltrimethylammonium溴化物(CTAB)的效果被紫外力的光谱，荧光，希腊语的第六个字母潜力，电导率和否定染色的传播电子显微镜(TEM)的方法在Hb/acyclovir/CTAB系统学习。随CTAB集中，在276nm的紫外山峰紧张，内在的荧光，Hb的希腊语的第六个字母潜力和系统的增加，电导率都被提高。Hb容易被氧化到oxyHb和hemichrome。在Hb/acyclovir/CTAB，Hb的系统，成为紫外力的光谱的CTAB，荧光，电导率和符合构造趋于原来的Hb被还给那些但是不那么做的希腊语的第六个字母潜力。Hb-acyclovir建筑群的紫外吸收山峰消失了，并且acyclovir引起的Hb的紧密的结构是refolded。当CTAB集中比5高时；

简介：ＭｅａｓｕｒｅｍｅｎｔｏｆＣｏｎｃｅｎｔｒａｔｉｏｎＤｉｓｔｒｉｂｕｔｉｏｎｏｆ　ＥｌｅｃｔｒｏｇｅｎｅｒａｔｅｄＥｔｃｈａｎｔＵｓｉｎｇａｎＥｌｅｃｔｒｏｃｈｅｍｉｃａｌＰｒｏｂｅＴｅｃｈｎｉｑｕｅＭｅａｓｕｒｅｍｅｎｔｏｆＣｏｎｃｅｎｔｒａｔｉｏ...

简介：Thechlorophyll-aconcentrationisgenerallyoverestimatedforthesouthemChinacoastalwatersifthedefaultalgorithmoftheSeaDASisemployed.Analgorithmisdevelopedforretrievalofchlorophyll-aconcentrationintheZhujiangEstuary,GuangdongProvince,China,byusingsimulatedreflectancedata.ThesimulatedreflectanceiscalculatedcorrespondingtotheSeaWiFSwavelengthbands,viaageneralmodelbyinputtingmeasuredwatercomponents,I.e.,thesuspendedsediment,chlorophyll-a,andyellowsubstance(DOC)concentrationdataof130samples.Empiricalrelationshipsofthechlorophyll-aconcentrationto240differentbandcombinationsareinvestigatedbasedonthesimulatedreflectancedata,andthebandcombination,R5R6/R3R4,isfoundtobetheoptimumoneforthedevelopmentofanalgorithmvalidfortheZhujiangEstuary.Thisalgorithmisthenemployedtodeterminethechlorophyll-aconcentrationfromSeaWiFSdata.TheestimatedconcentrationshaveabetteraccuracythanthoseobtainedfromtheSeaDASdefaultalgorithmwhencomnparedwithseatruthdata.Thenewalgorithmisdemonstratedtoworkwellandisusedtoderiveaseriesofimagemapsofthechlorophyll-aconcentrationdistributionfortheZhujiangEstuaryandadjacentcoastalareas.

简介：TheclucidationofconditionsoffVrmationofthelarge-scalemineraldepositsattractsattentionofanumberofresearchersdealingwiththedepositsofvariousgeneticgroupsformedinvariousgcodynamicenvironments’Suchsupcrlargedcpositsarewellknownamongthewidelysprcadgroupofhydrotber-maldepositsassociatcdwiththcstructurcsof

简介：CalculationsbasedontheavailablethermodynamicdataofAuCl2^-andAu(HS)2^-indicatethatAuCl2^-isresponsibleforthetransportandenrichmentofgoldduringthestageofpre-concentrationinthesourcebedwhileAu(HS)2^-isthemaingoldspeciesinvolvedintheformationofgolddepositsinresponsetohydrothermalreworking.Acidchloridesolutionswithαcl^->10°andsulfur-richsolutionswitha∑sinexcessof10^-2areheldasimportantcriteriaforgoldenrichmentinthesourcebedandfortheformationofgolddepositsbysubsequenthydrothermalevent,respectively.

简介：Theconcentrationsofnitrousoxidevariesbetween57and329nmol/dm3,saturationis674%～4134%intheZhujiangRiverEstuary.Thissuggeststhattheareaisanemissivesourceofnitrousoxide.Theacetyleneinhibitiontechniqueisemployedtoevaluatetheratesofnitrification,denitrificationandnitratereductionbybacterialactivitiesinthesedimentsatthreesites.Theaverageofnitrification,ticalprofilesofthesedimentsshowthatthenitrificationanddenitrificationprocessesmainlytakeplaceinthedepthfrom0to4cmanddependonregionalconditions.Theratesofnitrification,denitrificationandnitratereductionaredominatedbyEh,nitrateandammoniumconcentrationsinsedimentsandDOinoverlaywater.Thereisacouplingbetweennitrificationanddenitrification.