Photochemical Fate of Dissolved Amino Acids in Natural Aquatic Environment

这个奖项从环境化学科学计划在化学部支持教授。密歇根理工大学的Daisuke Minakata和Paul Doskey。他们研究自然淡水中的游离氨基酸与光的反应。理解和预测这些过程是重要的，因为含氮游离氨基酸及其降解产物参与全球氮循环。它们还影响自然水生环境中的生物活动。废水的流出物含有氨基酸作为主要成分之一。这项研究的结果解决了含氮污染物对接受处理过的城市废水的水生系统的影响。该项目包括通过暑期青年实习生计划向底特律地区的K-12高中学生开展外联活动。该计划促进了环境科学领域代表性不足的群体的参与和保留。正在根据这项研究的结果开发一个网络研讨会，以提高公众对淡水系统中的水安全和保障以及保护生态系统免受污染物影响的重要性的认识。该奖项支持计算和实验研究和教育，以预测游离氨基酸转化的光解和基本反应途径。这种转变是由直接光解和间接氧化的光化学反应产生的活性中间体。研究人员使用计算化学工具来确定代表性游离氨基酸转化的基本基本反应途径。然后，研究小组预测每个确定的基本反应途径的动力学信息。最后，基于基元反应的动力学模型被开发用于预测环境相关条件下游离氨基酸及其转化产物的时间依赖性浓度分布。预测的浓度分布进行比较，实验室规模的实验观测，以验证动力学model.This奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

This award from the Environmental Chemical Sciences Program in the Division of Chemistry supports Profs. Daisuke Minakata and Paul Doskey from Michigan Technological University. They study the reactions of free amino acids in natural freshwater with light. Understanding and predicting these processes is important because nitrogen-containing free amino acids and their degradation products are involved in global nitrogen-cycling. They also affect biological activity in natural aquatic environments. The effluent of wastewater contains amino acids as one of the major components. The findings from this study address the impact of nitrogen-containing contaminants to aquatic systems that receive treated municipal wastewater. The project includes outreach activities to K-12 high school students in the Detroit region through a summer youth intern program. This program promotes the participation and retention of underrepresented groups in the environmental science field. A webinar is being developed based on the findings of this study to raise public awareness of water safety and security in freshwater systems and the importance of protecting ecosystems from contaminants. This award supports computational and experimental research and education to predict the photolytic and elementary reaction pathways of free amino acid transformation. This transformation is induced by direct photolysis and indirect oxidation by photochemically produced reactive intermediates. The researchers use computational chemistry tools to identify the fundamental elementary reaction pathways of representative free amino acids transformation. The research team then predicts the kinetics information of each identified elementary reaction pathway. Finally, a kinetic model based on elementary reactions is developed to predict the time-dependent concentration profiles of free amino acids and their transformation products in environmentally relevant conditions. The predicted concentration profiles are compared to laboratory-scale experimental observations to validate the kinetic model.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.