CAREER: Molecular-Level Behavior of Chromophores in Dissolved Organic Matter

在化学学部环境化学科学项目的支持下，德克萨斯农工大学的Garrett McKay教授将研究溶解有机物质中吸收光的化合物的化学结构。溶解有机质是地球上最丰富的碳源之一，与阳光的相互作用对这种碳在环境中的循环起着重要作用。利用先进的分析工具和光谱学，该项目将确定溶解有机物中吸收光基团的结构成分，以及这些基团相互作用的程度。了解这些吸收光的基团如何相互作用将提高预测环境中溶解有机物的命运和反应性的能力。除了对本科生和研究生的培训外，一个教育推广项目，包括Lufkin高中（Lufkin， TX）的水生科学课程，将为代表性不足的群体的学生提供一个机会，使用最先进的技术研究当地水体中溶解的有机物质发色团。溶解有机物中发色团的结构控制着水生系统中关键过程的机制和速率，如元素循环、污染物的衰减和地球海洋的生产力。然而，形成DOM光学和光化学性质的过程的知识仍然难以捉摸。本研究将结合质谱、电化学和多光谱分离技术来揭示溶解的有机物质发色团之间供体-受体相互作用的普遍性和组成。用精心选择的模型化合物进行的研究也将用于评估这些相互作用的结构驱动因素。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

With support from the Environmental Chemical Sciences Program of the Chemistry Division, Professor Garrett McKay of Texas A&M University will study the chemical structure of light-absorbing compounds in dissolved organic matter. Dissolved organic matter is one of the most abundant carbon sources on earth, and interaction with sunlight plays an important role in cycling this carbon in the environment. Using advanced analytical tools and spectroscopy, the project will determine the structural components of light-absorbing groups in dissolved organic matter and the extent to which these groups interact with one another. Understanding how these light-absorbing groups interact will improve the ability to predict the fate and reactivity of dissolved organic matter in the environment. In addition to training of undergraduate and graduate students, an educational outreach program, involving Lufkin High School’s (Lufkin, TX) Aquatic Science course, will give students who are members of underrepresented groups an opportunity to study dissolved organic matter chromophores in a local water body using state-of-the art techniques.The structure of chromophores in dissolved organic matter governs the mechanisms and rates of key processes in aquatic systems, such as elemental cycles, attenuation of contaminants, and productivity of the Earth’s oceans. However, knowledge of the processes that shape DOM’s optical and photochemical properties remains elusive. This research will combine mass spectrometric, electrochemical, and separation techniques with multiple spectroscopies to unravel the prevalence and composition of donor-acceptor interactions between dissolved organic matter chromophores. Studies conducted with carefully chosen model compounds will also be used to evaluate the structural drivers of these interactions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.