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Anaerobic Biodegradation Of Trichloroethylene By Activated Carbon Fluidized-Bed, Jiunn-Horng Chern Dec 1988

Anaerobic Biodegradation Of Trichloroethylene By Activated Carbon Fluidized-Bed, Jiunn-Horng Chern

Theses

The synthetic wastewater containing trichloroethylene (TCE) was anaerobically degraded with glucose using activated carbon fluidized-bed.

The range of TCE concentration from 26 ppb to 10.8 ppm was examined. The ratio of glucose to TCE in the influent wastewater was ranged from 26 to 805, while the TCE loading ranged from 0.025 to 1.510 mg/hr-L.

The TCE removal efficiency under these treatment conditions was found to be of 99.4%. However, the reduction of chemical oxygen demand (COD) decreased when the TCE loadings was over 0.38 mg/hr-L.


Nexus, Robert Reichhardt Nov 1988

Nexus, Robert Reichhardt

Theses

None provided.


Development Of A Novel Dentin Bonding Agent And Testing For Mechanical Properties, Mircroleakage And Toxicity, Sanjay V. Odak Sep 1988

Development Of A Novel Dentin Bonding Agent And Testing For Mechanical Properties, Mircroleakage And Toxicity, Sanjay V. Odak

Theses

In this study a dentin bonding agent based on Tolylene diisocyanatc with o chlorophenol as a blocking agent was tested. Bond strength with dentin was determined using a clinically relevant test method. A comparison was made using commercially available bonding agents and restorative resins. A simulation of microleakage around restorations was performed using a "Silver staining technique". Microleakage was quantified using digital image analysis, and a method was proposed to compensate for the loss of the third dimension during image analysis. Layer-by-layer curing of restorative, and an acid etching technique was used to improve bonding to dentin. The oral LD50 …


An Intelligent Computerized Pulse-Duplicator For The In-Vitro Evaluation Of Prosthetic Heart Valves, John F. Andrews Sep 1988

An Intelligent Computerized Pulse-Duplicator For The In-Vitro Evaluation Of Prosthetic Heart Valves, John F. Andrews

Theses

A computerized data acquisition system is presented for the in-vitro determination of the hydrodynamic performance of prosthetic heart valves. High speed data acquisition and ensemble averaging techniques are employed to minimize error and provide a standard for data collection and analysis across a wide range of simulated physiologic conditions. Processing algorithms automatically divide the cardiac cycle into phases based on landmarks in the pressure and flow waveforms, with minimal variability and without operator intervention. The contributions of valve resistance, regurgitation, ejection, leakage, and power loss to hydrodynamic performance are isolated for investigation. Phasic power loss analysis is reviewed as a …


Computerized Analysis Of Gastrointestinal Spike Burst Activity, Karthik Krishnan Sep 1988

Computerized Analysis Of Gastrointestinal Spike Burst Activity, Karthik Krishnan

Theses

This thesis describes a computer algorithm for locating gastrointestinal spike bursts. The algorithm also finds the the number of spikes within each spike burst, the average duration, and average amplitude of each spike burst. The algorithm was applied to the automation of the analysis of the Migrating Colonic Complex.

The algorithm detects the spike burst using threshold, time interval and frequency criteria. The computer program is implemented on a PDP 11/73 digital computer. The operation of the algorithm was tested on animal models to detect the spike bursts, before and after the inducement of certain drugs to alter the colonic …


A Study Of Human Exposure To Benzo(A)Pyrene (Bap) Through Different Pathways. Part A ; Assessment Of Benzo(A)Pyrene (Bap) Exposure Through Urine Analysis With The Hydriodic Acid Reduction Reaction. Part B, Shao-Keng Liang Sep 1988

A Study Of Human Exposure To Benzo(A)Pyrene (Bap) Through Different Pathways. Part A ; Assessment Of Benzo(A)Pyrene (Bap) Exposure Through Urine Analysis With The Hydriodic Acid Reduction Reaction. Part B, Shao-Keng Liang

Theses

PART A: An investigation of total human exposure to an environmental pollutant is described. The study is being conducted in a community impacted by a foundry suspected to be a dominant local source of benzo(a)pyrene (BaP). The research aims to assess the relative contributions of indoor and outdoor sources and to measure BaP in media including indoor air, outdoor air, food and water.

PART B: A method for biological monitoring of exposure to benzo(a)pyrene, a representative polycyclic aromatic hydrocarbon (PAH), has been developed. The analytical procedure includes extraction of PAH and PAH metabolites from urine using commercial cartridges containing c …


Oxidation Of Toluene, Benzene And P-Xylene In A Photoreactor, Shiey-Shiun Horng Aug 1988

Oxidation Of Toluene, Benzene And P-Xylene In A Photoreactor, Shiey-Shiun Horng

Theses

A new photoreactor was designed with stainless steel to oxidize refractory chemicals found on the EPA priority list. This new system was investigated by conducting experiments with three three model compounds, namely, toluene benzene and p-xylene. While toluene and benzene reactions are similar, they are faster with UV/ozone than UV/H2O2 and p-xylene reacts even faster with UV/ozone than UV/H2O2. The experimental data obtained were analyzed by GC and used to interpret the reaction kinetics from proposed models. The rate constants and mass transfer coefficients were found by using the Rosenbsrock Hillclimb optimization algorithm. …


Breast Cancer: Options In Care And Treatment, Elliot Friedman Aug 1988

Breast Cancer: Options In Care And Treatment, Elliot Friedman

Theses

None provided.


The Embryological Development Of The Tilapiine Fishes, Michelle Katz Aug 1988

The Embryological Development Of The Tilapiine Fishes, Michelle Katz

Theses

None provided.


Extraction Methods For Iodine From Crude Oil Systems For The Determination Of 129i/127i Ratios, Sharon Tullai Jul 1988

Extraction Methods For Iodine From Crude Oil Systems For The Determination Of 129i/127i Ratios, Sharon Tullai

Theses

129I/127I ratios were investigated as a potential for dating and tracing studies of crude oil systems. 129I/127I ratios were measured using a tandem accelerator mass spectrometer located at the University of Rochester. Carrier-free methods for AgI preparation are discussed for formation waters, petroleum, and source and reservoir rocks. Formation water extractions include the use of oxidizing and reducing agents to extract iodine into carbon tetrachloride. Samples prepared in this way gave good ratio measurements with no contamination. Two methods for iodine extraction from petroleum are employed. The first is a sodium biphenyl extraction which will extract up to 90% of …


Adsorption And Kinetics Of Adsorption By Flyash In Solution, Murthy K. Jogimahanti May 1988

Adsorption And Kinetics Of Adsorption By Flyash In Solution, Murthy K. Jogimahanti

Theses

The phenomena of adsorption is extremely important in water/wastewater treatment process. A process which uses flyash as the sorbent for removing organic compounds from aqueous solutions has been investigated. Also, the rate at which this process occurs, i.e., the kinetics of adsorption, has been studied. Single solute systems were examined and the samples were analyzed using a Flame Ionization Detector Gas Chromatograph. The potentialities of adsorption on flyash as a method of renovation of water have not been realized fully, because little knowledge is available regarding the effective application of the method for this purpose.

Flyash has been known to …


Sorptive And Geotechnical Characteristics Of Kaolinite, Chi-Yuan Shih May 1988

Sorptive And Geotechnical Characteristics Of Kaolinite, Chi-Yuan Shih

Theses

The sorption/desorption behavior of phenol and chlorobenzene as well as their influence on geotechnical characteristics of kaolinite were studied. The results reveal that the sorption process follows closely with the Freundlich adsorption isotherm whereas the sorption/desorption ratio depends upon the characteristics of organic compounds.

A series of geotechnical properties tests was also undertaken after achieving equilibrium at different concentrations of organic compounds. It was found that the parameters such as liquid limit, plastic limit, optimum moisture content, and dry density increase with an increasing-concentration of organic compounds.

The relationship between the geotechnical, properties and sorption behavior of soils provides the …


Bead Design For Biodegradation Of 2-Chlorophenol Using Microorganisms Entrapped In Alginate Gel, Fayaz Lakhwala May 1988

Bead Design For Biodegradation Of 2-Chlorophenol Using Microorganisms Entrapped In Alginate Gel, Fayaz Lakhwala

Theses

The performance of immobilized cell reactors varies with a number of parameters, one of which is proper bead design. A mixed microbial population from a waste water treatment plant was immobilized in calcium alginate gel. The viability of these organisms was studied in a microassay reactor by varying parameters such as concentration of calcium chloride, concentration of sodium alginate, temperature of operation, biomass concentration within the beads and concentration of a model compound (2-chlorophenol). The effect of storage on viability over a period of three months was also investigated. It was found possible to have access to active biomass by …


Biosynthesis Of Amine Oxides Using Calcium-Alginate Immobilized Hog Liver Microsomes : An Evaluation Of Process And Reactor Design, Ioannis I. Valvis May 1988

Biosynthesis Of Amine Oxides Using Calcium-Alginate Immobilized Hog Liver Microsomes : An Evaluation Of Process And Reactor Design, Ioannis I. Valvis

Theses

An evaluation of the biocatalytic ability and the potential utilization of Calcium-alginate immobilized hepatic microsomes (beads) for the biosynthesis of amine oxides has been performed, To accomplish this task, the following three areas Were investigated: immobilization, catalytic biooxidation ability, and reactor configurations.

Immobilization was found to result in higher yields over free microsomes at the expense of higher cofactor requirements. Refrigerated drying of immobilized micro-somes appears to be a better storage technique than wet storage in buffer. Smaller beads resulted in higher rates than larger beads, but size did not affect the overall yield.

Chlorpromazine (CPZ), diphenylamine (DPA) and 4-hydroxy-2,2,6,6-tetramethylpiperidine …


Use Of Recirculation Reactor To Study Biodegradation Of 2-Chlorophenol, Kai-Chung Yang May 1988

Use Of Recirculation Reactor To Study Biodegradation Of 2-Chlorophenol, Kai-Chung Yang

Theses

The performance of immobilized cells in the treatment of hazardous waste was investigated using a recirculation flow reactor run in a batch mode. A mixed microbial population from a municipal wastewater treatment plant was immobilized in calcium alginate gel. The bio-oxidation ability of these microbes towards a model toxin (2-chlorophenol) was studied. The process parameters studied were as follows:

  1. Flow rate of the recycle stream;
  2. Biomass loading;
  3. Spiking concentration of 2-chlorophenol;
  4. Use of buffered vs. non-buffered defined medium.

Dissolved oxygen concentration was monitored using a flow Clark-type dissolved oxygen probe. Oxygen consumption was correlated with the biodegradation of 2-chlorophenol. Physical …


Use Of Recirculation Reactor To Study Biodegradation Of Aroclor 1242, A Polychlorinated Biphenyl, Babu S. Sanji May 1988

Use Of Recirculation Reactor To Study Biodegradation Of Aroclor 1242, A Polychlorinated Biphenyl, Babu S. Sanji

Theses

The performance of immobilized microorganisms in the detoxification of hazardous waste was investigated using a recirculation flow reactor, run in a batch mode. A mixed microbial population from a wastewater treatment plant was immobilized in calcium alginate gel. The bio-oxidation ability of these microbes towards a model toxin Aroclor 1242 (R) (PCB 1242) was studied.

A non-ionic surfactant (Triton X-405 (R)) was used as a medium in the enhancement of the solubility of Aroclor 1242 in aqueous phase.

Dissolved oxygen concentration was monitored using a flow Clark-type dissolved oxygen probe. Oxygen consumption was compared to the biodegradation of Aroclor 1242. …


A New Hazardous Waste Treatment Technology Utilizing Low Power Density Microwave Energy, Gabriele Else Windgasse May 1988

A New Hazardous Waste Treatment Technology Utilizing Low Power Density Microwave Energy, Gabriele Else Windgasse

Theses

Two major applications of a new hazardous waste treatment technology using low power density microwave energy have been characterized: 1) Desorption of organic materials such as: trichloro-ethylene, para-xylene, naphthalene and gasoline hydrocarbons from substrates such as: sand and granulated activated carbon was achieved by microwave induced steam distillation and the application of a new phenomenon: arcing between GAC particles when they are exposed to microwave radiation. All contaminants could be removed to 100% (non-detectable with GC and GC-MS). 2) Decomposition of organic contaminants such as: trichloro-ethylene and trichloro-ethane in arcing/heating GAC beds. A new fluidized bed reactor ("RDW-reactor", after Ray, …


A Dynamic Model Of A Fill-And-Draw Reactor And Its Implications For Hazardous Waste Treatment, Shing-Hwa Chang May 1988

A Dynamic Model Of A Fill-And-Draw Reactor And Its Implications For Hazardous Waste Treatment, Shing-Hwa Chang

Theses

A dynamic model of a fill-and-draw reactor has been developed, which includes a number of operational parameters such as the draw-down volume, the fraction of total cycle time devoted to fill, reaction, and draw, and the concentration of the toxic substance in the feed to the reactor. The model has been solved numerically for two cases, one assuming Monod kinetics, and one considering substrate inhibition (Andrews kinetics).

The conversions achieved with this type of reactor have been compared to that of a conventional activated sludge (CSTR) design. These results indicate that for most practical settings of the operating parameters, the …


Analysis Of Selected Pollutants In Complex Media, Suyi Luo May 1988

Analysis Of Selected Pollutants In Complex Media, Suyi Luo

Theses

Part one: A rapid and reliable procedure is developed for the measurement of the carcinogen benzo(a)pyrene in food. It is a streamlined hybrid of two published methods. These involve ethanalic potassium hydroxide digestion of samples, isooctane extraction, column chromatography on florisil, separation of B(a)P by thin-layer chromatography and measurement of B(a)P by fluorimetry. The recovery of a B(a)P spike of sample is 86.0 + 14.5 % . The procedure which has a limited of detection of 0.05 ng/g (0.05ppb), has been applied to the Human Exposure to B(a)P study.

Part Two: Hexachlorocyclohexane, hexachlorobenzene and some selected PCB congeners were found …


3-D Reconstruction Of Microvasculature From High Voltage Electron Microscopy (Hvem) Data, Pradip Kumar Paul May 1988

3-D Reconstruction Of Microvasculature From High Voltage Electron Microscopy (Hvem) Data, Pradip Kumar Paul

Theses

This is a new method for histoarchitectural and volumetric analyses of cell compartments of microvasculature with the use of a unique combination of computerized 3-D reconstruction and HVEM thick serial cross sections. The technology is potentially a reliable, simple, accurate and fast method. Pioneering work in this area was started by Todd et al. (Circ Res Vol :53 p 319 ;1983) basically using light microscopy, but supported by conventional ultrathin transmission electron microscopy. These techniques are important in that they promise to resolve controversies in terms of evaluating the occurance of hyperplasia and hypertrophy in small resistance vessels in various …


Sorption Characteristics And Their Effects On Geotechnical Properties Of Clay Soils, Arambawattage Mahendra Rodrigo May 1988

Sorption Characteristics And Their Effects On Geotechnical Properties Of Clay Soils, Arambawattage Mahendra Rodrigo

Theses

An experimental investigation on the sorption characteristics of clay soils with liquid organics (phenol, chlorophenol, nitrophenol and chlorobenzene) and their effects upon geotechnical properties was undertaken. The investigation consisted of two different phases, namely, (1) the sorption/ desorption study, including kinetic rate, equilibrium time, isotherm modeling, and (2) geotechnical properties due to clay/ liquid organic interactions. The results of kinetic rate study indicate that the equilibration time for the contaminants way dependent upon the hydrophobic or the hydrophelic nature of the chemical. For equilibrium adsorption models, the linear isotherm was found to be the best fit in predicting sorption capacities …


Effects Of Peripheral And Microwave-Core Heating On Survival In Hemorrhagic Shock In Rats, Ashraf Sabry El-Assuooty May 1988

Effects Of Peripheral And Microwave-Core Heating On Survival In Hemorrhagic Shock In Rats, Ashraf Sabry El-Assuooty

Theses

In a model of rats resuscitated from hemorrhagic shock,where 11 of 12 animals were alive up to 4 hours after shock, there was an average drop of 10°C in core body temperature. Survival and morbidity was much impaired when the shocked animals were externally heated with an infrared lamp to maintain a core body temperature of 35°C. Since the increased intrashock mortality is possibly due to the circulatory changes induced by peripheral heating, an attempt was made to determine the effects of heating the animal at its core. Twelve rats were shocked in the same fashion, however the body core …


The Design, Manufacture And Mechanical Analysis Of An L4-5 Spinal Disc Prosthesis, Bohdan A. Siryi May 1988

The Design, Manufacture And Mechanical Analysis Of An L4-5 Spinal Disc Prosthesis, Bohdan A. Siryi

Theses

The purpose of this research was to develop an intervertebral disc prosthesis which can provide the biomechanical properties of the natural disc. The prosthesis will be used to replace the symptomatic degenerated disc and thereby limit backpain and subsequent spinal disease.

Four cadaveric L4-5 motion segments were mechanically tested under axial compression and combined compression/torsion, generating compressive moduli and torsional stiffness values. Following, prosthetic discs were fabricated and mechanically tested, with the fabrication technique directed towards the optimization of mechanical properties in compression, torsion and bending.

Thirty silicon rubber and forty five polyurethane disc prostheses were fabricated. Silicon rubber, dacron …


Microbial Phenol Degradation Utilizing A Complete-Mix Biological Reactor : The Effects Of Dissolved Oxygen Content, Keith Kollar May 1988

Microbial Phenol Degradation Utilizing A Complete-Mix Biological Reactor : The Effects Of Dissolved Oxygen Content, Keith Kollar

Theses

Experiments were conducted using phenol as a sole carbon source in a series of completely mixed biological reactors with solids recycle (CMBR). The reactor working volume was 4 liters, and solids were recycled from 3 liter clarifiers. Dissolved oxygen concentration (DO) was varied in order to determine the impact of this important variable on system operability.

Phenol was removed at better than 99 percent efficiency during most of the runs. Filamentous growth was not observed during any run. However, bulking did occur at higher DO levels, which was the result of microbial slime production.


Pentachlorophenol And Oxygen Consumption Of Immobilized Mixed Bacterial Culture, Tesfamariam Stephanos Tsadwa May 1988

Pentachlorophenol And Oxygen Consumption Of Immobilized Mixed Bacterial Culture, Tesfamariam Stephanos Tsadwa

Theses

This study was undertaken to investigate the effects of Pentachlorophenol (PCP) concentration on oxygen consumption of immobilized microbial cells. The microbial population, from a municipal wastewater treatment plant, was immobilized in calcium alginate gel. The following studies have also been conducted in this project:

  1. Comparison of the effect of PCP concentration on oxygen uptake between immobilized and free cells.
  2. Comparison of the effects of PCP concentration on oxygen uptake between acclimated and an unacclimated bacterial beads.

Dissolved oxygen concentration was monitored using a flow Clark-type oxygen probe, in a micro-assay bioreactor. It was found that PCP concentrations higher than 2000ppm …


Design Of A Fiber Optic Oxygen Sensor Based On Immobilized Hemoglobin, Mendu Govind Raj May 1988

Design Of A Fiber Optic Oxygen Sensor Based On Immobilized Hemoglobin, Mendu Govind Raj

Theses

The fiber optic Oxygen sensor consists of a thin layer of immobilized deoxyhemoglobin at the common end of a bifurcated fiber. Immobilization is done using the alginate gel procedure. The immobilized reagent is separated from the standard oxygen sample by the gel with or without semi-permeable membrane, and the entire configuration is enclosed in an oxygen free sample cell. Light from a tungsten-halogen lamp, filtered through a 405nm filter is passed through one arm of a bifurcated fiber to the sample cell. The reflected intensity (a highly polished aluminum foil or a plate is placed at the bottom of the …


Metacomprehension: Its Effect On Reading Comprehension Of Third Graders, Lois Funk May 1988

Metacomprehension: Its Effect On Reading Comprehension Of Third Graders, Lois Funk

Theses

Will third grade students, who receive direct instruction in the development of metacomprehension, show greater gains in reading comprehension than students who receive regular instruction based on their teacher's basal manual? The purpose of this study was to compare two groups of third grade students , one control and one experimental, to determine whether direct instruction in the development of metacomprehension would significantly improve third grade reading comprehension.

The hypothesis of this study was that direct instruction in the development of metacomprehension would enable students to receive significantly higher scores in reading comprehension as measured on a standardized comprehension test …


High-Performance Liquid Chromatographic Analysis Of Commonly Used Drugs, Gregg C. Hider May 1988

High-Performance Liquid Chromatographic Analysis Of Commonly Used Drugs, Gregg C. Hider

Theses

This research project had two major goals. Selected members of six groups of clinically useful drugs were obtained to develop and optimize reverse-phase isocratic high-performance liquid chromatographic (HPLO separations using the Hewlett Packard Series 1090 M HPLC. All optimized methods displayed excellent resolution between compounds within a method. Each optimized drug assay developed, displayed good linearity and precision. The second and primary goal of this research project was to provide RIT with a teaching tool. These optimized separations were incorporated into six laboratory experiments, written in a format that RIT's undergraduate students of Medical Technology could easily follow and complete …


Hydrodechlorination Reactions Of Trichloroethylene And 1,1 1, Trichloroethane Over Alumina Supported Palladium Catalysts, And, Trichloroethylene Over Nickel Catalyst, Atul R. Shah Jan 1988

Hydrodechlorination Reactions Of Trichloroethylene And 1,1 1, Trichloroethane Over Alumina Supported Palladium Catalysts, And, Trichloroethylene Over Nickel Catalyst, Atul R. Shah

Theses

The primary objective of this study was to evaluate the viability for conversion of chlorocarbon wastes solvents into useful hydrocarbons and HCl by catalytic reduction. The second objective was to investigate the pathways for these hydrodechlorination reactions over the chosen alumina supported Palladium and nickel catalysts as well as determine selectivities, product distribution, and deactivation mechanism.

Reactions of trichloroethylene with hydrogen over alumina supported palladium catalyst was studied in temperature range 40°C to 57°C at one atmosphere total pressure. The major products observed were ethane and (cis) 1,2 dichloroethylene with trace products chloroethylene, chloroethane and (trans) 1,2 dichloroethylene. At the …


Optimal Design Aspects Of A Unit Treating Hazardous Wastes Via Biodegradation : A Theoretical Approach, Farnaz Saghafi Jan 1988

Optimal Design Aspects Of A Unit Treating Hazardous Wastes Via Biodegradation : A Theoretical Approach, Farnaz Saghafi

Theses

The treatment of wastes via biodegradation is a widely utilized technique in most industries today. The kinetics of biodegradation, in most cases, follow either the Monod (non-inhibitory) or Andrews (also known as Haldane, inhibitory) model as indicated by published experimental data. The present study investigates aspects of the optimal design of a unit treating wastes when the biodegradation kinetics are those mentioned above. The criterion of optimality is the minimum volume achieving a desired conversion under given load conditions.

Two alternatives from the point of view of the number of vessels (one and two), and three alternatives from the operational …