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1.
Irina Karadjova 《Mikrochimica acta》1999,130(3):185-190
Methods are described for the determination of trace and ultra trace amounts of Cd, Co, Cr, Cu, Fe, Mn, Ni and Pb in natural waters, alkali and alkaline earth salts. Separation and preconcentration of trace metals is achieved by a column solid phase extraction procedure using silica gel modified with derivatives of dithiocarbamates — Na-DDTC (sodium diethyldithio-carbamate and HMDTC (ammonium hexamethylene-dithiocarbamate) as column packing material. The influence of the sorbent preparation procedure on the degree of sorption of the trace analytes is examined for different pH values of the sample solution. Isobutylmethyl ketone (IBMK) is proposed as an effective eluent for quantitative elution of retained metal ions. Optimal instrumental parameters for ETAAS determination of preconcentrated elements in organic eluate are presented. Practical application of sorbents in analysis of natural waters and alkali and alkaline earth salts is demonstrated. Proposed preconcentration procedure combined with ETAAS determination of trace analytes allows the determination of 0.04 g l–1 Cd, 0.1 g l–1 Cr, Cu, and Mn and 0.3 g l–1 Co, Fe, Ni and Pb in natural waters and 1.10–7% Cd, 3.10–7% Cr and Mn, 7.10–7% Co, Ni and Pb and 2.10–6% Cu and Fe in alkali and alkaline earth salts. 相似文献
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A. G. Page S. V. Godbole Madhuri J. Kulkarni S. S. Shelar B. D. Joshi 《Fresenius' Journal of Analytical Chemistry》1979,296(1):40-44
Summary An atomic absorption spectrometric method has been developed for the determination of chromium, cobalt, copper, manganese and nickel in U3O8 by electrothermal atomization of 5 mg powder samples. Nanogram amounts of all the elements can be estimated with a precision ranging between 7–12%. The non-specific absorption due to U3O8 for these measurements is negligible. The use of graphite powder with U3O8 in equal or double the sample amount improves sensitivity for the analyte element and prolongs the life of the atomizer.
Direkte AAS-Bestimmung von Co, Cr, Cu, Mn und Ni in U3O8 durch elektrothermische Atomisierung
Zusammenfassung Das entwickelte AAS-Verfahren geht von pulverförmigen 5mg-Proben aus. Nanogramm-Mengen der genannten Elemente können mit einer Genauigkeit im Bereich von 7–12% bestimmt werden. Die durch U3O8 verursachte unspezifische Absorption ist zu vernachlässigen. Durch Graphitzusatz (in der gleichen oder doppelten Menge der Probe) wird die Empfindlichkeit der Bestimmung verbessert und die Lebensdauer des Atomizers verlängert.相似文献
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A rapid radiochemical proton-activation technique based on the utilization of short-lived indicator radionuclides (t(1/2) = 7-100 min) for the determination of Cr, Ni, Cu, Zn, and Cd in niobium is described. It involves the irradiation of the samples with 13-MeV protons, the post-irradiation decontamination of the sample surface, a rapid sample dissolution, a separation procedure based on anion-exchange from HF medium, and counting the eluate with a high-resolution gamma-spectrometer. In addition, for the determination of Ni, a specific separation procedure is proposed. For a 20-min ir-radiation with a beam intensity of 10 microA and a delay time of 20 min, the limits of detection are 4 ng/g for Cr, 0.5 ng/g for Ni, 60 ng/g for Cu, 0.5 microg/g for Zn and 0.2 microg/g for Cd. For Cr, Ni, and Cu, the results obtained by this technique are compared with data obtained by radiochemical neutron-activation analysis and atomic-absorption spectrometry. 相似文献
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采用原子吸收光谱法测定了大承气颗粒剂及其原料药材中砷、铅、镉、铬和汞的含量,并参照食品中重金属的限量规定进行了比较。结果表明,大承气颗粒剂及其原料药材中的砷、铅、镉、铬和汞均低于限量标准,成品中重金属的含量均低于原料药材中的平均含量,这为大承气颗粒剂生产中的质量控制提供了依据。 相似文献
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A method for the determination of Cu, Zn, Fe, Ni and Cd by flame atomic absorption spectrophotometry (FAAS) after preconcentrating on a column containing Escherichia coli immobilized on sepiolite has been developed. Optimum pH values, amount of adsorbent, elution solution and flow rate have been obtained for the elements studied. The effect of interfering ions on the recovery of the analytes has also been investigated. Recoveries of Cu, Zn, Fe, Ni and Cd by E. coli immobilized on sepiolite were 99.1+/-0.6, 98.2+/-0.6, 98.1+/-0.5, 97.2+/-0.8 and 98.2+/-0.4% at 95% confidence level, respectively. The adsorption capacity of E. coli immobilized on sepiolite was found as 0.148, 0.064, 0.098, 0.134 and 0.088 mmol/g for Cu, Zn, Fe, Ni and Cd, respectively. The proposed method was applied to the determination of trace metals in alloys (NBS SRM 85b). Trace metals have been determined with relative error lower than 10%. 相似文献
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火焰原子吸收法连续测定茶叶中铅、铜、锌、镉含量 总被引:9,自引:2,他引:9
采用火焰原子吸收方法连续测定了茶叶中铜,铜,锌,镉的含量,方法灵敏,准确。测定时无需富集,萃取,操作简便,回收率93.0%-98.1%,相对标准偏差不超过5.3%。 相似文献
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原子吸收光谱法测定益寿回春口服液中砷铅镉铬汞的含量 总被引:6,自引:0,他引:6
卢文彪 《广东微量元素科学》2002,9(5):57-59
采用原子吸收光谱法测定了益寿回春口服液中砷、铅、镉、铬和汞的含量,并参照食品中重金属的限量规定进行了比较。结果表明,益寿回春口服液中的砷、铅、镉、铬和汞均低于限量标准,为该产品的质量控制提供了依据。 相似文献
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火焰原子吸收光谱法测定蚯蚓中铜、锌、镉和铅 总被引:1,自引:0,他引:1
随着工业生产的发展和人们生活水平的不断提高,城市垃圾处理场的重金属含量越来越高。部分重金属通过大气和水进入土壤,由于污染给生物和人类带来危害。大型土壤动物-蚯蚓,是土壤污染中敏感的指示动物,受到国内外学者的重视。因此,通过对蚯蚓的监测来评价土壤的污染程度是常用的方法之一。本法将蚯蚓洗净泥沙,置黑暗处饥饿养殖3天,待其基本排尽粪便,经烘干研磨制成粉,经硝酸-高氯酸消解后,用火焰原子吸收光谱法测定其中的铜锌镉铅含量。方法简便、快速,相对标准偏差为0.5%~3.7%,加标回收率为94.0%~106.0%,获得满意的结果。 相似文献
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采用微波消解法处理海洋贝类样品,用电感耦合等离子体质谱法测定样品中镉、铬、铜和铅等4种重金属元素的含量。选择111 Cd、53 Cr、63 Cu和208 Pb等待测元素的同位素克服了质谱干扰。4种元素分别在一定的质量浓度范围内呈线性,检出限(3s)在0.005~0.17μg.L-1之间。镉、铬、铜和铅的回收率分别为94.7%,102.1%,101.9%,105.3%;测定值的相对标准偏差(n=7)分别为4.3%,3.8%,1.5%,6.0%。 相似文献
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原子吸收光谱法测定水生生物体内铜、锌、镍、铬、铅、镉 总被引:7,自引:0,他引:7
用硝酸-高氯酸体系消解螺蛳和水葫芦样品,采用火焰原子吸收光谱法测定铜、锌、镍、铬,用石墨炉原子吸收光谱法测定铅、镉。铜、锌、镍、铬、铅、镉的检出限分别为0.328、0.126、0.271、0.416、0.006 64、0.001 15 mg/kg,线性相关系数不小于0.999 0,测定结果的相对标准偏差为1.1%~3.7%,加标回收率为86.0%~94.2%。 相似文献
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E. Ivanova I. Havezov N. Vracheva N. Jordanov 《Fresenius' Journal of Analytical Chemistry》1985,320(2):133-136
Summary A method was developed for the determination of 10 trace elements in ammonium sulphate, or sulphuric acid, respectively. The detection limits for the separate elements vary from 1×10–5 to 5×10–7%. The method includes a new approach for calibration in organic medium, consisting of conversion of the aqueous metal standards into chelate compounds in a homogeneous solution.A three-step optimization scheme for pulse aspiration of organic extracts is proposed which permits to obtain a highly reproducible and accurate signal. The solutions of the organic reagents used are subjected to a purification procedure, which lowers their impurity level for approx. one order of magnitude.
Extraktions-flammenatomabsorptiometrische Bestimmung von Mikrospuren Ag, Bi, Cd, Co, Cu, Fe, Mn, Ni, Pb und Zn in Ammoniumsulfat
Zusammenfassung Ein Verfahren wurde entwickelt zur Bestimmung dieser 10 Elemente in Ammoniumsulfat bzw. Schwefelsäure. Die Nachweisgrenzen der Elemente liegen zwischen 1 · 10–5 und 5 · 10–7%. Das Verfahren beinhaltet auch eine neue Methode zur Eichung in organischem Medium, die auf Umwandlung der wässrigen Metallstandardlösungen in Chelatverbindungen in homogener Lösung beruht. Eine dreistufige Optimierung des pulsierenden Ansaugens der organischen Extrakte wird vorgeschlagen, wodurch genaue und reproduzierbare Signale erhalten werden. Die Lösungen der organischen Reagentien werden einem Reinigungsverfahren unterzogen, das die Konzentration an Verunreinigungen um etwa eine Größenordnung senkt.相似文献
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电感耦合等离子体质谱法测定铅锌矿尾矿渣中铜、铅、锌和镉 总被引:1,自引:0,他引:1
《理化检验(化学分册)》2015,(7)
采用硝酸-氢氟酸-高氯酸溶解样品,用电感耦合等离子体质谱法测定了铅锌矿尾矿渣中的铜、铅、锌和镉。以铑为内标元素,选择63 Cu,66Zn,208 Pb,114 Cd作为测量同位素。铜、铅、锌的线性范围为200μg·L-1,镉的线性范围为1.0μg·L-1,检出限(3s)分别为0.04,0.10,0.03,0.003μg·g-1。测定值的相对标准偏差(n=11)在0.39%~2.2%之间。用此方法分析标准物质,测定值与认定值相符。 相似文献
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A novel method, combining isotope dilution with standard additions, was developed for the analysis of eight elements (Mn, Fe, Co, Ni, Cu, Zn, Cd and Pb) in seawater. The method requires just 12 mL of sample and employs an off-line pre-concentration step using the commercially available chelating resin Toyopearl AF-Chelate-650M prior to determination by high resolution inductively coupled plasma magnetic sector mass spectrometry (ICP-MS). Acidified samples were spiked with a multi-element standard of six isotopes (57Fe, 62Ni, 65Cu, 68Zn, 111Cd and 207Pb) enriched over natural abundance. In addition, standard additions of a mixed Co and Mn standard were performed on sub-sets of the same sample. All samples were irradiated using a low power (119 mW cm−2; 254 nm) UV system, to destroy organic ligands, before pre-concentration and extraction from the seawater matrix. Ammonium acetate was used to raise the pH of the 12 mL sub-samples (off-line) to pH 6.4 ± 0.2 prior to loading onto the chelating resin. The extracted metals were eluted using 1.0 M Q-HNO3 and determined using ICP-MS. The method was verified through the analysis of certified reference material (NASS-5) and the SAFe inter-comparison samples (S1 and D2), the results of which are in good agreement with the certified and reported consensus values. We also present vertical profiles of the eight metals taken from the Bermuda Atlantic Time Series (BATS) station collected during the GEOTRACES inter-comparison cruise in June 2008. 相似文献
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Determination of bioavailable fractions of Zn, Cu, Ni, Pb and Cd in soils and sludges by atomic absorption spectrometry 总被引:1,自引:0,他引:1
The single extraction procedures validated by the standards, measurement and testing programme (formerly BCR), extraction with 0.05 mol l−1 EDTA and 0.43 mol l−1 acetic acid, have been applied to reference materials of soils and sludges with certified total values of elements, in order to determine bioavailable contents of Cd, Cu, Ni, Pb and Zn. These soils, which represent uncontaminated pedologically different types of soils from Slovakia and sludges from city water treatment are characterized for the bioavailable fraction of the metals using the procedures followed by SM&T Programme. Concentrations of the elements under the study in the extracts were determined by flame (FAAS) using calibration curves in appropriate extractants and by electrothermal (ETAAS) atomic absorption spectrometry, using technique of standard additions for the evaluation of the results. The accuracy of the extraction procedures and determinations of the elements in the extracts was controlled using CRM 483 certified for EDTA- and acetic acid-extractable contents of Cd, Cu, Ni, Pb and Zn in sewage sludge amended soil. 相似文献
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微波消解-火焰原子吸收光谱法测定饲料中铁铜锰锌 总被引:6,自引:0,他引:6
铁、铜、锰和锌是饲料中重要的营养元素,其含量的测定已有标准方法,该法虽有较高的灵敏度,但分析时间冗长,试样的灰化就需16h,很难满足批量样品测定的需要。本文采用微波技术消解饲料样品,用火焰原子吸收光谱法测定铁、铜、锰和锌的含量,方法快速、灵敏、准确、操作简便。试样前处理仅需0.5h,节省了分析时间,应用于样品的分析,结果满意。 相似文献
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Combined analytical procedures consisting of wet digestion step followed by instrumental determination – differential pulse
cathodic stripping voltammetry (DPCSV) or electrothermal atomic absorption spectrometry (ETAAS) – as well as a direct analysis
method – slurry sampling ETAAS – for the determination of Cd, Co, Cr, Cu, Fe, Ni and Pb in milk, cheese and chocolate are
described and compared. Wet digestion using a mixture of HNO3-HClO4-H2O2 is proposed for complete matrix decomposition prior to trace analyte determinati on by DPCSV or ETAAS. A mixture of HNO3-H2O2 is used for slurry preparation. Optimal instrumental parameters for trace analyte measurements are presented.
The reliability of the procedures has been verified by analyzing standard reference materials. Results obtained are in good
agreement with the certified values and the relative standard deviations (for these results) are in the range 5–10% for wet
digestion DPCSV or ETAAS and 3–9% for slurry sampling ETAAS in the range of 2 μgċg−1 (Cd) to 12 μgċg−1 (Fe).
Received August 24, 1999. Revision January 20, 2000. 相似文献
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Sodium diethyldithiocarbamate in the presence of a weak oxidizing agent is used as a co-precipitative agent for the pre-concentration of Se, Cu, Pb, Zn, Fe, Co, Ni, Mn, Cr and Cd. A procedure was developed for ICP-AES determination of these elements after pre-concentration in river and waste water (an enrichment factor of 40). The recovery of all the elements tested for was more than 98%. The limits of determination (mg l−1) (10 S.D. blank) are 0.001 (Cu, Co, Cr, Mn), 0.0007 (Zn, Cd), 0.003 (Se), 0.004 (Fe), 0.007 (Ni), and 0.01 (Pb). 相似文献