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Along with China's rapid economic development , the problem of air pollution is more and more attention has been paid . Atmospheric aerosol pollution would not only human health hazard , and would have a lot of both the environment and climate impact , for example, cause the light attenuation to reduce atmospheric visibility . Reflect the extinction coefficient of the atmospheric aerosol extinction characteristics , based on the coefficient of transmittance and visibility of atmospheric environmental quality issues can be further discussed , measurements of atmospheric aerosol extinction coefficient has important practical significance . The measurement system using the filter membrane aerosol particle measurement system all the way to the light beam passes through a half mirror is divided into two light . All the way to the reference beam , filtered atmospheric , another way to measure the beam directly through unfiltered atmosphere . By both road light compared to the unstable due to the light intensity , atmospheric molecules on the measurement results , thereby improving the accuracy of the system . The hardware portion of the system include a light source modulator circuit, the photoelectric detection circuit , the filter circuit and a truth value converter circuit . The software part of a modular design method , including the clock setting subroutine LCD initialization subroutine , AD collection initialization subroutine , the pulse signal generator module . Use of the MSP430 own rich resources , strong light by conditioning acquisition, processing operations , the result of the operation by the LCD display to the user . Detection system measured part of the different concentrations of aerosol , good linearity , the linearity error is less than 4% . The method is designed for detection of atmospheric aerosol extinction coefficient is small size , simple operation , fast detection monitoring atmospheric pollution and visibility value .
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