学科分类
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12 个结果
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  • 简介:Attheendof2015,athree-memberdelegationofyoungscholarsfromAlexanderGorchakovPublicDiplomacyFund(AGPDF)visitedBeijingandTianjinfromDecember7to11attheinvitationoftheChineseAssociationforInternationalUnderstanding(CAFIU).

  • 标签: delegation Tianjin INVITATION lasting visited EXCHANGES
  • 简介:TsogoVillageissituatedattheheadoftheBasumTsoinKongpoGyamdaCountyofNyingchiCityAccesstothelakeisonlypossiblebypassingthroughthisvillage,andabout40kilometerstothenorthcanonealsofindXingTsoLake,aplacejustbeggingforexploration.

  • 标签: COUNTY CITY EXPLORATION
  • 简介:Haze-to-fogtransformationduringalonglasting,lowvisibilityepisodewasexaminedusingtheobservationsfromacomprehensivefieldcampaignconductedinNanjing,Chinaduring4-9December2013.Inthisepisode,hazewastransformedintofogandthefoglastedfordozensofhours.Theimpactsofmeteorologicalfactorssuchaswind,temperature(T)andrelativehumidity(RH)onhaze,transitionandfogduringthisepisodewereinvestigated.Resultsrevealedsignificantdifferencesbetweenhazeandfogdays,duetotheirdifferentformationmechanisms.Comparisonwasmadeforboundary-layerconditionsduringhazydays,haze-to-fogdaysandfoggydays.DistributionsofwindspeedandwinddirectionaswellassynopticweatherconditionsaroundNanjinghaddeterminativeimpactsontheoccurrencesandcharacteristicsofhazeandfog.WeakenedsoutherlywindinsouthernNanjingresultedinhighconcentrationofpollutants,andhazeeventsoccurredfrequentlyduringthestudyperiod.Thewindspeedwaslessthan1ms-1inthehazeevent,whichresultedinastableatmosphericconditionandweakdispersionofthepollutants.Theheightofthetemperatureinversionwasabout400mduringtheperiod.Theinversionintensitywasweakandthetemperature-differencewas4℃km-1orlessinhaze,whiletheinversionwasstronger,andtemperature-differencewasabout6℃km-1,approachingtheinversionlayerintensityinthefogevent.HazeeventisstronglyinfluencedbyambientRH.RHvaluesincreased,whichresultedinhazedaysevidentlyincreased,suggestingthatanincreasingfractionofhazeeventsbecausedbyhygroscopicgrowthofaerosols,ratherthansimplybyhighaerosolloading.WhenRHwasabove90%,hazeaerosolsstartedtobetransformedfromhazetofog.Thisstudycallsformoreeffortstocontrolemissionstopreventhazeeventsintheregion.

  • 标签: HAZE FOG TRANSFORMATION METEOROLOGICAL elements
  • 简介:AbstractAnagedmalepatientwithcoronaryheartdiseasewhichhadbeentreatedwithcoronaryarterybypassgrafts(CABG)andadministrationofmetoprolol,presentedparoxysmalvertigointhepreviousthreeweeks.The24hourssynchronic12-leaddynamicelectrocardiography(DCG)revealedmanyepisodesofsinusarrestwhichmostlywerefollowedbyA-Vjunctionalorventricularescaperhythm,thelongestsinuspauselastingmorethan14.5secondswithnosymptom.Afterwithdrawalofmetoprolol,theDCGrevealedmuchlessepisodesofsinusarrestthanon-admission,butstillsomeA-Vjunctionalandventricularescapebeats.Sicksinussyndromeswasthendiagnosed,andasynchronousdual-chamberpacemaker(DDDR)wasimplantedtwoweeksafteradmission.

  • 标签: 心动过缓 动态心电图 起博器 心脏疾病
  • 简介:做Gd或做Lu的长晚霞红黄磷Y2O2S:Sm(3+)用高温度流动熔化方法被综合。获得的黄磷用X光检查衍射被分析决定晶体结构,并且阶段分析产品在单个阶段的表演。光系列和腐烂曲线在一个日立F-4500荧光分光光度计上被测量。腐烂时间在一个ST-900PM弱轻光度计上被决定。分析证明陆做的那位主人改进材料的光和腐烂时间。做的陆和Sm的集中被改变以便决定最佳的条件并且综合有最好的性质的产品。长晚霞的机制简短也被讨论。

  • 标签: 钇氧硫化物 长耐久性能 主体掺杂 稀土元素 光谱性质
  • 简介:Aseriesofnovelbluelong-lastingphosphorescencephosphorsSr6Al18Si2O37:Eu2+,RE3+(RE3+=Ho3+,Gd3+,Dy3+andPr3+)werepreparedbytheconventionalhigh-temperaturesolid-statereactioninareductiveatmosphere.TheirpropertiesweresystematicallyinvestigatedutilizingX-raydiffraction(XRD),photoluminescence,phosphorescenceandthermoluminescence(TL)spectra.ThephosphorsemittedbluelightthatwasrelatedtotheemissionofEu2+dueto5d-4ftransition.Brightbluelong-lastingphosphorescence(LLP)couldbeobservedaftertheexcitationsourcewasswitchedoff.Fortheoptimizedsample,thebluelong-lastingphosphorescencecouldlastfornearly4hinthelightperceptionofthedark-adaptedhumaneye(0.32mcd/m2).TheeffectsofRE3+ionsonphosphorescencepropertiesofthephosphorswerestudied,andtheresultsshowedthattheco-dopingofRE3+ionsgreatlyenhancedtheintensityofthepeakaround315Kwhichwasrelatedtothelonglastingphosphorescenceofthephosphorsatroomtemperatureandconsequentlyimprovedtheperformanceofthebluephosphorescencesuchasintensityandpersistenttime.

  • 标签: 荧光粉 长余辉 磷光 蓝色 发光特性 高温固相反应
  • 简介:Awhitelong-lastingphosphorCa2MgSi2O7:Dy3+waspreparedbythesolid-statereaction.Astrongbandpeakedat260nmwasshownintheexcitationspectrumof578nmemission,whichmightbeattributedtotheoxygendeficiencyofthehost.Afterirradiatedwith254nmfor4min,thewhiteafterglowofthesamplecouldbeseenfor3h.Moreover,thedepthsandfrequencyfactorsoftrapcenterswerecal-culatedfromthethermo-luminescencecurveofthesample,whichindicatedthatthetrapcenterscorrespondingtothe414Kbandweremorehelpfultothelong-lastingphosphorescence.

  • 标签: WHITE long-lasting phosphor SILICATE DYSPROSIUM THERMO-LUMINESCENCE
  • 简介:作为报导Y2O2S的改进:Tb3+,白光的长持续的黄磷:Y2O2S:Tb3+,Sm3+被准备由固态反应。光致发光系列证明在紫外刺激下面的Tb3+和Sm3+排出物的位置和形状在这位主人是类似的,它在不同刺激下面保证了一种稳定的白排放颜色(IEC的日光标准)。共同做的样品的腐烂曲线显示二个离子的排出物的腐烂时间是靠近的。热照明测量建议做的Sm3+离子创造的陷井是有用的推迟共同做的样品的白晚霞。因此,共同做的Sm3+离子的功能作为改进样品的白排放颜色并且充当新陷井中心被证实。

  • 标签: 白色 无机发光材料 稀土