Radon Progeny Activity Radioactive Aerosol Size Distribution Monitoring System Hardware Circuit Design

Aerosol particles in the air is mainly Radon daughter radioactive aerosol,and itsconcentration and particle size distribution are closely related to the influence ofhuman health and the environment.After radioactive nuclide and their daughtersaerosol particles are inhaled by people,which it will be deposited in different parts ofthe respiratory tract, the deposition location and deposition amount related to theaerosol particle size distribution, due to the different organization has the differentradiation sensitivity, and it contributed different doses. The related report showsthat Rn, Th and the dose contribution of daughter close to50%of the total naturaldose radiation,and radon daughters aerosol particle size is range from0.005μm to0.17μm, the dose of lung will be corresponding change from+100%to-20%.Measuring the radon daughter radioactive aerosol particle size distribution hasa very important practical significance, firstly,the thesis briefly introduces the relatedmethod, which is based on metal wire diffusion group, designed the radon daughterradioactive aerosol particle size distribution measurement circuit system, it containsCharge-sensitive preamplifier circuit and Main amplifier circuit、 Single-chipmicrocomputer control circuit、Serial communication circuit、LCD interface circuitand so on． And optimizing the measurement circuit system’s design andperformance test, and improve the system stability and reliability,the key point is thetesting capacity of Charge-sensitive preamplifier circuit,mainly the result is good.Use control circuit for measuring system and counting instrument to count to241Am and Radon daughter，then conparative the results and analysis error.Theresults shows that Radon daughter radioactive aerosol particle size distributionmeasurement circuit system’s performance is stable,and the measurement of data isaccurate and reliable.The designed of Radon daughter radioactive aerosol particle size distributionmeasurement circuit system’s performance is stable,and the measurement of data isaccurate and reliable.Due to the sampling didn’t realize miniaturization,the metalwire diffusion group fails to realize optimization design and fluid mechanics of gaspath analysis, the author only from the control of angle measurement circuit to accomplish this task, that is the thesis’s defect, this is the research focus in thefuture.