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采用氢化物发生-原子荧光光谱法测定低合金钢中砷的含量。样品经盐酸-硝酸混合酸消解,以盐酸(5+95)溶液为反应介质,15g·L~(-1)硼氢化钾-2g·L~(-1)氢氧化钾的混合溶液为还原剂,采用柠檬酸作为掩蔽剂。砷的质量浓度在60.0μg·L~(-1)以内与荧光强度呈线性关系,方法的检出限(3s/k)为0.023μg·L~(-1)。应用此法对标准钢样进行了分析,测定结果与认定值相符合,可满足钢铁中微量砷(质量分数0.001%~0.04%)的测定要求。 相似文献
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采用氢化物发生-原子荧光光谱法测定大蒜中砷和硒。样品经硝酸和高氯酸消解,在盐酸(5+95)溶液中,加入溶于50g·L~(-1)氢氧化钠溶液的20g·L~(-1)硼氢化钾溶液,使其与溶液中砷及硒离子反应生成氢化物。分析中采用载气流量依次为800mL·min~(-1),600mL·min~(-1),屏蔽气的流量均为1000mL·min~(-1)。试样溶液中加入硫脲-抗坏血酸混合溶液作为还原剂。于仪器中引入试样溶液0.5mL,按选定的工作条件操作。砷及硒的质量浓度分别在0.04~0.40,1.00~10.0μg·L~(-1)范围内与其荧光强度呈线性关系,方法的检出限(3s/k)砷为0.017μg·L~(-1),硒为0.314μg·L~(-1)。分别加入两元素的标准溶液作回收试验,测得砷和硒的回收率分别在95.3%~104.4%和94.7%~105.2%之间。 相似文献
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氢化物发生-原子荧光光谱法测定海产品中总砷 总被引:1,自引:0,他引:1
采用氢化物发生-原子荧光光谱法测定海产品中总砷的含量。样品经硝酸-高氯酸(4+1)混合酸消解,样品溶液中加入硫脲和抗坏血酸混合溶液作为预还原剂。于盐酸(5+95)溶液中加入10g.L-1硼氢化钾-5g.L-1氢氧化钾溶液使与溶液中砷离子反应生成氢化物。分析时采用载气流量为400mL.min-1,屏蔽气流量为800mL.min-1。砷的质量浓度在20μg.L-1以内与荧光强度呈线性关系,方法的检出限(3s/k)为0.015μg.L-1。应用此法对3种海产品进行分析,测定值的相对标准偏差(n=6)在3.4%~4.2%之间,回收率在98.5%~101.0%之间。 相似文献
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水系沉积物试样用盐酸-硝酸-水(3+1+4)混合溶液溶解,氢化物发生-原子荧光光谱法测定铋和汞的含量。对介质酸度、硼氢化钾浓度、负高压和灯电流等影响铋和汞测定因素进行了试验并予以优化。铋和汞的检出限(3S/N)分别为0.02,0.01μg.L-1,相对标准偏差(n=11)均小于0.5%。应用此法分析了水系沉积物标准样品,测定值与推荐值相符。 相似文献
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Development of a method for very low level selenium determination in water soluble protein and peptide fractions, obtained after various separation procedures, is presented. A hydride generation atomic fluorescence spectrometry (HG-AFS) detection system was optimised and the influence of Cu(II), Sb(V), As(III) and HNO3 interferences in the measurement of Se by HG-AFS was investigated. A destruction procedure using HNO3 and H2O2 was also optimised and the average recovery of the digestion of a solution of selenomethioneine was 92 ± 4% (n=14). Combination of this digestion with the detection system gave reliable results. Accuracy was tested by comparison with two independent methods. A very low detection limit (DL) of 0.2 ng/g of measuring solution was achieved. The whole procedure from weighing to measuring was performed in the same Teflon tube. The addition of HNO3 to the fractions before long term storage at -20°C was necessary to prevent adsorption on the test tubes.Selenium was measured in water soluble protein and peptide fractions obtained after extraction, and Sephadex G-75 chromatography performed on liver samples from: i) hens exposed to As2O3, ii) hens fed with a high fat feed and iii) the certified reference material dogfish liver (CRM DOLT-2). Because of the very low DL we were able to observe the Se distribution in chromatographic fractions of samples of organisms which were not exposed to excess amounts of Se. The presence of selenium associated with metallothioneins was observed. 相似文献
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An analytical result is not considered to be complete without a statement of the measurement uncertainty associated with
it. Evaluation of measurement uncertainty is therefore an essential part of every determination. In the present study the
measurement uncertainty of the result of determination of selenium in the reference material Seronorm Trace Elements Serum
was studied. The combination of a digestion procedure using sulfuric acid, V2O5 in H2SO4 and hydrogen peroxide and the continuous flow approach of hydride generation atomic fluorescence spectrometry (HG-AFS) detection
was used for selenium determination. The total uncertainty budget was calculated with the help of the GUM Workbench program,
in which computations follow the rules of the ’ISO guide to the expression of uncertainty in measurement’. The major sources
of uncertainty were found to be due to the recovery of the procedure, measurement of peak heights and the purity of Na2SeO3. A selenium mass fraction of 77.1±4.8 ng/g (with a coverage factor of 2.1, 95% probability) was determined, which is comparable
with the recommended value of 80 ng/g.
Received: 13 September 2002 Accepted: 23 December 2002
Acknowledgements We would like to thank Tinkara Buˇcar, B.Sc. for useful discussions and the IAEA Vienna, for financial support of the project
11553/RO.
Presented at CERMM-3, Central European Reference Materials and Measurements Conference: The function of reference materials
in the measurement process, May 30–June 1, 2002, Rogaška Slatina, Slovenia
Correspondence to V. Stibilj 相似文献
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