Determination of metal content

ICP - MS Determination of metal content and isotope dilution analysis 147)... 

Pohl, P. (2009). Determination of metal content in honey by atomic absorption and emission spectrometries. TrAC, Trends Anal. Chem. 28,117-128. 

Requirements for the Determination of Metal Content in Virgin and Crude Oils... 

AA, and IR spectroscopy. Metal analysis may be performed by atomic absorption or emission spectroscopy and their stoichiometric amounts in the carbonyl complexes may be determined. Samples may be digested carefully and cautiously with nitric acid in a fume hood before the determination of metal contents. For mass spectrometric determination the carbonyl complex should be dissolved in an organic solvent, injected onto a GC column and identified from the characteristic mass ions. The carbonyl ligands in the complex may be determined by thermal decomposition of the metal carbonyl followed by analysis of carbon monoxide on a GC-TCD. 

The determination of metal content in products of the vegetable oil industry is supported by foreign as well as domestic prescriptions. 

A majority of soil extractions of inorganic constituents are carried out to determine the metal content of a soil sample. In these cases, it is common to use add extracting solutions. Dilute hydrochloric and sulfuric acids are most commonly used. Nitric acid is an oxidizer, so undesired oxidation can occur during the extraction process using this reagent. Phosphate is a natural... 

Two different objectives are common when extracting soil to determine its metal content. The first is to determine the amount of biologically active metal present. This is typically the goal for determining the levels of plant-required metals. In terms of total samples analyzed, this is the most common reason for extracting soil. Metals in soil that are essential to plants and that are most... 

Ure, A.M., Quevauviller, Ph., Muntau, H. and Griepink, B. (1993b) Improvements in the determination of extractable contents of trace metals in soil and sediment prior to certification (EUR Report 14763 EN). Commission of the European Communities, Luxembourg. 

Hernandez, C., Bermond, A. and Ducauze, C.J. (1994) Using chemometric data to discriminate cocoa masses analysis of metal contents applied to the determination of their geographical origin and process effect. Analusis, 22, 15-22. 

The choice of analytical procedure for the determination of metals in water using AAS is dictated by two important factors, (a) The suspended solids and organic content of the water determines whether a pretreatment is necessary, (b) The particular metal and its level of concentration in the sample decides whether a pre-concentration technique is required. In addition, this factor may be useful in choosing between employing a flame or flameless mode of analysis. 

International Organization for Standardization ISO 11212-4, Starch and Derived Products -Fleavy Metals Content - Part 4 Determination of Cadmium Content by Atomic Absorption Spectrometry with Electrothermal Atomization (1997)... 

Analysis. Multi-element calibration standards of 0.0, 5.0 and 10.0 ppm Fe, Ca, B, Cu and A1 are prepared by dissolving 0.5 and 1.0 ml of 1000 ppm multi-element standard control stock in tetralin solvent to 100 ml with the same concentration yttrium internal standard as for samples A and B. Both samples are stirred and nebulised to determine the metal content against a standard calibration curve and corrected with an internal standard using ICP-OES. 

Gee, R. and Fray, D.J. (1978) Instantaneous determination of hydrogen content in molten aluminum and its alloys. Metall. Trans. B, 9, 427-30. 

Many metal pollutants (e.g. mercury, cadmium, lead, nickel and zinc) are hazardous to human health and terrestrial ecosystems. The determination of metals in contaminated soils may be carried out for a variety of reasons, such as measurement of total or defined extractable content, which provides knowledge of soil components in respect of changes in soil composition produced by natural or anthropogenic contamination. In addition, the analysis may be designed to investigate and categorise degrees of contamination of land for current or intended use. An environmental survey of a polluted site may be undertaken to obtain information about the nature, quantity, distribution and behaviour of contaminants and, if necessary, to select the most appropriate use of the site (Hester Harrison 2001 Kibblewhite 2001). 

Solvent extraction is widely used for the isolation of single chemical species prior to a determination and the most important application of the technique is in the determination of metals present as minor and trace constituents in a variety of inorganic and organic materials. Thus the analysis of metallurgical and geological samples as well as petroleum products, foodstuffs, plant and animal tissue, and body fluids, in regard to their respective content of metals is carried out by selective solvent extraction and spectrometric determination of the metals as coloured complexes. 

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