scholarly journals Manufacturing and Processing Techniques Affecting Morphology of Pyrotechnic Oxidizer Particles

2001 ◽  
Vol 9 (4) ◽  
pp. 8-13
Author(s):  
Richard C. Dujay
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Potassium Nitrate ◽  
Forensic Identification ◽  
Current Investigation ◽  
Pyrotechnic Composition ◽  
Burn Rate ◽  
Processing Techniques ◽  
Individual Particles ◽  
Scanning Electron

In a pyrotechnic composition, the morphology (size, shape and surface features) of individual particles in the mixture influences both burn rate and the ease of ignition of the composition. Collectively, the larger, more rounded and smoother the particles, the lower the burn rate and the more difficult it is to ignite the composition. However, the purpose of the current investigation was only to catalogue some particle morphologies that may be useful in forensic identification of unconsumed or residual pyrotechnic evidence. In this study, potassium nitrate was chosen because of its common use in pyrotechnics and because of its similarity with other frequently used pyrotechnic oxidizers.All samples were prepared for scanning electron microscopy using a double-sided adhesive carbon disk applied to an aluminum post. Particles were mounted to the carbon disk and sputter coated with gold.

scholarly journals Clay-Based Brick Porosity Estimation Using Image Processing Techniques

2019 ◽  
Vol 29 (1) ◽  
pp. 1226-1234
Author(s):  
Safa Jida ◽  
Hassan Ouallal ◽  
Brahim Aksasse ◽  
Mohammed Ouanan ◽  
Mohamed El Amraoui ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Image Processing ◽  
Scanning Electron Microscopy ◽  
Computer Vision ◽  
Image Processing Techniques ◽  
Processing Techniques ◽  
Porosity Estimation ◽  
Microscopy Images ◽  
Scanning Electron

Abstract This work intends to apprehend and emphasize the contribution of image-processing techniques and computer vision in the treatment of clay-based material known in Meknes region. One of the various characteristics used to describe clay in a qualitative manner is porosity, as it is considered one of the properties that with “kill or cure” effectiveness. For this purpose, we use scanning electron microscopy images, as they are considered the most powerful tool for characterising the quality of the microscopic pore structure of porous materials. We present various existing methods of segmentation, as we are interested only in pore regions. The results show good matching between physical estimation and Voronoi diagram-based porosity estimation.

Cluster Analysis of Automated Fine-Particle Analysis Using Scanning Electron Microscopy

1997 ◽  
Vol 3 (S2) ◽  
pp. 1071-1072
Author(s):  
C.A. O’Keefe ◽  
J.P. Hurley
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cluster Analysis ◽  
Chemical Composition ◽  
Fine Particle ◽  
Submicron Particles ◽  
Particle Analysis ◽  
Solvent Ratio ◽  
Individual Particles ◽  
Scanning Electron

Because of analytical advances, submicron particles as small as 0.2 μm can be characterized for chemical composition, size, and shape using scanning electron microscopy (SEM). Once these characteristics are determined, cluster analysis can be used to group the individual particles into categories based on size, shape, and chemical composition.Submicron particle analysis is important when characterizing the ash to provide information to help solve ash-related problems in coal combustion and gasification systems. Since a combustion system has an excess of oxygen available, the resulting ash is typically easier to characterize than ash from a gasification system. In a gasification system, the lack of oxygen results in additional categories high in Cl and P.Adequate dispersion of submicron particles for proper analysis of individual particles is required because of the analysis volume of the SEM beam. Therefore, an aliquot of an aqueous solution with a set sample-to-solvent ratio is drawn while being sonicated. A few drops of solution are placed on a vitreous carbon substrate, allowing for particle dispersion on the surface of a smooth substrate. Next, the particles are analyzed by the fine-particle technique (FPT).

Material Testing of Natural Stones Used in Historical Buildings Based on Scanning Electron Microscopy and Nanoindentation

2013 ◽  
Vol 586 ◽  
pp. 186-189
Author(s):  
Petr Koudelka ◽  
Daniel Kytýř ◽  
Veronika Koudelková ◽  
Jaroslav Lukeš ◽  
Tomáš Doktor ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Historical Buildings ◽  
Heritage Preservation ◽  
Local Characteristics ◽  
Natural Stones ◽  
Processing Techniques ◽  
Signal Processing Techniques ◽  
Scanning Electron

In the case of material parameters required for evaluation of built heritage preservation state, knowledge of the least possible volume of removed sample is essential in order to minimize damage accumulation to the buildings. These requirements lead to determination of representative volume element (RVE) that was in this paper calculated using combination of image and signal processing techniques. Then, a detailed map of material properties was created using nanoindentation to evaluate local characteristics of the material. Furthermore, atomic composition of samples was quantified by energy dispersive spectrometry (EDX) detector for scanning electron microscopy (SEM) device. Presented method based on combination of SEM, EDX and nanoindentation techniques demonstrates possibility of effective testing in the field of historical buildings preservation.

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