简介：Determinationofsedimentstabilityinthefieldischallengingbecausebedshearstress(BSS),adeterminingfactorofsedimenterosion,can’teasilybedirectlymeasured.Totacklethischallengeandreliablyassesssedimenterodibilityinafastflowingriver,astandaloneunderwatercamerasystemandanewinsituflume(ISF)weredevelopedandappliedinthisstudy.ThecamerasystemwasusedtorecordsedimentmovementandthenewISFwasusedformeasuringcriticalbottomshearstress(CBSS).Thecameracanbedeployedaloneinwatertorecordvideosortakepictureswithlightemittingdiode(LED)lightingandflexibleschedulesettings.TheISFisbasedontheconceptthattheamountofforceneededtoerodethesameparticleunderdifferentflowconditionsshouldbesimilar.TwohighresolutionAcousticDopplerCurrentProfilers(ADCP)alsoweredeployedinthefieldtocollectvelocity-depthprofileswhichareusedbyconventionalmethodstocalculateBSSwiththelawofthewall.ThesedimenterodibilitywasthenassessedbasedonthecomparisonbetweentheobtainedCBSSandBSSandthenfurtherverifiedwiththerecordedobservationsfromthedeployedcamera.Theresultsrevealthatthewidelyusedconventionalmethodcanproducelargeuncertaintiesandisnotadequatetoprovidemeaningfulconclusionundertheseconditions.

简介：-ThispaperdescribesaradioactivetracerexperimentcarriedoutatthelandwardspoilsiteoftheNorthPassageintheYangtzeEstuaryinJune,1991.Scandium-46wasselectedasthetracer,thetotalactivityreleasedwas179.45GBqandtheamountoftheSandium-46glasswas495g.Thepurposeoftheexperimentwastodeterminethesedimentmovementdirection,path,velocityandtransportrate,andtherefore,toprovidedirectevidenceforusingthelandwardspoilsiteinthefuture.Theexperimentalresultsshowedthatthesedimentmovementwasgovernedbytheebbtidecurrentduringtheperiodofmeanandneaptideswhentheradioactivetracerwasinjectedbothonthefloodandebbtides,andthesedimentmovedfromthereleasepointtothemiddleoftheNorthPassagenearnavigationbuoyNo.269.Thedirecitonofthesedimentmovementwas110°,theparticlevelocitywas758m/d,andthesedimenttransportrateperunitwidthwas47.8m3/md.

简介：推迟的沉积的遥感上的量的申请是遥感学习的设计申请的一个重要方面。在这份报纸，厦门海湾被选择为学习区域。遥感数据的十一个不同阶段被选择建立一个量的遥感模型由使用遥感图象和伪同步的测量沉积数据印射推迟的沉积。基于开发的实验统计是在即时推迟的沉积集中和集中以及变换在表面层之间建模的平均tidally的推迟的沉积之间的变换模型推迟的沉积集中和平均深度的推迟的沉积集中。在这个基础上，量的应用程序推迟的沉积的遥感上的综合模型被开发。由象多时间的遥感图象一样使用这个模型，平均的多年推迟了厦门海湾的沉积集中被预言。在模型预言和多年平均的观察数据表演之间的比较象附近的地点的集中差别一样推迟了学习地点的沉积集中能被遥感模型很好与21.61%的错误率或更少预言，它能满足隧道免职计算的设计要求。

简介：-ThedataoflandsatTMofmulti-temporalforLingdingyangEstuary,PearlRiverinChinaisfirstlyusedwithsuspendedsedimentconcentrationoffieldmeasurementtoestablishacorrelativemodelequation.AftertheratioprocessingofTMdataandatmosphericcorrection,theimagesofsuspendedsedimentconcentrationofdifferenttemporalsareexportedfromtheimageprocessingsystemsAREISIIandIII.Theseimagesexpressthecharacteristicsofsuspendedsedimentdistribution,themodeofsedimenttransportandtheextentofdispersionundertheactionsoftidalcurrentandwindconditionofdifferentseasons.

简介：DescribedisaninitialattempttosimulatethesuspendedsedimentdynamicsrelatingtotidalandwaveforcingduringsummertimeinJune1980andAugust1981fortheYellowandEastChinaSeascontinentalshelf.Thecohesive/non-cohesivesedimentresuspensionandmovementgeneratedbytheinteractionbetweencurrentandwavearemodeledbyuseofECOMSEDandWAMCycle4.ModelresultsarecomparedwithobservationsinUS-ChinaMarineSedimentationDynamicsProgramperformedfor1980-81atofftheChangjiangestuary.Themainfeaturesofsimulationsshowthatsuspendedsedimentconcentrationsduringthesummerdecreasedmarkedlyoffshoreasobservedduringthesimulationperiods.Asforsomediscrepanciesforthemouthoftheestuarywithhighriverdischarges,i.e.,theChangjiangRiver,themodeldidnotproperlyreproducetheover-mixingsituationinthesummer;thusdistinctverticalconcentrationvariationinthislocalregionisnotagreeablewithobservation.However,generaldispersalpatternsofsuspendedsedimentmovementseemtobeagreeablyreproducedforthenearshoreshallowregion.Someoftheproceduresofsimulationandresultsarepresentedanddiscussed.

简介：Themultibeamsonarscanprovidehydrographicqualitydepthdataaswellasholdthepotentialtoprovidecalibratedmeasurementsoftheseaflooracousticbackscatteringstrength.Therehasbeenmuchinterestinutilizingbackscattersandimagesfrommultibeamsonarforseabedtypeidentificationandmostresultsareobtained.Thispaperhaspresentedafocusedreviewofseveralmainmethodsandrecentdevelopmentsofseafloorclassificationutilizingmultibeamsonardataor/andimages.Theseareincludingthepowerspectralanalysismethods,thetextureanalysis,traditionalBayesianclassificationtheoryandthemostactiveneuralnetworkapproaches.

简介：Gneiss-distilledwaterinteractionatroomtemperaturewasinvestigatedwithbatch-reactorstostudywater-rockreactionandgeochemicalevolutionoftheaqueousphasewithtime.Theionconcentrationsinwaterwerecontrollednotonlybythedissolutionofprimaryminerals,butalsobytheprecipitationofsecondaryminerals.Thedecreasingfractionsizesofgneisscouldfavordissolutionandprecipitationsimultaneously.Ca2+andK+werethemajorcations,andHCO3-wasthemajoranioninwater.AlltheionsexceptCa2+increasedinconcentrationwithtime.TheCa2+releasefromtherocktotheaqueousphasewasinitiallymuchfasterthanthereleaseofK+,Na+andMg2+.Butafterabout5-24hours,theCa2+concentrationsinwaterdecreasedveryslowlywithtimeandbecamerelativelystable.Duringtheexperiment,thewatervariedfromtheCa-(K)-HCO3-typewatertotheK-Ca-HCO3-typewater,andthentotheK(Ca,Na)-HCO3-typewater.Thewater-gneissinteractionwasdominatedbythedissolutionofKfeldsparinthesolution.Theremainingsecondarymineralsweremainlykaolinite,illiteandK(Mg)-mica.

简介：Waterstridersareinsectslivingonthewatersurface,overwhichtheycanmoveveryquicklyandrarelygetwetted.Wemeasuredtheforceoffreewalkinginwaterstriders,usingahairattachedtotheirbacksanda3Dstraingauge.Theerrorwascalculatedbycomparingforceanddataderivedfromgeometryandwasestimatedas13%.Femalesonaveragewerestronger(1.32mN)thanmales(0.87mN),however,theratioofforcetoweightwasnotsignificantlydifferent.Comparedwithotherlighterspecies,Aquariuspaludumseemsstronger,buttheratioofforcetoweightisactuallylower.A.paludumappliesabout0.3mN·cm-1to0.4mN·cm-1withitsmid-legs,thusavoidingpenetratingthesurfacetensionlayerwhilepropellingitselfrapidlyoverthewatersurface.WealsoinvestigatedtheexternalmorphologywithSEM.Thebodyiscoveredbyeffectivelytwolayersofmacro-andmicro-hairs,whichrendersthemhydrophobic.Thesetaearelong(40μm-60μm)andstiff,beingresponsibleforwaterproofing,andthemicrotrichiaaremuchsmaller(<10μm),slender,andflexible,holdingabubbleoverthebodywhensubmerged.

简介：Theutilizationofreclaimedwatercouldbeanefficienttooltoalleviatewaterscarcity,especiallyfordryriveraugmentation.However,itiscrucialtomonitorwaterqualitytoensuresafetytohumanhealthandtoavoidnegativeeffectsontheenvironment.ReclaimedwatersampleswerecollectedbimonthlyfromMaytoNovemberin2010inChaobaiRiver,andthephysiochemicalparametersweredetermined.Themainresultsareasfollows:Theparametersexceedingthethresholdvalueofthewaterguidelinesaremainlynutritionrelatedtonitrogenandphosphorus,whichareknowntoincreasetheriskofeutrophicationinsurfacewaters.Additionally,nitriteandnitratecanbedetrimentaltohumanhealth.ThemajorityoftheparametershaveapeakingconcentrationinMay,whereasotherseithershowsignificanttemporalvariationovertheentireperiodorremainrelativelyconstantinallfourmonths.Correlationanalysisshowsthatsomeparameters(pH,TandB)havenosignificantcorrelationwithothers,whereassignificantpositivecorrelationwasfoundforSrwithECandTDS,forCIwithTDS,forSi02withTPandforNO3-NwithTNandasignificantnegativecorrelationbetweenSO4andBa.Accordingtoprincipalcomponentanalysis,60.108%ofthetotaldataisrepresentedbydominantsolutes,andthesecondprincipalcomponentwithapercentageof31.876comprisesparametersrelatedtonitrogen.Subsequentclusteranalysisofparametersidentifiedfourgroups,whichrepresentdifferentcompositions,andsamplesinMaydifferfromothers.

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简介：Confinementcaninduceunusualbehaviorsofwater.Inspiredbythefabricationofcarbonnanotubeswithnoneircularcrosssections,weperformedmoleculardynamicssimulationstoinvestigatethemo-bilitiesofwaterconfinedincarbonnanochannelswithcircular,square,andequilateraltriangularcrosssectionsoveravarietyofdimensions.Wefindthatwaterexhibitsdisparatemobilitiesacrossdifferenttypesofchannelsbelow0.796nm^2.Notably,comparedwiththeothertwochannels,waterinequi-lateraltriangularchannelsdisplaysthegreatestmobilities.Moreover,at0.425nm^2,differentorderedstructuresarefoundinthethreechannels,andwaterinsidethesquarechannelexhibitsanextremelylowInobility.Itisalsofoundthatabove0.796nm^2,themobilitiesalongthetubeaxisofwatercon-vergetothatofthebulk.Thesephenomenaareunderstoodbyanalyzingthestructure,dynamics,andhydrogenbondingofwater.Ourworkexploresthemobilitiesofwateracrossnoncireularcarbonnanoehannels,whichmayexpandtheprospectofnoneireularnanochannelsinscientificstudiesandpracticalapplications,suchasdesalinationanddrugdelivery.

简介：Thewatersupplyanddrainagesystemisverycruciiilforfulfillinglhebasicneedsofhumanlife,llisalsooneoflliemostimporlantlifesupportingsvsiemsforurbanpopulations.Thetradilionalwatersupplysystemcanbeclassifiedindifferentways.Functionally,itisclassifiediiuotwosystems,i.e.,watersupplysystemandwaterdrainagesystem,whichworkseparatelyand

简介：Anovelapproachhasbeendevelopedtodeterminetheamountofresidualwaterinhumanerythrocyteatroomtemperaturebyelectronicparticlecounter.Naclsolutionsof13osmolalitieswerepreparedandtheequilibriumcellvolumesinwhichweremeasuredonebyone.Theisotonicvolume,Vo,wasobtainedundertheisotoniccondition.ThemeanRBCvolumesof5donorsateachosmolalitywerefittedaccordingtoBoylevan'tHoffrelationship,andtheosmoticallyinactivevolume,Vb,oferythrocytewasthendetermined.TheresultsshowthatVb＝50%Vo.Moreimportantly,thefinalcellvolumewithregardtothesolutionofthehighestconcentrationfoundtobekeptatabout0.5V0.Thedifferencebetweenthesetwovolumesisunconspicuous.Accordingtothepublisheddatathatnon-watervolumeofhumanerythrocyteisabout28.3%ofitsisotonicvolume,residualwaterofhumanerythrocytecanbegainedbysubtractingVdryfromVf,thatisVrw----21.7%VoThenitwasconcludedthattheresidualwaterofhumanlaysin2states,oneisboundwater,andtheotherisfreewater.

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简介：英语中water一词意义非常丰富,它不单单指水,还可以指水源、水运、矿泉水以及在生物体中形成的循环液。人常说:水无定性,英语中也有asunstableaswater(象水一样不稳定,变化无常)之说,也许正是因此而产生了许多由water组成的成语,下面对它们做一个简单的介绍:

简介：Thetriple-to-doublecoincidenceratio(TDCR)methodofliquidscintillationcount-ingisanabsolutemeasurementmethodofradioactivity.TheformulationoftheTDCRmethodandtheestablishedTDCRliquidscintillationcounterarepresentedinthispaper.TheNISTstandardreferencematerial(SRM)oftritiumwaterwasmeasuredtoverifytheperformanceoftheTDCRliquidscintillationcounter.

简介：Asimulationiscarriedoutforthepressurefluctuationdrivenbythewaterhammer,basedonajointuseoftheonedimensionalmethodofcharacteristics(MOC)andthethree-dimensionalfinitevolumemethod(FVM).Thethree-dimensionalvisualizationofthecavitationinducedbythewaterhammerisimplemented,andthetemporalandspatialanalysesofextremeregionsaremade.Apracticalcaseofthewaterhammer,withtheminimumboundarypressurehigherthanthesaturatedvaporpressurecondition,issimulated.Thesimulationpredictionthatthecavitationwouldoccurinthefrontofthegasketcouldservesomeguidelinefortheoptimizationofindustrialdesigns.

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