In this thesis the magnetic and structural properties of ultra-thin 3d transition metals films have been investigated, in particular Fe, Ni and Co films. X-ray Magnetic Circular Dichroism (XMCD) has provided element specific spin (ms ) and orbital (ml ) moments per atom by utilizing the magneto optic sum-rules. Element specific hysteresis curves have been measured by means of X-ray Resonant Magnetic Scattering (XRMS), and the local crystallographic structure has been investigated using Extended X-ray Absorption Fine Structure (EXAFS). By performing XMCD on Fe/Ag(100) we observe a spin reorientation from in-plane to out-of-plane as the Fe thickness is lowered. At temperatures below 300K it occurs around 5-7 mono layers (ML) of Fe. While reorienting the magnetization out-of-plane the orbital moment increases with 125% but only a minor increase (5%) of the spin moment is observed. Extended X-ray Absorption Fine Structure (EXAFS) measurements indicate that films 6 ML and thicker have a bulk-like bcc structure. For the thin out-of-plane films, the local crystallographic structure is more complicated. The spin reorientation of the Au/Co/Au tri-layer system has been studied as a function of temperature, Co layer and Au cap thickness. An unexpected behavior of the orbital moment upon spin reorientation is found in these systems. An ex-situ prepared sample shows a smooth spin reorientation from an in-plane to an out-of-plane easy magnetization direction as the temperature is lowered from 300K to 200K. In-situ prepared samples have also been investigated and a novel phase diagram has been identified. The Au/Co interface has been explored during the Au capping by means of photoemission measurements. In the bi- and tri-layer system of Fe and Ni we have been able to manipulate the spin reorientation by varying the Fe and Ni thickness. A novel non-collinear interlayer exchange interaction for 3d ferro magnets in direct contact has been discovered for a set of samples. This exchange interaction is found to be strongly dependant on the preparation conditions.

The Bird River sill (BRS) is composed of layered mafic-ultramafic intrusive bodies which intruded the Bird River greenstone belt in southeastern Manitoba. Layered intrusions, such as those that collectively make-up the BRS, are important hosts to base and precious metal deposits. This study was initiated to examine and develop an emplacement model for the western half of the BRS and to establish the controls on Cr-Ni-Cu-PGE mineralization. The BRS intrusions were emplaced through multiple-magmatic injections into different stratigraphic levels in the Lamprey Falls Formation. It is interpreted that the central BRS intrusions are connected and represent a single conduit system. The BRS and the Lamprey Falls Formation are overlain by the metasedimentary rocks of the Peterson Creek Formation and are overturned. The stratigraphy of the BRS is divided into four series which are from the base upwards: 1) marginal mafic series, 2) ultramafic series, 3) transition series, and 4) mafic series. All significant concentrations of Cr-Ni-Cu-PGE are contained in the ultramafic series. Mineralization is magmatic in origin with significant Ni-Cu and PGE remobilization associated with late felsic magmatism. Ni-Cu remobilization is also associated with mineralized shear zones that cross-cut the BRS and Lamprey Falls Formation. The sulphur source could not be determined unambiguously based on sulphur isotopes alone but the δ34S values of the BRS intrusions suggests that the sulphur in the BRS is magmatic in origin and that two of the BRS bodies may have assimilated external sulphur. The findings of this investigation have considerable economic implications. The model that each BRS body is an individual intrusion implies each body may contain its own style of mineralization. Secondly, the Page body of the BRS is interpreted to represent a turbulent magmatic environment and to be the first intrusion to form at the lowest stratigraphic level. The magmas that formed the stratigraphically higher BRS intrusions are believed to have passed through the Page intrusion. Therefore, the Page body is an excellent exploration target as it represents a turbulent environment in which significant amounts of primitive magma have passed through which are two key factors in the formation of Ni-Cu-PGE deposits.

Abstract The Copper Catalyzed Azide-Alkyne Cycloaddition (CuAAC) is a paradigm of ¡§click¡¨ chemistry which has been applied in different fields. To understand the interaction between organic azides and a copper surface, we use benzyl azide (Bn¡ÐN£\¡ÐN£]¡ÝN£^) as an adsorbate on Cu(111) under ultrahigh vacuum conditions. The thermal reaction process was explored by a combination of temperature-programmed desorption (TPD), reflection absorption infrared spectroscopy (RAIRS), and X-ray photoemission spectroscopy (XPS) techniques. The TPD profiles show a multilayer desorption peak at 190K, two peaks for N2 , and H2 from 270K to 390K. At 345K, peak of desorption product (m/z=103) represents phenyl cyanide (PhCN) or phenyl isocyanide (PhNC). RAIR and XP spectra demonstrate that at 190K benzyl azide on Cu(111) readily adopt the imine intermediate formalism involving N£\¡ÐN£] scission and phenyl group shift from carbon to nitrogen. The mechanism is analogous to the organic reaction of Schmidt rearrangement. To heat the surface to 250K, the CH2 group of the imine intermediate undergoes C¡ÐH bond scission to produce a surface isocyanide intermediate, (M=C=N¡ÐPh). Therefore the final desorption product is phenyl isocyanide at ~350K. Intriguingly, the thermal chemistry of benzyl azide involves both imine and isocyanide intermediacy, despite the fact that azido species usually generate nitrene or imido complexes under thermal conditions.

In this study, the mechanical properties of Cu-Zr binary bulk metallic glasses (BMG) were investigated at the nano-scale. The stable amorphous structures and corresponding energies of BMG structures are performed by density functional theory (DFT) calculation as reference data. This study will combine the Force-Matching (FM) method and Basin-Hopping (BH) method to develop a new method for fitting the Cu-Zr Tight-binding (TB) potential parameters. Moreover, the Bulk modulus, Shear modulus, Young's modulus and Poisson ratio of Cu46Zr54, Cu50Zr50 and Cu64Zr36 structures are calculated with the fitting TB parameters. In addition, the compression process of BMG materials is simulated by the Molecular Statics. The stress and strain are obtained to investigate the deformation mechanism of CuZr/Zr/CuZr nanolaminates at 0 and 45 inclined degree. Finally, we investigate the angle in the deformation process under different strain in the shear band, shear transformation zones (STZs) and force caused by the slip of the atomic distribution of TFMGs layer.

In this research, a method for site-selective attachment of synthetic molecules into glycoproteins using Boronic acid (BA)-directed tosyl chemistry is proposed. The synthetic BA-tosyl chemical probes are composed of boronic asid as a affinity ligand, a tosyl group as a reactive group and a terminal alkyne group for reporting. In neutral and alkaline environment, boronic acid can act as a targeting head to react with the cis-diol of carbohydrates and therefore forms a covalently reversible boronic diester ring. The newly formed boronate ring can withdraw the probe moeular close to the molecular surface of glycoproteins of interest. Followed by a SN2 reaction with the nucleophilic residues of labeled glycoproteins, the report alkyne group can covalently shift to the protein surface apart from the BA-tosyl skeleton. With the competition of polyols, the BA modified carbohydrates can be recovered to the native glycan structures. The traceless labeling strategy developed in the work has been demonstrated in the specific interaction with a known glycoprotein feutin with negatives controls. We believe that the successful development of this methodology can certainly accelerate the study of glycoproteomics and glycobiology.

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In the present study / the effects of the powder metallurgical parameters such as the mixing method, compaction pressure, initial tungsten (W) particle size, composition, sintering temperature and sintering time on the sintering behavior of selected high density W-Ni-Cu alloys were investigated. The alloys were produced through conventional powder metallurgy route of mixing, cold compaction and sintering. The total solute (Ni-Cu) content in the produced alloys was kept constant at 10 wt%, while the copper concentration of the solutes was varied from 2.5 wt% to 10 wt%. Mainly liquid phase sintering method was applied in the production of the alloys. The results of the study were based on the density measurements, microstructural characterizations including optical and scanning electron microscopy and mechanical characterizations including hardness measurements. The results showed that the nature of the mixing method applied in the preparation of the powder mixtures has a considerable effect on the final sintered state of W-Ni-Cu alloys. Within the experimental limits of the study, the compaction v pressure and initial W particle size did not seem to affect the densification behavior. It was found that the sintering behavior of W-Ni-Cu alloys investigated in this study was essentially dominated by the Ni content in the alloy and the sintering temperature. A high degree of densification was observed in these alloys with an increase in the Ni content and sintering temperature which was suggested to be due to an increase in the solubility and diffusivity of W in the binder matrix phase with an increase in these parameters, leading to an increase in the overall sintering kinetics. Based on the results obtained in the present study, a model explaining the kinetics of the diffusional processes governing the densification and coarsening behavior of W-Ni-Cu alloys was proposed.