对流层平流层气溶胶粒子的形态和化学组成

MORPHOLOGICAL FEATURE AND CHEMICAL COM POSITION OF INDIVIDUAL PARTICLES IN THE TROPOSPHERE AND STRATOSPHERE

  • 摘要: 分析研究了1993年和1994年的8月、9月在香河地区上空采集的单个气溶胶粒子的形态及化学元素和化合物的组成。结果表明:1993年,在对流层大气中的气溶胶颗粒经常出现不规则形的粒子,可能是土壤粒子;而在平流层大气中的颗粒以具有“卫星”结构的硫酸粒子为主;硫酸铵粒子则经常出现在对流层的中、下部。香河地区上空颗粒物的化学元素组成比较复杂,单一化学元素组成的粒子较少,粒子主要含有Si,Fe,Al和S等元素。气溶胶的化合物有硫酸盐、硅酸盐、硝酸盐和磷酸盐等。

     

    Abstract: The collection of aerosol particles was carried out at Xianghe Scientific Balloon Observatory (39. 45°N, 117°E), Hebei province, China during Augusts and Septem bers of 1993 and 1994. The individual particles were collected on carbon-and Aluminium-coated films by a balloonborne impactor. A scanning electron microscope(SEM) equipped with an energy-dis-persive X-ray analyzer (EDXA) was applied to analyze the particles' morphologies and elemental compositions. The compounds of particles were examined with a laser microprobe mass spectrometer(LAMMS). Main results show as follows: (1) Irregular shape soil particles were frequently presented in the free troposphere. And in the stratosphere, the major particles had "satellite structure", which had been recognized as typical sulfuric acid droplet. Ammonium sulfate particles were of ten identified in the low-midtroposphere. (2) The elements of Si, Fe, Al and S were dominant constituents in particles. There were some" Si-rich" mineral particles even up to 20 km. (3) Not so many "Ca-rich" particles were shown during the experiment period. This implied that the particles came mainly from the locality, not from desert and loess areas. (4) The elements of Pand Niwere detected in particles. This is corresponding to the results of Beijing's particles collected near ground and Texas, American in 34~36 km, but the elements were not identified in Japan and American's particles collected in surface layer. (5) The compounds of individual particles contained mainly silicate, sulfate, nitrate and phosphate, and their changes with time and altitude were obvious. (6) It was found that the particles contained sulfate and nitrate or nitrate and phosphate meantime. It was difficult to comment this phenomenon. And the abundance values of nitrate, sulfate and silicate seemed bigger. (7) The chemical elements of particles were complex over Xianghe region.

     

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