Thesis (M.S.)--University of Nevada, Reno, 2008. / "December, 2008." Includes bibliographical references. Online version available on the World Wide Web.

Thesis (Ph. D.)--University of Maryland, 1998. / Includes bibliographical references.

Thesis (Ph.D.)--Duquesne University, 2004. / Title from document title page. Abstract included in electronic submission form. Includes bibliographical references and abstract.

The biological half-life of inorganic mercury in the Dungeness crab, Cancer magister Dana, was determined experimentally to be about 25 days. Crabs were exposed to mercury solutions, sacrificed after varying periods of time, and mercury determinations of whole body homogenates made with an atomic absorption spectrophotometer. The simple and widely used negative exponential equation for calculating biological half-life was not entirely adequate for describing the mercury elimination process. A better description was obtained using a nonlinear least-squares fit of an equation describing elimination at different speeds from two types of tissues. A further model allowed for recycling of mercury that was eliminated, and gave marginally better descriptions in some cases. / Science, Faculty of / Zoology, Department of / Graduate

The effects of short term exposures to sublethal doses of mercuric chloride were studied using species of anadromous fish. Aspects of grou/th and behaviour u/ere used as indicators of physiological and psychological malfunctions due to mercurialism. The characteristic migration tendencies ( upstream or downstream ) of Lower Babine and Fulton River alevins were tested in experimental laboratory channels. The were conducted in a chamber in which a day, dawn through dusk, could be simulated. Each stock was divided into three groups and each group was assigned a level of treatment ( control, 0.5 ppm and 1.0 ppm HgCl₂ ). The performance of the fish in each group placed in the channels was scored. An analysis of data obtained from the migration experiments indicated that sublethal mercurialism had a disruptive influence on migration patterns of Sockeye salmon alevins. The lower level of intoxication produced a downstream drift in both stocks while the fish treated at the higher level of intoxication showed an upstream migrational tendency in both stocks. The effects of sublethal mercurialism on growth were studied using Sockeye, Chum, and Coho salmon fry. The fish received standard daily feedings. The fed fish for each of the species were divided into three treatment groups ( control, 0.5 ppm and 1.0 ppm mercuric chloride ) .Weight data were collected and analyzed using regression analysis and the analysis of covariance. The fed Sockeye and Chum salmon fry showed a significant weight loss (⍺= 0.05 ) in the 0.5 ppm and the 1.0 ppm treatments when compared to their respective controls. There was no significant difference in weight between treatments in the fed Coho salmon experiment. A six week starvation experiment was designed to test if there were any significant differences in weight loss between control fish and fish treated with 0.5 ppm and 1.0 ppm mercuric chloride. Regression analysis and the analysis of covariance did not reveal any statistically significant differences on the rates of weight loss. A flight responce experiment was conducted using Coho salmon prey and predators. Wild and hatchery Coho salmon prey were used with hatchery Coho predators. Three treatment levels of mercuric chloride were administered ( control, 0.5 ppm and 1.0 ppm ), Prey and predators were placed in an experimental laboratory performance channel and, after a timed exposure to each other, scores indicative of flight responce mere obtained. The data was analyzed using the Kolmogorov-Smirnov Large sample : one tailed test. No significant differences in the responces between treatments were noted for the hatchery Coho. The wild Coho prey treated with 0.5 ppm and 1.0 ppm mercuric chloride had a statistically significant differences when compared to their controls. It was noted that as the level of intoxication increased the the level of flight responce decreased. The results of the above experiments indicate that mercurialism has measurable effects on the physiology and psychology of fish at sublethal level. / Science, Faculty of / Zoology, Department of / Graduate

A study of the effect of photo-sensitized mercury on mixtures of isobutane and isobutene.

The problem was to study several hydrocarbons when they were subjected to ultraviolet light of 2536 Å in the presence of mercury vapor. It would be expected from the work of Stallings that the rupture of any tertiary hydrogen bond in the molecule would be the predominant effect. However, secondary and primary bond splitting would occur as well as some C-C bond rupturing, but these could be expected to a lesser degree than the first, since the t-hydrogen has the greatest reactivity.

No description available.

Recorded use of pesticides in the conservation of artifacts dates back to the 16th century. Museums today are faced with a tremendous task of identification and remediation of pesticides from artifacts in order to protect museum workers and the general public. In addition, artifacts are being repatriated by Native American tribes for use in cultural ceremonies which may subject the practitioner to health risks. Arsenic and mercury salts are among the pesticides that were used that are highly persistent and toxic. The primary challenge lies in removing these hazardous and persistent metals without damaging the materials or pigments on the objects.Concentrated aqueous alpha-lipoic acid solutions were developed for removing arsenic and mercury pesticides from materials commonly used in museum artifacts. The alpha-lipoic acid solutions were reduced using natural sunlight or laboratory ultraviolet lamps to enhance the binding of arsenic. The solubility of alpha-lipoic acid in various organic and inorganic solutions was determined and environmental parameters that impact the reduction and solubility, such as pH and temperature, were examined. The kinetics of the reaction of arsenic (III) with reduced lipoic acid was examined by varying the reduced lipoic acid, base and arsenic concentration as well as temperature and stirring conditions. The results indicated that the reaction occurs at a moderate rate primarily within 8 seconds in air. The reaction is chemically rate limited enhanced at higher temperatures and lower pH. Aerobic conditions significantly decreased the extent of the reaction with increased stirring rate. This impact was minimized by using a nitrogen environment or by limiting agitation during the reaction step.The methods developed were capable of removing up to 1000 µg/cm2 arsenic (of sodium arsenite) from simulated artifacts to levels near the lower detection limit of the X-ray Fluorescence Spectrometer (1 µg/cm2) without leaving detectable residues according to Attenuated Total-Reflection Fourier Transform Infrared Spectroscopy. Similar results were achieved in removing mercury (of mercuric chloride) from non-sulfur containing materials; however, the solutions and processes developed were not capable of removing mercury from sulfur-containing materials such as wool and feathers.

No description available.