Absorption flame atomic

Flame AA is the oldest of the three techniques and has been widely used for many years. The instruments are relatively inexpensive and methods have been well tested and are well understood. 

In flame AAS the sample solutions are usually nebulized pneumatically into a spray chamber and the aerosol produced is lead together with a mixture of a burning gas and an oxidant into a suitable burner. 

As the isotope shifts are often larger than the Doppler broadening, signals of different isotopes such as U and can often be differentiated, making isotopic analyses of enriched uranium possible [299]. Doppler-free spectroscopy with two laser beams in co- or counter-propagating directions can also be applied, which becomes even more isotopically selective, as isotope patterns hidden in the Doppler profile can then be visualized. 

Instrumentation for diode laser based AAS has been made commercially available and the method could expand as diode lasers penetrating further into the UV range become available, especially because of their analytical figures of merit that have been discussed and also because of their price. In diode laser AAS, the use of monochromators for spectral isolation of the analyte lines becomes completely superfluous and correction for non-element specific absorption no longer requires techniques such as Zeeman-effect background correction atomic absorption or the use of broad-band sources such as deuterium lamps. 

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With the exception of alkalis, the sensitivity is generally higher than that of atomic absorption (at least flame atomic absorption). Refer to Table 2.4. 

FLAME ATOMIC EMISSION, FLAME ATOMIC ABSORPTION,... 

Element Wavelength, nm Flame emission Flame atomic absorption Electrothermal atomic absorption Argon ICP Plasma atomic fluorescence... 

The section on Spectroscopy has been retained but with some revisions and expansion. The section includes ultraviolet-visible spectroscopy, fluorescence, infrared and Raman spectroscopy, and X-ray spectrometry. Detection limits are listed for the elements when using flame emission, flame atomic absorption, electrothermal atomic absorption, argon induction coupled plasma, and flame atomic fluorescence. Nuclear magnetic resonance embraces tables for the nuclear properties of the elements, proton chemical shifts and coupling constants, and similar material for carbon-13, boron-11, nitrogen-15, fluorine-19, silicon-19, and phosphoms-31. 

Absorbance profile for Ag and Cr in flame atomic absorption spectroscopy. 

Hobbins reported the following calibration data for the flame atomic absorption analysis for phosphorus. ... 

Small concentrations of iron can also be deterrnined by flame atomic absorption and inductively coupled plasma emission spectroscopies (see... 

The capacity factors of SN-SiO, for metal ions were determined under a range of different conditions of pH, metal ions concentrations and time of interaction. Preconcentration of Cd ", Pb ", Zn " and CvS were used for their preliminary determination by flame atomic absorption spectroscopy. The optimum pH values for quantitative soi ption ai e 5.8, 6.2, 6.5, 7.0 for Pb, Cu, Cd and Zn, respectively. The sorption ability of SN-SiO, to metal ions decrease in line Pb>Cu> >Zn>Cd. The soi ption capacity of the sorbent is 2.7,7.19,11.12,28.49 mg-g Hor Cd, Zn, Pb, andCu, respectively. The sorbent distribution coefficient calculated from soi ption isotherms was 10 ml-g for studied cations. All these metal ions can be desorbed with 5 ml of O.lmole-k HCl (sorbent recovery average out 96-100%). 

The possibility of preconcentration of selenium (IV) by coprecipitation with iron (III) hydroxide and lanthanum (III) hydroxide with subsequent determination by flame atomic absorption spectroscopy has been investigated also. The effect of nature and concentration of collector and interfering ions on precision accuracy and reproducibility of analytical signal A has been studied. Application of FefOH) as copreconcentrant leads to small relative error (less than 5%). S, is 0.1-0.2 for 5-100 p.g Se in the sample. Concentration factor is 6. The effect of concentration of hydrochloric acid on precision and accuracy of AAS determination of Se has been studied. The best results were obtained with HCl (1 1). 

Cobalt and cobalt compounds in air Lab method using flame atomic absorption spectrometry 30/2... 

At present, however, the usual flame emission method is obtained by simply operating a flame atomic absorption spectrometer in the emission mode (see Fig. 21.3). 

Koscielniak, R, Non-linear Robust Regression Procedure for Calibration in Flame Atomic Absorption Spectrometry, Analytica Chimica Acta 278, 1993, 177-187. 

Cruz, R. B. and Loon, J. C. van "A Critical Study of the Application of Graphite-Furnace Non-Flame Atomic Absorption Spectrometry to the Determination of Trace Base Metals In Complex Heavy-Matrix Sample Solutions". Anal. Chlm. Acta (1974), 72, 231-243. 

Variation In Lead Concentration Along Single Hairs as Measured by Non-Flame Atomic Absorption Spectrophotometry". Nature (1972), 238, 162-163. 

Flame atomic absorption spectrometry Flame emission spectrometry... 

Particulate lead and lead Flame atomic absorption... 

Reference methods are generally arrived at by consensus and fairly extensive testing by a number of laboratories. For example, the flame atomic absorption method for Ca in serum developed under the leadership of the agency fondly remembered as NBS, now NIST (Cali et al. 1972), was established after several inter-laboratory comparison exercises. The results were evaluated after each exercise and the procedure was changed as necessary. After five exercises, it was felt that the state-of-the-art had been reached, with the reference method being capable of measuring Ca in serum with an accuracy of 2% of the true value determined by IDMS (note that attainment of high accuracy and precision is not only a matter of the method, but is a function of both the method and analyst expertise). 

Calcium exists in the human body as Ca(II) protein-bound and free Ca (II) ions (Dilana et al. 1994). For total extracellular Ca in plasma, serum and urine a definitive isotope dilution-mass spectrometry (ID-MS) method exist. Free Ca(II) in plasma/serum can be determined with PISE, but no definitive and reference methods exist. For Ca in faeces, tissue and blood flame atomic absorption (FAAS) is used widely. 

Zhang D-Q, Li C-U, Yang L-L, Sun H-W (1998) Determination of cadmium in vegetables by derivative flame atomic absorption spectrometry with atom trapping technique. J Anal At Spectrom 13 1155-1158. 

FAAS Flame atomic absorption FTLMMS Fourier-transform laser-microprobe... 

ASTM. 1998a. ASTME1613. Standard test method for analysis of digested samples for lead by inductively coupled plasma atomic emission spectrometry (ICP-AES). Flame Atomic Absorption (FAAS), or Graphite Furnace Atomic Absorption (GFAA) Techniques. American Society for Testing and Materials. 

Eaton AD, Clesceri LS, Greenberg AE. 1995b. Method 3111, Metals by Flame Atomic Absorption Spectrometry, Standard Methods for the Examination of Water and Wastewater, American Public Health Association, Washington, DC. 

AAS is used to quantify the concentration of specific elements in solution. In flame atomic absorption, the analyte solution is introduced into the flame... 

Ho M.D., Evans G.J. Operational speciation of cadmium, copper, lead and zinc in the NIST standard reference materials 2710 and 2711 (Montana soil) by the BCR sequential extraction procedure and flame atomic absorption spectrometry. Anal Commun 1997 34 353-364. 

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. 

The concentration of copper in the column eluent was determined by flame atomic absorption spectroscopy of samples which were preconcentrated with ammonium pyrrolidine dithiocarbamate (APDC) and methyl isobutyl ketone. The pH of the acidified sample was adjusted to pH 2.5-3.5 using 400 pi 8 M ammonium acetate (Chelex cleaned). 

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