The isothermal, endothermic, stepwise decomposition of ammonium metavanadate (AMV) in inert (argon or nitrogen), oxidising (air or oxygen) and reducing (ammonia) atmospheres as well as under high vacuum (pressure < IOn bar) conditions has been investigated. The reverse reaction, the isothermal recombination of V₂ 0₅ with ammonia and water vapour has also been investigated. The decomposition and recombination reactions were followed by continuously recording the mass loss of the sample with time using a Cahn R.G. Automatic Electrobalance. This enabled small samples ( ~ lOmg) to be used and consequently any self cooling of the sample during the decomposition was minimized. The intermediates and final products formed have been characterized by chemical analysis, X-ray powder diffraction studies, infrared spectroscopy and the mass loss involved in their formation. The changes in the physical properties of the samples during decomposition and recombination have been investigated by surface area measurements (using the BET method and krypton adsorption) and eIectron microscopy. Values for the enthalpy changes involved in the decomposition have been obtained by differential scanning calorimetry. The stoichiometry of the isothermal decomposition of ammonium metavanadate, under the various conditions of surrounding atmosphere has been discussed. Except for the later stages of the decomposition in ammonia, the results correspond well to the gradual reduction of the ratio of "(NH₄)₂ 0" to "V₂0₅" units from the original 1:1 ratio in ammonium metavanadate to pure "V₂0₅" with ammonia and water being evolved throughout the decomposition in the mole ratio of 2:1. The final product of the decomposition in vacuum, argon and air is "V₂0₅" and in ammonia, below 360°, V0₂. The kinetic parameters for each of the stages of the decomposition of AMV in each of the atmospheres studied have been determined. The mechanism of the first stage of the decomposition under the different conditions of surrounding atmosphere has been discussed from both the kinetic and the thermodynamic points of view. The absolute reaction rate theory has been applied to the decomposition in inert atmospheres enabling the formulae of the activated complexes formed during each stage to be calculated. It has also been shown that the detailed atomic movements occurring during the first stage of the decomposition in ammonia can be predicted from a knowledge of the stoichiometry of the reaction and of the detailed crystal structures of the starting and product materials. The kinetics and mechanism of the recombination of "V₂0₅" with ammonia and water vapour to form AMV have also been discussed in detail.

The thermal decompositions of a series of amide complexes of nickel(II) chloride have been studied. Thermochemical, kinetic, structure and solid-state stability correlations have been investigated. Complexes containing homologous amide ligands (L) of the form NiLCℓ₂, Ni₃L₂Cℓ₆, Ni₃LCℓ₆, NiL₂Cℓ₂(2H₂0) and ML₂Cℓ₂ (where M = Ni(II), Co(II) or Cu(II)) have been prepared. Chemical analysis, spectral and thermogravimetric measurements were used to characterize the complexes and their decomposition stoichiometries. Three sets of reactions were identified as yielding stable products in a single step: (i) NiLCℓ₂ (s) → NiCℓ₂ (s) + L (g) (ii) Ni₃LCℓ₆ (s) → 3NiCℓ₂ (s) + 2L (g) (iii) Ni₃LCℓ₆ (s) → 3NiCℓ₂ (s) + L (g) Characterization of the processes in the ML₂Cℓ₂ and NiL₂Cℓ₂(2H₂0) complexes was not straightforward. Reaction enthalpies (ΔH) were determined using DSC. The orders of the reaction onset temperatures (Tc), peak temperatures (Tmax) and ΔHL values for the NiCℓ₂ system were: N-methylacetamide < acetamide < N-methylformamide, suggesting the importance of steric hindrance of the methyl-substituent groups in the amide skeleton. In the Ni₃LCℓ₆, NiL₂Cℓ₂(2H₂0) and ML₂Cℓ₂ systems no simple orders could be deduced. The Te and Tmax sequences obtained from analogous metal(II) chloride complexes indicated that the copper(II) complexes were the least stable. The kinetics of the loss of L from NiLCℓ₂ complexes were investigated using isothermal TG, non-isothermal TG and DSC measurements. The contracting geometry models described the course of the decompositions in the most satisfactory manner. Apparent activation energies ( Ea) were estimated from Arrhenius plots of rate coefficients from: (i) an approximate zero-order relationship, (ii) the contracting-area (R2) and contracting-volume (R3) equations, (iii) a new empirical (B2) expression, (iv) the half-life ( 1/t₀.₅) and (v) the characteristic feature of the rate-time curve ( 1/tmax/2 ). The non-dependence of Ea on the rate equation used supports the reliability of the kinetic parameters. Non-isothermal experiments were analyzed by the Coats-Redfern, the modified BorchardtDaniels and the Kissinger methods. Arrhenius parameters were in keeping with results from the isothermal kinetic measurements. The values of Ea obtained for the NiLCℓ₂ system increased with an increase in basicity of the amide ligands. No straightforward correlation was found between Ea and Te, Tmax, ΔHL or spectral properties.

This thesis consists of two related chapters and one unrelated chapter. The first focuses on the health of immigrants in Canada, using the most up-to-date Canadian Community Health Surveys (CCHS). I re-investigate the previously well-established Healthy Immigrant Effect (HIE)--the finding that upon arrival, immigrants are relatively healthier than the native-born population; but that this health advantage declines over the years after migration. Measures of health used in this study include self-assessed health status, the likelihood of being overweight or obese, and the incidence of various chronic conditions. The first part of this chapter replicates the heavily cited work of McDonald and Kennedy (2004) by pooling multiple years of CCHS, and estimating a model controlling for immigrants' cohorts of arrival to disentangle the true effect of years-since-migration (YSM) from the cohort effects. The second part of this chapter takes a closer look at the more recent cohorts of arrival of immigrants. Here I use a matching method to compare various measures of health between immigrants who arrived before and after the implementation of the Immigration and Refugee Protection Act (IRPA). It is important to note that this study does not make any direct link between the implementation of IRPA and the health outcomes of immigrants. It merely observes and compares the health of two different cohorts of immigrants, making no assumptions as to whether these changes are a result of IRPA. My main finding is that the initial health advantage is no longer present for more recent cohorts of immigrants to Canada, and that these recent cohorts of immigrants face higher health risks associated with being overweight or obese. The other two chapter--Chapter 2, Income Processes and Intra-household Risk Sharing, and Chapter 3, Health Shocks and Income Dynamics--deal with different aspects of modelling of labour income risk over the life cycle using the US Medical Expenditure Panel Survey (MEPS). In Chapter 2, I take advantage of MEPS's large sample size (some 40,000 households) to concentrate on estimating income risk-sharing among couples. This refers to an intra-household insurance mechanism that allows couples to diversify labour income risks; for instance, they can and dynamically coordinate labour-supply decisions in response to income shocks. Specifically, this study decomposes income volatility, distinguishing between single and couple household types, and models couples' income risk-sharing as the covariance of the husband and wife's income variance for both transitory and permanent components. I use an innovative identification strategy, assuming the invariability of market price for labour to marital status, to uncover couple-specific risk-sharing parameters by allowing the income profile of singles and non-singles to have partial common structure. I find evidence of risk-sharing between spouses in response to both transitory and permanent income shocks, suggesting that couples' earning capability might be partially insulated from the impact of transitory and permanent income risk. Chapter 3 is co-authored with two of my supervisors, C. Deri Armstrong and G. Dunbar. The work is done primarily by myself, except for the Introduction, where both co-authors contribute to the writing. G. Dunbar also contributes to parts of the sections on Heterogeneous Health Impacts and Endogeneity, and to the Conclusion. This chapter also uses MEPS data, but focuses on understanding the significance of the negative health shocks in decomposing labour income risk. As in Chapter 2, we break down the cross-sectional variance of residual earnings into transitory and permanent components. We then propose a method to decompose the heterogeneity of health shocks impacts by partitioning the cross-sectional variance of residual earnings into a health and non-health component. We use emergency room (ER) visits as a proxy for negative health shocks, and we separately consider the impact of these negative health shocks for several groups, such as single men and single women with no child, single mothers, and couples. We also probe the role of health insurance in attenuating the income effects of health shocks, and put forward a creative method to control for misspecification biases in the income regressions--the usual ability bias. Our results suggest that heterogeneity in health shocks is gender-differentiated. We find that health shocks have heterogeneous impacts for single women with no child, as well as single mothers; but no such evidence is found for single men. For couples, we find that having health insurance coverage reduces the impact of negative health shocks on income volatility by roughly 10 percentage points.

The well-separated pair decomposition (WSPD) of the complete Euclidean graph defined on points in R 2 , introduced by Callahan and Kosaraju [JACM, 42 (1): 67-90, 1995], is a technique for partitioning the edges of the complete graph based on length into a linear number of sets. Among the many different applications of WSPDs, Callahan and Kosaraju proved that the sparse subgraph that results by selecting an arbitrary edge from each set (called WSPD-spanner) is a 1 + 8/(s − 4)-spanner, where s > 4 is the separation ratio used for partitioning the edges. Although competitive local-routing strategies exist for various spanners such as Yao-graphs, Θ-graphs, and variants of Delaunay graphs, few local-routing strategies are known for any WSPD-spanner. Our main contribution is a local-routing algorithm with a near-optimal competitive routing ratio of 1 + O(1/s) on a WSPD-spanner. Specifically, using Callahan and Kosaraju’s fair split-tree, we show how to build a WSPD-spanner with spanning ratio 1 + 4/s + 4/(s − 2) which is a slight improvement over 1 + 8/(s − 4). We then present a 2-local and a 1-local routing algorithm on this spanner with competitive routing ratios of 1 + 6/(s − 2) + 4/s and 1 + 8/(s − 2) + 4/s + 8/s 2 , respectively. Moreover, we prove that there exists a point set for which our WSPD-spanner has a spanning ratio of at least 1 + 8/s, thereby proving the near-optimality of its spanning ratio and the near-optimality of the routing ratio of both our routing algorithms.

The direct anodic decomposition of copper-rich mattes using packed bed electrodes was investigated, because a practical solution to direct electrorefining of copper matte would lead to the potential elimination of copper converting and its associated sulphur dioxide emissions. Much greater copper extraction has been achieved experimentally at 50° C from a packed bed electrode consisting of 0.5-4mm diameter particles than from a massive or solid flat electrode composed of copper-rich matte, as found in earlier studies. This was shown to be attributable to natural convection mass transport processes within the inter-particle region that is not available in massive electrodes. However, while natural convection mass transfer is an important process in the packed bed electrodes, other factors were shown to be ultimately more important in terms of the maximum copper extraction which may be achieved prior to shut-down caused by total-bed polarization of these electrodes. Total-bed polarization of copper-rich mattes during direct anodic decomposition may be attributed to (a) deteriorating electrical contact (related to the formation of elemental sulphur and lead sulphate) between the current distributor and the adjacent particles, and in thick electrodes, between the particles across the anode, (b) relative nonreactivity of iron-containing phases and (c) physical association of these phases with the reactive phases, and under certain conditions (d) crystallization of copper sulphate within the inter-particle region, blocking ionic conduction paths. The maximum copper extraction from synthetic pure chalcocite, the predominant component of industrial copper-rich mattes, using the packed bed electrodes was found to be about 80%. The presence of 3-4wt% iron in the copper-rich mattes was shown to degrade the copper extraction considerably due to the presence of relatively nonreactive iron-rich phases which form as the matte is cooled from its liquid state. The presence of lead in copper matte was found to be a relatively unimportant impurity in terms of copper extraction, while oxygen was found to partially offset the negative effects of iron. A simple one-dimensional mathematical model was developed to estimate the variation of copper extraction across a 2cm-thick packed bed electrode. The copper extraction was found experimentally to vary by less than a factor of two across the anode. This was attributed to (a) the relatively high electrical conductivity of the electrolyte which minimizes reaction-process overpotential gradients across the anode, and (b) the increasing impedances of the decomposition processes in the most reacted particles. / Applied Science, Faculty of / Materials Engineering, Department of / Graduate

This thesis aims at investigate the feasibility of classifying the soprano singing voice type using a single layer neural network trained with the FIR-ELM algorithm after that the monaural auditory mixture has been segmented with the Harmonic, Percussive and Residual, HPR, decomposition algorithm, previously introduced by Driedger et al.Two different decomposition structures has been evaluated both based on the same HPR decomposition technique. Firstly one single layer that only take advantage of the result of the more pure harmonic and the more pure percussive components of the signal. Secondly, one multilayer structure that further decompose both the harmonic and the percussive components but also takes into account the components that can not be clearly categorized as neither harmonic or percussive components, these are the residual components. The result of the classification was up to 98.5 $\%$ after using these segmentation techniques, this shows that it is feasibly to classify the singing voice type soprano in an monaural source recorded in a non-professional environment using the FIR-ELM algorithm.

In this thesis, we study problems with heterogeneities using the zeroth order optimized Schwarz preconditioning. There are three main parts in this thesis. In the first part, we propose an Optimized Restricted Additive Schwarz Preconditioned Exact Newton approach (ORASPEN) for nonlinear diffusion problems, where Robin transmission conditions are used to communicate subdomain errors. We find out that for the problems with large heterogeneities, the Robin parameter has a significant impact to the convergence behavior when subdomain boundaries cut through the discontinuities. Therefore, we perform an algebraic analysis for a linear diffusion model problem with piecewise constant diffusion coefficients in the second main part. We carefully discuss two possible choices of Robin parameters on the artificial interfaces and derive asymptotic expressions of both the optimal Robin parameter and the convergence rate for each choice at the discrete level. Finally, in the third main part, we study the time-dependent nonequilibrium Richards equation, which can be used to model preferential flow in physics. We semi-discretize the problem in time, and then apply ORASPEN for the resulting elliptic problems with the Robin parameter studied in the second part.

Olefin metathesis is arguably the most versatile catalytic route yet developed for the assembly of carbon-carbon bonds. Metathesis methodologies are attractive from both synthetic and ecological standpoints, because they employ unactivated double bonds. This reduces the total number of synthetic steps, and the associated generation of chemical wastes. The drive to deploy olefin metathesis in highly demanding contexts, including pharmaceutical manufacturing and chemical biology, puts severe pressure on catalyst lifetime and productivity. Understanding the relevant decomposition pathways is critical to achieve essential performance goals, and to enable informed catalyst redesign. This thesis work expands on significant prior advances that identified and quantified critical decomposition pathways for ruthenium catalysts stabilized by N-heterocyclic carbene (NHC) ligands. Because pristine catalyst materials are essential for mechanistic study, it focuses first on methods aimed at improving efficiency and purity in catalyst synthesis. Merrifield iodide resins were shown to function as efficient, selective phosphine scavengers in the production of clean second-generation catalysts from PCy3- stabilized precursors. The thesis then turns to mechanistic examination of decomposition pathways that underlie success and failure for leading NHC catalysts, for comparison with a new family of catalysts stabilized by cyclic (alkyl)(amino) carbene (CAAC) ligands. These represent the first in-depth mechanistic studies of the CAAC catalysts, which have attracted much attention for their breakthrough productivities in challenging metathesis reactions. The remarkable productivity of the CAAC catalysts is shown to originate in their resistance to decomposition of the key metallacyclobutane intermediate via b-elimination, and (to a lesser extent) in their resistance to attack by nucleophiles and Bronsted bases. Importantly, however, they are more susceptible to bimolecular decomposition. The latter behaviour, as well as their resistance to b-elimination, is traced to the strong trans influence of the CAACs relative to NHC ligands. This insight significantly advances our understanding of the fundamental properties governing both productivity and decomposition. Finally, two new catalysts are developed, building on the principle that nucleophilic stabilizing ligands should be avoided in the precatalysts. In the first of these complexes, an o-dianiline ligand is employed to stabilize the precatalyst. This flexible, H-bonding chelate serves the further purpose of accelerating macrocyclization of flexible dienes that bear polar functionalities. As its H-bonding capacity also increases its sensitivity to trace water, however, an alternative catalyst architecture was pursued. The latter consists of a dimer bearing bulky Ru-indenylidene centers, in which a dative bond from a bridging chloride affords the fifth ligand essential to stabilize the precatalyst.

Diploma thesis Effect of emergent micropolutants on the denitrification process through activated sludge is focused on three specific substances. The substances under investigation are atrazine, terbutylazine and sulfametaxazole. Atrazine and terbutylazine are pesticides, particularly herbicides. Sulfametaxazole was chosen as a common antibiotic. The thesis is summarized into 10 chapters and conclusion. The work consists essentially of theoretical and practical part. Part of the theoretical part of the thesis is legislation that deals with the matters of the problem with micropolutants. The next chapter is an introduction to the issue, where we want to familiarize the reader with the current situation. There are also chapters on emergent micropolutants, denitrification and investigated substances. If we look at the practical part, there are chapters on sampling, evaluation of BATCH tests and evaluation of inhibition tests. There are also chapters on BATCH tests and respiratory inhibition test, which describe procedures of how we performed this test. Laboratory test reports are included in the Annex.

The modern theory of phase transitions cannot explain the results of many experiments of interphase mass transfer. One reason for this is the assumption that during crystallization the solution is in the metastable state. The decomposition of the solution occurs by binodal scenario in this case. Crystallization nuclei form and grow in solution. The purpose of this study to show that in many cases the solution during crystallization is in an unstable state. The unstable condition leads to decomposition the solution by spinodal scenario.