简介：TheYushugouterrainofhigh-pressuregranulitefaciesinsouthernTianshanMountainiscomposedmainlyofanophiolitesuite.Mostselectedziroconsareroundorellipticalinshape,andsomeareoftetragonalprismwithroundedges.Thegranulometricanalysesshowthattheyarewellsortedinsedimentation.ZrO2/HfO2ratiosinzirconsrangefrom45to57.thesecharacters,togetherwiththepetrologicandgeochemicalcharactersofplagioclase-garnet-orthopyroxenitebearingzircons,indicatethattheprotolithofplagioclase-garnet-orthopyroxenitemaybederivedmainlyfromvolcanicbasesurgesedimentarydebrisinoceanicislandsandfromclaysformedbyseafloorweathering.Zirconsaresimplyofpyroclasticdebris.Theophioliteformationageof(440±18)Maandthefirst-stagemetamorphicage(amphiboliteorgranulitefacies)of(364±5)Mawereobtainedwithamethodofmultiplegrainsindifferentgroupsandamethodofconcordiaplot.TheseagesprovideimportantinformationonthetemporalandspatialoccurrenceofsouthernPaleoxoicTianshanOcean,Thesubductionrateoftheoceaniccrustandtheformationmechanismofophioliteofgranulitefacies.

简介：Wateristhemostactivecomponentinallgeologicalsystems.Ithasanimportanteffectonthephysicalpropertiesofmineralsandmelts.ItalsoplaysakeyroleintheevolutionoftheEarth.Accuratethermodynamicsdataonwaterarecurrentlyconfinedtopressuresbelow1.0GPaandtemperaturesbelow900℃.PresentedinthispaperarenewdataavailableontheP-Tpropertiesofwateratpressuresupto5.0GPa,develogedfromdifferentialthermalanalysisandultrasonicwaveamplitudeanalysis.Ithasbeenfoundthattheremayexistanotherternarypointat3.0GPaandthatultrasonicwaveamplitudechangeofice-watertransitionshowstwoinflectionpointsabove2.0GPa,consistentwiththetwopeaksofdifferentialthermalcurvesabove2.0GPa.Itmaybeanewphenomenonwhichneedsfurtherstudy.

简介：Huanghe河三角洲是世界的大河之一，自从最后，Huanghe河里的Huanghe河三角洲paleoenvironmental进化是一个热问题冰川。基于联合AMS14核心DYZK1沉积标明日期在的C在亚底部侧面上Huanghe河三角洲和声学的顺序沉没了，phytolith分析在96件沉积样品上被执行。谷物尺寸参数，磁性的危险性与biostratum的垂直变化被相结合重建在Huanghe河三角洲的paleo沉积、气候的条件。在索引参数有一条重要垂直变化法律的学习结果表演，和Huanghe河三角洲的那沉积环境经历了河的facies-sealand转变的进化进程外形潮汐的完全外形浅海的faciesdelta外形自从26.0kaB。P...phytolith分析结果如下。第一，phytoliths被划分成矛尖状，光滑伸长，多刺伸长，一种特殊格律，长矩形，bulliform和其它类型。在不同sedimental环境，phytolith内容定期变化，显示phytolith在沉积环境有的一样装配稳定性的某个度。第二，矛尖状，phytoliths的光滑伸长和多刺伸长范畴在潮汐的扁平的外形和三角洲免职有更大的内容，当时一在浅海的外形的更小的内容和河的外形环境。通过变化系数的比较分析，第三，在沉积的主要phytolith范畴的内容在sealand转变外形和河的外形免职有一个更大的变化振幅，当在tidalflat外形和三角洲外形免职是更稳定的时。

简介：Thehighstrengthlow-alloysteelsareweldedbyunderwaterwetweldingwithstainlesssteelelectrodes.Themicrostructuralandelectrochemicalcorrosionstudyofbasemetal(BM),weldzone(WZ)andheataffectedzone(HAZ)arecarriedouttounderstandtheinfluenceofthecorrosionproductlayergeneratedonthehighstrengthlow-alloysteelsweldedbyunderwaterwetweldingwithstainlesssteelelectrodes,methodsusedincluding,potentiodynamicpolarization,electrochemicalimpedancespectroscopy(EIS)andscanningelectronmicroscope(SEM).TheresultsindicatethattheWZactsasacathodeandthereisnocorrosionproductonitthroughouttheimmersionperiodinseawater.TheHAZandBMactsasanodes.ThecorrosionratesoftheHAZandBMchangewiththeimmersiontimeincreasing.Intheinitialimmersionperiod,theHAZhasthehighestcorrosionratebecauseithasacoarsetemperedmartensitestructureandtheBMexhibitesamicrostructurewithveryfinegrainsofferriteandpearlite.Afteraperiodofimmersion,theBMhasthehighestcorrosionrate.ThereasonisthatthecorrosionproductlayerontheHAZisdenseandhasabetterprotectivepropertywhilethatontheBMislooseandcannotinhibitthediffusionofoxygen.

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简介：Prestackreversetimemigration（RTM）isanaccurateimagingmethodofsubsurfacemedia.TheviscoacousticprestackRTMisofpracticalsignificancebecauseitconsiderstheviscosityofthesubsurfacemedia.OneofthestepsofRTMissolvingthewaveequationandextrapolatingthewavefieldforwardandbackward;therefore,solvingaccuratelyandefficientlythewaveequationaffectstheimagingresultsandtheefficiencyofRTM.Inthisstudy,weusetheoptimaltime-spacedomaindispersionhigh-orderfinite-difference（FD）methodtosolvetheviscoacousticwaveequation.Dispersionanalysisandnumericalsimulationsshowthattheoptimaltime-spacedomainFDmethodismoreaccurateandsuppressesthenumericaldispersion.Weusehybridabsorbingboundaryconditionstohandletheboundaryreflection.Wealsousesource-normalizedcross-correlationimagingconditionsformigrationandapplyLaplacefilteringtoremovethelow-frequencynoise.NumericalmodelingsuggeststhattheviscoacousticwaveequationRTMhashigherimagingresolutionthantheacousticwaveequationRTMwhentheviscosityofthesubsurfaceisconsidered.Inaddition,forthewavefieldextrapolation,weusetheadaptivevariable-lengthFDoperatortocalculatethespatialderivativesandimprovethecomputationalefficiencywithoutcompromisingtheaccuracyofthenumericalsolution.

简介：ThetimingoftheSouthAsianHigh(SAH)establishmentovertheIndochinaPeninsula(IP)fromApriltoMayanditsrelationstothesetupofthesubsequenttropicalAsiansummermonsoonandprecipitationovereastern-centralChinainsummerareinvestigatedbyusingNCEP/NCARdailyreanalysisdata,outgoinglongwaveradiation(OLR)dataandthedailyprecipitationdatafrom753weatherstationsinChina.ItisfoundthatthetransitionsofthezonalwindverticalshearandconvectionestablishmentovertropicalAsiaareearlier(later)intheyearsofearly(late)establishmentofSAH.Inthelowertroposphere,anti-cyclonic(cyclonic)anomalycirculationdominatestheequatorialIndianOcean.Correspondingly,thetropicalAsiansummermonsoonestablishesearlier(later).Furthermore,theatmosphericcirculationandthewatervaportransportintheyearsofadvancedSAHestablishmentaresignificantlydifferentfromthedelayedyearsinAsiainsummer.Out-of-phasedistributionofprecipitationineastern-centralChinawillappearwithaweak(strong)SAHandwesternPacificsubtropicalhigh,strong(weak)ascendingmotionintheareasouthofYangtzeRiverbutweak(strong)ascendingmotionintheareanorthofit,andcyclonic(anti-cyclonic)watervaporfluxanomalycirculationfromtheeastern-centralChinatowesternPacific.Accordingly,thetimingoftheSAHestablishmentattheupperlevelsofIPisindicativeofthesubsequentonsetofthetropicalAsiansummermonsoonandtheflood-droughtpatternovereastern-centralChinainsummer.

简介：TheprojectionofChina'snear-andlong-termfutureclimateisrevisitedwithanew-generationstatisticallydownscaleddataset,NEX-GDDP(NASAEarthExchangeGlobalDailyDownscaledProjections).Thisdatasetpresentsahigh-resolutionseamlessclimateprojectionfrom1950to2100bycombiningobservationsandGCMresults,andremarkablyimprovesCMIP5hindcastsandprojectionsfromlargescaletoregional-to-localscaleswithanunchangedlong-termtrend.Threeaspectsaresignificantlyimproved:(1)theclimatologyinthepastascomparedagainsttheobservations;(2)morereliablenear-andlong-termprojections,withamodifiedrangeofabsolutevalueandreducedinter-modelspreadascomparedtoCMIP5GCMs;and(3)muchaddedvalueatregional-to-localscalescomparedtoGCMoutputs.NEX-GDDPhasgreatpotentialtobecomeawidely-usedhigh-resolutiondatasetandabenchmarkofmodernclimatechangefordiverseearthsciencecommunities.

简介：Relativelyabundant17α(H)-diahopaneshavebeendetectedinthelowercretaceouslacustrinesourcerocksfromtheLishuFaultDepressionintheSongliaoBasinNortheastChina.Richlongchaintricyclicterpanes(carbonnumberuptoC35)andgammaceranehavebeenobservedinthosesourcerockswithrelativelyabundant17α(H)-diahopanes,whichisrarelyseeninpreviousreports.Inthispaper,theformationof17α(H)-diahopaneshasbeendiscussedfromthreeaspectsincludingmaturity,oxidation-reductionnatureofdepositionalenvironmentandparentmaterialcompositionbytheGC/MSanalyses.Theresultsrevealthatmaturityandoxidation-reductionnatureofdepositionalenvironmenthavelittleeffectontheformationof17α(H)-diahopanesintheinvestigatedarea.However,thepositivecorrelationbetweenlong-chaintricyclicterpanesand17α(H)-diahopanesarguesstronglyforacommonorigin,andtheoriginisrelatedtothealgaesinsalinewaterenvironment.Thealgaesinsalinewaterenvironmentmaybeakindoforiginof17α(H)-diahopanes.

简介：ByusingNCEP/NCARdailyreanalysisdataanddailyprecipitationdataof740stationsinChina,relationshipsbetweenthepositionvariationoftheWestPacificsubtropicalhigh(WPSH)andthediabaticheatingduringpersistentandintenserainsintheYangtze-HuaiheRiversbasinarestudied.TheresultsshowthatthepositionvariationofWPSHiscloselyassociatedwiththediabaticheating.Therearestrongapparentheatingsourcesandmoisturesinksinboththebasin(tothenorthofWPSH)andthenorthofBayofBengal(tothewestofWPSH)duringpersistentandintenserainevents.Inthebasin,Q1zbeginstoincrease3daysaheadofintenserainfall,maximizes2dayslaterandthenreducesgradually,butitchangeslittleafterprecipitationends,thuspreventingtheWPSHfrommovingnorthward.InthenorthofBayofBengal,2daysaheadofstrongrainfalloverthebasin,Q1zstartstoincreaseandpeaks1dayaftertherainoccurs,leadingtothewestwardextensionofWPSH.Afterwards,Q1zbeginsdecliningandtheWPSHmakesitseastwardretreataccordingly.Basedonthecompleteverticalvorticityequation,inmid-troposphere,theverticalvariationofheatinginthebasinisfavorabletotheincreaseofcyclonicvorticitynorthofWPSH,whichcounteractsthenorthwardmovementofWPSHandfavorsthepersistenceofrainbandsoverthebasin.TheverticalvariationofheatinginthenorthofBayofBengalisinfavoroftheincreaseofanti-cyclonicvorticitytothewestofWPSH,whichinducesthewestwardextensionofWPSH.

简介：High-velocityfrictionexperimentswereconductedonclayeyfaultgougecollectedfromHongkououtcropofBeichuanfault,locatedatthesouthwesternpartofLongmenshanfaultsystemthatcausedthedisastrous2008Wenchuanearthquake.Theultimatepurposeofthisstudyistoreproducethisearthquakebymodelingbasedonmeasuredfrictionalproperties.Drygougeofabout1mminthicknesswasdeformeddryatslipratesof0.01to1.3m/sandatnormalstressesof0.61to3.04MPa,usingarotary-shearhigh-velocityfrictionaltestingmachine.Thegougedisplaysslipweakeningbehaviorasinitialpeakfrictiondecaystowardssteady-statevaluesafteragivendisplacement.Bothpeakfrictionandsteady-statefrictionremainhighatslowslipratesareexaminedandgougeonlyexhibitsdramaticweakeningathighsliprates,withsteady-statefrictioncoefficientvaluesofabout0.1to0.2.Specificfractureenergyrangesfrom1to4MN/minourresultsandthisisofthesameorderasseismicallydeterminedvalues.LowfrictioncoefficientsmeasuredonexperimentalfaultsareinbroadagreementwithlackofthermalanomalyobservedfromtemperaturemeasurementsinWFSD-1drillhole(WenchuanEarthquakeFaultScientificDrillingProject),whichcanbeexplainedbyevensmallerfrictioncoefficientfortheWenchuanearthquakefault.High-velocityfrictionexperimentswithporewaterneedstobedonetoseeifevensmallerfrictionisattainedornot.Shinyslickensidesurfacesformathighsliprates,butnotatslowsliprates.Slipzonewithslickensidesurfacechangesitscolortodarkbrownandformsduplex-likemicrostructures,whicharesimilartothosemicrostructuresfoundinthefaultgougesfromtheHongkououtcrop.DetailedcomparisonsbetweenexperimentallydeformedgougesamplesandWFSDdrillcoresinthefuturewillrevealhowmuchwecouldreproducethedynamicweakeningprocessesinoperationinfaultzonesduringWenchuanearthquakeatpresent.

简介：当时，本地联合不稳定性将发生吸收边界状况和地波浪方程的数字计划允许精力自发地进入计算领域。也就是说，二个计划支持普通波浪解决方案，组速度指了进计算域。消除联合不稳定性的本地人的钥匙是避免如此的波浪答案。为块团在2D波导的P-SV波浪运动的有限元素模拟，为高顺序的稳定的实现的一条途径多播送的公式被提供。与一个一致矩形的网孔，它被证明并且验证那高周波的本地联合不稳定性能被设置等于或比\大的元素尺寸的比率消除(\sqrt2\)乘到S波浪速度的P波浪速度的比率。这些结果能为发另外的吸收边界条件导致的不稳定性问题是珍贵的。

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简介：Theproceduresofultrasonicextractionandclean-upwereoptimizedforthedeterminationofpolycyclicaromatichydrocarbons(PAHs)inmarinesediments.Sampleswereultrasonicallyextracted,andtheextractswerepurifiedwithaminiaturizedsilicagelchromatographiccolumnandanalyzedwithhighperformanceliquidchromatography(HPLC)withafluorescencedetector.Ultrasonicationwithmethanol-dichloromethane(2:1,v/v)mixturegavehigherextractionefficiencythanthatwithdichloromethane.Amongthethreeelutionsolventsusedinclean-upstep,dichloromethane-hexane(2:3,v/v)mixturewasthemostsatisfactory.Undertheoptimizedconditions,therecoveriesintherangeof54.82%to94.70%withRSDsof3.02%to23.22%foraspikedblank,andintherangeof61.20%to127.08%withRSDsof7.61%to26.93%foraspikedmatrix,wereobtainedforthe15PAHsstudied,whiletherecoveriesforaNISTstandardreferenceSRM1941bwereintherangeof50.79%to83.78%withRSDsof5.24%to21.38%.Thedetectionlimitswerebetween0.75ngL-1and10.99ngL-1fordifferentPAHs.AsamplefromtheJiaozhouBayareawasexaminedtotesttheestablishedmethods.

简介：在Quanji山岳的变形早Paleoproterozoicgranitoids，西北的中国为在TarimCraton和诺思中国Craton之间的关系提供限制。在granitoids底盘之中，Mohe石英闪长岩的岩石典型地显示出adakiticgeochemical特征，与中等K2O/Na2O比率(0.561.17)和高Sr(519619ppm)低Y(9.3720.40ppm)和Yb(0.971.77ppm)集中。岩石有在+2.4和+4.4和2.432.59Ga的弄空的披风Nd模型年龄之间的Nd(t)价值。magmatic锆石有积极Hf(t)价值从+0.40到+7.60和2.432.70Ga的弄空的披风Hf模型年龄，与在2.54和2.65Ga的主要山峰。geochemical和Nd-Hf同位素的特征显示Mohequartz-dioritic岩石可能被高压的变形少年的部分融化形成在在早Paleoproterozoic的post-orogenicextensional政体的外壳的岩石。它建议重要外壳的生长在2.4和2.52.7Ga发生在Quanji山岳和TarimCraton。Quanji山岳和TarimCraton可能在Neoarchean与北方中国Craton分享类似的外壳的进化历史。

简介：ThisstudyreportszirconU-PbandHfisotopesandwhole-rockelementaldataforgranodioritesfromtheEastKunlunorogen.ThezirconU-Pbdatingdefinestheircrystallizationageof235Ma.Therocksarecharacterizedbyhigh-Kcalc-alkaline,magnesianandmetaluminouswith（K2O+Na2O）=6.38wt.%–7.01wt.%,Mg#=42–50[Mg#=100×molarMg/（Mg+FeOT）],A/CNK=0.92–0.98,coupledwithhighεHf（t）valuesfrom-0.65to-1.80.Therockswerederivedfrompartialmeltingofajuvenilemaficcrustalsourcewithinnormalcrustthickness.Thejuvenilelowercrustwasgeneratedbymixinglithosphericmantle-derivedmelt（55%–60%）andsupracrustalmelt（40%–45%）duringtheseafloorsubduction.TogetherwithavailabledatafromtheEastKunlun,itisproposedthatthestudiedMiddleTriassicgranodioriteswereformedinpost-collisionalextensionsetting,inwhichmeltingofthejuvenilelowercrustinresponsetothebasalticmagmaunderplatingresultedintheproductionofhigh-Kgranodioriticmelts.

简介：NCEP/NCAR每日的分析数据和中国每日的gridded降水数据被用来学习在aprupt干旱洪水之间的关系转移中间低的活动范围在2011的长江和intraseasonal摆动(ISO；3060天)在中间高度的纬度在东亚上的上面的对流层的南方的循环。到洪水的从干旱的突然的转变发生在早6月。复杂实验直角的功能的开始的二个恢复领域证明从低纬度的向北方繁殖的westerlies在中间迟了的5月在长江(MLRYR)的中间低的活动范围上从高纬度与向南方繁殖的westerlies收敛。预定这集中在早中间的6月对应于洪水时期。ISO索引显著地并且断然在MLRYR上与降雨被相关。在干燥阶段期间(在转变前)，在MLRYR上的上面的对流层被气旋的流动描绘，在东方风，和集中。地区性的发行量被一列波浪火车在MLRYR上在湖贝加尔湖，在北中国上的反气旋，和气旋的东方上与气旋统治。在湿阶段期间，状况被颠倒。波浪火车的配置在干燥阶段期间赞成西的风骚乱的向南方的繁殖，当波浪火车的配置在MLRYR上在湿阶段期间赞成抽的效果和持续上升运动的发展和维护时。