different energy sourcess hollow cathode lamp

Therefore, the use of a continuum light source in AAS would obliterate the analytical specificity afforded by the technique: anything present in the sample that absorbs light in the region of overlap of (a) the emission wavelength range of the light source and (b) the wavelength range of sensitivity of the detector would be recorded in a given measurement. In AAS, any light that is passed through the sample has the potential to be absorbed by anything present in the sample.The light source- the hollow cathode lamp (HCL).

For example, the warm-up characteristics, line intensity and spectral isolation for arsenic are quite different to those for copper. Each hollow cathode lamp is different in these respects. These relate to lamp warm-up time, lamp intensity and the isolation of the preferred analytical line. AAS lamps utilize the hollow cathode effect to generate. Figure 10.46: Photo of a typical multielemental hollow cathode lamp. A number of factors affect successful lamp operation. A hollow cathode lamp is used as a spectral line source for Atomic Absorption (AA) instruments.

• While the 'fingerprint' wavelengths of each element are highly specific, they often sit at wavelengths close to those of other elements. The hollow cathode lamp is a discharge lamp designed for use as a spectral line source with atomic absorption (AA) spectrometers. The AA spectrometer hydride generator and hydride absorption cell mounted on a bracket to fit onto a burner. Because a hollow cathode lamp is a line source, P T and P 0 have different values giving a T < 100 and A > 0.

Most detectors used in AAS / OES are broad-spectrum: they report just about any light that strikes them within their respective ranges of sensitivity, which usually span several hundred nanometers.One of the strengths of atomic absorption and other ionizing elemental analysis techniques using optical detection ( ICP-OES is the main other one I know of) is that the optical absorption and emission properties at particular wavelengths are highly element-specific.ĭespite this, the reasons for desiring monochromatic, element-specific AAS light sources are as follows:

Different energy sourcess hollow cathode lamp