SOIL AND PLANT ANALYSIS (1+1)

Accessory Sampling Techniques

Flame atomic absorption is a widely used technique that offers many advantages. However, there are analytical situations in which flame methodology is limited in sensitivity or sampling flexibility. To address such requirements, there are several accessories available that are briefly described below.

Graphite Furnace Systems
The graphite furnace, which requires only a few microliters of sample, is ideal for ultra-trace determination of more than 60 elements. It can provide detection limits 1000 times lower than those of conventional flame techniques. The energy required for atomization is supplied by applying a high electrical current through a graphite tube where the sample has been placed. The furnace is located in the sample compartment so that light from the spectral lamp passes through the graphite tube. The atomic vapor generated when the furnace is fired absorbs light from the lamp. A peak-shaped signal is produced and peak area is measured. A programmable power supply is available which provides precise control of temperature programs and storage of programs for later use.

Mercury/hydride system
The mercury/hydride system is used for the high-sensitivity determination of mercury and the metallic hydride-forming elements such as As, Se, Sb, Te, Bi, and Sn. Mercury is determined by the cold vapor technique after reduction with stannous chloride or sodium borohydride.

Flow injection systems (FIAS)
Several flow injection systems (FIAS) are available to provide a wide variety of automated sample-handling capabilities.

Flow Injection Mercury System (FIMS)
The Flow Injection Mercury System (FIMS) is a compact dedicated system for the determination of mercury.