Shape analysis, particulate material

Yamamoto H, Matsuyama T, Wada M. 2002. Shape distinction of particulate materials by laser diffraction powder analysis. Powder Technol. 122 205-211. 

This paper is a brief review of original basic engineering research in morphological analysis applied to particle characterization which has been conducted during the last 20 years at the University of Iowa, Center for Particulate Material Processing Sciences. The topics discussed include definitions, theory, instrumental and experimental aspects of size, shape and texture measurements of particulate material. 

Morphological analysis is concerned with particle characterization in the case of particle size, particle shape and particle texture. Particle texture may deal with the particle surface characteristics and also with the particle microstructure. Particle size and shape influence physical and chemical properties of particulate materials. Morphological analysis is being developed in order to facilitate a more accurate description of the properties and behavior of particulate systems from a fundamental knowledge of the characteristics of the particles of the system [1,2]. 

Here we address a problem which is commonly encountered in microscopy studies of particulate materials Given a collection of similar objects, such that the individual shapes occlude each other, how can the symmetry of these objects be extracted using methods of automated image analysis. The method we apply to solve the problem is to evaluate the symmetry of the occluded shapes, locate the center of symmetry, and reconstruct the symmetric shape most similar to the unoccluded original. 

Particle size analysis and measurement is an important operation in many industries. The stability, chemical reactivity, opacity, flowability, material strength, and some other properties of many materials are affected by the size distribution and characteristics of the particles within them. There are numerous techniques and instrumentation for all types of particle size analysis and characterization available. Some primary properties of particulate materials, mainly shape, will determine the way the particles are detected or... 

This basic classification is complemented by transportation methods because materials must be fed to or discharged from process steps and storage may be necessary before, between, and/or after processing. Particle size analysis quantitatively determines the distribution of particle sizes in the disperse system, a task of utmost importance since particle size, distribution, particle shape, and particle concentration decisively influence the behavior of a particulate system. 

EMS has the potential advantage of being applicable in highly concentrated suspensions, which opens the way for on-line applications (Carasso et al. 1995 Hunter 1998). It delivers reliable analysis data in many circumstances, in particular for solid particles with thin dilfuse layers and low polarisabilities. However, the interpretation of mobility spectra requires detailed knowledge of the particulate system, e.g. of particle shape and material properties (like dielectric constant) and sometimes of surface conductance. 

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