Related Experiment Video
Updated: May 21, 2026
07:47
Experimental Protocol to Investigate Particle Aerosolization of a Product Under Abrasion and Under Environmental Weathering
Published on: September 16, 2016
Deposition of general ellipsoidal particles
1Center for Theoretical and Computational Physics, University of Lisbon, Avenida Professor Gama Pinto 2, 1649-003 Lisboa, Portugal. reza@cii.fc.ul.pt
Summary
Particle shape significantly impacts granular deposit density and anisotropy, while size variations play a minor role. Nonsymmetrical ellipsoids yield maximum density, and non-spherical shapes enhance vertical contact forces.
Area of Science:
- Physics
- Materials Science
- Geophysics
Background:
- Granular deposits exhibit complex macroscopic properties influenced by particle characteristics.
- Understanding these properties is crucial for applications in porous media and sedimentation.
Purpose of the Study:
- To systematically investigate the density and anisotropy of granular deposits formed by ellipsoidal particles.
- To analyze the influence of particle shape and size polydispersity on deposit properties.
Main Methods:
- Utilized molecular dynamics simulations to construct granular deposits.
- Efficiently and accurately computed contact forces between ellipsoidal particles.
Main Results:
- Particle shape significantly affects macroscopic deposit properties; size polydispersity has a secondary role.
- Maximum deposit density observed for specific nonsymmetrical ellipsoids, exceeding that of prolate or oblate shapes.
- Increasing deviation from spherical shape leads to preferred contact forces along the vertical direction.
Conclusions:
- Particle shape is a dominant factor in granular deposit characteristics.
- Findings offer insights for developing accurate porous media models and understanding sedimentation dynamics.
Related Concept Videos
01:09Colloidal precipitates
The high insolubility of some precipitates can result in an unfavorable relative supersaturation. This can lead to colloidal particles with a large surface-to-mass ratio, where adsorption is promoted. For instance, in the precipitation of silver chloride, silver ions are adsorbed on the surface of the colloidal particles, forming a primary layer. This layer attracts ions of opposite charge (such as nitrate ions), forming a diffuse secondary layer of adsorbed ions. This electric double layer...
01:29The Colloidal State
The formation of a colloidal system is exemplified by an aqueous solution containing Cl− ions is introduced to another containing Ag+ ions, resulting in the precipitation of solid AgCl as extremely tiny crystals. Instead of settling out as a filterable precipitate, these crystals remain suspended in the liquid, showcasing a colloidal system.A colloidal system involves colloidal particles within the approximate range of 1 to 1000 nm in at least one dimension, dispersed in a medium called the...
01:16Precipitate Formation and Particle Size Control
In precipitation gravimetry, the precipitating agent should react specifically or selectively with the analyte. While a specific reagent reacts with the analyte alone, a selective reagent can react with a limited number of chemical species.
The obtained precipitate should be either a pure substance of known composition or easily converted to one by a simple process, such as ignition or drying. In addition, the precipitate should be insoluble and easily filterable. In general, filterability...
The obtained precipitate should be either a pure substance of known composition or easily converted to one by a simple process, such as ignition or drying. In addition, the precipitate should be insoluble and easily filterable. In general, filterability...
01:17Colloids and Suspensions
Children at play often make suspensions such as mixtures of mud and water, flour and water, or a suspension of solid pigments in water known as tempera paint. These suspensions are heterogeneous mixtures composed of relatively large particles visible to the naked eye or seen with a magnifying glass. They are cloudy, and the suspended particles settle out after mixing. The suspended particles in a suspension settle out after some time of mixing. The separation of particles from a suspension is...
01:08Electrodeposition
Electrodeposition is a technique used to separate an analyte from interferents by electrochemical processes. Here, the analyte is a metal ion that can be deposited on an electrode immersed in the sample solution. The electrochemical setup consists of an anode and a cathode. When an electric current is applied to the setup, oxidation occurs at the anode. At the cathode, which consists of a large metal surface, metal ions undergo reduction and deposit onto the surface.
Electrodeposition can...
Electrodeposition can...
01:30Ellipses
An ellipse is formed when a right circular cone is intersected by an inclined plane that does not cut through its base. This intersection yields a closed, symmetric curve characterized by distinctive geometric properties. Most notably, an ellipse is defined as the collection of all points in a plane for which the combined distances to two fixed points—called the foci—remain constant.The ellipse features two principal axes: the major and the minor axes. The major axis is the longest diameter,...