简介：EDITOR’SNOTE:Longyearbyen,capitaloftheSvalbardIslands,entereditsannualprolongedperiodofdarknessonOctober9,2001.ThesunwasnotduetoriseagainuntilMarch8,2002.Duringthefive-month-longperiodofperpetualnight,peoplelivinginthenorthernmosthumansettlementseeonlystars,snowandice.Inthispartoftheworld,however,therearefourstudentsfromtheTibetAutonomousRegionjoint-ventureschool.

简介：

简介：Whippedup(激起)bystrongwinds,athickstormofchoking(令人窒息的)sandanddustturnedBeijing'sskiesfromgreytoyellowtoorangelastWednesday.

简介：<正>去西藏旅游,成了上海市民近来休闲的一大热点。青藏高原的特殊地理位置,更使一些户外旅游装备品牌备受关注。日前,上海港汇广场中厅,若置身于神秘的西藏。蔚蓝的天幕下,鲜艳的藏袍,洁白的哈达、高耸的布达拉宫……著名的户外品牌THENORTHFACE把品牌6周年庆典的路演现场搬进了商厦,再现出雪域高原的美丽图画。一批热衷于户外运动的爱好者被邀请来此,踏上THE

简介：Basedonthedataoftemperatureandsalinityofthe137°Esectioninthewintersandsummersfrom1967to1995,thegeo-strophiccurrentofthesectioniscalculatedandanalyzed,andthedriftingtracksofthesatellitetrackingdriftbuoydistributedonthe144°Esectionarealsoanalyzed.InlightofthesurfacedynamicheightdistributionintheCSKatlas,thispapercomparessomefeaturesoftheSubtropicalCountercurrent,theNorthEquatorialCurrentandtheNorthEquatorialCountercurrent.Themainresultsareasfollows:1.TheSubtropicalCountercurrent,theNorthEquatorialCurrentandtheNorthEquatorialCountercurrentarenotsimplesinglecurrents,buthavetwobranchesormore.Oneofthecommonfeaturesofthethreecurrentsmentionedaboveis"multi-branching"ofthecurrent.2.Thezonaldistributionoftheflowvelocitystructure,thealternateandintermittentoccurrenceoftheeastwardandwestwardflows,withashallowerflowlayerandbelongingtothesurfacefloworsubsurfacef

简介：TheGreekslegends,whichappearedontheParthiancoins,seemtobemeaninglessandconsiderasoneoftheambiguitiesinthehistoryofParthiandynasty.FromthebeginningoffirstcenturyAD,theGreekslegendappearedonParthianCoinsarevagueandonlyseemtobesymbolic.BytheinvasionofSakastothenorthofIranwhichledtoextinctionofthegoverningoftheGreeksinBactriaandpushedthembacktothenorthIndia,RomansfinallysucceededtoaddtheSeleucidasapartoftheirterritory,andleftthetradersinSeluciaandBabyloniainthewestandMargianaandBactriaontheeastunderdominationoflocalsratherthantheGreeks.InthisarticlewearetoinvestigateofdeclineofGreeksinBactriaanditsrelationtomeaninglessGreeklegendsonParthiancoins.

简介：UsingaDMT(DropletMeasurementTechnologies)continuousflowstreamwisethermalgradientcloudcondensationnuclei(CCN)countermountedonaCheyenneⅢAaircraft,about20flightsforaircraftmea-surementsofCCNoverNorthChinawereconductedintheautumnof2005andspringof2006.Accordingtothedesignforaircraftobservation,themethodofspiralascentordescentinthetropospherewasusedfortheverticalmeasurementofCCN,andsomecertainlevelswerechosenforhorizontalmeasurement.TheverticaldistributionsofCCNconcentrationsshowthatmostCCNparticlesareconcentratedinthelowleveloftroposphereandCCNconcentrationdecreasedwithheightincreasing.ItsuggeststhatthemainsourceofCCNisfromthesurface.Thisresultisconsistentwithformerstudiesduring1983-1985inChinawithastaticthermalgradientCCNcounter.ThecomparisonofverticalobservationsbetweenpollutedruralareanearShijiazhuangandnon-pollutedruralareanearZhangjiakoushowsthatthereisaboutfivetimesdifferenceinCCNconcentration.Butovertwopollutedcities,ShijiazhuangandHandan,thereisnonotabledifferenceinCCNconcentration.ThehorizontalflightmeasurementsforpenetratingthecumuluscloudsexperimentshowtheapparentdecreaseofCCNinclouds.ItconfirmsthatcloudhasadefiniteconsumptiveeffectonCCNparticlesbecausesomeCCNparticlescanformclouddroplets.ThesurfacemeasurementsofCCNinShijiazhuangCityweremadeduringJune-August2005.Thesta-tisticalCCNdatashowthegreatdifferenceinconcentrationatthesamesupersaturation(S)inShijiazhuangsummertime.TheminimumCCNconcentrationswere584,808,and2431cm~(-3),andthemaximumconcen-trationswere9495,16332,and21812cm~(-3)atS=0.1%,0.3%,and0.5%,respectively.CCNhasadiurnalvariationcycle.From0600BT,theconcentrationbegantoincreaseandreachedthemaximumataboutnoon.Thenitgenerallydecreasedthroughouttheafternoon.Thereasonmaybeisrelatedtotheonsetofemissionsfromvehiculartraffi

简介：

简介：I.TheDominoEffectsCausedbyGovernmentalChangeinTunisiaandEgyptMohamedBouazizi,a26-year-oldTunisianuniversitygradturnedstreetvendor,sethimselfonfireinhishomecityonDecember17th,2010inprotestoftheconfiscationofhiswaresandtheharassmentandhumiliationthatwasinflictedonhimbyamunicipalofficialandheraides.ThisincidentbecameacatalystforthegreatunrestandregionalchangesacrossmanycountriesintheMiddleEastandNorthAfrica.

简介：TNF希望每个中国人都有自己的“去野“梦想，在专业和大众两条线上引领更多人走出户外。

简介：

简介：

简介：

简介：TheFirstInternationalConferenceonGeoparkswasheldinBeijing,ChinainJune2004.AtthatconferencewewereimmersedintheUNESCOconceptofGeoparksforthefirsttime,AsNorthAmericans,wetakeforgrantednational.provincialandstateparkswhicharescatteredthroughoutthecontinentandproviderecreationalandeducationalopportunities.

简介：数字建模具有在理解地区性的地下水系统的行为的关键重要性。然而，当在长时间跨度上执行高分辨率的模拟时，为能力建模上的需求是集中的。这份报纸论述一个平行程序的应用程序加快在诺思中国平原地下水流动系统当模特儿详细说明。平行程序被在我们的并行计算的框架上重建著名MODFLOW程序实现，它被设计基于补丁的平行数据结构和算法，但是维持compute流动和MODFLOW的功能完成。有超过100万个格子和时间的一十年的详细模型被解决了。平行模拟结果对观察数据和这二个数据通常在好同意的地被检验。为在答案时间的比较，在32个核心上跑的平行程序比最快的基于MICCG的MODFLOW程序快6倍、比基于GMG的MODFLOW程序快11倍。因此，当使用平行程序时，显著计算时间能被节省，它便于在北方中国平原的快速的建模和地下水流动系统的预言。

简介：Basedonmeteorological,hydrological,forest,andgrasslanddatacollectedbylocationobservation,remotesensing,fieldsurveysandrelevantliteratureduring1956to2009,theecologicalenvironmentchangeinnorthernslopeoftheQilianshanMountainswasanalyzedsyntheticallyusingregressionandcorrelationanalyses.Theresultsshowedthatthetemperaturehadanannualvariationrateof0.0334℃·a-1innorthernslopeoftheQilianshanMountainssince1960,andexhibitedaraisingtrend,especiallysince1987.Theannualvariationrateofannualprecipitationwas0.5702mm·a-1,indicatingthattheprecipitationtendedtoincrease.Theclimatehadchangedfromaridtohumidinthisregionsince1976.From1956to2006,theglacierareaofsixinlandriverbasin（Shiyangheriver,Heiheriver,Beidaheriver,Shuleheriver,DangheriverandHalternheriver）andDatongheriverbasininnorthernslopeofQilianshanmountainsdecreasedby17.7%.Thicknessoftheglacierreducedabout5-20m,andthesnowlineroseabout100-140m.TheGlaciericereservesininlandriverbasinofHexidecreasedby11.4%.From1972to2007,27glaciersintheeasternsectionoftheQilianshanMountainsdisappeared.From1956to2009,therunoffchangeinthenorthernslopeoftheQilianshanMountainswasdifferentindifferentregions.TherunoffwasreducedsignificantlyinShiyangheriverbasin,increasedslightlyinHeiheriverbasin,andincreasedobviouslyinShuleheriverbasin.From1958to1988,theareaofdeforestationandfarmingwasmorethan10.0millionha,andtheforestareawasreduced0.6millionha.SincetheQilianshanMountainNatureReservewasestablishedin1989,theforestwasrestoringgraduallybecauseofcontinualprotectionandcultivating,andtheforestareawasincreased9.4millionhafrom1989to2008.Duetohumaninterference,especiallyover-grazingimpact,thequalityofthewood-land,shrub-landandgrass-landinnorthernslopeoftheQilianshanMountainswereinadegradedcondition,whichre

简介：

简介：

简介：

简介：ThecircumfluencearoundtheJiuduanSandbankisthoroughlystudiedbymeansoftheprinci-pleofleastresistanceinfluiddynamics.ThediversionratiooftheNorthChannelfor1998iscalculated,whichisalmostthesameasthefieldsurveydata.ThenormalandminimumdiversionratiosoftheNorthChannelafterstagesⅠ,ⅡandⅢregulationworksaswellasthefuturephaseareobtained.Thenumeri-calresultsandpredictedvalueareaccurate.