Voltage, normalised

First we must normalise some quantities, to make them compatible with the other dimensionless parameters already used. We refer to the normalisation formulae on p.26. Recall that we have normalised voltage by the factor and that the time unit r for LSV is equal to (v being the sweep rate), or the time the sweep takes to traverse one normalised potential unit V-... 

By introducing the normalised voltage U = U/ Um a quantity that is important for further theoretical description of electrochemical discharges, one obtains a particularly elegant relation for the Wehnelt interrupter (Fig. 2.6) ... 

A micro computer system allowed voltage and current measurements to be synchronised plus data logging and averaging of measurements. Alongside each "measurement" foil was a "control" foil, coated with paint plus a protective epoxy coating, which did not corrode and allowed resistance measurements to be normalised. 

Fig. 71. Normalised photocurrent-voltage curves calculated from eqn. (492) for a p-type semiconductor with 0O = 1014cm 2s 1, a = 3.3 104cm 1,Ar = 107cm3cm-1, kt = 108cm3s ky = 104cms 1, Na = 8 x 10I6cm 3,e,c = 11, Ln = 7 x 10 6 cm, Nt values (cm-2) are indicated on the figure.

Fig. 2.20. Failure voltage T4 for the whole range of p in the dielectric breakdown simulation experiment with LED. The full line denotes the shortest path (normalised with the Vb value at the point p = 0) as determined by Duxbury et al. (unpublished). Different symbols indicate different realisations of the sample (Benguigui and Ron 1994).

By combining these relations, one gets the normalised mean stationary current characteristics for terminal voltages lower than the critical voltage (i.e. U < 1) ... 

An interesting consequence of these calculations is that the normalised mean stationary current—voltage characteristics are similar for different electrodes and electrolytes. An example is shown in Fig. 3.19 where the normalised mean current—voltage characteristics for a sodium hydroxide solution with different concentrations is depicted. 

Figure 4.7 Step input for a terminal voltage lower than the critical voltage (a) bubble coverage fraction 0 step input (b) normalised current J step input.

For practical applications, one should be able to estimate the normalised heat power k as a function of the machining voltage. A qualitative estimation can be obtained if it is assumed that each discharge transfers a similar heat quantity qE to the workpiece. The heat power P0 can be related to the mean number of discharges using Equation (4.38) ... 

Figure 5.5 shows the expected material removal rate as a function of the normalised heat power k for various tool-electrode radii b. In order to determine the relation between k and the machining voltage U, one has to compare these results with experimental data. 

Figure 5.6 (a) Experimental glass machining speed dz/dt for a 0.4 mm stainless steel tool-electrode as a function of the machining voltage U. (b) Normalised heat power k as a function of the machining voltage U [65],... 

In Figure 21.2, we show the shift of the main peak in the Hg p-PES for different voltages applied (effect for D2 excitation is equal). For a discussion of the EDC, see [33]. The shift is normalised to the main peak of the p-PES spectrum at the grounded electrode, here at position 5, for zero voltage applied. 

Figure 16 shows the theoretically predicted influence of the normalised frequency, f, on the phase angle between current and voltage, , along with experimental verification [70] using the ferri-ferrocyanide reversible couple... 

Fig. 11. (A) Voltage dependence of for the activation of For Fp< -50 mV, the time constants were evaluated from tail current records. The different symbols represent separate experiments. (B) Voltage dependence of the relaxation time constants of the gating currents. All results were normalised to a standard temperature of 6.3°C assuming m = 3. For V > -50 mV, t (F) was measured during the pulses for Fp < -50 mV, it was measured from the tail of the gating current and F, was varied. (O, , A, T, A, ) in fibres perfused with high Cs (the different symbols represent different experiments) (A, B, ) in fibres perfused with low Cs (50 mM CsF plus 900 mM sucrose), plotted with membrane potentials shifted 9mV in a negative direction (t(F) values from Table3 in [41]). The lines were computed to give a least-squares best fit of the points in A or in B (for parameters see text). (Adapted from Keynes and Rojas [38].)...

Fig. 12B shows the voltage dependence of the normalised steady-state distribution of charges, that is to say the q Vp, oo)/Q — V curve. It may be seen that above + 40 mV, there was no further asymmetrical transfer of charge, so that saturation of the system of mobile charges had indeed been achieved. The curve in Fig. 12B was computed by the least-squares best fit with the experimental points (as for Fig. 12A), with C/A = (0.2450 0.0088) and Z) - B = (54.0 1.80)/V. 

Fig. 8.4 Normalised output voltage Vo/E versus the duty ratio d for different values of the inductor resistance Ri...

The valve coefficients for the four valves are fixed at the values given by (10.63), (10.64), (10.66) and (10.67) to obtain the open-loop dynamic response of the SOFC. Step changes are made in the load current from 100 to 80 A at 500 s and from 80 to 90 A at 2000 s. The dynamic responses of the cell voltage, current, FU and OU to the step changes of load current, the data being normalised with respect to the initial steady-state conditions (Voltage = 0.609036 V, Current = 100 A, FU = 0.8 and OU = 0.125), are shown in Fig. 10.8a. 

Fig. 10.8 Dynamic response curves for (a) voltage, current, FU and OU normalised to their initial values and (b) species partial pressures and cell temperature...

The physical significance of K is that each normalised current/voltage plot in the form of f/fiim vs 6 (= P/RT(E — ) where E is the potential) is a function only... 

Normalised current-voltage characteristics of melt-spun PP fibres containing 10 and 15 vol% of carbon nanofibres drawn to different draw ratios (DR). Reproduced from Ref. 213. 

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