非传统稳定同位素1历史与方法.docx
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非传统稳定同位素1历史与方法
非传统稳定同位素-1-历史与方法
中国地质科学院地质研究所INSTITUTEOFGEOLOGYCHINESEACADEMYOFGeologicalSCIENCES课程安排第一讲:
发展历史与分析方法,3学时第二讲:
铁同位素地球化学,6学时第三讲:
铜同位素地球化学,1.5学时第四讲:
锌同位素地球化学,1.5学时第五讲:
镁同位素地球化学,3学时第六讲:
应用实例,1.5学时第七讲:
总结,1.5学时1
中国地质科学院地质研究所INSTITUTEOFGEOLOGYCHINESEACADEMYOFGeologicalSCIENCES非传统稳定同位素地球化学朱祥坤(电话:
68999798;Email:
xiangkun@)中国地质科学院地质研究所中国科学院大学2
HistoryandTechniquesofNon-traditionalStableIsotopeAnalysisXiang-KunZhuInstituteofGeology,ChineseAcademyofGeologicalSciences
Traditional&Non-traditionalIsotopes?
Stableisotopes(e.gC,O,S)havebeenusedtoaddresssomemajorquestionsinEarthandsolarsystemsciencesoverthelastfewdecades:
–Climatechange,–Carboncycling,–Solarnebularprocessesandplanetformation.
SomeConcepts
Traditional&Non-traditionalIsotopes?
RecentadvancesinmassspectrometrymakeitpossibletoutiliseisotopevariationsofotherelementstoaddresssomeimportantissuesinEarthsciences.–Fe,Cu,Zn,Mo,etc.?
Non-traditionalstableisotopes
Traditional&Non-traditionalIsotopes?
Stableisotopes(e.gC,O,S)havebeenusedtoaddresssomemajorquestionsinEarthandsolarsystemsciencesoverthelastfewdecades?
TraditionalIsotopes
Traditional&Non-traditionalIsotopes?
Non-traditionalstableisotopes:
?
Li、Mg、Ca、Ti、V、Cr、Fe、Cu、Zn、Mo、etc.?
Thereisnocleardefinition?
Metalstableisotopes
WhyNon-traditionalIsotopes?
?
Geochemistry?
Cosmochemistry?
Biochemistry
WhyNon-traditionalIsotopes?
?
Geochemistry?
Metallogenesis:
Fe,Cu,Zn,etc.?
Redox(Reduction-Oxidation):
Fe,Cr,Mo,etc.?
Heavymetalpollution;Cr,Hg,Tl,etc.
WhyNon-traditionalIsotopes?
?
Cosmochemistry?
Condensationandevaporation?
Metalsegregation?
Redoxstate?
Nucleusynthesis
WhyNon-traditionalIsotopes?
?
Biochemistry?
Biologicallyutilised:
Fe,Cu,Zn,Mo,Ca,Mg,etc.
WhyNon-traditionalIsotopes?
?
Biochemistry?
Biologicallyutilised:
Fe,Cu,Zn,Mo,Ca,Mg,etc.?
Biosphere-Geosphereintereaction
WhyNon-traditionalIsotopes?
?
Biochemistry?
Biologicallyutilised:
Fe,Cu,Zn,Mo,Ca,Mg,etc.?
Biosphere-Geosphereintereaction
WhyNon-traditionalIsotopes?
?
Biochemistry?
Biologicallyutilised:
Fe,Cu,Zn,Mo,Ca,Mg,etc.
Elements&Isotopes
WhyNon-traditionalIsotopes?
?
Biochemistry?
Biologicallyutilised:
Fe,Cu,Zn,Mo,Ca,Mg,etc.?
Biosphere-Geosphereintereaction
Abriefhistory……TurningoftheCenturyNon-traditionalstableisotopegeochemistryPrehistory(Prelude)
Prehistory……?
Cuisotopes(Shieldsetal.,1965)?
Znisotopes(Blixetal.,1957;Rosman,1972)?
Feisotopes(Tayloretal.,1992)?
Noisotopicvariationsofnaturalmaterialshavebeendetected(ca.1%)
Prehistory……?
Liisotopes(Chan,1987);?
Bisotopes(SpivackandEdmond,1986;Xiaoetal.,1988)?
Caisotopes(Russelletal.,1977;Skulanetal.,1997)?
Slowdevelopments
Thebeginning……?
Europe:
–LyonGroup:
Cu,Zn–OxfordGroup:
Mg,Cu,Fe,Zn,Ti–BerneGroup:
Mo–ETH:
Tl,Fe
Thebeginning……?
USA:
–ClarkJohnsonGroup:
Fe–TomBullen(USGS):
Cr,Se–ArielAnbarGroup:
Mo
Thebeginning……?
中国(上世纪八十年代):
–中国地质科学:
Si、B(丁悌平等)–中科院盐湖所:
Li、B(肖银凯等)
Thebeginning……?
中国:
–国土资源部同位素地质重点实验室:
2003年建立非传统稳定同位素分析研究实验室MC-ICP-MS
Thebeginning……?
Fe,Cu,Zn,Mg,Mo等测试方法;?
相关标准物质?
同位素分馏研究?
环境、海洋、前寒武纪环境演化、地幔过程、研究作用、成矿作用、考古
Thebeginning……?
?
?
?
?
?
?
?
中国科学院地球化学研究所中国科学院广州地球化学研究所中国科学院地质与地球物理研究所西北大学南京大学中国地质大学(北京)中国地质大学(武汉)中国科技大学
Thebeginning……?
一批学者领域国外实验室开展研究;?
一批学者学成回国。
DS-TIMS
AstrobiologyUniquebiosignatures
FeisotopesareheavyenoughcannottobefractionatedinorganicallyButlightenoughtobefractionatedbiologically
Firstpaperfornon-traditionalstableisotopemeasurementsusingMC-ICPMSElement-doping
Firstreportfornon-traditionalstableisotopemeasurementsusingstandard-sample-bracketingtechniques
Constraintsonthehomogeneityoftheearlysolarnebula?
Thedegreeofchemical&isotopichomogeneityofthesolarnebulaisabasicissueinthestudyofsolarsystemevolution;?
Variationsinthreeormoreisotopesofanelementcanconstrainthisissue;
Elementsaresynthesizedinstarsdifferentstarsproduceelementswithdifferentproportionsofisotopes
Oxygenisotopeanomaliesinmeteoriticmaterials?
O-isotopeanomalieswidespreadinmeteoriticmaterials;?
Nucleosyntheticsignatures?
?
Chemicalreactions(MIF)?
Oxygenisotopeanomaliesinmeteoriticmaterials?
O-isotopeanomalieswidespreadinmeteoriticmaterials;?
Nucleosyntheticsignatures?
?
Chemicalreactions(MIF)?
?
Thiscorrelationisverysimple,butveryimportant.?
Itdemonstratesthatalltheanalysedterrestrialandextraterrestrialmaterialsareultimatelyfromasingleuniformsource.
Pallasite
Non-traditionalstableIsotopeGeochemistry,RMG55,2004《非传统稳定同位素地球化学的创建于发展》朱祥坤等,2013(6)《矿物岩石地球化学通报》《地学前缘》,2015年第5期
休息10Min
同位素质谱分析概述:
概念与原理朱祥坤国土资源部同位素地质实验室中国地质科学院地质研究所
Isotopes?
Isotopes:
nucleiwithsamenumberofprotonsbutdifferentmass;?
Radioactiveisotopes:
nucleitheyarenotstableanddecaytoothernuclei:
–238U→206Pb+8α–147Sm→143Nd+α
Isotopes?
Radiogenicisotopes:
nucleitheyarestableandaredecay-productsofradioactiveneclei:
–206Pb(daughterof238U)–143Nd(daughterof147Sm)
Isotopes?
Stableisotopes:
nucleitheyarestableandarenotdecay-productsofradioactiveneclei:
–12C,14N,16O;–24Mg,54Fe,63Cu,64Zn;
质谱法?
质谱法(MassSpectrometry):
是一种测量带电粒子质荷比的分析技术?
质荷比(mass-to-chargeratio):
带电粒子的质量与电荷比;?
44Ca+与88Sr2+具有相同的相同的质荷比,在质量谱图上占据相同的位置
Themassspectrumforboron质量谱图(massspectra)10B:
18.711B:
81.390Zr:
51.591Zr:
11.292Zr:
17.194Zr:
17.496Zr:
2.8
Cu
质谱法?
同位素分析?
原子量测定?
元素含量分析?
化合物鉴定?
化合物结构鉴定
质谱仪?
质谱仪(MassSpectrometer):
––––––热离子化质谱仪等离子体质谱仪气体质谱仪二次离子质谱仪加速器质谱仪飞行时间质谱仪
Electronimpact(EI)
Thermalionization(TIMS)?
Thermalionizationisusedforelementalorrefractorymaterials.?
Asampleisdepositedonametalribbon,suchasPtorRe,andanelectriccurrentheatsthemetaltoahightemperature.?
Theribbonisoftencoatedwithgraphitetoprovideareducingeffect.
Secondaryionization(SIMS)
PlasmaSource(ICPMS)?
Aplasmaisahot,partially-ionizedgasthateffectivelyexcitesandionizesatoms.?
Themostcommonplasmasourceisaninductively-coupledplasma
PlasmaSource(ICPMS)
Theionopticsintheion-sourcechamberofamassspectrometerextractandaccelerateionstoakineticenergygivenby:
K.E.=0.5mv2=zVwheremisthemassoftheion,visit'svelocity,eisthechargeoftheionandVistheappliedvoltageoftheionoptics.
mv2/r=Hevcentrifugal=centripetalforces.Whereristheradiusofcurvatureoftheionpath:
r=mv/eHmv2/r=Hev
mv2/r=Hevcentrifugal=centripetalforces.Whereristheradiusofcurvatureoftheionpath:
r=mv/eHmv2/r=Hev
DoubleFocusing
ElectrostaticAnalyserESA能量过滤(EnergyFiltering)
ElectronMultiplierTube
ElectronMultiplierTube
基本概念?
仪器质量分馏校正–线性法–指数法–幂法–标样-样品匹配法(standard-samplebracketing)
变量说明如内标同位素238U/235U=137.88?
定义Ruv=Mu/MvRuv=238U/235U?
定义Muv=Mu-MvMuv=238-235=4(两同位素的比值)(两同位素的质量数差)
线性分馏法则分馏因子β:
(用内标求)?
β=[(Ruv)N/(Ruv)m-1]/Muv(Ruv)N是内标值;(Ruv)m质谱测量值。
Muv=Mu-Mv?
校正公式为:
?
(Rij)c=(Rij)m×[1+Mij×β](Rij)c是校正值;(Rij)m质谱测量值Mij=Mi-Mj
幂分馏法则分馏因子β:
?
β=(Ruv)N/(Ruv)m]1/Muv-1(Ruv)N是内标值;(Ruv)m质谱测量值。
Muv=Mu-Mv?
校正公式为:
?
(Rij)c=(Rij)m×[1+β]Mij(Rij)c是校正值;(Rij)m质谱测量值Mij=Mi-Mj
指数分馏法则?
分馏因子β:
ln[(Ruv)N/(Ruv)m]?
?
[Mu/Mv](Ruv)N是内标值;(Ruv)m质谱测量值?
校正公式:
?
(Rij)c=(Rij)m×[Mi/Mj]β(Rij)c是校正值;(Rij)m质谱测量值MC-ICPMS常用
指数法则举例?
146Nd/144Nd=0.7219?
β=ln[(146Nd/144Nd)N/(146Nd/144Nd)m]/[146/144]=ln[(0.7219)/(146Nd/144Nd)m]/[146/144]校正?
(143Nd/144Nd)c=(143Nd/144Nd)m×[143/144]β(146Nd/144Nd)m和(143Nd/144Nd)m为测量值
信号干扰基质效应(Matrixeffects)同质异位素干扰(Isobaricinterference)
基质效应基质效应是指在一定的工作条件下,样品的电离效率和不同核素间的仪器质量歧视随样品成分的不同而改变;解决方案:
纯化;样品-标样匹配
同质异位素干扰同质异位素:
具有相同质荷比的不同离子或离子团;如:
87Rb+-87Sr+,44Ca+-88Sr2+,56Fe+-[40Ar16O]+解决方案:
纯化;高分辨
分辨率(massresolution)与分辨本领(massresolvingpower)
MassResolvingPower:
RP=m/dm
MassresolutionR=m/⊿m,inwhichmisthemassdifferencenecessarytoachieveavalleyof10%betweentwoneighboringpeaksofidenticalintensityatamassmandmassm+⊿m.
HighResolution
HighResolution
分辨本领(MassResolvingPower)isdefinedasm/dmWheremdesignatesthemassanddmthepeakwidthnecessaryforseparationatmassm.Aspecificm/zvalueandalsothemethodlike10%valleyor50%valleyorfullwidthathalfmaximum(FWHM)mustbegiven.
非传统稳定同位素分析技术概述朱祥坤国土资源部同位素地质实验室中国地质科学院地质研究所
Isotopicratiomeasurements?
Massspectrometry;?
Samplepurification
MC-ICP-MSNuPlasmaHR
高温等离子体,7000K,极高的电离效率;多个接收器对信号同时接收,获得高精度同位素比值;仪器的质量歧视相对稳定
MassdiscriminationcorrectionInstrumentalmassdiscrimination(Instrumentalmassbias,Instrumentalmassfractionation):
Heavyisotopegoesthroughmassspectrometerpreferentially.
指数分馏法则?
分馏因子β:
ln[(Ruv)N/(Ruv)m]?
?
[Mu/Mv](Ruv)N是内标值;(Ruv)m质谱测量值?
校正公式:
?
(Rij)c=(Rij)m×[Mi/Mj]β(Rij)c是校正值;(Rij)m质谱测量值MC-ICPMS常用
指数法则举例?
146Nd/144Nd=0.7219?
β=ln[(146Nd/144Nd)N/(146Nd/144Nd)m]/[146/144]=ln[(0.7219)/(146Nd/144Nd)m]/[146/144]校正?
(143Nd/144Nd)c=(143Nd/144Nd)m×[143/144]β(146Nd/144Nd)m和(143Nd/144Nd)m为测量值
MassdiscriminationcorrectionElement-DopingSample-Standard-BracketingDouble-spiking
MassdiscriminationcorrectionElement-Doping:
ZnforCuCuforZnTlforPbSimilarmass,Noisobaricinterference
指数分馏法则?
分馏因子β:
ln[(Ruv)N/(Ruv)m]?
?
[Mu/Mv](Ruv)N是内标值;(Ruv)m质谱测量值?
校正公式:
?
(Rij)c=(Rij)m×[Mi/Mj]β(Rij)c是校正值;(Rij)m质谱测量值MC-ICPMS常用
指数分馏法则?
分馏因子β:
ln[(Ruv)N/(Ruv)m]?
?
[Mu/Mv](Ruv)N是内标值;(Ruv)m质谱测量值?
校正公式:
?
(Rij)c=(Rij)m×[Mi/Mj]βThetrueisotopecompositionsofthedopant?
ElementdopingCombinationofSSBan