Time-dependent local density characteristics

The speed of p- and n-type doping and that of p-n junction formation depend on the ionic conductivity of the solid electrolyte. Because of the generally nonpolar characteristics of luminescent polymers like PPV, and the polar characteristics of solid electrolytes, the two components within the electroactive layer will phase separate. Thus, the speed of the electrochemical doping and the local densities of electrochemically generated p- and n-type carriers will depend on the diffusion of the counterions from the electrolyte into the luminescent semiconducting polymer. As a result, the response time and the characteristic performance of the LEC device will highly depend on the ionic conductivity of the solid electrolyte and the morphology and microstructure of the composite. 

Let us first consider, as extreme cases, the possibility that the molecular dynamics is controlled solely by (1) thermal energy fluctuations, or (2) local density fluctuations (i.e., free volume). Both cases are illustrated schematically in Figure 12 by plotting the isobaric and isothermal dependencies of the stractural relaxation times on volume. The characteristic feature of the isothermal dependence is the absence of any volume dependence of r indicating that the stmctural relaxation process is purely thermally activated. In the second case, the isobaric and isothermal curves superimpose into a master curve and such a behavior is consistent with free-volume approaches. A critical test of the origin of the different processes and of the relative influence of volume and temperature in each... 

The distance dependence of 1/r6 for the attractive potential is characteristic of the interaction between dipoles. This is because the attractive dispersion forces result from the mutual induction of electrostatic dipoles. Although a nonpolar molecule has no net dipole averaged over a period of time, at any one instant there will be dipoles due to the local fluctuations of electron density. Because the energies depend on the induction of a dipole, polarizability is an important factor in the strength of the interaction between any two atoms. 

The scope of a disaster can vary greatly and is partially dependent on the location of the disaster. A disaster in a rural community may not be considered a major event in an urban area because of the greater resource availability characteristic of urban areas. Conversely, an event that would have an impact in an urban setting may have next to no impact in rural areas because of low population densities. State, regional, and federal support does exist and will likely be made available in the event of a disaster (Richards, Burstein, Waeckerle, Hutson, 1999). However, because a required chain of notification must be completed to obtain outside support and because it takes time for state or federal officials to marshal the proper resources, disasters are usually local for the first days (Auf der Heide, 1989, 2006 Kaji Waeckerle, 2003), which was exemplified by the federal response to Hurricane Katrina. After the first few days, the extent of the support may be limited by the nature of the disaster. A widespread infectious epidemic may require that... 

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