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单缝石英管原子捕集原子吸收光谱法测定了水中碲 总被引:6,自引:4,他引:2
研究了单缝石英管贫焰捕集-脉冲富焰释放原子捕集原子吸收光谱法测定碲的条件和线性范围;用X射线衍射分析得碲以Te4O11形式捕集,探讨了捕集、释放机理。测定质量浓度为20μg/L的碲(Ⅵ)时,捕集1min后测得特征质量浓度为1.76×10^-3mg/L,比常规FAAS法提高113倍,相对标准偏差为2.6%,已用于饮用水样中痕量碲的测定。 相似文献
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开缝石英管原子捕集原子吸收光谱法测定银 总被引:3,自引:0,他引:3
试验了空气和乙炔流量、缝管高度、捕集时间、溶液介质等对银灵敏度的影响。结果表明,分别用不同的乙炔流量进行原子捕集与释放可获得最高灵敏度。捕集1min,测得银的特征浓度为8.1×10~(-4)μg·ml~(-1),比常规火焰原子吸收法的灵敏度提高62倍,变异系数2.8%,本法测定了牡蛎中的银。 相似文献
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缝管原子捕集法中的原子化机理 总被引:12,自引:0,他引:12
本文用X射线衍射分析法研究了11个元素在开缝石英管中原子捕集与释放机理。Ag和Bi以金属形式被捕集,而Cd、Cu、In、Ni、Sb、Zn、Pb、Co、Ga则以氧化物或硅酸盐形式捕集。这些元素在放时直接从熔融物蒸发原子化。5%乙醇或丙酮能提高大多数元素的灵敏度。大多数元素在Al23涂层管上的灵敏度较高,在La2O3涂层管上的检出限较低,精密度较高。 相似文献
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开缝石英管原子化技术的改进 总被引:3,自引:0,他引:3
近年来,为提高火焰原子吸收光谱法的灵敏度,先后研究过水冷石英管和开缝石英管(简称缝管)原子化技术.前者使灵敏度提高1~2个数量级[1~3],后者只提高几倍[4~6].缝管技术比水冷石英管技术的装置简单,操作方便快速,但因其灵敏度不高,应用受到限制.本文以镉为例,探讨了提高缝管技术灵敏度的途径. 相似文献
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萃取—缝管原子捕集原子吸收法测定水中碲(Ⅳ)和磅(Ⅵ) 总被引:8,自引:0,他引:8
研究了碲(Ⅳ)和碲(Ⅵ)在DDTC-CCl4体系中的萃取和反萃取行为,并用缝管原子捕集技术结合火焰原子吸收法测定了水样中的碲(Ⅳ)和碲(Ⅵ),特征浓度为1.2g/L/1%吸收,检出限0.2μg/L,相对标准偏差1.7%,富集倍中达100%。 相似文献
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缝管原子捕集方法研究 总被引:1,自引:0,他引:1
试验了各种条件对Bi、Ga、Sb灵敏度影响。结果表明,分别用不同的火焰条件进行原子捕杀与放可获得最佳灵敏度。捕集1min,测得Bi、Ga、Sb的特征浓度依次为3.5×10-3、1.6×10-3、1.8×10-3μg·ml-1,它比常规火焰原子吸收光谱法的灵敏度分别提高254、131、239倍。Bi、Ga、Sb的变异系数各为2.9、3.5、4.7%。本法测定了纯锡中微量Bi、Sb。 相似文献
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《Analytical letters》2012,45(15):2513-2520
Slotted Quartz Tube (SQT) is a simple device that provides a sensitivity enhancement of 2–5 times in Flame Atomic Absorption Spectrometry (FAAS) depending on the element. A Gas Screen-Slotted Quartz Tube (GS-SQT) was designed to further increase sensitivity. For this purpose, two slotted gas chambers were fixed on the left and right sides of a burner head and Ar gas was supplied into these chambers perpendicular to the light path to produce two thin layers of gas screen. It was observed that these Ar screens can move up the flame tails in two ends of SQT. In addition to an increase in sensitivity by the use of SQT, Ar screen resulted in a further improvement in characteristic concentrations, C0, by a factor of 1.60 for Cd, 2.01 for Co, 1.42 for Cu, 1.94 for Mn, 1.86 for Ni, 1.78 for Pb, 1.62 for Se, and 1.09 for Zn. In addition to the enhancement in sensitivity, gas screen also helps by protecting the spectrometer from the adverse effect of using slotted quartz tube. The system is very simple and low-cost; it can be produced and applied easily. 相似文献
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原子吸收,原子荧光和火焰光谱分析 总被引:2,自引:0,他引:2
本文根据1988~1990年国内主要分析刊物所发表的文章,以及第三届北京分析测试学术报告会及展览会(BCEIA)、中国化学会第三届原子光谱会的主要论文,对我国原子吸收、原子荧光和火焰光谱分析的进展进行了评述,对于国外有关的重要文章也简单地加以介绍。 相似文献
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赵进沛 《广东微量元素科学》1995,2(3):33-36
采用自制原子捕集装置,选择了镉在不锈钢管上捕集的合适条件,使测镉的灵敏度比常规火焰原子吸收法提高了116倍。应用于工业废水中痕量镉的测定,获得满意结果。 相似文献
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《Analytical letters》2012,45(6):959-968
A simple device for the reduction of nonspectral interferences in flame atomic absorption spectrometry is proposed. It has been reported that the use of a gas screen (GS) system together with a slotted quartz tube (SQT) enhances the residence time of analyte atoms in measurement zone even more than the SQT alone. This combination causes enhancement of sensitivity and improves the reproducibility of absorbance measurements. In addition, it protects the optical windows of the atomic absorption spectrometer. The operational mechanism of gas screen is simply applying two argon gas walls at both ends of SQT to provide an environment that is partly protected from air. This action enhances the sensitivity of measurement. In this study, interference effects of excess amounts of calcium and chromium on the measurements of Cd, Co, Cu, Pb, Mn, Ni, Se, and Zn were studied using flame AAS. The presence of both Ca and Cr cause higher absorbance values; it is suggested that this is due to formation of oxide species of Ca and Cr and as a result analyte oxide production is suppressed. Therefore, analyte free atom population and sensitivity are enhanced. This enhancement results in a positive error in measurements. For instance, presence of solely 8.0 mg L?1 of Cr or Ca for Pb as the analyte enhances the signals by 75% and 56%, respectively. When SQT or GS-SQT is used, this effect is significantly reduced. 相似文献