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《Analytical letters》2012,45(3):593-606
Abstract A solid chelating compound phenanthrenequinone monoxime PQM) supported on naphthalene provides a rapid and economical means of preconcentration and separation of copper from the aqueous samples. Copper forms a complex with PC:: supported on naphthalene in the column at pH 6.1–8.4 with a flow rate of 1 ml/min. The metal complex and naphthalene are dissolved out from the column with 5 ml of DMF and the absorbance is measured at 470 nm against reacent blank. Beer's law is obeyed in the concentration range 0.6 9.6 μg of copper in 5 ml of DMF. The molar absorptivity and sensitivity are 6.3×104 L mol?1 cm?1 and 0.001 μg cm?2 respectively. 相似文献
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《Analytical letters》2012,45(8):1645-1654
ABSTRACT|A highly selective, sensitive, rapid and simple atomic absorption spectrometric method has been developed for the determination of trace amounts of palladium in synthetic and real samples. Palladium can be adsorbed on naphthalene-1, 5-diphenyl-carbazone (DPCO) as adsorbent from the large volume of its aqueous solutions in the pH range 2.0 to 0. After filtration, the metal ion was desorbed with 5ml of 0.25M thiourea solution, and determined by AAS. Alternatively, palladium can be adsorbed on this adsorbent packed in a column and determined similarly. The detection limit is 0.5 μg (signal to noise ratio=2) and the linearity is maintained in concentration range of 1.5-50μg of Pd with a correlation coefficient of 0.9992. Seven replicate determinations on samples containing 2.5 and 20μg of palladium gave the relative standard deviations of 3.6% and 0.81%, respectively. Various parameters such as effect of pH, volume of aqueous phase, shaking time and interference of number of ions on the determination of Pd have been studied in detail to optimize the conditions for its estimation in various synthetic and real samples. 相似文献
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A solid‐phase extraction method for preconcentration of silver and consequent determination by atomic absorption spectrometry is described. The method is based on the adsorption of silver on naphthalene modified with dithizone in a column. The adsorbed silver is eluted from the column with a thiourea solution and determined by flame atomic absorption spectrometry. The adsorption conditions including pH, reagent concentration, eluent volume, flow rate and interfering ions were investigated. The calibration graph was linear in the range 10–1000 ng mL?1 of Ag in the initial solution with r = 0.9998. The limit of detection based on 3Sb was 3.9 ng mL?1. The relative standard deviation for ten replicate measurements of 40 and 600 ng mL?1 of Ag was 4.4% and 0.9%, respectively. The method was applied to the determination of silver in mineral, radiology film and wound dressing samples. 相似文献
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This work aims to achieve a determinate characterization of compound formation and to find out the resolution to overcome chemical interferences in atomic absorption spectrophotometric (AAS) determination of palladium. The effect of flame composition in producing a neutral palladium atoms was investigated. A new analytical procedure has been elaborated for the determination of palladium. 相似文献
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Critical Study of the Determination of Palladium by Graphite Furnace- Atomic Absorption Spectrometry
《Analytical letters》2012,45(7):535-552
Abstract The atomic absorption spectroscopic behaviour of palladium in a graphite furnace has been investigated. The determination is several ordes of magnitude more sensitive than the flame technique. The use of Tantalum coated tubes does not improve considerably the sensitivity but prolongs the lifetime of the furnaces. 相似文献
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流动注射在线萃取—石墨炉原子吸收光谱法测定地质样品痕量钯 总被引:12,自引:6,他引:6
应用流动注射在线萃取技术将PdCl^2-6萃入2-巯基苯并噻唑-甲基异丁基酮直接进行石墨炉原子吸收测定。研究了流动注射在线萃取-石墨炉原子吸收光谱法测定地质样品中钯的实验条件、流路参数等。采样速率为20样/h,RSD(n=10)为4.8%,测定Pd的特征质量为2.6*10^-11。 相似文献
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用X线荧光衍射法和原子吸收光谱法测定油漆中的铅含量 总被引:5,自引:0,他引:5
为勘查环境铅暴露的来源并评价其状况,应用K层X线荧光衍射法(XRF)对84张木制桌面表面油漆中的铅含量进行了测定。并应用原子吸收光谱法定量分析了8类18种液体油漆及12种内墙剥脱涂料中可溶性铅的含量。结果发现:所有桌面油漆的铅含量≤0.7mg/cm2,在正常范围内。但是,90年代以前生产的木质桌面表面油漆层中的铅含量明显高于90年代生产产品。液体油漆中铅含量为1.03×10-6~32800×10-6,其中超标者有3种,占16.7%,均为用于金属表面的防锈漆。内墙剥脱涂料中的铅含量为105×10-6~1430×10-6,均在正常范围内。结果提示:①应用便携式XFR检测桌面油漆中的铅含量,是一种快速、实用、准确的方法,非常有利于进行铅源的实地勘查;②除了少数几种工业用防锈漆以外,民用油漆,包括内墙涂料、家具、地板及桌面上用的油漆中的铅含量均未超标。但由于本调查未涉及80年代及更早时期的木质家具,老建筑中使用的油漆的铅污染情况如何,还有待进一步地勘查和研究。 相似文献
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《Analytical letters》2012,45(5-6):473-484
A novel sequential injection on-line column preconcentration method for ultra-trace cobalt determination by electrothermal atomic absorption spectrometry (ETAAS) using poly(etheretherketone) (PEEK) turnings as sorbent material was developed. The method was based on the on-line chelate complex formation and retention of target analyte with ammonium pyrrolidine dithiocarbamate (APDC) on the surface of PEEK-turnings and elution with methyl isobutyl ketone (MIBK). A 40 µL fraction of MIBK containing the bulk of analyte complex introduced directly into the transversely heated graphite tube atomizer of ETAAS for quantification. Acidity of sample solution, chelating reagent concentration, and preconcentration time were investigated and optimized separately, while all other factors were optimized by full factorial design optimization methodology. The significance of the variables and their interactions was estimated by employing analysis of variance (ANOVA) and Pareto chart. Under the optimum conditions the enhancement factor for cobalt determination was 60. The detection limit was 6 ng L?1 and the precision expressed as relative standard deviation (RSD) was 3.5% at 0.1 µg L?1 Co(II) concentration level, respectively. The proposed method was evaluated by analyzing water certified reference materials and spiked environmental samples. 相似文献
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《Analytical letters》2012,45(5):876-885
A solid phase extraction and graphite furnace atomic absorption spectrometry for the determination of palladium with MCI GEL CHP 20P resin as sorbent was studied. Trace amounts of palladium was reacted with 2-ethylhexyl octyl sulfide followed by adsorption onto MCI GEL CHP 20P solid phase extraction column, and ethanol was used as eluent. The enrichment factor of this method for palladium was reached at 250. The detection limit in the original sample for palladium was found to be 0.0048 ng mL?1. The proposed method has been successfully applied to the determination of trace amounts of palladium in different samples. 相似文献
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《Analytical letters》2012,45(5):251-257
Abstract By the combined use of the absorption tube technique and solvent extraction, determination of cadmium, cobalt, copper, iron, lead and nickel in silicate rocks was investigated. Applicable concentration range was from 0.1 to 1.Oppm for all the elements except cadmium, for which the range was from 0.005 to 0.025ppm. The accuracy and recovery determined by the use of standard samples from the United States National Bureau of Standards and Geological Survey were satisfactory for practical purposes. 相似文献
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《Analytical letters》2012,45(7):1409-1424
ABSTRACT|A direct method with graphite furnace atomic absorption spectrophotometry for determining low lead (Pb) levels in urine was described. The present method was based on wet-ashing digestion, 2-fold concentrated urine, and matrix modification with palladium chloride (PdCl2). The sensitivity (concentration at 0.0044 absorption units) of the proposed method is 0.18 ppb. Results were presented on the degree of accuracy and precision. Accuracy of the proposed method was checked by comparison with the values determined by the extracted method (conventional method). Precision of the proposed method was evaluated by within-run and between-run precision. Both of them were found to be satisfactory. Due to the high sensitivity, the proposed method could be applied to determine urinary Pb concentration in normal populations with no known Pb exposure. Moreover, the method is simple, fast, and automatic. 相似文献
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