Low Fractal Dimension Cluster-Dilute Soot Aggregates from a Premixed Flame

作     者：Rajan K. Chakrabarty Hans Moosmüller W. Patrick Arnott Mark A. Garro Guoxun Tian Jay G. Slowik Eben S. Cross Jeong-Ho Han Paul Davidovits Timothy B. Onasch Douglas R. Worsnop 

作者机构：Desert Research Institute Nevada System of Higher Education Reno Nevada 89512 USA Chemical Physics Program University of Nevada Reno Nevada 89557 USA Department of Physics University of Nevada Reno Nevada 89557 USA Division of Engineering and Applied Sciences Harvard University Cambridge Massachusetts 02138 USA Department of Chemistry University of Toronto Toronto Ontario M5S 3H6 Canada Department of Chemistry Boston College Chestnut Hill Massachusetts 02467 USA Aerodyne Research Inc. Billerica Massachusetts 01821 USA 

出 版 物：《Physical Review Letters》 (Phys Rev Lett)

年 卷 期：2009年第102卷第23期

页      面：235504-235504页

核心收录：

学科分类：07[理学] 0702[理学-物理学] 

基　　金：U. S. DOE ASP [DE-FG02-05ER64008] National Science Foundation 

主　　题：Aggregates 

摘      要：Using a novel morphology segregation technique, we observed minority populations (≈3%) of submicron-sized, cluster-dilute fractal-like aggregates, formed in the soot-formation window (fuel-to-air equivalence ratio of 2.0–3.5) of a premixed flame, to have mass fractal dimensions between 1.2 and 1.51. Our observations disagree with previous observations of a universal mass fractal dimension of ≈1.8 for fractal-like aerosol aggregates formed in the dilute-limit via three-dimensional diffusion-limited cluster aggregation processes. A hypothesis is presented to explain this observation. Subject to verification of this hypothesis, it may be possible to control the fractal dimension and associated properties of aggregates in the cluster-dilute limit through application of a static electric field during the aggregation process.