简介：Unsaturatedradionuclidemigrationexperimentswereconductedinapitinsidethetestinghall.Severaltypesofradionuclideswereusedintheexperiments.Tritiumwasusedasatracerforwatermovementinunsaturatedloess.Otherkindsofradionuclideswerealsousedinordertoobtainfundamentalparametersforradionuclidemigrationsothatfurtherenvironmentalassessmentoflow—levelradioactivewastedisposalcanbecar-riedout.Mechanismsgoverningunsaturatedflowinloess,thatis,principlesofone—waylateralflow,arepresentedqualitativelyinthispaper.Andacontinuumone—dimensionalmodelforradionuclidemigrationtestingisdevelopedbasedontheex-perimentsconductedundertheparticularconditionsatthetestsite.Thedatameasuredfromthetestswerecomparedwithsolutionsofthisone—dimensionalmodel.Resultsshowthatthismodelisfeasibleformodelingradionuclidemigrationinunsaturatedloess.

简介：Basedontheone-dimensionalsalinitytransportequationwithconstantdiffusioncoefficient,andseparatedwaterflowvelocityintorunoffandtidalcurrentwiththesingle-frequencyinanidealizedestuary,thesimplestunsteadyanalyticalsolutionofsalinityintrusionisdeducedandtheestimationformulaofdiffusioncoefficientisobtainedinthispaper.Theunsteadysolutionindicatesthatsalinityprocessinestuariesresultsfromtheinteractionofrunoffandtidalcurrent,anditsamplitudeisindirectproportiontotheproductofthevelocityofrunoffwaterandtheamplitudeoftidalflowvelocityandininverseproportiontothediffusioncoefficientandthetidalangularfrequency,anditsphaselagtidalflowwithπ/2whichrevealsthebasicfeaturesofthemaximumsalinityappearingafterfloodslackandtheminimumsalinityappearingbeforeebbslackundertheeffectofrunoff(theadvanceorlagtimeisrelativetothemagnitudeofrunoffandtidalflow).Accordingtothemeasuredflowvelocityandsalinitydata,thesalinitydiffusioncoefficientcouldbeestimated.Finally,withthefielddataofobservingsitesonthedeepwaternavigationchanneloftheYangtzeEstuary,thediffusioncoefficientiscalculatedandacomparativeanalysisofsimulatedandmeasuredofsalinityprocessismade.Theresultsshowthatthesolutioncancomprehensivelyreflectsthebasiccharacteristicsandprocessesofsalinityintrusionundertheinteractionofrunoffandtidalflowinestuaries.Thesolutionisnotonlysuitablefortheoreticalresearch,butalsoconvenientforestimatingreasonablephysicalparametersandgivingtheinitialconditioninthesalinityintrusionnumericalsimulation.

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简介：CarboncycleisconnectedwiththemostimportantenvironmentalissueofGlobalChange.Asoneofthemajorcarbonreservoirs,oceansplayanimportantpartinthecarboncycle.Inrecentyears,ironseemstogiveusagoodnewsthatoceanicironfertilizationcouldstimulatebiologicalproduc-tivityasCO2sinkofhuman-producedCO2.Oceanicironfertilizationexperimentshaveverifiedthataddingironintohighnutrientlowchlorophyll(HNLC)seawaterscanincreasephytoplanktonproductionandexportorganiccarbon,andhenceincreasecarbonsinkofanthropogenicCO2,toreduceglobalwarming.Insixtydays,theexportorganiccarboncouldreach10000timesforaddingironbymodelpredictionandinsituexperiment,I.e.TheatmosphericCO2uptakeandinorganiccarbondrawdowninupperseawatersalsohavethesamemagnitude.Therefore,oceanicironfertilizationisoneofthestrate-giesforincreasingcarbonsinkofanthropogenicCO2.Thepaperisfocusedontheironfertilization,es-peciallyinsituoceanironexperimentsinorderthatthefutureresearchismoreefficient.

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简介：Ｐｒｅｌｉｍｉｎａｒｙ　Ｓｔｕｄｙ　ｏｆ　Ｒｅｃｏｎｓｔｒｕｃｔｉｏｎ　ｏｆ　ａ　Ｄｙｎａｍｉｃ　Ｓｙｓｔｅｍ　Ｕｓｉｎｇ　ａｎ　Ｏｎｅ－Ｄｉｍｅｎｓｉｏｎａｌ　Ｔｉｍｅ　ＳｅｒｉｅｓＰｅｎｇＹｏｕｎｇｉｎｇ（彭永清）；ＺｈｕＹｕｆｅｎｇ（朱育峰）ａ...

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简介：StronggroundmotionparametersforShillongplateauofnortheasternIndiaareexamined.Empiricalrelationsareobtainedformainparametersofgroundmotionsasafunctionofearthquakemagnitude,faulttype,sourcedepth,velocitycharacterizationofmediumanddistance.Correlationbetweengroundmotionparametersandcharacteristicsofseismogeniczonesareestablished.Anewattenuationrelationforpeakgroundaccelerationisdeveloped,whichpredictshigherexpectedPGAintheregion.Parametersofstrongmotions,particularlythepredominantperiodsanddurationofvibrations,dependonthemorphologyofthestudiedarea.ThestudymeasureslowestimatesoflogarithmicwidthinShillongplateau.Theattenuationrelationestimatedforpulsewidthcriticallyindicatesincreasedpulsewidthdependenceonthelogarithmicdistancewhichaccountsforgeometricalspreadingandanelasticattenuation.

简介：因为他们能容易与二维、三维的数字模型相比被规划并且花去更少的时间，一个维的数字模型流行地在沉积运输研究被使用。特别地，他们拥有更大的能力与许多支流在大河盆被使用。这篇论文论述能够精明的全部负担的沉积运输的一个一个维的数字模型。cross-section-averaged沉积运输能力和恢复系数在推迟的负担模型被探讨。因此，这个一个维的模型能在黄河被用于好推迟的负担并且到hyperconcentrated流动。而且，为不稳定的不一致的推迟的沉积运输的方程的一个新discretization计划被建议。模型用在黄河上在Hongshui河和Sanmenxia水库里从Yantan水库测量的数据被校准。有地大小的计算的水水平和河床变丑的比较证明改进数字模型能够预言处于各种各样的状况排序的流动，沉积运输，床变化，和床材料，与合理精确性和可靠性。

简介：Aciladivaricata(Hinds,1843)andA.mirabilis(AdamsandReeve,1850)arecommonbenthicbivalvesinChina.Anumberofresearchershaveproposedthatthelatterspeciesisajuniorsynonymoftheformerspecies.Becauseofmorphologicalsimilarities,itisdifficulttodistinguishthesetwospeciesbasedonvisualexaminationonly.Forbetterunderstandingoftheirtaxonomy,themitochondrialCOIgenefragmentsoffiveindividualsofA.divaricatafromtheEastChinaSeaandsixindividualsofA.mirabilisfromtheYellowSeaweresequencedinthisstudy.ThephylogeneticrelationshipsoftheobtainedCOIsequences,togetherwithnineteensequencesofthreespeciesofthegenusNucula,wereanalyzed.Thepairwiseintra-andinter-specificdistancesfortheCOIsequencesrangedfrom0.002to0.017andfrom0.128to0.134,respectively,andnooverlapwasfound.Phylogenetically,A.divaricataandA.mirabilisformdistinctcladesandclusterintoasistertoallotherNuculaspecies.TheresultsindicatedthatA.divaricataandA.mirabilisaretwodistinctspecies.Thedifferencesinthemorphologyanddistributionbetweenthetwospecieswerebrieflydiscussed.

简介：尽管水和土壤保存活动减少水库沉积，水库在搬运沉积愿望经验沉积的高数量的河边喂了，是不可避免的。Ghezel-Ozan和Shah-Roud河，流动到Sefid-Roud水库水坝，两个都是高度沉积沉重的并且在两床负担和推迟的负担形式把沉积的重要数量搬运到水库。因此，把沉积从水库移开的看起来唯一的实际方法是用一种过嘴的酒方法外面冲洗它。在现在的纸，在以前的年里拿的一种过嘴的酒操作特征的地大小被介绍，并且模仿这个过程的一个数字模型被介绍。在校准以后，用域的模型测量了数据，计算结果(为涌出的水库压力和释放沉积体积)数字模型与为一样的一种过嘴的酒操作的另外的测量数据相比，结果同意很好。用数字模拟结果，当保存水库水被介绍时，最后，最好来临保证高度有效的涌出(至少为Sefid-Roud水坝)。底部插头门，产量自记水位计的形状，和水库水水平的操作变化在涌出期间被优化。另外，数字模型和相关参数，需要被校准，被讨论。

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简介：在东方半球的PKP(DF)的变细以同时解释一种思索的关系的多重散布被检验，相应于强壮的变细的一个相对快的速度异例。有一个维的随机的速度变化的反射率synthetics与振幅比率和微分旅行为赤道的路径PKP(Cdiff)-PKP(DF)预定的PKP(DF)/PKP(Cdiff)的观察相比。有5%，6%，和7%的标准差在的P波浪速度变化的Gaussian分布最高内部核心的200km在是比在东方半球的典型结构稍微快的速度结构上被附加，根据仅仅一个维的结构被考虑，它是可能的解释旅行时间和振幅数据。在二的scatterer分发特征、三尺寸的统计数值的进一步的考试被要求获得一个现实主义的结论。

简介：Theeffectsofhighermodesandtorsionhaveasignificantimpactontheseismicresponsesofasymmetric-plantallbuildings.Aconsecutivemodalpushover(CMP)procedureisoneofthepushovermethodsthathavebeendevelopedtoconsidertheseeffects.Theaimofthispaperistomodifythe(CMP)analysisproceduretoestimatetheseismicdemandsofone-wayasymmetric-plantallbuildingswithdualsystems.Ananalysisof10-,15-and20-storyasymmetric-planbuildingsiscarriedout,andtheresultsfromthemodifiedconsecutivemodalpushover(MCMP)procedurearecomparedwiththoseobtainedfromthemodalpushoveranalysis(MPA)procedureandthenonlineartimehistoryanalysis(NLTHA).TheMCMPestimatesoftheseismicdemandsofone-wayasymmetric-planbuildingsdemonstrateareasonableaccuracy,comparedtotheresultsobtainedfromtheNLTHA.Furthermore,theaccuracyoftheMCMPprocedureinthepredictionofplastichingerotationsisbetterthantheMPAprocedure.ThenewpushoverprocedureisalsomoreaccuratethantheFEMAloaddistributionandtheMPAprocedure.

简介：vadose地区的厚度在垂直地下水起一个关键作用再装。自从过去的十年起，水桌子的衰落在诺思中国平原由于长期的地下水在利用上导致了深vadose地区。一个维的易变地浸透的流动模型被Hydrus-1D软件建立，模拟分别地在稳定、连续的衰退的水桌子下面被运用估计vadose地区的厚度的增加的影响在上再装进程，数量并且再装时间。Luancheng区域被选择到估计再装就稳定、连续的衰退的水而言的数量桌子。模拟结果证明vadose地区延期的厚度的增加再装浇的过程桌子。recharge数量首先减少然后与水桌子的衰落仍然保持稳定。在衰退的水桌子的条件下面，评估在水由流动再装桌子过高估计recharge数量。一般水准年度再装Luancheng区域的率是134mm/a。

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简介：Thebasin-rangecouplingrelationisaleadingsubjectofthemoderngeology.Ingeometry,relationsofthistypeincludecouplingsbetweenstretchedorogenicbeltanddown-faultedbasin,compressionalorogenicbeltandforelandbasin,strike-sliporogenicbeltandstrike-slipbasinandsoon.Faultchainsarethekeyforthesecouplingsandtherearetypicalexamplesforallthesecases.TheNorthChinadown-faultedbasiniscoupledwestwiththeTathanguplift,eastwiththeJiao-LiaoMountains,northwiththeYanshanorogenicbeltandsouthwiththeDabieorogenicbelt,thatistosay,thecentraldown-faultedbasinandthesurroundingorogenicbeltsbearacouplingrelationwithinauniformdynamisticsystem.Studyshowsthatthecentraldown-faultedbasinandtheNorthChinamantlesub-plumestructurehaveacloserelationduringtheirformation.Owingtointensivemantlesub-plumeuplifting,thebottomofthelithospheresufferedfromresistance,whichcausedthelithosphereoftheeasternNorthChinatobeheated,thinnedandfault-depressed.Meanwhile,mantlerocksthatweredetachedoutwardsintheshapeofmushroomwasdissectedbysurroundingductileshearingzones,whichleadtodecompressionandunloadingtogeneratehypomagmas,andaseriesofmantle-branchstructureswereformedaroundthedown-faultedbasin.Thereisanobviouscomparabilityamongthesemantlebranchstructures(orogenicbelts),andtheyhavebasin-rangecouplingrelationswiththecentraldown-faultedbasins.

简介：Aone-dimensionaltime-dependentphotochemicalmodelisusedtosimulatetheinfluenceofion-producedNOxandHOxradicalsontheAntarcticozonedepletioninpolarnightandpolarspringatalatitudeof73degreessouth.Verticaltransportandnitrogen-oxygen(NOx).hydrogen-oxygen(HOx)productionbyionicreactionshavebeenintroducedintothemodel.NOxandHOxproducedbyprecipitatingionsaretransportedintothelowerstratospherebyverticalmotionandhavesomeeffectsinthedevelopmentoftheAntarcticozonedepletion.Fromwinterthroughspringthecalculatedozonecolumndecreasesto269.4DU.However,thisvalueissignificantlyhigherthanthetotalozoneobservedatseveralAntarcticozonestations.

简介：象lumped参数模型那样的分离模型和有限元素模型广泛地在地震的土壤扩大的解决方案被使用。然而，任何一个模型都精确地不估计土壤沉积物的自然频率，也不模仿一抑制频率独立。这研究基于模式等价方法为分层的土壤沉积物的一个维的粘弹性的反应分析开发一个新分离模型。新分离模型是一系列集中的群众，弹簧和缓冲筒与一种特殊配置描绘的一个一个维的相等的multi-degree-of-freedom(MDOF)系统。相等的MDOF系统的动态反应是导出的经分解，物理参数以形式的性质被提出。相等的MDOF系统与可得到的理论解决方案通过扩大函数的比较被验证。在相等的MDOF系统的自由(DOF)的度的适当数字被估计。有存在的相等的MDOF系统的比较研究分离模型被执行。建议相等的MDOF系统罐头确切介绍土壤存款抑制的自然频率和hysteretic并且向更精确的结果提供更少DOF，这被显示出。

简介：Mangrovesaccumulatesedimentarysequences,wherecorescanprovidehistoricalrecordsofmangroveevolutionwithpastclimatechangeandhumanactivity.ThestudytracedthehistoryofmangroveevolutionduringthepastonehundredyearsinamangroveswampofMaoweiSea,SWChina.Thesedimentationrates(0.38-0.95cmyr-1)werecalculatedonthebasisofln(210Pbxs/Al)andmassdepthinthecoresediments.Chemicaltracers,suchasδ13CorgandC:Nvalues,wereutilizedtotracethecontributionofmangrove-derivedorganicmatterusingaternarymixingmodel.Becauseofpotentialdiageneticalterationand/oroverlapintheisotopicsignaturesofdifferentcomponents,simultaneoususeofmangrovepollendiagramscanhelptosupplementsomeoftheselimitations.Combinedwithmangrovepollen,mangroveevolutionwasreconstructedandcouldbedividedintothreestages:flourishment（1886-1905AD）,slightdegradation（1905-1949AD）andrapiddegradationperiod（1949-2007AD）,whichwasconsistentwithpreviousreports.Thereclamationofmangroveswampstoshrimppondswasthemajorreasonforrapiddegradationofmangroveecosystemsinrecentyears,ratherthanclimatechangeintheregion.