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1.
《Analytical letters》2012,45(15):2701-2712
Abstract

Arsenic (III), arsenic (V), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) were separated by ion-exchange chromatography. The elution sequence was as follows: 1.5 M ammonia followed by 0.12 M hydrochloric acid yielding As(III) 1 M hydrochloric acid followed by water yielding first As(V) and then MMA. Detection was by hydride generation-atomic absorption spectrometry. No interference was noted from 13 metallic ions.

The method provides a good linearity, precision, accuracy, and sensitivity. It has been applied to the speciation of arsenic in seawaters from the North West coast of Spain (1200 Km).  相似文献   

2.
建立了石墨炉原子吸收光谱(GFAAS)法测定生活饮用水中砷的方法。升压放电空心阴极灯的使用,降低了基线噪声水平和检出限。对温度程序、化学基体改进剂和热稳定剂进行了优化并用于GFAAS测定砷,无需进行初步处理。研究结果显示,线性方程为y=0.005 62x+0.000 04,相关系数R为0.998 3,样品体积为16μL时的检出限为0.26μg/L。加标回收率为98.1%~99.2%,相对标准偏差5%。取实际饮用水样验证了其适用性。  相似文献   

3.
建立了石墨炉原子吸收光谱(GFAAS)法测定生活饮用水中砷的方法。升压放电空心阴极灯的使用,降低了基线噪声水平和检出限。对温度程序、化学基体改进剂和热稳定剂进行了优化并用于GFAAS测定砷,无需进行初步处理。研究结果显示,线性方程为y=0.005 62x+0.000 04,相关系数R为0.998 3,样品体积为16μL时的检出限为0.26μg/L。加标回收率为98.1%~99.2%,相对标准偏差<5%。取实际饮用水样验证了其适用性。  相似文献   

4.
陈甫华  卫红梅 《分析化学》1993,21(7):761-764
砷酸盐(As(Ⅴ))、亚砷酸盐(As(Ⅲ))、甲基胂酸盐(MMAA)和二甲基胂酸盐(DMAA),是天然水中砷的主要存在形态。本文用离子色谱分离这些砷形态,继以KBH_4还原、原子吸收法检测。分离用国产YSA-Ⅱ型阴离子交换色谱柱来完成。按上述砷形态的顺序,检出限以砷计是0.8μl、0.2μl、0.4μl和0.4μg/L。湖水样及市售矿泉水样的加标回收率为93.2%~107.5%。给出上述水样中砷形态的分析结果。  相似文献   

5.
《Analytical letters》2012,45(5):357-369
Abstract

The determination of the arsenic content of foods and beverages by a technique involving a magnesium nitrate aided dry ashing step followed by an arsine generation atomic absorption finish is described. Recoveries of various arsenic species added prior to ashing was excellent. Total arsenic concentrations found in samples of beverages ranged from less than 10 to 265 ppb and in foods from 20 to 9290 ppb. The sensitivity of the technique is approximately ten-fold better than obtainable with commercially available hydride generation atomic absorption units.  相似文献   

6.
《Analytical letters》2012,45(7):449-459
Abstract

Two atomic absorption accessory units were studied for the determination of arsenic and selenium in waters. One involves a flame mode while the other a flameless mode. Each was analyzed for requirements in speed per analyses, sample sizes required, potential interferences, coefficients of variation, and in overall ease in use.

Although the flameless mode could determine lower levels of arsenic and selenium than the flame mode, it was hampered by some severe interferences. Advantages of these accessories in their use over conventional wet chemical methods included: speed per analysis, elimination of time-consuming concentration steps, and elimination of using fragile equipment and noxious solvents.  相似文献   

7.
本文研究了用萃取分离环境样品中的有机砷和无机砷,用氢化物发生ICP-AES法测定的方法。As(Ⅲ)、As(Ⅴ)、DMA、MMA检测限在0.6~0.8ppb之间。各形态砷的浓度在1ppb~10ppm之间时工作曲线呈良好线性关系,相对标准偏差为1.4~2.2%。  相似文献   

8.
本文提出用乙醇作为 NaBH_4的溶剂,APDC-MIBK 有机相氢化物发生原子荧光光谱法测定饮用水中砷。与 DMF 相比,乙醇溶剂具有价廉、无毒性以及荧光背景小,可以在较低酸度下发生氢化物的特点。对非水介质氢化物发生法的推广应用具有较大的实用价值。  相似文献   

9.
介绍简易的氢化物发生原子吸收测砷的方法。喷雾器负压将KBH_4吸入反应器,并将生成的AsH_3吸入乙炔-空气焰原子化。石英缝管使灵敏度提高3.5倍。方法的检测限(3σ)为1.8ng/mL(5mL试样)。20ng/mLAs(Ⅲ)标准液10次测定的RSD为3.8%。本法成功地应用于钢铁和地质标样中微量砷的测定。  相似文献   

10.
氢化物—原子荧光光光谱法同时测定黄铜中的砷与锑   总被引:4,自引:1,他引:4  
试样用硝酸-硫酸分解,试验了酸度、还原剂浓度以及黄铜中常见元素对测定结果的影响,砷、锑的回收率分别为:96%~109%,90%~93%,砷、1锑的检出限分别为0.19ng=mL、0.31ng=mL,砷、锑的线性范围分别为0.5~250ng/mL、0.5~500ng/mL。本法用于黄铜标准样品中的砷、锑。结果与标准值吻合。  相似文献   

11.
本文建立了微波辅助提取-氢化物发生-原子荧光光谱法测定服用有机砷饲料后猪排泄粪便中的无机砷和有机砷的方法.研究了微波辅助提取的最佳条件,考察了酸介质、还原剂的选择及共存离子的干扰及消除方法.方法的检出限为0.20 μg\5L-1,相对标准偏差(RSD)为1.3%,样品加标回收率为95.2%~97.2%.  相似文献   

12.
《Analytical letters》2012,45(7-8):1172-1189
The purpose of this study consists in reporting of single laboratory validation of a method for the determination of total inorganic arsenic by hydride generation atomic absorption spectrometry from natural and residual water samples. Applicability, fitness for purpose, selectivity, and sensitivity were discussed. A calibration study was realized, linear working range (0.4–4 μg·L?1), detection (0.11 μg·L?1), and quantification (0.38 μg·L?1) limits being determined. It was also proven that the method is accurate and precise. Following the bottom-up approach measurement, uncertainty was estimated (method validation data were used).  相似文献   

13.
Analytical methods for the determination of inorganic arsenic species have attracted much attention due to the high toxicity of these compounds and related legislative regulations for food. A new method for the separation and quantitation of As(III) and As(V) was developed using ion-exchange membranes and laser-induced breakdown spectroscopy (LIBS). Using the anion-exchange polymer membrane, As(V) was selectively collected on the membrane, and As(III) was filtered through the membrane. The separated As(V) on the membrane was directly determined by LIBS. The As(III) in the filtrate was subsequently oxidized to As(V) and collected by the membrane for LIBS analysis. The detection limit for As(V) was estimated to be 10?mg/kg. The recovery efficiencies for the arsenic species as standards were in the range of 97–99%. This method was applied for the analysis As-spiked water certified reference materials, and the results showed that the recovery for As(V) was 98.9%. This new speciation method is cost-effective, simple, and low labor-intensive for the quantitation of inorganic arsenic.  相似文献   

14.
《Analytical letters》2012,45(6):449-459
Abstract

An analytical method has been developed to specifically monitor cis-dichlorodiammineplatinum (II) in plasma. The drug is separated from plasma protein and other macromolecular species by centrifugal ultrafiltration, which removes components with molecular weight greater than 50,000. The ultrafiltrate was then fractionated by HPLC. Mixtures were chromatographed on a strong anion exchange column and the eluent monitored spectrophotometrically (at concentrations of analyte exceeding 1μg/ml) or by atomic absorption spectrometry. Using the latter readout system, the detected limit for the analyte was 4 0 ng/ml of plasma at the 2s level and the detector output was linearly related to the drug concentration over the range 40–1000 ng/ml. The method appears to specifically respond to parent drug and is able to differentiate between it and other platinum species (metabolites or breakdown products) which may be present in the sample.  相似文献   

15.

A method is presented for arsenic speciation analysis of an oyster sample using ion chromatography coupled with an inductively coupled plasma mass spectrometry (ICP-MS) instrument. A strong anion exchange resin was employed with a step gradient elution of 0.1 mM/0.1 M K 2 SO 4 at pH 10.2. Arsenobetaine and dimethylarsinic acid were determined following extraction based on trypsin enzymolysis with 95-100% extraction efficiency. Limits of detection in the range 0.1-0.3 mg kg m 1 of arsenic were obtained for organic arsenic species. No inorganic arsenic was detected. Validation was performed using TORT-2 as a certified reference material. Although high performance liquid chromatography (HPLC) coupled to ICP-MS is an effective method for speciation analysis it is not always necessary to obtain such a detailed picture. A simple liquid chromatographic separation technique based upon mini-column technology is presented. It was developed to obtain a fast, efficient and reliable separation of inorganic from organic, i.e. assumed toxic from non-toxic, arsenic and selenium species suitable for use as an initial screening method for environmental analysis. Two types of strong anion exchange resin were tested. Excellent separation was obtained for both min-column resins and analysis times were within 7 min. Limits of detection obtained for inorganic arsenic, organic arsenic, selenomethionine, Se IV and Se VI were 1.6, 1.8, 66, 32 and 22 µg kg m 1 , respectively.  相似文献   

16.
本文对标准参考物质贻贝和虾粉中砷和硒的测定作了较详细研究。用 HNO_3-HClO_4常压、HNO_3-HClO_4-HF 常压,HNO_3-HClO_4-HF 加压和王水-HClO_4加压消解四种样品处理方法的测定结果表明,前两种方法不能将有机物完全破坏,从而使砷和硒的测定结果偏低。用加压消解方法可使样品中的有机物基本破坏完全,砷和硒的测定结果与标准值基本吻合。本文还对高价氢化物元素的预还原等问题作了讨论。  相似文献   

17.
《Analytical letters》2012,45(15-16):1573-1590
Abstract

A direct flow injection flame atomic absorption spectrometry method of determining zinc salt solutions with concentrations of 100's g dm?3 is reported. It was shown that high concentrations of KCl, NaCl and NH4Cl do not significantly interfere with the determination of zinc in both the mg dm?3 and g dm?3 concentration ranges. Where g dm?3 concentrations were determined a secondary spectral line at 307.6 nm was found satisfactory. Galvanizing preflux solutions were analyzed both after dilution to the mg dm?3 range at 213.9 nm and directly injected at 307.6 nm. Precisions of better than 6.6% rsd were observed by the direct method compared with better than 4.8 by dilution techniques. Concentrations up to 110 g dm?3 in zinc were determined the total salt content being greater than 300 g dm?3.  相似文献   

18.
利用电磁感应加热原理,研制了在线消化还原、氢化物发生原子荧光法分析装置,实现了茶水中As量的在线测定.对各种实验参数和干扰情况进行了研究.方法的检出限为0.063 μg/L;样品分析精密度(RSD)为2.5%(n=11).  相似文献   

19.
郭华明  刘春华 《分析化学》2012,(7):1092-1097
利用醋酸型AG 1-X8阴离子交换树脂和氯化物型AG 1-X8阴离子交换树脂对As(Ⅴ)和As(Ⅲ)吸附的差异,实现As(Ⅲ)和As(Ⅴ)的有效分离。过滤和酸化后的水样流经树脂交换柱(75mm×5.3mm i.d.)时,醋酸型AG 1-X8阴离子交换树脂可吸附As(Ⅴ);而As(Ⅲ)可通过树脂柱。被吸附的As(Ⅴ)用0.12mol/L HCl淋洗出来,在此过程中醋酸型树脂转化为氯化物型树脂。该树脂交换柱可多次循环使用。本方法简单易行,适用于野外现场条件下高砷地下水中As(Ⅲ)和As(Ⅴ)的分离和准确测定;用于检测水铁矿除砷过程中砷价态变化。结果表明,缺氧条件下水铁矿对As(Ⅲ)和As(Ⅴ)的吸附动力学特征遵循假二级反应动力学模式,内扩散不是控制As(Ⅲ)和As(Ⅴ)吸附的因素。随着时间的推移,膜扩散对吸附的控制作用增强。  相似文献   

20.
荧光分析中偶氮试剂的研究与进展   总被引:13,自引:5,他引:13  
李志良  石乐明 《分析化学》1990,18(8):780-790
  相似文献   

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