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Published in Carl W. Hall, Laws and Models, 2018
The Buoyancy number equals the Grashof number divided by the Reynolds number squared. Keywords: buoyant, convection, viscous Sources: Bolz, R. E. and Tuve, G. L. 1970; Land, N. S. 1972; Parker, S. P. 1992. See also ARCHIMEDES BURGERS MODEL--SEE VISCOELASTIC MODELS (MATERIALS) BUTLER-VOLMER LAW For charge transfer control of an electrochemical reaction, the reaction rate depends mainly on the exchange current density and on the overpotential of the electrode, and is calculated by the following equation which gives the current given by half-cells in electrochemical reactions: I = Io[exp(a Fs/RT) – exp(c F s/RT)] where I Io a c F s R T Ee = = = = = = = = = current density exchange current density anodic charge transfer coefficient cathodic charge-transfer coefficient Faraday constant overpotential, E – Ee gas constant, 8.314 J/mol-K absolute temperature equilibrium electrode potential
Damascene Copper Electroplating
Published in Robert Doering, Yoshio Nishi, Handbook of Semiconductor Manufacturing Technology, 2017
With no applied potential and no imposed current flow across the interface between a metal and a solution, an equilibrium potential exists between the two. This potential is often known as the rest potential. Once potential is shifted from the equilibrium potential by an external power source, a current will be driven across the interface. Under conditions typical of most plating processes, this current density (I) is approximated by an exponential relationship known as the Tafel equation. I=i0[e−αnFη∕RT] where i0, exchange current density; α, charge transfer coefficient; η, applied potential (V); T, absolute temperature; R, gas constant.
Defects with Existing Standards
Published in Paul M. Chess, Cathodic Protection for Reinforced Concrete Structures, 2019
where I: electrode current, AA: electrode active surface area, m2j: electrode current density, A/m2 (defined as i = I/A)j0: exchange current density, A/m2E: electrode potential, VEeq: equilibrium potential, VT: absolute temperature, Kn: number of electrons involved in the electrode reactionF: Faraday constantR: universal gas constantαc: cathodic charge transfer coefficient, dimensionlessαa: anodic charge transfer coefficient, dimensionlessη: activation overpotential (defined as η=(E−Eeq)).
Electrochemical characterization of a Porphyridium cruentum-modified carbon paste electrode by cyclic voltammetry
Published in Instrumentation Science & Technology, 2018
Maria Zaib, Muhammad Makshoof Athar
According to Laviron,[31] the slope of plot Ep versus log υ is equal to 2.3 RT/α nF or 2.3RT/(1-α)nF for cathodic and anodic peaks, respectively. Using the slopes of the plots from Eqs. (11) and (12), the value of α n is found to be 0.549 and 0.536 for modified and bare electrodes. As this is one electron system (n = 1), the value of charge transfer coefficient remains the same.