ATOMIC SPECTROMETRY 1. Flames 2. Electrothermal Atomizers 3. Plasmas
The graphite furnace: a resistively heated carbon tube
Sample Introduction
L’vov Platform: Maintains even temperature across sample area
Graphite Cup Atomizer
Graphite Furnace Mount
Graphite Furnace Gas Flow
Atomization Cycle: Programmed Temperatures
Standard and Sample Signals
Background Correction in Atomic Absorption Spectrometry 1.Double Beam Paths 2.Continuum Source 3.Zeeman Splitting 4.Nearby Wavelengths (Near-lines) 5.Source Broadening
Dual Beam Paths (usually not feasible)
Continuum Source Background Correction
(line source passes through furnace) Analyte Absorbance + Background Absorbance
Continuum Source Background Correction (continuum source passes through furnace) Background Only
Zeeman Background Correction
Permanent Magnet on Atomizer Source Profile (not split) Absorber Profile (always split) Polarizer passes parallel polarized light Polarizer passes perpendicularly polarized light
Zeeman Background Correction Permanent Magnet on Atomizer – Rotating Polarizer Source Profile (not split) Absorber Profile (always split) Polarizer passes parallel polarized light Absorbance + Background Polarizer passes perpendicularly polarized light Background Only
Zeeman Background Correction Modulating Magnet on Atomizer – Fixed Polarizer Source Profile (not split) Absorber Profile (magnet on-off) Polarizer passes perpendicularly polarized light Absorbance + Background Polarizer passes perpendicularly polarized light Background Only
Zeeman Background Correction Permanent Magnet on Source – Rotating Polarizer Source Profile (always split) Absorber Profile (not split) Polarizer passes parallel polarized light Absorbance + Background Polarizer passes perpendicularly polarized light Background Only
Nearby Wavelength Correction
Background Only Background + Analyte
High Resolution Continuum Source Spectra