The five parts that make up the atomic absorption spectrum
The five parts that make up the atomic absorption spectrum First, the light source The function of the light source is to emit characteristic resonant radiation of the element under test. The basic requirement for the light source is that the half width of the radiated resonance radiation is significantly smaller than the half width of the absorption line; the radiation intensity is large; the background is low, less than 1% of the characteristic resonance radiation intensity; the stability is good, and the drift within 30 minutes does not exceed 1%; noise is less than 0.1%; service life is longer than 5A·h. A sharp line source such as a hollow cathode lamp is used. Second, the atomizer The function of the atomizer is to provide energy to dry, evaporate and atomize the sample. In atomic absorption spectroscopy, the atomization of the measured elements in the sample is a key part of the entire analytical process. There are two most common methods for achieving atomization: one is the flame atomization method (flame atomizer), which is the earliest atomization method used in atomic spectroscopy, and is still widely used today; the other is non- The flame atomization method, the most widely used is the graphite furnace electrothermal atomization method. Third, the splitter The beam splitter consists of an entrance and exit slit, a mirror and a dispersive element that separates the desired resonant absorption line. The key components of the beam splitter are dispersive components, and commercial instruments use gratings. The atomic absorption spectrometer does not require high resolution of the spectroscope. It has been able to distinguish the nickel three-wire Ni230.003, Ni231.603, Ni231.096nm as the standard, and then use Mn279.5 and Mn279.8nm instead of the Ni three-wire to verify the resolution. . The grating is placed behind the atomizer to prevent all unwanted radiation from the atomizer from entering the detector. Fourth, the detection system The detectors widely used in atomic absorption spectrometers are photomultiplier tubes, and some instruments also use CCDs as detectors. Guangzhou Zhongzhinan Supply Chain Co.,Ltd. , https://www.zhongzhinanlighting.com