Electrical capacitance volume

Wang, F., Marashdeh, Q., Warsito, W., and Fan, L.-S., Imaging gas/solid jet penetration in a gas-solid fluidized bed using electrical capacitance volume tomography, AIChE Annual Meeting, Philadelphia, PA, USA, 16-21 November, Section 03B01 (2008). 

More recently, Wang et al. [212] proposed the electrical capacitance volume tomography (ECVT) to obtain instantaneous 3D images. 

Wang F, Marashdeh Q, Fan L-S, Warsito W (2010) Electrical Capacitance Volume Tomography Design and Applications. Sensors 10 1890-1917... 

A general method of estimating the temperature distribution in a body of any shape consists of replacing the heat flow problem by the analogous electrical situation and measuring the electrical potentials at various points. The heat capacity per unit volume C.,p is represented by an electrical capacitance, and the thermal conductivity k by an... 

Alshawabkeh and Acar [134] developed a theoretical model describing contaminant transport during electrokinetic remediation, based on the equilibrium chemistry of the solution and the electrochemical properties of the contaminants within the soil. The model demonstrates that the removal of ions from soils is caused by a combined effect of electrical, hydraulic, and concentration potential gradients that exist in the soil. The factors controlling the rate of change of these potential gradients included the volume compressibility and electrical capacitance of the soil, and the conductivities of the ions. 

Fig. 1 shows that the curves obtained with 0.5 and 5 mM K in the internal volume were displaced by only about 0.35 pH-units, or approx. 21 mV from one another. This is due to the effect of the membrane electrical capacitance on the distribution of at equilibrium [4,7]. We used the method of Apell and Bersch [ ] to calculate equilibrium values of the -diffusion potential after addition of proteoliposomes with a known internal -concentration to a medium with 50 mM K, in the presence of valinomycin. Fig. 2 shows the dependence of these diffusion potentials on the internal diameter of the proteoliposomes. The dashed line in Fig. 2 shows that with proteoliposomes of 27 nm internal diameter, the -diffusion potential obtained with an initial internal K -concentration of 0.5 mM is only 21 mV higher than the one obtained with an initial internal -concentration of 5 mM. The diffusion potential obtained in the latter case is 52 mV. These diffusion potentials correspond with ApH-values of 0.36 and 0.88 units, respectively. This is in good agreement with the results shown in Fig. 1, and the required internal diameter of 27 nm is in good agreement with electron-microscopic and other evidence on the size of the proteoliposomes [2]. Furthermore, Fig. 2 shows that vesicles of this diameter generate a K -diffusion potential of only 77 mV even if the initial internal -concentration is zero. Since ATP-synthesis was observed only above a threshold Apjj+ of 90 mV (Fig. 1), this explains why... 

A system may contain energy when it possesses the ability to store it, as already stated. This ability takes the form of two constitutive properties, one for each subvariety of energy inductance for the inductive subvariety, and capacitance for the capacitive one. These names are borrowed from electrodynamics and generalized to all energy varieties. So, there is a translational mechanical inductance (inertial mass), a rotational mechanical inductance (inertia), a hydrodynamical capacitance (compressibility integrated over the volume), a thermal capacitance (which depends on the specific heat), and so on. In electrodynamics, inductance and capacitance feature components called inductor (or self-inductance) and capacitor, respectively. Electric inductance relates current to the quantity of induction (induction flux) and electric capacitance relates potential to charge. 

Electrical capacitance techniques were also used to monitor the anisotropic liquid absorption in multidirections in a nonwoven fabric plane. The principle of the method is based on the fact that the dielectric constant of water is about 15—40 times higher than that of normal fibres and fabrics, and therefore, the capacitance of the transducers in a measuring system wdl be very sensitive to the amount of liquid absorbed by a fabric. The computer-integrated capacitance system is able to provide both dynamic (real-time) and multidirectional measurements of the wicking rate in terms of the volume of liquid absorbed. 

FRs of the functional domain are associated with the quahty assurance of the production system. For instance, the electrical capacitance of a layer is specified by an FR in the functional domain. The measurement of this electrical capacitance is performed during the quality assurance of the production system. Through product-specific setup of the SPC software component and appropriate actions, the electrical capacitance is kept within the limits during volume production. 

Volume in fluidics is equivalent to electrical charge, and mechanical elasticity of the walls of the channels (known as compliance deflned as change of volume due to change in pressure) is equivalent to electrical capacitance. More details on analogy related to channel with compliant wall will be discussed in a later section. Also the inertia of fluids has an eleetrical analog, namely, electrical inductance. 

Figure 2.12(a) shows an amount of gas trapped ahead of an advancing liquid front in a closed channel. The advancing liquid acts like a liquid piston. At atmospheric pressure, Pq the gas Alls the volume Vg. The volume V and pressure P of the gas change as the liquid advances. Similar to electrical capacitance, C = dq/dv q is the charge, v is the voltage applied), hydraulic capacitance known as compliance is defined as... 

Now an equivalent circuit, which takes into account both the ion transport along the TC and the charge transfer through the carbon electrode material to the current collector, may be represented as in Fig. 2, wherein N = a(c)/4r, Cm and Rm are the total NP capacitance and resistance in a unit electrode volume (defined here as a product of a unit electrode area and the tier thickness), Re is the electrical resistance of an electrode in the same unit... 

The electrical activity of a defect is characterized in part by its electrical level position, which can be determined by capacitance transient methods. When the capacitance transient spectra are monitored before and after exposure to atomic hydrogen, it is found in many systems that these levels disappear. This phenomenon has been associated with the formation of electrically inactive hydrogen-impurity complexes as summarized by Pear-ton et al. (1987) and in Chapter 5 of this volume. 

Volumetric Metering. This unit is employed where volumes exceeding the capacity of the automatic pipets are desired. Liquid flowing into the unit rises until it contacts a prepositioned probe. The contact probes are for electrically conducting liquids. Capacitance-sensitive probes are available for nonconducting or inflammable liquids. A number of liquids may be admitted in sequence by employing multiple probes and valves. 

From their calculations of the surface excess entropy and volume of the electric double layer at a mercury-aqueous electrolyte interface, Hill and Payne (HP) [147] postulated an increase in the number of water molecules in the Stern inner region as the surface charge a of about 30 piC/m2, which is consistent with the results of TC on a silver surface obtained some 30 years later. HP used an indirect method to determine the excess entropy and volume by measuring the dependence on temperature and pressure of the double layer capacitance at the mercury-solution interface. 

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