Fractal-like aggregates
Diffusion limited model (random walk algorithm)
DLA 1.13: Modelling the morphology and TEM images of fractal aggregates of spherical particles
Description (in brief)
This windows-based software allows generating fractal aggregates of spherical particles. It uses a Diffusion Limited Aggregation (DLA) algorithm and the so-called fractal equation. The latter is respected, with a prescribed accuracy, at each aggregation step and for a given set of tunable parameters. The software outputs may be used for light scattering calculations, Transmission Electron Miroscopy (TEM) images analyses and validation of fractal analysis methods, or just to visualize fractal aggregates with 3D rendering software.
Main features of the software:
- Tunable parameters: fractal dimension, prefactor, radius of gyration, monomers' polydispersity and number, overlapping factor,...
- Serial calculations for selected parameters,
- Arbitrary rotations of the aggregates,
- Modeling of the corresponding TEM images,
- Export spheres coordinates as text files in POV-Ray, T-Matrix or DDScat software formats.
Terms of use
This software has been coded during Mariusz Wozniak's PhD thesis, supervised by myself and with the support of the ANR (CARMINA project), in the laboratory IUSTI (UMR 7343 CNRS/Aix-Marseille University, France). The code can be used without limitations in any not-for profit scientific research. We only request that in any publication using the outputs of this software a reference is given to the following publications of the authors of the software:
- Wozniak M., Onofri F.R.A., Barbosa S., Yon J., Mroczka J., Comparison of methods to derive morphological parameters of multi-fractal samples of particle aggregates from TEM images, Journal of Aerosol Science 47: 12–26 (2012) (pdf)
- Onofri F.R.A., M. Wozniak, S. Barbosa, On the Optical Characterization of Nanoparticle and their Aggregates in Plasma Systems, Contributions to Plasma Physics 51(2-3):228-236 (2011) (pdf)
Download:
- Short manual of the DLA/TEM software: DLA_Manual.pdf
- More information about the Diffusion Limited Aggregation algorithm : DLA_principle.pdf
- Software with all files (manual, principle, windows executable without installer, no virus): DLA.ver.1.13.02.zip
Additional information and usefull codes
- Additional information about this software can be found in Mariusz' PhD thesis
- Additional information about how to use this software to calibrate a method to measure the fractal dimension can be found in this paper : J. Mroczka, M. Wozniak, and F. R. A. Onofri, Algorithms and methods for the analysis of the optical structure factor of fractal aggregates, Metrology and Measurement Systems XIX, 459-470 (2012) (pdf)
- Link to PovRay software to generate 3D rendering views of fractal aggregates (we have developed some macros that will be available soon)
- Link to NASA Goddard Institute (T-Matrix Codes), Princeton (DDSCAT code) and Maxim Yurkin (ADDA code) web sites for computing electromagnetic scattering by aggregated particles.