简介：Whenusingtherandomprocessinsoilprofilemodeling,thestationaryandergodicityofthesoilpropertiesintheprofilemustbetested.Thispaperdescribesaprocedureforstationaryandergodicitytesting.Numericalexamplesweregivenfordemonstration.Alog-cosinefunctionissuggestedtosimulatethecorrelationfunction,whichhasbeenprovedtobegoodforsoilprofilemodeling.

简介：Thesimulationofthewholeship-bridgecollisionprocesscanbeeffectivelycarriedoutbynonlineardynamicfiniteelementmethod.Basedonthesimpledescriptionofthetheory,ascenarioofa40000DWToiltankercollidingwithabridgeacrosstheYangtzeRiverisdesignedforsimulation.Thetechnologyofstructuremodelingandthedeterminationofrelatedparametersareintroduced.Thedeformationofthebulbbow,thehistoryofcollisionforcechange,theexchangeofcollisionenergyandthestressdistributionofthebridgepieraredescribedindetail,whichareofgreatvaluetobridgede-signandbridgepierdamageestimation,Somemechanicalcharactersintheprocessofship-bridgecollisionaredescribed.Moreaccurateresultscanbeproducedbyfiniteelementmethodthanthatbyempiricalformulasandsimplifiedanalyticalmethods.

简介：为WTP的产品水的混浊标准根据在中国的南部的区域的饮料水的保护措施技术上的州的工程‘863'是0.1NTU。在激活的碳过滤器的混浊移动在飞行员规模测试被分析；在生物学上激活的碳(用绳子拖的平底渡船)改进混浊移动的一种创新技术过滤被提出以便满足标准。试验性的结果证明由增加polymerized铝氯化物(PAC)进BAC过滤器的提高的过滤在混浊控制是相当有效的。自河混浊在0.05mgL与PAC的增加为0.1100240NTU的流入的混浊与大约80%的高移动在0.033NTU的稳定的水平(平均数)被保留[1]，完全为等于的filtrate混浊或不到0.1NTUC满足要求。另外，PAC剂量越大，越多降低自河混浊。然而，混浊移动的进一步的改进不为在0.l0mgL以外的PAC剂量是明显的，；在0.050.10mgL的范围的最佳的PAC剂量被建议。

简介：TheChangjiangRiverDeltaisadeltaoftremendousscalewhichisformedunderthecontroloftideandtidalcurrents.ThestudyontheroleoftideandtidalcurrentsintheprocessofformationanddevelopmentoftheChangjiangRiverDeltacanprovideatypicalexamplefortheocean-continentinteractionprocessintheeastareaofourcountry.ThetideandtidalcurrentsintheBohaiSea,YellowSeaandEastChinaSeaatthepost-glacialtransgressionmaximumaresimulated,thesedimenttransportfieldinthePaleo-ChangjiangRiverEstuary(PCRE)anditsperipheralareaatthattimeiscalculated,andtheseabederosion/accretionpatternisobtainedaccordingtothedivergenceofsedimenttransportrate.Theresultsshowthatadistinctivewavebellyofstandingtidalwaveexistedatthepost-glacialtransgressionmaximumandthewavebellylinesprotrudedseawardsfromthewavebellypointinthemouthofthePCRE.Underthewavebellycontroltidalcurrentsconvergetoordivergefromthewavebell

简介：UsingtheSASsoftware,thedataofenvironmentalfactorsvs.redtidebiomasswereanalysedduringtheprocessofSkeletonemacostatumredtidewhichbrokeoutintheChangjiangEstuaryonJune9～15,1990.Theresultsofthemultivariatestatisticalanalysisshowthattheenvironmentalfactorsaresimilarintheirdevelopingandmaintenanceperiodsandthatthevaluesofenvironmentalfactorsbegintoberestoredtonormallevelsduringthedisappearingperiod.Theresultsobtainedfromusingthemethodsofcorrelation,variableclusterandmaincomponentanalysesarebasicallyidentical.Theimportantfactorscontributingtotheoccurrenceofthisredtideareatmosphericalpressure,watertemperature,salinity,pH,No3-,-N,Po43--PandFe,amongwhich,salinity,FeandPO43--Paretheleadingfactorswhichhavetriggeredtheoccurrenceoftheredtideasdeterminedbythestep-by-stepregressionanalysis.Meanwhile,thelineardiscriminationfunctionshavebeenestablishedfortheredtide.TheenvironmentalfactordataofanotheroccurringprocessofSkeletonemacostatumredtideintheChangjiangEstuaryhavebeenchosenforredtidediscriminationwithsatisfactoryresults.

简介：Inordertostudybucklingpropagationmechanismindeepseapipelines,thecontactbetweenpipeline’sinnerwallsinbucklingprocesswasstudied.Atwo-dimensionalringmodelwasusedtorepresentthepipelineandanonlinearspringmodelwasadoptedtosimulatethecontactbetweeninnerwalls.Basedontheelastoplasticconstitutiverelationshipandtheprincipleofvirtualworktheory,thecouplingeffectofpipeline’snonlinearlargedeformationandwallcontactwasincludedinthetheoreticalanalysiswiththeaidofMATLAB,andtheapplicationscopeofthetheoreticalmodelwasalsodiscussed.Thecalculatedresultsshowthatduringtheloadingprocess,thechangeinexternalpressureiscloselyrelatedtothedistributionofsectionstress,andoncethewallsarecontactingeachother,theexternalpressureincreasesandthenremainsstableafteritreachesaspecificvalue.Withoutfracture,thepipelinesectionwillstopshowingdeformation.Theresultsoftheoreticalcalculationsagreewellwiththoseofnumericalsimulations.Finally,inordertoensurereliabilityandaccuracyofthetheoreticalresults,thecollapsepressureandpropagationpressurewerebothverifiedbynumericalsimulationsandexperiments.Therefore,thetheoreticalmodelcanbeusedtoanalyzepipeline’sbucklingdeformationandcontactbetweenpipeline’sinnerwalls,whichformsthebasisforfurtherresearchonthree-dimensionalbucklingpropagation.

简介：为有机化合物的大数量和在Changjiang河口的咸度的变化，由在高度混浊的系统的咸度和腐植质的联合效果的有细密纹理的沉积的絮凝过程上的学习具有为混浊最大值(TM)的形成的机制的理解的批评意义。为有机化合物的大数量和在Changjiang河口的咸度的变化，由在thehigh混浊的系统的咸度和腐植质的联合效果的有细密纹理的沉积的絮凝进程上的学习具有为混浊最大值(TM)的形成的机制的理解的批评意义。fine-grainedsediments上的咸度和腐植质的效果通过flocculation/coagulationpower(F)，直径(D)和动电位(Z)的方面的合成学习被分析了。并且絮凝物过时的人或物的小宇宙的配置由使用一台扫描电子显微镜和Fourier变换InfraredSpectrometry分析了。Theresults表演那；(1)随咸度，F和D的增加变得更大并且Z变得更小，并且随腐植质的集中的增加，F变得更小，但是D和Z变得更大；(2)絮凝的小宇宙的配置证明在盐形式的好沉积上的腐植质包装，和絮凝C当模特儿-P-OM(C代表泥土；P阳离子；OMorganic材料)能成功地在Changjiang河口的高度混浊的区域表明有细密纹理的沉积的形成的机制。

简介：RecentbathymetricchangesintheChangjiangEstuaryundertheinfluenceofartificialregulationengineeringsandbasinreservoirshavebeenanalyzedbasedonthemaritimechartssince1997andrecentfieldworks.Theresultsindicateaslighterosionofthechannelsintheupperandmiddleestuary,continuingdepositionandseawardmoveofthemouthbarcrestandintensifyingerosionatthenearshoreseabed.Itisnoteworthythatthemorphologicalevolutioncausedbyintensivehumanactivitiesdominatesoverthechangesfromnatureprocess.First,theriverbesareerodedoverallintheSouthBranch(SB),theSouthChannel(SC)andtheupperandmiddlereachesoftheNorthChannel(NC).Thenearshoreseabedoutsidetherivermouthisbeingerodedslightly,whichisattributedtothedecliningsedimentsupplyfromtheChangjiangBasinduetotheconstructionoftheThreeGorgesDamupstream.Thesedimentabovetheseabedisveryactiveandcoarsened,meanwhile,sandwavesarebecomingmoredistinct.Second,adepositionoccursintheNorthBrach(NB),themouthoftheNC,themouthbarsoftheNorthPassage(NP)andtheSouthPassage(SP)andespeciallythemainchanneloftheNP,whereitshowsamassivesiltationafterthedeepwaterwayproject.Thereasonsfortherecentchangesarenotonlythedynamicstructureinestuarinemouthbars,butalsothesupplyofsedimentresuspensioninalocalandoffshorearea.Meanwhile,thesevereerosionandsiltationinsomereachesisrelatedtotheconstructionofestuarineengineerings.ItisindicatedthattheChangjiangEstuaryisgraduallyself-adjustedandadaptingtothevaryingnaturalfactorsandintensivehumanactivities.Thestudyonthemechanismofself-regulationoftherecentbathymetricchangesintheChangjiangEstuaryhasimportantandpracticalsignificance.

简介：210Pbwasmeasuredduringthe3rdChineseNationalArcticResearchExpeditioncruisetoinvestigateitsspatialpatterninthewesternArcticOcean,aswellasitsrelationwiththethermoclineintheCanadianBasin.Thespecificactivitiesvariedfrom0.04to2.72,<0.013to4.37,and0.1to4.85Bq/m3fordissolved,particulate,andbulk210Pb,respectively,correspondingtorespectiveaveragesof0.65,0.43,and1.08Bq/m3.IntheCanadianBasin,theminimum210Pbactivitiesoccurredinthethermocline,whichwascharacterizedbylowtemperatureof-1.52°Candsalinityof33.1.Combiningthespatialdistributionof210PbandhydrographicalcharacteristicsinthewesternArcticOcean,thisscenariowasascribedtotheeffectivescavengingof210PbwhenthePacificwaterflowedacrosstheChukchiShelf.Quantitatively,thisinterpretationwassupportedbyboththeshorterresidencetimesandhigherscavengingefficiencies(SE)ofdissolved210PbovertheChukchiShelf.ThehighestSEvalueswereobservedintheHeraldShoalandbottomwatersovertheslope.

简介：Inordertotheoreticallystudythebucklepropagationofsubseapipelineswithslip-onbucklearrestors,atwo-dimensionalringmodelwassetuptorepresentthepipelineandanonlinearspringmodelwasadoptedtosimulatethecontactbetweenpipeline’sinnerwallsandbetweenpipeline’souterwallandslip-onbucklearrestor’sinnerwallduringbucklepropagation.Inaddition,somereversespringsareaddedtopreventthewallofleftandrightsidesseparatingfromtheinnerwallofslip-onbucklearrestors.Consideringlargedeformationkinematicsrelationsandtheelastic-plasticconstitutiverelationofmaterial,balanceequationswereestablishedwiththeprincipleofvirtualwork.Thevariationofexternalpressurewithrespecttothecross-sectionalareaofpipelineswasanalyzed,andthelowerboundofthecrossoverpressureofslip-onbucklearrestorswascalculatedbasedonMaxwell’senergybalancemethod.Bycomparingthetheoreticalresultswithexperimentandfiniteelementnumericalsimulation,thetheoreticalmethodisprovedtobecorrectandreliable.

简介：TheEastChinaSea(ECS)isariver-dominatedepicontinentalsea,linkingtheAsiancontinenttothenorthwesternPacificviathelargeriversoriginatingfromTibetanPlateau.TherelevanthugeinfluxofriverinedetritushasdevelopeduniquesedimentarysystemsintheECSduringtheQuaternary,offeringidealterrestrialarchivesforreconstructingQuaternarypaleoenvironmentalchangesandstudyingland-seainteractions.Overall,twocharacteristicriversystemsdominatethesedimentarysystemsandsedimentsourcetosinktransportpatternsintheECS,representedbytheChangjiang(YangtzeRiver)andHuanghe(YellowRiver)forthelargeriversystemandTaiwanriversforthesmallriversystem.Giventhis,thesedimentsderivedfrombothriversystemsbeardistinctfeaturesintermsofparentrocklithology,provenanceweatheringandsedimenttransport.Previousstudiesmostlyfocusoneitherthe‘source’discriminationorthe‘sink’recordsofthesedimentarysystemintheECS,whilethesourcetosinkprocesslinkingthelandandsea,inparticularitstimescale,hasbeenpoorlyunderstood.Hereweintroduceanewly-developeddatingtechnique,the‘comminutionage’method,whichoffersaquantitativeconstraintonthetimescaleofsedimenttransferfromitsultimatesourcetothefinaldepositionalsink.Thisnovelmethodisofgreatsignificanceforimprovingourunderstandingontheearthsurfaceprocessesincludingtectonic-climatedrivenweathering,andsedimentrecyclinginrelationtolandscapeevolutionandmarineenvironmentalchanges.TheapplicationofcomminutionagemethodintheECSwillprovideimportantconstraintsonsedimentsource-to-sinkprocessandmoreevidencesfortheconstructionoflateQuaternarypaleoenvironmentalchangesundertheseuniquesedimentarysystems.更多还原