The backbone of the industrialized world is comprised of refined, zerovalent metal, a material which thermodynamically favors an oxidative return to more chemically stable states. There are many methods used to slow or delay this process, such as protective coatings, sacrificial anodes, and alloys, but no method can entirely prevent corrosion. This body of work instead proposes detecting the earliest chemical markers of corrosion: that is, metal ions as they solubilize from a metal surface. Such information would allow maintenance personnel to make informed decisions about the necessity or lack thereof of preventive maintenance, and intervene before advanced damage has a chance to occur. This dissertation finds that hydrogel-based sensors are capable of such detection and offer a multisensory response, with colorimetric, electrical, volumetric and vibrational changes. Both the colorimetric and electrical trends were calibrated and used for quantification of metal ions both in solution and directly from metal substrate surfaces. Observing how the hydrogels responded to various metal ions contributed to a greater understanding of how ion-headgroup associations can affect the sensory responses of a hydrogel, something that can be exploited in future sensor work. The ability of the sensors to detect ions directly from metal surfaces allowed for an investigation of the protective quality of fatty acids as corrosion inhibitors. A range of chain lengths were tested using the hydrogels, and the comparison to current characterization techniques showed good correlation. This accessible technique, beyond contributing to the current meager literature of fatty acids as corrosion inhibitors, can also allow for the determination of acceptable benchmarks of corrosion, information that is sorely needed to efficiently steward global infrastructure.

The potential use of sodium propionate as a corrosion inhibitor for mild steel in aqueous media is investigated using a range of electrochemical and surface analytical techniques. The use of sodium propionate for the inhibition of mild steel corrosion is discussed, and the effective pH range of sodium propionate using various buffers is investigated. The effectiveness of sodium propionate as an inhibitor for mild steel pitting corrosion in the presence of various concentrations of CI- is studied. The effect of some oxidants, IO3-, BrO3-, NO32- on the anodic behaviour of mild steel in deaerated 0.01M carboxylate solutions of acetate, propionate, formate, succinate and salicylate is investigated. The critical temperature for effective inhibition of mild steel corrosion with sodium propionate is established, and the chemical composition of the film formed on mild steel surface in sodium propionate solution is studied using surface sensitive Fourier transform infrared spectroscopy FTIR. The efficiency of sodium propionate is compared to that of conventional inhibitors and a mechanism for the inhibition of mild steel corrosion with sodium propionate is proposed. / Doctor of Philosophy (PhD)

Thesis (Ph. D.)--Ohio State University, 2006. / Full text release at OhioLINK's ETD Center delayed at author's request

Thesis (M.S.)--University of Kentucky, 2004. / Title from document title page (viewed June 21, 2004). Document formatted into pages; contains x, 63 p. : ill. Includes abstract and vita. Includes bibliographical references (p. 61-62).

Thesis (Ph.D.)--Ohio University, June, 2009. / Release of full electronic text on OhioLINK has been delayed until June 1, 2010. Includes bibliographical references (leaves 184-194)

Thesis (Ph.D.)--Ohio University, June, 2009. / Title from PDF t.p. Release of full electronic text on OhioLINK has been delayed until June 1, 2010. Includes bibliographical references (leaves 184-194)

M. Tech. Chemical Engineering. / Discusses the corrosion of mild steel due to sulphate ions together with chloride ions in concrete reinforcement in alkaline media can be limited or even eliminated by the introduction of laser surface irradiation on the mild steel material.

No description available.

Plasma Source Ion Implantation (PSII) is the process of implanting high energy ions [10-50 keV] into metallic targets, by pulsing them negatively whilst immersed in a background plasma. PSII achieves surface hardening, and increased wear and corrosion resistance. Numerous papers have been published describing numerical simulations and models of the PSII process, most of which have been limited to one dimension. This thesis presents the results of work carried out III the Plasma Processing Laboratory at the University of Natal, Durban, during 1994-1995. In particular, measurements of two-dimensional plasma sheath effects due to spherical and complex shaped targets are compared with a particle-in-cell simulation code. The simulation results are used to define a relationship between the plasma potential of the sheath edge and the saturation currents. Thus allowing for the saturation currents to be used to trace sheath evolution. These results are compared with the experimental measurements from the spherical target. Results from the rectangular and complex saw-tooth targets show a lack of sheath conformality. The ion saturation currents were susceptible to electron swamping, which occured in localised regions associated with target structure. It is thought that secondary electrons ejected from the target are focused and accelerated by the high target potential into these regions, where they swamp the ion current. / Thesis (M.Sc.)-University of Natal, Durban, 1996.

No description available.