AAS—See Atomic Absorption Spectrometry

Other methods reported for the determination of beryllium include UV-visible spectrophotometry [80,81,83], gas chromatography (GC) [82], flame atomic absorption spectrometry (AAS) [84-88] and graphite furnace (GF) AAS [89-96]. The ligand acetylacetone (acac) reacts with beryllium to form a beryllium-acac complex, and has been extensively used as an extracting reagent of beryllium. Indeed, the solvent extraction of beryllium as the acety-lacetonate complex in the presence of EDTA has been used as a pretreatment method prior to atomic absorption spectrometry [85-87]. Less than 1 p,g of beryllium can be separated from milligram levels of iron, aluminium, chromium, zinc, copper, manganese, silver, selenium, and uranium by this method. See also Sect. 5.74.9. 

Atomic absorption spectrometry. See AAS Atomic emission spectrometry. See AES... 

The most frequently applied analytical methods used for characterizing bulk and layered systems (wafers and layers for microelectronics see the example in the schematic on the right-hand side) are summarized in Figure 9.4. Besides mass spectrometric techniques there are a multitude of alternative powerful analytical techniques for characterizing such multi-layered systems. The analytical methods used for determining trace and ultratrace elements in, for example, high purity materials for microelectronic applications include AAS (atomic absorption spectrometry), XRF (X-ray fluorescence analysis), ICP-OES (optical emission spectroscopy with inductively coupled plasma), NAA (neutron activation analysis) and others. For the characterization of layered systems or for the determination of surface contamination, XPS (X-ray photon electron spectroscopy), SEM-EDX (secondary electron microscopy combined with energy disperse X-ray analysis) and... 

If the reference materials are pure substances and can be specified on the microscopic level, then they represent the unit amount of substance. Because there are no absolute pure substances the representation is in all cases an approximation. The degree of approximation is given by the accuracy of the contents of the main component. In case of pure elements, e.g. metals Fe, Cu, Zn the determination of the main component by coulometry is limited by an uncertainty of 0.01%. The determination of all impurities needs completeness and requires a great deal of analytical equipment. However, a combination of inductively coupled plasma-mass spectrometry (ICP-MS), atomic absorption spectrometry (AAS) and isotope dilution mass spectrometry (ID-MS) covering all elements of the periodic table allows a decrease of total uncertainty to 0.0032% (Cu, see Fig. 8). 

The most generally applied method for determination of an arsenical is by atomic absorption spectrometry (AAS) after reduction of the compound to AsH3. However, this only provides an indication of the presence of the element as against a natural background. Lewisite rapidly hydrolyzes to 2-chlorovinylarsonous acid (CVAA see Figure 7) in an aqueous environment such as blood plasma, and analytical methods have focused mainly on the determination of CVAA (see Chapter 16). 

Representative samples were taken during the bottling procedure to determine a number of trace elements (As, Cd, Cu, Hg, Mn, Pb, Sn, Tl, Zn) in Antarctic coastal marine sediment by Solid Sampling Zeeman Electrothermal Atomization Atomic Absorption Spectrometry (SSZ-ETA-AAS) (see Table 11.3). This technique is particularly suited to homogeneity control because of the usually low sample mass (0.1-10 mg) and the high number of parallel measurements (10-100). Additionally, all measurements are performed without any chemical sample... 

Many of the analytical methods for detecting vanadium in biological samples have also been used to measure vanadium in environmental samples. They are detailed in Table 6-2. These include GFAAS, spectrophotometry, IDMS, and ICP-AES. Other techniques employed for measuring vanadium in environmental samples are flame atomic absorption spectrometry (FAAS) and direct current plasma- atomic emission spectrometry (DCP-AES). The most widely used methods utilize some modification of atomic absorption spectrometry (AAS). In general, similar methods are employed for preparation and clean up of environmental and biological samples prior to quantification of vanadium (see Section 6.1). 

Methods for quantitative analysis of Co indude flame and graphite-furnace atomic absorption spectrometry (AAS e.g., Welz and Sperling 1999), inductively coupled plasma emission spectrometry (ICP-AES e.g., Schramel 1994), neutron activation analysis (NAA e.g., Versieck etal. 1978), ion chromatography (e.g., Haerdi 1989), and electrochemical methods such as adsorption differential pulse voltammetry (ADPV e.g., Ostapczuk etal. 1983, Wang 1994). Older photometric methods are described in the literature (e.g.. Burger 1973). For a comparative study of the most commonly employed methods in the analysis of biological materials, see Miller-Ihli and Wolf (1986) and Angerer and Schaller... 

EAAS electrothermal atomic absorption spectrometry see ET-AAS EAFS electrothermal atomic fluorescence spectrometry... 

SSETAAS solid sampling electrothermal atomic absorption spectrometry SS-GF-AAS solid sampling graphite furnace atomic absorption spectrometry (see SSETAAS)... 

Atomic absorption spectrometry (AAS) is one of the most commonly used instrumental techniques of analysis for the quantitative determination of metals and metalloids particularly in water samples, including those from wastewater, refuse seepage water, sludges and wastes. (See preceding... 

Atomic Absorption Spectrometry. Today the most common method for the determination of total mercury in body fluids or tissues is atomic absorption spectrometry with the so-called cold vapor method (CV-AAS). Especially in combination with an amalgamation device (gold/platinum gauze), this method allows a direct determination of total mercury in blood or urine without any troublesome sample preparation prior to the analyses and in a concentration range relevant not only to occupational exposure but also to that required for general population studies [100]. For the general principles of this method, see Chapter 6 of this handbook. 

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