A New Theory of Potential Step Chronoamperometry at a Microdisk Electrode: Complete Explicit Semi-Analytical Formulae for the Faradaic Current Density and the Faradaic Current

2016 ◽  
Vol 199 ◽  
pp. 1-11 ◽  
Author(s):  
L.K. Bieniasz
Keyword(s):  
Current Density ◽  
Potential Step ◽  
Faradaic Current ◽  
Analytical Formulae

Applicability of the potential step relaxation technique in the nonlinear current density—overpotential range

1987 ◽  
Vol 32 (12) ◽  
pp. 1777-1782 ◽  
Author(s):  
Z. Nagy ◽  
M. Minkoff ◽  
G.K. Leaf ◽  
R.H. Land
Keyword(s):  
Current Density ◽  
Relaxation Technique ◽  
Potential Step

A transition metal oxofluoride offering advantages in electrocatalysis and potential use in applications

2016 ◽  
Vol 188 ◽  
pp. 481-498 ◽  
Author(s):  
H. Svengren ◽  
N. Torapava ◽  
I. Athanassiadis ◽  
S. I. Ali ◽  
M. Johnsson
Keyword(s):  
Current Density ◽  
Water Oxidation ◽  
Hydrophobic Surface ◽  
Surface Sites ◽  
Faradaic Current ◽  
Crystallite Surface ◽  
Potential Use ◽  
A Current ◽  
Shape And Size

The recently described solid solution (Co,Ni,Mn)3Sb4O6F6has proved stable and efficient as a catalyst for electrocatalytic water oxidation. The end component Co3Sb4O6F6was found to be most efficient, maintaining a current density ofj= 10 mA cm−2at an overpotential of 443 mV with good capability. At this current density, O2and H2were produced in the ratio 1 : 2 without loss of faradaic current against a Pt-cathode. A morphological change in the crystallite surface was observed after 0.5 h, however, even after 64.5 h, the overall shape and size of the small crystallites were unaffected and the electrolyte contained only 0.02 at% Co. It was also possible to conclude fromin situEXAFS measurements that the coordination around Co did not change. The oxofluorides express both hydrophilic and hydrophobic surface sites, incorporate a flexible metalloid element and offer the possibility of a mechanism that differs from other inorganic catalytic pathways previously described.

scholarly journals Electrochemical properties of 316L stainless steel with culturing L929 fibroblasts

2005 ◽  
Vol 3 (9) ◽  
pp. 495-505 ◽  
Author(s):  
Sachiko Hiromoto ◽  
Takao Hanawa
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
Current Density ◽  
316L Stainless Steel ◽  
Step Test ◽  
Type I ◽  
L929 Cells ◽  
Potential Step ◽  
Collagen Coating ◽  
316L Steel

Potentiodynamic polarization and impedance tests were carried out on 316L stainless steel with culturing murine fibroblast L929 cells to elucidate the corrosion behaviour of 316L steel with L929 cells and to understand the electrochemical interface between 316L steel and cells, respectively. Potential step test was carried out on 316L steel with type I collagen coating and culturing L929 cells to compare the effects of collagen and L929 cells. The open-circuit potential of 316L steel slightly shifted in a negative manner and passive current density increased with cells, indicating a decrease in the protective ability of passive oxide film. The pitting potential decreased with cells, indicating a decrease in the pitting corrosion resistance. In addition, a decrease in diffusivity at the interface was indicated from the decrease in the cathodic current density and the increase in the diffusion resistance parameter in the impedance test. The anodic peak current in the potential step test decreased with cells and collagen. Consequently, the corrosion resistance of 316L steel decreases with L929 cells. In addition, collagen coating would provide an environment for anodic reaction similar to that with culturing cells.

Activated Prominences; Mechanisms for Activation and Eruption

1979 ◽  
Vol 44 ◽  
pp. 307-313
Author(s):  
D.S. Spicer
Keyword(s):  
Pressure Gradient ◽  
Density Gradient ◽  
Current Density ◽  
Convective Instability ◽  
Tearing Mode ◽  
Magnetic Shear ◽  
Long Wavelength ◽  
Ideal Mhd ◽  
Gradient Change ◽  
Accelerated Particles

A possible relationship between the hot prominence transition sheath, increased internal turbulent and/or helical motion prior to prominence eruption and the prominence eruption (“disparition brusque”) is discussed. The associated darkening of the filament or brightening of the prominence is interpreted as a change in the prominence’s internal pressure gradient which, if of the correct sign, can lead to short wavelength turbulent convection within the prominence. Associated with such a pressure gradient change may be the alteration of the current density gradient within the prominence. Such a change in the current density gradient may also be due to the relative motion of the neighbouring plages thereby increasing the magnetic shear within the prominence, i.e., steepening the current density gradient. Depending on the magnitude of the current density gradient, i.e., magnetic shear, disruption of the prominence can occur by either a long wavelength ideal MHD helical (“kink”) convective instability and/or a long wavelength resistive helical (“kink”) convective instability (tearing mode). The long wavelength ideal MHD helical instability will lead to helical rotation and thus unwinding due to diamagnetic effects and plasma ejections due to convection. The long wavelength resistive helical instability will lead to both unwinding and plasma ejections, but also to accelerated plasma flow, long wavelength magnetic field filamentation, accelerated particles and long wavelength heating internal to the prominence.

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