Urbanization, Energy, and Air Pollution in China The Challenges Ahead: Proceedings of a Symposium (2004) / Chapter Skim
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Sampling and Analysis Monitoring and Assessing Particulate Matter--JUDITH C. CHOW and JOHN G. WATSON
Sampling and Analysis Monitoring and Assessing Particulate Matter--JUDITH C. CHOW and JOHN G. WATSON
Pages 125-138
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Sampling and Analysis
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is a pollutant that adversely affects health, regional haze, global climate, ecosystems, and property. Mass measurements of PM were first made in the late nineteenth century by drawing ambient air through filter paper that was weighed before and after sampling.
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Secondary nitrate is related to ozone that derives from NOx and VOC precursor gases. A large quantity of precursor gases and primary particles comes from combustion sources that also emit carbon dioxide, a greenhouse gas.
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These sites would have instrumentation similar to that of Level III and Level II sites to determine comparability, as well as detailed particle size ranges, PM chemistry, and precursor gases. They would provide an infra structure for testing and evaluating new measurement concepts and de veloping procedures to implement them at Level II and III sites.
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(1999) set up a closely spaced monitoring network with 29 Level III neighborhood-scale satellite sites surrounding two Level II urban sites with a study domain of 12 km × 13 km.
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. Selection of the appropriate sampling substrates depends on particulate sampling efficiency, mechanical stability, chemical stability, temperature stability, and cost/availability.
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Denuders and backup filters are often used to evaluate and quantify positive and negative artifacts. Denuders remove gases that might absorb onto a filter; backup filters capture gases that have evaporated from sampled particles.
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charring was found throughout the filter, either from adsorbed organic vapors during sampling or adsorbed vaporized particles during analysis or liquid organic particles; (2) elemental carbon near the filter surface evolves earlier than some of the charred organic carbon embedded in the filters during thermal analysis; and (3)
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an evaluation of the effects of nonabsorbing particles, transmittance wavelengths, initial darkness, carbonate deposits, and oxygen-supplying minerals; and (7) optimizing fractions to identify source contributions.
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1995. Measurement methods to determine compliance with ambient air quality standards for suspended particles.
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1995. Measurement methods to determine compliance with am bient air quality standards for suspended particles: 1995 critical review discussion.
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EPA-454/R-98-012. Re search Triangle Park, N.C.: Environmental Protection Agency, Office of Air Quality Planning and Standards.
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