CAREER: Understanding Molecular-level Processes of Gas-phase Ammonia Uptake by Aqueous Sulfuric Acid Surfaces using Broadband Sum Frequency Generation Spectroscopy

俄亥俄州立大学的Heather Allen教授获得了分析和表面化学计划颁发的CAREER奖，用于气液表面的和频率生成研究，特别是环境方面的研究。将使用宽带SFG研究硫酸水溶液表面对氨的吸收，从而获得特定于表面区域的振动谱。光谱将被解释为给出反应气体被液体表面吸收机制的分子水平图像。氨-硫酸体系与整个对流层中硫酸铵气溶胶的形成和生长有关，在污染的城市大气中尤为重要。该项目将把基于问题的学习纳入本科课程，并将赞助一个项目，奖励夏季研究实习，目的是增加妇女和未被充分代表的少数民族对科学研究的参与。对气溶胶的化学和物理性质的研究将使人们更好地了解它们在大气化学循环和气候中的作用。先前的液滴序列实验显示了表面介导反应的证据，而新的基于激光的光谱技术允许以直接的方式检查这些反应。参与这项研究和教育计划的学生将接触到有助于更好地了解污染的工作，以及基础研究在解决与社会相关的复杂化学问题中的作用。

Professor Heather Allen of Ohio State University has received a CAREER award from the Analytical and Surface Chemistry Program for sum frequency generation studies on gas-liquid surfaces, especially ones of environmental interest. Ammonia uptake by aqueous sulfuric acid solution surfaces will be investigated using broad-band SFG, allowing the acquisition of vibrational spectra specific to the surface region. The spectra will be interpreted to give molecular level pictures of the surface uptake mechanisms of the reactive gas by the liquid. The ammonia-sulfuric acid system has relevance to the formation and growth of ammonium sulfate aerosols throughout the troposphere and is particularly important in polluted urban atmospheres. The PI will incorporate problem-based-learning in undergraduate courses, and will sponsor a program that will award summer research internships with the goal of increasing the participation of women and underrepresented minorities in scientific research.Work on the chemical and physical properties of aerosols will lead to a better understanding of their role in atmospheric chemical cycles and in climate. Previous droplet-train experiments showed evidence for surface-mediated reactions, and new laser-based spectroscopies allow the examination of those reactions in a direct manner. Students involved in this research and education plan will be exposed to work that will lead to a better understanding of pollution, as well as the role of basic research in solving complex chemical problems relevant to society.