Relationship between Capacitive Loop Observed in Impedance Spectrum and Pore Structure of Mortar

Nozomu Someya; Yoshinao Hoshi

doi:10.3323/jcorr.68.270

Relationship between Capacitive Loop Observed in Impedance Spectrum and Pore Structure of Mortar

Zairyo-to-Kankyo ◽

10.3323/jcorr.68.270 ◽

2019 ◽

Vol 68 (10) ◽

pp. 270-273

Author(s):

Nozomu Someya ◽

Yoshinao Hoshi

Keyword(s):

Pore Structure ◽

Impedance Spectrum ◽

Capacitive Loop

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Corrosion Properties of Arc Spray Zn-25Al and Zn-50Al Coating in Marine Environment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.239-242.1215 ◽

2011 ◽

Vol 239-242 ◽

pp. 1215-1218

Author(s):

Qing Jun Zhu ◽

Kai Wang

Keyword(s):

Electrochemical Impedance ◽

Impedance Spectrum ◽

Electrochemical Impedance Spectrum ◽

Natural Seawater ◽

Corrosion Properties ◽

Arc Spray ◽

Seawater Corrosion ◽

Capacitive Loop ◽

Corrosion Behaviors ◽

Protection Potential

Zn-25Al and Zn-50Al coatings were prepared by arc spray in mild carbon steel Q235. The corrosion behaviors of these coatings were studied by potentiodynamic polarization test in natural seawater, corrosion potentials and electrochemical impedance spectrum. The results show that the Ecorr of Zn-25Alcoating is -1.025V (SCE) and the Ecorr of Zn-50Al coating is -0.997V (SCE) at the beginning of the immersion. The Ecorr of the Zn-50Al coating is not stable as the Zn-25Al coating. Self-corrosion potential of Zn-25Al coating is lower than Zn-50Al coating. Zn-25Al can provide lower protection potential and promising current to protect the substrate from corrosion than Zn-50Al. The EIS of these two coatings reveal single capacitive loop. The anti-corrosion properties of Zn-25Al coatings are better than that of Zn-50Al coatings.

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Correlation of Pore Structure and Permeability by SEM-Image Analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180896 ◽

1990 ◽

Vol 48 (1) ◽

pp. 428-429

Author(s):

C. A. Callender ◽

Wm. C. Dawson ◽

J. J. Funk

Keyword(s):

Image Analysis ◽

Pore Structure ◽

Imaging System ◽

Pore Space ◽

Simulation Models ◽

Image Analyzer ◽

Imaging Data ◽

Sem Images ◽

Thin Sections ◽

Rock Types

The geometric structure of pore space in some carbonate rocks can be correlated with petrophysical measurements by quantitatively analyzing binaries generated from SEM images. Reservoirs with similar porosities can have markedly different permeabilities. Image analysis identifies which characteristics of a rock are responsible for the permeability differences. Imaging data can explain unusual fluid flow patterns which, in turn, can improve production simulation models.Analytical SchemeOur sample suite consists of 30 Middle East carbonates having porosities ranging from 21 to 28% and permeabilities from 92 to 2153 md. Engineering tests reveal the lack of a consistent (predictable) relationship between porosity and permeability (Fig. 1). Finely polished thin sections were studied petrographically to determine rock texture. The studied thin sections represent four petrographically distinct carbonate rock types ranging from compacted, poorly-sorted, dolomitized, intraclastic grainstones to well-sorted, foraminiferal,ooid, peloidal grainstones. The samples were analyzed for pore structure by a Tracor Northern 5500 IPP 5B/80 image analyzer and a 80386 microprocessor-based imaging system. Between 30 and 50 SEM-generated backscattered electron images (frames) were collected per thin section. Binaries were created from the gray level that represents the pore space. Calculated values were averaged and the data analyzed to determine which geological pore structure characteristics actually affect permeability.

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