大气可吸入肺纳米颗粒的SEM及X射线微分析研究

摘要

以大气中可吸入肺纳米颗粒为研究对象，利用场发射扫描电子显微镜（FSEM ）和X射线能谱仪对其形态和常量组分进行了系统研究。研究结果表明：大气可吸入物中的纳米颗粒大多为类球与椭球形，表面较为光滑，结构紧密，较小的纳米颗粒聚集成团呈松散絮状，粒度大小约在30～100 nm之间，纳米颗粒物中含有的常量元素同大颗粒污染物基本一致，主要含有C ，O ，Al ，Si ，Na ，M g ，K ，Ca ，Fe ，S ，Cl等元素，能量色谱仪（EDS）的点分析研究证实一些纳米颗粒物中Cl和S元素的含量明显增大，而另一些颗粒主要为C和O元素，分析其原因，认为主要是气溶胶在形成过程中，以纳米无机灰尘颗粒为中心表面吸附了大气污染物中的有机排放物所致，从而形成了具有核壳结构的纳米颗粒污染物。因此，减少人为有机污染物的排放，对于减少可吸入肺有害纳米颗粒的形成具有很大的影响。%Inspirable nano-particles into lungs in the atmosphere were studied in this paper .Field emission scanning electron mi-croscope (FSEM ) and X-ray energy dispersive spectrometer were used to investigate the morphology and major constituents of inspirable nano-particles into lungs systematically .The results showed that most of the inspirable nano-particles in the atmos-phere are spherical and ellipsoidal ,with smooth surface and dense structure .The smaller nano-particles are clustered into loose floccule ,with the sizes in the range of 30 to 100 nm .The constant elements in the nano-particles are close consistent with the large particle pollutants ,which mainly contain C ,O ,A1 ,Si ,Na ,Mg ,K ,Ca ,Fe ,S and Cl etc .The point Analysis of EDS confirmed that the element content of Cl and S in some nano-particles is significantly increased ,while others mainly contain C and O .It is believed that the surface of nano inorganic dust particles was adsorbed by the organic pollutants to form the core-shell structure nano-particles pollutants in the process of aerosol formation .Thus ,reducing anthropogenic emissions of organic pollu-tants has great influence on the formation of inspirable nano-particles .