Transversal heated graphite atomizers

Nowka R, Muller H (1997) Direct analysis of solid samples by graphite furnace atomic absorption spectrometry with a transversely heated graphite atomizer and D2-background correction system (SS GF-AAS). Fresenius J Anal Chem 359 132-137. 

Using a newly developed, transversely heated graphite atomizer and D2-back-ground correction (for details see Sections 2.2 and 4.3), Cd, Pb and Cr were determined in cement and river sediment samples. Of the various calibration approaches applied the best results, also in comparison with wet chemical procedures, were achieved with calibration curves constructed by means of different BCR CRMs with different analyte concentrations and usually n = to individual intakes (Nowka and Muller 1997). 

Figure 7 Electrothermal tubes available commercially (A) transversely heated graphite atomizer (THGA), (B) longitudinally heated Massmann atomizer. From Ebdon L (1998) Introduction to Analytical Atomic Spectrometry. Reproduced by permission of John Wiley Sons Limited.

Figure 21-8 (a) Transversely heated graphite furnace maintains nearly constant temperature over its whole length, thereby reducing memory effect from previous runs. The i vov platform is uniformly heated by radiation from the outer wall, not by conduction. The platform is attached to the wall by one small connection that is hidden from view. [Courtesy Perkin-Bmer Corp., Norwalk, Cl] (to) Heating profiles comparing analyte evaporation from wall and from platform. [From W. Slavin, Atomic Absorption Spectroscopy, Anal. Chem. 1982,54,685A.]... 

E. J. Gawalko, T. W. Nowicki, J. Babb, R. Tkachuk, Comparison of closed-vessel and focused open-vessel microwave dissolution for determination of cadmium, copper, lead, and selenium in wheat, wheat products, corn bran, and rice flour by transverse-heated graphite furnace atom, Int. J. Assoc. Off. Anal. Chem., 80 (1997), 379-387. 

Herzberg, J., et al., CARS Thermometry in a Transversely Heated Graphite Tube Atomizer Used in Atomic Absorption Spectrometry, Applied Physics, 61, 201, 1995. 

FIG. 4. Schematic design of an electrothermal atomizer transversely heated graphite tube and graphite contacts (Courtesy of Perkin-Elmer). 

Kumar, S.J., Meeravah, N.N., Arunachalam, J. (1998) Determination of trace impurities in high purity gaUium by inductively coupled plasma mass spectrometry and cross vaUdation of results by transverse heated graphite furnace atomic absorption spectrometry. Analytica Chimica Acta, 371,305-316. 

M.-S. Chan and S.-D. Huang. Direct determination of cadmium and copper in seawater using a transversely heated graphite furnace atomic absorption spectrometer with Zeeman-effect background corrector. Talanta 51 373-380, 2000. 

Aluminum is the third most abundant element in the Earth s crust, and its omnipresence, e.g. in dust, results in an extremely high risk of contamination, particularly when traces of this element have to be determined. The most sensitive analytical line for aluminum is at 309.271 nm with a characteristic concentration of cq = 0.37 mg/L in a nitrous oxide / acetylene flame, which is about a factor of two better than what is obtained in LS AAS. The characteristic mass at this line, using a transversely heated graphite tube atomizer, is... 

The most sensitive analytical line for arsenic is at 193.696 nm at the beginning of vacuum-UV with a characteristic concentration of cq = 0.6mg/L in an air/acetylene flame. The characteristic mass at this line, using a transversely heated graphite tube atomizer, is mo = 50 pg. 

The most sensitive analytical line for lithium is at 670.785 nm with a characteristic concentration of Co = 0.006 mg/L in an air/acetylene flame, and a linear working range up to about Ara x = 3 mg/L. The characteristic mass at this line, using a transversely heated graphite tube atomizer, is mo = 1 pg. The lithium line at 670.785 nm is actually a doublet with a separation of about 15 pm, and it also exhibits an isotope shift of the same magnitude [150]. However line broadening in conventional atomizers is usually too pronounced, so that the individual fine structure components cannot be resolved. 

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