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The purpose of this dissertation is to investigate the thermodynamic properties of nonelectrolyte solutes dissolved in ternary solvent mixtures, and to develop mathematical expressions for predicting and describing that behavior in the solvent mixtures. Thirty-four ternary solvent systems were studied containing either alcohol (1-propanol, 2-propanol, 1-butanol, and 2-butanol), alkane (cyclohexane, heptane, and 2,2,4-trimethylpentane) or alkoxyalcohol (2-ethoxyethanol and 2-butoxyethanol) cosolvents. Approximately 2500 experimental measurements were performed. Expressions were derived from the Combined Nearly Ideal Multiple Solvent (NIMS)/Redlich-Kister, the Combined Nearly Ideal Multiple Solvent (NIMS)/Bertrand, Acree and Burchfield (BAB) and the Modified Wilson models for predicting solute solubility in ternary solvent (or even higher multicomponent) mixtures based upon the model constants calculated from solubility data in sub-binary solvents. Average percent deviation between predicted and observed values were less than 2%, documenting that these models provide a fairly accurate description of the thermodynamic properties of nonelectrolyte solutions. Moreover, the models can be used for solubility prediction in solvent mixtures in order to find the optimum solvent composition for solubilization or desolubilization of a solute. From a computational standpoint, the Combined Nearly Ideal Multiple Solvent/Redlich-Kister equation is preferred because the needed model constants can be calculated with a simple linear regressional analysis. Model constants for the Modified Wilson equation had to be calculated using a reiterative trial-and-error method. The C++ program for the Modified Wilson equation applied to ternary and heptanary solvent mixtures is attached.

Zhong, Yangliu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 50-57). / Abstracts in English and Chinese. / Title Page --- p.i / Thesis Committee --- p.ii / Abstract (English Version) --- p.iv / Abstract (Chinese Version) --- p.V / Acknowledgement --- p.vi / Table of Contents --- p.viii / List of Tables --- p.X / List of Figures --- p.xii / List of Abbreviations and Symbols --- p.xiii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- DNA methylation --- p.1 / Chapter 1.2 --- Repair of m3T --- p.2 / Chapter 1.3 --- Objectives of this work --- p.3 / Chapter 1.4 --- DNA structure --- p.3 / Chapter 1.4.1 --- Nomenclature scheme for DNA --- p.3 / Chapter 1.4.2 --- Base pair scheme --- p.4 / Chapter 1.4.3 --- Sugar conformation --- p.5 / Chapter 1.4.4 --- Backbone conformation --- p.7 / Chapter 2 --- Materials and Methods --- p.9 / Chapter 2.1 --- Sample design --- p.9 / Chapter 2.2 --- Sample preparation --- p.10 / Chapter 2.3 --- NMR analysis --- p.10 / Chapter 2.3.1 --- Resonance assignment --- p.12 / Chapter 2.3.2 --- Determination of sugar conformation --- p.13 / Chapter 2.3.3 --- Determination of backbone conformation --- p.14 / Chapter 2.4 --- UV melting study --- p.15 / Chapter 3 --- Effect of m3T on Double-Helical Structures and Stabilities --- p.17 / Chapter 3.1 --- Resonance assignments --- p.17 / Chapter 3.2 --- Effect of m3T on double-helical DNA structures --- p.19 / Chapter 3.2.1 --- Base pairing mode --- p.19 / Chapter 3.2.2 --- Sugar conformation --- p.21 / Chapter 3.2.3 --- Backbone conformation --- p.22 / Chapter 3.3 --- Effect of m3T on double-helical DNA stabilities --- p.25 / Chapter 3.4 --- Discussion --- p.26 / Chapter 3.4.1 --- Single-strand requirement in FTO repair --- p.26 / Chapter 3.4.2 --- Relationship between m3T pairing structure and stability --- p.27 / Chapter 4 --- Effect of m3T Mispair on Double-Helical DNA Structures and Stabilities --- p.28 / Chapter 4.1 --- Resonance assignments --- p.28 / Chapter 4.2 --- Effect of m3T mispair on double-helical DNA structures --- p.32 / Chapter 4.2.1 --- Pairing mode of T m3T --- p.34 / Chapter 4.2.2 --- Pairing mode of G m3T --- p.35 / Chapter 4.2.3 --- Pairing mode of C.m3T --- p.35 / Chapter 4.3 --- Effect of m3T mispair on double-helical DNA stabilities --- p.36 / Chapter 4.4 --- Discussion --- p.36 / Chapter 4.4.1 --- Predominant mutation --- p.37 / Chapter 4.4.2 --- Relationship between m3T pairing structure and stabilities --- p.37 / Chapter 5 --- Conclusion and Future Work --- p.39 / Chapter Appendix I --- Proton chemical shift values (ppm) of AmT --- p.40 / Chapter Appendix II --- Proton chemical shift values (ppm) of RefAT --- p.41 / Chapter Appendix III --- Proton chemical shift values of NmT samples --- p.42 / Chapter Appendix IV --- "Σ1' and %S of TmT, GmT and CmT" --- p.45 / Chapter Appendix V --- "1H-31P HSQC spectra of (a) TmT, (b) GmT and (c) CmT" --- p.46 / Chapter Appendix VI --- "1H-31P COSY spectra of (a) TmT, (b) GmT and (c) CmT" --- p.47 / Chapter Appendix VII --- "31P chemical shifts, 3JH3'P and %Bi of TmT, GmT and CmT" --- p.48 / Chapter Appendix VIII --- "UV melting curves of RefAT, AmT, TmT, GmT and CmT" --- p.49 / References --- p.50

Since the need of energy conservation has become more and more urgent in the past decades, there has been an increased interest in the study and development of more efficient energy conversion systems. One of the fields that have arisen from that endeavor is a branch of physics called Finite Time Thermodynamics (FIT). It may be said that FIT was initiated through the famous paper by Curzon and Ahlborn (1975) that established new bounds on the efficiency of a finite time Carnot heat engine. Before, the traditional treatments gave a fundamental upper limit on the efficiency of any heat engine. However, this figure, the well-known Carnot efficiency, is far too optimistic in comparison to real heat engines. The reason lies in the fact that the traditional Carnot engine is operating infinitely slowly, thus having zero power output. Curzon and Ahlborn were able to improve upon this treatment and to set an upper limit on engines producing finite power.

There are a number of impurity elements present in sulphide ores that can have a deleterious effect on the properties of the final copper metal product. In this thesis, an equilibrium distribution technique was used to determine the thermodynamic behaviour of selenium and tellurium in molten slags used in copper production. Calcium ferrite based slags and copper or silver alloy were equilibrated in magnesia crucibles at temperatures of 1200 to 1400 °C and oxygen partial pressures of 10-11 to 10-0.68 atm. Under conditions typical of those employed during copper converting, the minor elements were found to enter the slag as negatively charged species. The partitioning of selenium and tellurium to the slag was greatest at high temperature, low oxygen partial pressure and at highest concentration of basic oxide (CaO or BaO). The experimentally derived data were combined with published information to calculate the selenide and telluride capacities of the slag, and also to generate fundamental thermodynamic activity data for selenium and tellurium in the slag phase. It was found that the activity coefficients of selenium and tellurium were independent of their concentration in the slag over the range studied, but were strongly dependent on the temperature, slag chemistry and oxidation state of the slag. Experiments were also designed and carried out to determine what effect the presence of iron oxide and its oxidation state has on the behaviour of selenium in the slag. A series of experiments involving iron oxide additions to a calcium aluminate slag was conducted under increasingly oxidising conditions to assess the effect of total iron on the selenide capacity as the dominant oxidation state of iron in the slag changed. It was shown that at a constant ratio of CaO:Al2O3, the selenide capacity increased with total iron in the slag. However, the effect on the selenide capacity did not appear any more significant as the Fe3+:Fe2+ ratio changed in a particular direction. 4 Another series of experiments was carried out with iron calcium silicate slags to determine the stability of phases within the slag, and how this affected the equilibrium distribution and activity coefficient of selenium in the slag. A number of solid phases were identified and their composition determined by scanning electron microscopy, energy dispersive spectroscopy and electron microprobe analysis. The composition and minor element content of the remaining liquid was calculated using a thermodynamic model. From this it was found that the capacity of the liquid slag has a region of independence against slag chemistry, before increasing strongly with increasing lime content to the calcium ferrite composition. Some of the implications of this work are discussed with reference to the practicality of adjusting the process variables in a large-scale industrial process for the purpose of managing minor element content of the molten phases. Considerations include the effect on copper recovery and rate of wear of furnace refractory materials.

In this dissertation, we studied the generation of squeezed states induced by a timedependent interaction and the in uence of temperature on the strength of the squeezing in a condensed matter model. The model studied comprised two quantum harmonic oscillators, with a time-dependent, non-linear coupling between them. The in uence of the thermal bath on the non-equilibrium dynamics of the model was represented in terms of non-Hamiltonian thermostats and a collection of independent harmonic oscillators with Ohmic spectral density. The equations of motion were studied in the Wigner representation, which introduces a phase space description for the model. The representation of the system in quantum phase space allowed us to investigate the di erence between purely classical evolution and the relative importance of quantum corrections with respect to the dynamics. The dynamics was studied by means of computer simulation techniques. The numerical simulation of the non-equilibrium statistical mechanics of both time-dependent and non-linear interactions allowed us to investigate conditions beyond those in recent literature [1, 2]. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.

In this thesis, applicable data from research on IC engines have been adapted to PACE engine designs. Data from studies on heat transfer, friction, and pressure losses, in particular, have been used. Certain parameters which define operation and design characteristics appear to influence PACE engine performance very strongly. Some of the more critical parameters, notably friction and heat transfer coefficients, must be determined experimentally if accurate model results are to be expected. Pressure ratio, compressor RPM, and maximum combustor temperature, the independent operating parameters, also have a dramatic effect on engine performance. Other design or operating characteristics and working fluid properties are not controlled independently. These are dictated by the engine physical design configuration and operation, ambient conditions, and choice of fuel.

Intrinsic Quantum Thermodynamics (IQT) is a theory that combines Thermodynamics and Quantum Mechanics into a single theory and asserts that irreversibility and the increase of entropy has its origin at the fundamental, atomistic level. The merits and details of IQT are discussed and compared with the well-known theory of Quantum Statistical Mechanics (QSM) and the more recent development of Quantum Thermodynamics (QT). IQT is then used to model in 3D the time evolution of the adsorption of hydrogen on a single-walled carbon nanotube. The initial state of the hydrogen molecules is far from stable equilibrium and over time the system relaxes to a state of stable equilibrium with the hydrogen near the walls of the carbon nanotube. The details of the model are presented, which include the construction of the energy eigenlevels for the system, the treatment of the interactions between the hydrogen and the nanotube along with the interactions of the hydrogen molecules with each other, and the solution of the IQT equation of motion as well as approximation methods that are developed to deal with extremely large numbers of energy eigenlevels. In addition, a new extension to the theory of IQT is proposed for modeling systems that undergo heat interactions with a heat reservoir. The formulation of a new heat interaction operator is discussed, implemented, tested, and compared with a previous version extant in the literature. IQT theory is then further extended to encompass simple mass interactions with a mass reservoir. The formulation, implementation, and testing of the mass interaction operator is also discussed in detail. Finally, IQT is used to model the results of two experiments found in the literature. The first experiment deals with the spin relaxation of rubidium atoms and the second tests the relaxation behavior of single trapped ion that is allowed to interact with an external heat reservoir. Good agreement between experiment and the model predictions is found. / Ph. D.