Collaborative Research: Investigations into the Temporal & Source-Dependent Chemical Compositions & Reactivity of Natural Dissolved Organic Matter

在本项目中，美国Old Dominion大学和俄亥俄州立大学的研究人员将把天然溶解有机物（DOM）的分子水平化学特征的测定与DOM与模型化合物的反应性的定量研究结合起来。他们的初步工作表明，季节和来源导致的DOM成分差异会影响天然水体的总体化学性质，从而导致特定化合物的溶解度等变化。该团队将调查DOM的组成和反应性随季节（超过2.3年）、有机物来源（从上游黑水河到沿海海洋的6个地点）和水化学（pH值、盐度等）的变化。严格的采样制度，结合实验室工作，旨在详细说明DOM的总体化学成分和反应性，将允许更全面的DOM化学和与人为化合物相互作用的定量模型。作为这项工作的一部分，研究人员计划使用NMR， IR， HLPC和几种质谱方法来全面表征DOM，并使用NMR和IRMS定量跟踪其与同位素标记的模型化合物的化学相互作用。更广泛的影响：这项研究将在水生/海洋和分析化学、污染物运输和水系统中人为化合物的影响以及有机物的封存和保存等领域提供重大进展。老道明大学和俄亥俄州立大学都致力于培养毕业生、本科生和K-12学生。这项工作将为三名研究生提供直接支持，他们的论文主题将集中在DOM表征，变异性和分子相互作用方面。本科生将接受先进的分析和仪器技术以及对其结果的解释方面的培训。该项目还将通过与美国国家科学基金会赞助的俄勒冈州立大学海洋科学和俄勒冈州立大学环境分子科学的REU-MUST项目的合作而得到加强。

ABSTRACTOCE-0453777 / OCE-0453743In this project, investigators at the Old Dominion University and the Ohio State University will integrate the determination of molecular-level chemical characteristics of natural dissolved organic matter (DOM) with investigations that quantitatively explore the reactivity of DOM with model compounds. Their preliminary work shows that compositional differences in DOM attributed to both season and source can influence the bulk chemical properties of natural waters so as to induce changes in, for example, the solubility of specific compounds. The team will investigate changes in composition and reactivity of DOM as a function of season (over 2.3 years), organic matter source (6 sites from upstream blackwater rivers to the coastal ocean) and water chemistry (pH, salinity, etc.). A rigorous sampling regime, combined with laboratory work designed to detail both the bulk chemical composition and reactivity of the DOM will allow for more comprehensive quantitative models of DOM chemistry and interactions with anthropogenic compounds. As part of this work, the researchers plan to use NMR, IR, HLPC and several mass spectral approaches to fully characterize the DOM and use NMR and IRMS to quantitatively follow its chemical interactions with isotopically labeled model compounds.Broader Impacts: This study will provide significant advancements in the areas of aquatic/marine and analytical chemistry, contaminant transport and the impact of anthropogenic compounds in aqueous systems and organic matter sequestration and preservation. Both Old Dominion University and Ohio State University are strongly committed to the training of graduates, undergraduates and K-12 students. This work will provide direct support for three graduate students whose dissertation topics will be centered in DOM characterization, variability and molecular interactions. Undergraduate students will be trained in advanced analytical and instrumental techniques as well as in the interpretation of their results. The project will also be augmented through association with the NSF-sponsored REU-MUST program in ocean science at ODU and environmental molecular science at OSU.