Onsager L (1934) Deviations from Ohm s law in weak electrolytes. J Chem Phys 2 599 [Pg.76]

The voltages at which the J-V curve deviates from the power law Vl+1 and at which it approaches Ohm s law are of general interest. Calculations have been made for a typical case, a 10% difference is taken as the experimental tolerance. The results are shown in Fig. 3.16. The voltages of deviation from the power law (dashed curve) and that of approach to Ohm s law (solid curve) are shown for different values of the injection barrier. It is seen that these voltages are large for small value of the barrier and decrease rapidly as the barrier increases. [Pg.53]

The reason why power sources exhibit transient voltage response and therefore deviate from Ohm s law is the presence of capacitive elements in parallel with resistive ones, for example, a double-layer capacitance in parallel with Re and pseudocapacitance associated with diffusion process in parallel with dififiision resistance. [Pg.431]

Some organic compounds, such as the complex copper/TCNQ (see Fig. 11.11), possess the property of current-voltage non-linearity and deviate heavily from Ohm s law. At some threshold voltage their electrical resistance drops precipitously by orders of magnitude (104) [Pg.351]

This Ohm s law representation of the pressure-flow relationship forms the basis for measurements of airway resistance and is the principle on which several flow-measuring devices are based. The pressure required to move gas u r conditions of turbulence is always greater than that required to achieve the same flow under laminar conditions, as additional pressure (or energy) is required to accelerate molecules in directions other than the direction of bulk flow. This will be manifested as an upward curve and deviation from linearity on a plot of flow (jc axis) versus pressure drop (y axis). [Pg.544]

The only part of the electrolyte where there is substantial deviation from electroneutrality is in the charged double layer. However, this problem is avoided by introducing the abovementioned discontinuity in the electric potential. For electrolytes with constant composition, a conservation of current and Ohm s law form the model equations. This equation can be derived from Faraday s law and the electroneutrality condition. Faraday s law gives the current density vector as a function of the transport of ions [Pg.395]

The observation of non-ohmic conductivity, below the temperature which corresponds to the onset of three-dimensional SOW order, strongly suggests that the nonlinearity is associated with the appearance of SDW. Indeed, it is difficult to explain the low threshold fields, at which deviations from Ohm s law are observed by models based on a single-particle picture. First, we note that the threshold fields are far too low, for Zener breakdown to be relevant. [Pg.255]

On the other hand, the current flow disrupts the interface in the case of electrochemical interfaces and ionic junctions. The voltage across the interface (or the junction voltage for an ionic junction) is generally different from that observed at open circuit. It depends a priori on the parameters of the system and deviates from a linear law, such as Ohm s law. Most often it can be assumed that the double layer thickness is much lower than that of the diffusion layers . Typically, one ends up with the following [Pg.210]

For an Ionic conductor (or similarly for a semiconductor), applying this method is, by definition, a much more complicated affair measuring currents or potential differences requires metallic contacts to be put in place with the conductor in question. A minimum of two electrochemical interfaces must therefore be introduced, which generally leads to deviations from Ohm s law. It is assumed that in usual experimental conditions (see below) one can keep the influence of these interfacial phenomena to a minimum in the relationship between Uand I. [Pg.202]

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