We introduce a symbolic computational approach to detecting all permutation and parity symmetries in any general evolution equation, and to generating associated invariant polynomials, from given monomials, under the action of these symmetries. Traditionally, discrete point symmetries of differential equations are systemically found by solving complicated nonlinear systems of partial differential equations; in the presence of Lie symmetries, the process can be simplified further. Here, we show how to find parity- and permutation-type discrete symmetries purely based on algebraic calculations. Furthermore, we show that such symmetries always form groups, thereby allowing for the generation of new group-invariant conserved quantities from known conserved quantities. This work also contains an implementation of the said results in Mathematica. In addition, it includes, as a motivation for this work, an investigation of the connection between variational symmetries, described by local Lie groups, and conserved quantities in Hamiltonian systems.

No description available.

Master of Arts / Department of Communication Studies / Soo-Hye Han / At the turn of the 21st century, an ideological movement defined by many as the modesty movement helped push sexual abstinence as a controversial yet significant public issue in the United States. Concerned with a "hyper-sexualized" culture, modesty advocates urged young women to make a pledge to remain pure until marriage. Following the the growth of the movement, feminist scholars have been critical of the movement and the potentially detrimental consequences of purity pledges on young women's identity, sexuality, and sexual agency. This study takes a step back from this critical view of purity pledges and listens to young women's lived experience of making a purity pledge and living a life of purity. Specifically, this study asks how purity pledgers understand and enact purity and how they perceive their sexuality and sexual agency. To answer these questions, qualitative interviews were conducted with nine young women who at some point in their life made a purity pledge. A thematic analysis revealed three major themes: 1) living a pure life is situated within multifaceted perspectives on purity, 2) living a life of purity consists of negotiating multiple "selves," and 3) living a life of purity grants and reinforces a sense of agency. A composite description illustrates that religious messages, parents, peers, and sex education classes continue to influence their understanding of purity and sexuality. This project concludes with a discussion of theoretical implications surrounding the idea of a "crystallized self" and practical implications of this study on an organizational, familial, and personal level.

Over the last 100 Years, the cyanidation process has been the most popular method for recovering gold from its ores. Despite this, there are still efforts to improve the efficiency of the process, particularly as ores become more difficult to treat. Many investigators have studied the cyanidation process, although a large proportion of these studies have obtained contradictory results. This thesis presents a kinetic and electrochemical study of the leaching of gold in cyanide solutions, and emphasis is placed on rationalising the conflicting results which have been published in the past.The leaching rate of gold was measured using a rotating electrochemical quartz crystal microbalance, an instrument which allows the simultaneous measurement of electrochemical data and mass changes at the solid-solution interface in real time. A proportion of this project was devoted to the on-going design of this instrument, and a number of modifications are discussed in detail. Initially, the leaching of gold in cyanide solutions was investigated under conditions of high purity. Under these conditions, it was found that the gold surface is blocked by a passive film, presumably AuCN. The presence of such a film results in the reaction being chemically controlled, and under typical cyanidation conditions (4 mM cyanide, pH 10.0), the rate of dissolution is very low. These kinetic results were supported by complimentary electrochemical studies, which showed that gold is passive in the potential region where cyanidation occurs.The second part of this thesis presents a study of the effect of system purity on the leaching of gold in cyanide solutions. Solution phase purity was investigated by adding controlled amounts of lead or silver to the leach solutions. It was found that in the presence of low concentrations of lead, the dissolution of gold in 20 mM cyanide solutions was oxygen ++ / diffusion controlled (as compared to chemical control for gold in the absence of lead). However, high concentrations of lead were found to be detrimental to the leaching process. It is believed that the role of lead is to modify the surface by cementation, hence reducing the effect of the passive film. Silver was also found to be effective at reducing passivation, and the role of silver believed to be similar to that of lead. It was found that unlike lead, high concentrations of silver are not detrimental to the dissolution of gold in cyanide solutions.Solid phase purity was also found to be important in the leaching of gold, and it was found that the leaching of a gold sample which contains 1 % silver is diffusion controlled. This finding is important from an industrial viewpoint, as most native gold contains some silver. Consequently, attempts were made to rationalise the leaching of gold/silver with current plant practice. Discussion on the effect of cyanide and oxygen concentrations, temperature and lead addition is presented.

No description available.

No description available.

Thesis (Th. M.)--Westminster Theological Seminary, Philadelphia, 1994. / Typescript. Includes bibliographical references (leaves 95-98).

Thesis--Friedrich-Alexanders-Universität Erlangen, 1898. / Includes text in Arabic. Includes bibliographical references.

The impetus for this thesis came from experience in the worlds of medicine, urgent and disturbing aspects of heath and people meeting to find ways through complex problems about them. The author facilitated policy making and dialogue between people from very different backgrounds for a number of years. The thesis is an engagement with ambiguous and contradictory human reactions to stress while being-in-the-middle of threat and differences of many kinds. These trigger both scapegoating and an urge to mate. The phenomenon is embodied in the symbol and ritual of the pharmakos. The aim of the thesis is to engage with the phenomenon of the pharmakos, in order to bring back its symbolism and practice to conscious attention in dealing with many demanding situations today. / Doctor of Philosophy (PhD)

Organic light-emitting Diode (OLED) emits light itself. It owns many advantages of optical-electronic characteristics as compared with Thin Films Transistor-Liquid Crystal Display (TFT-LCD). In order to achieve the requirement for full color flat panel display, the three primary colors which are red, green, blue (R,G,B) with high luminance¡Bhigh current efficiency¡Band high color purity are important study of research and development for OLED. In our experiment, the major materials are NPB¡BDPVBi¡BAlq3¡BLiF¡BPBD¡BDCJTB¡FThe materials of NPB¡BDPVBi¡BAlq3,LiF is used as hole transporting layer¡Bblue emission layer¡Belectron transporting layer, and electron injection layer, respectively. PBD is hole-blocking layer and DCJTB is red emission layer which is intended to indirectly demonstrate the hole-blocking effect in the interface between NPB and DPVBi layer. The blue light emission with short wavelength plays an important role in color conversion method (CCM) of full color technology. In the study, we improve and research on color purity of blue OLED by various thicknesses of organic layer. In addition, we research the influence of the device with different thicknesses of PBD layer as hole-blocking layer. In order to improve the color mixing phenomenon, we add extra DPVBi layer to the device with PBD layer. It can improve the blue color purity and obtain narrower full width at half maximum (FWHM).