Interstitial particle

Figure 6.1 The placement of ions in the face-centred or body-centred structures, and the location of interstitial particles on the [111] cell diagonal directions...

Thus, for a given particle loading, , the fine fraction in the bimodal assembly is a function of only the diameter ratio, dID a surprisingly simple result for an otherwise complex phenomenon. However, the inclusion of the liquid phase to the above particle assembly should modify the result somewhat. This can be seen very simply by expressing the interstitial particle population of the fines as a function of the continuous phase ... 

Diffusion of Interstitial Particles in a Chemical Concentration Gradient... 

A cloud water collector that separates unactivated (interstitial) particles from cloud droplets by jet impaction of these droplets on inert surfaces (12) provides a sample for chemical analyses. 

Figure 16. Concentrations of vacancies and interstitial particles in a positively doped Frenkel-disordered material taking account of association between cationic vacancies and dopant ions. The...

Clouds form when an air parcel is cooled sufficiently through vertical lifting that the water vapor in the parcel becomes supersaturated. Once water supersaturation is achieved, aerosol particles become activated to form cloud droplets (Chapter 15). The surface area of the growing drops provides an increasing sink for water vapor, causing the ambient supersaturation to reach a maximum and eventually decrease. Those particles that have been activated continue to grow those smaller than their critical sizes for activation shrink and become interstitial particles. 

The concentrations of charged atomic defects—point defects—follow the law of mass action. The considerations of thermodynamic equilibria can be applied to disorder equilibria in solid crystalline compounds, the so-called ordered mixtures. Point defects can be regarded as quasi-chemical species with which chemical reactions can be formulated. This has led to the so-called imperfection chemistry. As an example, the disorder equilibrium between vacancies and interstitial particles—the so-called Frenkel equilibrium—will be regarded. 

In this case a particle A moves from an A lattice site to an interstitial site whereby, for example, with respect to the unperturbed lattice a single positively charged interstitial particle Aj is formed, a vacancy Vi in the interstitial lattice is destroyed, and a negatively charged vacancy V on an A site is left. This exchange process can be written in the form of a chemical reaction, a so-called disorder reaction... 

The concentration of the interstitial particles or vacancies as building units is identical with the concentration as structure elements. 

For all crystals there exists at equilibrium a constant product of the concentrations of interstitial particles and the corresponding vacancies, the so-called Frenkel equilibrium which depends on temperature and pressure. 

The concentration of imperfection centers increases with rising temperature. The limiting case is crystals in which the concentrations of vacancies and interstitial particles become comparable there then occurs a statistical distribution of particles in normal lattice positions and in interstitial positions. In this case it is no longer reasonable to distinguish between regular and interstitial lattice positions. The total number of positions a single type of particle can occupy may be several times higher than the number of such particles in the crystal. 

V Core interstitial gas velocity Interstitial solids velocity Core interstitial particle velocity... 

Transportation of free or phagocytosed interstitial particles to the lymph nodes and... 

In the interstitial particle volume of the column, mass transfer is governed by both flow rate and coefficients of axial dispersion. The flow rate, u, is calculated by an expression. 

On the other hand, in a perfect material, reaction (1) cannot occur in the bulk of the material. This would imply the formation of K and X interstitial particles which are not supposed to exist. Such a reaction can only occur on the surfaces where a unit crystalline cell can be created or consumed. Thence the corresponding rate vi is nil V] = 0. (49)... 

The local environment of the interstitial particle is altered in a similar manner, as an excess proton distorts the local water structure (H30", H904). So it is structuraJly more precise to... 

On account of the conditions of equilibrium we find that the (electro-)chemical potential of Ag+, as an ionic component (not to be confused with a regular Ag+ structure element AgAg), is identical to the (electro )chemical potential of the interstitial particle (as building element) or, on account of Eq. (5.23), with the negative (electro-)chemical potential of the vacancy (as building element). This correspondence between the defects (Ag, Ag ) and the components (Ag ), which is frequently overlooked, clarifies many virtual problems encountered in the literature of defect chemistry (cf. Ref. [122]). On the basis of the analogy to electrons treated in the next chapter, (pAg+/Nm) may be referred to as the ionic Fermi level . All this will become much clearer in the later parts of the chapter. 

OEven without interaction ( free surface ), AkH is small for AgCl and AgBr (see temperature dependence of the intercept in Fig. 5.77). If the interstitial particle were the enriched carrier in the... 

Two mechanisms are of importance in the case of the migration of an interstitial particle (i) The defect (charge number Zj) jumps directly from one interstitial site to the next (Fig. 6.4b)... 

Adamson lYR, Prieditis H, Bowden DH. Instillation of chemotactic factor to silica-injected lungs lowers interstitial particle content and reduces pulmonary fibrosis. Am J Pathol 1992 141 319 326. 

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