Fundamental Forces in Particle Adhesion

Natural sources and experimental generation of bioaerosols: Challenges and perspectives

“…Thus, storage can affect the flowability of the material within feeding mechanisms and break-up during aerosolization (Gό rny et al 2002;Masuda 2009). Irrespective of storage conditions, particles <10 mm have high attractive forces between particles and to surfaces that must be overcome for efficient dispersal (Beaudoin et al 2015), and these effects are highly sensitive to humidity (Inizan 2018). Preparation method can affect the size of the dried particles, for example, milling parameters influenced the final size of Bacillus thuringiensis particles used as a biopesticide (Kim and Je 2012).…”

An enhanced centrifuge-based approach to powder characterization: Experimental and theoretical determination of a size-dependent effective Hamaker constant distribution

“…In order to determine an effective Hamaker constant distribution, the van der Waals adhesion force of model spherical particles against a flat substrate [38] was calculated using the well-established approximate relationship:…”

Microsphere Handling at the Microscale: New Tools and New Effects

“…[26] To remedy this, and instead of using a pairwise additive approach, Lifshitz predicts the van der Waals interactions based on quantum electrodynamics by treating the bodies as a continuum and including a third intervening non-vacuum medium. [13] This approach is convenient since we measure the forces at a continuum level. The Hamaker constant for material i interacting with material j across medium k, can be estimated using: [26;87] A ikj ≈ A iki A jkj (2.5) where A iki denotes the Hamaker constant of material i interacting with itself 12 2.…”

“…The relative humidity of air can therefore significantly affect the particle-particle and particle-wall interactions, and thus the capillary force should be taken into account for particulate systems. [13] Two equations are fundamentally important to understand the capillary force.…”

“…[185;248] A caveat here is that Coulomb interaction could become stronger provided that particles can respond to an electric field or opposite charge of opposing surfaces. [13] Figure 2.2: An empirically established triboelectric series that shows an ordering of materials based on direction of charge transfer. A material closer to the top of the series contacted with a material closer to the bottom will charge positively (while the other material charges negatively).…”