Measurements of properties of marine aerosols on research vessel

由于室内和室外样品的湿度不同，在实验室内测量大气气溶胶的谱分布是困难的。样品在过滤器上的伪影也是化学分析中的一个严重问题。为了解决湿度对粒度测量的影响问题，使用了两种系统来测量干燥和潮湿条件下的粒度分布（Miura）。通过水透析（Niimura和Miura）检查单个颗粒的混合物结构。为解决硫酸盐和硝酸盐浓度的伪影问题，采用真实的时间分析仪（植松）连续测量。本文对大陆气团（小岛）的氡浓度进行了连续观测，主要结果如下：1。采用TDMA方法研究了海洋亚微米颗粒物的湿特性。海洋气溶胶的生长分数几乎为100%，生长因子略小于NaCl。但这些气溶胶的潮解湿度与NaCl的潮解湿度一致。气溶胶的增长因子和增长分数受大陆气团的影响而减小。这些特性取决于气溶胶源和天气条件.通过TEM、EDX和水透析的组合研究了单个颗粒的混合性质。对于在北太平洋上空收集的颗粒物，元素分析表明，大部分颗粒物含有水溶性物质。在所有颗粒中，“混合”颗粒的数量分数在40%至80%的范围内。对东海海域大气颗粒物的元素分析表明，科萨事件的“混合”颗粒物的数量分数是非科萨事件的2 ~ 3倍。这些结果表明，海洋大气中的煤烟或Kosa粒子与水溶性物质的混合，当空气质量从大陆输送。

It is difficult to measure the size distribution of atmospheric aerosol in laboratory because humidity of sample is different between outdoor and indoor. The artifact of sample on the filter is also a sever problem in chemical analysis.To solve the problem of the humidity effects on size measuring two systems were using to measure size distribution in dry and wet conditions (Miura). An intermixture structure of individual particles was examined by a water dialysis (Niimura and Miura). To solve the problem of the artifact sulfate and nitrate concentration were measured with real time analyzer continuously (Uematsu). Radon concentration was measured continuously as a tracer of continental air mass (Kojima).Main results are as follows :1. Humidity properties of marine submicron particles were investigated with the TDMA. Growth fraction of marine aerosol was almost 100 % and growth factor was a little smaller than that of NaCl. But the deliquescence humidity of these aerosols agreed with that of NaCl. Growth factor and growth fraction of aerosols decrease as they are affected by continental air mass. These properties are dependent on aerosol sources and weather condition.2. The mixing properties of individual particles were studied by using a combination of TEM, EDX and a water dialysis. For the particles collected over the North Pacific, the elemental analysis showed that most of particles contained water-soluble material. A number fraction of "Mixed" particles in all particles ranged from 40 to 80%. For particles collected over the East China Sea, the elemental analysis showed that a number fraction of "Mixed" particles of Kosa event was twice or three times that of non-Kosa event. These results imply that marine atmosphere is influence by soot or Kosa particles mixed with water-soluble materials, when the air mass is transported from the Continent.