Electric capacitance

Two models of surface hydrolysis reactions and four models of the electrical double layer have been discussed. In this section two examples will be discussed the diprotic surface group model with constant capacitance electric double layer model and the monoprotic surface group model with a Stern double layer model. More details on the derivation of equations used in this section are found elsewhere (3JL). ... 

In Chapter 2 it was shown that the Madelung field of a crystal is equivalent to a capacitive electric circuit which can be solved using a set of Kirchhoff equations. In Sections 3.1 and 3.2 it was shown that for unstrained structures the capacitances are all equal and that there is a simple relationship between the bond flux (or experimental bond valence) and the bond length. These ideas are brought together here in a summary of the three basic rules of the bond valence model, Rules 3.3, 3.4, and 3.5. 

K.L. Ostrowski, S.P. Luke, M.A. Benett, R.A. Williams, Application of capacitance electrical tomography for on-line and off-line analysis of flow pattern in horizontal pipeline of pneumaic conveyer, Chem. Eng. J. 77 (2000) 43-50. 

J. P. K. Seville, A. Ingram, X. Fan, and D. J. Parker, Positron Emission Imaging in Chemical Engineering Fei Wang, Qussai Marashdeh, Liang-Shih Fan, and Richard A. Williams, Electrical Capacitance, Electrical Resistance, and Positron Emission Tomography Techniques and Their Applications in Multi-Phase Flow Systems... 

Electrical Capacitance, Electrical Resistance, and Positron Emission Tomography Techniques and Their Applications in Multi-Phase Flow Systems... 

The bond flux can also be calculated by recognizing that in the ionic limit each bond is an electric capacitor (represented by flux linking two opposite charges). The network of atoms and bonds is thus a capacitive electrical circuit, and since in most equilibrium structures aU the bond capacitances are empirically found to be equal, the fluxes can be calculated using the Kirchhoff equations (2) and (3) in which the bond capacitances cancel. ... 

Motional capacitance Electrical (parallel) capacitance Dissipation, D = Q" ... 

Where 7 is the solution resistance, 7 p is the polarisation resistance and Cji is the double-layer capacitance. Various electrochemical phenomena at the metal solution interface causes a time lag and a measurable phase angle 9. These processes will be simulated by resistive and/or capacitive electrical networks. The impedance behaviour of an electrode may be expressed in Nyquis plot of Zj g (imaginary part of impedance) as a function of Z eai (real part of impedance) or in Bode plots of mod Impedance and 9 versus frequency, where co — 2 nf. 

The association of an inductor with a capacitor allows the two snbvarieties of electrodynamical energy, inductive (electromagnetic) and capacitive (electric or electrostatic), to be stored in the same system. The two system constitutive properties, inductance and capacitance, are the supports for the storage of energy and they link the state variables according to the following relations ... 

Name Electrical capacitance Electrical resistance Electrical inductance... 

The electric charge produced at the gauge poles under the dynamic action of a pressure is recorded in a suitable manner as a function of time. The usual manner is to lead the signal from the gauge poles first to the resistance electrical circuit and then to the resistance-capacitance electrical circuit. In the first circuit, the current strength (/) is registered ... 

Fig. 21 Room-temperature capacitance-frequency characteristics, a MIM and MIS structure devices (with applied a.c. voltage of 0.5 V). b,c Tan (8)-frequency characteristics (b) and quasi-static capacitance-electric field curves (c) for the MIS stractures (at 66 Hz) at different sweep/scan rate (dVoM/dt) as indicated. Larger hysteresis with slower scan rates ace found. (Reproduced with permission from Elsevier and [39])...

Fig. 6 The bond network shown in Fig. 5 can be represented as a capacitive electrical network...

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