摘要
汞同位素自然库存作为对汞污染源进行准确示踪的基础,对其进行完善仍是汞同位素研究领域的工作重点。汞存在7种稳定同位素且兼具质量分馏和非质量分馏效应,通过汞同位素对污染源、汞迁移转化过程进行示踪成为理想途径。库存数据作为汞同位素研究的基础,借助多道接收电感耦合等离子质谱仪(MC-ICPMS)对汞同位素进行精确测试,汞同位素库存研究领域取得了显著成果。表现如下:自然界不同库存汞同位素数据库已经初步建立;不同环境汞同位素组成差异显著且同一环境下不同样品同位素组成也各不相同,对其形成机理有了初步认知;依据汞同位素在不同环境的分馏特点及不同库存同位素组成特征,研究者开始对汞污染源进行示踪探索并取得了成功;自然界一些涉及汞迁移、转化的过程,同位素分馏特征已被掌握,特别是奇数非质量分馏的典型过程(光致还原、吸附)已被用于判别汞的地球化学迁移转化过程。涉及煤火的表生态汞的迁移转化是复杂的,部分汞具有二次释放特性,其中汞同位素产生的分馏效应无疑使通过同位素研究对汞污染源进行准确示踪变得困难,因此涉及煤火的表生态汞地球化学特征可作为汞同位素研究领域的一个新的方向。
As the basis of accurate tracing back mercury pollution sources,the mercury isotope natural database and its complementis still the focus in the mercury isotope research field.Mercury has7stable isotopes,which are both mass-dependent fractionation(MDF)and mass-independent fractionation(MIF),making it an ideal way to trace mercury sources and mercury migration and transformation processes.The study of Hg isotope database has achieved significant progress by using the multiple collector inductively coupled plasma-mass spectrometry(MC-ICP-MS)to accurately test mercury isotopes.The summaries are as follows:the database of natural sample Hg isotope is initially established.The composition of mercury Isotopes varies with the change of samples and environments.It has a preliminary understanding of isotope fractionation mechanism.And mercury isotopes have been successfully used to track sources and geochemical pathways of Hg in the environment.Fractionation characteristics have been mastered in some natural processes,especially the typical process of MDF and MIF(photo-reduction,adsorption),which has been used to determine the geochemical transformation of mercury.The migration and transformation of the coal fire surface mercury is complex because partial mercury on the surface may come up secondary release.This fractionation process of mercury isotope has no doubt made it difficult to trace the pollution source by isotope studies.So mercury isotope geochemistry characteristics in the coal fire area may be a new direction in the mercury isotope research field.
作者
李春辉
汪婷
梁汉东
施云云
曹庆一
LI Chunhui;WANG Ting;LIANG Handong;SHI Yunyun;CAO Qingyi(State Key Laboratory of Coal Resoures and Safe Mining//China University of Mining and Technology, Beijing 100083, China;College of Geoscience and Surveying Engineering, China University of Mining and Technology(Beijing), Beijing 100083, China)
出处
《生态环境学报》
CSCD
北大核心
2017年第9期1627-1638,共12页
Ecology and Environmental Sciences
基金
国家自然科学基金项目(41371449)
关键词
汞同位素
分馏效应
自然库存
地球化学示踪
mercury isotopes
fractionation effect
mercury isotope database
geochemical tracer
