Flame atomic spectrometry

These are among the most harmful pollutants in sewage. Essential elements (e.g., Fe) as well as toxic metals such as Cd, Hg, and Pb are included. Main sources of heavy metals are industrial wastes, mining, fuels, coal, metal plating, etc. Metal determinations in sewage are preferably carried out by atomic spectrometry (flame and electrothermal atomization), atomic emission spectrometry, inductively coupled plasma-mass spectrometry, stripping voltammetry, spectrophotometry, and kinetic methods. Hg is advantageously determined by the cold vapor technique and As by the hydride technique. 

Numerous methods have been pubUshed for the determination of trace amounts of tellurium (33—42). Instmmental analytical methods (qv) used to determine trace amounts of tellurium include atomic absorption spectrometry, flame, graphite furnace, and hydride generation inductively coupled argon plasma optical emission spectrometry inductively coupled plasma mass spectrometry neutron activation analysis and spectrophotometry (see Mass spectrometry Spectroscopy, optical). Other instmmental methods include polarography, potentiometry, emission spectroscopy, x-ray diffraction, and x-ray fluorescence. 

Flame atomic absorption spectrometry Flame emission spectrometry... 

J. A.C. Broekaert, Analytical Atomic Spectrometry with Flames... 

Winefordner JD, Vickers TJ (1964) Calculation of limit of detectability in atomic absorption flame spectrometry. Anal Chem 36 1947... 

Winefordner JD, Parsons ML, Mansfield JM, McCarthy WJ (1967) Derivation of expressions for calculation of limiting detectable atomic concentration in atomic fluorescence flame spectrometry. Anal Chem 39 436... 

FIGURE 7.20 Examples of sample containers. Left, cuvettes used in UV-VIS spectrophotometry (pathlength is the inner diameter—approximately 1 cm) center, liquid sampling cell used in IR spectrometry (pathlength is thickness of spacer to the left of the pencil tip—approximately 0.1 mm) right, atomic absorption flame (pathlength is the width of the flame—approximately 4 in.). 

From the perspective of the atomic spectroscopist, desirable properties of plasmas include high thermal temperature and sufficient energy to excite and ionize atoms which are purposefully introduced for the purposes of analysis. In terms of atomic spectrometry, this means that we would generally wish to measure the absorption or emission of radiation in the near-ultraviolet (180-350 nm) and visible (350-770 nm) parts of the spectrum. In this sense, plasmas have been variously described as electrical flames or partially ionized gases. A working definition for atomic spectrometry could be as follows ... 

Two-Photon Ionization Spectrometry of Alkali Atoms in Flames 49... 

Broekaert, J. A. C., Analytical Atomic spectrometry with Flames and Plasmas, 2nd edn, Wiley-VCH Verlag GmbH, Weinheim (2005). 

Fluorescence excitation and emission spectra of the two sodium D lines in an air-acetylene flame, (a) In the excitation spectrum, the laser was scanned, (to) In the emission spectrum, the monochromator was scanned. The monochromator slit width was the same for both spectra. [From s. J. Weeks, H. Haraguchl, and J. D. Wlnefordner, Improvement of Detection Limits in Laser-Excited Atomic Fluorescence Flame Spectrometry," Anal. Chem. 1976t 50,360.]... 

Mansfield, J. M., J. D. Winefordner, and C. Veillon High Sensitivity Determination of Zinc, Cadmium, Mercury, Thallium, Gallium, and Indium by Atomic Fluorescence Flame Spectrometry. Anal. Chem. 37, 1049 (1965). 

In an interlab oratory study involving 160 accredited hazardous materials laboratories reported by Kimbrough and Wakakuwa [28], each laboratory performed a mineral acid digestion on five soils spiked with arsenic, cadmium, molybdenum, selenium and thallium. Analysis of extracts was carried out by atomic emission spectrometry, inductively-coupled plasma mass spectrometry, flame atomic absorption spectrometry and hydride generation atomic absorption spectrometry. 

A number of techniques have been used for the speciation of arsenic compounds. The most important has been the formation of volatile hydrides of several species, separation by gas chromatography and detection by AAS. HPLC has been used to separate arsenic species. Several types of detectors have been studied for the determination of arsenic species in the column effluent. These have included AAS both off- and on-line, ICPAES and ICP-MS. An important comparative study of coupled chromatography-atomic spectrometry methods for the determination of arsenic was published (Ebdon et al., 1988). Both GC and HPLC were used as separative methods, and the detectors were FAAS, flame atomic fluorescence spectrometry (FAFS) and ICPAES. The conclusions were (1) that hydride generation and cryogenic trapping with GC-FAAS was the most... 

Matusiewicz, H. and M. Kopras. 1997. Methods for improving the sensitivity in atom trapping flame atomic absorption spectrometry Analytical scheme for the direct determination of trace elements in beer. J. Anal. At. Spectrom. 12 1287-1291. 

One of the most challenging aspects of atomic spectrometry is the incredibly wide variety of sample types that require elemental analysis. Samples cover the gamut of solids, liquids, and gases. By the nature of most modem spectrochemical methods, the latter two states are much more readily presented to sources that operate at atmospheric pressure. The most widely used of these techniques are flame and graphite furnace atomic absorption spectrophotometry (FAAS and GF-AAS) [1,2] and inductively coupled plasma atomic emission and mass spectrometries (ICP-AES and MS) [3-5]. As described in other chapters of this volume, ICP-MS is the workhorse technique for the trace element analysis of samples in the solution phase—either those that are native liquids or solids that are subjected to some sort of dissolution procedure. 

Because of the difficulty and inconvenience of sample dissolution for soil and geological samples prior to analysis by atomic spectrometry, a number of authors have investigated the possibility of direct nebulization of slurry samples into flames or plasmas.20,21 However Ebdon et al.22 reported problems... 

M. A. de la Fuente, M. Juarez, Rapid determination of calcium, magnesium, sodium and potassium in milk by flame atomic spectrometry after microwave oven digestion, Analyst, 120 (1995), 107-111. 

D. Bellido-Milla, J. M. Moreno-Perez, M. P. Hemandez-Artiga, Differentiation and classification of beers with flame atomic spectrometry and molecular absorption... 

Atomic absorption, flame emission, electrothermal atomization, inductively coupled mass spectrometry 66... 

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