Volatile Polonium and Tellurium Species in the Marine Environment

海洋环境中的挥发性钋和碲物质

• 批准号: 0425199
• 负责人: Thomas Church
• 金额: --
• 依托单位: University of Delaware
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0425199&HistoricalAwards=false
• 关键词: Volatile; Polonium; Tellurium; Species; Marine

ABSTRACTOCE-0425199In this project, researchers at the University of Delaware will study the formation of volatile polonium (Po) and tellurium (Te) species in marine environments. These two elements may provide a metric of air-sea metalloid evasion using the natural radionuclide 210Po by comparison to its stable Group XVI congener Te. The basic chemical properties of polonium and tellurium suggest that alkylation will occur via common reactions, and strong field evidence exists for the production of volatile species of both elements in marine environments. However, volatile species have not yet been directly observed in marine systems. The researchers hypothesize that stable alkyl species of polonium and tellurium contribute to their volatile flux across the marine atmospheric boundary. This hypothesis will be tested through analytical development, laboratory reactions, microbial methylation assays, and field sampling studies leading to the first direct volatile species identification in the marine environment. Analytical methods will be developed including GC-ICPMS technologies for species separation and identification. Laboratory studies will test for alkylated products of abiotic methylation reactions, and microbial cultures grown for biotic generation of volatile tellurium and polonium species. Finally, both head space analysis in batch incubation of natural sediments and downwind of marine areas with expected methylation activity will be sampled for naturally occurring volatile products of polonium and tellurium. Broader Impacts: This project will deal with globally significant biogeochemical processes that include potential pollutant transfer and marine biotic stress. Graduate and post-graduate students will gain experience developing next generation analytical techniques to address such processes. Undergraduate students will participate in the NSF-sponsored research resulting in educational and professional experiences by exposure to the proposed research under the NSF-REU (Research Experience for Undergraduates) program.

在这个项目中，特拉华州大学的研究人员将研究海洋环境中挥发性钋（Po）和碲（Te）的形成。这两种元素可以提供一个度量的空气-海洋类金属逃逸使用天然放射性核素210 Po相比，其稳定的第十六族同族Te。 钋和碲的基本化学性质表明，烷基化将通过常见的反应发生，并存在强有力的现场证据表明，这两种元素在海洋环境中的挥发性物质的生产。 然而，挥发性物种尚未在海洋系统中直接观察到。 研究人员假设，稳定的烷基物种的钋和碲有助于他们的挥发通量通过海洋大气边界。 这一假设将通过分析开发、实验室反应、微生物甲基化测定和实地取样研究进行检验，从而首次直接查明海洋环境中的挥发性物种。 将开发分析方法，包括用于物种分离和鉴定的GC-ICPMS技术。 实验室研究将测试非生物甲基化反应的烷基化产物，以及为生物生成挥发性碲和钋物种而培养的微生物。 最后，将对天然沉积物分批孵育中的顶空分析和具有预期甲基化活性的海洋区域的顺风进行采样，以获得天然存在的挥发性钋和碲产品。更广泛的影响：该项目将处理全球重要的生物地球化学过程，包括潜在的污染物转移和海洋生物压力。研究生和研究生学生将获得开发下一代分析技术来解决这些过程的经验。本科生将参加NSF赞助的研究，通过接触NSF-REU（本科生研究经验）计划下的拟议研究，获得教育和专业经验。