Nanoparrticle Growth Mechanisms During New Particle Formation

在这个由国家科学基金会化学部环境化学科学项目资助的项目中，特拉华大学的默里·约翰斯顿教授正在研究纳米颗粒在大气中生长的化学机制。该项目将支持三名研究生的工作。这些学生将接受广泛的培训，并有能力在环境化学、工业分析化学、仪器仪表、纳米科学或学术界等领域从事职业生涯。社会将受益于培训能够预测人类活动变化如何影响气候的学生。约翰斯顿教授和研究生还将致力于提高特拉华大学本科生和普通公众的环境科学意识，将这项工作的概念和成果纳入正式的课程和公共宣传活动。生长足够快的纳米粒子可以达到作为种子形成云滴的大小。了解这些粒子是如何生长的，将有助于开发改进的模型来预测云的形成及其对气候的影响。目前的区域和全球大气模型在预测新粒子形成(NPF)期间碳质物质对纳米粒子生长速度的贡献方面能力有限。这一知识差距是确定NPF对当今气候和气候强迫(前工业化时代与现在的差异)的影响的最大不确定性。这项拟议工作的具体目标是阐明NPF过程中碳质物质生长纳米颗粒的化学机制。这项研究的结果将为发展和改进依赖于碳质物质对纳米颗粒生长的预测的模型提供基本的基础。

In this project funded by the Environmental Chemical Sciences program in the Division of Chemistry at the National Science Foundation, Professor Murray Johnston of the University of Delaware is studying the chemical mechanisms by which nanoparticles grow in the atmosphere. This project will support the work of three graduate students. These students will be broadly trained and capable of pursuing a career in areas such as environmental chemistry, industrial analytical chemistry, instrumentation, nanoscience, or academia. Society will benefit by training students who are able to predict how changes in human activity affects climate. Professor Johnston and graduate students will also work to increase awareness of environmental science among University of Delaware undergraduates and the general public, by incorporating the concepts and results of this work into formal coursework and public outreach events.Nanoparticles that grow fast enough, can reach a size where they serve as the seeds to form cloud droplets. Understanding how these particles grow will assist the development of improved models to predict cloud formation and its impact on climate. Current regional and global atmospheric models are limited in their ability to predict the contribution of carbonaceous matter to nanoparticle growth rates during new particle formation (NPF). This knowledge gap represents the greatest remaining uncertainty for determining the impact of NPF on today's climate and climate forcing (the difference between pre-industrial times and now). The specific objective of the proposed work is to elucidate chemical mechanisms of nanoparticle growth by carbonaceous matter during NPF. The results obtained from this research will provide a fundamental basis for developing and improving models that rely on the prediction of nanoparticle growth by carbonaceous matter.