Surface voltage

Here, clayer = Ksjdlayer is the capacitance per unit area (in farads/m2) of the layer. The surface voltage Vlayer can be related to the accumulated surface charge a/ (in C/m2) by the following equation ... 

Analysis of the time and temperature dependent decay of the surface voltage on an amorphous film after charging, but prior to exposure (xerographic dark decay), and of residual decay after exposure can (in combination) be used to map the density of states. 

Surface voltage decay was measured with a Trek Model 341 high voltage electrostatic voltmeter (ESVM). The ESVM drives the potential of a probe body to the same potential as the film surface voltage. This device measures the voltage independent of distance within 5 mm of the film surface without causing current flow, which would modify the data. After poling, the corona needle was removed and the probe of the ESVM was placed 3 mm from the film surface. 

Figure 2. Surface voltage decay as a function of time for corona poled PS (O) and PMMA ( ) films doped with 4 wt.% DANS. Films poled at -3000V (0.6 cm air gap) for 15 min at 25°C.

Fig. 5.4. Schematic constant-current (CC) measurement the controller voltage over time has to be equivalent to the change of the surface voltage, to remain a fixed working point. The change in the pH value can be calculated by a proportional change in the controller voltage.

Fig. 4. Photoinduced-discharge (PID) curves of a-Si H photoreceptor (multiple-layer type), (a) Surface voltage plotted as a function of exposure tim e for the following light intensities at 600 nm (1) 1.6 fiW cm-2, (2) 0.32, (3) 0.16, and (4) 0 08. (b) The photocurrent (estimated from the time derivative of the PID curves) versus surface voltages for a-Si H photoreceptor (a-Si B, 10 ppm, 10 /an thick exposure 600 nm, 2.0 X 1012 photons cm-2 sec-1). [From Oda eta/. (1981b).]...

Cell-surface voltage-dependent Ca channels are opened, facilitating extracellular Ca influx into the /8-ceU. 

Fig. 7.5 Block diagram of a method of measuring surface voltage with a positive-feedback electrometer...

Figure 4.10 OTA and ZAN LC-MS3 extracted ion chromatograms of a wine spiked with OTA at a concentration of 0.1 ng/mL and internal standard ZAN (lOng/mL). Above signal m/z 239 + 341 of OTA below signal m/z 207 + 189 + 163 of ZAN. Analytical conditions C18 (3 x 250mm 5 pm) column, binary solvent A) H2O/0.1% formic acid/sodium acetate 0.6mM and B) methanol/0.1% formic acid. Gradient program 50% A for 1 min, from 50% to 20% of A in 7 min, isocratic for 4 min, 20-50% A in 3 min, isocratic for 3 min (flow rate 0.5mL/min). SACI vaporizer temperature 400 °C entrance capillary temperature 150 °C SACI surface voltage 50 V surface temperature 110°C nebulizing sheath gas N2 at flow rate 9 L/min curtain gas 2 L/min spray needle voltage set to 0 V. (Adapted from Flamini et al, 2007, RCM) 21, (22), 3737-3742...

J-V characteristics helps define the interelectrode phenomena such as electron and ion emission from electrodes, sheath height at the electrode surface, voltage loss in the plasma, and so on. But it is difficult to discuss those phenomena in detail. In following section, we discuss the correlation between Pmax and some temperatures, apart from J-V characteristics. 

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