Theory of potential relaxation after interrupting a steady-state current

This article predicts the chronopotentiometric response when a steady-state reductive voltammetric current is interrupted. Although the ohmic polarization disappears instantaneously, the presence of the double-layer capacitance prevents the cessation of faradaic current. The electrode potential adopts a value that reflects three processes — the continuing arrival of electroactive ions, the incomplete reduction of these ions, and the discharging of the capacitor — all of which proceed at a diminishing rate. A nonlinear differential equation is derived to incorporate these three processes and its dimensionless equivalent is solved as a power series. The form of the solution is shown to depend on whether or not the interrupted current was close to the limiting current of the reduction. Methods of analyzing the experimental chronopotentiogram are discussed. Keywords: current interrupt, potential relaxation, chronopotentiometry.

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Transient Current Density in a Pair of Long Parallel Conductors

Applied Sciences ◽

10.3390/app11156920 ◽

2021 ◽

Vol 11 (15) ◽

pp. 6920

Author(s):

Oldřich Coufal

Keyword(s):

Steady State ◽

Cross Section ◽

Current Density ◽

Circular Cross Section ◽

Transient Current ◽

Constant Current ◽

Voltage Source ◽

Sinusoidal Voltage ◽

Steady State Current ◽

Maximum Current

Two infinitely long parallel conductors of arbitrary cross section connected to a voltage source form a loop. If the source voltage depends on time, then due to induction there is no constant current density in the loop conductors. It is only recently that a method has been published for accurately calculating current density in a group of long parallel conductors. The method has thus far been applied to the calculation of steady-state current density in a loop connected to a sinusoidal voltage source. In the present article, the method is used for an accurate calculation of transient current using transient current density. The transient current is analysed when connecting and short-circuiting the sources of sinusoidal, constant and sawtooth voltages. For circular cross section conductors, the dependences of maximum current density, maximum current and the time of achieving steady state on the source frequency, the distance of the conductors and their resistivity when connecting the source of sinusoidal voltage are examined.

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Electron-magnetohydrodynamic description of a steady-state current flow in a plasma with a three-dimensional localized density perturbation

Plasma Physics Reports ◽

10.1134/s1063780x11070154 ◽

2011 ◽

Vol 37 (9) ◽

pp. 792-801

Author(s):

D. A. Tolstik

Keyword(s):

Steady State ◽

Current Flow ◽

Three Dimensional ◽

Density Perturbation ◽

Steady State Current

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Equivalent magnetization approach for calculating magnetic fields of localized steady‐state current distributions

American Journal of Physics ◽

10.1119/1.16569 ◽

1991 ◽

Vol 59 (3) ◽

pp. 233-235 ◽

Cited By ~ 6

Author(s):

Basilio Carrascal ◽

Gentil A. Estévez ◽

Vicente Lorenzo

Keyword(s):

Steady State ◽

Magnetic Fields ◽

Current Distributions ◽

Steady State Current

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In situ real time monitoring of kinetics of thiol adsorption on gold based on electrochemical steady-state current

Electrochemistry Communications ◽

10.1016/j.elecom.2011.08.042 ◽

2011 ◽

Vol 13 (11) ◽

pp. 1209-1212 ◽

Cited By ~ 4

Author(s):

Joohong Kye ◽

Seongpil Hwang

Keyword(s):

Steady State ◽

Real Time ◽

Real Time Monitoring ◽

Steady State Current ◽

Kinetics Of

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A System for Individualized Dosing of Intravenous Aminophylline Using a Programmable Calculator

PEDIATRICS ◽

10.1542/peds.73.1.64 ◽

1984 ◽

Vol 73 (1) ◽

pp. 64-67

Author(s):

J. Chris Mitsuoka ◽

Richard J. Fleck

Keyword(s):

Steady State ◽

Serum Sample ◽

Drug Exposure ◽

Plasma Concentrations ◽

Dose Administration ◽

Programmable Calculator ◽

Concentration Determination ◽

A Value ◽

Individualized Dosing ◽

History Of

A program that calculates a value of clearance for an individual patient prior to reaching steady state in the early stages of aminophylline therapy is presented. The program is written for the Texas Instruments TI-59 programmable calculator and may be used with or without the PC-100C printer. The program can provide clinically useful information concerning projected plasma concentrations prior to reaching steady state with an accurate history of the dose administration and serum concentration determination. If the patient has not received xanthene therapy prior to admission, only one serum sample is required. If there has been prior drug exposure, a second serum sample is required. An iterative technique, which would be impractical to use without calculator assistance, is employed to make these determinations.

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Redox mediation at poly(o-aminophenol) coated electrodes: Mechanistic diagnosis from steady state polarization curves

Journal of Electrochemical Science and Engineering ◽

10.5599/jese.516 ◽

2018 ◽

Author(s):

Gabriel Ybarra ◽

Carlos Moina ◽

María Inés Florit ◽

Dionisio Posadas

Keyword(s):

Steady State ◽

Polarization Curve ◽

Experimental Measurements ◽

Steady State Current ◽

Thermodynamical Parameters ◽

Reduction And Oxidation ◽

Mediated Reduction ◽

Coated Electrodes ◽

Current Potential ◽

Potential Curves

In this work, the mediated reduction and oxidation of Fe(CN)63-/4- and Fe3+ in poly(o-aminophenol) coated electrodes is analyzed by means of diagnosis diagram based on the features of steady state current-potential curves. This analysis allows to identify the current determining process and to reproduce the experimental characteristics of the polarization curve from the relevant kinetic and thermodynamical parameters with a minimum amount of experimental measurements.

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Super-Fine Structure in the Critical Flow-Rate of Critical Flow Venturi Nozzles

Volume 1: Fora, Parts A and B ◽

10.1115/fedsm2002-31079 ◽

2002 ◽

Cited By ~ 3

Author(s):

Masahiro Ishibashi

Keyword(s):

Fine Structure ◽

Steady State ◽

Discharge Coefficient ◽

Constant Pressure ◽

Pressure Ratio ◽

Critical Flow ◽

Time Intervals ◽

Critical Flow Rate ◽

A Value ◽

Long Time

It is shown that critical flow Venturi nozzles need time intervals, i.e., more than five hours, to achieve steady state conditions. During these intervals, the discharge coefficient varies gradually to reach a value inherent to the pressure ratio applied. When a nozzle is suddenly put in the critical condition, its discharge coefficient is trapped at a certain value then afterwards approaches gradually to the inherent value. Primary calibrations are considered to have measured the trapped discharge coefficient, whereas nozzles in applications, where a constant pressure ratio is applied for a long time, have a discharge coefficient inherent to the pressure ratio; inherent and trapped coefficients can differ by 0.03–0.04%.

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Exploration of an Electroactive Polymer as an Actuator for Microrobotics

MRS Proceedings ◽

10.1557/proc-785-d8.5 ◽

2003 ◽

Vol 785 ◽

Cited By ~ 1

Author(s):

C. Bielmeier ◽

W. Walter

Keyword(s):

Steady State ◽

Power Consumption ◽

Parallel Plate ◽

Electroactive Polymers ◽

Electroactive Polymer ◽

Low Power Consumption ◽

Parallel Plate Capacitor ◽

Steady State Current ◽

A Current ◽

Over Time

ABSTRACTThe development of lightweight low power consumption actuators is critical to the development of micro-robotics. Electroactive Polymers (EAP), i.e. Nafion N-117, meet these requirements. In the actuation of an EAP, the current does not remain constant over time. The development of a circuit model of current draw over time to best predict a current dynamic has been explored. While the material mimics a parallel plate capacitor, it has been found that capacitance plays no role in achieving steady state current levels. This development is critical to understanding and developing the material as an actuator.

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