Professor of Mechanical Engineering, Chemical Engineering, Macromolecular Science & Engineering, Biomedical Engineering, and Biophysics
Particulate emissions in the nanoparticle size range are related to two pressing environmental problems – the health impact of fine particles and global warming. The problems of both climate change and health effects point to the question of characterizing chemical and physical properties of atmospheric particles, which is obviously related to the relative role of natural and anthropogenic processes in their formation. Combustion is the main process through which man continuously injects particles into the atmosphere. More importantly, these particles are produced at the smallest sizes physically possible in the form of clusters with nanometric dimensions. Therefore, it is clear that it is not possible to give a precise answer to the environmental problems outlined above, without going deeper into the chemistry and physics of the formation of particles at high temperature during combustion processes, and following their subsequent evolution and fate at ambient temperature.
The theoretical nano-science we are developing involves a novel multiscale computer simulation approach to study the formation and fate of carbonaceous material. The use of multiscale methods, such as the Kinetic Monte Carlo technique combined with Molecular Dynamics, can make it possible to follow the transformations that occur during nanoparticle formation in a chemically specific way, providing information on both the chemical structure and the configuration of the nanoparticles and young soot particles. This approach provides a connection between the various time scales in the nanoparticle growth and self-assembly problem, together with an unprecedented opportunity for the understanding of the atomistic interactions underlying nanoparticle structures and growth.
The Violi research group is developing computational methodologies to bridge the length and time scales in the important area of nanocluster self-assembly via coarse-graining techniques. This powerful new approach will not only have a large impact for understanding combustion-generated carbon nanoparticles, but also in the general area of nanoparticle self-assembly.
In short, there is a lifetime of remarkably interesting research to be done in this area, and we are pushing forward this frontier with powerful computer modeling approaches.
University of Michigan
Mechanical Engineering and Chemical Engineering Departments
Ann Arbor, Michigan
Associate Professor, 2009-present
Assistant Professor, 2006-2009
University of Utah
Department of Chemistry
Salt Lake City, Utah
Research Assistant Professor, 2004-2005
Research Associate 1/2002 – 12/2005
Post-doctoral Research Assistant, 1999-2001
Bernard Lewis Fellowship, for “High Quality Research in Combustion,” International Combustion Institute, Edinburgh, Scotland, 2000
John Zink Award, Salt Lake City, Utah, 2000
Enichem Prize for Distinguished Thesis, 1994
Erasmus Fellowship at the Department of Chemical and Biochemical Engineering at the University College of London, England, 1992-92
Enichem Award of Merit for Best Curriculum Studiorum, Naples, Italy, 1991
S. Izvekov, A. Violi “A Coarse-Grained Molecular Dynamics Study of Carbon Nanoparticle Aggregation”, J. Chem. Theory Comput. 2(3), 504-512 (2006).
R. Chang, A. Violi “Insights into the effect of combustion-generated carbon nanoparticles on biological membranes: a computer simulation” Journal of Physical Chemistry B, 110(10). 5073-5083 (2006).
D. Wang, A. Violi, D.H. Kim, J.A. Mullholland “Formation of Naphthalene, Indene and Benzene from Cyclopentadiene Pyrolysis: A DFT Study” Journal of Physical Chemistry A, 110(14), 4719-4725 (2006).
S. Izvekov, A. Violi “Systematic Coarse-Graining of Nanoparticle Interactions in Molecular Dynamics Simulation” Journal of Physical Chemistry B 109(36): 17019-17024 (2005).
A. Violi, G.A. Voth “A multi-scale computational approach for nanoparticle growth in combustion environments” High Performance Computing and Communications, Proceedings Lecture Notes in Computer Science 3726: 938-947 (2005).
A. Violi “Cyclodehydrogenation Reactions to Cyclopentafused Polycyclic Aromatic Hydrocarbons” Journal of Physical Chemistry A 109(34): 7781-7787 (2005).
A. Violi, G.A. Voth, A.F. Sarofim “The relative roles of acetylene and aromatic precursors during soot particle inception” Proc. Combust. Inst. 30: 1343-1351 (2005).
Cooke J.A., Bellucci M., Smooke M.D., Gomez A., Violi A., Faravelli T., Ranzi E. “Computational and Experimental Study of JP-8, a Surrogate, and its Components in Counterflow Diffusion Flames” Proc. Combust. Inst. 30: 2343-2351 (2005).
A. D’Anna A. Violi “Detailed Modeling of the Molecular Growth Process in Aromatic and Aliphatic Premixed Flames” Energy & Fuels 19(1): 79-86 (2005).
A complete list of publications can be found at the Violi Research Group.