Determination of gallium by graphite furnace atomic absorption spectrometry using a zirconium impregnated graphite tube

Atomization Mechanism of Gallium in Graphite Furnace Atomic Absorption Spectrometry

“…The following two-step atomization mechanism was proposed for platform atomization using a shadow spectral filming technique.9' 1° The analyte vaporizes as Ga2O(g) from the platform and transfers to the wall, and the Ga2O(g) is then reduced to monoatomic state of Ga on the hot graphite surface. Kuga reported that a clear double-peak signal for gallium appears, and that the second peak disappears when using a zirconiumimpregnated graphite tube, 11 Oxygen is chemically active and is useful as a matrix modifier that promotes ashing in graphite furnace AAS. When oxygen is added to the purge gas, hightemperature shifts in Tapp take place for elements atomized via oxide intermediates8' 12-14, in response to a change in the oxygen partial pressure in the furnace.…”

Determination of gallium in sediment, coal, coal fly ash, and botanical samples by graphite furnace atomic absorption spectrometry using nickel matrix modification

“…The concentration of gallium in silicate rocks is normally in the range of 10 to 100 µg/g (1). The methods present in use for the determination of gallium in rocks, ores, metals, and other inorganic materials have included flame atomic absorption spectrometry after solvent extraction (2) or anion exchange separation (3) and graphite furnace atomic absorption spectrometry using conventional graphite tube atomization (4), Zr-coating technique (5), metal atomizer (6), or atomization from platform (7). In general, graphite furnace atomic absorption spectrometry is sensitive enough to be applicable to a variety of samples.…”

“…In this study the NIOSH method for formaldehyde analysis has been modified to improve its sensitivity from 0.1-2 ppm to the parts-per-billion level where it can compete with GC and HPLC methods (4)(5)(6). The modifications to technique include diluting the chromotropic acid solutions 10-fold and then analyzing the samples with a laser thermal lens (LTL) spectrometer rather than a standard absorption spectrophotometer.…”