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Single Point Incremental Forming (SPIF) is a die-less sheet metal forming method. Because SPIF does not use custom tooling, this process allows for parts to be made at low cost and short lead times. In this thesis electric current is applied through the tool to alter the formability of samples formed with SPIF. The research goal of this work is to determine if formability is effected by resistive heating alone or if there is some formability change due to the current interacting with the material. An apparatus that allows electrical current to be applied through the tool during forming is designed and implemented. A method is also developed to allow the contact area between the tool and sheet to be estimated, with particular focus on developing a method that allows for experimental measurement. The effect of applied current on formability is estimated by evaluating the maximum wall angle that can be formed in a single pass, using a variety of tool sizes and current settings. Using the contact area model to estimate current density, a signicant increase in formability is found at a current density range that agrees with previously published literature on electrically assisted forming of the same material. The results show that across multiple tool sizes, a significant increase in formability is observed when applying a current density (A/mm2) larger than the current threshold density published in the literature. A study is also performed to test the performance of a set of novel tool shapes. By using parabolic tools, it was found that formability can be improved while maintaining low surface roughness. Finally, a series of case studies are presented documenting the production several parts for a variety of design groups and researchers at Queen's University. These case studies provide examples for the uses of SPIF, as well as document the methods used to produce these parts in greater detail than is present in the literature. / Thesis (Ph.D, Mechanical and Materials Engineering) -- Queen's University, 2013-11-29 16:06:51.964

The objective of this thesis is to examine the photophysical and structural properties of Ru(II)/Re(I) based bimetallic complexes based on p-[N-2-(2’-pyridyl)benzimidazolyl]-[N-2-(2’-pyridyl)indolyl]-benzene (L1) ligand, as well as the photophysical and photochemical properties of N^C-chelate 4-coordinate organoboron compounds that contain a metal acetylide group. Ligand L1 was synthesized and fully characterized. Due to the incorporation of two distinct chelating sites, an N^N-chelate site and an N^C-chelate site, L1 has been found to be very effective in selective binding to two different metal ions. Two new heterobimetallic complexes Ru(II)-Pt(II) and Ru(II)-Pd(II) using L1 as the bridging ligand were prepared and fully characterized. All Ru(II)-containing complexes have been found to be luminescent. The Pt(II) unit appears to enhance phosphorescent efficiency of the Ru(II) unit while the Pd(II) unit has little influence. Using L1 as the bridging unit, two new Re(I) based heterobimetallic complexes Re(I)-Pt(II) and Re(I)-Pd(II) were also successfully synthesized. Results indicate that there is communication between the two different metal centers. The preliminary results indicated that the mononuclear Re(I) complex based on L1 is a promising candidate for the electrocatalytic CO2 reduction. Pd(II) and Pt(II) complexes were synthesized with an atropisomeric bis-pyridyl chelate ligand bis{3,3’-[N-Ph-2-(2’-py) indolyl]} (L4). To examine the potential use of the trans-chelate L4 ligand in oxidative coupling reactions catalyzed by Pd(II) compounds, acetoxylation of arenes by PhI(OAc)2 using PhI(OAc)2/L4 (2:1) as the catalyst was examined and found to accelerate the reaction, but lower the overall yield. Finally, to examine the impact of metal ions on photochromic properties of N^C-chelate organoboron compounds, three metal acetylide compounds that contain a photo-active N^C-chelate BMes2 unit (B(ppy)Mes2) were prepared and fully characterized. The studies indicated that by taking advantage of different heavy metals the photoisomerization quantum efficiency of the boron chromophores can be readily tuned through the adjustment of 3LC state localized on the chelate backbone or the involvement of MLCT state in the lowest energy electronic transition. / Thesis (Ph.D, Chemistry) -- Queen's University, 2013-01-07 15:20:45.675

Dans les années 60 et avant, le marché international de l'aluminium était présenté comme un cas d'école en matière d'organisation oligopolistique des firmes. En effet, un petit nombre de grands groupes fortement intégrés (les 6 Majeurs) contrôlaient la quasi-totalité du secteur de l'aluminium, des opérations d'extraction de la bauxite, à la fabrication de produits finis à base d'aluminium, en passant par la production d'alumine et d'aluminium en lingots. A partir des années 70, ce monopole est de plus en plus contesté, notamment par des entreprises sur-liquides venues principalement des secteurs miniers et par des entreprises étatiques porteuses de motivations différentes. La création en décembre 1978 du contrat Aluminium au London Metal Exchange (LME) sonne le glas du monopole constitué par les 6 Majeurs. On passe alors d'un système de prix- producteurs, à un véritable système de prix de marché L'objectif de cette thèse est de vérifier, si le LME, bourse pionnière et marché de référence pour les métaux non-ferreux, remplit efficacement ses fonctions financières concernant l'aluminium : Information sur les prix et l'état du marché, protection contractuelle contre les risques de fluctuations des prix, stabilisation des cours.

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Electrochemical Ion Exchange (EIX) was studied to determine the viability of the process for treatment of metal bearing effluents containing Cu, Zn and Ni. Other metals used during the investigation were Na and Cs. The EIX process was examined at the laboratory scale and later in a pilot plant. Process performance and cell design were evaluated both in absorption and regeneration cycles. A mathematical representation of the system was developed based on the Nemst-Planck equation. Zirconium phosphate, Purolite S930 , Purolite S950 and Purolite PrAOH were the ion exchangers used during the study. The EIX cell was made of two perspex blocks, each 490 mm by 125 mm and 20 mm thick. Each block contained a half cell made up of an EIX electrode and a counter electrode on either side of a heterogeneous ion exchange membrane with dimensions of 280 mm by 63 mrn by 5 mm. The EIX electrode consisted of a platinised titanium mesh, acting as a current feeder, embedded in the membrane. The counter electrode was a platinised titanium mesh placed on the opposite side to the current feeder. The process was operated by applying a potential across the membrane.

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