Evaluation of Effects of NO, CO2,and Sampling Flow Rate on Arsenite Procedure for Measurement of NO2in Ambient Air.

摘要

The arsenite method for measurement of NO2in ambient air was investigated to quantify the effect of sampling flow rate and NO and CO2concentration on method response. NO and CO2were previously identified as positive and negative interferents in the method. Flow rates of 220to 270cc/min had no effect on the method response;higher flow rates decreased the method response. Atmospheres containing NO2, CO2,and NO were sampled with the arsenite method in a 3x3x3factorial experiment with five observations per cell. The concentrations were NO2--50, 150,and 250micrograms/cu m;NO--50, 180,and 310micrograms/cu m; CO2--200, 350,and 500ppm.