Current electrical analogue

Inductance can be thought of as an electrical analogue to inertia, so cuirent flow is opposed at short times. Strictly speaking, a potential V is induced in the circuit immediately after the circuit is switched on, with V of the opposite polarity to that being applied. The current caused by the application of V tries to stop the net flow of current. 

In the electrical analogue the thermal conductance, heat flow and temperature are equivalent to the electrical conductance, current and voltage respectively. 

Dielectric measurements are the electrical analogue of dynamic mechanical measurements. The mechanical stress is replaced by an alternating voltage across the sample (a.c. field) and the alternating strain becomes the stored charge (0 in the simple capacitor. This is always measured as its derivative dQ/dr = a.c. current. Samples are typically thin sheets, films or liquids, which can be clamped between parallel-plate electrodes as shown for the PL-DETA, as shown in Figure 7.29. The dielectric data are obtained from phase and amplitude measurements of current and voltage to resolve the components of ... 

Based on Kirchhoff s current law and voltage law, a discrete time mathematical description of the electrical analogue battery model is derived as state update Eq. (1) and output Eq. (2). 

Photodiodes are the modem analogues to photocells. They increase their electrical resistance under light impact which, as part of an electric circuit, can be measured easily. Many current instruments display diode arrays instead of a single diode. Tens of photodiodes are arranged in a tight area. They are exposed to the sample bound spectrum where they respond to the color that corresponds to their positions in the diode array. A rapid, periodically performed electrical interrogation of all diodes (sequence periodicity in the order of milliseconds) reveals a quasi-stationary stable spectrogram. More sophisticated than photodiodes are phototransistors. They amplify internally the photoelectric effect, but the sensitivity of a photomultiplier cannot be achieved. 

The previous chapters dealt with ISE systems at zero current, i.e. at equilibrium or steady-state. The properties of the interface between two immiscible electrolyte solutions (ITIES), described in sections 2.4 and 2.5, will now be used to describe a dynamic method based on the passage of electrical current across ITIES. Voltammetry at ITIES (for a survey see [3, 8, 9, 10, 11, 12,18]) is an inverse analogue of potentiometry with liquid-membrane ISEs and thus forms a suitable conclusion to this book. 

As a third special case, consider the mass flow resulting from a pressure difference between the two vessels maintained at a uniform temperature. According to Eq. (6.6.2b) this yields J = —(LuV /T)V P, which is an analogue of electric current flow arising from a difference of electrical potential. Accordingly, it is sensible to introduce a hydraulic permittivity, E, for mass flow, defined as [Why include the minus sign as part of the definition ]... 

The constant of proportionality in the figure is dependait on the permeability k of the porous network. Darcy s law can be r arded as tire fluid flow through porous media analogue of the Ohm s law for flow of electric current. 

There is at present much interest in large cage (cluster) molecules based on carbon [62]. The best known of these is the established Cgo molecule (fullerene) which has exceptional stability and has the highly symmetrical truncated icosahedral structure depicted in Figure 4.7. Derivatives of C o, and carbon nanotubes, currently attract much interest because of their exceptional electrical, mechanical and structural properties. Phosphorus analogues may exist (P is used as a co-catalyst for growing of carbon nanotubes [63,64]). 

Analogue Electric current that is continuous and continuously variable in nature... 

With the establishment of an electrical grid, based on the advocacy of alternating current by Serbian American engineer and inventor Nikola Tesla (1856-1943), a vast assortment of analogue electrical devices were soon developed for consumer use, though initially these devices were no more than electric lights and electromechanical applications based on electric motors and generators. 

The current is analogous to permeation rate, the driving force or voltage is analogous to the concentration gradient or pressure differential, and the electrical resistance is then the analogue of resistance to permeate flow. The resistance to permeate flow can then be said to be Rf. 

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