简介:SurfaceO3concentrationanditsprecursorshavebeenobservedatLongfengshanstation,HeilongjiangProvinceforaperiodofoneyearfromAugust13,1994toJuly30,1995.RelationshipbetweensurfaceO3andthemeteorologicalconditionsduringthisperiodisanalyzedinthisstudy.ObservationresultsshowthatdiurnalvariationofsurfaceO3followsapatternofdouble-peakswithamplitudeof27—28ppbunderfinedaysinsummerandautumn.Althoughthediurnalvariationissmall(14ppb),itisstilldetectablewhenitisovercast.DiurnalvariationofO3isirregularunderrainydays.SurfaceO3concentrationriseswhenwindspeedstartstoincreaseat0800BT(BeijingTime)from0to6ms-1inautumn,winterandsummer.RelativehighsurfaceO3concentrationisnoticedfrequentlywhenS,SSW,SWandWSWwindareencounteredatthestationduringallseasons.At0800BTand1400BTthesurfaceO3concentrationincreaseswiththeincreaseofglobalradiationaccordinglyduringfinedaysinwinter,springandautumn.DuringfinedaysaveragepeakofO3concentrationinsummeris20ppbhigherthanthatinwinterwhiletheaveragepeakofglobalradiationinsummerisalmosttwiceashighasthatinwinter.TheaveragesurfaceO3concentrationunderfinedaysinautumnatLongfengshanstationis14ppblowerincomparisontotheobservationresultsfromLin’anstationwhereLin’anisataboutthesamelongitudeandlowerlatitude,withsameenvironment,whichismainlycausedbythedifferenceofglobalradiationduetodifferentlatitudesinthesetwoareas(differenceofaveragepeakglobalradiationabout100Wm-2).
简介:Distributionalfeaturesofδ18OinprecipitationinChinaZHANGXinpingDepartmentofGeography,HunanNormalUniversity,Changsha410081CHINA...
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简介:ThreesamplingcrosssectionsalongthesouthpathstartingfromtheTropicsthroughthevaporpassageintheYunnan-GuizhouPlateautothemiddle-lowreachesoftheYangtzeRiver,thenorthpathfromWestChina,viaNorthChina,toJapanunderthewesterlies,andtheplateaupathfromSouthAsiaovertheHimalayastothenorthernTibetanPlateau,aresetup,basedontheIAEA(InternationalAtomicEnergyAgency)/WMOglobalsurveynetworkandsamplingsitesontheTibetanPlateau.Thevariations,andtherelationshipwithprecipitationandtemperature,oftheδ18Oinprecipitationalongthethreecrosssectionsareanalyzedandcompared.Alongthesouthpath,theseasonaldifferencesofmeanδ18OinprecipitationaresmallatthestationslocatedintheTropics,butincreasemarkedlyfromBangkoktowardsthenorth,withtheδ18Ointherainyseasonsmallerthaninthedryseason.Theδ18Ovaluesinprecipitationfluctuateonthewhole,whichshowsthattherearedifferentvaporsources.Alongthenorthpath,theseasonaldifferencesofthemeanδ18OinprecipitationforthestationsinthewestofZhengzhouareallgreaterthanintheeastofZhengzhou.Duringthecoldhalfoftheyear,themeanδ18OinprecipitationreachesitsminimumatUrumqiwiththelowesttemperatureduetothewide,coldhighpressureoverMongolia,thenincreasesgraduallywithlongitude,andremainsatroughlythesamelevelatthestationseastwardfromZhengzhou.Duringthewarmhalfoftheyear,theδ18Ovaluesinprecipitationarelowerintheeastthaninthewest,markedlyinfluencedbythesummermonsoonoverEastAsia.Alongtheplateaupath,themeanδ18OvaluesinprecipitationintherainyseasonarecorrespondinglyhighinthesouthernpartsoftheIndiansubcontinent,andthendecreasegraduallywithlatitude.Asharpdepletionofthestableisotopiccompositionsinprecipitationtakesplaceduetotheverystrongrainoutofthestableisotopiccompositionsinvaporintheprocessofliftingoverthesouthernslopeo
简介:TheDiverGasRecoverySystem(DGRS)isanimportantaccessoryequipmentofthe300mSaturationDiveSystem.Thesystemfacilitatestherecyclingofthebreathinggasesfordivers,therefore,ithasgreateconomicbenefits.InApril1995,a300munmannedtestanda100mmannedtestontheHY2031DGRSwerecarriedoutsuccessively.Tenmonthslater,anothermannedtestontheHY2032DGRS
简介:一、地震基本参数表1 地震基本参数表发震时间年月日时分秒震 中 位 置微 观宏 观东经北纬东经北纬参考地名震级(MD)震源深度(Km)震中烈度 地震类型 199203030602228118°10′24°06′118°06′24°12′漳浦海外(厦门南)48Ⅴ孤立型 表1中宏观震中是根据陆地上勾划的等震线推测的,在微观震中的北西20公里左右。二、地震烈度分布本次地震的波及面很广,闽东南沿海地区均明显有感,调查在Ⅴ、Ⅳ度两个区内进行。由于地震影响场只有一小半在陆地上,勾勒出的是Ⅴ、Ⅳ度两条等震线的半椭圆弧线(见图14-1)。图14-1 1992年3月3日漳浦海外地震等震线图Ⅴ度区:震中位于海上
简介:研究了至今为止已发现的20个河外H2O超脉泽源的观测参数。多数河外H2O超脉泽源的光度在几十至几百个L⊙之内,但TXFS2226-184源的河外H2O超脉泽源光度达6100L⊙它属于射电星系类型,主要是由于其谱线轮廓较宽所造成的一种例外情况。所有20个河外H2O超脉泽源的系统速度约为几百到几千km·s^-1,16个河外H2O超脉泽源的峰值流量密度小于1Jy,但有4个河外H2O超脉泽源的峰值流量密度大于6Jy(6.2~16Jy)。通过对这些河外H2O超脉泽源的观测参数特征的分析和研究,得到这些观测参数之间的相关关系为:河外H2O超脉泽源的峰值流量密度的对数分别与系统速度的对数和距离的对数之间存在着反相关关系。而河外H2O超脉泽源的光度的对数与距离平方和峰值流量密度乘积的对数之间存在着正相关关系。
简介:之一:《自然危险(灾害)与社会》——ПPИPOДHbIEOПACHOCTИИOBЩECTBO《自然危险与社会》一书是6卷本的第一部。书中研究探讨了作为社会动荡根源的自然灾害出现的一般规律和基本趋势,研究了人口增长和全球气候变化对俄罗斯境内技术成因(人类经济活动)一自然危险(灾害)发育的影响。揭示了参数化法体系的基本原则,自然危险的一般分类法,自然危险出现后果的研究、预报和评价方法。本书着重论述自然危险的监测问题,除提出监测的要求外,还揭示了监测种类和方法、信息测量工作和信息管理子系统的结构和工艺规程。该书研究了自然风险的一般概念和风险的评价方法,危险自然作用和现象出现条件下居民、用地的管理和保护方法,消除紧急状况的救助和其他紧急救援工作的组织和手段,以及在实施自然安全领域保障国家政策的基本的,最迫切的方向。
简介:<正>所谓3S技术即GPS、GIS、RS技术。GPS(全球定位系统)是英文缩写词NAVSTAR/GPS(NAVigationSystemTimeAndRanging/GlobalPositioningSystem)的简称。全称应为“测时测距导航系统/全球定位系统”。GPS是由美国研制,并投入实际应用的最新卫星定位系统。其主要目的是为飞机和船舶导航定位。也可以用于其它多种目的。GPS技术已在航空、航天、航海、军事、地质、石油、勘探、交通、测绘等领域得到广泛的应用。美国于1993年6月26日已将GPS21颗卫星和3颗备用卫星全部发射入轨。