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Capacitance, defined

Other interesting properties are the differential (C(1) and integral (CO capacitances, defined as... [Pg.21]

Since O varies with E, it is more convenient to introduce the differential capacitance defined by... [Pg.292]

Dielectric characterization involves the measurement of dipole responses to an applied electric field. The simplest measurement of the dielectric constant and dielectric loss involves the separation of two conductive plates. When a voltage (V) is applied to one plate, a charge is produced (Q) and induces an opposite charge on the other plate with the capacitance defined by the expression (Q = CV). When a dielectric material is placed between the plates, a polarization change will result and the capacitance of the system will increase relative to... [Pg.266]

Capacitors. Ceramic materials suitable for capacitor (charge storage) use are also dependent on the dielectric properties of the material. Frequently the goal of ceramic capacitors is to achieve maximum capacitance in minimum volume. The defining equation for capacitance is given by ... [Pg.342]

It should be ensured that under no condition of system disturbance w ould the filter circuit become capacitive when it approaches near resonance. To achieve this, the filter circuits may be tuned to a little less than the defined harmonic frequency. Doing so will make the L and hence Xl always higher than Xc, since... [Pg.745]

The influence of a particular dielectric on the capacitance of a condenser is conveniently assessed by the dielectric constant, also known as the relative permittivity or rarely specific inductive capacity. This is defined as the ratio of the relative condenser capacity, using the given material as a dielectric, to the capacity of the same condenser, without dielectric, in a vacuum (or for all practical intents and purposes, air). [Pg.112]

Power factor in an alternating current circuit is defined as the ratio of actual circuit power in watts (W) to the apparent power in voltage amperes (VA). The need for correction arises from fact that the majority of A.C. electrical loads take from the supply a lagging quadruple current (voltage amperes reactive, var) and thus operates at a lagging power factor due to the reactive (rather than capacitive) nature of their construction. [Pg.218]

The result can be simplified by making use of the above-defined pinch-off voltage [Eq. (14.54)1 and dielectric capacitance of the semiconducting layer. Further simplifications result from the assumptions that Cs 2> C, (Eq. (14.57)), and that the dopant and carrier concentrations arc equal (Eq. (14.58)). [Pg.253]

Metal/molten salt interfaces have been studied mainly by electrocapillary833-838 and differential capacitance839-841 methods. Sometimes the estance method has been used.842 Electrocapillary and impedance measurements in molten salts are complicated by nonideal polarizability of metals, as well as wetting of the glass capillary by liquid metals. The capacitance data for liquid and solid electrodes in contact with molten salt show a well-defined minimum in C,E curves and usually have a symmetrical parabolic form.8 10,839-841 Sometimes inflections or steps associated with adsorption processes arise, whose nature, however, is unclear.8,10 A minimum in the C,E curve lies at potentials close to the electrocapillary maximum, but some difference is observed, which is associated with errors in comparing reference electrode (usually Pb/2.5% PbCl2 + LiCl + KC1)840 potential values used in different studies.8,10 It should be noted that any comparison of experimental data in aqueous electrolytes and in molten salts is somewhat questionable. [Pg.147]

The discussion on the capacitive charging of conductive polymers continues 362 - 364) poiiowing Feldberg s hypothesis the capacitive charge should be proportional to the amount of oxidizable film whereby it is assumed that oxidation of the film occurs at one defined redox potential All available experimental findings are unequivocal evidence that the latter assumption is wrong. In a recent... [Pg.37]

The transition from isolated (Ho) to global (H) belongs to this class [see Eq. (6)], which is why capacitance under -control is defined as... [Pg.80]

We can define the principal electrical properties of polymers in terms of four characteristics electrical resistance, capacitive properties, dielectric strength, and arc resistance. We can change the surface characteristics of a polymer by subjecting it to a corona discharge generated by a strong electrical field. Lastly, we must also consider the influence of other physical properties on the application of polymers in electrical applications. [Pg.181]

The electric field or ionic term corresponds to an ideal parallel-plate capacitor, with potential drop g (ion) = qMd/4ire. Itincludes a contribution from the polarizability of the electrolyte, since the dielectric constant is included in the expression. The distance d between the layers of charge is often taken to be from the outer Helmholtz plane (distance of closest approach of ions in solution to the metal in the absence of specific adsorption) to the position of the image charge in the metal a model for the metal is required to define this position properly. The capacitance per unit area of the ideal capacitor is a constant, e/Aird, often written as Klon. The contribution to 1/C is 1 /Klon this term is much less important in the sum (larger capacitance) than the other two contributions.2... [Pg.14]


See other pages where Capacitance, defined is mentioned: [Pg.326]    [Pg.672]    [Pg.326]    [Pg.120]    [Pg.123]    [Pg.48]    [Pg.149]    [Pg.324]    [Pg.266]    [Pg.40]    [Pg.446]    [Pg.291]    [Pg.321]    [Pg.326]    [Pg.672]    [Pg.326]    [Pg.120]    [Pg.123]    [Pg.48]    [Pg.149]    [Pg.324]    [Pg.266]    [Pg.40]    [Pg.446]    [Pg.291]    [Pg.321]    [Pg.1943]    [Pg.2955]    [Pg.64]    [Pg.349]    [Pg.350]    [Pg.49]    [Pg.51]    [Pg.803]    [Pg.822]    [Pg.822]    [Pg.36]    [Pg.27]    [Pg.108]    [Pg.109]    [Pg.110]    [Pg.123]    [Pg.75]    [Pg.78]    [Pg.92]    [Pg.366]    [Pg.47]    [Pg.71]   
See also in sourсe #XX -- [ Pg.101 ]




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