scholarly journals Characterization and analysis of the aspect ratio of carbide grains in WC–Co composites

RSC Advances ◽  
2018 ◽  
Vol 8 (60) ◽  
pp. 34468-34475 ◽  
Author(s):  
Xiaokun Yuan ◽  
Yuan Ji
Keyword(s):  
Aspect Ratio ◽  
Grain Shape ◽  
Parameter Analysis ◽  
Ratio Distribution ◽  
Novel Approaches ◽  
Aspect Ratio Distribution

To study the aspect ratio distribution of carbide grains in WC–Co composites, two novel approaches, namely grain shape ellipse calculation and five parameter analysis (FPA) methods, are reported in this work.

Aspect Ratio Analysis Using Image Processing for Rice Grain Quality

2010 ◽  
Vol 6 (5) ◽  
Author(s):  
Amit K Aggarwal ◽  
Ratan Mohan
Keyword(s):  
Image Processing ◽  
Aspect Ratio ◽  
Local Market ◽  
Rice Grain ◽  
Ratio Analysis ◽  
Ratio Distribution ◽  
Aspect Ratios ◽  
Percent Accuracy ◽  
Aspect Ratio Distribution

Determination of aspect ratio distribution is important for elongated, needle-shaped particles whose utility and/or value may depend on this feature. In this work rice grain is taken as an example of such a particle and its aspect ratio distribution in various samples is found using image processing. The samples examined were from three different grades (commonly termed as full, half and broken) sold in local market and priced according to their size. From the analysis, reference aspect ratios were assigned to classify the grains and hence determine the extent of off-size in each market grade. Further, the effectiveness of the technique to quantify mixed or adulterated grades was studied. It was found that it is possible to know the undesired content within 10 percent accuracy.

scholarly journals A General Method for Estimating Bulk 2D Projections of Ice Particle Shape: Theory and Applications

2019 ◽  
Vol 76 (1) ◽  
pp. 305-332 ◽  
Author(s):  
Edwin L. Dunnavan ◽  
Zhiyuan Jiang
Keyword(s):  
Aspect Ratio ◽  
Particle Shape ◽  
Ratio Distribution ◽  
Aspect Ratios ◽  
Shape Uncertainty ◽  
Aspect Ratio Distribution ◽  
Spheroidal Geometry ◽  
Orientation Parameters ◽  
General Method

Abstract The orientation of falling ice particles directly influences estimates of microphysical and radiative bulk quantities as well as in situ retrievals of size, shape, and mass. However, retrieval efforts and bulk calculations often incorporate very basic orientations or ignore these effects altogether. To address this deficiency, this study develops a general method for projecting bulk distributions of particle shape for arbitrary orientations. The Amoroso distribution provides the most general bulk aspect ratio distribution for gamma-distributed particle axis lengths. The parameters that govern the behavior of this aspect ratio distribution depend on the assumed relationship between mass, maximum dimension, and aspect ratio. Individual spheroidal geometry allows for eccentricity quantities to linearly map onto ellipse analogs, whereas aspect ratio quantities map nonlinearly. For particles viewed from their side, this analytic distinction leads to substantially larger errors in projected aspect ratio than for projected eccentricity. Distribution transformations using these mapping equations and numerical integration of projection kernels show that both truncation of size distributions and changes in Gaussian dispersion can alter the modality and shape of projection distributions. As a result, the projection process can more than triple the relative entropy between the spheroidal and projection distributions for commonly assumed model and orientation parameters. This shape uncertainty is maximized for distributions of highly eccentric particles and for particles like aggregates that are thought to fall with large canting-angle deviations. As a result, the methods used to report projected aspect ratios and the corresponding values should be questioned.

scholarly journals Estimation of Aspect Ratio of Cellulose Nanocrystals by Viscosity Measurement: Influence of Aspect Ratio Distribution and Ionic Strength

Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 781 ◽  
Author(s):  
Qiang Wu ◽  
Xiuwen Li ◽  
Qian Li ◽  
Siqun Wang ◽  
Yan Luo
Keyword(s):  
Ionic Strength ◽  
Aspect Ratio ◽  
Acid Hydrolysis ◽  
Bacterial Cellulose ◽  
Cellulose Nanocrystals ◽  
Viscosity Measurement ◽  
Viscous Effect ◽  
Ratio Distribution ◽  
Hückel Theory ◽  
Aspect Ratio Distribution

The influence of the cellulose nanocrystal (CNC) aspect ratio (L/d) distribution and ionic strength of different salts on the L/d estimation by viscosity measurement were investigated. The L/d distribution was controlled by mixing two CNC, with different L/d, which were prepared by acid hydrolysis from wood and bacterial cellulose. The results demonstrated that the L/d distribution did not affect the accuracy of the CNC L/d estimated by viscosity measurements using the Batchelor equation, and the calculated L/d was the number-average L/d. Moreover, monovalent (NaCl), divalent (CaCl2), and trivalent (AlCl3) salts were chosen to study the influence of ionic strength on the CNC L/d estimation by viscosity measurement. It was found that NaCl and CaCl2 could be added to the CNC suspension to screen the electro-viscous effect and estimate the actual physical CNC L/d by viscosity measurement, and the content of NaCl and CaCl2 can be predicted by the Debye–Hückel theory. However, a small amount of AlCl3 induced CNC aggregation and increased intrinsic viscosity and predicted L/d.

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