Swelling of the apical ridge and anterior acrosome of motile bovine sperm was observed using differential interference contrast optics. Transmission electron microscopy indicated that the acrosomal matrix was extended into complex folds and/or projections. Outer acrosomal and plasma membrane integrity was retained. Anterior acrosomal swelling (AS) was first observed after neat-semen had been slowly cooled to 4°C and stored for 1 day. With subsequent dilution (25 X 10⁶ sperm/ml) and incubation of sperm in a Tris fructose medium at 37°C, a majority of the motile sperm had AS. Of these unique conditions, storing sperm (1500 X 10⁶ /ml) in seminal plasma (SP) at 4°C was very conducive to AS. Replacing SP with egg yolk-citrate (EYC) inhibited AS. Using a Tris buffer with 54 mM fructose as an incubation medium eliminated the necessity of storing sperm in SP provided storage in EYC at 4°C was ≥3 days. AS occurred after storage at 37 or 4°C but not at 21°C. Storing cauda epididymal sperm at 4°C with and without 30.8 mM fructose or glucose in EYC or egg yolk-Tris (EYT) media demonstrated that AS formation required the presence of either sugar. Storing cauda sperm in EYT at 4°C with 0, 3.9, 7.7, 15.4, 30.8, and 61.7 mM fructose indicated that a minimum of 7.7 mM fructose was necessary for a strong AS response. Storage media pH was measured at the end of storage. Media pH was 6.7 with 0 mM fructose and had decreased during storage to 5.7-6.0 in media giving a strong AS response. Further experimentation with cauda sperm demonstrated that storage at reduced media pH would induce AS with or without the presence of fructose. Conversely, storage at normal pH's (6.6-6.8) inhibited AS even with fructose in the media. The proportion of motile sperm with AS was estimated from wet smears initially. Evaluation of acrosomal morphology from dry smears of vitally stained sperm was developed as a means of quantifying the proportion of viable sperm with AS. This technique also allowed closer scrutiny of the acrosomal morphology of viable sperm. The physiological importance of AS is unclear. It may be a unique form of sperm deterioration or a prelude to the true acrosome reaction since AS occurs without loss of sperm viability. / Doctor of Philosophy

An examination of selected two- and three-dimensional turbulent boundary layer data sets was made to determine the consistency of these data sets with their appropriate momentum integral equations. Several turbulent boundary layer experiments were reviewed to determined which of these provided adequate data so that they could be examined using this method. The selected data sets were used to numerically integrate and compare the two sides of the appropriate momentum integral equations in an extension of the Coles' momentum integral (PL-PR) method originally derived for two-dimensional flow. The effects of small three-dimensionality in a nominally two-dimensional flow were also studied. Three-dimensionality due to converging or diverging collateral flow and converging or diverging skewed flow about a plane of symmetry was investigated. The momentum integral examination of two-dimensional and quasi two-dimensional data sets was verified to be a useful and convenient means of data set validation. Very small amounts of three dimensionality in a nominally two-dimensional flow could have large effects on and adversely affect the outcome of a momentum integral validation of the data set. Three-dimensionality of the order of magnitude of experimental uncertainty, in the form of collateral or skewed convergence/divergence of the flow at a plane of symmetry, was shown to have large adverse effects on the momentum integral validation. Investigations of arbitrary.three-dimensional flows were generally found to lack sufficient data to perform an accurate validation using this PL-PR technique extended to such flows. / Master of Science

Procedures for designing and writing a CPU self-test program are developed for microprocessors in general. Specific examples of these procedures are then provided for both a simple example processor and for the Intel 8080; fault coverage statistics are provided for the 8080 test. The self-test methodology overlaps the tests for different elements within the CPU in order to attain a very quick test suitable for periodic background testing. Generalized fault classes are defined for the CPU and methods for sensitizing and detecting these faults are detailed. General procedures and hardware requirements for self-testing the entire microcomputer system within its operating environment are discussed. Fault simulation techniques are also discussed; simulation provides feedback on the effectiveness of a self-test and allows the test to be improved for better coverage and faster execution. / Master of Science

...This handbook will not begin to cover all of the material that applies to stage management. It is intended as an introduction for the novice stage manager who will work primarily on shows with a short run, where the director is available for consultation if the show needs help. Since it is my belief that a stage manager must project a positive attitude at all times, remaining sensitive to the feelings and moods of the artists around him, I will refer to the 11 human factor 11 of stage management throughout this handbook... / Master of Fine Arts

Uniaxial tensile tests were performed on AISI 1018 steel specimens. Tests were conducted both in air and while the specimens were undergoing electrolytic hydrogen charging. Specimens with three different surface finishes were tested at various cathodic charging current densities. The tensile deformation was initiated only after the specimen was charged to at least 95% with hydrogen. The data presented in this study show that very low cathodic charging current densities result in larger ductility losses for specimens of all three surface finishes relative to specimens tested in air. Once this lower limit of cathodic-charging current density is reached the extent to which hydrogen induced damage is developed is primarily controlled by surface finish with cathodic charging current density playing a secondary role. Specifically, cathodic charging with hydrogen at any particular current density resulted in increased hydrogen induced damage with increased surface roughness. In addition, increased cathodic charging current density resulted in increased hydrogen induced damage within any set of specimens with a given surface roughness. Hydrogen induced damage caused the reduction in area at fracture to decrease and the extent of this damage increased as the surface roughness and the cathodic charging current density increased. The strain-to-initiate cracking decreased with increased surface roughness. Elongation to fracture was shown to be a poor measure of hydrogen induced damage and crack nucleation was shown to be easier than crack propagation. Charging of specimens to at least 95% saturation at a cathodic charging current density of 375 mA/cm² did not alter the primary fracture mode. Microvoid coalescence remained dominant although there was some evidence of quasicleavage in surface cracks. These data do not exclusively support any of the currently proposed mechanisms for hydrogen embrittlement. / Master of Science

Hydrogen transport during a test and hydrogen segregation to twins, second phase particles and precipitation products prior to testing are shown to adversely effect the mechanical properties of metals. Hydrogen embrittlement processes in austenitic stainless steel, mild steel and aluminum occurred primarily by hydrogen induced weakening of the interfaces associated with specific metallographic features. In impact and slow bend tests of 21-6-9 and 304L stainless steels, the effect of hydrogen manifests itself in hydrogen induced faceted fracture along interfaces in the metal lattice. The extent of this weakening increases as the hydrogen content in the test sample is increased and during slow strain rate studies which promote hydrogen redistribution during the test. Disk rupture studies with 1015 and 1018 steels show that hydrogen segregation to the inclusion-matrix interface weakens the interface to such a degree that rapid fracture occurs. Studies with aluminum also indicate that hydrogen segregation to an interface degrades the mechanical properties. In age hardening experiments, hydrogen segregation caused an increase in the overaging kinetics in 2024 Al. This caused local softening of the aluminum and was probably due to the effect of hydrogen in promoting a loss of coherency at precipitate-matrix interfaces. The combined results of these tests support a decohesion type embrittlement mechanism, with the decohesion occurring at the interfaces. The results also suggest that any decohesion type mechanism must take into account the importance of hydrogen segregation and dislocation transport of hydrogen in the embrittlement process. / Master of Science

Fuel stocks today contain a large percentage of sulfur, nitrogen, and metals. To meet processing and environmental regulations, these components must be removed. Hydrodesulfurization reactions and the use of catalysts to enhance this process have been under extensive study in recent years. The main hydrodesulfurization catalyst used has been cobalt-molybdenum on an alumina support. This study investigated rhodium incorporated zeolites as catalysts for thiophene hydrodesulfurization reactions. The compounds RhCl₃ • 3H₂O, Rh₂(CO₂CH₃)₄, and Rh(PPh₃)₃Cl were adsorbed onto 13X and ZSM5 zeolites. Results of thiophene hydrodesulfurization over RhCl₃-13X and RhCl₃-ZSM5 were compared to those of commercial Co-Mo/Al₂O₃ to determine the most active catalyst under different experimental conditions. X-ray photoelectron spectroscopy, infrared spectroscopy, x-ray diffraction and microelectrophoresis were used to characterize the zeolites. Hydrodesulfurization reactions were carried out in a pulse microreactor/gas chromatograph system as a function of gas flow rate and reaction temperature. Reaction products were identified by mass spectrometry. RhCl₃-13X exhibited maximum thiophene conversion when presulfided with thiophene injections at 100°C, or with a 10 vol% H₂S/90 vol% H₂ gas mixture at 400°C. At a H₂S-sulfiding temperature of 250°C, the commercial Co-Mo/Al₂O₃ catalyst was most active. Over all catalysts, the only reaction products were hydrogen sulfide, butene and butane. The butene/butane product ratio increased with increasing temperature. On the basis of these results and XPS measurements, Rh(I) was identified as the active hydrodesulfurization species. / Master of Science

The initial portion of this thesis examines the problem of tracking a maneuvering target in the 2-dimensional (X,Z) plane, vertical to the ocean floor, using passive time-delay measurements. The target is free to maneuver in velocity and make depth changes at times unknown to the observer. In the past, tracking systems have used Extended Kalman Filters to process the nonlinear measurements, but these have inherent divergence problems. To overcome this, a nonlinear prefilter is added to linearize the measurements and thus allow the use of a conventional Kalman Filter which makes the tracking system more 'robust' and also decouples the depth estimator from the polar range estimator. The depth estimator is discussed in detail here. The latter part of this thesis introduces tracking in the 2-dimensional horizontal (X, Y) plane, parallel to the ocean floor, to observe polar range and target bearing angle. The approach of using a nonlinear prefilter and a standard Kalman Filter is similar to the one described above. Subsequently, the analysis is extended to a Kalman Filter which is not 'matched', i.e. it does not possess any knowledge of the deterministic inputs which cause target motion. This necessitates the use of a bank of Kalman Filters and an adaptive weighting scheme. Test results are included to show that all source maneuvers can be tracked with a relatively high degree of accuracy. / Master of Science

Clean laboratory technology and pure culture techniques were combined to determine the effect of ectomycorrhizae on the uptake of lead by Pinus sylvestris L. seedlings. By culturing the ectomycorrhizal fungus, Pisolithus tinctorius (Pers.) Coker and Couch, in liquid Hagem's medium with different concentrations of lead (0, 50, 250 and 500 ng/g sol), it was determined that the fungus readily takes up lead from such and aqueous medium. It was also determined that the pH of the medium controls the amount of lead in solution that can be taken up by the fungus. A series of growth studies where Pisolithus was cultured on Hagem's agar indicated that the growth of the fungus is reduced when the lead concentration in the medium is approximately 25 ug/g sol. It was estimated that a lead concentration of approximately 1,000 ug/g sol may completely inhibit the growth of the fungus. Furthermore, it was determined that the acetate ion is inhibitory to the growth of Pisolithus. By culturing mycorrhizal and non-mycorrhizal seedlings of P. sylvestris and analyzing the seedlings' roots, stems and leaves for their lead concentrations, it was determined that ectomycorrhizae facilitate the uptake of lead. Ectomycorrhizal roots can take up more lead from a vermiculite/hydroponic solution mixture because of their greater surface area and exploration of vermiculite surfaces as well as their increased production of lead solubilizing acids. This additional lead found in mycorrhizal roots, however, does not appear to be translocated to the above ground portions of the seedlings. This increased uptake of lead by mycorrhizal roots is expected to take place in natural soil systems as well. / Master of Science

The flotation of chalcopyrite and sphalerite has been accomplished without the use of collectors. Of the six chalcopyrite ores tested in the present work, some floated well using only a frother, while others required the addition of sodium sulfide, presumably to remove the hydrophilic surface oxidation products. On the other hand, the flotation of sphalerite ores was found to require both sodium sulfide treatment and copper-activation. The ratio of these two reagents was most critical, the optimum Cu²⁺/S²⁻ atomic ratio being approximately 0.17 over a wide range of reagent dosages. Potential measurements taken during both batch and micro-flotation experiments demonstrated that the collectorless flotation of chalcopyrite was possible only in oxidizing conditions, which confirms an earlier finding by Heyes and Trahar (1977). In relation to this phenomenon, three possible mechanisms have been discussed: i) elemental sulfur formed under oxidizing conditions is responsible for the collectorless flotation, ii) polysulfide ions formed during the incipient surface oxidation process render the mineral hydrophobic, and iii) HS⁻ ions, which may render the mineral hydrophilic upon adsorption, are removed from the system under oxidizing conditions. The first mechanism may operate primarily in acidic solutions, while the second mechanism operates in alkaline solutions where elemental sulfur is thermodynamically unstable. The third mechanism is based on the assumption that a clean, unoxidized surface is inherently hydrophobic. Spectroscopic evidence has been presented to support these proposed mechanisms. / Master of Science