Flame atomic emission spectrometry,

The majority of commercial atomic absorption spectrometers permit both flame atomic absorption and flame atomic emission measurements to be performed. Thus, flame AES is no longer considered as an independent instrumental technique, except for the determination of sodium and potassium (as well as calcium or lithium) in biological samples by flame photometers. 

No additional light sources (hollow cathode lamps or EDLs) are required in flame AES, which can be regarded as an advantage of this technique. The most important difference between flame AAS and flame AES is spectral 

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Instrumentation. Flame Characteristics. Flame Processes. Emission Spectra. Quantitative Measurements and Interferences. Applications of Flame Photometry and Flame Atomic Emission Spectrometry. 

Applications of Flame Photometry and Flame Atomic Emission Spectrometry... 

Analytical Techniques Atomic absorption spectrometry, 158, 117 multielement atomic absorption methods of analysis, 158, 145 ion microscopy in biology and medicine, 158, 157 flame atomic emission spectrometry, 158, 180 inductively coupled plasma-emission spectrometry, 158, 190 inductively coupled plasma-mass spectrometry, 158, 205 atomic fluorescence spectrometry, 158, 222 electrochemical methods of analysis, 158, 243 neutron activation analysis, 158, 267. 

In the past, flames used for atomic absorption spectrometry have also been used for atomic emission spectrometry, and these are described in some detail in Chapter 2. However, the advent of plasma excitation sources has resulted in the demise of flame atomic emission spectrometry, for the reasons discussed in Section 4.2.3. 

A wide range of instrumentation may be employed for flame atomic emission spectrometry, from filter photometers to highly sophisticated... 

X-ray fluorence spectrometry was performed by P. A. Pella and flame atomic emission spectrometry by T. A. Butler, both of the NIST Analytical Chemistry Division. 

Flames (temperatures from 1700°C to 3100°C) and plasmas (temperatures ranging between 4000°C and 6000°C) are very efficient means of atomization they are used in FAAS, flame atomic emission spectrometry (FAES), ICP-OES, and ICP-MS. High temperatures (up to 3000°C) can also be obtained if an intense electrical current is set up between two electrical contacts. This type of atomization by electrical heating (electrothermal atomization) is the basis of ETA AS. 

For instance, those elements present at relatively high concentration levels in milk are usually determined by FAAS or flame atomic emission spectrometry (FAES). On the other hand, if better LoDs are needed (e.g., ng g-1), the technique of choice would be ET-AAS. For multielemental analysis plasma-based techniques are recommended, such as AES for major elements and trace elements, or, as described below, mass spectrometry (MS) for major, trace, and ultratrace elements. The most relevant applications of these atomic techniques for elemental analysis in milk samples are summarized in Table 13.7. 

APPLICATIONS OF FLAME PHOTOMETRY . /lND FLAME - ATOMIC EMISSION SPECTROMETRY... 

Matusiewicz, H. Acid vapour-phase pressure decomposition for the determination of elements in biological materials by flame atomic emission spectrometry. J. Anal. At. Spectrom. 4, 265-269 (1989)... 

Schiefer HP, Gramain P, Kraeminger E. 1980. Improvement of the uranium determination in flame atomic emission spectrometry by addition of cobalt nitrate an interference agent. Fresenius Z. Anal Chem 303 29. 

E532 Kulpmann, W.R. (1989). Influence of protein on the determination of sodium, potassium and chloride in serum by Ektachem DT 60 with the DTE Module Evaluation with special attention to a possible protein error by flame atomic emission spectrometry and ion-selective electrodes proposals to their calibration. J. Clin. Chem. Clin. Biochem. 27, 815-824. 

The oldest of the spectroscopic radiation sources, a flame, has a low temperature (see Section 4.3.1) but therefore good spatial and temporal stability. It easily takes up wet aerosols produced by pneumatic nebulization. Flame atomic emission spectrometry [265] is still a most sensitive technique for the determination of the alkali elements, as eg. is applied for serum analysis. With the aid of hot flames such as the nitrous oxide-acetylene flame, a number of elements can be determined, however, not down to low concentrations [349]. Moreover, interferences arising from the formation of stable compounds are high. Further spectral interferences can also occur. They are due to the emission of intense rotation-vibration band spectra, including the OH (310-330 nm), NH (around 340 nm), N2 bands (around 390 nm), C2 bands (Swan bands around 450 nm, etc.) [20], Also analyte bands may occur. The S2 bands and the CS bands around 390 nm [350] can even be used for the determination of these elements while performing element-specific detection in gas chromatography. However, SiO and other bands may hamper analyses considerably. 

M.I.G.S. Almeida, M.A. Segundo, J.L.F.C. Lima, A.O.S.S. Rangel, Interfacing multi-syringe flow injection analysis to flame atomic emission spectrometry an intelligent system for automatic sample dilution and determination of potassium, J. Anal. At. Spectrom. 24 (2009) 340. 

Instrumentation. Flame characteristics. Flame processes. Emission spectra. Quantitative measurements and interferences. Applicaiion.s of flame photometry and flame atomic emission spectrometry. 

Emission spectrometry using chemical flames (flame atomic emission spectrometry, FAES) as excitation sources is the earlier counterpart to flame atomic absorption spectrometry. In this context emission techniques involving arc/spark and direct or inductively coupled plasma for excitation are omitted and treated separately. Other terms used for this technique include optical emission, flame emission, flame photometry, atomic emission, and this technique could encompass molecular emission, graphite furnace atomic emission and molecular emission cavity analysis (MEGA). 

Regarding historical insight and descriptions of principles and fundamentals of flame atomic emission spectrometry, a chapter on flame photometry appeared in the first edition of Treatise on Analytical Chemistry (Vallee and Thiers 1965) covering the flame and burner, photometer/spec-trometer, fundamental discussion of excitation and processes within the flame, cation and anion interferences and handling of analytical samples. In an analogous, expanded, detailed and excellent treatment of EAES in the second edition of the Treatise on Analytical Chemistry, Syty (1981) discusses types of flames used for excitation, processes within flames, spectral, chemical and physical interferences and remedies. 

The basic principles behind flame atomic emission spectrometry have many facets in common with the other optical atomic spec-... 

FAES flame atomic emission spectrometry FANES furnace atomic non-thermal excitation spectrometry... 

FAAS is the oldest version of AAS. It works with liquid samples which after nebu-lization are mixed with acetylene and introduced in a flame atomizer burner with air-acetylene or N20-acetylene flame. A single measurement can be completed within 10 s. Theoretically the method is applicable to 60-70 elements and due to its low cost, selectivity and simple operation is preferred whenever the concentration of the determined elements is within its possibilities. The sensitivity of FAAS is of the same order of magnitude as of ICP-AES and for some elements even worse which in recent years has lead to the replacement of FAAS with the multielement ICP-AES. To increase the sensitivity of FAAS usually preconcentration procedures are applied before measurement. Otherwise FAAS permits direct measurements in the low mg/kg range of a number of metals in soils and sediments, six to ten elements in plants and in natural waters. It is sensitive enough for the direct determination of Al., Ba, Ca, Cu, Fe, K, Na, Mg, Mn and Zn in different environmental materials (alkaline metals are determined by flame atomic emission spectrometry). Due to the narrow dynamic range problems with the accuracy appear (e.g. Djingova et al., 1991) and very often dilutions are necessary which decreases relative sensitivity and increases the possibilities for errors. 

The human eye is a useful detector for qualitative analysis but not for quantitative analysis. Replacing the human eye with a spectrometer and photon detector such as a PMT or CCD permits more accurate identification of the elements present because the exact wavelengths emitted by the sample can be determined. In addition, the use of a photon detector permits quantitative analysis of the sample. The wavelength of the radiation indicates what element is present, and the radiation intensity indicates how much of the element is present. Flame atomic emission spectrometry is particularly useful for the determination of the elements in the first two groups of the periodic table, including sodium, potassium, lithium, calcium, magnesium, strontium, and barium. The determination of these elements is often called for in medicine, agriculture, and animal science. Remember that the term spectrometry is used for quantitative analysis by the measurement of radiation intensity. 

Tests for certain metals can be carried out conveniently on solutions using flame atomic emission spectrometry (FAES) or flame atomic absorption spectrometry (FAAS), if the appropriate apparatus is available. These tests will be described under Section 2.7. 

In flame atomic emission spectrometry (FAES) the sample solution is sprayed into a flame, and by means of a monochromator the emitted radiation is analysed. As the emission spectrum is characteristic for each element, by identifying the wavelengths of the lines in the spectrum, the presence or absence of a metal can thus be established. 

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