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1.
采用丹宁棉对地质样品溶液中的铌、钽、锆、铪进行分离富集,将写信后的丹宁棉在600℃灼烧30min,灰分用发射光谱法同时测定四元素。检出限与通常的发射光谱法相比降低约2个数量级,经国家级标准物质检验,结果与标准值相符,精密度试验,各元素的RSD(n=20)为2.6%-7.9%。  相似文献   

2.
采用粉末压片法制样,选用标准样品,以经验α系数和散射线内标法校正基体效应和元素谱线重叠干扰,使用ZSXPrimusⅡX射线荧光光谱仪对一般地质样品中的铌、钽、锆、铪、铈、镓、钪、铀等稀有元素进行测定,分析结果与标准值和参考值吻合,12次测定的相对标准偏差(RSD)小于10%。  相似文献   

3.
Isotope dilution determinations of Lu, Hf, Zr, Ta and W are reported for nine test portions (five for W) of NIST SRM 610 and 612 glass wafers. Additionally, all test portions were analysed for their Hf isotope compositions. In general, high field strength elemental (HFSE) distributions in NIST SRM 610 and 612 were reproducible to ~± 1%, except for Zr (± 5%) in NIST SRM 612, and absolute reported concentrations agreed with previously published values, but with higher precision. The slightly worse reproducibility of Zr in NIST SRM 612 compared to other HFSE is interpreted to result from analytical scatter, rather than sample inhomogeneity. The analyses demonstrated elemental homogeneity for both glass wafers for samples of 1–2 mg with respect to the precision of the method, i.e., ± 1% or better. Average Hf isotope compositions for both glass wafers agreed within uncertainty and the weighted average of all determinations yielded a mean 176Hf/177Hf ratio of 0.282111 ± 0.000009 (95% confidence level). However, although mean values for NIST SRM 610 and 612 agreed within analytical limits, NIST SRM 610 test portions showed a tendency of systematically elevated isotope composition of ~ 0.5 ?Hf units when compared to NIST SRM 612, which may indicate a slightly more radiogenic Hf isotope composition of NIST SRM 610. The results of this study suggest that NIST SRM 610 and 612 are valuable calibrators for HFSE in situ analyses within the given uncertainties.  相似文献   

4.
We have developed a rapid and accurate method to determine Zr, Nb, Hf and Ta (denoted as HFSE) in geological samples by inductively coupled plasma-mass spectrometry fitted with a flow injection system (FI-ICP-MS). The method involves sample decomposition by HF followed by HF dissolution of HFSE coprecipitated with insoluble M and Ca fluoride residues formed during the initial HF attack. This HF solution was directly nebulized into an ICP mass spectrometer. An external calibration curve method and an isotope dilution method (ID) were applied for the determination of Nb and Ta, and of Zr and Hf, respectively. Recovery yields of HFSE were > 96% for peridotite, basalt and andesite compositions, apart from Zr and Hf for peridotite (> 85%). No matrix effects for either signal intensities of HFSE or isotope ratios of Zr and Hf were observed in basalt, andesite and peridotite solutions down to a dilution factor of 100. Detection limits in silicate rocks were 40, 2, 1 and 0.1 ng g-1 for Zr, Nb, Hf and Ta, respectively. This technique required only 0.1 ml of sample solution, and thus is suitable for analysing small and/or precious samples such as meteorites, mantle peridotites and their mineral separates. We also present newly determined data for the Zr, Nb, Hf and Ta concentrations in USGS silicate reference materials DTS-1, PCC-1, BCR-1, BHVO-1 and AGV-1, GSJ reference materials JB-1, -2, -3, JA-1, -2 and -3, and the Smithsonian reference Allende powder.  相似文献   

5.
采用低压聚乙烯镶边垫底的粉末样品压片制样,用ARL ADVANT’XP+型X射线荧光光谱仪对土壤和水系沉积物样品中C、N、Na2O、MgO、Al2O3、SiO2、P、S、Cl、K2O、CaO、Sc、Ti、V、Cr、Mn、Fe、Co、Ni、Cu、Zn、Ga、Nb、Zr、Y、Sr、Rb、Pb、Th、Ba、As、Br、Hf、La、Ce和Nd等36个组分进行测定。重点研究了C、N等元素的测定务件和痕量元素的背景选择和谱线重叠校正问题。使用经验系数法和康普敦散射作内标校正基体效应。经标准物质校验,结果与标准值吻合。方法的检出限、精密度和准确度能满足多目标地球化学调查样品的分析要求。用GBW 07404土壤国家标准物质进行测试,12次重复测定的精密度(RSD),除N和Cl〈11.0%,其余各组分均〈6.0%。  相似文献   

6.
To assess the homogeneity of and provide the first Sr‐Nd‐Hf‐Pb isotopic reference values for the Chinese Geological Standard Glasses CGSG‐1, CGSG‐2, CGSG‐4 and CGSG‐5, we measured these isotopes in several measurement sessions over the course of nearly 3 years. The results were obtained by high‐precision MC‐ICP‐MS and TIMS. Our investigation indicates that these CGSG glass reference materials are homogenous with regard to Sr‐Nd‐Hf‐Pb isotopic distribution and are therefore suitable geochemical materials for Sr‐Nd‐Hf‐Pb isotope measurements. Clear differences in Sr‐Nd‐Hf‐Pb isotopic composition were observed between the glasses and the original powdered rock reference materials (CGSG‐2 and GSR‐7, and especially CGSG‐5 and GSR‐2) because of flux addition during preparation of the glasses. The new Sr‐Nd‐Hf‐Pb isotope data provided here might be useful to the geochemical community for in situ and bulk analysis.  相似文献   

7.
灰尘中主次量元素的X射线荧光光谱分析   总被引:1,自引:0,他引:1  
采用粉末压片-X射线荧光光谱法对灰尘样品中P、Ti、V、Ni、Cu、Zn、Ga、Rb、Sr、Nb、Cs、Ba、La、Hf、Zr、Pb、Al2O3、CaO、Fe2O3、K2O、MgO、Na2O、SiO2等主次量组分进行测定。探讨了谱线校正,使用经验系数法和康普顿散射线作内标校正基体效应。用国家一级标准物质进行验证,测定值与标准值相符。  相似文献   

8.
We report new data for thirty seven elements determined in twenty six Chinese geochemistry reference materials using inductively coupled plasma-mass spectrometry and a reliable and simple dissolution technique. One hundred milligrams of sample were digested with 1 ml of HF and 0.5 ml of HNO3 in PTFE-lined stainless steel bombs heated to 200 °C for 12 hours. Insoluble residues were dissolved using 6 ml of 40% v/v HNO3 heated to 140 C for 3 hours. Analytical calibration was accomplished using aqueous standard solutions. Rhodium was used as an internal standard to correct for matrix effects and instrument drift. Precisions were typically better than 5% RSD. Most of the data presented here agree well with the published certified values. For the elements Zr, Hf and most other trace elements, the measured values were less than 10% in error when compared to certified values.  相似文献   

9.
采用低压聚乙烯镶边垫底的粉末样品压片制样,用PW2440X射线荧光光谱仪对多目标地球化学调查样品中Na2O、MgO、Al2O3、SiO2、P、K2O、CaO、Ti、Mn、Fe2O3、Co、Nb、Zr、Y、Sr、Rb、Pb、Th、Zn、Cu、Ni、V、Cr、Ba、La等组分进行测定。重点讨论了微量元素的背景选择和谱线重叠校正问题。使用经验系数法和康普顿散射线作内标校正基体效应,经标准物质分析检验,结果与标准值吻合,用GBW07308和GBW07310水系沉积物国家一级标准物质作精密度试验,统计结果RSD(n=12)除La、Cr、Co和Th<14.00%以外,其余各组分均小于6.00%。  相似文献   

10.
This paper presents data on REE and Y, Nb, Zr, Hf, Ta, Th and U abundances for two candidate reference materials (RMs), spinel lherzolite LSHC-1 and amphibole Amf-1, being currently developed at the Institute of Geochemistry SB RAS, Irkutsk. To determine the contents of these elements inductively coupled plasma-mass spectrometry was applied with: (i) solution nebulisation (solution ICP-MS) and (ii) laser ablation (LA-ICP-MS) of fused glass disks. The precision of results obtained by both techniques was better than 6% RSD for most elements. Accuracy was assessed by using the geochemical RMs JB-2, JGb-1 (GSJ) and MAG-1 (USGS). The trace element results by solution ICP-MS for JGb-1 and JB-2 agree with reference values presented by Imai et al. (1995, this Journal) within 1–10%. Significant differences were found for Nb and Ta determinations. The accuracy of LA-ICP-MS results evaluated by RM MAG-1 was within 4%, except for Eu (about 10%). The analytical results obtained for LSHC-1 and Amf-1 by solution ICP-MS and LA-ICP-MS were in good agreement with each other and with INAA and XRF data presented for the certification of these RMs. They can be considered as the indicative values for assigning certified values to the above-mentioned RMs.  相似文献   

11.
Results are presented of the determination of Zr, Nb, Hf and Ta in 74 standard reference materials by inductively coupled plasma mass spectrometry (ICP-MS). Samples are decomposed by fusion with lithium metaborate and the analytes are separated prior to analysis by precipitation of their cupferrates. Calibration is made using synthetic solutions and internal standardization with Ru (for Zr and Nb) and Re (for Hf and Ta). Accuracy is assessed by comparison with recommended values and precision is evaluated by replicate analyses of five SRMs.  相似文献   

12.
目前土壤中Se主要采用原子荧光光谱法测定,存在用酸量大、前处理相对复杂等缺点,对于高含量Se的测定则需要高倍稀释,无疑会扩大分析误差.本文采用粉末压片波谱-能谱复合X射线荧光光谱法测定湖北富硒土壤样品中的Se等17个主次量元素,波谱分析10个元素的同时,能谱分析As、Cu、Rb、Sr、Zr、Ba、Ni等7个元素,大幅节...  相似文献   

13.
The National Research Council (NRC), Ottawa, Canada sandy marine sediment reference material HISS-1 was characterised for thirty-seven trace elements by neutron activation optimised irradiation, cooling and counting protocols using the low power Miniature Neutron Source Reactor (MNSR) as a neutron source. This INAA methodology quantified twenty additional elements including ten rare earth (Ce, Dy, Eu, Ho, La, Lu, Nd, Sm, Tb and Yb) and ten other elements (Ba, Br, Cs, Ga, Hf, Rb, Sc, Ta, Th and Zr) missing in the final NRCC certification. A large number of values produced by different irradiation schemes together with the use of certified reference materials in the quantification step that showed good precision, provided confidence in the results. The reliability of the REE data was checked by plotting chondrite-normalised graphs.  相似文献   

14.
A voltammetric method for the determination of the high field‐strength elements Ti, Zr, Hf, Nb and Ta by adsorptive stripping of their tartrate complexes is presented. The applicability of the method to geological and metallurgical samples is illustrated by the analysis of certified reference materials (USGS BCR‐2 basalt, BCS‐CRM 388 zircon and Euronorm CRM 579‐1 ferroniobium). Suitable sample preparation techniques, involving fusion with LiBO2 and acidic and basic fluxes, followed by preliminary separation by anion chromatography are described. The method is rapid, affordable and environmentally friendly as it does not require problematic compounds such as hydrofluoric acid or toxic solvents and represents an alternative to more commonly used methods (AAS, ICP‐OES, ICP‐MS).  相似文献   

15.
本文采用先螯合后吸着的方法,研究了XO螯合形成纤维分离富集微量锆铪的性能。试验研究表明,该纤维能富集浓度低至0.04ppm的锆铪,并且能与大量基体元素相分离;当锆铪总量约为0.41ppm时,采用本方法九次测定的标准偏差为0.21,变异系数为1.05%;回收率可达99.24%。该方法具有操作简便、交换速率快、干扰少、富集能力强、成本低等特点,适用于成分较复杂样品中微量锆铪的分离和富集。  相似文献   

16.
The concentrations of fifty trace elements, including relatively volatile elements and transition metal elements, in fused glasses of Geological Survey of Japan rock reference materials GSJ JR-2, JA-1, JA-2, JB-1a, JB-3, JGb-1 and JF-1 were determined by particle (proton) induced X-ray emission (PIXE) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). The fused glasses were prepared by rapid fusion and subsequent quenching in welded platinum capsules and were found to be homogeneous for major elements and for trace elements with concentrations of more than 1 μg g-1 within the observed precision (± 10% mean) on a 70 μm sampling scale. The values obtained by PIXE and LA-ICP-MS for the transition elements (Cr, Mn, Fe, Ni and Cu), the relatively volatile elements (Zn, Ga, Rb and Pb) and the refractory elements (Y, Zr, Nb and Th) with concentrations greater than a few μg g-1 showed good agreement (within 10 % relative difference). The values for almost all the elements detected at concentrations higher than 1 μg g-1 as determined by LA-ICP-MS also agreed well with the reference values (mean relative difference < ± 10%), except for B and Cu. The good agreement confirmed the appropriateness of the NIST SRM 600 series glass calibration reference material for LA-ICP-MS analysis of glasses with variable major-element compositions for almost all elements. The concentrations of Cu in all the samples were lower than the reference values, which was attributed to adsorption of the transition metals onto the platinum capsule during preparation.  相似文献   

17.
A simple, rapid and precise method is described for determining trace elements by laser ablation (LA)-ICP-MS analysis in bulk geological materials that have been prepared as lithium borate glasses following standard procedures for XRF analysis. This approach reliably achieves complete sample digestion and provides for complementary XRF and LA-ICP-MS analysis of a full suite of major and trace elements from a single sample preparation. Highly precise analysis is enabled by rastering an ArF excimer laser (λ= 193nm) across fused samples to deliver a constant sample yield to the mass spectrometer without inter-element fractionation effects during each analysis. Capabilities of the method are demonstrated by determination of twenty five trace elements (Sc, Ti, V, Ga, Rb, Sr, Y, Zr, Nb, Cs, Ba, REE, Hf, Ta, Pb, Th and U) in a diverse range of geological reference materials that includes peridotites, basalts, granites, metamorphic rocks and sediments. More than 90% of determinations are indistinguishable from published reference values at the 95% confidence level. Systematic bias greater than 5% is observed for only a handful of elements (Zr, Nb and U) and may be attributed in part to inaccurate calibration values used for the NIST SRM 612 glass in the case of Zr and Nb. Detection limits for several elements, most notably La, are compromised at ultra-trace levels by impurities in the lithium borate flux but can be corrected for by subtracting appropriate procedural blanks. Reliable Pb analysis has proved problematic due to variable degrees of contamination introduced during sample polishing prior to analysis and from Pt-crucibles previously used to fuse Pb-rich samples. Scope exists for extending the method to include internal standard element/isotope spiking, particularly where integrated XRF analysis is not available to characterise major and trace elements in the fused lithium borate glasses prior to LA-ICP-MS analysis.  相似文献   

18.
本实验采用湿法消解碳酸盐岩矿石样品,利用电感耦合等离子体发射光谱仪(ICP-AES),采用内标法和基体匹配法相结合测定了碳酸盐岩标准物质(GBW10035a)中高达54%的氧化钙主量元素含量及其它常微量元素的含量;对实际样品中微量元素进行样品加标回收率实验,对主量和常量元素采用稀释法验证。实验结果表明,样品加标回收率在94%~108%之间,稀释比率在99.4%~100.2%,标准物质测定值与标准值吻合,6次平行样测定的稳定性4%;该方法一次溶样,径向测定主量和常量元素,轴向测定微量元素含量,操作简单,快速,该方法适用于盐湖碳酸盐样品,以及其他含有碳酸盐的各类样品的分析测试。  相似文献   

19.
标准物质参考值的准确性在测试仪器校准、分析数据质量监控以及方法评价等方面具有非常重要的作用.为了检验国家地质标准物质参考值的准确性,本文应用高温高压密闭溶样-电感耦合等离子体质谱法分析了国家地质标准物质的18种岩石(GBW 07103 ~ GBW 07125)、19种沉积物(GBW 07301 ~ GBW 07318)和19种土壤(GBW 07401 ~ GBW 07430)中36种痕量与稀土元素.结果表明,除个别标准样品中的几个元素(Ni、Cr、Pb、Co、Cu、Sc、Yb、Lu)外,其余国家标准物质中36种元素测定结果的相对标准偏差均小于10%;绝大部分元素测定值的相对误差小于10%,测定值与参考值能较好地吻合.将误差较大元素的测定值与其他实验室的测定值以及文献报道值进行了比较,指出已有的参考值需要修正;针对部分沉积物和土壤中的元素未提供参考值,如GBW 07306的Ni、GBW 07313的Be、Hf、Ta,GBW 07314的Li、Be,GBW 07409、GBW 07410和GBW0741 1的Hf、Ta,GBW 07426的Gd、Ta,本文给出了相应的参考值.  相似文献   

20.
The concentrations of Ti, Zr and Hf have been determined, by a stable isotope dilution method, in 27 chondrites, seven achondrites and standard rock samples BCR-1 and W-1.Among all chondrites investigated, enstatite chondrite Abee is lowest in Ti atomic ratio compared with Si while all carbonaceous chondrites show higher values. The Zr contents are higher in CII and CIII chondrites, relative to the other groups of chondrites. There is a clustering of Ti and Zr within each group. The ZrHf ratios in CII, CIII. E and H chondrites are essentially the same, while that in the CI chondrite is lower and in L, LL and unequilibrated chondrites are higher.The concentrations of Ti, Zr, Hf and TiZr, ZrHf ratios in achondrites are variable, even among members of the same group.Based on these results, condensation models for these elements are discussed. The variable results for Ti, Zr and Hf in achondrites may be due to the reheating recrystallization and metamorphic processes.‘Cosmic atomic abundances’ of Ti, Zr and Hf are calculated as 2470, 11.2 and 0.185. respectively for Si = 106 atoms.  相似文献   

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