简介：训练策略的一条河的选择为更低的黄河(LYR)是极其重要的。当前，宽河的训练策略在训练LYR适用。然而，在在黄河盆的水文学过程的显著变化，以及从在黄河盆的社会经济的开发的立即的压力，使如果有可能性改变从到狭窄河的训练的宽河的训练训练策略的河，考虑必要。这研究调查通过数字模拟在LYR上训练策略的不同的河的影响。一一个维(1-D)模型被用来为未来模仿河的过程50年并且一三维(3-D)模型被使用学习典型洪水。学习集中了于河形态学，结果看那在两水分泌物的在场减少趋势和沉积负担是否坚持，在LYR的免职率将进一步减少不管什么策略被使用。特别，狭窄河的训练能达到目的与宽河的训练相比在LYR增加沉积运输能力。如果到来的水和沉积负担恢复到最后世纪的吝啬的水平，主要隧道收缩不管多么不可避免地由于沉积发生为宽河、狭窄河训练。最重要地，这研究证明狭窄河的训练在整个LYR上减少免职数量，但是它几乎不在减轻推迟的河的发展提供很少帮助。相反，狭窄河的训练能在河模式从高度漫步到蜿蜒地流变化的过渡活动范围引起沉积，进一步的变得更坏在那里的驼峰免职。因为关于在在可行工程的黄河盆，和缺乏的水文学过程的未来变化的无常，测量在LYR减轻推迟的河和驼峰免职问题，小心应该在为LYR训练策略的河里关于变化被行使。

简介：【学习目标】Ⅰ知识目标:1.能理解运用以下词组短语:gothrough,goaround,goover,godown,goaroundabend,gopast,gounder并能简单介绍行进方向;2.能理解运用词组短语的过去式。Ⅱ能力目标:1.通过听力练习,口语练习,能够用英语说明行进方向,并能运用到实际中;2.能在过去式中简单运用词组短语来表达。Ⅲ情感目标:通过对新知识的学习,能够表达自己的想法,能够在实际中用英语说明行进方向;养成合作与共享的习惯。

简介：Itiswell-knownthattheUnitedStates,ahighlydevelopedcountrywhetherinhigh-tech.orhighereducation,isinaleadingpositionintheworld.BasedonthecomparisonandanalysisofhighereducationbetweenChinaandtheU.S.,thisarticlehighlyaffirmstheadvantagesofAmericanhighereducation,offersanobjectivecommentonChina'shighereducationreforminrecentyears,andearnestlyindicatesthatChina'shighereducationneedstobeimprovedinordertofacilitategreaterdevelopment.

简介：Thereisalongrivernearmyhouse.Asmallboatisintheriver.Mysisterissittingintheboat.Sheiswearingayellowdress,thedressisnewandvery.nice.Amanisswimmingintheriver.That'smydad.Heisfreetoday,becausetodayisSunday.

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简介：WaterandsedimentqualitiesarestudiedbyanalyzingsamplestakingfromthemouthsoftheHaihe,Duliujian,NewZiyaandBeipairiversintheHaiheriverbasininnorthChinain2005and2001,inordertofindthechangesofwaterandsedimentpollutions.Theconcentrationsofheavymetals,arsenic,totalnitrogen(TN)andtotalphosphorus(TP)areanalyzedandresultshavebeencomparedforthetwotimes.Thein-situmeasurementforDissolvedOxygen(DO)andSedimentOxygenDemand(SOD)rateswerecarriedattheHaiheandDuliujianrivermouthsin2006.Theresultsshowthatthewatersofthe4rivermouthsarestillseriouslypolluted,thoughmuchimprovedinthecaseoftheHaiheandDuliujianrivers.ThemainpollutantsareTPandTNintheNewZiyaandBeipairiversandmercury(Hg)atall4rivermouths.Comparedwiththosein2001,theconcentrationsofalmostallmetalsandarsenicinthe4rivermouthshavedecreased.WaterqualityatHaiheandDuliujianshowsanimprovingtrend,whilethewaterqualityatBeipaiissimilartothatof2001.Incontrast,waterattheNewZiyarivermouthismoreseverelypolluted.Thesedimentsinthe4rivermouthsarenotseriouslypollutedbyheavymetalsbutarepollutedbynitrogenandphosphorus.Mostofthepollutantcontentsinthesedimentsshowlittlechangebetween2001and2005.Thein-situDOandSODmeasurementshowsthatthewatersattheHaiherivermouthisinthestateofoxygendepletion,andSODisimportantconsumerofDOattherivermouths.Theoverallanalysisshowsthatincreasingwaterpollutionandeutrophicationinwatersfarfromcitiesareongoingcausesofconcern.

简介：Palaeoflood水文学学习是全球变化学习的一个正面的题目。用标明日期方法的沉积科学，地形学和OSL，典型palaeoflood呆滞水存款在Qishuihe河山谷被学习。结果证明分别地，有21个palaeoflood事件的五泛滥事件在Holocene时期期间发生在43004250一B.P，42504190一B.P，41904100一B.P，41004000一B.P和31003010一B.P期间。palaeoflood山峰分泌物与水文学模型一起被计算。与计量洪水，历史的洪水和palaeoflood水文学数据的联合，洪水事件的档案在Qishuihe河山谷，和洪水频率山峰分泌物关系被扩大到超过10,000年曲线精确地被建立。在减轻的起的重要角色充满的这些研究结果冒险，水力的工程并且另外在半干旱的Weihe河盆的水资源的发展。

简介：TheJinshaRiver-LancangRiver-NujiangRiverareaisoneoftheimportantprospectareasfornoblemetalandnonferousmetaldepositsofChina.Ofagreatvarietyofgolddepositspresentinthisarea,thefollowingtypesseemtobeeconomicallymostvaluableandpromising:tectonicalterationtypeinophioliticmelange;polymetallicquartzveintyperelatedtointermediate-acidintrusions;finelydisseminatedtypeinfracturezones;mixedhydrothermaltypeintectonicfracturesofcarbonaterocks;hydrothermaltyperelatedtosubvolcanicrocks;volcanic-hotspringtype;submarinevolcanoexhalation-sedimentary-hydrothermalreformationtype.MetallogenicepochsareexclusivelyMesozoicandCenozoic,andoredepositsandorebodiesarecontrolledbylinearstructures.Magmaticactivityhasaffectedgoldmineralizationinvaryingdegrees,andgolddepositsarebasicallyofmesothermal-epithermaltypewithubiquitousandintensealterations.Ore-formingmaterialsandhydrothermalsolutionsshowmulti-sourcecharacter.

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简介：UsingfieldobservationsatfourgaugingstationsalongtheInnerMongoliaReachoftheYellowRiverinChina,thispaperexploreseffectsoftheiceonthehydraulicsofthisriverreachforfourdifferentconditions,namely:underopenchannelflow,duringice-runningperiod,theice-coveredperiod,andtheriverbreak-upperiod.Theratingcurveswerefoundtobewellrecognizedunderopenchannelsituations,butweresometimespoorlydefinedandextremelyvariableundericeconditions.Theresultsalsoshowthatthewaterlevelisinsensitivetoflowingicepriortofreeze-up.However,significant,buthardlysurprising,variationswereobservedduringice-coveredconditions.Theratingcurvesforboththeicecoveredconditionandrivericebreakupperiodaredevelopedandsomerelatedhydraulicissuesareexamined.Additionally,theimpactsoftheiceaccumulationandassociatedriverbeddeformationduringiceperiodontheratingcurvesarediscussed.

简介：与潜在的涡度(PV)在这篇论文，潜在的涡度结构和在在212003年6月23日期间的长江和Huaihe河山谷上的风暴之发展形成的倒置被调查框架。风暴之发展形成被一个lower-troposphericPV异例主要由于潜伏的热版本在早阶段在长江和Huaihe河山谷上表明，它极大地影响由片表明了明智的PV倒置的联系lower-tropospheric重力势高度和风领域的进化。在以后的阶段，一个upper-troposphericPV异例发展，导致在在两个的气旋上的垅的生长在上游、下游，它为低级气旋发展提供一块有利背景地。但是表面热反常的效果总是在这风暴之发展形成期间阻碍气旋的发展到不同程度。位置和PV异例的力量是，这进一步被表明仔细，与低级气旋有关，开发，和lower-troposphericPV异例似乎例如，组成最重要的特征贡献大约60%到低级喷气(LLJ)。

简介：Residencetimeisanimportantindicatorforriverenvironmentalmanagement.Inthispaper,a3DhydrodynamicmodelhasbeensuccessfullyappliedtoLittleManateeRivertocharacterizethemixingandtransportprocessandresidencetime.Themodelemployshorizontalcurvilinearorthogonalgridstorepresentthecomplexriversystemthatconsistsofbranchesandbayous.Themodelhasbeensatisfactorilycalibratedandverifiedbyusingtwocontinuousdatasets.Thedatasetsconsistofhourlyobservationsofallforcingboundaries,includingfreshwaterinputs,tides,winds,salinityandtemperaturesatbayboundary,andairtemperaturesformodelsimulations.Thedatasetsalsoconsistofhourlyobservationsofwaterlevels,salinity,andtemperatureatseveralriverstations.ThecalibratedandverifiedhydrodynamicmodelwasusedtopredictresidencetimeintheLittleManateeRiver.Undertheminimumflowof0.312m3/s,thepulseresidencetime(PRT)is108days.Modelsimulationswerealsoconductedfor17flowscenarios.EmpiricalregressionequationshavebeensatisfactorilyderivedtocorrelatePRTtofreshwaterinflow.CorrelationcoefficientR2is0.982forPRT.

简介：SeismictomographyfromthePgwavedataalongthenon-longitudinalprofileintheThreeGorgesRegionispresentedinthispaper.Theseismictomographymethod,andtheacquisitionandanalysisofseismictraveltimearebroadlyoutlined.Thetomographyofbasementrevealsagreatamountofsignificantinformationandshowsthatthelow-velocityzoneisduetothelithologicdifferenceandthefaultfracturezone.Italsodemonstratesthatthereexistthreehigh-velocityzoneswithv>6.4km/satthebasement;thelargestofzoneswhichstrikesnorth-southislocatedatthesouthwesternsideofHuanglingAnticlinoriumandextendsintotheanticlinoriumnorthward.Theothertwohigh-velocityzonesare,respectively,situatedattheeasternsideoftheanticlinoriumandthewesternsideoftheprofile.Thehigh-velocityzonesareinferredtooriginatefromtheupwellingofmaterialwithhigh-velocityfromdeepcrust.

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简介：Riverregulationandrivertraininghavebeenperformedforvariouspurposesandnegativeeffectshavebeenshowninnumerouscases.Insomecasesthenegativeeffectsaresoseriousthathumanshavetoconsiderto'renaturalize'theregulatedrivers.Onlybyusingthestrategyofintegratedrivermanagementthediverseriverusesandnaturalfluvialprocessesandecologicalsystemsmaybeharmonized.Basedonanalysisofcasestudiesanddatacollectedfromliteraturesthispaperpresentstheconceptofintegratedrivermanagementandfourprinciplesofrivertraining.Theintegratedrivermanagementcomprises:1)takingthewatershed,upperstreambasinincludingthetributaries,middleandlowerreachesandtheestuaryasanintegratedentityintheplanning,designandmanagement;and2)mitigatingorcontrollingthenegativeimpactsonhydrology,erosionandsedimentation,fluvialprocesses,landuseandriveruse,environmentandecologywhileinachievingeconomicbenefitfromwaterresourcesdevelopment,floodsafetymanagementandhydropowerexploitation.Rivertrainingandmanagementshouldbeinaccordancewiththefourprinciples:1)extendingthedurationofriverwaterflowingonthecontinent,whichmaybeachievedbyextendingtherivercourseorreducingtheflowvelocity;2)controllingvariouspatternsoferosionsandreducingthesedimenttransportationintherivers;3)increasingthediversityofhabitatandenhancingtheconnectivitybetweentheriverandriparianwaters;and4)restoringnaturallandscapes.

简介：TheYangtzeRiveristhelargestriverinChina,about6,300kilometreslongwithadrainageareaandpopulationaccountingfor18.8percentand33percentrespectivelyinChina.AimingatincreasingforestandvegetationareasonthemiddleandupperreachesoftheYangtzeRivertocontrolwaterandsoilerosion,theChinesegovernmentin1989decidedtocommenceaconstructionprojectfortheprotectionoftheforestsystemonthemiddleandupperreachesoftheYangtzeRiver.Theprojectcovers645counties(citiesanddistricts)in13provinces,

简介：<正>WiththerecentannouncementofthewaternowrisingbehindthemassiveThreeGorgesDam(SanxiaBa),IwasremindedofmyjourneydowntheLongRiveratatimewhenthedamwasunderconstructionandthemanycommunitiesalongtheriverstillexistedastheyhaddoneforhundredsofyears.TodaytheregionisattheheartofChina’smodernisationdriveandwillplayWiththerecentannouncementofthewaternowrisingbehindthemassiveThreeGorgesDam(SanxiaBa),IwasremindedofmyjourneydowntheLongRiveratatimewhenthedamwasunderconstructionandthemanycommunitiesalongtheriverstillexistedastheyhaddoneforhundredsofyears.TodaytheregionisattheheartofChina’smodernisationdriveandwillplay

简介：Thereisasmallriverinmyhometown,it'scalledxiuhe,itgoesthroughthevillage.thelandbytheriveriscoveredwithgrass.

简介：TongtianRiverreferstothereachwheretheTutoRiver,theoriginofYangtzeRiver,joinstheTangqu,runningsoutheastandpassingtheBatangoutfallinYushu,theTibetan-inhabitedareainQinghai.Itstretches813km,withadrainageareaof138,000squarekm.

简介：<正>ThescrollofPureBrightnessontheRiverdrawnbytheChinesetraditionalpaintingmasterZeduanZhangdepictsawell-offsceneofDongjing(presentcityofKaifeng),whichwasthecapitaloftheNorthernSongdynastyathousandyearagoandwasthetop-rankingmetropolisatthattime.Thescroll