Permalink : http://hdl.handle.net/2115/55013

大気エアロゾル粒子の水溶性成分含有率（ε）は,粒子の吸湿性や雲粒への活性化に関わる重要なパラメーターであるが,実測例は限られている.そこで,共焦点レーザー顕微鏡を用いた粒子体積の計測と水透析法とを組みあわせた手法により,黄砂粒子標準物質（CJ1とCJ2）と名古屋で採取した個別粗大ダスト粒子について,球相当径で約１～８μmの粒子を解析し,εを求めた.CJ1とCJ2の平均εは,それぞれ29％と13％だった.名古屋における２回の黄砂時の粗大粒子について,平均εは18～42％であり,発生源域での値よりも高い場合があった.εの高いダスト粒子は,巨大CCN として働く可能性があるので,日本付近で高εダスト粒子が増えれば,巨大CCN数も増えるかもしれない.
The volume fraction(ε)of water soluble material in atmospheric aerosol particles is an important parameter related to their hygroscopicity and activation processes to form cloud and ice particles. To estimateεof coarse dust particles,confocal scanning laser microscope was applied to measure the volume difference of individual particles before and after water dialysis directly. Individual particles(sphere equivalent diameter approx.1-8 μm)of Asian reference dusts(CJ1 and CJ2)and atmospheric coarse particles during four Asian dust events were analyzed to ascertainε. Median values ofεfor CJ1 and CJ2 were,respectively, 29% and 13% with no size trend. Median values ofεfor coarse aerosol particles during two dust events were 18-42%. Dust particles with high εare potentially important for acting as giant CCN. Therefore aging of dust particles during transport might enhance the number of giant CCN over the North Pacific.