Chlorophenols represent a class of organic contaminants that are commonly used and widely distributed in the environment. Adsorption to soils may inhibit the transport of these chemicals, while slow desorption rates can create a potential source for long-term contamination of groundwater supplies. Microbial degradation of these compounds may also play an important role in their environmental fate. The purpose of this study was to investigate how the processes of sorption, desorption, and biodegradation interact to affect the distribution of pentachlorophenol (PCP) and 4-monochlorophenol (4-MCP) in two soils with different soil organic matter (SOM) content. Batch soil microcosms were used to measure the sorption of both test compounds at three concentrations for each, exposed to two soils with different SOM levels. An ultrafiltration study was designed to quantify partitioning to dissolved organic matter (DOM), while batch desorption experiments were performed to measure chemical release from the soils. Finally, biodegradation experiments were carried out under aerobic conditions to evaluate microbial interactions with PCP and 4-MCP in both the liquid and solid phases. Sorption of both compounds was rapid, with 60-80% occurring within one day, but the process appeared to continue at a slower rate over several months. Statistical analysis showed that there were no differences in sorption due to SOM content or chemical concentration, for the two silty loam soils used in this study. Desorption followed a similar pattern of a fast and then a slow stage, and a significant difference was measured between the two soils. Higher levels of SOM resulted in slower desorption and a lower total release of the contaminants, but both soils retained a large percentage of unextractable compounds. Contact time was found to have the greatest effect on the amount of this nondesorbable fraction. The ultrafiltration study suggested that DOM polymerized into larger molecules after sufficient mixing time (3 months) in solution, which also increased the amount of 4c compounds that were bound to these humic substances. The biodegradation study suggested that natural soil microbes could utilize PCP and 4-MCP from both the liquid and solid phases, and that sorption to dissolved organics and colloidal matter could protect these chlorophenols from microbial degradation. Some data also indicated a possible correlation between desorption rates and bioavailability. / Master of Science

Analytical and computational models for the solution of steady inviscid flows in a converging-diverging nozzle are presented for a general fluid. The main emphasis is placed on Bethe-Zel'dovich-Thompson fluids, i.e., those having specific heats so large that the fundamental derivative of gasdynamic is negative over a finite range of pressures and temperatures. Three general classes of flow are delineated which include two nonclassical types in addition to the usual classical flows; the latter are qualitatively similar to those of a perfect gas. The nonclassical flows are characterized by isentropes containing as many as three sonic points. Numerical solutions depicting finite strength expansion shocks, steady flows with shock waves standing upstream of the nozzle throat, and steady flows containing as many as three shock waves are presented. Nonclassical flows having arbitrarily large exit Mach numbers can be obtained only if a sonic expansion shock is formed in the nozzle. / Master of Science

In this thesis I argue that William H. Sheldon's somatotypes can be seen as fictional constructions. The traditional notion of idealization in prose fiction intrudes into Sheldon's reading of his somatotypes; the same kind of idealization, based on anthropological stereotyping, that had marked the science, or pseudo-science, of physiognomy. An integral aspect of physiognomy had been biological hierarchy and distinction, which had undergirded both the ancient and the European class systems, and which had provided a palpable benchmark for identifying nobility, heroism, and aristocracy. Sheldon's constitutional psychology, I argue, is a thinly disguised revolt against the falling away of this biological hegemony. The demise of heroism and "Promethean Will" or individuality was, for Sheldon, a matter of nostalgia and alienation. The somatotype studies, while fostering the illusion of detached empiricism, actually allow Sheldon to judge contemporary humanity according to antique (heroic) standards. Sheldon's somatotypes, therefore, are artifactual; to the degree that they express as much about the "temperamene" of their "author" as they do about the somatotypes themselves. In this way, Sheldon constrlcts his subjects. Sheldon's proposed program of "biological humanics", a variety of eugenics, was, in truth, an agenda (a fantasy) for recapturing the glory of the past. It was a scheme to reinvest power, beauty, heroism (primitive splendor), into the physical body; qualities and relationships which had characterized the ancient world, and which had been compromised by the "shopkeeper" and cowardly mentality of modern society. / Master of Science

A great deal of research has been conducted on the effects of vibration on visual acuity. The human contrast sensitivity function (CSF) has also been studied extensively as a predictor of visual performance under real-world conditions. However, no previous studies have combined the two lines of research and examined the effect of vibration on the CSF. Prior research indicates that increasing rates of vibration correspond to a decrease in traditional measures of visual acuity. However, other studies indicate that motion enhances target detection. The present study examined the effects of vibration upon the CSF and found that vibration lowers the threshold of detection for low spatial frequencies but raises the threshold for high spatial frequencies. A loss of contrast at high spatial frequencies due to retinal "smear" may be the cause of this increase in high spatial frequency thresholds under vibration. Physiological mechanisms of motion detection, direction selectivity, and visual pathways are also discussed. This study may have important implications for aerospace medicine and occupations which demand viewing a target or instrument panel under conditions of vibration. / Master of Science

The fault location and reconfigurable designs of Ripple Carry (RC) adders and Carry Save (CS) multipliers are studied in this thesis. The proposed designs can locate a faulty cell and reconfigure the faulty array to tolerate the faulty cell. Laser programming technique is used for fault location and reconfiguration. The key idea employed in the proposed methods is to perform diagnosis and reconfiguration at the same time. Appropriate fuses are programmed to locate a faulty cell, and the programmed fuses are also used for reconfiguration. This leads to small area overhead, and hence, substantial improvement in yield. Experimental results show that the yield enhancement of reconfigurable RC adders and CS multipliers is substantial compared with that of original RC adders and CS multipliers, respectively. / Master of Science

A novel and highly-abundant 39-kOa acidic water stress protein, Wsp, has been purified and partially characterized from cells of the desiccationtolerant cyanobacterium <i>Nostoc commune</i> (Scherer, S. and Potts, M. 1989. J. BioI. Chem. 264:12546-12553). In the original study, several inconsistencies were noted and are addressed in this body of work. Firstly, the microheterogeneity noted on two dimensional electrophoresis gels indicated the possibility of modifications of the protein or the existence of isoforms of Wsp. This possibility was not addressed in the original study. On two-dimensional gels, several proteins were seen to migrate differently in the 4.5 to 5.5 pH range. These proteins showed a similar change in staining characteristics and after 24h of rehydration a single darkly staining area was resolved. Immunocytochemical analysis revealed that a fraction of Wsp is secreted, and accumulates as a very discrete layer at and around the periphery of the envelope of both vegetative cells and heterocysts. This introduced the possibility that Wsp is a glycoprotein with a large proportion of carbohydrate to protein. However, the original study did not detect carbohydrate attached to Wsp. This was a direct result of the methodology employed to isolate the protein for characterization. A high speed centrifugation step in the protocol of Scherer and Potts (Scherer, S. and Potts, M. 1989. J. BioI. Chern. 264: 12546-12553) selected against isolation of a carbohydrate-bound protein. Further, only minimal glycosylation of this form of Wsp was detected by fluorimetric analysis and Concanavalin A binding experiments (Scherer, S. and Potts, M. 1989. J. BioI. Chem. 264:12546-12553). In the present study, it is shown that Wsp is intimately associated with carbohydrate; more specifically I the data suggest that this form of Wsp may be glycosylated. Wsp is also found to be ubiquitous in materials of <i>Nostoc commune</> collected from the Tropics to the polar regions, some after having being stored for 17 years in the air-dry state. Through the use of protease inhibitors, forms of Wsp, of significantly greater molecular mass than those seen in the primary study, were identified and characterized. This study indicates that the significant amount of Wsp present in desiccated cells is turned over rapidly and within minutes of cell rehydration. This turnover is prevented by a number of different protease inhibitors. Of these, diisopropyl fluorophosphate (DFP) affords the most efficient protection of Wsp. The glycosylation status and specific proteolysis of Wsp in <i>Nostoc</i> are discussed. / Master of Science

A lightweight floor system consisting of a concrete slab on steel joists or beams is susceptible to annoying vibrations caused by walking. This investigation considers a criterion developed by Allen (1991) that indicates whether a proposed structural floor system is acceptable for walking vibrations. The proposed vibration criterion is evaluated using the Murray vibration criterion as a basis for comparison. Both criteria are used to determine the acceptability of existing office floors, shopping malls, and pedestrian bridges. The evaluation results for each criteria are compared and the strengths and weaknesses of both criteria are discussed in detail. A derivation is presented for the proposed criterion and the calculations involved in utilizing the criterion are described. Finally, recommendations for future research are discussed based on the evaluation results of the investigation. / Master of Science

The objective of this thesis is to further investigate the base test method and to develop an analytical model which can accurately predict the failure of an uplift-loaded standing seam roof system. Four sets of full-scale tests were conducted and their results were analyzed along with previous results (Anderson 1991). It was found that by normalizing the data, a reduction factor could be established for each test set configuration. This reduction factor applies to both the base test and confirming multi-span test in each test set. Three analytical models were applied to predict the failure of the purlin. It was found that only the LaBoube Method accurately predicted the yield stress for only the simple span tests. It was determined that a variance exists in the failure loads of uplift-loaded standing seam roof systems which need to be investigated through testing. / Master of Science

Master of Architecture

The process of the architect involves the contradictory yet coexisting realms of form and order, the soul and the intellect, the nondiscursive and the literal. Meaning can be found in both worlds. The rational and linguistic manifests itself in the architectural; architecture, however, expresses ideas as art and reveals that which is verbally ineffable. / Master of Architecture