Engineering Commons^™

Adsorption Of Organic Compounds By Microbial Biomass, Ariamalar Selvakumar

Dissertations

The adsorption of hazardous organic compounds such as phenol, 2-chlorophenol, 2-nitrophenol, chlorobenzene, and ethylbenzene onto two types of inactive microbial biomass (activated sludge and nitrifying bacteria) was studied. The adsorption isotherms could be expressed by the Freundlich adsorption isotherm and were found to be nearly linear over the range of concentrations (50 - 200 mg/1) studied. Desorption studies showed that the adsorption process was partially reversible. Heat of sorption was estimated and indicate that the biosorption process involves a physical rather than a chemical mechanism. The adsorptive capacity of biomass is about two to three orders of magnitude less than …

Gas-Phase Reactions Of Methylene Chloride And Methylene Chloride-Trichloroethylene Mixture With Methane In Tubular Flow Reactor And Atmospheric Pressure, Javad Tavakoli-Attar

Dissertations

Reactions of methylene chloride diluted in methane and Argon and a mixture of methylene chloride + trichloroethylene diluted in methane and argon are studied in three flow reactors of different surface to volume ratios 4, 10.5, and 16 mm ID , atmospheric pressure and over a temperature range of 750-1000 °C. Experiments were conducted isothermally, ±5 °C over central 80% of oven length using a three zone oven. Argon was added as a diluent in order to limit carbon (s) formation. The concentration ratios of methylene chloride/methane/argon and methylene chloride/trichloroethylene/methane/argon was held constant at 1:4:10 and 1:1:40:40 respectively, throughout the …

Reactor Design For Hazardous Waste Treatment Using A White Rot Fungus, Daewon Pak

Dissertations

Various nutrient media and reactor configurations have been explored in order to grow the white rot fungus Phanerochaete chrysosporium, induce its active enzyme, develop kinetic data for the degradation of 2-chlorophenol, and use chemical engineering analysis to design an efficient reactor.

Preliminary experiments indicated that the biodegradation rate was improved by two to three orders of magnitude when the fungus was immobilized. As a result, emphasis shifted to two types of reactor design: a packed-bed reactor employing a silica-based porous support, and a fluidized-bed reactor employing alginate beads. Both were very effective in degrading 2 chlorophenol at inlet concentrations up …

Assessment Of Autonomic Regulation Of Heart Rate Variability, Shaw-Jyh Shin

Dissertations

Complex demodulation, accompanied by the techniques of interpolation, detrending and zero-phase-shift lowpass filtering were used to examine the effect of both divisions of the autonomic nervous system (sympathetic and parasympathetic) on heart rate by analyzing the heart rate variability signal from dogs under two different classical conditionings: CS+ and CS-, which cause different dynamic pattern changes in the autonomic nervous system to regulate the heart rate.

Unlike power spectral analysis, complex demodulation gives results in the time domain and shows the variation of amplitude and phase over time at a given frequency. The variation of phase indicates the frequency deviation …

Multiyear Drought Simulation With Periodic-Stochastic Hydrologic Processes, Lankeswara Hemal Wijayaratne

Dissertations

Previous studies on multiyear droughts are often limited to the analysis of historic annual flow series. A major problem in these studies is the unavailability of long historic flow records, on which to perform the analysis. To overcome this difficulty, the present study has used synthetically generated mean annual flow series to suppliment the historic flows. For the purpose of generating flows, a general methodology was developed to propose a mathematical model based on the harmonic and stochastic analyses of the historic flow series. The main objective was to derive a large population of multiyear drought events from the generated …

Sorption And Desorption Of Organic Compounds By Flyash, Kashinath Banerjee

Dissertations

A sorbent treatment process has been developed which uses flyash as sorbent in the treatment of highly toxic and hazardous chemicals; these include: Alcohols, Aldehydes, Ketones and Aromatics. Batch, as well as dynamic, studies were performed, in different phases, during the investigation. Single and multiple solute systems were examined separately. The samples were analyzed using a Flame Ionization Detector Gas Chromatograph.

The result of this study demonstrates that isolation/ immobilization of the organic pollutants is technologically feasible by adsorbing the contaminants onto flyash. The residual carbon content of the flyash plays a very significant role during the treatment process. The …

A Feasible Direction Procedure For General Multiple Objective Optimization, Wen-Tsia Liu

Dissertations

The Feasible Direction Finding Problem (DFP) of Zoutendijk is adapted to create a general Mathematical Programming (MP) algorithm for treating optimization problems with multiple objective functions. Classically such problems are reduced to standard MP form by converting them to single objective function problems by the use of weighting functions. Unfortunately not all practical problems can be so reduced. Consider the problem of maximizing the strength of a structure. Typically there are several, or even many, failure modes. All active failure modes must be included in the optimal search in such a way that resistance to one active mode can not …