<P> The equilibrium behavior of the boundaries separating the a and y crystalline phases in the copper zinc alloy system is investigated by measuring the magnitude, the relative anisotropy and the temperature dependence of the interfacial energies. A model, consistent with the interfacial energetics, is proposed and supported by observations of misfit dislocations at the boundary. The migration kinetics of the y/β interface are determined for both dendritic and polyhedral morphologies and the atomic mechanisms of growth are inferred from the. internally faulted ordered y precipitates. </p> / Thesis / Doctor of Philosophy (PhD)

<p> Energy-budget calculations and equilibrium model estimates of evaporation from a lichen-dominated upland site in the Hudson Bay low-lands are presented. The energy budget calculations reveal that the lichen surface is relatively resistant to evaporation with an average of only 54 percent of the daily net radiation being utilized in the evaporative process. Equilibrium estimates of evaporation consistently overestimate actual evaporation by 5 and 8 percent for hourly values and daily totals respectively. A simple model, a function of the equilibrium model, is derived from a comparison of actual and equilibrium evaporation. The only inputs required for the model are net radiation, soil heat flow and screen temperatures. Tests of the model indicate that it will predict actual evaporation within 5 percent and that it can probably be applied to any high latitude surface which exhibits a relatively large resistance to evaporation.</p> / Thesis / Master of Science (MSc)

<p> Recent investigations by H. G. Thode, J. Macnamara and C. Collins have shown that the S^32/S^34 ratio in natural sulfur-containing compounds varies by as much as five percent. These wide-spread variations suggest that fractionation of the sulfur isotopes occurs in natural processes due to differences in the chemical properties of isotopic molecules. In order to determine the magnitude of the effects that could be expected, partition function ratios for isotopic molecules containing sulfur and equilibrium constants for many isotopic exchange reactions involving sulfur have been calculated by methods of statistical mechanics. The results of these calculations are discussed. </p> / Thesis / Master of Science (MSc)

<p> This thesis examines the field performance of the water balance and equilibrium evapotranspiration models, and defines the environmental conditions for which they provided accurate estimates of water loss from a corn crop in Southern Ontario.</p> <p> It is shown that the water balance model should be used only when surface runoff is measured and drainage is negligible. An error analysis indicated that soil moisture change could be estimated within 10 percent when measurements were conducted at six sites every eight days.</p> <p> The equilibrium model predicted daily evapotranspiration within 6 percent when the latent heat exchange utilized between 65 and 80 percent of the available energy, indicating that the model can be applied within temperature limits of 17° and 32°C.</p> / Thesis / Doctor of Philosophy (PhD)

Chapter 1 introduces some of the issues which are addressed in the other chapters of this dissertation. These topics include: (1) the general equilibrium incentives in the provision of public education, (2) human capital production functions in economic modeling, (3) how public education spending may impact income inequality -- both positively and negatively, (4) the effect on public education spending of changes in the college wage premium, and (5) the overall efficiency of government-supplied capital. Chapter 2 develops a public education system in which voters face general equilibrium incentives to pay taxes for education. Middle-aged voters can increase their returns to saving by increasing the aggregate amount of human capital in the economy. I find that if students differ by their ability to increase their human capital levels through schooling, then the public education policy will invest more education funds in more productive students; this perpetuates income inequality. Also, the greater the discount rate for consumption and the elasticity of education funds in the human capital production function, the more likely it is that a public system provides greater growth in the steady state than a private system. Chapter 3 studies the allocation of government spending between general tuition subsidies for college students and need-based aid which is directed solely towards students from low-income households. The way to maximize the number of students may be to provide some need-based aid. I find that government provides more aid directed to low-income students if need-based tuition subsidies are provided rather than student loan subsidies. I also look at the effects of changes in parameters, such as the cost of education and the college wage premium, on the policies. Chapter 4 investigates the returns to aggregate factors of production when labor is disaggregated by education level. I find that a model in which the error term is assumed to be state-wise heteroscedastic and autocorrelated does a better job of approximating the pattern of wages for the different education groups than other models (pooled OLS or random and fixed effects). In addition, this model suggests a significant positive elasticity for public capital. / Ph. D.

This dissertation studies two-person signaling games where the players are assumed to be Choquet expected utility maximizers a la Schmeidler (1989). The sender sends an ambiguous message to the receiver who updates his non-additive belief according to a f-Bayesian updating rule of Gilboa and Schmeidler (1993). When the types are unambiguous in the sense of Nehring (1999), the receiver's conditional preferences after updating on an ambiguous message are always of the subjective expected utility form. This property may serious limit the descriptive power of solution concepts under non-additive beliefs, and it is scrutinized with two extreme f-Bayesian updating rules, the Dempster-Shafer and the Bayes' rule. In chapter 3, the Dempster-Shafer equilibrium proposed by Eichberger and Kelsey (2004) is reappraised. Under the assumption of unambiguous types, it is shown that the Dempster-Shafer equilibrium may give rise to a separating behavior that is never supported by perfect Bayesian equilibrium. However, it does not support any additional pooling equilibrium outcome. Since the Dempster-Shafer equilibrium may support implausible behaviors as exemplified in Ryan (2002), a refinement based on coherent beliefs is suggested. In chapter 4, a variant of perfect Bayesian equilibrium, the quasi perfect Bayesian equilibrium, is proposed, and its descriptive power is investigated. It is shown that the quasi perfect Bayesian equilibrium does not support any additional separating behavior compared to perfect Bayesian equilibrium. It may support additional pooling behavior only if the receiver perceives a correlation between the types and messages. / Ph. D.

Thermal methods of high precision were used to determine the solid-liquid phase equilibria diagrams for the potassium-rubidium and the rubidium-cesium systems. Both form minima in the liquidus curves occurring at 307.00° K with 0.667 mole fraction rubidium in the potassium-rubidium system and 282.85° K with 0.530 mole fraction cesium in the rubidium-cesium system. In the potassium-rubidium system, the liquidus and solidus points are very close together, giving a very narrow temperature range for the two phase region. The freezing point minimum in the potassium-rubidium system occurs at 0.667 mole fraction rubidium, suggesting the possible formation of a KRb2 intermetallic compound.

Thermal methods were used, to determine with high precision, the solid-liquid phase equilibria diagrams for the sodium-rubidium and sodium-potassium-rubidium systems. In the sodium-rubidium system, the results differ greatly from those of earlier works, especially near the eutectic composition where differences in freezing points as large as 25°K occur. A detailed search was made for possible intermetallic compounds (especially Na2Rb). Neither slow temperature cycling in the temperature range where compound formation could occur nor extended periods of annealing just above the eutectic temperature produced any evidence for compound formation in the sodium-rubidium system. A 2:1 (sodium to rubidium) sample was subjected to 60,000 atmospheres pressure. Again, no evidence was obtained for solid compound formation. In the sodium-potassium-rubidium system, a partial phase diagram was obtained; however, there. is no evidence of the formation of NaKRb in this system.

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No description available.