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1.
A determination method for lead in waste water and effluent was studied using flame atomic absorption spectrometry after preconcentration of lead by the rapid coprecipitation technique with gallium phosphate. Lead ranging from 0.5 to 50 microg was quantitatively coprecipitated with gallium phosphate from 100-150 mL sample solution (pH approximately 5). The presence of gallium phosphate did not affect the atomic absorbance of lead. Since the concentration of gallium in the final sample solution is also measurable by flame atomic absorption spectrometry at 250.0 nm without further dilution, the rapid coprecipitation technique, which does not require complete collection of the precipitate, becomes possible using a known amount of gallium and measuring the concentrations of both lead and gallium in the final sample solution by flame atomic absorption spectrometry. The 32 diverse ions tested gave no significant interferences in the lead determination. The method proposed here is rapid and has good reproducibility. 相似文献
2.
Shigehiro Kagaya Zanariah Abdul Malek Yasuko Araki Kiyoshi Hasegawa 《Analytical sciences》2002,18(8):923-926
By applying an internal standardization, we could use a rapid coprecipitation technique using lanthanum phosphate as a coprecipitant for preconcentration of iron(III) and lead in their flame atomic absorption spectrometric determination. Indium as an internal standard was added to the initial sample solution together with lanthanum and phosphoric acid; the coprecipitation of iron(III) and lead was then carried out at pH about 3. After measuring the atomic absorbances of iron, lead, and indium in the final sample solution, we determined the contents of iron(III) and lead in the original sample solution by using the internal standardization with indium. In this method, complete collection of the precipitate was not required after the coprecipitation of iron(III), lead, and indium, because the ratio of the recovery of iron(III) or lead to that of indium was almost constant regardless of the recovery of the precipitate. This method was simple and rapid, and was available for the determination of 2-300 micrograms L-1 of iron(III) and 5-400 micrograms L-1 of lead in some water samples. 相似文献
3.
Xiaobin Hu 《International journal of environmental analytical chemistry》2013,93(3):263-271
A coprecipitation technique which does not require complete collection of the precipitate was proposed for the determination of trace lead and cadmium in water with flame atomic absorption spectrometry (FAAS) after preconcentration of lead and cadmium by using cobalt (II) and ammonium pyrrolidine dithiocarbamate (Co-APDC) as coprecipitant and known amount of cobalt as an internal standard. Since lead, cadmium and cobalt were well distributed in the homogeneous precipitate, the concentration ratio of lead to cobalt, and cadmium to cobalt remained unchanged in any part of the precipitate. The amount of lead and cadmium in the original sample solution can be calculated respectively from the ratio of the absorbance values of lead and cadmium to cobalt in the final sample solution that is measured by FAAS and the known amount of the lead and cadmium in the standard series solutions. The optimum pH range for quantitative coprecipitation of lead and cadmium is from 3.0 to 4.5. The 16 diverse ions tested gave no significant interferences in the lead and cadmium determination. Under optimised conditions, lead ranging from 0 to 40?µg and cadmium ranging from 0 to 8?µg were quantitatively coprecipitated with Co-APDC from 100?mL sample solution (pH?~?3.5). This coprecipitation technique coupled with FAAS was applied to the determination of lead and cadmium in water samples with satisfactory results (recoveries in the range of 94.0–108%, relative standard deviations <6.0%). 相似文献
4.
A continuous precipitation and filtration flow system for the separation of citric acid by precipitation with lead and indirect
flame atomic absorption spectrometry is proposed. The precipitate is formed by injecting the lead solution into a carrier
containing the sample and is subsequently retained on a filter. By using this reversed precipitation flow-injection configuration,
citric acid was determined in the range 2–40 μg mL–1, with a relative standard deviation of 2.9% at a sampling frequency of 60 samples h–1. This method has been applied to the determination of citric acid in fruit juices, carbonated soft drinks and sweets.
Received: 19 March 1999 / Revised: 27 May 1999 / Accepted: 31 May 1999 相似文献
5.
Determination of lead traces in water and liqueurs by derivative atom trapping flame atomic absorption spectrometry 总被引:3,自引:0,他引:3
H. Sun Li-li Yang De-qiang Zhang Wei-Xiao Wang Jian-min Sun 《Fresenius' Journal of Analytical Chemistry》1997,358(5):646-651
A new method for the direct determination of lead traces using derivative atom trapping flame atomic absorption spectrometry
(DAT-FAAS) with an improved water-cooled stainless steel trapping equipment in an air-acetylene flame was investigated. The
optimum conditions concerning the sensitivity were studied. For a 1 min collection, the characteristic concentration (given
as derivative absorbance of 0.0044) and the detection limit (3s) were 1.4 ng/mL and 0.27 ng/mL, respectively. This is 361
and 74-fold better than those of the conventional flame atomic absorption spectrometry (FAAS) and comparable to those of graphite
furnace atomic absorption spectrometry (GFAAS). The detection limit and sensitivity of DAT-FAAS for a 3 min collection time
were 2 and 3 orders of magnitude higher than those of conventional FAAS. The present method was applied to the determination
of lead in water and liqueur samples with a recovery range of 94–108% and a relative standard deviation of 3.5–5.6%.
Received: 10 January 1996/Revised: 9 December 1996/Accepted: 20 December 1996 相似文献
6.
The sensitivity of traditional flame atomic absorption spectrometry (FAAS) is low for the determination of lead. Therefore,
a simple branched capillary was used for hydride generation with air-acetylene FAAS determination of lead in geochemical samples
and paint. Using a Y-shaped connector, the sampling capillary of a traditional FAAS instrument was branched, with one branch
for introducing the reductant solution, KBH4, and the other for the sample solution, Pb4+. The KBH4 solution and the Pb4+ solution were then merged and mixed inside the reaction capillary and thereafter inside the nebulizer for generating the
lead hydride, which, together with the liquid fine droplets, was directly brought into the air-acetylene flame for atomization
without gas/liquid separation. The experimental conditions were optimized for best signal-to-noise ratio (S/N). A calibration
curve was obtained with a linear dynamic range of up to 1.0 mg L−1 and a correlation coefficient of 0.9997. The limit of detection (LOD) for lead was found to be 0.004 mg L−1, 10 times better than that of traditional FAAS and slightly better than or equivalent to that of the sophisticated inductively
coupled plasma atomic emission spectrometry (ICP-AES). The improvement in sensitivity and the LOD for lead largely owe to
the altered atomization mechanism via hydride generation. The proposed method was successfully applied to the determination
of lead in Geochemical Standard Deposit (GSD) samples and paint samples. 相似文献
7.
Ümit DivrikliLatif Elçi 《Analytica chimica acta》2002,452(2):231-235
A cerium(IV) hydroxide coprecipitation method was developed for the determination of some trace elements (Cu, Co, Pb, Cd, Ni) in aqueous solutions, water and sediment samples by flame atomic absorption spectrometry (AAS). Several parameters governing the efficiency of the coprecipitation method were evaluated including pH of sample solution, amount of carrier element, volume of sample solution and the effect of possible matrix ions The procedure was validated by the analysis of GBW 07309 standard reference material sediment and by use of a method based on a solid phase extraction. 相似文献
8.
A continuous flow atomic absorption spectrometric system was used to develop an efficient on-line preconcentration-elution
procedure for the determination of iodide traces. Chromium (VI) is introduced into the flow system and is reduced to chromium
(III) in acid medium proportionally to the iodide present in the sample. The Cr(III) reduced by iodide is retained on a minicolumn
packed with a poly(aminophosphonic acid) chelating resin, while unreduced Cr(VI) is not retained. Reduced Cr(III) is preconcentrated
by passing the sample containing iodide through the system during 3 min, and is then eluted with 0.5 mol L–1 hydrochloric acid and determined by flame atomic absorption spectrometry (FAAS). The detection limit (3σ) obtained is 2.5
μg L–1. Other ions typically present in waters do not interfere. The proposed method allows the determination of iodide in the range
6–220 μg L–1 with a relative standard deviation of 2.7% at a rate of 17 samples h–1. The method has been applied to the determination of iodide in tap and sea waters.
Received: 16 September 1999 / Revised: 15 November 1999 / Accepted: 19 November 1999 相似文献
9.
10.
A method for determination of trace amounts of Cu, Fe, Pb, Mn, Zn, Cd, Ni, Bi and Cr in aqueous solutions by flame atomic absorption spectrometry after coprecipitation by using a combination of sodium diethyldithiocarbamate as a chelating agent and cobalt as a carrier element was introduced. Different factors including amounts of reagents, pH of sample solution, standing time, sample volume for the precipitation and matrix effects were examined. Under selected conditions, the relative standard deviation of the combined method of sample treatment, coprecipitation and determination with flame AAS (n = 9) is generally about 3.5-6.9%; the limits of detection (3 s, n = 20) for the analytes were found to be between 4 and 64 microg 1(-1). The procedure was applied to the analysis of sea water and dialysis concentrate samples with quantitative recovery, > or =95%. 相似文献
11.
Mitra Talaee Majid Ramezani Mehrdad Cheraghi Saeed Jameh-Bozorgi 《International journal of environmental analytical chemistry》2013,93(12):1235-1246
ABSTRACTTandem dispersive liquid liquid microextraction coupled with micro - sampling flame atomic absorption spectrometry for rapid determination of lead2 and cadmium2 ions in environmental water samples. A simple method termed as tandem dispersive liquid–liquid microextraction coupled with micro-sampling flame atomic absorption spectrometry is used for determination of the lead(II) and cadmium(II) ions in different environmental water samples. According to the proposed method, the target analytes are extracted from an aqueous sample solution (10 mL) into a micro-volume of an organic solvent, and then they are selectively back-extracted into an aqueous acceptor solution (150 μL) to increase the compatibility of the extractant phase with a final analyser system and provide a suitable enrichment factor. The developed method is very fast, implemented in just about 7 min, and provides a high sample clean-up. The factors influencing the extraction efficiency including the type and volume of the organic solvent, pH and volume of the acceptor solution, and number of extractions are thoroughly examined and optimised. Under the optimal experimental conditions, the developed method provides a good linearity (in the range of 0.4–300 ng mL?1 (R2 ≥ 0.994)), and low limits of detection (in the range of 0.07–0.31 ng mL?1). Finally, the method is successfully applied for the direct determination of the understudied analytes in the river, dam, and well water samples. 相似文献
12.
原子吸收法测定血清中的无机磷和钙 总被引:1,自引:0,他引:1
本文叙述了用原子吸收法测定同一个少量血清样品中的无机磷和钙。血清用高氨酸沉淀蛋白后,加过量钼酸铵。在pH0.4~1.6范围内,用乙酸丁酯萃取生成的微量磷钼酸,与过量的钼酸铵分离。水相测钙,有机相用稀氨水反萃后测钼,间接分析磷。 相似文献
13.
The suitability of 1-nitroso-2-naphthol as a complexing agent for on-line preconcentration of copper using RP-C18 material in a microcolumn with flow injection coupled with flame atomic absorption spectrometry (FI-FAAS) has been tested.
Various parameters affecting complex formation, such as pH, sample flow rate, etc. and its elution into the nebulizer of FAAS
were optimized. ?A 5 × 10–3 mol/L reagent was on-line mixed with aqueous sample solution acidified with 0.1% (v/v) nitric acid ?(pH 3–4) and flowed through
the microcolumn for 30 s. The adsorbed complexes in the microcolumn were eluted with ethanol in 10 s into the nebulizer of
FAAS. A good precision (1.7% for 50 μg/L copper, n = 12), high enrichment factor (19) with detection limit (3σ) 2.0 μg/L,
and sample throughput (90 h–1) were obtained. The method was applied to certified reference materials seawater, mussel (biological), NBS-362 and NBS-364
(special low alloy steel), for the determination of copper, and the results were in good agreement with the certified values.
Received: 4 May 1999 / Revised: 25 June 1999 / Accepted: 29 June 1999 相似文献
14.
15.
B. Boppel 《Analytical and bioanalytical chemistry》1974,268(2):114-119
Some possible errors are pointed out, which can occur in the determination of lead and a method is described which minimizes these errors. The loss of lead during the dry-ashing-procedure was determined in dependence on the temperature in the sample measured by immersed thermocouples. It is not advisable to transfer ashing data from one foodstuff (e.g. vegetable) to foodstuffs of different composition (e.g. meat); such data must be determined experimentally. Many matrix elements in ash solutions influence the lead determination by atomic absorption spectroscopy. By H2S coprecipitation of lead and added silver ions as PbS/Ag2S this disturbance can be avoided and the lead concentration is simultaneously increased. With the aid of a nitrate-carbonate melt before the H2S coprecipitation the residual carbon of the ash is removed and acid-insoluble compounds are made accessible. The use of hydrofluoric acid for destroying the silicates, which is disadvantageous, can thus be omitted. The lead content in the final solution is determined in an atomic absorption spectrometer by comparison with a standard solution of appropriate concentration. 相似文献
16.
火焰原子吸收光谱法测定水样中铅含量的不确定度评定 总被引:3,自引:1,他引:2
通过采用火焰原子吸收光谱法测定水样中铅的不确定度各项来源和评定方法的分析,建立一种分析实验室不确定度的评定方法,使实验结果更有客观性和准确性. 相似文献
17.
A mixture of manganese dioxide and hydrochloric acid has been used for the accurate and precise determination of gold in
various gold-bearing matrices. Results of intermethod comparison studies, F-test on variances, Mann-Whitney U-test, Spearman
rank correlation and regression analyses are presented. The recommended method can be applied to a quality control programme
and for the evaluation of reference materials. Various standard reference materials (SRM) of diverse matrices have been examined
to check the validity of the method and the results were found to be in very good agreement with the certified data. Sample
decomposition is straight forward [1–10 g sample (roasted at 600–700 °C)+5 g of MnO2+30 mL of 2 mol/L HCl]. Gold is coprecipitated with potassium tellurite using tin (II) chloride solution. The precipitate
is extracted into toluene and finally stripped back into aqua-regia solution for final nebulization into an air-acetylene
flame for atomic absorption spectrophotometry. The method is very simple and easily adaptable, and more convenient than conventional
methods involving aqua regia or a hydrobromic acid-bromine water mixture.
Received: 23 October 1995/Revised: 18 March 1996/Accepted: 23 March 1996 相似文献
18.
A sensitive and selective flow injection time-based method for on-line preconcentration/separation and determination of gallium by flame atomic absorption spectrometry at trace levels was developed. The on-line formed gallium chloride complex is sorbed onto a polyether-type polyurethane foam mini-column, followed by on-line quantitative elution with isobutyl methyl ketone and direct introduction into the flame pneumatic nebulizer of the atomic absorption spectrometer. All chemical and flow variables of the system as well as the possible interferences were studied. The manner of strong HCl solutions propulsion was investigated and established using a combination of two displacement bottles. For 90 s preconcentration time, a sample frequency of 28 h−1, an enhancement factor of 40, a detection limit of 6 μg l−1 and a precision expressed as relative standard deviation (sr) of 3.3% (at 1.00 mg l−1) were achieved. The calibration curve is linear over the concentration range 0.02-3.00 mg l−1. The accuracy of the developed method was sufficient and evaluated by the analysis of a silicon-aluminum alloy standard reference material. Finally, it was successfully applied to gallium determination in commercial aluminum alloys, natural waters and urine. 相似文献
19.
建立了火焰原子吸收光谱法测定高铋铅中铜含量的方法。研究了多种溶样方法,最终采用硝酸-酒石酸溶解试样,在硝酸(10%)介质中以火焰原子吸收光谱法测定溶液中的铜量,加标回收率在99.4%~105%,相对标准偏差(RSD,n=7)小于3.5%。方法操作过程简单,精密度高,回收率良好,能够较好地满足分析检测的要求。 相似文献
20.
Determination of the metal content of sewage sludges is of increasing importance in order to assess the suitability of the sludge for disposal to agricultural land. The methods currently used for the determination of cadmium, chromium, copper, nickel, lead and zinc are time-consuming. A rapid electrothermal atomic absorption procedure with homogenization as the only pretreatment is compared with wet and dry pretreatment methods followed by flame atomic absorption spectrometry, in a statistically designed experiment. The precision of the rapid electrothermal atomic absorption procedure compares well with flame atomic absorption in conjunction with all pretreatment methods used. Time saved by the use of this method is substantial; the procedure could be used advantageously for routine analysis. 相似文献