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1.
电感耦合等离子体质谱法测定高锡地质样品中的痕量镉 总被引：1，自引：1，他引：0
应用电感耦合等离子体质谱法(ICP-MS)测定地质样品中的痕量镉,存在多种质谱干扰,通常采用在线或离线方程进行校正,当样品中含锡较高时,采用传统固定系数校正方程,易导致测定结果有明显偏离,甚至结果出现负数。本文针对含高锡的地质样品,应用ICP-MS测定其中的镉,采用氢氟酸-高氯酸-硝酸敞开酸溶消解、硝酸浸提体系处理样品,通过测定~(111)Cd、~(113)Cd、~(114)Cd同位素,研究了干扰元素Sn、In、Zr、Mo对镉测定的影响。结果表明镉与干扰源浓度变化呈非简单的正相关性。①同质异位素Sn或In产生的干扰增值Δ(~(114)Cd/~(114)Sn或~(113)Cd/~(113)In)随干扰源浓度增大逐渐变大,~(114)Sn对~(114)Cd的干扰系数在0.0272～0.0222,~(113)In对~(113)Cd的干扰系数在0.0670～0.0412;②Zr和Mo在测定条件下形成氧化物和多原子复合离子物质对Cd均产生不同程度的质谱干扰。通过测定与样品中干扰源浓度相近的单一标准溶液产生的Cd干扰值,经在线修正干扰系数(γ),建立了精确的校正方程。该方法经标准物质验证,准确度高,相对标准偏差在6.57%～9.94%(n=7),方法检出限为0.03mg/kg,达到了地质分析检测要求,为高锡地质样品中的痕量镉分析提供了依据。 相似文献
2.
保证Cd的高回收率以及彻底的Sn干扰去除是获得精确镉同位素组成的前提,目前报道的多种Cd分离与纯化方法获得的Cd回收率有较大差异(42.6%~99.8%),且去除Sn干扰的效果也不同(去除率在87.8%~97.4%之间),Cd回收率和Sn去除率均不理想。本文对前人报道的分离方法进行对比实验,发现0.1 mol/L氢溴酸-0.5 mol/L硝酸是分离Cd和Sn的有效试剂,增加该组混合酸的用量可淋洗出样品中更多的Sn且不会损失Cd,当混合酸的淋洗用量增加至30 mL时,Sn的淋洗率达到99.8%以上,Cd的回收率亦达到99.0%±0.5%,可满足土壤样品镉同位素的测定要求。本工作为获得高精度的镉同位素组成奠定了基础,为研究土壤环境中镉的污染来源提供了技术手段。 相似文献
3.
用D201阴离子交换树脂富集样品中的痕量Cd，使Cd与共存干扰元素Cu、Ni、Pb、Zn有效分离，消除了这些元素对镉蒸气发生的干扰，从而建立了断续流动在线分离富集-蒸气发生原子荧光光谱法测定复杂环境样品中痕量Cd的分析方法。方法的检出限为3ng／L（3σ）；测定精密度（RSD）为1．9％（对1μg/L Cd，n=11）。用该方法对国家一级标准物质（土壤、水系沉积物和岩石）中的痕量镉进行了测定，结果与标准值相符。 相似文献
4.
147Sm-143Nd放射性同位素体系在地球科学研究中得到了广泛的应用,经典的同位素稀释-热表面电离质谱法(ID-TIMS)一直是Sm-Nd同位素高精度测定的基准技术,但具有耗时长、成本高、样品需求量大等缺点,并且难以揭示微观尺度单矿物所蕴含的地球化学信息。近年来兴起的微区原位分析,具有简单、快速、高空间分辨率的特点,可以从微米尺度示踪岩浆和热液的起源及演化过程。本文通过同时测定Sm和Nd同位素质量分馏系数,实现144Sm对144Nd干扰的准确校正,获得了人造玻璃、磷灰石、榍石、独居石等几种不同基体标准样品(NIST610、Durango、MAD-2、BLR-1、117531)精确的143Nd/144Nd比值,与推荐值在误差范围内一致。然而,由于Sm和Nd元素性质的差异,在激光剥蚀和质谱电离过程中会产生明显的元素分馏,导致147Sm/144Nd很难进行精确校正,本文通过在进样系统中引入液态气溶胶,有效克服了基体效... 相似文献
5.
利用MC-ICPMS精确测定143Nd/144Nd和Sm/Nd比值 总被引：43，自引：14，他引：43
多收集器等离子体质谱(MCICPMS)用于分析SmNd同位素时,质量分馏系数(β)与同位素的质量数呈线性关系.可以采用两种方法进行质量分馏校正:双分馏系数内部校正法(DFIC)和单分馏系数外部校正法(SFEC).采用DFIC法,对国际标样ShinEtsuJNdi1和实验室标样NdGIG进行了为期五个月的143Nd/144Nd比值测量统计,结果分别为0.512120±0.000012(2σSD)、0.511532±0.000013(2σSD).采用SFEC法,对NdGIG标样的测量统计结果为0.511525±0.000015(2σSD).两种方法的测量结果在分析误差范围内与其推荐值或TIMS测量值完全一致.对加Ce和Sm的NdGIG混合溶液分别进行了Ce和Sm对143Nd/144Nd比值分析的干扰校正研究和Sm/Nd比值测量,结果显示,143Nd/144Nd比值分别与Ce/Nd、Sm/Nd测量值呈线性关系,Sm/Nd测量值与其质量比值亦呈很好的线性关系.这表明利用MCICPMS可以快速精确地测定存在Ce、Sm干扰的样品的143Nd/144Nd比值,同时可获得精确的Sm/Nd比值,而无需加入稀释剂.这就使直接测定地质样品的SmNd等时线年龄成为可能. 相似文献
6.
《矿物岩石地球化学通报》2016,(3)
本文综述了近10年来激光原位LA-MC-ICP-MS测定地质样品Sm-Nd同位素测试技术的最新进展,着重介绍了同质异位素干扰校正的关键技术难点及校正方案。LA-MC-ICP-MS技术对轻稀土富集矿物可以获得可靠的~(147)Sm /~(144)Nd and~(143)Nd /~(144)Nd值,是当前进行地质样品激光原位Sm-Nd同位素测定的主要技术,配合矿物微区U-Th-Pb年龄测定和微量元素分析,可以对矿物的成因演化提供重要的制约参数。多元同位素体系(Sr-Nd-Hf同位素、U-Th-Pb年龄和微量元素)的原位微区联合测定,低含量地质样品(小于500μg/g)和高Sm/Nd值矿物(如磷钇矿Sm/Nd远远大于1,有时甚至达到10)的Sm-Nd同位素组成的准确测定是未来LA-MC-ICP-MS激光原位Sm-Nd同位素测定的主要发展方向之一,具有广阔的应用前景。 相似文献
7.
《矿物学报》2013,(4)
锗物料的选冶是高纯锗提纯前必经的重要阶段,详细分析锗物料的主要成分可以对锗物料的进一步选冶提纯起到事半功倍的作用。试验采用ICP-OES法对锗物料中Ge等主要元素进行测定,研究了锗物料试样制备和分解方法的选择和优化,讨论了溶液中硫酸酸度对被测元素谱线强度的影响。方法的检出限为0.00140.0407μg/mL,相对标准偏差小于3%,回收率介于95.22%0.0407μg/mL,相对标准偏差小于3%,回收率介于95.22%102.4%。方法得到的Ge结果和现行国家标准方法得到的结果相吻合。结果表明,该方法快速准确、回收率高,是目前较理想的锗物料中Ge-As-Cu-Pb-Sb-Sn-Zn等多元素准确测定方法。 相似文献
8.
电感耦合等离子体质谱法测定铅合金中的微量杂质元素镉和锡 总被引：1，自引：1，他引：0
铅合金中的镉和锡由于含量较低,国家标准方法均为单一元素分析,步骤繁琐,检出限高,难以达到理想的检出要求。本文建立了应用电感耦合等离子体质谱法(ICP-MS)测定铅合金中微量级(μg/g级)杂质元素镉和锡的分析方法。采用单一的低浓度硝酸溶解铅合金,用低温慢溶的方式使样品溶解更加完全,减少了多离子对仪器的干扰;通过铅基体匹配和加入酒石酸保证了标准与样品介质的一致性,同时避免了锡的水解;以~(103)Rh作为内标元素,~(111)Cd和~(118)Sn作为测量同位素克服了质谱干扰。方法检出限为镉0.05 ng/g、锡0.04 ng/g,比国家标准方法的检出限(1~6μg/g)低,精密度小于4%。该方法试剂用量少,减少了处理样品的复杂性,实现了合金中微量级元素的准确测定。 相似文献
9.
膜去溶-电感耦合等离子体质谱法测定环境地质样品中的镉 总被引：3，自引：3，他引：0
应用电感耦合等离子体质谱法(ICP-MS)分析环境地质样品中的Cd时,Zr、Mo元素的氧化物和氢氧化物会对Cd造成严重干扰,导致结果有明显的偏差。针对此问题,本文建立了膜去溶-ICP-MS直接测定环境地质样品中微量Cd的分析方法,该方法可有效地消除Zr、Mo氧化物和氢氧化物对Cd的干扰,保证结果准确、可靠。膜去溶-ICP-MS相比于常规ICP-MS测定Cd的方法,可将Zr、Mo氧化物和氢氧化物对Cd的干扰降低到0.001%,检测灵敏度提高3.5倍左右。在给定条件下,Cd的检出限为0.28 ng/L,测定下限为2.2 ng/L,精密度(RSD,n=12)为2.2%。利用该方法分析20种岩石、土壤和沉积物国家标准物质的测定值与标准值相符,表明膜去溶-ICP-MS法直接测定环境地质样品中痕量或超痕量Cd时具有一定的应用潜力。同时,用该方法对2016年中核集团组织的实验室间两个比对样品中的Cd进行测定,稳健Z比分数分别为0.500和-0.964,Z的绝对值都小于2。 相似文献
10.
纳雍枝铅锌矿床是贵州省内发现的第一个大型铅锌矿床,前人对该矿床进行过大量地质和地球化学研究,对该矿床成因有了一定认识,但其成矿金属来源,特别是其中稀散金属(如Cd)的来源却少有涉及。本文分析了该矿床硫化物和精矿样品的微量元素及镉同位素组成,结合该区域不同地质端元的地球化学数据,来探讨以Cd为代表的稀散金属来源。结果表明,样品的Zn/Cd值变化较大(377～953),均高于川滇黔地区沉积岩的Zn/Cd比值(13～367),而更接近火成岩的Zn/Cd值(515～1319)。精矿和闪锌矿样品的镉同位素组成(δ114/110Cd NIST-3108)变化范围极小(-0.09‰～-0.05‰),与已获得的岩浆岩数据一致(-0.22‰～0.15‰),但明显区别于该地区的碳酸盐岩地层(-0.25‰～0.82‰)。结合精矿的Zn/Cd-δ114/110Cd NIST-3108关系图解和前人研究成果,本文认为该矿床金属成矿物质(如镉、铅等)主要来自基底。 相似文献
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12.
位于江南造山带中段的湘东北地区是我国华南重要的金铅锌铜钴多金属矿产地之一,栗山铅锌铜多金属矿床是该区近年来找矿勘查新发现的一大型矿床。该矿床位于晚侏罗世—早白垩世幕阜山岩体南缘,矿体主要赋存于岩体及其与地层接触带的构造破碎带内,空间上与岩体关系密切,然而目前关于该矿床的研究十分薄弱。本文采用电子探针和激光剥蚀电感耦合等离子质谱仪开展了闪锌矿的原位微区微量元素分析。微量元素组成分析结果表明,闪锌矿以富集Co、Ga而贫Fe、Cd、Ge为特征,其中Fe、Mn、Cd、Co、Ga等元素以类质同象形式产出,而Cu、Pb、Ag和Sn等元素则还以包裹体形式赋存于闪锌矿中。根据不同微量元素间的相关关系,认为闪锌矿中可能存在Zn2+↔Fe2+、4 Zn2+↔2 Fe2++Ge4++□(其中□表示空位)、3 Zn2+↔2 Cu++Ge4+、2 Zn2+↔Ag++Sb3+等简单和复杂替代关系。闪锌矿的Zn/Fe、Ga/Ge、Ge/In、Ga/In比值和Fe温度计等指示闪锌矿形成于中低温(240~250 ℃)、低硫逸度(lgf(S2)=-13.3~-9.6)环境。栗山矿区闪锌矿的微量元素组成特征有别于金顶砂岩型、SEDEX型、VMS型、MVT型和夕卡岩型铅锌矿,结合低的Cd/Fe(0.03~0.14,平均0.06)、Cd/Mn(1.54~6.30,平均2.91)比值和Ge含量,暗示该矿床成矿作用与岩浆活动有关。综合矿区地质特征和区域构造-岩浆演化,认为该矿床是在太平洋板块俯冲后撤引起的伸展构造背景下形成的与燕山期幕阜山岩体有关的中低温岩浆热液充填交代型矿床。该类型矿床闪锌矿具有鲜明的微量元素组成特征,可为判别具相似地质特征的矿床成因提供借鉴。 相似文献
13.
Precise Determination of Cadmium, Indium and Tellurium Using Multiple Collector ICP-MS 总被引：1，自引：1，他引：0
Wen Yi Alex N. Halliday Der-Chuen Lee Mark Rehkämper 《Geostandards and Geoanalytical Research》1998,22(2):173-179
New sample preparation and ion-exchange separation methods as well as instrumental measurement protocols were established for the determination of trace-level Cd, In, and Te concentrations in geological materials by isotope-dilution mass spectrometry. High precision isotope ratio measurements were performed with a multiple collector inductively coupled plasma-mass spectrometer (MC-ICP-MS). The mass biases incurred for In and Te were corrected by adding and monitoring Pd and Sb standard solutions, respectively. Mass fractionation of Cd was corrected by using the mass fractionation factor calculated from the measurement of a standard solution. The measurement precision was better than 1 % for Cd, In and Te. Detection limits were < 1 ng g-1 for Cd, < 0.02 ng g-1 for In and Te. Using these new analytical techniques, the concentrations of Cd, In and Te were determined in six international geological reference materials. Concentrations could be reproduced within 3% for Cd, 4% for In and 10% for Te. Sample heterogeneity and volatility problems might have been the reason for the relatively large differences between Te replicates. Our results displayed excellent reproducibility compared with those of other techniques and agree well with data from previously published recommended values. 相似文献
14.
Christophe Cloquet Olivier Rouxel Jean Carignan Guy Libourel 《Geostandards and Geoanalytical Research》2005,29(1):95-106
In this study, the Cd isotopic composition of various geological reference materials and anthropogenic samples was investigated. The measurements were made by multicollector ICP-MS and instrumental mass fractionation was controlled using a "sample-standard bracketing" technique. Cadmium isotopic data are reported relative to an internal Cd solution (Cd Spex) and expressed as the 114 Cd/110 Cd delta value. Two other Cd solutions (Prolabo and JMC) were analysed and yielded the same 0% delta value. A fractionated Cd metal sample (Münster Cd) was used as a secondary reference material for Cd isotopic measurements and we obtained a 114 Cd/110 Cd delta value of 4.48% relative to Cd Spex solution. As opposed to multi-stage Cd purification previously published in the literature, a new one step anionic exchange purification using dilute HCl for the analysis of Cd isotopes in geological samples was developed. This method enabled a high recovery (> 95%) and effective separation of the sample matrix to be achieved. The long-term external reproducibility was evaluated at 0.12% (2 standard deviations) for the 114 Cd/110 Cd ratio, based on reference solutions and replicated measurements of samples over one year. The variation of Cd isotopic composition of natural terrestrial samples is restricted to a small range of 0.4%, which is similar to previously reported results. In contrast, large variations of Cd isotopic composition were found for anthropogenic samples with values as low as −0.64% for a dust sample issued from a lead smelter and values as high as +0.50% for NIST SRM 2711 (metal-rich soil). These variations are 10 times larger than the reproducibility and suggest that Cd isotopes can be useful as tracers of anthropogenic sources of Cd in the environment. 相似文献
15.
测算全新世之前地质事件过程时间(需要精度万年级),没有现行可以采用的定年方法(误差精度百万年级),因此有必要探索构造地质自组织的时限定年方法(万年级)。本文以滨西太平洋构造系郯庐断裂带为实例,通过石英位错密度法测得差异应力σ分别为:糜棱岩化岩石为141.17MPa,糜棱岩为191.88MPa,超糜棱岩为223.31MPa;相应的应变速率分别为3.760×10-13s-1、7.705×10-13s-1和1.087×10-12s-1;体积因子fv相应依次为0.7923、0.6340和0.5886;所得构造形成时限t依次为2.08×104a、1.83×104a和1.44×104a。为检查精度,对同一剪切带不同应变强度样品进行系统内的比较分析,剪切带边缘样品的t值明显大于剪切带中心部位,在目前尚无地球化学方法可供借用检验的条件下,本文首次提出的自检验方法是一种提高精度的有效尝试。文中有关时限定年的系统讨论,是对以往时限定年的校正和总结,这有助于构造地质学定量化的发展,也是对构造年代学的一项补充。 相似文献
16.
Allison Forrest Richard Kingsley Jean-Guy Schilling 《Geostandards and Geoanalytical Research》2009,33(2):261-269
Promising methods have been developed recently for the determination of selenium (Se) and tellurium (Te) in geological materials at ng g−1 and lower levels, using hydride generation-inductively coupled plasma-mass spectrometry. Here we report on a new isotope dilution-hydride generation-inductively coupled plasma-mass spectrometry (ID-HG-ICP-MS) method for the simultaneous determination of Se and Te, which is applied to basalts, and modified compared to previous work. The basalts were attacked and dissolved with hydrofluoric and nitric acid, spiked with enriched isotopes, and passed through a cation exchange column (AG 50-X8 100–200 mesh) to separate the major cations that interfere with Se and Te detection (e.g., Fe). The detection limits of this method were 0.010 ng g−1 for Se and 0.0030 ng g−1 for Te, well below the concentrations of Se and Te expected in basalts. The precision of the method for Se was 12.2 to 15.1% and for Te was 4.6 to 7.2% RSD from replicate analyses of basalt reference samples. The accuracy for Se determinations was 61 to 94% and for Te 28 to 100% of values previously reported in the literature for selected USGS reference materials. 相似文献
17.
Li Bing Ma Xinrong Han Lirong Yang Hongxia 《Geostandards and Geoanalytical Research》2004,28(2):317-323
A simple sample treatment method for the accurate and precise determination of iodine in soil, sediment and biological samples by inductively coupled plasma-mass spectrometry (ICP-MS) is described. Iodine in samples was extracted in screw top PTFE-lined stainless steel bombs using a 10% v/v ammonia solution at 185 C for 18 hours (overnight), after which the extract was introduced into the ICP-MS for direct measurement. 126 Te was employed as the internal standard to compensate for matrix effects and instrument drift. The limit of detection (LOD, three times the standard deviation of the procedural blank solution, expressed as the concentration in the sample solution) was 0.003 ng ml--1 . The limit of quantitation (LOQ, ten times the standard deviation of the procedural blank solution, expressed as the concentration in the solid samples, dilution factor DF = 100) was 0.01 μg g--1 (dry mass). The accuracy and precision of the method were demonstrated by analysing different Chinese geological certified reference materials (soils, stream sediments and a hair sample). The measured concentrations were in a good agreement with the certified values indicating that bias in the method was not significant. The precision (n = 10) for different concentrations ranged from 1.82% to 4.32% RSD. Comparison of the ammonia extraction procedure with a "sintering" method indicated that there was no significant difference in results obtained with the two methods for geological soil and stream sediment samples. However, for biological samples, such as hair, kelp, tea etc., the results obtained by the sintering method were far below those of the ammonia extraction method. The ammonia extraction has advantages, as it is simpler than the "sintering" method, and has a lower procedural blank, better detection limits and reproducibility. Due to the simplicity of the method, a high rate of sample throughput is possible. 相似文献
18.
A new method has been developed for the determination of platinum and palladium based on separation and preconcentration with a microcolumn packed with nanometric TiO2 immobilised on silica gel (immobilised nanometric TiO2 ) prior to their determination by inductively coupled plasma-atomic emission spectrometry. The optimum experimental parameters for the preconcentration of Pt and Pd, such as the pH of the sample solution, its flow rate and volume, the type and concentration of eluent and interfering ions, have been investigated. Platinum and Pd could be quantitatively retained by immobilised nanometric TiO2 in the pH range 6–8, then eluted completely with 2.0 ml of 3% m/v thiourea in 1.0 mol l−1 HNO3 . The detection limits of this method for Pt and Pd were 12 and 7. 6 ng l−1 with an enrichment factor of 100, and the relative standard deviations were 4.7% and 3.3% at the 10 ng ml−1 level. The method has been applied for the determination of Pt and Pd in geological samples with satisfactory results. 相似文献
19.
A method for the determination of Ge, As, Se and Te in silicate samples using isotope dilution-internal standardisation (ID-IS) octopole reaction cell (ORC) ICP-QMS by normal sample nebulisation was developed. The method does not involve either hydride generation or ion exchange. Germanium, Se and Te were determined by isotope dilution (ID), and As was determined by ID-IS. A silicate sample with an added Ge-Se-Te spike was digested with an HF-HNO3 -HBr mixture, dried, re-dissolved with HF and the supernatant liquid was directly aspirated into an ORC-ICP-QMS instrument with He or H2 gas. No matrix effects were observed down to a dilution factor (DF) of ∼ 70 for Ge, Se and Te and DF of ∼ 1000 for As, which resulted in 3s detection limits in silicates of 2, 1, 0.1 and 4 ng g−1 , respectively. Advantages of the method are the simple sample introduction as well as a capability of determining S, Ti, Zr, Nb, Mo, Sn, Sb, Hf and Ta by ID-IS-ICP-QMS/SFMS from the same solution. Furthermore, the total sample solution consumption was only 0.253 ml with DF = 2000. Therefore, only a 0.13 mg test portion was required. To demonstrate the applicability of this technique, Ge, As, Se and Te in eight silicate reference materials were determined, as well as S, Ti, Zr, Nb, Mo, Sn, Sb, Hf and Ta in four carbonaceous chondrites. 相似文献