Analysis On PM_2.5, PM₁₀ Characteristics And Dust Fall Properties Of Hohhot

In recent years,environmental problem caused by air particles has become a hot topic,caused great concern in China,especially the effect of particles concentration on the urban environment.Therefore,this paper chooses Huhhot city as the study area,which researches mainly concentrations characteristics and pollution degree of PM2.5 and PM10.The relationships between mass concentration of PM2.5,PM10 and temperature,air pressur,wind speed,relative humidity are analyzed.In addition,the scanning electron microscopy method is used to observe morphology of atmospheric particles,and the heavy metal contents and total nitrogen,total phosphorus,total potassium content are measured by the experimental method to reveal physical and chemical properties of dustfall.Get the following conclusion:Distributions of concentration variation of PM2.5 and PM10 are irregular over time.The season order of PM2.5 concentration is winter> autumn>spring>summer,and the order of PM10 concentration is winter>spring>autumn>summer.Month of the biggest concentrations is December,Month of the minimum concentrations is August.Overall,PM2.5 and PM10 concentration in urban ia greater than Helingeer.Days of Pollution is more in urban areas,and the air quality is better in Helingeer county.Distributions of concentration variation of PM2.5 and PM10 are uneven in the day in Hollinger Shengle economic development area, being the morning>noon>afternoonThe relationship between mass concentration of PM2.5,PM10 and temperature,temperature is negative,and air pressure is positive; Relative humidity takes 60% as the boundary,less than 60% is positive, more than 60% is negative correlation;when the wind speed is less than or equal to 2.5m/s,relationship is negative,when the wind speed is more than 2.5m/s,relationship between mass concentration of PM2.5 and the wind is negative,relationship between mass concentration of PM10 and the wind is positive.By electron microscope particles of irregular shapes are the most. There are also chain,fluffy,regular shapes,such as rectangles and ball etc;The vast majority of particle size is 50um-250um,followed 10um-50um,1um-2.5um is least within the range. The proportion of PM1.0 is 12.38% in the atmosphere dust,PM2.5 accounted for 14.43%,and PM10 accounted for 19.92%.large particles are main proportion in atmospheric dust about sand dust storm weather.Distribution of heavy metal elememts contents is uneven in Hohhot,and the order of enrichment degree is Cr>Cu>Pb>Mn. Enrichment coefficients of Cr are more than 10,so source is man-made source. Enrichment coefficients of Mn,Pb,Cu are more than 1 and less than 10,so sources of Mn include natural sources and man-made sources.In Hohhot the content of total nitrogen,total phosphorus and total potassium have no significant differences.The order of content is the Saihan district>the new district>the Shengle economic development area.