Metal-based reactive nanomaterials

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0014479700012126

Methods of Studying Root Systems . By W. Böhm. Berlin: Springer (1979), pp. 200, DM 69, $38.00.

Role of particulate matter from vehicle exhaust on porous building stones (limestone) sulfation

[1] The morphology of particles emitted by wildland fires contributes to their physical and chemical properties but is rarely determined. As part of a study at the USFS Fire Sciences Laboratory (FSL) investigating properties of particulate matter emitted by fires, we studied the size, morphology, and microstructure of particles emitted from the combustion of eight different wildland fuels (i.e., sagebrush, poplar wood, ponderosa pine wood, ponderosa pine needles, white pine needles, tundra cores, and two grasses) by scanning electron microscopy. Six of these fuels were dry, while two fuels, namely the tundra cores and one of the grasses, had high fuel moisture content. The particle images were analyzed for their density and textural fractal dimensions, their monomer and agglomerate number size distributions, and three different shape descriptors, namely aspect ratio, root form factor, and roundness. The particles were also probed with energy dispersive X-ray spectroscopy confirming their carbonaceous nature. The density fractal dimension of the agglomerates was determined using two different techniques, one taking into account the three-dimensional nature of the particles, yielding values between 1.67 and 1.83, the other taking into account only the two-dimensional orientation, yielding values between 1.68 and 1.74. The textural fractal dimension that describes the roughness of the boundary of the two-dimensional projection of the particle was between 1.10 and 1.19. The maximum length of agglomerates was proportional to a power a of their diameter and the proportionality constant and the three shape descriptors were parameterized as function of the exponent a.

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2005JD006659

Emissions from the laboratory combustion of wildland fuels: Particle morphology and size

Environmental monitoring in four European museums

IDAS : a Windows based software package for cluster analysis

~~ ~~ A method for the classification of individual aerosol particles into one of two main groups, namely, fly ash and soil dust, is presented. It is based on the calculation of the fractal dimensions of the images of the particles obtained with the computer-controlled scanning electron microscopy. The risk of an improper determination of the fractal dimension is pointed out. It is shown that spherically shaped particles that normally compose the majority of the fly ash particles do not possess fractality. The rarely met fly ash particles with very irregular shape possess two types of the fractal dimensions, namely, textural and structural. On the other hand, it is found that the soil dust particles have only a textural fractal dimension. The obtained results allow the unequivocal identification of the particle source, which is especially important when the chemical compositions of the particles are nearly the same.

Fractal dimensional classification of aerosol particles by computer-controlled scanning electron microscopy.

Hierarchical cluster analysis with stopping rules built on Akaike's information criterion for aerosol particle classification based on electron probe X-ray microanalysis

Morphological characterization of individual particle surfaces was explored by off-line image processing of data obtained by scanning electron microscope — microanalyzer. The fractal geometry was studied by two methods, the power spectrum and the variogram approach. Both methods were evaluated, theoretically by a series of numerically simulated surface profiles and experimentally on a set of pre-recorded secondary electron images of particle surfaces exposing characteristic textures. It was shown that the fractal approach could stand as a base of the methods enlarging the application of electron probe X-ray microanalyzers for individual particle characterization.

/pdf/quantitative-characterization-of-individual-particle-50j1k28q6k.pdf

Quantitative characterization of individual particle surfaces by fractal analysis of scanning electron microscope images

Elucidating the composition of atmospheric aerosols through the combined hierarchical, non-hierarchical and fuzzy clustering of large electron probe microanalysis data sets

B. Treiger

Papers

IDAS : a Windows based software package for cluster analysis

Fractal dimensional classification of aerosol particles by computer-controlled scanning electron microscopy.

Hierarchical cluster analysis with stopping rules built on Akaike's information criterion for aerosol particle classification based on electron probe X-ray microanalysis

Quantitative characterization of individual particle surfaces by fractal analysis of scanning electron microscope images

Elucidating the composition of atmospheric aerosols through the combined hierarchical, non-hierarchical and fuzzy clustering of large electron probe microanalysis data sets