Speciation of hygroscopic species in aerosols by X-ray microscopy for the precise prediction of global warming

2015 Fiscal Year Final Research Report

• Project/Area Number: 25550013
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Environmental dynamic analysis
• Research Institution: The University of Tokyo (2014-2015); Hiroshima University (2013)
• Principal Investigator: Takahashi Yoshio 東京大学, 理学(系)研究科(研究院), 教授 (10304396)
• Co-Investigator(Kenkyū-buntansha): NITANI Hiroaki 高エネルギー加速器研究機構, 物質構造科学研究所, 助教 (20554603)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 化学種解明 / XAFS / エアロゾル / STXM / カルシウム / 硫黄

Outline of Final Research Achievements

Evaluation of hygroscopic characteristics of aerosols is very important for the precise prediction of global warming effect. To understand the cooling effect of hygroscopic aerosols that can become cloud condensation nuclei (CCN), precise determination of chemical species such as sulfate and organic matter is important. For this purpose, scanning transmission X-ray microscopy (STXM) is a powerful tool that can identify various chemical species with spatial resolution better than 50 nm. The application of STXM in a new beamline BL-15A was developed in Photon Factory in this study. We have also employed a new STXM system for the determination of sulfur and calcium species in aerosols. As a result, identification of sulfate and oxalate species was identified for calcium species in aerosols that should be produced by the neutralization of calcium carbonate in mineral aerosols. As for the speciation of sulfur, ammonium and calcium salt for sulfate species was identified in aerosols.

Free Research Field

地球化学、環境化学