Absolute Determination of Particle Size and Shape

1971 ◽  
Vol 232 (35) ◽  
pp. 192-193 ◽  
Author(s):  
D. C.-H. CHENG ◽  
H. M. SUTTON
Keyword(s):  
Particle Size ◽  
Absolute Determination ◽  
Size And Shape ◽  
Particle Size And Shape

Effect of Electron Microscope Magnification on the Determination of Particle Size and Shape by Image Analysis

2007 ◽  
Vol 121-123 ◽  
pp. 893-896
Author(s):  
Zheng Min Li
Keyword(s):  
Particle Size ◽  
Image Analysis ◽  
Standard Sample ◽  
Standard Specimen ◽  
Particle Diameter ◽  
Value Change ◽  
Size And Shape ◽  
Transmission Electron ◽  
Particle Size And Shape

To investigate the effect of magnification (M) on determination of particle size and shape by transmission electron microscopy (TEM) and image analysis. The calibration curve and its simulative equation of TEM magnification are obtained by measurement of a grating replica standard specimen at different magnifications. Based on the analysis of TEM images at a series of magnifications for a 350nm-sphere standard sample, It has been found that the two errors of its size measurement, caused by one pixel change of the pixel number per particle diameter (Np) and by one gray value change during thresholding, is smaller, and the shape of ‘circle’ particles are close to the standard one, while Np is larger than 35. It can be seen that the suitable TEM magnification is in inverse proportion to particle size and it can be calculated by given equation.

Modern Role of the Electron Microscope in Rubber Research

1961 ◽  
Vol 34 (2) ◽  
pp. 697-704 ◽  
Author(s):  
W. A. Ladd ◽  
M. W. Ladd
Keyword(s):  
Particle Size ◽  
Electron Microscope ◽  
Chain Structure ◽  
Main Role ◽  
Size And Shape ◽  
Carbon Gel ◽  
Electron Microscopes ◽  
Particle Size And Shape

Abstract Until recently, the main role of the electron microscope in rubber research was the determination of particle size and shape of reinforcing pigments and fillers. The electron microscope proved its value in its first industrial problem in 1940 when it showed the particle size of Micronex to be 28 mµ. In 1942 it established the correlation between particle size of carbon and rubber properties. The next contribution was the establishment of reticulate chain structure, in 1945, using stereo-photomicrography. The electron microscope led the way to the carbon gel concept when carbons producing different road wear results were shown to have equal particle size and structure. Micrographs of carbon gel were published in 1951. Studies of rubber latexes, various pigments and fillers were also applications of the electron microscope in which the determination of particle size and shape was involved. Today, improvements in resolution, development of new techniques and accessory equipment have greatly expanded the application of the electron microscope. This paper is concerned mainly with describing these new developments ; first, as a help to electron microscopists in the rubber field; second, to illustrate what can be done with the electron microscope, so that research and production men can recognize possible applications of this discerning tool to the solution of their problems. Electron microscopes have come a long way in the short 20-year period. Figure 1 shows the microscope used in our laboratories. This instrument is currently resolving detail as fine as 10 A or 1 mµ in routine daily operation. Its design makes possible the development of special holders and thereby increases its value as a research tool. Another piece of equipment that is as important in microscope research as the electron microscope itself is the evaporating unit shown in Figure 2. This is used for shadowing and forming replication films under vacuum, thus making possible studies of rubber surfaces and surfaces of pigments and other rubber ingredients. In shadowing, detail is made visible by coating the specimen with metal evaporated at an angle from the tungsten basket at A. Carbon can be evaporated by the arc at B, forming a replicating film or mold of the specimen. This will be discussed under “preparation”. Today, the proper preparation of specimens is the most important step in successful microscopy. The various preparations used are as follows.

Brake Wear Particle Size and Shape Analysis of Non-Asbestos Organic (NAO) and Semi Metallic Brake Pad

2014 ◽  
Vol 71 (2) ◽  
Author(s):  
Hussain, S. ◽  
M.K Abdul Hamid ◽  
A.R Mat Lazim ◽  
A.R. Abu Bakar
Keyword(s):  
Particle Size ◽  
Wear Particle ◽  
Brake Disc ◽  
Wear Particles ◽  
Brake Pad ◽  
Brake Pads ◽  
Size And Shape ◽  
Brake Wear Particles ◽  
Brake Wear ◽  
Particle Size And Shape

Brake wear particles resulting from friction between the brake pad and disc are common in brake system. In this work brake wear particles were analyzed based on the size and shape to investigate the effects of speed and load applied to the generation of brake wear particles. Scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDX) was used to identify the size, shape and element compositions of these particles. Two types of brake pads were studied which are non-asbestos organic and semi metallic brake pads. Results showed that the size and shape of the particles generatedvary significantly depending on the applied brake load, and less significantly on brake disc speed. The wear particle becomes bigger with increasing applied brake pressure. The wear particle size varies from 300 nm to 600 µm, and contained elements such as carbon, oxygen, magnesium, aluminum, sulfur and iron.

scholarly journals Particle Morphology Analysis of Biomass Material Based on Improved Image Processing Method

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Zhaolin Lu ◽  
Xiaojuan Hu ◽  
Yao Lu
Keyword(s):  
Image Processing ◽  
Particle Size ◽  
Particle Morphology ◽  
Processing Method ◽  
Image Resolution ◽  
Ultrasonic Dispersion ◽  
Image Processing Method ◽  
Size And Shape ◽  
Nominal Size ◽  
Particle Size And Shape

Particle morphology, including size and shape, is an important factor that significantly influences the physical and chemical properties of biomass material. Based on image processing technology, a method was developed to process sample images, measure particle dimensions, and analyse the particle size and shape distributions of knife-milled wheat straw, which had been preclassified into five nominal size groups using mechanical sieving approach. Considering the great variation of particle size from micrometer to millimeter, the powders greater than 250 μm were photographed by a flatbed scanner without zoom function, and the others were photographed using a scanning electron microscopy (SEM) with high-image resolution. Actual imaging tests confirmed the excellent effect of backscattered electron (BSE) imaging mode of SEM. Particle aggregation is an important factor that affects the recognition accuracy of the image processing method. In sample preparation, the singulated arrangement and ultrasonic dispersion methods were used to separate powders into particles that were larger and smaller than the nominal size of 250 μm. In addition, an image segmentation algorithm based on particle geometrical information was proposed to recognise the finer clustered powders. Experimental results demonstrated that the improved image processing method was suitable to analyse the particle size and shape distributions of ground biomass materials and solve the size inconsistencies in sieving analysis.

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