Engineering Commons^™

Determination Of Trace Quantities Of Selenium And Arsenic In Canned Tuna Fish Using Electroanalytical Techniques, Ann Marie Higham

Theses

Toxic metals are present in the environment and are known to be present in food. Selenium, which is considered an essential micronutrient, is recognized as a toxic metal at slightly higher concentrations. Arsenic is also recognized as a toxic metal. Selenium and Arsenic tend to accumulate in food, specifically fish and seafood.

Fifteen brands and types of tuna fish were analyzed for selenium using differential pulse cathodic stripping voltammetry. The cans with the high and low concentrations of selenium were analyzed for arsenic using differential pulse polarography. Three samples with three percent recoveries and a blank were analyzed for each …

A Study Of Parameters Indicating Microbial Activity In Mixed Aerobic Cultures, William Smith

Theses

Mixed liquor suspended solids (MLSS), oxygen uptake rate (OUR) and general dehydrogenase activity, as expressed by the reduction of the electron-acceptor Dye 3-(4',5'-dimethylthiazol-2-yl)-2, 4-diphenyltetra-zolium bromide (MTT), were compared for their ability to measure microbial activity in mixed aerobic cultures. A fourth parameter, specific enzyme activity, was dropped from consideration because of the difficulty of developing a satisfactory experimental technique. Measurement of the parameters was applied to the biodegradation of phenol and o-chlorophenol by activated sludge from a municipal sewage treatment plant, and by two commercially available bacterial preparations.

MLSS, although the most commonly used of the three parameters tested, is …

Protective Laboratory Measures For The Flexible Wall Permeameter And The Atterberg Limits Tests Using Hazardous And Toxic Chemicals, Robert A. Tetla

Theses

Safety procedures for performing geotechnical testing with hazardous and toxic materials, excluding radioactive wastes, are developed for the Flexible Wall Permeameter and the Atterberg Limits Tests. The tests were evaluated in detail to determine the critical points at which the technician would be exposed to the hazardous and/or toxic permeant. It was found that the following safety measures should always be taken; 1) the apparatus and all testing should be undertaken in a sliding sash hood using the proper face velocity, 2) air monitoring using a personal dosimeter and/or a detector tube is required to assure that the concentration of …

The Kinetics And Hepatotoxicity Of Benzyl Chloride Vapor In Rats, Hari V. Rao

Theses

Male Sprague Dawley rats (250g) were exposed to benzyl chloride vapor at a concentration of 220 ppm for 6 hours. During inhalation, the blood benzyl chloride concentration increased to reach a steady state level of 9-10 ug/ml between 4 and 6 hours of exposure. A small concentration of benzyl chloride (0.86 ug/ml) was present in the blood four hours after the termination of exposure. The absorption half life was 0.53 hours (0.39-0.81) and the elimination half life was l.12 hour (0.93-l.40).

The absorbed benzyl chloride was largely retained in the blood and some of it (0.22 ug/g) was sequestered into …

Scheduling Effects Of 5-(3,3-Dimethyl-1-Triazeno)Imidazole-4-Carboxamide (Dtic) And 1,3-Bis-Chloroethyl-1-Nitrosourea (Bcnu) On Mouse Melanoma Cells B16cl5, Gracie V. Coffey

Theses

DTIC and BCNU have been demonstrated to have enhanced chemotherapeutic effects in mice bearing Bl6 mouse melanoma cells. The order of administration seems to be important in maintaining optimum effects. This was shown is a study by Hill et al. (unpublished).

In the present study, mouse melanoma cells, Bl6CL4, were treated with either DTIC or BCNU. The drug was allowed to remain on the cells for 2, 3, or 4 days. The drug-containing media were then removed, the cells were washed and fresh medium was added. The cells were incubated in an atmosphere of 5% CO2 and 95% air at …

Forecasting For Local Water Management, Douglas Alan Putnam

Dissertations and Theses

Forecast models are investigated and developed for use in local water management to aid in determining short term water requirements and availability. The forecast models include precipitation occurrence and depth using a Markov chain model, temperature and solar radiation with a multivariate autoregressive model, and streamflow with autoregressive-moving average models. The precipitation, temperature, and solar radiation forecasts are used with a soil moisture model to determine water demands. A state space approach to the Muskingum-Cunge streamflow routing technique is developed. The forecast water demands and streamflow forecasts are used as inputs to this routing model. Forecast model errors and propagation …

Transient Flow Inverse Study Calculation Of Unsaturated Permeability Of Wood, Farid Piroozmandi

Dissertations and Theses

One of the major processes in lumber industry is wood drying. This process consumes large amounts of energy and capital, and due to the length of time it takes, it acts as a governing factor in lumber production levels. Development of improvements in processes and equipment used in wood drying can be expedited through computer simulation of various drying procedures. These numerical simulations depend on the accuracy of numerical models representing wood transport properties, including functional dependency of liquid permeability through wood with respect to local saturation level. Data available in the literature mainly represent wood permeability properties at fully …

Fate Of Heavy Metals From Highway Runoff In Stormwater Management Systems, Harvey H. Harper

Retrospective Theses and Dissertations

The movement and fate of heavy metal inputs (Cd, Zn, Mn, Cu, Al, Fe, Pb, Ni and Cr) from highway runoff were investigated in a three-year study on 1.3 hectare retention facility near the Maitland Interchange on Interstate 4, north of Orlando, Florida. Physical characteristics of the retention pond and surrounding watershed were defined and field instrumentation was installed. Stormwater samples were collected over a one-year period, representing a wide range of intensities and antecedent dry periods. Stormwater characteristics were compared with average retention pond water quality to determine removal efficiencies for heavy metals within the pond. A total of …