Ice core dust particulate by XPS-SEM/EDAX——Impact of dust particulate on SO_4^(2-) record in ice cores

查看全文 作　　者：LI Zhongqin , LU Gongxuan , LIU Baozhong , FU Hongxiang LIU YuTianshan Glaciological Station , Lanzhou Institute of Glaciology and Geocryology , Chinese Academy of Sciences , Lanzhou 730000,China ;State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics , Chinese Academy ofSciences , Lanzhou 730000, China, 出　　处：《Chinese Science Bulletin》索引1999年第44卷第15期,共4页 摘　　要：The ice core dust particulate sampled from Mt. Xixabangma has been analyzed by means of X-ray photoelectron spectrometer (XPS) and scanning electron microscope with energy dispersion X-ray analysis (SEM/EDAX). The results show that the contents of SO₄^2- and SO₃^2- in the surface layer of the dust are significantly higher than those in the subsurface layer (with the exception of organic sulfide). This difference indicates that the surface SO_x has been captured and then chemically converted by the atmospheric dust particulate before its deposition with snow, which is obviously different from those inner layer sulfates and sulfites contained by dust itself. In addition, it has been determined by SEM/EDAX that the dust contains relatively high concentrations of transition metal elements such as Fe and Ti oxides which could function as photocatalysts to the conversion of SO_x adhered on the surface of the dust, and consequently accelerate the deposition of SO_x to snow. Our research also 关 键 词：ice core RECORDS DUST partculate SULFATE ions.