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7 个结果
  • 简介:Duetoincreasedaerosolemissionsandunfavorableweatherconditions,severehazeeventshaveoccurredfrequentlyinChinainthelast10years.Inaddition,theinteractionbetweentheboundarylayerandtheaerosolradiativeeffectmaybeanotherimportantfactorinhazeformation.Tobetterunderstandtheeffectofthisinteraction,theaerosolradiativeeffectonaseverehazeepisodethattookplaceinDecember2013wasinvestigatedbyusingtwoWRFChemmodelsimulationswithdifferentaerosolconfigurations.Theresultsshowedthatthemaximalreductionofregionalaveragesurfaceshortwaveradiation,latentheat,andsensibleheatduringthiseventwere88,12,and37Wm~(–2),respectively.Theplanetaryboundarylayerheight,daytimetemperature,andwindspeeddroppedby276m,1°C,and0.33ms~(–1),respectively.Theventilationcoefficientdroppedby8%–24%forinthecentralandnorthwesternYangtzeRiverDelta(YRD).Theupperleveloftheatmospherewaswarmedandthelowerlevelwascooled,whichstabilizedthestratification.Inaword,thedispersionabilityoftheatmospherewasweakenedduetotheaerosolradiativefeedback.AdditionalresultsshowedthatthePM_(2.5)concentrationinthecentralandnorthwesternYRDincreasedby6–18μgm~(–3),whichislessthan15%oftheaveragePM_(2.5)concentrationduringtheseverelypollutedperiodinthisarea.TheverticalprofileshowedthatthePM_(2.5)andPM_(10)concentrationsincreasedbelow950hPa,withamaximumincreaseof7and8μgm~(–3),respectively.Concentrationsreducedbetween950and800hPa,however,withamaximumreductionof3.5and4.5μgm~(–3),respectively.Generally,theaerosolradiativeeffectaggravatedthelevelofpollution,buttheeffectwaslimited,andthishazeeventwasmainlycausedbythestagnantmeteorologicalconditions.Theinteractionbetweentheboundarylayerandtheaerosolradiativeeffectmayhavebeenlessimportantthanthelarge-scalestaticweatherconditionsfortheformation

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  • 简介:在在中间之间的过渡时期并且晚三叠纪,印度支那造山运动在华南引起了二构造事件:(1)形成并且沿着华南板的北边缘Qinling-Dabieorogenic带高举,由于它有北方中国板的碰撞;并且2)在华南板的东南的部分的1300-km-wideintra大陆人orogen的发展,它导致了低岬戳褶层地区的一个向西北的运动。这些构造事件结果Yangtze站台的intheending,并且是从Eidacaran的一个稳定的paleogeographic因素到中间的目的三叠纪。这个平台被浅水的碳酸盐的普遍发展描绘。在Yangtze站台的结束以后,上面的Yangtze低岬盆(或四川低岬盆)被形成在期间晚三叠纪并且成为了由Xujiahe形成的相关阶层构成的河的存款的一个累积地点。在西方的四川省,Xujiahe形成躺形成浅水的碳酸盐Xiaotangzi形成siliciclastic岩石摇的Maantang(从架页岩到沿岸的外形)。sequence-stratigraphic框架上面在上面的Yangtze低岬盆三叠纪显示特别冲积体系结构,由创作的序列描绘了(1)高住所的阶段的低精力的河的存款的继任包括煤缝接,并且(2)低住所的阶段的高精力的河的存款,包括混合河隧道沙岩。属于Xujiahe形成和它的相对阶层的这些河的存款的空间分发被渐渐的变瘦外面描绘,重叠,并且向东方和南方的拧外面。这个沉积记录因此在低岬盆的充满的继任以内表示河的存款的特别sequence-stratigraphic继任。sequence-stratigraphic框架为上面在上面的Yangtze区域三叠纪提供Yangtze站台和上面的Yangtze低岬盆的形成的结束的一个记录。

  • 标签: 层序地层格架 中国南方地区 长江上游地区 晚三叠纪 河流沉积 前陆冲断带
  • 简介:TheThreeGorgesProject(TGP)isaworldknownprojecttoutilizeandmanagethewaterresourcesoftheYangtzeRiver.Thereservoirstoreswaterattheendofthefloodseason,andreplenishesdownstreamreacheswithwaterindryseasons.Inadditiontosuchbenefits,theTGPhasirreversiblychangedthehydrologicalprocessandtheriver-lakerelationofthemiddleandlowerreaches.Inthispaper,ahydrodynamicmodelwasestablishedtoquantifytheimpactoftheTGP'soperationonthewaterexchangebetweenDongtingLakeandtheYangtzeRiverduring2009–2013.Theresultsindicatedthat:theoperationoftheTGPhasconsiderablyreducedthepeakdischargeandthefloodvolumeofthemainstreamandtheDongtingLakearea.TheinflowvolumefromtheYangtzeRivertoDongtingLakeviathreeoutletsdecreasedby1.9–3.5billionm3/yr,whiletheoutflowvolumefromDongtingLaketotheYangtzeRiveratChenglingjiincreasedby0.3–1.6billionm3inSeptemberand0.4–0.6billionm3inOctober,respectively.Thisresearchprovidesvaluableinformationforfloodcontrol,irrigation,andwaterallocationinthemiddleandlowerreachesoftheYangtzeRiver,andservesasatypicalcaseforinvestigatingtheimpactofotherhydropowerprojectsaroundtheworld.&2017InternationalResearchandTrainingCentreonErosionandSedimentation/theWorldAssociationforSedimentationandErosionResearch.PublishedbyElsevierB.V.Allrightsreserved.

  • 标签: THREE Gorges Project YANGTZE River Dongting
  • 简介:在直径的10m的一个浮标被用来在垂直侧面记录当前的速度和方向在近海Changjiang(长江)河口的区域(与46.0m的平均的水深度)为一年。结果包括:(1)水流顺时针方向旋转并且没有清楚的季节的变化,当前的方向在垂直侧面是一致的。(2)水平当前的速度通常高,与发生在夏天的128.5cm/s和出现在离表面通常靠近的冬季的105.5cm/s的最大值。在在一样的垂直侧面秋天的平均当前的速度变化(差别是不到8.0cm/s),与发生在夏天的47.0cm/s和在冬季的40.8cm/s的最大值。平均当前的速度在春天潮期间是两次那在小潮潮(26.5cm/s)期间。(3)速度的重要差别在垂直侧面被观察。最大的当前的速度发生在任何一个表面(春天和冬季)或表面下(夏天和秋天),以出现在底部的最小的当前的速度。所有层的最大的平均当前的速度是57.9cm/s,它在夏天期间发生在18-m层。(4)剩余水流的平均速度从7.5cm/s到11.3cm/s,与在春天的最强壮的发生并且在冬季最弱。所有层的剩余水流在春天和冬季期间是东方的,而向东北或向北方在夏天和秋天期间。(5)水流在Changjiang河口近海被冲淡的Changjiang河分泌物,台湾温暖的水流,季风和潮一起影响。

  • 标签: 长江口 海流特征 浮标 电流速度 平均电流 近岸
  • 简介:TheVRDSfeedstockprocessedinrefineriesalongtheYangtzeRiverhasspecialcharacteristics,includinghighFeandCacontent,andlowsulfurandhighnitrogencontent.Dependinguponfeedstockpropertiesandoperatingconditions,someapproacheshavebeendevelopedbytheSINOPECResearchInstituteofPetroleumProcessing(RIPP),whichincludeinstallingthedecalcificationfacility,developingnewguardcatalystsandHDCCRcatalysts,implementinganewcatalystgradingapproach,developingahighlyefficientdistributiontechnologyandapplyingRICPprocessinsomerefineries.Theapplicationeffectshaverevealedthattheintegratedtechnology,whichcanbeconducivetothelong-cycleoperationdevelopedbyRIPP,canmaximizethedepositsuptakecapacityoftheguardreactorandtheactivityofgradingcatalysts.

  • 标签: FEEDSTOCK CHARACTERISTICS DECALCIFICATION guard CATALYST HDCCR
  • 简介:AfteroperationoftheThreeGorgesProject(TGP),thereisanewevolutiontendencyforriversandlakesinthemiddlereachesoftheYangtzeRiver(i.e.theChingRiverreaches).Inrecentyears,theweakeningconnectionrelationshipbetweentheYangtzeRiverandDongtingLakehasresultedinaseriesofproblemsforfloodregulation,waterresourcesutilization,andaquaticecosystemprotectionintheriver-lakejointarea.Inthispaper,thehydrologicalcharacteristicsandfluvialprocesseswithintheriver-lakejointareaarestudied,andpossiblemanagementstrategiestomaintaintheconnectedriver-lakerelationshipareproposed.Toachievethisobjective,theevolutiontendency,suchasthezero-flowproblemandriverregimeforthreemajoroutlets(i.e.theSongziOutlet,TaipingOutlet,andOuchiOutlet)toDongtingLakefromtheYangtzeRiver,isanalyzed.ItisbelievedthattheSongziOutlethasacomparativeadvantageinflowdiversionovertheothertwooutlets.TheRangeofVariabilityApproachisintroducedtoidentifyhydrologicalcharacteristicsattheSongziOutlet.Severalcharacteristicvaluesofflowdiversionfromthisoutletduringdroughtperiodsaredetermined.Then,thefluvialprocessesintheriver-lakejointareaarestudiedbycomparingtopographicmapsandusingcontrolgaugestationdataofvariousyears.ThewaterandsedimentfluxareanalyzedbeforeandafteroperationoftheTGP.Finally,basedontheresultsobtained,twopossiblemanagementstrategiesarerecommendedandcorrespondingparametersareestimatedtostrengthenandmaintaintheconnectedriver-lakerelationship.ThisanalysistakesintoaccountoperationoftheTGP,mainstreamshiftandincreasingriverbedscourintheChingRiverchannel.Torestoretheflowdiversionconditiontothatinthe1950sor1960s(i.e.140m3/sofflowdiversioncorrespondingto5500m3/sofflowattheZhichengstation),itisestimatedthattheriverchannelaroundtheSongziOutletshouldbedredged1.4munderthecurrentriverbedsituatio

  • 标签: River-lake relationship YANGTZE RIVER Dongting LAKE
  • 简介:ObjectiveTheEmeishanlargeigneousprovince(ELIP)inSWChinaistheonlyonelargeigneousprovinceinChinarecognizedbyinternationalgeologists.PreviousstudiesofELIPoverpasttwodecadesindicatethattheELIPage,duration,scaleandgenerationmechanismarestillcontroversial.Amongthosescientifictopics,some

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