Nonflame atomizers

Montaser, A. and Crouch, S. R. "Analytical Applications of the Graphite Braid Nonflame Atomizer". Anal. Chem. (1974),... 

Heating of Electrically Heated Nonflame Atomic Vapor Cells". Anal. Chem. (1975), 38-45. 

Sarbeck, J. R. and Landgraf, W. C. "Automated Peak Discrimination and Integration for Nonflame Atomic Absorption Analysis at Nanogram Levels". J. Pharm. Scl (1974), 63, 929-930. 

Nonflame atom reservoirs have been developed for specific atomic spectrometric techniques. Electrothermal atomizers (carbon rods, carbon furnaces, or tantalum ribbons) have been developed for AAS or AFS since they require the generation of ground state atoms, whereas... 

In general, as an analytical technique for trace metal (see Trace Element) determinations, AAS has important advantages. It has high sensitivity for many elements, with perhaps 60 or so elements measurable with flame atomization in the ppm range ( 0.1-10 J,gcm , or 10 -10" g on an absolute basis), and more than half of these measurable at significantly lower concentrations with nonflame atomization. In addition it is simple, rapid, and relatively low cost and can be highly specific, exhibiting few interferences. 

The uptake of aluminum, cadmium, chromium, cobalt, cop-per, iron, lead, magnesium, manganese, molybdenum, nickel, silver, tin, and zinc by B. subtilis Strain 168 is reported. These data were obtained during the lag phase, exponential phase, stationary phase, and the sporulation phase of the maturation cycle of this bacterial strain. Nonflame atomic absorption spectrometry was the method of analysis for all the metals except calcium, which was determined by flame atomic absorption spectrometry. The complete microbiological and analytical procedures are described. Uptake curves as a function of moles per cell, of moles per dry weight of a cell, and of percent available are reported. The data show that these metals seem to be required for growth. No attempts were made to postulate the roles played by these metals. 

Apparatus. A nonflame atomic absorption spectrometer (Varian-Techtron AA-5, Model 63 Carbon Rod Atomizer) with background correction was used for all of the analyses with the exception of calcium. Calcium was determined by flame atomic absorption spectrometry (Varian-Techtron Model 1000). 

Various measurement techniques have been used after matrix destruction. Small amounts of mercury are generally determined by conversion from an ionic species in aqueous solution to the elemental vapor, which is measured spectroscopically by atomic fluorescence, ultraviolet, or atomic absorption techniques (1,5, 6,9,10,11,12,13,14,15,16). Review articles covering the determination of small amounts of mercury in organic and inorganic samples (17) and the determination of mercury by nonflame atomic absorption and fluorescence spectroscopy (18) have recently appeared. In certain instances detection limits of 1 ng/g have been possible. 

Uee am (1975) The determination of mercury by nonflame atomic absorption and fluorescence spectrometry, A review. Anal. Chim. Acta 76 1—26. 

Lead in nitric acid digests of hair has been accurately measured by flame atomic spectrophotometry (S6). Renshaw et al. (R3) used nonflame atomic absorption to measure lead in single sections of hair. 

Monitoring items include the measurement of the 7 heavy metal indexes Cu, Pb, Zn, Cd, Cr, Hg and As. Sediments decomposition and monitoring methods can be found in Part 5 of The Specification for Marine Monitoring—Sediments Analysis (GB17378.5-2007). For Cu and Zn, the flame atomic absorption spectrophotometry is adopted for Pb, Cd and Cr, the nonflame atomic absorption spectrophotometry is used For Hg and As, the atomic fluorescence spectroscopy is applied. The accuracy of standard substances is also measured according to national offshore sediment analysis. The analysis results meet the requirement. During the analysis, reagent blank and parallel samples are casually measured, the results of which show that the analysis process is not polluted and the relative standard deviation for the parallel samples are all lower than 10%. 

In a similar way to the flame emission spectrometers described in Topic E4, a flame may be used to volatilize the sample. Nonflame atomizers, particularly the graphite furnace, are very useful especially when only small volumes of sample are available. 

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