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Used in the atomic energy industry and the defense industry: graphite has a good neutron moderator for use in atomic reactors, and a uranium-graphite reactor is a more widely used atomic reactor. The decelerating material in the nuclear reactor as a power source should have high melting point, stable and corrosion resistance, and graphite can fully meet the above requirements. The purity of graphite used as an atomic reactor is very high, and the impurity content should not exceed several tens of PPM. In particular, the boron content should be less than 0.5 PPM. In the defense industry, graphite is also used to make solid fuel rocket nozzles, missile nose cones, parts of space navigation equipment, insulation materials and radiation protection materials.

Graphite furnace atomic absorption spectrometry is a spectrometric method in which a graphite coating is used to evaporate a sample. In short, this technique is based on the fact that free atoms can absorb light of a certain frequency and wavelengths with special interest elements. Within a certain range, the absorbed light waves can be directly associated with the object to be analyzed. Free atoms of many elements can be extracted from the sample at high temperatures. In graphite furnace atomic absorption spectrometry, the sample is stored in a small graphite cube with graphite or pyrolytic carbon coating. This cube can be heated to evaporate and decompose the sample. We can calibrate the instrument to a known concentration to determine the degree of concentration through the working curve. Compared with atomic adsorption, graphite furnaces have the following advantages:

1. For many elements, the graphite furnace detection range can reach one part per billion;
2. With improved equipment, the obstruction is minimized;
3. A large amount of matrix is absorbed by atoms, and the graphite furnace can detect most known elements.