FRACTAL THEORY APPLIED TO AEROSOL EXPERIMENTAL DATA
COLLECTED IN NORTH OF CHIHUAHUA CITY
Authors: Eduardo F. Herrera Peraza1, Balter Trujillo Navarrete1, Roman Pérez Balan,
Adrián Vázquez Gálvez2
1 Centro de Investigación en Materiales Avanzados S.C.; Departamento de Medio Ambiente y
Energía. Chihuahua. México. (CIMAV). eduardo.herrera@cimav.edu.mx. FAX: 614 439 1170
2 Comisión para la Cooperación Ambiental (CCA).
Modalidad: Oral, Contaminación Ambiental (Aire).
Keyword(s): Nanoparticles, MOUDI, Lacunarity, Hurts Coefficient
Introduction: Studies of multi-scaled atmospheric particles are based in different mechanisms
of nanoparticles growing. These mechanisms depend of many variables such as chemical
composition, gas phase concentration; meteorological variables etc. and have been the indirect
cause of different pulmonary diseases. Epidemiology studies have indicated an association
between the mortality and the incidence of decease due to the concentration mass of
atmospheric fine particles generated by the combustion. The area of surface of aerosol
particles, is the site that involves the interactions gas-particle, that increases to the toxicity of
the particles (Ku and Maynard 2005; Wentzel et al., 2003). Nevertheless, the chemical specific
mechanisms and/or physical, relating the effects of the health to the aerosol haven’t been
understood yet (Linak et al., 2007). The objective of the present paper is carry out the
measurements of Lacunarity and Hurts coefficients to establish the statistics dependences
among shape and contents of aerosols.
Methodology: For the understanding of these mechanisms it is necessary detailed studies of
the morphology and the chemical composition of particles (Wentzel et al., 2003; Filippov et al.,
2000). The morphology has been described by different methods based on the contour or
density of the particle, example of them is: form factors; chain codification; dimension fractal
and functions of contour example the transformation of Fourier and wave (Kindratenko et al.,
1997; Kindratenko et al., 1995; Kindratenko 2003). For the collection of the experimental data,
measurements of particles were obtained with MOUDI (Micro orifice Uniform Deposit Impactor)
(Marple et al. 1991), with particles cuts until 100 nm , collected in north of the City of Chihuahua
during the campaign of March and April of 2007 .
Results and Discussion: There isn’t sufficient information for the possible modifications of the
size variables and forms of the different particle, with respect to the environmental and
temporary conditions. The use of multivariate techniques sets out to know the structures
interdependence of the size, forms and atmosphere.
Conclusions: Results of the calculations of different form-factor parameters, Lacularity, and
Hurts coefficients were exposed in this work. Furthermore, the statistical dependences among
shape and contents of particulate matters were established.
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