Interaction between particles overview

The purpose of this chapter is to provide an overview of the science related to interaetions of particles with the respiratory traet, thereby providing an introduction to the ehapters that follow. I have purposefully used the term respiratory tract, rather than lung to describe the scope of this chapter. The respiratory tract includes the structures from the nares, or nose, to the respiratoiy bronchioles and alveoli, in which gas exchange occurs. The term lungs is used both in a more restrieted sense to include only the bronchioles and alveoli and, broadly, to include all of the respiratory tract. The study of interactions between particles and the respiratory tract is extraordinarily rich from a scientific viewpoint and also of immense importance because it relates directly to major societal issues. 

Burnett PGG, Daughney CJ, Peak D (2006) Cd adsorption onto Anoxybacillus flavithermus Surface complexation modeling and spectroscopic investigations. Geochim Cosmochim Acta 70 5253-5269 Chenu C, Stotzky G (2002) Interactions between microorganisms and soil particles an overview. In Huang PM, Bollag J-M, Senesi N (eds) Interactions... 

An overview of the origins of yield stress and parameters which can lead to variations in behaviour with highly filled polymer dispersions is given by Malkin [1]. Much of the following literature, describing experimental work undertaken, demonstrates that yield phenomena can be correlated with the extent of interaction between the filler particles and the formation of a network structure. However, the actual behaviour observed during experimentation may also depend on the deformation history of the material, or the time and temperature of imposed deformation, especially if the material exhibits thixotropic properties. 

In order to control protein adsorption, to enhance it in some cases and prevent it in others, it is necessary to understand the various stages involved in the process. The interaction of protein molecules with polystyrene (PS) latex particles having a well-defined surface has proved to be a very useful model system with which to study the interfacial behavior of proteins. Other colloidal systems, including silica and metal particles, have also been used in these investigations, and although this review concentrates mainly on interactions between proteins and latex particles, other systems are also mentioned where appropriate. Before looking at the interactions of proteins with PS latex particles in detail, it is worthwhile to take a brief overview of the two major components in the system. 

This section presents a general overview on the mode of action of dispersants in refractory castables, focusing especially on the ability of these molecules to adsorb and modify the surface chemistry of particles (Parts A—C), the secondary effects that may arise from the addition of dispersants to the castable matrix (Part D), the possible interactions between dispersants and cement particles (Part E), and novel routes that have been applied to design the dispersant molecule in order to optimize the rheological behavior of castables and concretes (Part F). 

In this chapter, the theories as well as the experimental justification for the mechanism of stabilization and destabilization of colloidal dispersions are outlined. Interacting forces between colloidal particles are analyzed and an overview of experimental methods for assessing the dispersion and relevant properties is given. The stabilization and flocculation of dispersions in the presence of surfactants and polymers is discussed in the last two sections. 

TABLE 3.1 Overview of Possible Interaction Forces Between Atoms, Molecules, and Particles... 

Total internal reflection microscopy (TIRM) was introduced in 1987 by Prieve et al. [343]. TIRM allows to probe the interaction of a single microsphere with a transparent flat plate. In a TIRM experiment, a microsphere is allowed to sediment toward the plate. The technique relies on repulsive forces between sphere and plate. This repulsion will typically result from electric double layer or steric forces. They keep the sphere from getting into contact with the plate. Thermal fluctuations will constantly change the precise distance. The distance between sphere and plate is monitored by the light intensity scattered from the particle when illuminated by an evanescent wave and can be determined with a resolution of w 1 nm. By recording the fluctuations in vertical position of the sphere due to Brownian motion, the potential energy of interaction and the diffusion coefficient of the sphere can be deduced. For overviews of the technique, see Refs [344, 345]. 

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