Seasonal Distribution And Source Analysis Of Water-soluble Inorganic Substances In Different-size Particle In Xinxiang

ObjectiveTo explore sources and seasonal distribution of PM in different particle sizes in Xinxiang city.MethodWe collected atmospheric particulates matters by an Anderson 8-stage sampler from different seasons for all 53 days in Xinxiang medical university.Mass concentration of size-segregated PM was calculated by gravimetric analysis.Water-soluble ions(Cl^-,F^-,SO₄^2-,NO₃^-,K⁺,Na⁺,Ca²⁺,Mg²⁺,NH₄⁺)and water-soluble metals?Al,Mn,Cr,Cd,As,Ni,Cu,Pb?were analyzed by ion chromatography and inductively coupled plasma-mass spectrometry respectively,and then principal component analysis was used to analyze the source of water-soluble ions.Results and Discussion1.The mass concentrations of particulate matters had a bi-modal distribution,peaks ranging from 0.65 to 2.1?m and 5.8 to 10?m,and seasonal distribution was the autumn>winter>spring>summer.2.Seasonal distribution of total water-soluble ions was autumn>winter>spring>summer.3.The mass concentrations of water soluble ions from highest to lowest were NO₃^-,SO₄^2-,NH₄⁺,Ca²⁺,Cl^-,K⁺,F^-,Na⁺,Mg²⁺,and there was no obvious differences between seasonal distributions of ions.4.Size distribution of every single water soluble ions was follows?1?Mg²⁺,Ca²⁺,F^-had a bi-modal distribution,peaks ranging from 3.3 to 4.7?m and 5.8 to 9.0?m.?2?NH₄⁺,NO₃^-and SO₄^2-were unimodal distribution,gathering from 0.65 to 1.1?m.?3?K⁺and Cl^-were unimodal distribution,peak ranging from 1.1 to 2.1?m.?4?Na⁺had a multi-mode distribution,with peaks ranging from 1.1 to 2.1?m,from 3.3 to 4.7?m and from 9.0 to 10.0?m respectively.5.Mn distribution is bimodal,mainly gathering from 0.65 to 1.1 and 9.0 to 10?m;Al is multi-peak distribution,mainly gathering in coarse particle size;Ni is unimodal distribution,mainly gathering in the coarse grain size;Cu,Cd,Pb is unimodal distribution,the main gathering in 1.1 to 2.1?m;As was unimodal distribution,mainly gathering from0.65 to 1.1?m.6.Water-soluble metal distribution has obvious seasonal difference.As and Cr performance for fall significantly higher than other seasons;the season performance for Al is autumn>spring>winter>summer;Mn,Ni,Pb performance for winter>spring>autumn>summer;Cu performance for the winter>autumn>spring>summer;Cd is significantly higher in spring than other seasons.7.The total water soluble metal elements gathering from 1.1 to 2.1?m,2.1 to 3.3?m,3.3 to 4.7?m in spring,summer and winter,while they are highest at 4.7 to 5.8?m in autumn.8.Principal component analysis results showed that the burning blended with thesecondary pollution of vehicle exhaust source was a common major source in every particle size,and the source of contribution rate with the increase of particle size tended to decrease.The contribution rate of construction dust was increase with the increase of particle size.9.NO₃^-/SO₄^2-ratio scaled up with the increase of particle size,summer was not included;and NO₃^-/SO₄^2->1 in fine particulate matter,and NO₃^-/SO₄^2-<1 in coarse particulate matter.10.CE/AE<1 in fine particulate matter,while CE/AE>1 in coarse particulate matter.11.Atmospheric pressure,NO₂,SO₂ and CO were positively correlated with fine particle size,while outdoor temperature and O₃ concentration were negatively correlated significantly.DiscussionWater-soluble inorganic seasonal difference was bigger in different particle size of the atmospheric particles,and the overall performance in fall and winter were higher than spring and summer.The content of water-soluble inorganic substances in fine particulate matter was higher than that of water-soluble inorganic substances in coarse particulate matter.Mixed source of mobile source represented by automobile exhaust and the combustion were the main sources of particulate matter in Xinxiang.