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ICP—MS法直接测定冰芯样品中的超痕量镉 总被引:2,自引:0,他引:2
采用ICP-MS法对冰芯样品中超痕量Cd的直接测定进行了研究。确定了直接测定浓度为pg/mL级的Cd的最佳参数、载气流速、进样速度等与灵敏度之间的关系以及浓度和扫描参数对分析精度的影响。本方法对浓度5-200pg/mL Cd的分析,RSD<10%,回收率在88%-105%之间,检测限为0.15pg/mL。 相似文献
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建立了ICP-MS测定分析果蔬类、大米等农产品样品中痕量元素的方法。样品通过HNO3-H2O2混酸体系微波消解,以Rh作为内标溶液消除基体干扰,在仪器最佳条件下测定植物样中镉、铅、铬、铜、镍、锌六种痕量元素。结果表明:检出限为0.002~0.5ug/g ;相对标准偏差(RSD)为0.84% ~7.35% 。利用所建立的方法测定了大米(GBW10010)、小麦(GBW10011)、芹菜(GBW10048)、大葱(GBW10049)4种标准物质,分析结果均在参考值范围内。方法简单、快速、准确,适用于批量样品中多元素的同时测定。 相似文献
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探讨了聚氨酯泡沫塑料的预处理,样品浓度,水洗条件,基体元素对金吸附率的影响。结果表明,用泡沫塑料吸附含金量为5ng-500μg的溶液,吸附率均在90%以上。影响聚氨酯泡沫塑料吸附率的重要条件是振荡前要用水充分浸透,水洗基体元素,矿渣宜在酸性环境下进行。铁、钛等离子可以提高吸附率,钠,钙,锌,矿渣等影响不显著,铝离子有微弱的拟制作用。ICP-MS的灵敏度与介质的雾化率有一定的相关性,应当使用硫脲介质的工作溶液作为工作曲线,内标元素可用103Rh或185Re,但是对于高W样品,只能使用103Rh。用金矿石国家标准物质做精密度与准确度验证,测定值与标准值无显著差异,标准偏差(RSD)均小于10%,精密度能满足地球化学样品中的痕量金的分析要求。 相似文献
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运用三重串联电感耦合等离子质谱(ICP-MS/MS)仪直接测定高纯Eu_2O_3中超痕量的Tm,As和Si。采用H_2的原位质量法和O_2质量转移法,有效克服了基体对待测元素的干扰。通过优化仪器参数得到Tm,As和Si的背景等效浓度分别为0.0005763,0.08435,8.268μg·L~(-1)。在选定条件下,样品加标回收率为95.74%~103.82%,相对标准偏差(RSD)为0.22%~4.38%。本方法简单实用,能够满足纯度99.999%以上的高纯Eu_2O_3中杂质元素的快速测定。 相似文献
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地球化学样品中痕量镉(0.0Xppm)不经分离富集直接用无火焰原子吸收法测定是困难的。现有文献多采用分离富集后才能测定,或加入基体改进剂,我们曾在此基础上进行试验与探讨,但基体干扰仍未能消除。我们发现,用硫脲-EDTA盐-磷酸二氢铵作为基体改进剂,能消除基体干扰且提高了镉的原子化效率,无需分离富集可直接测定地球化探样品中痕量镉。用拟定的方法测定地球化学标准样中镉的结果与可用值相符,本法灵敏,快速、能满 相似文献
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流动注射离子交换预浓集火焰原子吸收光谱法直接测定人尿中痕量镉 总被引:2,自引:0,他引:2
应用高效的流动注射在线离子交换预浓集火焰原子吸收光谱测定系统直接测定了人尿中痕量镉。选择200μL锥形离子交换柱,内装多孔玻璃固定化的8-羟基喹啉离子交换剂,在pH9条件下样品流速为3.5mL/min,40s装样,用2mol/LHCl洗脱,在分析速度为60样/h,获得30倍的富集倍率。检出限为0.3μg/L。镉含量水平为40μg/L的尿样,连续测定11次的相对标准偏差为1.5%。尿标准参考物...? 相似文献
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建立了微波辅助HNO3消解样品,ICP-MS快速测定生物样品中Ti、Cr、Mn、Fe、Co、Ni、Cu、Zn、Ge、As、Se、Sr、Mo、Ag、Cd、I、Ba、Hg、Tl、Pb、Bi共21种微量及痕量元素。通过在线加入内标来校正基体效应和信号漂移对测量所造成的影响。各元素线性相关系数在0.9990以上,RSD小于6.0%。用本方法对国家标准样品GBW07601a(头发),GBW10010(大米),GBW10016(茶叶),GBW10023(紫菜)进行分析,结果满意。方法能满足生物样品痕量分析的要求。 相似文献
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王水提取-电感耦合等离子体质谱法同时测定地质样品中微量银、镉、铋 总被引:21,自引:0,他引:21
样品用水浴加热、王水提取预处理,采用电感耦合等离子体质谱法同时测定了土壤、水系沉积物及岩石等地质样品中的痕量Ag、Cd和Bi。在样品预处理阶段,主要干扰元素Zr和Nb只有少量被溶出,而分析元素Ag、Cd和Bi的溶出趋于完全,这样在样品预处理阶段就完成了分析元素与干扰元素的有效分离,减小了多原子离子93Nb16O ,92Zr16OH ,92Mo16OH 对109Ag的干扰和95Mo16O ,94Zr16OH ,94Mo16OH 对111Cd的干扰。方法对实际样品的检出限(10σ,DF=300)Ag,Cd和Bi的质量分数分别为5.1,4.3和10.5ng/g。对不同含量样品7次测定的RSD为8.7%~1.8%。用该方法对土壤、水系沉积物及岩石等国家一级标准物质进行分析,分析数据均在标准推荐值的允许误差范围内。 相似文献
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ICP-MS法测定金属镝中的非稀土杂质 总被引:1,自引:0,他引:1
用ICP-MS法对高纯金属镝中10种非稀土杂质Al、Fe、Ni、Ti、Co、Cd、Mn、Pb、Cu、Ba、Mg的测定进行了研究。估算了元素的测定下限;研究了酸度影响;并进行了不同方法的结果对照实验;采用In作内标,方法的加标回收率在80.5%-110.2%之间,相对标准偏差低于12%。 相似文献
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A method has been described for the determination of iron from fish otoliths containing high levels of calcium by collision cell technology (CCT) ICP-MS. Iron (Fe) in otolith solutions was quantitatively coprecipitated with small amounts of calcium hydroxide by adding 1.0 M sodium hydroxide solution. The performance of CCT-ICP-MS pressurized with He/H(2) cell gas was investigated on the elimination of Ca-based spectral interferences at m/z 54, 56 and 57. Molecular ion interferences at m/z 54 and 56 were reduced by 2 orders of magnitude. However, the interferences at m/z 57 increased by the same amount in the presence of Ca in solutions owing to the formation of (40)Ca(16) OH(+) through reactions with H(2) in collision cell, indicating that (57)Fe was not suitable for the determination of Fe from otoliths. Results for (56)Fe suffered significantly from interferences of Ca-based molecular ions when the Ca concentration in solution exceeded 100 microg ml(-1), for which matrix-matched calibration was required for accurate determination. CCT with the aid of He/H(2) cell gas proved to be very effective in eliminating the interferences ((40)Ar(14)N(+) and (40)Ca(14)N(+)) at m/z 54. Presence of Ca up to 300 microg ml(-1) had virtually no effect on the ion signals of (54)Fe, which with low background signals, afforded accurate determination of Fe from otoliths by using aqueous external standards. 相似文献
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稀土化合物中Cl-的ICP-MS测定 总被引:4,自引:0,他引:4
研究了用ICP-MS法测定稀土化合物中Cl^-1。对分析线,内标元素和基体浓度进行了合理选择。方法的加标回收率在80%-125%。相对标准偏差在6.24%-14.70%,测定下限为0.005%。 相似文献
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Cloud point extraction for ultra-trace Cd determination in microwave-digested biological samples by ETAAS 总被引:1,自引:0,他引:1
Pedro R. Aranda 《Talanta》2008,77(2):663-666
Cloud point extraction (CPE) has been used for the preconcentration of cadmium, after the formation of a complex with 2-(5-bromo-2-pyridylazo)-5-(diethylamino)-phenol (5-Br-PADAP), and further determination by graphite furnace atomic absorption spectrometry (ETAAS) using polyethyleneglicolmono-p-nonyphenylether (PONPE 7.5) as surfactant. The chemical variables that affect the cloud point extraction were optimized. The separation of the two phases was easily accomplished by cooling the mixture in order to make more viscous the surfactant-rich phase. In order to establish the optimum conditions for the determination of Cd by ETAAS, Pd + Mg, Pt, Ir, Rh and Ru were studied as chemical modifiers. The best thermal stabilization was obtained with Pd + Mg, with a maximum pyrolysis temperature of 1100 °C. Under the optimum conditions i.e., pH 9.0, [5-Br-PADAP] = 2.0 × 10−5 mol L−1, [PONPE 7.5] = 0.02% (w/v), an enhancement factor of 22-fold was reached. The lower limit of detection (LOD) obtained under the optimal conditions was 0.008 μg L−1. The precision for 10 replicate determinations at 0.2 μg L−1 Cd was 3.5% relative standard deviation (R.S.D.). The calibration graph using the preconcentration method was linear with a correlation coefficient of 0.9984 at levels close to the detection limit up to at least 1.0 μg L−1. The method was successfully applied to the determination of cadmium in urine samples and in a water standard reference material. 相似文献
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Direct determination of total carbonate salts in soil samples by continuous-flow piezoelectric detection 总被引:1,自引:0,他引:1
Two new methods for the determination of total carbonate salts, as CaCO3, in soil by continuous-flow piezoelectric (PZ) detection are proposed. Both use a piezoelectric flow cell and a manifold including a dynamic gas extraction device to purge gaseous CO2 released by the sample solution upon acidification. One of the methods involves monitoring the pressure generated by the CO2 produced upon addition of hydrochloric acid; in the other, the CO2 is quantified by using a quartz crystal coated with tetramethylammonium fluoride tetrahydrate (TMAF). The precision of both methods is compared with that of the officially endorsed method. The proposed methods allow calcium carbonate amounts over the ranges 10-100 mg and 2-15 mg, respectively, to be determined. Both were applied to the determination of CaCO3 in soil samples. The standard deviation and throughput achieved were 2.7% and 30 samples per hour, respectively, with the pressure-based method; and 6.0% and six samples per hour, respectively, with the mass-based method. 相似文献