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：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：为在河和水库里监视推迟的沉积集中的自动化、即时、连续的技术能在数量的改进和沉积数据的质量起一个重要作用，并且对水环境，水管理，危险预防，和水资源的管理珍贵。在监视技术的研究检验了使用绝缘的常数的特征检测土壤潮湿和空气水的集中的可能性二阶段的流动，基于沉积，空气和水的绝缘的常数是不同的事实。一个电容传感器被开发监视淤泥在最近的研究的推迟的沉积集中(SSSC)，跟随作为沉积水混合的SSSC增加，水样品的明显的绝缘的常数也增加的原则并且因此，电容也由察觉到的系统检测了增加。这被表明在集中的变化淤泥沉积以一种线性方式在观察电容与变化断然相关，并且与电压产量而且以一种线性方式否定地相关。关联系数上面到达了0.98。在估计的集中的全面错误在0.26%和2.91%之间变化。在象产生系统，电极盘子的区域，和样品温度的效果的信号的频率那样的电容传感器系统的元素也被评估了。说明的结果电容传感器技术能被用于自动地并且连续地监视SSSC。另外，在实验的SSSC的范围到达了200kg/m3；因此，在监视的实际SSSC的这种技术的应用程序值得进一步的研究。

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.

简介：从长江盆的沉积分泌物在最近的年里有一个逐步的减少趋势。扣押三座峡水库加重了这个减少的趋势并且通过传播效果在长江河口影响了推迟的沉积集中(SSC)的变化。长江河口的SSC数据在19592012期间显示出那：(1)在南方的SSC在河口并且在长江分叉近海海区域显示了减少的趋势并且向海少些减少了。同时，在在SSC和沉积分泌物之间的减少的大小的差别向海变得更大。(2)为北方布朗奇，优先的流动没很变化，但是SSC趋于减少，它被SSC的减少主要在南方布朗奇和中国东方海引起。(3)由于减少的流量和相对加强的潮，在在20032012的浅节移动了的酒吧中的SSC的山峰区域为在19842002与那相比联合起来的大约1/6经度里面，并且里面动人的距离在洪水季节的顺序>年度一般水准>旱季。(4)在南方经过的入口，因为增加由暂停引起了，岸沟交换是，SSC主要减少了不到减少在盆和海区域由锋利的SSC减少引起了。颠倒在中间的节是真的，在SSC显示出一个增加的趋势的地方。(5)在北方经过的入口在减少的流动裂口和沉积裂口比率的联合影响下面，在盆和海区域和暂停的减少的数量的减少的SSC，SSC显示了一个减少的趋势。在中间的节，因为增加的数量由沉积引起了，温习塘是多于减少的数量由外部环境引起了，显著地，SSC趋于增加。整体地，在沉积分泌物的锋利的减少在长江河口引起了同步SSC减少。但是在SSC从盆在沉积分泌物在对锋利的减少的SSC的反应显示了增加的趋势，显示的synchronicity和差别的地方，仍然有区域。

简介：Verticalstructuresofmomentumexchangecoefficientandsedimentconcentrationarethekeysintheresearchonestuarineandcoastalsuspendedsedimenttransport.Basedontheparabolicmixinglengthdistributionpattern,thedistributionpatternofverticalmomentumexchangecoefficientwhichissuitableforestuarineandcoastalwatersisconstructed.AcomparisonwithsteadyflowandmeasuredmomentumexchangecoefficientduringonetidalcycleintheMenaiStraitofEnglandshowsthattheresultofthispatternisclosertothemeasuredvaluesthanthoseofcommonlyusedRouse'sandvanRijn'spatterns,andthepatternisalsosuitableforestuarineandcoastalwaters.Successively,basedonthepreconditionthatmomentumexchangecoefficientisequivalenttosedimentturbulentdiffusioncoefficient,andcombiningwiththeDiffusionTheory,weobtaintheexponentialverticaldistributionpatternofsedimentconcentration,whichisalsosuitableforestuarineandcoastalwaters.Thereby,usingmeasuredverticalstratifiedsedimentconcentrationdataoftheSouthandtheNorthPassagesoftheYangtzeEstuaryandZhoushanarchipelagowatersforfittingcalculation,andcomparingtheresultswiththosefromRouse's(1938)andZhangetal.'s(1989)formulas,theresultsshowthattheexponentialverticaldistributionpatternofsedimentconcentrationobtainedinthepresentstudynotonlyovercomesthedefectofRouse'sformulathatthesurfacesedimentconcentrationwillbe0,butalsohasaholistichigherprecisionalongtheverticallinesthanthoseofRouse'sandZhangetal.'sformulas.

简介：根据在第4中国国家北极研究远征期间在Bering海获得的数据，溶解的氧的分发()被学习，它的最大的集中的原因被讨论，并且在之间的关系并且另外的参数例如咸度，温度，并且叶绿素一被分析。结果证明集中在Bering海盆从0.53～12.05mg/L。上面的水包含了高集中，最大值从20～50m发生在深度范围。当深度比200m深并且从500～1000m在深度范围到达了最小时，集中很快减少，然后慢慢地增加了，深度增加，但是仍然在底层保留了。在架上，DO集中与10.75mg/L的吝啬的价值从6.53～16.63mg/L，并且显示出从北方减少到南方的一个特征。集中在在Bering海和劳伦斯岛之间的区域是更高的并且在在62的纬度的劳伦斯岛的东南和西南是更低的??猯'T伾搠獩牴扩瑵潩?慰瑴牥獮椠?楤晦牥湥?慬敹獲漠?潢桴猠瑩獥

简介：Highconcentrationlayerofcohesivesedimentfrequentlyoccursinmuddyestuariesandcoastalzones,andcausesrapidsiltationofthewaterways.Aonedimensionalverticalcoupledmodeldescribingtheinteractionsbetweenwaves,currentsandsuspendedcohesivesedimentisdevelopedinthepresentpaper.Thenumericalresultsandanalyseswithfieldmeasurementsrevealthemechanismoftheformationandtransportbehaviorsofthelayerundertheactionofwavesandcurrents.

简介：Superoxidedismutase(草皮)是包括海洋的无脊椎动物在各种各样的有机体对反应的氧种类在抗氧化剂小径玩第一根防卫线的关键抗氧化剂酶。在那里主要存在二种特定的形式，Cu/Zn-SOD(SOD1)和Mn草皮(SOD2)，在优核质。草皮被知道被许多环境stressors并发地调制。由使用中央合成试验性的设计和反应表面方法，关节水完成温度(18-34栠杩?潨潭潬祧眠瑩?湫睯?湩敶瑲'O慲整洠汵楴爭灥慥?琭票潭楳獮

简介：Thedistributionofthesuspendedsedimentconcentration(SSC)intheBohaiSea,YellowSeaandEastChinaSea(BYECS)isstudiedbasedontheobservedturbiditydataandmodelsimulationresults.Theobservedturbidityresultsshowthat(i)thehighestSSCisfoundinthecoastalareaswhileintheoutershelfseaareasturbidwaterismuchmoredifficulttoobserve,(ii)thesurfacelayerSSCismuchlowerthanthebottomlayerSSCand(iii)thewinterSSCishigherthanthesummerSSC.TheRegionalOceanModelingSystem(ROMS)isusedtosimulatetheSSCdistributionintheBYECS.AcomparisonbetweenthemodeledSSCandtheobservedSSCintheBYECSshowsthatthemodeledSSCcanreproducetheprincipalfeaturesoftheSSCdistributionintheBYECS.Thedynamicmechanismsofthesedimenterosionandtransportprocessesarestudiedbasedonthemodeledresults.ThehorizontaldistributionoftheSSCintheBYECSismainlydeterminedbythecurrent-waveinducedbottomstressandthefine-grainsedimentdistribution.Thecurrent-inducedbottomstressismuchhigherthanthewave-inducedbottomstress,whichmeansthetidalcurrentsplayamoresignificantroleinthesedimentresuspensionthanthewindwaves.TheverticalmixingstrengthisstudiedbasedonthemixedlayerdepthandtheturbulentkineticenergydistributionintheBYECS.Thestrongwintertimeverticalmixing,whichismainlycausedbythestrongwindstressandsurfacecooling,leadstohighsurfacelayerSSCinwinter.HighsurfacelayerSSCinsummerisrestrictedinthecoastalareas.

简介：TheArcticsea-iceextenthasshownadecliningtrendoverthepast30years.Icecoveragereachedhistoricminimain2007andagainin2012.Thistrendhasrecentlybeenassessedtobeuniqueoveratleastthelast1450years.Inthesummerof2010,averylowsea-iceconcentration（SIC）appearedathighArcticlatitudes--evenlowerthanthatofsurroundingpackiceatlowerlatitudes.Thisstrikinglowiceconcentration--referredtohereasarecordlowiceconcentrationinthecentralArctic（CARLIC）--isuniqueinouranalysisperiodof2003-15,andhasnotbeenpreviouslyreportedintheliterature.TheCARLICwasnottheresultoficemelt,becauseseaicewasstillquitethickbasedonin-situicethicknessmeasurements.Instead,divergenticedriftappearstohavebeenresponsiblefortheCARLIC.AhighcorrelationbetweenSICandwindstresscurlsuggeststhattheseaicedriftduringthesummerof2010respondedstronglytotheregionalwindforcing.ThedrifttrajectoriesoficebuoysexhibitedatranspolardriftintheAtlanticsectorandaneastwarddriftinthePacificsector,whichappearedtobenefittheCARLICin2010.Undertheseconditions,moresolarenergycanpenetrateintotheopenwater,increasingmeltthroughincreasedheatfluxtotheocean.Wespeculatethatthisdivergenceofseaicecouldoccurmoreofteninthecomingdecades,andimpactonhemisphericSICandfeedbacktotheclimate.

简介：在到环境变化的全球碳周期和它的反应理解海洋角色要求观察的高时间空间的分辨率。从多重来源合并海洋颜色数据是减轻单个海洋颜色传感器的限制的一个有效方法(例如，一行宽度和差距，多云或多雨的天气，和阳光闪烁)并且改进时间、空间的范围。自从看海的宽Field-of-View传感器(SeaWiFS)和在2010年12月11日结束的媒介光谱的分辨率成像分光计(MERIS)和2012年5月9日的使命，分别地，可得到的海洋颜色传感器的数字衰退了，关于空间、时间的范围减少合并海洋颜色数据的好处。在现在的工作，中等分辨率光谱中国的成像器(MERSI)/FY-3在处理合并和全球海洋叶绿素的新数据集被增加一(Chl一)集中(2000-2015)从遥感反射被产生(MERIS的Rrs())观察，中等决定的成像光谱辐射计(MODIS)-AQUA,可见红外线的成像辐射计(VIIRS)和MERSI。这些数据资源首先被合成一个集中数据是的统一遥感反射数据，然后Chl用联合Chl的inversed颜色的一个算法基于索引的算法(中央情报局)和OC3。合并数据产品从MERSI的增加在空间、时间的范围显示出主要改进。当MERSI数据在合并过程被增加时，合并产品的平均每日的范围在约9%是约24%全球海洋和增加。采样频率(时间的范围)被联合MERSI数据极大地改进，与到29.9%的从15.6%增加的中部的采样频率(57d／a)(109d／a)。合并Chl一产品此处被验证由在situ大小并且除了省略MERSI和GlobColour和措施用一样的途径把他们与合并产品作比较合并了数据。在新合并Chl之间的关联和相对错误一产品并且没有MERSI的增加，在situ，观察相对合并产品的结果是稳定的。Chl的时间系列集中没有增加MERSI和单个传感器，异例类似于合并产品。新合并产品从GlobColour和措施在约10%合并Chl以内同意一个产品。