| With the rapid development of economy, the process of urbanization was accelerating, and the activity space of the people became more and more widely which gradually expended to altitude range of surface layer, so that the upper atmosphere had suffered a different degree of impact and pollution. Thus, it is increasingly significance to carry out the study on the changes of nitrogen oxides and ozone and other pollutants of surface layer, with that would not only help people have thorough understanding of the influence of nitrogen oxides and ozone to the local atmospheric environment, but also provided certain reference for the formulation of air pollution control measures.In April and May 2015, we observed nitrogen oxides and ozone and related meteorological elements in 1m to 46m height range for 24 hours'high resolution day and night experiment of development zone of Baoji. We concluded regularities of diurnal and vertical variation of nitrogen oxides and ozone. We also analyzed effects of various meteorological elements of nitrogen oxides and ozone concentration. In the last part of the paper, we made evaluation and prediction of nitrogen oxides and ozone concentration in the development zone of Baoji. The specific conclusions were as follows:(1)In April, the average concentration of nitrogen oxides was 0.266mg/m3, the range was 0.045?0.712mg/m3. The change of concentration could be divided into four periods.The first period was 8:00?12:00, the average concentration was 0.459mg/m3, and the change range was 0.187?0.712mg/m3, which was the highest period of the nitrogen oxide concentration. The second period was 14:00?16:00, the average concentration was 0.166mg/m3, and the change range was 0.045?0.314mg/m3, which was the lowest period of the nitrogen oxide concentration. The third period was 20:00-0:00, the average concentration was 0.259mg/m3, and the change range was 0.147?0.353mg/m3, which was the sub high period of the nitrogen oxide concentration. The fourth period was 2:00-6:00 period, the average concentration was 0.178mg/m3, and the change range was 0.090?0.277mg/m3, which was the sub low period of the nitrogen oxide concentration.In May, the average concentration of nitrogen oxides was 0.360mg/m3, the range was 0.077?0.801mg/m3. The change of concentration could be divided into three periods. The first period was 8:00?12:00, which was the highest period of the nitrogen oxide concentration, the average concentration was 0.612mg/m3, and the range was 0.374?0.801mg/m3, which was the highest period of the nitrogen oxide concentration. The second period was 14:00?18:00, the average concentration was 0.195mg/m3, and the range was 0.077?0.278mg/m3, which was the lowest period of the nitrogen oxide concentration. The third period was 20:00?6:00, the average concentration was 0.317mg/m3, and the change range was 0.240?0.411mg/m3, which was the middle period of the nitrogen oxide concentration.(2)In April, the average concentration of ozone was 0.042mg/m3, and the range was 0.021-0.068mg/m3. The change of concentration could be divided into three periods. The first period was 8:00?10:00, the average concentration was 0.041mg/m3, and the range was 0.021?0.059mg/m, which was the middle period of the ozone concentration. The second period was 12:00?18:00, the average concentration was 0.050mg/m3, and the range was 0.035-0.068mg/m3, which was the highest period of the ozone concentration. The third period was 20:00?6:00, the average concentration was 0.038mg/m3, and the range was 0.022?0.051mg/m3, which was the middle period of the lowest concentration.In May, the average concentration of ozone was 0.040mg/m3, and the range was 0.021?0.070mg/m3. The change of concentration could be divided into three periods. The first period was 8:00?10:00, the average concentration was 0.039mg/m3, and the range was 0.024?0.070mg/m3, which was the middle period of the ozone concentration. The second period was 12:00?20:00, the average concentration was 0.045mg/m3, and the range was 0.029?0.070mg/m3, which was the highest period of the ozone concentration. The third period was 22:00-6:00, the average concentration was 0.035mg/m3, and the range was 0.021-0.052mg/m3, which was the lowest period of the ozone concentration.(3)In April, nitrogen oxides concentration in the vertical direction could be divided into two heights, the dividing point was 22m.From lm to 22m, the average concentration was 0.222mg/m3, variation range was 0.685mg/m3, and the average increasing rate was 4.70×10-3mg/m3, which was the higher period of the average increasing rate. From 25m to 46m, the average concentration was 0.373mg/m3, variation range was 0.707mg/m3, and the average increasing rate was 0.57×10-3mg/m3, which was the lower period of the average increasing rate.In May, nitrogen oxides concentration in the vertical direction could be divided into two heights, the dividing point was 22m.From lm to 22m, the average concentration was 0.347mg/m3, variation range was 0.685mg/m3, and the average increasing rate was 4.70×10-3mg/m3, which was the higher period of the average increasing rate. From 25m to 46m, the average concentration was 0.373mg/m3, variation range was 0.707mg/m3, and the average increasing rate was 0.57×10-3mg/m3, which was the lower period of the average increasing rate.(4)In April, ozone concentration in the vertical direction could be divided into two heights, the dividing point was 22m. From lm to 22m, the average concentration was 0.036mg/m3, variation range was 0.034mg/m3, and the average increasing rate was 1.93×10-3mg/m3, which was the higher period of the average increasing rate. From 25m to 46m, the average concentration was 0.034mg/m3, variation range was 0.032mg/m3, and the average increasing rate was 1.16×10-3mg/m3, which was the lower period of the average increasing rate.In May, ozone concentration in the vertical direction could be divided into two heights, the dividing point was 22m. From 1m to 22m, the average concentration was 0.033mg/m3, variation range was 0.027mg/m3, and the average increasing rate was 1.92×10-3mg/m3, which was the higher period of the average increasing rate. From 25m to 46m, the average concentration was 0.047mg/m3, variation range was 0.037mg/m3, and the average increasing rate was 1.47×10-3mg/m3, which was the lower period of the average increasing rate.(5)In the development zone of Baoji in April and May 2015, the concentration of nitrogen oxides and ozone had positive correlation with temperature, correlation coefficients were 0.36 and 0.41; nitrogen oxides and ozone had negative correlation with relative humidity, correlation coefficients were -0.26 and -0.14; nitrogen oxides and ozone had negative correlation with air pressure, but not pass the significant level of 0.05; nitrogen oxides and ozone had negative correlation with wind speed, but correlation between ozone and the wind did not pass the level of 0.05,the correlation coefficient of the nitrogen oxides and wind speed was -0.22; the concentration of nitrogen oxides had negative correlation with sun radiation, but not pass the significant level of 0.05, the concentration of ozone had positive correlation with sun radiation, correlation coefficients was 0.97; nitrogen oxides and ozone showed negative correlation, but not pass the level of 0.05.(6)The paper adopted atmosphere pollution index (API) to evaluate the atmosphere environment quality of development zone of Baoji in April and May. The results showed that the air quality in April and May were good and moderate, the overall situation was ideal.(7)We establish multiple linear regression mode to write regression equation: YNOX=-0.363-0.042XO3+0.023XT-0.015XRH-0.039Xp-0.049Xws-8.376×10-5XSR, Yo3=1.103-0.011XNOX+0.004XT-0.002XRH-0.006Xp-0.13Xws+1.154×10- XSR, and through the test concluded that the model could be used for the prediction of nitrogen oxides and ozone concentration. |
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