XRF和 ICP-MS测定风成沉积铜镍锌等 9种重金属元素的对比分析

Comparative Study of Nine Heavy Metal Elements Including Copper，Niccolum and Zincin Eolian Deposits Analyzedby XRFand ICP-MS

中文关键词:  重金属元素  XRF  风成沉积  黄土高原  青藏高原中图分类号: P595  P534.63文献标志码: A

英文关键词:Heavy metal element  X-ray fluorescence  Eolian deposits  Chinese Loess Plateau  Qinghai-XizangPlateau

中文摘要:

      风成沉积的重金属元素对生态环境变化具有指示意义，因此快速、准确地测定其含量显得特别重要。目前，主要通过 XRF(X射线荧光光谱)和 ICP-MS(电感耦合等离子体质谱)方法测定重金属元素的含量。文章对四个风成沉积剖面(黄土高原西峰剖面，青藏高原东北部种羊场剖面、泉吉河剖面、依毛剖面) 247件样品进行了 XRF和 ICP-MS分析，并对其中 9种重金属元素的含量进行了初步对比分析。结果表明: 1.Cu、Ni、Zn的 XRF测试结果和 ICP-MS测试结果高度一致(Pearson相关系数 r大于 0.84)。2.Co、Pb的 XRF测试结果和 ICP-MS测试结果在大多数剖面中具有较好的一致性，但在个别剖面中的一致性较差。 3.在种羊场和泉吉河剖面中， Th的 XRF测试结果比 ICP-MS的测试结果略低。两种方法测得的 As的含量在四个剖面中随深度的变化趋势高度一致； As的 XRF测试结果明显比 ICP-MS的测试结果低，差值可达 11.5μg/g(相对于 XRF法测定值的变化幅度达 214%)。 4.Cr和 T的 XRF测试结果高于 ICP-MS的测试结果，两种方法测得的 Cr含量的差值达 40μg/g。尽管 ICP-MS法具有比 XRF法更高的精度，但对于 Cu、Ni、Zn，采用高效廉价的 XRF法能得到与 ICP-MS法相媲美的测试结果。 5.西峰、种羊场剖面采用 XRF法测得的 Cu、Ni、Zn、As含量与磁化率呈现相似的变化，表明这些元素亦可指示风成沉积记录的气候环境变化。

英文摘要:

      Heavymetalelementsineoliandepositspreservealotofinformationaboutthesituationsofenvi-ronmentalpollutionand evenenvironmentalandclimaticchange.Thus，accurateand rapiddeterminationof heavy metal element contents in eolian deposits is essentialfor studying the above questions.To date，XRF(X-ray fluorescence spectrometry)and ICP-MS(inductively coupled plasma mass spectrometry)methods are mainly utilizedto determinethecontentofheavy metalelements in eoliandeposits. However，compara-tive analysis of the heavy metal elements in the eolian deposit samples analyzedby the above two methods isstill scarce. Here，weconductedXRFandICP-MS analyseson 247 samplesoffour typical eolian-deposit sections on the central Chinese Loess Plateau(XF section)and the northeastern Qinghai-Xizang Plateau(ZYC section，QJH section，andYM section). The contents of nine heavy metal elements including cop-per，niccolum and zinc were compared and discussed. The preliminary results show that:(1)Results of Cu，Ni，andZn analyzedbybothXRF andICP-MSmethods areofgoodconsistency，andthe variationsof Cu，Ni andZn contents measuredbyboth methods varying with the depth of the section are highly consis-tent(Pearson’scorrelation coefficient risgreaterthan 0.84).(2)VariationsofCoandPb analyzedbyboth methods are consistent in most studied sections，but there are inconsistencies in some sections.(3)In the ZYC andQJH sections，Thcontentsdeterminedbythe XRFare slightlylower than thosetestedbytheICP-MS method. The trend variations of arsenic(As)contents in four studied sections analyzed by both meth-ods highly consistent.Contents ofAs testedbythe XRF method are significantlylower than those tested bytheareICP-MS method，and the difference is up to about 11.5 μg/g，with changing amplitude of about 214% when compared with the measured value of XRF method.(4)Cr and T contents tested by the XRF method are higher than those determinedby the ICP-MS method；the difference ofCr content measuredby thetwomethodscanbeupto40μg/g.BecauseICP-MSmethodismoreprecisethanXRFmethod，theICP-MS method can be used to obtain more accurate results. However，for Cu，Ni，and Zn，the efficient and cheap XRF method can replace the ICP-MS method to obtain high-quality data.(5)The variations of Cu， Ni，Zn，As testedby the XRF method are similar to those of magnetic susceptibilityin the XF section and ZYC section，indicating that concentrations of these elements can also indicate the climatic and environ-mentalchangespreservedineoliandeposits.