CAREER: Formation, Growth, and Phase State of Organic Nanoaerosols in Indoor Environments

尽管来自汽车、工厂和其他户外来源的空气污染被公众公认为潜在的健康风险，但美国人90%的时间都在室内度过。因此，改善家庭和办公室的空气质量至关重要。人类暴露于空气污染中的颗粒物会对健康产生不利影响。一种重要的室内颗粒是纳米气溶胶--尺寸小于100纳米的颗粒。需要新的研究来更好地了解纳米气溶胶在建筑物中的命运和运输，以更好地预测人类暴露。该职业发展计划的目标是阐明控制室内纳米气溶胶动力学的基本机制，并激励新一代工程师解决新兴的室内空气质量（IAQ）挑战。这项研究将为改善室内空气质量和促进人类健康提供基础。拟议的研究旨在了解室内环境中有机纳米气溶胶（nOA）的复杂形成，生长和转化。具体的研究目标是：1）使用最先进的气溶胶仪器研究nOA的形成机制，直至分子长度尺度; 2）探索nOA凝聚和凝聚生长动力学; 3）发现室内nOA源类型、相对湿度、温度和分子组成如何影响尺寸分辨的nOA相态; 4）阐明nOA相态对吸湿生长/收缩和过滤动力学的作用;以及5）通过在普渡大学ReNEWW House（Retrofit Net-zero：Energy，Water，and Waste）和Herrick Living Lab办公室的实地活动来表征被占用环境中的nOA动力学。这项研究将改变我们在纳米水平上观察nOA成核事件的能力，从而确定nOA的形成，生长和相态如何随不同的室内nOA源而变化。将产生关于nOA转化如何影响供暖、通风和空调（HVAC）过滤器上沉积的新知识。这项研究将利用全尺寸的建筑测试系统，以了解nOA运输，转换和暴露在现实的建筑操作。一个教育框架将被开发，这将激励新一代的土木和环境工程专业的学生解决室内空气质量面临的挑战美国和全球社会。通过服务，体验和团队学习的结合，这个职业教育计划将以整体的方式吸引和激发普渡大学的本科生和研究生。在肯尼亚的国际室内空气质量项目和在ReNEWW House的推广活动将为向公众展示nOA研究提供一个平台。该奖项反映了NSF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。

Although air pollution from automobiles, factories, and other outdoor sources is well-recognized as a potential health risk by the public, Americans spend 90% of their time indoors. It is thus essential to improve the quality of air in homes and offices. Human exposure to particles in air pollution is responsible for adverse health effects. An important class of indoor particles are nanoaerosols - particles smaller than 100 nanometers in size. New research is needed to better understand the fate and transport of nanoaerosols in buildings to better predict human exposure. The goals of this CAREER development plan are to elucidate the fundamental mechanisms governing the dynamics of indoor nanoaerosols and to inspire a new generation of engineers to solve emerging indoor air quality (IAQ) challenges. This research will provide a foundation to transform our ability to improve IAQ and promote human health. The proposed research seeks to understand the complex formation, growth, and transformation of organic nanoaerosols (nOA) in indoor environments. The specific research objectives are to: 1) investigate nOA formation mechanisms down to molecular length scales using state-of-the-art aerosol instrumentation; 2) explore nOA coagulation and condensational growth dynamics; 3) discover how size-resolved nOA phase state is influenced by indoor nOA source type, relative humidity, temperature, and molecular composition; 4) elucidate the role of nOA phase state on hygroscopic growth/shrinkage and filtration kinetics; and 5) characterize nOA dynamics in occupied environments through field campaigns at the Purdue ReNEWW House (Retrofit Net-zero: Energy, Water, and Waste) and Herrick Living Lab offices. This research will transform our ability to observe nOA nucleation events at the nanometer level, thereby establishing how nOA formation, growth, and phase state vary with different indoor nOA sources. New knowledge on how nOA transformations influence deposition on heating, ventilation, and air conditioning (HVAC) filters will be produced. This research will utilize full-scale building test systems to understand nOA transport, transformation, and exposure under realistic building operations. An educational framework will be developed that will inspire a new and diverse generation of civil and environmental engineering students to solve IAQ challenges facing the U.S. and global community. Through a combination of service, experiential, and team-based learning, this CAREER education plan will engage and excite undergraduate and graduate students at Purdue University in a holistic way. International IAQ projects in Kenya and outreach events at the ReNEWW House will offer a platform for demonstrations of the nOA research to the general public.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.