简介:Thegrowth,biochemicalcontentandbioaccumulationquantityof2,2’,4,4’-tetrabromodiphenylether(BDE-47)inSkeletonemacostatumwerestudiedunderdifferentN:Pratios(1,4,16,64and128).AllcellularbiochemicalcontentsofS.costatumpresenteddecreasingtrendovercultivationtime.Atearlystageofcultivation,thecellularprotein,carbohydrateandlipidinS.costatumpresentedhighervaluesintreatmentsofN:P=4and16.However,theywerelowerinthesetreatmentsatthelatestage,buthigherintreatmentsN:P=1and128.Similarly,BDE-47levelspercellofS.costatumwerehigherintreatmentsofN:P=4and16atearlystageofcultivation,whichwere3.8and3.7ng(106cells)-1,respectively.Atthemiddlestageofcultivation,theBDE-47levelperS.costatumcelllowered;anditfurtherreducedinthetreatmentsofN:P=4and16atthelatestagewiththevalues0.6and0.5ng(106cells)-1,respectively.However,itroseinN:P=128,reachingupto2.3ng(106cells)-1.ComparedwithBDE-47percell,BDE-47peralgalvolumeunderdifferentN:Pratiosdidnotpresentobviousdifference.ThequantityBDE-47accumulatedpercellofS.costatumwaspositivelycorrelatedwithprotein,carbohydrateandlipidpercell;meanwhile,theBDE-47pervolumehadapositivecorrelationwithbiochemicalcontentpervolume.ThevariationofbioaccumulationabilityofBDE-47inS.costatumcanbeexplainedbybiochemicalchangesduetoN:Pratios.
简介:利用中国科学院大气物理研究所北京325m气象塔气象要素和污染物浓度观测资料,采用气体干沉降阻力模型,对奥运会前后北京行政区内SO2和NO2的干沉降影响因子、干沉降速率、干沉降通量进行数值模拟。结果表明:1)随着大气稳定度、太阳辐射强度和下垫面类型的改变,北京SO2和NO2的干沉降速率有明显变化,表面阻力是影响气体干沉降速率变化的主要因子。2)SO2和NO2在白天的干沉降速率及通量普遍大于夜晚。3)静稳天气条件下,奥运会前北京地区一天可清除24tSO2和55.2tNO2,奥运会期间一天可清除10.8tSO2和50.4tNO2,这说明北京及周边地区的减排措施对改善奥运会期间的空气质量效果显著。
简介:Thetechniqueoncomputingthehorizontalpressuregradientforce(PGF)inRegCM2isimprovedwiththeerrorsubtractionmethod.Moreover,theregionalclimateinJuneof1991inChinaissimulatedbyemployingtheRegCM2.ComparisonwithotherschemesforcomputingthePGFshowsthattheerrorsubtractionmethodcaneffectivelyreducetheerrorofthePGF,improvethesimulationofwindsandalleviatethespuriousprecipitationinsteeptopographicareas.Furthermore,thesimulationofprecipitationinotherareasisinbetteraccordancewiththeobservation.
简介:TheNCARcommunityclimatemodelwasrunfor20yearsandthesimulatedEastAsianclimatewasanalyzedandcheckedagainsttheobservationdata.Itisfoundthatthelarge-scalefeaturesoftheEastAsiaclimateweresimulatedprettywellbythemodel,thoughtherearestillsomediscrepanciesbetweenthemodeloutputandtheobservation.Thesimulatedgeopotentialheight,windandtemperaturefieldsareveryclosetotheobservations.Thelargescalesystemssuchassubtropicalhigh.Mongoliahigh,IndianlowwhichhaveimportantinfluenceontheEastAsiamonsoonalsosimulatedprettywell.Itisalsofoundthatthemoisturefieldisnotsimulatedsowellasthosefieldsmentionedabove.Thesimulatedprecipitationisratherdifferentfromtheobservations.ThesesuggestthatsomephysicalprocessesintheCCM2needtobeimproved.
简介:TiO2filmswereformedonmetallictitaniumsubstratesbytheanodicoxidationmethodinH2SO4solutionunderthe80VD.C..PhasecomponentandmicrostructurewerecharacterizedbyX-raydiffraction(XRD)andscanningelectronmicroscopy(SEM).Watercontactanglesontitaniumoxidefilmsurfaceweremeasuredunderbothdarkandsunlightilluminationconditions.Corrosiontestswerecarriedoutinseawaterunderdifferentilluminationconditionsbyelectrochemistryimpedancespectrum(EIS)andpolarizationcurves.TheresultshowedthattheTiO2filmpreparedbytheanodicoxidationmethodwasanatasewithauniformstructureandwithoutobviousporesorcracksonitssurface.Theaveragewatercontactangleofthefilmwas116.4?indark,incontrasttoanangleof42.7?undertheUVilluminationfor2hours,whichdemonstratesgoodhydrophobicproperty.Theanti-corrosionbehavioroftheTiO2filmwasdecliningwiththeextendedimmersiontime.Underdarkconditions,however,thehydrophobicTiO2filmretardedthewaterinfiltratingintothesubstrate.Theimpedancechangedslowlyandthecorrosioncurrentdensitywas2ordersofmagnitudelowerthanthatwiththefilmilluminatedbysunlight.AllofthosementionedaboveindicatethattheTiO2filmpossessesmuchbetterperformanceunderdarkcondition,anditcanbeappliedasanengineeringmaterialunderdarkseawaterenvironment.
简介:最近,新大气的总环流大气环流当模特儿(GAMIL:国际机场LASG的格子点大气的模型)在大气的物理(国际机场)的研究所被开发了,中国科学院(CAS),它基于社区大气的模型版本2(CAM2)大气的研究(NCAR)的国家中心。自从二,模型有一样的物理过程但是不同动态核心,内部二个模型的年度可变性模拟表演被比较。整体途径被用来减少模型内部可变性。一般来说,二个模型的模拟表演是类似的。两个模型在模仿全部的时空可变性和南部的摆动索引有好性能。GAMIL比GAMIL的内部可变性有的CAM2,和模型在东方亚洲冬季发行量模拟更好表现对比CAM2的外部强迫的更好的回答。这些显示动态核心的改进是很重要的。比在低纬度在中间和高纬度有更少的可预测性,这也被验证。
简介:Aseriesofidealizedmodelsimulationsareanalyzedtodeterminethesensitivityofmodelresultstodifferentconfigurationsofthelateralboundaryconditions(LBCs)insimulatingmesoscaleshallowconvectionoverhillyterrain.Inthesimulationswithsteadythermalforcingatthemodelsurface,aradiationconditionatbothboundariesisthebestchoiceunderhighwindconditions,andthebestresultsareproducedwhenboththenormalvelocitiesandthetemperaturearetreatedwiththeradiationschemeinwhichthephasespeedisthesamefordifferentvariables.Whenthebackgroundwindspeedisreasonablysmall,theLBCconfigurationwitheithertheradiationorthezerogradientconditionatbothboundariestendstomakethenumericalsolutionunstable.Thechoiceofaconstantconditionattheinflowboundaryandaradiationoutflowboundaryconditionisappropriateinmostcases.Inthesimulationswithdiurnalthermalforcingatthemodelsurface,differentLBCschemesarecombinedtogethertoreducespurioussignalsinducedbytheoutflowboundary.Aspecificationinflowboundarycondition,inwhichthevelocityfieldsattheinflowboundaryareprovidedusingthetime-dependentresultsofasimulationwithperiodicLBCsoveraflatdomain,istestedandtheresultsindicatethatthespecificationconditionattheinflowboundarymakesitpossibletouseasmallermodeldomaintoobtainreasonableresults.Themodelhorizontaldomainlengthshouldbegreaterthanacriticallength,whichdependsonthedomaindepthHandtheanglebetweengravitywavephaselinesandthevertical.Anestimateofminimumdomainlengthisgivenby[(H-zi)/πU]√N2L2x-4π2U2,whereNandUarethebackgroundstabilityandwindspeed,respectively,Lxisthetypicalgravitywavelengthscale,andziistheconvectiveboundarylayer(CBL)depth.
简介:ProcessofsourcedynamicsoftheJingtaiearthquake(M=6.2)Xue-BinDU(杜学彬);Zhi-DeYAN(闫志德)andMing-WuZOU(邹明武)(EarthquakeResearchInstitu...
简介:SongkeWellNo.2,oneofthemainpartofthescientificdrillingprojectinSongliaoBasin,whichwasdrilled7018mandacquiredthepartofcorescontinuouslyfromtheLowCretaceoustotheCarboniferousandthePermianfromthe2843mdeep,canbeconsideredasthedeepestcontinentaldrillingprojectinAsia.Aimingatthefeaturesoflongerwellsections,largerdiametersandmultiplespud-insforcoringofSongkeWellNo.2,thisprojectbrokethroughthe"coringinsmalldiameterandreaminginlargediameter"spud-indrilling-completionprocedureswhicharealwaysusedinlarge-diameter-wellcoringforcontinentalscientificdrillingprojectsindomesticandoverseasandthedrillingmethodofshort-singlecylinderroundtripfootage.Atthesametime,"coringinthesamediameterandcompletingdrillingatonesinglediameter"wasachievedatallφ311mmandφ216mmcoringsectionsofmorethanonethousandmeterslong,high-efficientoperationwith"drillinglongfootagewithdrilltoolscombinedinmulticylinders"wasachievedatdeepcoringsection.Fourworlddrillingrecordswerecreatedwhichincludemorethanathousandmeterscontinuouscoringatφ311mm,andthefootageperroundtripfootageatφ311mm,φ216mmandφ152mmisallmorethan30m,allofthesebreakthroughsreducedatleast300daysforthisproject;moreover,consideringthecharacteristicsofformationsthatthegeothermalgradientishighinthedrilledsectionsandtheinside-welltemperatureisover240℃afterdrillingcompletion,aformate-polymerwater-basedmudsystemwasdevelopedbycompoundingattapulgiteandsodiumbentoniteandbyaddingindependentlydevelopedhigh-temperaturestabilizer,whichcanprovidecriticaltechnicalsupportforsuccessfulwellcompletionat7018minthesuper-high-temperatureenvironmentItisthefirsttimethatthewater-basedmudisoperatedattheworkingtemperaturehigherthan240℃inChina;Besides,consideringthehigh-qualityrequirementoncoresimposedbytheproject,themethod"mechanicalcor