115GHz CO Emission from the IRAS Selected Star-Formation Regions     

Fu Haowen  Su Bumei  Li Yongsheng 《天文研究与技术》1999,(Z1)

1　ＩｎｔｒｏｄｕｃｔｉｏｎＳｔａｒｆｏｒｍａｔｉｏｎｉｓｏｎｅｏｆｔｈｅｍｏｓｔｅｘｃｉｔｉｎｇｆｉｅｌｄｓｏｆｍｏｄｅｒｎａｓｔｒｏｎｏｍｙ .ＣＯｍｏｌｅｃｕｌａｒｏｕｔ ｆｌｏｗｓｎｅａｒｙｏｕｎｇｓｔｅｌｌａｒｏｂｊｅｃｔｓｗｅｒｅｆｉｒｓｔｄｅｔｅｃｔｅｄｉｎＯｒｉｏｎｒｅｇｉｏｎ (Ｋｗａｎｅｔａｌ.1 976 ) .ＴｈａｎｋｓｔｏｔｈｅｌａｕｎｃｈｉｎｇｏｆＩＲＡＳ (ＩｎｆｒａｒｅｄＡｓｔｒｏｎｏｍｉｃａｌＳａｔｅｌｌｉｔｅ) ,ｔｈｅＩＲＡＳｐｏｉｎｔ ｓｏｕｒｃｅｃａｔａｌｏｇｕｅ(ＰＳＣ) ｐ…  相似文献   

The Near-Nuclear Study of Comet Hale Bopp     

Tao Jun  Qian Bochen  Gu Mingfeng  Tang Yuan  Song Baojun 《天文研究与技术》1999,(Z1)

ＩｎｔｒｏｄｕｃｔｉｏｎＣｏｍｅｔＨａｌｅ Ｂｏｐｐ(Ｈａｌｅ,1 995 )ｉｓａｎｅｘｔｒｅｍｅｌｙｂｒｉｇｈｔｃｏｍｅｔ.Ｉｔｈａｓｂｅｅｎａｃｔｉｖｅｗｈｅｎｄｉｓｃｏｖ ｅｒｙａｔ 7ＡＵｆｒｏｍｔｈｅＳｕｎ(Ｓｅｋａｎｉｎａ ,1 996 ) .Ｔｈｅｌｏｃａｌｉｚｅｄｅｊｅｃｔｉｏｎｏｆｄｕｓｔａｎｄｇａｓｐｒｏｄｕｃｅｄｃｏｍ ｐｌｅｘｃｏｍａｓｔｒｕｃｔｕｒｅｔｈａｔｃａｎｂｅｕｓｅｄｔｏｓｔｕｄｙｔｈｅｅｊｅｃｔｉｏｎｓｐｅｅｄａｎｄｎｕｃｌｅｕｓｒｏｔａｔｉｏｎｐｅｒｉｏｄ .Ｆｕｒ ｔｈｅｒｍｏｒｅ…  相似文献   

SHRINKAGE OF THE ESTUARINE CHANNELS OF THE HAIHE DRAINAGE SYSTEM AND ITS INFLUENCES ON FLOOD HAZARD   总被引：2，自引：0，他引：2  

HU Shixiong  WANG Zhaoyin  DING Pingxing 《国际泥沙研究》1999,(2)

1INTRODUCTIONTheHaiheRiverBasinislocatedinNorthChinawithareaof262.6km2.Itisaquicklydevelopedareawithmanyimportantcitiesandindustrialhubs,includingBeding,Tianjin,Tangshan,Cangzhou,DezhouandHuanghua.Theareawatchedfastprogressesinurbanizationinthepastdecades,andhumanactivitieshaveresultedingreatinfluencesontheenvironment,riverhydrologyandsedimentbudget.Theareaisprojectedtobemoreprosperouswithmoreoilandgasfields,chemicalindustrybases,anddenserrailwaysandexpresshighwaysinthenextcent'Ury.T…  相似文献   

FROM YELLOW RIVER MODELS TO MODELING OF RIVERS     

Ben Chie YEN 《国际泥沙研究》1999,(2)

1INTRODUCTIONTheYellowRiverisadreamtoserioushydraulicengineerswholovechallenge.Historically,theriveristhe"sorrowofChina."Itisalsooneofthefirstriverssubjecttoscientificmodelingattheearlystageofdevelopmentofphysicalscalemodels.ThecontroversyearlythiscenturybetweenthemodelresultsofHubertEngels(1854-1945)andthoseofOt-toFranzius(1878-1936)effectivelydelayedtheChinesegovernment'sdecisiononhowtheriverwastoberegUlatedwithlevees.ChinahasalonghistoryofobservingandregulatingtheYellowRiver.There…  相似文献   

ECOLOGICAL CONSEQUENCES OF SOIL EROSION AND SEDIMENTATION     

Grace S. BRUSH 《国际泥沙研究》1999,(2)

IHISTORICALRECORDSSoilerosioniscloselyrelatedtorainfallandgreatlyenhancedbydeforestationforagricultUreandurbansuburbandevelopment.Amongtheeffectsofsoilerosionarethelossoftopsoilandaconsequentdecreaseincropproductivity.Erodedsoilisalsodepositedintoaquaticsystems,thuslesseningwaterqualityandleadingtodepletionoftheaquaticfoodresource.Italsocausessiltationofwaterwaysmakingthemineffectiveforcommercialtransportaswellasincreasingtheriskoffloods.Theimpactofsedimenterosionanddepositiononhumanso…  相似文献   

RESERVOIR SEDIMENTATION: RESEARCH NEEDS AND REFOCUSING PERSPECTIVES     

Rollin H. HOTCHKISS 《国际泥沙研究》1999,(2)

IINTRODUCTIONReservoirsedimentationisannuallydecreasingconstT[lctedworldwidewaterstoragebyanestimatedonepercent(Mahmood,1987).Lossesinaridregionsaredoubled,reducingtheaverageusefulreservoirlifeto20-30years(Bruk,1996).Atthisrateofstorageloss,hydroelectricityasanenergysourcecanhardlybecalledrenewable(Nordin,1993).Reservoirsaregenerallyfillingwithsedimentmorerapidlythananticipated.Forexample,datafromindiaindicatethataCtllalsedimentdeliveryishigherthanpredictedin24of27reservoirs,rangingfro…  相似文献   

BOULDERS ON THE MOVE: GEOMORPHIC HAZARDS FROM FLOODS AND DEBRIS FLOWS ALONG MOUNTAIN RIVERS   总被引：1，自引：0，他引：1  

Ellen E. WOHL 《国际泥沙研究》1999,(2)

IMOUNTAINE~ON-MENTSANDSEDIMENTGeologistsandgeomorphologistsareabletomakeatleasttWoimportantcontributionstomitigatinghazardsassociatedwithsedimentprocessessuchasfloodsordebrisflows.First,geomorphologistscaninterpretgeologicrecordsofthehiStoryofseddrientprocesses.Theserecordsmayprovideinsightintothemagnitude,frequency,andlocationofsedimentsourcesandtransport,aswellashillslopeandchannelresponsestosedimentprocesses.Informationonpastsedimentproductionandmovement,andchannelresponse,mayb'…  相似文献   

LAND USE CHANGE AND ITS DRIVING FORCES IN MINORITIES AREA     

Cai Kui 《云南地理环境研究》1999,(Z1)

１　ＢａｃｋｇｒｏｕｎｄＹｕｎｎａｎｉｓａｂｏｒｄｅｒｐｒｏｖｉｎｃｅｗｉｔｈ２５ｍｉｎｏｒｉｔｉｅｓｉｎｓｏｕｔｈｗｅｓｔＣｈｉｎａ,ａｎｄｍｏｒｅｔｈａｎ９４％ｔｅｒｒｉｔｏｒｙｉｓｍｏｕｎｔａｉｎａｒｅａ．Ｗｉｔｈｄｉｆｆｅｒｅｎｔｌｉｖｉｎｇｅｎｖｉｒｏｎｍｅｎｔａｎｄｈｉｓｔｏｒｉｅｓｏｆｍｏｖｉｎｇａｎｄｄｅｖｅｌｏｐｍｅｎｔ,ｅａｃｈｍｉｎｏｒｉｔｙｈａｄｆｏｒｍｅｄｉｔｓｏｗｎｌｉｖｉｎｇａｎｄｐｒｏｄｕｃｔｉｏｎｐａｔｔｅｒｎｓ,ａｎｄｔｈｅｓｅｃｈａｒａｃｔｅｒｓａｒｅａｌｓ…  相似文献   

构造的第三副面孔——地貌的构造分析   总被引：4，自引：0，他引：4  

G.F.Ufimtsev 《地学前缘》1995,2(1):0-0

地貌构造分析或叫新构造分析,是大地构造研究中最重要的领域。新构造学探讨地貌及相关的沉积特征,以阐明岩石圈近地表部分的新构造作用。由于Ｓ．Ｓ．Ｓｃｈｕｌｔｚ、Ｖ．Ａ．Ｏ－ｂｒｕｃｈｅｖ、Ｎ．Ｉ．Ｎｉｋｏｌａｅｖ、Ｎ．Ａ．Ｆｌｏｒｅｎｓｏｖ等人的工作,新构造学已作为一门独立的学科出现在苏联地学界。新构造学理论的基础是年轻内生作用的速率和特征与地球表面地貌的相关性。区域和应用新构造学研究的目的在于依据地貌资料编汇新构造图及进行各类地质预测。本文以中亚、东亚及整个地球为例进行了探讨。  相似文献   

基于有限断层动力学模型的逆断层—三维层状沉积盆地地震动模拟          下载免费PDF全文

(孟思博  金威  苗岳云  刘中宪) 《世界地震工程》2023,39(2):158-166

近断层效应使得沉积盆地对地震动放大效应更为复杂。本文针对逆断层发震下三维层状沉积盆地地震反应,基于波动谱元法,采用有限断层动力学模型,模拟断层动力破裂、地壳层地震波传播和层状沉积盆地对地震波散射全过程。在此基础上,对比分析了层状和均质沉积盆地对近断层地震动放大效应的影响,讨论了不同断层倾角下层状沉积盆地地震动加速度特性。结果表明：层状沉积盆地PGA空间分布与均质沉积盆地存在较大差异,由于近断层效应和盆地效应,层状沉积盆地地表局部范围竖向PGA大于水平向PGA;90°断层倾角下层状沉积盆地地表地震动放大范围与60°断层倾角结果明显不同,主要集中在盆地中心区域和断层附近,且幅值远小于60°断层倾角下结果;沿断层走向,盆地内地表地震动加速度峰值对应时刻较盆地外延后。  相似文献