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1.
In general, biological organisms have the ability to absorb a specific element selectively. Holcombe and his co-workers reported that copper, nickel and cobalt could be separated from riverine and sea-water samples and cadmium from river water samples by unicellular green algae and were determined by slurry GFAAS. Dar-  相似文献   

2.
石墨炉原子吸收光谱测定中碱土金属氯化物的背景吸收   总被引:2,自引:0,他引:2  
研究了石墨炉原子吸收中碱土金属氯化物在190~360nm范围的背景吸收,以及灰化温度和原子化温度对背景吸收的影响,讨论了背景吸收对测量的干扰,以及HNO3基体改进剂和氘灯扣除背景测量方式对背景干扰消除情况。  相似文献   

3.
石墨炉原子吸收光谱中海水的背景吸收研究   总被引:2,自引:0,他引:2  
由于海水的成分复杂,含盐量高,给用石墨炉直接测定其中的痕量杂质带来许多困难[1]。Sturgeon等用预先分离的方法来克服干扰[2]。为了进行直接测定,研究海水背景吸收的来源、特点和消除方法是重要的。海水背景吸收的波长特性和在石墨管内蒸发行为的研究表明,海水的背景吸收主要来自氯化钠。时间特性的研究表明,背景吸收的时间分布及背景峰高与原子化阶段的加热方式和原子化温度有关。作者还研究了基体改进。剂和其它减小背景吸收的方法。  相似文献   

4.
石墨炉原子吸收光谱中GdCl3,Gd(NO3)3基体的背景吸收   总被引:1,自引:0,他引:1  
研究了石墨炉原子吸收光谱中GdCl3、Gd(NO3)3基体的背影吸收影响。背景吸收波长特性的研究表明,GdCl3和Gd(NO3)3的背景吸收都具有明显的波长特性。蒸发行为研究表明GdCl3的背景吸收主要来自GdCl3的分子蒸气,Gd(NO3)3的背景吸收主要来自NO。钆基体的背景吸收峰高与灰化有关,GdCl3背上曲线轮廓与原子化温度和原子化方式有关。Gd(NO3)3的背景吸收远小于GdCl3。本文  相似文献   

5.
利用镥、镱基体在石墨炉中的蒸发行为研究了背景吸收的来源 ,讨论利用基体改进剂减少氯化物背景吸收的方法 ,为镥、镱基体中超痕量元素的精确测定提供帮助。  相似文献   

6.
俞志鹤  刘瑶函 《分析化学》1993,21(3):357-359
本文研制了一种新的原子吸收背景校正装置,将自吸效应校正背景吸收的光源和产生自吸分为两个部分,自吸在一个被称为自吸管的装置内发生,文章讨论了这种分离式自吸效应校正原子吸收背景的可行性及可能存在的优点,研制成的自吸管对铜、锌、铁、铬、镍空心阴极灯光源的自吸收达到一定的深度。  相似文献   

7.
《Analytical letters》2012,45(5):935-940
Abstract

The Disk-Ended Atomizer (DEA) is a technique for spatially isothermal atomization with an improved temporal isothermality of the atomization zone. It was developed at Sofia University as a continuation of our studies1,2 concerning one of the most important problems of graphite furnace atomic absorption spectrometry - the problem of isothermal atomization. DEA has a simpler design then many other techniques for isothermal atomization (L′vov cuvette3, Woodriff furnace4,5, capacitive discharge technique6, two-step furnaces2,7,8, etc.) and can be readily used with any commercial spectrophotometer.  相似文献   

8.
石墨炉原子吸收光谱法绝对分析   总被引:5,自引:0,他引:5  
石墨炉原子吸收光谱法(GFAAS)绝对分析近年来得到了较显著的发展,其主要原因是由于GFAAS中基体干扰问题获得了解决;用以描述GFAAS性能的特征质量MOE值相对稳定;以及用L’vov提出的计算MOT值的式子算出的32个元素的MOT值已比较接近其实验MOE值。大量数据表明完全有可能实现GFAAS绝对分析。  相似文献   

9.
润滑油、Tween80、1%硝酸溶液三种组分按1.5∶3∶21的体积比可形成稳定的微乳液.采用标准加入法,微乳液直接进样,石墨炉原子吸收光谱法测定润滑油中铜.进样量为20μL,对最佳原子化条件进行了试验.方法的精密度为5.1%,检出限为0.055mg.L-1,回收率为96.7%~105.0%.  相似文献   

10.
《Analytical letters》2012,45(7):1399-1408
ABSTRACT

The behaviour of thermally reduced or electrodeposited iridium modifier in graphite furnace atomic absorption spectrometry (GFAAS) for the determination of selenium was investigated. The performance of modification for standard solution of selenium as well as in the presence of chloride containing matrix (e.g. sea water) was examined. It was found that the graphite material plays a significant role in the determination of volatile elements by the formation of graphite intercalation compounds. Those compounds are responsible for the long-term performance of stabilisation of selenium in chloride containing solutions.  相似文献   

11.
原子吸收光谱分析中石墨炉的原子化效率   总被引:2,自引:0,他引:2  
郑衍生  衷明生 《分析化学》1995,23(4):378-382
本文基于石墨炉原子吸收信号与分析物原子数量间的关系导出了原子化效率公式;原子化效率测量值等于计量原子化效率值乘以τD/τR。采用V型舟测定了日立GA-3型石墨炉中Ag,Cd,Ge,In在各原子化温度时的β值、τR值以及它们的特征质量值。在研究的温度范围内除Ge外,τD/τR值没有明显的变化,因τR>τD导致ε>β,原子的消失过程影响差原子化效率。  相似文献   

12.
Selenium concentration in serum has been proposed as the most valuable indicator of human selenium status. In this work, the concentration of selenium in serum is measured by GFAAS using longitudinal Zeeman-effect background correction, a highly sensitive technique that can be used to determine selenium at sub-ppb level. Standard reference materials are analyzed to verify the accuracy and precision of this technique. The direct method proposed in this study is used for the determination of selenium in human serum collected from healthy people of 19–25 years and women of 21–34 years in the First trimester of pregnancy. The method developed in this study, which can quickly and accurately measure serum selenium, is suitable for applications in clinical diagnosis or biological monitoring.  相似文献   

13.
石墨炉原子吸收法测定美白化妆品中铅和镉   总被引:7,自引:0,他引:7  
本文采用石墨炉原子吸收法测定了美白化妆品中铅、镉含量.铅、镉测定的线性范围分别为0~176 ng/mL、0~88 ng/mL,相关系数r均为0.9998,回收率分别为98.2%~101.1%和98.9%~101.8%,相对标准偏差分别为1.73%和1.46%.  相似文献   

14.
《Analytical letters》2012,45(9):1993-2005
Abstract

Graphite furnace atomic absorption spectroscopic (GFAAS) analysis of oil samples from the onshore and offshore fields in the Niger Delta was carried out in order to determine their trace element contents. The concentrations of the elements (Cr, Co, Cu, Fe, Mn, Ni, Pb, and V) determined ranged from 0.151–941.199 ppb with an average of 30.190 ppb (% RSD<5) for the oil samples analyzed. The pattern of occurrence of each element was in agreement with studies conducted employing neutron activation analysis and flame atomic absorption spectroscopy. From the cluster analysis of the data, two groups of oils were evident. The groups are correlated with each other, indicating common or similar genetic origin. Trace metal parameters indicate that the oils were generated from organic matter of strong terrestrial input. GFAAS proved to be a good method for the analysis of elemental composition and classification of Niger Delta oils.  相似文献   

15.
影响石墨炉中特征量的某些因素研究   总被引:2,自引:0,他引:2  
原子吸收光谱分析发展过程中,绝对分析一直是人们所期望解决的问题。Slavin等发展的稳温平台石墨炉(STPF),以及测量积分吸光度,为绝对分析提供了有效的实验技术条件。L′vov等首先从理论上计算了元素特征量。Frech等曾指出石墨炉沿管长的温度梯度是限制绝对分析的一个重要因素。张展霞等考虑塞曼效应计算了一些元素的特征量理论值,Co、Cr和V的特征量实验值与理论值之比大于L′vov的结果。本文采用3种不同  相似文献   

16.
A micro-flow injection sorbent extraction preconcentration system was combined with a graphite furnace atomic absorption spectrometer. The combination results in an integrated system for the determination of trace amounts of heavy metals. Silica bonded with octadecyl functional groups (C18) was used as a sorbent in a 15-μL conical microcolumn. The metals to be determined were preconcentrated as diethyl dithiocarbamate chelates onto the column for 60 s and then rinsed with deionized water and eluted with 40 μL of ethanol. Compared with direct injection of 40 μL of aqueous sample solution, enrichment factors of 30, 32, and 29 and detection limits (3ς) of 7.8, 12.8, and 3.9 ng/L for cobalt, nickel, and lead, respectively, were obtained with 60-s sample loading at 3.0 mL/min for sorbent extraction, 40 μL of eluate injection, and peak area measurement. The results obtained for trace amounts of cobalt, nickel, and lead in reference materials showed that there were no significant differences between the certified and determined values.  相似文献   

17.
18.
使用形影不离碳材料作热解涂层石墨管的恒温平台,利用玻碳材料抗化学腐蚀能力强、使用寿命长和孔隙率低等特点,克服了玻碳管使用温度受电源装置的限制及影响中等蒸发元素测定等问题。初步研究了典型易蒸发元素Cd和中等蒸发元素Cu在玻璃平台上的分析性能;比较了不同规格玻璃碳平台与标准石墨平台间的差异以及它们之间抗基体干扰的能力;用扫描电子显微镜观察了它们的表面状态。  相似文献   

19.
报道了螯合树脂 PCON (N,N-二乙基胺基环硫丙烷交联壳聚糖)对银的分离、富集作用,富集物以悬浮液进样,石墨炉原子吸收法测定。结果表明PCON 螯合树脂用 5% 盐酸清洗后,在 pH11.0±0.2 范围内,富集效果高达 98.8±1.0% ,银的浓度在 0.2~2.0ng/mL 范围内,PCON 螯合树脂富集效率不受银量的影响,在超声波振荡下,4min 即达到富集平衡,本方法已用于自来水中痕量银的测定。  相似文献   

20.
参考GB/T 5009.12—2010标准方法,采用石墨炉原子吸收光谱法测定了螺旋藻中铅的含量。实验结果表明,铅的线性关系良好(R≥0.999 5),标准样品GBW10025测定值与标准值吻合,样品加标回收率测定数据良好(回收率92.6%),同时验证了前处理过程中赶酸操作和基体改进剂选择的重要性。方法方便可靠,数据准确,适合测定螺旋藻中铅的含量。  相似文献   

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