Study on Preparation Method of High Emissivity Carbon-14 Beta Source

With more and more attention being paid to air pollution, it is particularly important to monitor PM 2.5 particles in air pollutants. As an effective means of PM 2.5 particle monitoring, the carbon-14 β source is commonly used in a beta-ray particle automatic monitor. In this paper, the optimum preparation method of high emissivity carbon-14 beta source was studied mainly from raw material mixing, filtration adsorption and source sheet sealing processes. After the mixture of barium carbonate, zirconium dioxide and acetone was magnetically stirred, filtered and adsorbed, molded and installed in source shell, the results showed that the surface emissivity of the beta particles prepared in carbon-14 beta source by this method was up to 10⁶ s^-1, At the same time, it was found that the barrier rate of the sealing film to beta particles was about 17%. Finally, we conducted quality inspection on the finished product source, and the inspection results showed that the carbon-14 source had the advantages of good sealing and no leakage, and the surface pollution-free level was far lower than the national standards.