Cold vapour atomic absorption spectrometry

Mercury vapour in air Diffusive samplers with qualitative onsite colorimetric analysis and quantitative cold vapour atomic absorption spectrometry in the laboratory 59... 

The following analytical techniques seem to be adequate for the concentrations under consideration copper and nickel by Freon extraction and FAA cold vapour atomic absorption spectrometry, cobalt by Chelex extraction and differential pulse polarography, mercury by cold vapour atomic absorption absorptiometry, lead by isotope dilution plus clean room manipulation and mass spectrometry. These techniques may be used to detect changes in the above elements for storage tests Cu at 8 nmol/kg, Ni at 5 nmol/kg, Co at 0.5 nmol/kg, Hg at 0.1 nmol/kg, and Pb at 0.7 nmol/kg. 

Methylmercury has been preconcentrated from seawater by extraction with a solution of dithizone prior to analysis by gold foil cold vapour atomic absorption spectrometry [126]. 

Langmyhr et al. [45] have applied cold vapour atomic absorption spectrometry to the determination of organomercury compounds in soils and sediments. 

Methods based on acid digestions of the soil with 7 M nitric acid [ 136] or sulfuric acid-nitric acid [137] have been described. Released mercury is absorbed in stannous chloride-sulfuric acid-hydroxylamine [ 136] or potassium permanganate-potassium persulfate-hydroxylamine-sodium chloride [137] prior to cold vapour atomic absorption spectrometry. 

Kuwae et al. [138] have described a rapid determination of mercury in soils by high-frequency induction heating (rf) followed by cold vapour atomic absorption spectrometry. The mercury released from the sample is absorbed in stannous chloride-hydroxylamine prior to atomic absorption spectrometry. Recovery of 99.4 to 99.8% mercury was obtained by this method from portions of sample containing between 0.025-0.15 p,g of mercury. 

Cold vapour atomic absorption spectrometry and atomic fluorescence spectrometry (253 nm emission) have been applied to the determination of down to 0.01 mg/kg of mercury in soils and sediments [ 144],... 

Sakamoto et al. [148] have shown that the differential determinations of different forms of mercury in soil can be accomplished by successive extraction and cold vapour atomic absorption spectrometry. 

Bandyopadhyay and Das [151] extracted mercury from soils with the liquid anion exchanger Aliquat-336 prior to determination by cold vapour atomic absorption spectrometry. 

Figure 6.1 Bar-graph of MeHg in CRM 580. The results correspond to six replicate determinations as performed by different laboratories using various methods. MEANS indicates the mean of laboratory means with 95% confidence interval. Abbreviations-. CVAAS, cold vapour atomic absorption spectrometry CVAFS, cold vapour atomic fluorescence spectrometry ECD, electron capture detection GC, gas chromatography HPLC, high-performance liquid chromatography ICPMS, inductively coupled plasma mass spectrometry MIP, microwave induced plasma atomic emission spectrometry QFAAS, quartz furnace atomic absorption spectrometry SFE, supercritical fluid extraction.

Tsalev, D.L., M. Sperling, and B. Welz. 1992,On-line microwave sample pre-treatment for hydride generation and cold vapour atomic absorption spectrometry. Part 2. Chemistry and applications. Analyst 117 1735-1741. 

Welz, B., D.L. Tsalev, and M. Sperling. 1992. On-line microwave sample pretreatment for the determination of mercury in water and urine by flow-injection cold-vapour atomic absorption spectrometry. Anal. Chim. Acta 261 91-103. 

On-line preconcentration followed by liquid chromatographic separation and cold vapour atomic absorption spectrometry have been used to detect 0.5ppt methylmercuiy in non saline water [43],... 

Maintaining the quality of food is a far more complex problem than the quality assurance of non-food products. Analytical methods are an indispensable monitoring tool for controlling levels of substances essential for health and also of toxic substances, including heavy metals. The usual techniques for detecting elements in food are flame atomic absorption spectroscopy (FAAS), graphite furnace atomic absorption spectrometry (GF AAS), hydride generation atomic absorption spectrometry (HG AAS), cold vapour atomic absorption spectrometry (CV AAS), inductively coupled plasma atomic emission spectrometry (ICP AES), inductively coupled plasma mass spectrometry (ICP MS) and neutron activation analysis (NAA). 

Cold Vapour Atomic Absorption Spectrometry CV AAS is the best and most sensitive method for determining very low levels of mercury it makes use of the fact that atoms of this element can exist in gaseous form at room temperature. 

Ahmed, R., Stoeppler, M. Decomposition and stability studies of methylmercury in water using cold vapour atomic absorption spectrometry. Analyst 111, 1371-1374 (1986)... 

DETERMINATION OF MERCURY IN ENVIRONMENTAL WATER SAMPLES BY REDUCnON-AERATION/AMALGAMATION AND COLD VAPOUR ATOMIC ABSORPTION SPECTROMETRY (CVAAS)... 

A modified reduction-aeration method to analyse mercury in environmental water samples is described. After aeration of the sample, the mercury is pre-concentrated on gold-coated sand which is then analysed by thermal desorption and cold vapour atomic absorption spectrometry (CVAAS). When applying reduction-cells of volumes up to 1 1, limits of detection as low as 1 ng.r are obtained. The method avoids matrix-effects caused by complexing agents such as Cl and 1, which interfere in the direct measurement of mercury by common CVAAS-techniques. The method was applied to dty drinking-water. Mercury levels ranging from less than 1 ng.l" to 10 ng.T were found. 

CV-AAS, Cold Vapour Atomic Absorption Spectrometry ETA-AAS, Electrothermal Atomization Atomic Absorption Spectrometry FAAS, Flame Atomic Absorption Spectrometry FIG-AAS, Flydride Generation Atomic Absorption Spectrometry ICP-AES. Inductively Coupled Plasma Atomic Emission Spectrometry ID-MS, Isotopic Dilution Mass Spectrometry HR-ICP-MS, Magnetic Sector High Resolution Inductively Coupled Plasma Mass Spectrometry NAA, Neutron Activation Analysis Q-ICP-MS, Quadrupole Inductively Coupled Plasma Mass Spectrometry Z-ETA-AAS, Zeeman Electrothermal Atomization Atomic Absorption Spectrometry... 

Bergdahl IA, Schutz A, Hansson G-A. 1995. Automated determination of inorganic mercury in blood after sulfuric acid treatment using cold vapour atomic absorption spectrometry and an inductively heated gold trap. Analyst 120 1205-1209. 

Bimie SE. 1988. Automated continuous monitoring of inorganic and total mercury in waste water and other waters by flow-injection analysis and cold-vapour atomic-absorption spectrometry. J Auto Chem 10(3) 140-143. 

Horvat M, Lupsina V. 1991. Determination of total mercury in coal fly ash by gold amalgamation cold vapour atomic-absorption spectrometry. Anal Chim Acta 243(l) 71-79. 

Landi S, Fagioli F, Locatelli C, et al. 1990. Digestion method for the determination of mercury in vegetable matrices by cold vapour atomic-absorption spectrometry. Analyst 115(2) 173-177. 

Munaf E, Takeuchi T, Ishii D, et al. 1991. Continuous monitoring system for total mercury in waste water by cold vapour atomic-absorption spectrometry and continuous-microflow analysis. Anal Sci 7(4) 605-609. 

Haase O., Klare M., Krengel-Rothensee K. and Broekaert J. A. C. (1998) Evaluation of the determination of mercury at the trace and ultratrace levels in the presence of high concentrations of NaCl by flow injection-cold vapour atomic absorption spectrometry using SnCl2 and NaBH4, Analyst 123 1219-1222. 

As mentioned before, two interlaboratory studies were organised prior to certification, involving ca. 15 laboratories using techniques such as cold vapour atomic absorption spectrometry, direct current plasma atomic emission spectrometry (DCP-AES), differential pulse anodic stripping voltammetry (DPASV), microwave plasma atomic emission spectrometry (MIP-AES), electrothermal atomic absorption spectrometry (ETAAS) and neutron activation analysis with radiochemical separation (RNAA). 

Two techniques were selected for certification, namely cold vapour atomic absorption spectrometry (CVAAS) and cold vapour atomic emission spectrometry (CVAES) applied after a variety of sample pretreatment, e.g. oxidation with BrCl or Kmn04, reduction with SnCl2, UV-irradiation, gold preconcentration etc. 

CVAAS Cold vapour atomic absorption spectrometry... 

Hydride generation, as demonstrated by the determination of toxic arsenic species in human urine by cold-vapour atomic absorption spectrometry [148]. Two advanced oxidation processes relying on high-intensity focussed ultrasound were compared and ultrasound played an important role in both. Accurate results were reported. 

Cold vapour atomic absorption spectrometry (CV-AAS) or atomic fluorescence spectrometry (CV-AFS) for the determination of Hg. 

The most common technique for the determination of mercury in environmental samples is cold vapour atomic absorption spectrometry (CV-AAS) due to its simplicity and sensitivity. The flameless procedure was investigated by Hatch and Ott (1968) with a view to simplifying the apparatus required and improving the sensitivity of the method. The method is based on the unique properties of mercury. Elemental mercury has an appreciable vapour pressure at ambient temperature and the vapour is stable and monatomic. Mercury can easily be reduced to metal from its compounds. The mercury vapour may be introduced into a stream of an inert gas and measured by atomic absorption or atomic fluorescence of the cold vapour without the need of atomiser devices. 

ISO/DIS 16772 Soil quality - Determination of mercury in aqua regia soil extracts with cold-vapour atomic absorption spectrometry or cold-vapour atomic fluorescence spectrometry. 

Falter R and Scholer HE (1994) Interfacing high-performance liquid chromatography and cold vapour atomic absorption spectrometry with on-line UV... 

Murphy J, Jones P and Hill SJ (1996) Determination of total mercury in environmental and biological samples by flow injection cold vapour atomic absorption spectrometry. Spectrochim Acta Part B 51 1867-1873. 

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