Zn-Mo coatings are very promising environment friendly anticorrosive coatings as replacement materials for cadmium and chromium (VI) based conversion layers. Electrodeposition has become a favorable technique in fabricating coatings due to its low cost, ease of use, and overall experimental control of coating quality. Very little research so far has been done for the electrodeposition of Zn-Mo coatings under alkaline conditions. In this work, Zn and Zn-Mo coatings were electrochemically deposited on stainless steel from an aqueous alkaline citrate solution. An organic compound, vanillin, was added to the electrolyte as a leveling agent for improving interlayer adherence and corrosion resistance of Zn-Mo coatings. Ni-Mo alloys have been known to possess high tensile strength and excellent corrosion protection of steels, and MoTe2 layers have a potential for the application in anticorrosive coatings due to their hydrophobic properties. In this study, MoTe2-Ni-Mo coatings were deposited on stainless steel using both sputtering and electrodeposition methods. These coatings with high corrosion resistance and other desirable properties are in demand in the oil and gas industry since they can protect and thus extend the lifetime of the underlying materials when exposed to aggressive environments. The Zn-Mo and MoTe2-Ni-Mo coatings were evaluated for chemical composition and corrosion behavior using different types of instrumental and electrochemical techniques. The addition of vanillin to the electrolyte did not change the crystalline structure or composition of the Zn-Mo coating, however, the corrosion resistance of the coating was significantly improved by the leveling effect of vanillin during the electrodeposition. The corrosion resistance of the Ni-Mo coating was also enhanced by applying the hydrophobic MoTe2 monolayer on the top surface.

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This dissertation details an investigation into the use of laser pulses from a titanium:sapphire regenerative amplifier laser system to vaporize analytes in ambient air for mass spectral analysis. The laser system was modified to operate in one of two distinct modes. In femtosecond (fs) mode the laser produced 2.5 mJ, ~60 fs laser pulses centered at 800 nm. In nanosecond (ns) mode the laser produced 2.4 mJ, ~10 ns laser pulses centered at 800 nm. Using appropriate optical components the laser pulse energy was attenuated to achieve pulses varying from 0.15 mJ to 2.0 mJ. Laser pulses were used to vaporize liquid and solid samples on different substrates. The laser vaporized material was captured and ionized by an electrospray source and then detected via a mass spectrometer instrument. It was discovered that samples on glass substrate could be vaporized by fs laser pulses, but not by ns laser pulses. Samples on metal substrate were successfully vaporized by both fs and ns laser pulses. Low energy ns laser pulses were less efficient than fs laser pulses of the same energy for vaporizing off metal substrate. A comparison of vaporization from aluminum, copper and stainless steel substrates revealed limited vaporization from copper by ns laser pulses. The electrospray ionization (ESI) mass spectral response of wet and dry proteins on stainless steel was similar for both fs and ns laser pulses. Experiments to test the capabilities of ns laser electrospray mass spectrometry (ns-LEMS) revealed that sample vaporization was limited to analysis on metal surfaces. This dissertation details methods for femtosecond laser electrospray ionization (fs-LEMS) to be used to quantify non-covalent protein-ligand interactions. Hen egg white lysozyme (HEWL) and N,N’,N”-triacetylchitotriose (NAG3) interactions were quantified via dissociation constant (Kd) measurements. The Kd for HEWL and N,N’,N”,N”’-tetraacetylchitotetraose (NAG4) were also measured. This dissertation also reports a miniaturized flowing atmospheric pressure afterglow (micro-FAPA) for use as an alternative ionization source of fs-laser vaporized analytes. Loratadine pills were vaporized and reacted with the gas stream from the micro-FAPA source to generate ions which were then detected by a mass analyzer. The ions detected varied in distribution as a response to the distance the sample was vaporized from the ion source. Complexed samples were tested and molecular assignments were difficult due to the numerous pathways for ion formation. The use of an ion filter to decrease the energy imparted on sample molecules during the ionization process of the micro-FAPA is also reported. / Chemistry