FACTORS INFLUENCING CHARACTERISTIC MASS IN THE GRAPHITE-FURNACE

Measurements of characteristic masses for Ag, Cd, Cr, Ga, Ge, and In h ave been made over a broad temperature range. The experimental results show that the experimental values of m0 have appeared to be stable to better than 10-15% when the analytes are atomized in the temperature ranges studied. Influences of atomization temperatures on the ratio m0 (calc)/m0(exp) were studied when the analytes were evaporated from the wall, with the use of the platform and the V-shaped boat techniques. For Ag and Cd the ratio m0(calc)/m0(exp) does not change significantly , and their values appeared to be nearly 100% in the temperature range s studied when the analytes were evaporated with the use of the platfo rm and the V-shaped boat techniques. However, for the remaining four e lements (Cr, Ga, Ge, and In) the ratio m0(calc)/m0(exp) increases with the rise of atomization temperatures, and their values appear to be o nly about 20-50% in the absence of a matrix modifier. However, the rat io m0(calc)/m0(exp) is obviously increased in the presence of a matrix modifier.