The detection methods of ammonium metatungstate are graphite furnace atomic absorption spectrometry (GFAAS), flame atomic absorption spectrometry (FAAS), inductively coupled plasma emission spectrum (ICP-MS) and coprecipitation separation - hydride atomic fluorescence spectrometry (i.e. coprecipitation separation - HG - AFS method.

 

Graphite furnace atomic absorption spectrometry (GFAAS) is the method absorbing and analyzing atoms by atomization with current heating in an atomization device which produced by graphite and to form shapes of tubes, cups and others. Since all atoms of sample are getting involved in the atomization, and the atomic concentration diluted in the flame gas has been avoided, then the analytical sensitivity has been greatly improved. While, when that method applied in detecting trace metal element, its property is better than many of other methods, and will be used in analysis of small amount samples and detect analysis of solid sample.

 

Detection equipments of ammonium metatungstate are atomization device, flame atomic absorption spectrometer, and inductively coupled plasma mass spectrometer ect..

1. Atomization device is a device for sample atomization of atomic absorption spectrometry, which is used in both graphite furnace atomic absorption spectrometry (GFAAS) and flame atomic absorption spectrometry (FAAS). It converts the sample to a free atomic vapor (ground state atom) to absorb the characteristic radiation, and to calculate the element to be measured. There are many kinds of atomizers, and they can be divided into two categories of fire stuffing atomizer and electrothermal atomizer in common. The former includes pre-mixed and full consumption type; the latter includes graphite furnace, carbon wire atomizer, carbon rod atomizer, graphite increase exhaust, and graphite probes ect.;

2. Inductively coupled plasma mass spectrometer consists of plasma torch (composed of three concentric quartz tube), high frequency generator (to produce high frequency current), induction coil, gas supply system and atomization system and other parts;

3. Flame atomic absorption spectrometer is composed of light source, atomization system, spectroscopic system and detection system. The principle is that the instrument emits light with the characteristic spectral line of the element to be measured from the light source, then when the sample vapor passes through, the light will be absorbed by the under measure ground state atom, and finally measured by the weakened degree of radiation characteristic spectrum of light.