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简介：Sm-Ndisotopiccompositionsofeightlamprophyresamples,whichcomefromtheGezhengold-bearingshearzoneonwesternHainanIsland,aremeasured.TheSm-Ndisochronageis495.98±13.14Ma,(143Nd/144Nd)0=0.512094,εNd(t)rangesfrom+1.80to+2.00andTDMfrom982Mato1196Ma(average:1060Ma).Theauthorspointoutthatthewhole-rockSm-Ndisochronage(495.98±13.14Ma)reallyrepresentsthepetrogeneticageoflamprophyreandthetimeofmagmatismduringsubsequentsubduction.

简介：Ceriumisoneofmultivalentrearearthelements,whichcantransferfromtrivalencetotretavalenceatoxidizingenvironment.ThisprocessmaycausevariabledegreesoffractionationofCefromothertrivalentrearearthelements,andthusmayprovidespecificinsightintothegeologicalprocessesassociatedwithmarkedredoxomorphism.MultiplegeochemicaltracingofSr-Nd-CeisotopesareperformedonthefelsicandmaficintrusivesoftheNeoproterozoic(~800Ma)HuanglingcomplexlocatedattheeasternThreeGorges,SouthChina.TheintrusiverocksexclusivelyshowvariousextentsofnegativeCeanomalies.OntheεCe-εNdplot,mostsamplesfromthemaficintrusionsscatterwithinthesecondquadrant,whereasthosefromthefelsicintrusionswithinthefourthQuadrant.Bothofthetwogroupsexhibitrelativelylargerangeof?Ce(t)variationbutlimited?Nd(t)range,whichcauseadeviationfromthe'crustalarray'andrevealadecoupledNd-Ceisotopecorrelation.Theintermediate-felsicsuitehavevariedCe/Ce*ratiosbutbroadlyproximateεCe(t)values,indicatingthattheirnegativeCeanomaliesweregeneratedduringthemagmatism;onthecontrary,apositivecorrelationbetweenεCe(t)andCe/Ce*isobservedfortheintermediate-maficsuite,anindicationofanoriginofpost-magmaticalterationormetamorphismfortheirCeanomalies.Calculationofmodelage,theoccurrenceageofnegativeCeanomalies(TCe)fortheintermediate-maficsamplesinfersthatthealterationeventstookplace>350Ma.DatashowedthatnegativeCeanomaliesofthefelsicintrusionsmayreflectanincreaseofoxygenfugacityduringmagmaascending,ratherthananinheritancefromtheirsourcerocks.ThisexplanationimpliesthattheNeoproterozoicmagmatismoccurredatthecontinentalnucleusoftheYangtzeblockweredevelopingatageodynamiccontextofrapidlyregionaluplifting.

简介：蔡楚生执导的经典影片《渔光曲》曾在江、浙、沪三地取景,多地根据这一＂史实＂展开各自文脉传承和旅游宣传,其中个别提法还有待考证。本文通过挖掘原始资料,梳理出完整的影片拍摄行事历,证实影片在浙江的取景地为石浦、沈家门、普陀山,纠正了嵊泗拍摄一说。并对影片拷贝因保存不善而消失的内容作了推断,认为在舟山取景的画面可能在损坏之列。

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简介：高纯净的N2被用来在离子交换树脂的离子纯化期间增加活动阶段流动率。这被执行改进同位素分离和纯化的效率，并且满足快速的multiple-collector-inductively联合的血浆团spectrometry(MC-ICPMS)的效率要求分析。为Cu同位素分离，我们的结果以煤气的流动率显示了那>60mL/min，色析法的山峰拓宽了的分离和恢复率减少了到<99.2%。在另一方面，在Cu山峰的重要变化都没以20mL/min的煤气的流动率被观察，恢复率决心是>99.9%。Cu同位素比率，由标准样品的括方法测量了，同意了在内的引用数据一???牡浡?????????祳据牡潢慮整???????????????ò作？？

简介：西准噶尔庙尔沟岩体主要包括钾长石花岗岩、角闪二长花岗岩和花岗闪长岩．它们有着相似的同位素和微量元素地球化学特性．Ⅰsr(300Ma)=0．7040～0．7045．而εNd(T)=+6．6-+8．4．模式年龄(TDM)大约分布在0．37-0．62Ga时间上和早古生代岛弧建造和洋壳的形成时间大致吻合．庙尔沟地区后碰撞花岗岩的特征．反应其源区是来自亏损地幔．可能是早古生代期间形成的洋壳和岛弧建造．西准噶尔地区的基底是年轻的地壳，古老地壳即使有也非常有限．

简介：Shadong沉积物是在东方Tianshanorogenic带，和存款的地质的特征发现的第一大规模钨存款显示深深地隐藏的花岗石身体与矿化作用是遗传上相关的。从Shadong的锆石的LA-ICPMSU-Pb年龄隐藏了在这获得的花岗石研究是239湡瑩楯獤吗？？

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简介：Inthispaper,theforecastingequationsofa2nd-orderspace-timedifferentialremainderarededucedfromtheNavier-StokesprimitiveequationsandEulerianoperatorbyTaylor-seriesexpansion.Hereweintroduceacubicsplinenumericalmodel(SplineModelforshort),whichiswithaquasi-Lagrangiantime-splitintegrationschemeoffittingcubicspline/bicubicsurfacetoallphysicalvariablefieldsintheatmosphericequationsonsphericaldiscretelatitude-longitudemesh.Anewalgorithmof'fittingcubicspline—timestepintegration—fittingcubicspline—……'isdevelopedtodeterminetheirfirst-and2nd-orderderivativesandtheirupstreampointsfortimediscreteintegraltothegoverningequationsinSplineModel.AndthecubicsplinefunctionanditsmathematicalpolaritiesarealsodiscussedtounderstandtheSplineModel’smathematicalfoundationofnumericalanalysis.ItispointedoutthattheSplineModelhasmathematicallawsof'convergence'ofthecubicsplinefunctionscontractingtotheoriginalfunctionsaswellasits1st-orderand2nd-orderderivatives.The'optimality'ofthe2nd-orderderivativeofthecubicsplinefunctionsisoptimalapproximationtothatoftheoriginalfunctions.Inaddition,aHermitebicubicpatchisequivalenttooperateonagridfora2nd-orderderivativevariablefield.Besides,theslopesandcurvaturesofacentraldifferenceareidentifiedrespectively,withasmoothingcoefficientof1/3,three-pointsmoothingofthatofacubicspline.Thentheslopesandcurvaturesofacentraldifferencearecalculatedfromthesmoothingcoefficient1/3andthree-pointsmoothingofthatofacubicspline,respectively.Furthermore,aglobalsimulationcaseofadiabatic,non-frictionaland'incompressible'modelatmosphereisshownwiththequasi-LagrangiantimeintegrationbyusingaglobalSplineModel,whoseinitialconditioncomesfromtheNCEPreanalysisdata,alongwithquasi-uniformlatitude-longitudegridsandtheso-called'shallowatmosphere'Navier-Stokesprimitiveequationsinthes

简介：摘要：输电线路作为电力系统的关键组成部分，在雷电活动频繁的地区容易受到雷击影响，可能导致线路设备的损坏和系统的故障。为了提高输电线路的抗雷能力，本文针对雷电环境下的输电线路进行了防雷设计与雷电影响评估。对雷电击中概率、雷电流特性以及线路结构的分析，制定了合理的防雷措施，并基于数值模拟方法评估了这些措施对线路的保护效果。对于提高输电线路的可靠性和抗灾能力，减少雷击对电力系统的影响具有重要意义。

简介：摘要： 北京电影学院怀柔校区体育场主席看台屋盖采用两向格子型球面网壳，下部主体采用钢筋混凝土框架结构。采用midas Gen对屋盖结构进行静力分析、地震作用分析和稳定性分析，按三种半跨不利活荷布置对结构进行了验算，得到了结构在不同荷载组合工况下的应力和位移。结果表明，结构具有一定的安全储备，结构分析和构件设计均满足规范要求，为其他类似工程提供参考。

简介：Post-collisionalvolcanicrocksofMesozoicageoccurintheregionsadjacenttoGerze,partofthesouthernQiangtangTerraneofnorthernTibet,China.Geochronological,geochemical,andwholerockSr-Ndisotopicanalyseswereperformedonthevolcanicrockstobettercharacterizetheiremplacementageandmodelsfortheirorigin.Laserablation-inductivelycoupledplasma-massspectrometry(LA-ICP-MS)U-Pbzirconanalysesyieldedconsistentagesrangingfrom123.1±0.94Mato124.5±0.89Maforsixvolcanicrocksfromthestudyarea.Theintermediatevolcanicrocksbelongtothealkalineandsub-alkalinemagmaseriesintermsofK2O+Na2Ocontents(5.9%–9.0%),andtotheshoshoniticandcalc-alkalineseriesonthebasisoftheirhighK2Ocontents(1.4%–3.3%).TheGerzevolcanicrocksarecharacterizedbytheenrichmentoflightrareearthelements[(La/Yb)N=34.9–49.5]andlarge–ionlithophileelements(e.g.,Rb,Ba,Th,U,K,Pb,andSr),slightlynegativeEuanomalies(Eu/Eu*=0.19–0.24),andnegativeanomaliesinhighfieldstrengthelements(e.g.,Nb,Ta,HfandTi),relativetoprimitivemantle.Thesamplesshowslightlyelevated(87Sr/86Sr)ivaluesthatrangefrom0.7049to0.7057,andlowεNd(t)valuesfrom-0.89to-2.89.Theseresultssuggestthatthevolcanicrocksstudiedderivedfromacompositionallyheterogeneousmantlesourceandthattheirparentmagmaswerebasaltic.Themoremafic,parentalmagmastotheGerzevolcanicrockslikelyunderwentfractionalcrystallizationofclinopyroxene,hornblende,biotite,andpotassiumfeldspar,duringascent,withlittletonocrustalcontamination,priortotheireruption/emplacement.Whilethesevolcanicrocksexhibitgeochemicalsignaturestypicalofmagmasformedinadestructiveplate-marginsetting,itisplausiblethattheirmantlesourcemightalsohaveacquiredsuchcharacteristicsinanearlierepisodeofsubduction.