Studies on chemistry and cycles of halogens in the troposphere

对流层中卤素的化学和循环研究

基本信息

批准号：
10144101
负责人：
KAWAMURA Kimitaka
金额：
$ 81.02万
依托单位：
HOKKAIDO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research on Priority Areas (A)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10144101/
关键词：
Halogen Chlorine Bromine Aerosols Photochemical reaction Marine atmosphere Seawater Troposphere 対流圏

项目摘要

In this program, we conducted several projects. They include (l) measurements of inorganic halogens and their atmospheric behaviors, (2) development of halogen measurement and its application to the atmosphere, (3) atmospheric behaviors of halogenated volatile hydrocarbons, (4) halogenated organics in aerosols and analysis of organic aerosols, (5) carbon isotopic analysis of non-methane hydrocarbons, (6) dynamics and interaction of halogens in air/water interface, and (7) formation mechanism and cycles of biogenic halocarbons.We made a new analytical system to measure hologen gases by using scrubber technique. By using this method, a formation of halogen gases from the sea salt particles was observed. We also observed a decrease in the concentration of Cl^2 and an increase of HCl gas in daytime in the marine atmosphere. A chemical ionization mass spectrometer that was designed for the measurement of Br^2 and Cl^2, has been made in this study. Using this instrument for laboratory experiment, we observed the formation of Br^2 gas on the surface of sea salt particles as a result of Cl uptake. We also confirmed the release of halogen gases from the sea salts by the reaction with ozone. Seawater and air samples collected from the Pacific Ocean were analyzed for holocarbons using a purge and trap GC/mass spectrometry. We found a seasonal change of halogen compounds with maxima in August/September in the western North Pacific. In the marine aerosols, we identified, for the first time, halogenated organic acids and aldehydes, including bromosuccinic and chlorosuccinic acids. The former acid showed higher concentrations in the western North Pacific near Asia continent, whereas the latter increased in the central Pacific. Based on the observations over the Pacific, we proposed a photochemical formation model for the newly rescovered halogenated organic compounds and an evolution model of organic aerosols.

在此计划中，我们进行了几个项目。 They include (l) measurements of inorganic halogens and their atmospheric behaviors, (2) development of halogen measurement and its application to the atmosphere, (3) atmospheric behaviors of halogenated volatile hydrocarbons, (4) halogenated organics in aerosols and analysis of organic aerosols, (5) carbon isotopic analysis of non-methane hydrocarbons, (6) dynamics and interaction of空气/水界面中的卤素，以及（7）生物卤代碳的形成机制和周期。我们通过使用洗涤塔技术制定了一种新的分析系统来测量全息气体。通过使用这种方法，观察到来自海盐颗粒的卤素气体形成。我们还观察到Cl^2的浓度降低，在海洋大气中白天的HCl气体增加。在本研究中，已经设计了用于测量Br^2和Cl^2的化学电离质谱仪。使用该仪器进行实验室实验，我们观察到由于CL摄取而在海盐颗粒表面形成了Br^2气体。我们还通过与臭氧反应从海盐中释放出卤素气体。使用清除和诱捕GC/质谱法分析了从太平洋收集的海水和空气样品。我们在八月/9月在北太平洋西部发现了卤素化合物的季节性变化。在海洋气溶胶中，我们首次鉴定出卤代有机酸和醛，包括溴糖核酸和氯糖酸。前者酸在亚洲大陆附近的北太平洋地区显示出较高的浓度，而后者则在中太平洋中有所增加。基于对太平洋的观察结果，我们提出了一个新化的卤代有机化合物和有机气溶胶的进化模型的光化学形成模型。