Migration of species

The importance of track structure, the migration of species, the role of oxygen, the study of model compounds and the use of pulse radiolysis techniques are discussed. 

The physical meaning of the ambipolar conductivity relates to the correlated transport of several charge carriers, when an internal -> electrical field in the system impedes the migration of species with a higher - mobility, but enhances transfer of less mobile species. 

Rapra Technology Ltd has undertaken a detailed investigation into the migration of species from different types of adhesives used with laminated multi-layer materials (Barber et al, 2003). Migration of aromatic amines, BADGE, bisphenol A and polyols were examined. A description of the samples used and a brief summary of some of the results obtained from this analytical work are given below. 

Diffusion The migration of species from a region of high concentration in a solution to a more dilute region. 

Consider the migration of species A through a homogeneous region of space, like a small volume of tissue (Figure 3.3). General differential equations can be developed to describe the variation of concentration of compound A, Ca, with time and position in the tissue by first considering the conservation of mass within this small volume. 

The principle of operation of a multicompartmented electrodialysis unit (11) is shown in Fig. 1.11. The cation and anion permeable membranes carry a fixed charge thus they prevent the migration of species of like charge. In a commercial version of Fig. 1.11, there would be several hundred rather than three compartments, multicompartmentalization being required to achieve electric power economics, since electrochemical reactions take place at the electrodes. 

Surface migration of species and reaction taking place along the perimeter of islands of adsorbed species. 

Relatively unimpeded migration of species throughout the lattice may allow chemical functionalization of the rods subsequent to the construction of the framework. 

Migration of species from one electrode to the other the secondary reactions at the electrodes upon excessive charging or excessive discharging may lead to the formation of electrolyte-soluble species, which migrate from... 

To add another level of refinement and account for geographic migrations of species, RA Fisher in 1937 included a spatial dependence by introducing the diffusion equation. 

The first term of the right-hand side is Ohm s law for the migration of species n under the influence of an electrical field. The second term is Pick s first law for diffusion imder the... 

Easy observation of interaction and migration of species, provided Mjep,sii ... 

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