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Carbon rod atomizer
The second category of graphite graphite furnaces is the carbon-rod atomizer. A A carbon-rod atomizer

consists of a solid cylindrical graphite cal graphite rod which has a hole for the sample cut for the sample cut into its center. The
rod is supported by metallic tesupported by metallic terminals that provide it with electric connection to the power provide it with electric connection to the power

supply. As in the tubular graphitetubular graphite furnace, the carbon rod is protected from Oxidatirom Oxidation by argon
or nitrogen that flows over it. The carbon rod can be enclosed flows over it. The carbon rod can be enclosed in metallicmetallic jacket with quartz

windows. A sketch of a carbon carbon rod atomizer is shown in Fig.

A carbon rod atomizer is a carbon-rod atomizer in which the ample hole is n which the ample hole is replaced with a

carbon sample cup. Carbon-rod rod atomizer does not appear to be as popular aspopular as tubular furnaces.

W
WAVELENGTH SELECTORSAVELENGTH SELECTORS
M
Monochromators are used universally as the onochromators are used universally as the wavelength-selection devices in ices in atomic absorption
spectrophotometers. Typicallyically the bandpass of the monochromators are 0.2, 0.5, or 1 of the monochromators are 0.2, 0.5, or 1 nm. The

width of the absorptive line in most cellsn most cells is about 0.004 nm, which is considerably narrowhich is considerably narrower than
the bandpass of the monochromator.chromator.

W
Wavelength Selection Devicesavelength Selection Devices
Filters
T
The simplest and most inexpensive way to select certain he simplest and most inexpensive way to select certain portions of the electromagnetic portions of the electromagnetic
spectrum is with a filter. There are two major types, absopectrum is with a filter. There are two major types, absorption filters and interference rption filters and interference filters.
s
Absorption filters can be as simple as a piece ofbsorption filters can be as simple as a piece of colored glass. Bluelue glass transmits blue
A
wavelengths of the visible spectrum but ths of the visible spectrum but absorbs red and yellow wavelengths. This is an example absorbs red and yellow wavelengths. This is an example

o
of an absorption filter for isolatingf an absorption filter for isolating the blue region of the visible spectrum. Colored glass the blue region of the visible spectrum. Colored glass
a
absorption filters can be purchasedbsorption filters can be purchased that isolates various ranges of visible light. These filters are tes various ranges of visible light. These filters are
stable, simple, and cheap, so they are excellent for use in portable spectrometers designed to be so they are excellent for use in portable spectrometers designed to be so they are excellent for use in portable spectrometers designed to be
carried into the field. The biggest limitation is that the range of wavelengths transmitted is broad field. The biggest limitation is that the range of wavelengths transmitted is broad field. The biggest limitation is that the range of wavelengths transmitted is broad

compared with prisms and gratings which are also devices used to select a narrow wavelength with prisms and gratings which are also devices used to select a narrow wavelength with prisms and gratings which are also devices used to select a narrow wavelength

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