Artifact Corrections in IMPROVE
نویسندگان
چکیده
IMPROVE adjusts for positive sampling artifacts by subtracting nylon filter field blank values and quartz afterfilter values from measured ion and carbon concentrations, respectively. Artifacts have been observed to vary substantially among filter manufacturing lots, especially for nylon filters. Sulfate and nitrate artifact corrections are currently less than 10% of the measured values, but organic carbon artifacts can exceed 50% of the measured values.
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