Source Nemst filament

Evacuation is not necessary in this region and sources are much less of a problem than they are in the far-infrared. A heated black body emits strongly in the near- and mid-infrared and a Nemst filament, consisting of a mixture of rare earth oxides, or a silicon carbide Globar, emulate a black body quite well. 

A detector must have adequate sensitivity to the radiation arriving from the sample and monochromator over the entire spectral region required. In addition, the source must be sufficiently intense over the wavenumber range and transmittance range. Sources of infrared emission have included the Globar, which is constructed of silicon carbide. There is also the Nemst filament, which is a mixture of the oxides of zirconium, yttrium and erbium. A Nemst filament only conducts electricity at elevated temperatures. Most detectors have consisted of thermocouples of varying characteristics. 

The SOFC was derived from the Nemst glower, originally intended as a commercial light source to replace caibon filament lamps at the end of the last centniy. This device made nse of the Nemst mass composed of yttria-stabilized zirconia (YSZ), a predominantly ionic... 

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