Voltage ramp , electrical

The basic instrumentation required for controlled-potential experiments is relatively inexpensive and readily available commercially. The basic necessities include a cell (with a three-electrode system), a voltammetric analyzer (consisting of a potentiostatic circuitry and a voltage ramp generator), and an X-Y-t recorder (or plotter). Modem voltammetric analyzers are versatile enough to perform many modes of operation. Depending upon the specific experiment, other components may be required. For example, a faradaic cage is desired for work with ultramicroelectrodes. The system should be located in a room free from major electrical interferences, vibrations, and drastic fluctuations in temperature. 

To test the electrical behavior of the cell, one can apply a voltage stimulus (i.e., voltage ramp or step) and monitor the current (voltage clamp). Other than in technical systems, the application of a current ramp (or step) and monitoring the voltage... 

The key features of the voltage-ramp soft-start unit are that it can softly start varying loads, it does not limit motor torque, and it is easily adjusted. In general, it is desirable to bring the load up to speed as quickly as possible given the mechanical and electrical power distribution system constraints. 

Secondary electron multiplier for high amplification factors, usually built from discrete dynodes which are electrically connected by resistors to provide a voltage ramp across the number of dynodes (contrary to a CDEM). 

Experimental study of the acoustic emission and partial discharge current pulses have been carried out on the insulating foils for applied constant and ramp voltage. An insnlating foil with metal electrodes on the sides creates a parallel plate capacitor. This metal-insulator-metal (MIM) system has electrical characteristics represented by a constant value of conductivity and permittivity in the low electric field. 

Applying of a ramp voltage on MIM structure creates the polarization current, which is a result of the slow polarization phenomena. A relaxation time of this polarization depends on the applied electric field and it is strongly related to the appearance of the partial discharges (Macur Domansky 1991). 

Planar bilayer membranes are characterized by their electrical response since the insulating bilayer membrane and the two conducting ionic solutions are electrically equivalent to a capacitor with the membrane as the dielectric. The current through a capacitor is directly proportional to the rate of change of the voltage on the capacitor, i = C dV/dt. The capacitance, in turn, is related to the thickness of the membrane and its dielectric constant. The membrane capacitance is determined by applying a ramp potential with a constant dV/dt across the membrane to give a constant current that can be converted to the mem-... 

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