A method for the formation of pyrolytic graphite coatings and enhancement by calcium addition techniques for graphite rod flameless atomic absorption s

Mechanisms controlling graphite furnace atomization and stabilization of beryllium

“…(BeO)n(g) + n/2(CN)2(g) = nBeCN(g) + n/202 (9) Any cyanogen reaction with Be(g) is evidently of relatively little consequence since the cyanide profile shows no similarity to that of the Be(g). Surprisingly, the beryllium cyanamide (BeNCN) in Figure 2 does not appear to be formed from a homogeneous reaction among the reactants of reaction 8.…”

Evaluation of pyrolytic-graphite-coated tubes for graphite furnace atomic absorption spectrometry

“…As a result of these factors, an improvement in sensitivity, detection limit, and precision in graphite furnace atomic absorption may be expected when pyrolytic graphite is substituted for conventional graphite. Atomizers made of standard graphite and coated with a layer of pyrolytic graphite can also be expected to provide such improvements (1)(2)(3). Despite the number of advantages offered by pyrolytic graphite, many instrument manufacturers have failed to make use of this material for the construction of atomizers.…”

Graphite furnace atomic absorption spectrometry with graphite cloth ribbon for selenium determination

“…When a NPG tube was used in place of the PG tube where the ribbon is placed, nearly the same absorbance was obtained; therefore the effect of the ribbon is independent of the quality of the furnace tube. The Effect of charring temperature on the absorbance of selenium in the hydrochloric acid medium: with the graphite cloth ribbon and G-PG, (1) with nickel (10 gg/mL), (2) without nickel; without the ribbon, (3) a PE-NPG tube, (4) a platform-PG tube, (5) a G-PG tube. TIME/second Figure 5.…”

“…To overcome these problems many improvements in furnace design and performance have been developed: The graphite furnace was coated with a layer of pyrolytic graphite (1)(2)(3) or metals (4)(5)(6) or fitted out with a graphite platform (7)(8)(9) and tantalum or tungsten liner, collar, and wire (10)(11)(12)(13)(14).…”