Dielectric dependence

Polarization which can be induced in nonconducting materials by means of an externally appHed electric field is one of the most important parameters in the theory of insulators, which are called dielectrics when their polarizabiUty is under consideration (1). Experimental investigations have shown that these materials can be divided into linear and nonlinear dielectrics in accordance with their behavior in a realizable range of the electric field. The electric polarization PI of linear dielectrics depends linearly on the electric field E, whereas that of nonlinear dielectrics is a nonlinear function of the electric field (2). The polarization values which can be measured in linear (normal) dielectrics upon appHcation of experimentally attainable electric fields are usually small. However, a certain group of nonlinear dielectrics exhibit polarization values which are several orders of magnitude larger than those observed in normal dielectrics (3). Consequentiy, a number of useful physical properties related to the polarization of the materials, such as elastic, thermal, optical, electromechanical, etc, are observed in these groups of nonlinear dielectrics (4). 

The Dielectric. Depending on the substrate, various dielectrics are used as diffusion and ion implantation masks, field and... 

To take into account the effect of wrapping on dielectric-dependent pairwise interactions and assess its role in defining cooperativity, we have adopted a semiem-pirical procedure to algorithmically keep track of the conformation-dependent microenvironments. Thus, the in-bulk potential energy contributions are regarded as zero-order terms, while cooperative effects arise due to the wrapping of favorable interactions brought about by hydrophobic third-body participation (cf. Fig. 3.2c). 

Ma, G., Sun, W., Tang, S.-H., Zhang, H., Shen, Z., Qian, S. Size and dielectric dependence of the third-order nonlinear optical response of Au nanocrystals embedded in matrices. Opt. Lett. 27, 1043-1045 (2002)... 

In contrast to dielectrics, only a few papers were concerned with femtosecond laser processing of polymers [18, 31, 32, 57-65]. In the present review, ablation of polymer films with a Ti sapphire laser system (150 fs, 800 nm) is discussed. The results are presented in the same order as in the previous chapter for the dielectrics dependence of modification threshold on bandgap, incubation phenomena, morphology after laser illumination. 

Power dissipation in a dielectric depends on both its dc conductivity and k". In general, a dielectric should be used at temperatures and frequencies that are as far removed as possible from a resonance or relaxation frequency. The composition should also be such as to minimize the dc conductivity. 

The mechanism of electrical conductivity in insulators, particularly polymers, is still under consideration, but it is established that the current resulting upon application of an electrical field across a dielectric (depending on its nature) is due to the following ... 

The spontaneous polarization of a dielectric depends strongly on T, this is the pyroelectric effect that we use for infrared (IR) detection (e.g., intruder alarms and thermal imaging). 

The behavior (Equation 15.7 and Equation 15.8) is in good agreement with indistinguishable experimental results for both dielectrics near the IMT and conductive phases at high and intermediate frequencies (0.01-0.1 eV) (Figure 15.6). Whether the lower frequency behavior is metallic or dielectric depends on the intergrain coupling. 

The capacitance of a dielectric depends on its dielectric constant, e, and thickness, d ... 

A dielectric dependence on the rate of reaction between Fe and FeOH in mixed alcohol-water solvents is explained by the dominance of electrostatic repulsion and an Fe-Fe distance of 7-8 A is estimated. In mixed pyridine/H20, reaction is between Fe(py) " and FeOH " The oxidation of U(IV) to U(VI) by Ce(IV) has been studied in (CH3)2CO. 

In an electroelastic boundary-value problem (BVP), the stress state at a point of die dielectric depends on the mechanical and the electrostatic variables. Similarly to die elastic problem, we can think of a trae stress o,y which is in equilibrium with the external (volume and surfece) mechanical forces that are appUed to the elastomer (Dorfinann and Ogden 2005 McMeeking and Landis 2005 Suo et al. 2008). This quantity is often referred to as the total (true) stress to which a total nominal stress can be associated employing again Eq. 1. The adjective total refers to the properties for which the two stresses eontain both mechanical and electrical information (often in a coupled way) at each point of the deformed elastomer, defined via constitutive equations. 

A dielectric is ideally an insulating material which, when introduced between two parallel plates of a capacitor, increases the capacitance of the system [2-3]. The capacitance of a capacitor completely filled with a dielectric depends on its geometry and the property of the dielectric material. For example, the capacitance of a parallel plate capacitor of surface area (m ) with a plate separation of L (m) is given by ... 

The extent of translucency and opacity for inherently transparent dielectric depends to a great degree on their internal reflectance and transmittance c arac e Many dielectric materials that are intrinsically transparent may be made trans even opaque because of interior reflection and refraction. A transmitted light earn is deflected in direetion and appears diffuse as a result of multiple scattering events. Opacity results when the seattering is so extensive that virtually none of the incident beam is transmitted imdefleeted to the back surface. 

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